smp: move sub-command "smp_gdb" in file smp.c

[openocd.git] / src / target / cortex_a.c

/***************************************************************************
 *   Copyright (C) 2005 by Dominic Rath                                    *
 *   Dominic.Rath@gmx.de                                                   *
 *                                                                         *
 *   Copyright (C) 2006 by Magnus Lundin                                   *
 *   lundin@mlu.mine.nu                                                    *
 *                                                                         *
 *   Copyright (C) 2008 by Spencer Oliver                                  *
 *   spen@spen-soft.co.uk                                                  *
 *                                                                         *
 *   Copyright (C) 2009 by Dirk Behme                                      *
 *   dirk.behme@gmail.com - copy from cortex_m3                            *
 *                                                                         *
 *   Copyright (C) 2010 Øyvind Harboe                                      *
 *   oyvind.harboe@zylin.com                                               *
 *                                                                         *
 *   Copyright (C) ST-Ericsson SA 2011                                     *
 *   michel.jaouen@stericsson.com : smp minimum support                    *
 *                                                                         *
 *   Copyright (C) Broadcom 2012                                           *
 *   ehunter@broadcom.com : Cortex-R4 support                              *
 *                                                                         *
 *   Copyright (C) 2013 Kamal Dasu                                         *
 *   kdasu.kdev@gmail.com                                                  *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program.  If not, see <http://www.gnu.org/licenses/>. *
 *                                                                         *
 *   Cortex-A8(tm) TRM, ARM DDI 0344H                                      *
 *   Cortex-A9(tm) TRM, ARM DDI 0407F                                      *
 *   Cortex-A4(tm) TRM, ARM DDI 0363E                                      *
 *   Cortex-A15(tm)TRM, ARM DDI 0438C                                      *
 *                                                                         *
 ***************************************************************************/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "breakpoints.h"
#include "cortex_a.h"
#include "register.h"
#include "armv7a_mmu.h"
#include "target_request.h"
#include "target_type.h"
#include "arm_opcodes.h"
#include "arm_semihosting.h"
#include "transport/transport.h"
#include "smp.h"
#include <helper/time_support.h>

static int cortex_a_poll(struct target *target);
static int cortex_a_debug_entry(struct target *target);
static int cortex_a_restore_context(struct target *target, bool bpwp);
static int cortex_a_set_breakpoint(struct target *target,
        struct breakpoint *breakpoint, uint8_t matchmode);
static int cortex_a_set_context_breakpoint(struct target *target,
        struct breakpoint *breakpoint, uint8_t matchmode);
static int cortex_a_set_hybrid_breakpoint(struct target *target,
        struct breakpoint *breakpoint);
static int cortex_a_unset_breakpoint(struct target *target,
        struct breakpoint *breakpoint);
static int cortex_a_mmu(struct target *target, int *enabled);
static int cortex_a_mmu_modify(struct target *target, int enable);
static int cortex_a_virt2phys(struct target *target,
        target_addr_t virt, target_addr_t *phys);
static int cortex_a_read_cpu_memory(struct target *target,
        uint32_t address, uint32_t size, uint32_t count, uint8_t *buffer);


/*  restore cp15_control_reg at resume */
static int cortex_a_restore_cp15_control_reg(struct target *target)
{
        int retval = ERROR_OK;
        struct cortex_a_common *cortex_a = target_to_cortex_a(target);
        struct armv7a_common *armv7a = target_to_armv7a(target);

        if (cortex_a->cp15_control_reg != cortex_a->cp15_control_reg_curr) {
                cortex_a->cp15_control_reg_curr = cortex_a->cp15_control_reg;
                /* LOG_INFO("cp15_control_reg: %8.8" PRIx32, cortex_a->cp15_control_reg); */
                retval = armv7a->arm.mcr(target, 15,
                                0, 0,   /* op1, op2 */
                                1, 0,   /* CRn, CRm */
                                cortex_a->cp15_control_reg);
        }
        return retval;
}

/*
 * Set up ARM core for memory access.
 * If !phys_access, switch to SVC mode and make sure MMU is on
 * If phys_access, switch off mmu
 */
static int cortex_a_prep_memaccess(struct target *target, int phys_access)
{
        struct armv7a_common *armv7a = target_to_armv7a(target);
        struct cortex_a_common *cortex_a = target_to_cortex_a(target);
        int mmu_enabled = 0;

        if (phys_access == 0) {
                arm_dpm_modeswitch(&armv7a->dpm, ARM_MODE_SVC);
                cortex_a_mmu(target, &mmu_enabled);
                if (mmu_enabled)
                        cortex_a_mmu_modify(target, 1);
                if (cortex_a->dacrfixup_mode == CORTEX_A_DACRFIXUP_ON) {
                        /* overwrite DACR to all-manager */
                        armv7a->arm.mcr(target, 15,
                                        0, 0, 3, 0,
                                        0xFFFFFFFF);
                }
        } else {
                cortex_a_mmu(target, &mmu_enabled);
                if (mmu_enabled)
                        cortex_a_mmu_modify(target, 0);
        }
        return ERROR_OK;
}

/*
 * Restore ARM core after memory access.
 * If !phys_access, switch to previous mode
 * If phys_access, restore MMU setting
 */
static int cortex_a_post_memaccess(struct target *target, int phys_access)
{
        struct armv7a_common *armv7a = target_to_armv7a(target);
        struct cortex_a_common *cortex_a = target_to_cortex_a(target);

        if (phys_access == 0) {
                if (cortex_a->dacrfixup_mode == CORTEX_A_DACRFIXUP_ON) {
                        /* restore */
                        armv7a->arm.mcr(target, 15,
                                        0, 0, 3, 0,
                                        cortex_a->cp15_dacr_reg);
                }
                arm_dpm_modeswitch(&armv7a->dpm, ARM_MODE_ANY);
        } else {
                int mmu_enabled = 0;
                cortex_a_mmu(target, &mmu_enabled);
                if (mmu_enabled)
                        cortex_a_mmu_modify(target, 1);
        }
        return ERROR_OK;
}


/*  modify cp15_control_reg in order to enable or disable mmu for :
 *  - virt2phys address conversion
 *  - read or write memory in phys or virt address */
static int cortex_a_mmu_modify(struct target *target, int enable)
{
        struct cortex_a_common *cortex_a = target_to_cortex_a(target);
        struct armv7a_common *armv7a = target_to_armv7a(target);
        int retval = ERROR_OK;
        int need_write = 0;

        if (enable) {
                /*  if mmu enabled at target stop and mmu not enable */
                if (!(cortex_a->cp15_control_reg & 0x1U)) {
                        LOG_ERROR("trying to enable mmu on target stopped with mmu disable");
                        return ERROR_FAIL;
                }
                if ((cortex_a->cp15_control_reg_curr & 0x1U) == 0) {
                        cortex_a->cp15_control_reg_curr |= 0x1U;
                        need_write = 1;
                }
        } else {
                if ((cortex_a->cp15_control_reg_curr & 0x1U) == 0x1U) {
                        cortex_a->cp15_control_reg_curr &= ~0x1U;
                        need_write = 1;
                }
        }

        if (need_write) {
                LOG_DEBUG("%s, writing cp15 ctrl: %" PRIx32,
                        enable ? "enable mmu" : "disable mmu",
                        cortex_a->cp15_control_reg_curr);

                retval = armv7a->arm.mcr(target, 15,
                                0, 0,   /* op1, op2 */
                                1, 0,   /* CRn, CRm */
                                cortex_a->cp15_control_reg_curr);
        }
        return retval;
}

/*
 * Cortex-A Basic debug access, very low level assumes state is saved
 */
static int cortex_a_init_debug_access(struct target *target)
{
        struct armv7a_common *armv7a = target_to_armv7a(target);
        uint32_t dscr;
        int retval;

        /* lock memory-mapped access to debug registers to prevent
         * software interference */
        retval = mem_ap_write_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_LOCKACCESS, 0);
        if (retval != ERROR_OK)
                return retval;

        /* Disable cacheline fills and force cache write-through in debug state */
        retval = mem_ap_write_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DSCCR, 0);
        if (retval != ERROR_OK)
                return retval;

        /* Disable TLB lookup and refill/eviction in debug state */
        retval = mem_ap_write_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DSMCR, 0);
        if (retval != ERROR_OK)
                return retval;

        retval = dap_run(armv7a->debug_ap->dap);
        if (retval != ERROR_OK)
                return retval;

        /* Enabling of instruction execution in debug mode is done in debug_entry code */

        /* Resync breakpoint registers */

        /* Enable halt for breakpoint, watchpoint and vector catch */
        retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DSCR, &dscr);
        if (retval != ERROR_OK)
                return retval;
        retval = mem_ap_write_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DSCR, dscr | DSCR_HALT_DBG_MODE);
        if (retval != ERROR_OK)
                return retval;

        /* Since this is likely called from init or reset, update target state information*/
        return cortex_a_poll(target);
}

static int cortex_a_wait_instrcmpl(struct target *target, uint32_t *dscr, bool force)
{
        /* Waits until InstrCmpl_l becomes 1, indicating instruction is done.
         * Writes final value of DSCR into *dscr. Pass force to force always
         * reading DSCR at least once. */
        struct armv7a_common *armv7a = target_to_armv7a(target);
        int64_t then = timeval_ms();
        while ((*dscr & DSCR_INSTR_COMP) == 0 || force) {
                force = false;
                int retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                                armv7a->debug_base + CPUDBG_DSCR, dscr);
                if (retval != ERROR_OK) {
                        LOG_ERROR("Could not read DSCR register");
                        return retval;
                }
                if (timeval_ms() > then + 1000) {
                        LOG_ERROR("Timeout waiting for InstrCompl=1");
                        return ERROR_FAIL;
                }
        }
        return ERROR_OK;
}

/* To reduce needless round-trips, pass in a pointer to the current
 * DSCR value.  Initialize it to zero if you just need to know the
 * value on return from this function; or DSCR_INSTR_COMP if you
 * happen to know that no instruction is pending.
 */
static int cortex_a_exec_opcode(struct target *target,
        uint32_t opcode, uint32_t *dscr_p)
{
        uint32_t dscr;
        int retval;
        struct armv7a_common *armv7a = target_to_armv7a(target);

        dscr = dscr_p ? *dscr_p : 0;

        LOG_DEBUG("exec opcode 0x%08" PRIx32, opcode);

        /* Wait for InstrCompl bit to be set */
        retval = cortex_a_wait_instrcmpl(target, dscr_p, false);
        if (retval != ERROR_OK)
                return retval;

        retval = mem_ap_write_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_ITR, opcode);
        if (retval != ERROR_OK)
                return retval;

        int64_t then = timeval_ms();
        do {
                retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                                armv7a->debug_base + CPUDBG_DSCR, &dscr);
                if (retval != ERROR_OK) {
                        LOG_ERROR("Could not read DSCR register");
                        return retval;
                }
                if (timeval_ms() > then + 1000) {
                        LOG_ERROR("Timeout waiting for cortex_a_exec_opcode");
                        return ERROR_FAIL;
                }
        } while ((dscr & DSCR_INSTR_COMP) == 0);        /* Wait for InstrCompl bit to be set */

        if (dscr_p)
                *dscr_p = dscr;

        return retval;
}

/* Write to memory mapped registers directly with no cache or mmu handling */
static int cortex_a_dap_write_memap_register_u32(struct target *target,
        uint32_t address,
        uint32_t value)
{
        int retval;
        struct armv7a_common *armv7a = target_to_armv7a(target);

        retval = mem_ap_write_atomic_u32(armv7a->debug_ap, address, value);

        return retval;
}

/*
 * Cortex-A implementation of Debug Programmer's Model
 *
 * NOTE the invariant:  these routines return with DSCR_INSTR_COMP set,
 * so there's no need to poll for it before executing an instruction.
 *
 * NOTE that in several of these cases the "stall" mode might be useful.
 * It'd let us queue a few operations together... prepare/finish might
 * be the places to enable/disable that mode.
 */

static inline struct cortex_a_common *dpm_to_a(struct arm_dpm *dpm)
{
        return container_of(dpm, struct cortex_a_common, armv7a_common.dpm);
}

static int cortex_a_write_dcc(struct cortex_a_common *a, uint32_t data)
{
        LOG_DEBUG("write DCC 0x%08" PRIx32, data);
        return mem_ap_write_u32(a->armv7a_common.debug_ap,
                        a->armv7a_common.debug_base + CPUDBG_DTRRX, data);
}

static int cortex_a_read_dcc(struct cortex_a_common *a, uint32_t *data,
        uint32_t *dscr_p)
{
        uint32_t dscr = DSCR_INSTR_COMP;
        int retval;

        if (dscr_p)
                dscr = *dscr_p;

        /* Wait for DTRRXfull */
        int64_t then = timeval_ms();
        while ((dscr & DSCR_DTR_TX_FULL) == 0) {
                retval = mem_ap_read_atomic_u32(a->armv7a_common.debug_ap,
                                a->armv7a_common.debug_base + CPUDBG_DSCR,
                                &dscr);
                if (retval != ERROR_OK)
                        return retval;
                if (timeval_ms() > then + 1000) {
                        LOG_ERROR("Timeout waiting for read dcc");
                        return ERROR_FAIL;
                }
        }

        retval = mem_ap_read_atomic_u32(a->armv7a_common.debug_ap,
                        a->armv7a_common.debug_base + CPUDBG_DTRTX, data);
        if (retval != ERROR_OK)
                return retval;
        /* LOG_DEBUG("read DCC 0x%08" PRIx32, *data); */

        if (dscr_p)
                *dscr_p = dscr;

        return retval;
}

static int cortex_a_dpm_prepare(struct arm_dpm *dpm)
{
        struct cortex_a_common *a = dpm_to_a(dpm);
        uint32_t dscr;
        int retval;

        /* set up invariant:  INSTR_COMP is set after ever DPM operation */
        int64_t then = timeval_ms();
        for (;; ) {
                retval = mem_ap_read_atomic_u32(a->armv7a_common.debug_ap,
                                a->armv7a_common.debug_base + CPUDBG_DSCR,
                                &dscr);
                if (retval != ERROR_OK)
                        return retval;
                if ((dscr & DSCR_INSTR_COMP) != 0)
                        break;
                if (timeval_ms() > then + 1000) {
                        LOG_ERROR("Timeout waiting for dpm prepare");
                        return ERROR_FAIL;
                }
        }

        /* this "should never happen" ... */
        if (dscr & DSCR_DTR_RX_FULL) {
                LOG_ERROR("DSCR_DTR_RX_FULL, dscr 0x%08" PRIx32, dscr);
                /* Clear DCCRX */
                retval = cortex_a_exec_opcode(
                                a->armv7a_common.arm.target,
                                ARMV4_5_MRC(14, 0, 0, 0, 5, 0),
                                &dscr);
                if (retval != ERROR_OK)
                        return retval;
        }

        return retval;
}

static int cortex_a_dpm_finish(struct arm_dpm *dpm)
{
        /* REVISIT what could be done here? */
        return ERROR_OK;
}

static int cortex_a_instr_write_data_dcc(struct arm_dpm *dpm,
        uint32_t opcode, uint32_t data)
{
        struct cortex_a_common *a = dpm_to_a(dpm);
        int retval;
        uint32_t dscr = DSCR_INSTR_COMP;

        retval = cortex_a_write_dcc(a, data);
        if (retval != ERROR_OK)
                return retval;

        return cortex_a_exec_opcode(
                        a->armv7a_common.arm.target,
                        opcode,
                        &dscr);
}

static int cortex_a_instr_write_data_r0(struct arm_dpm *dpm,
        uint32_t opcode, uint32_t data)
{
        struct cortex_a_common *a = dpm_to_a(dpm);
        uint32_t dscr = DSCR_INSTR_COMP;
        int retval;

        retval = cortex_a_write_dcc(a, data);
        if (retval != ERROR_OK)
                return retval;

        /* DCCRX to R0, "MCR p14, 0, R0, c0, c5, 0", 0xEE000E15 */
        retval = cortex_a_exec_opcode(
                        a->armv7a_common.arm.target,
                        ARMV4_5_MRC(14, 0, 0, 0, 5, 0),
                        &dscr);
        if (retval != ERROR_OK)
                return retval;

        /* then the opcode, taking data from R0 */
        retval = cortex_a_exec_opcode(
                        a->armv7a_common.arm.target,
                        opcode,
                        &dscr);

        return retval;
}

static int cortex_a_instr_cpsr_sync(struct arm_dpm *dpm)
{
        struct target *target = dpm->arm->target;
        uint32_t dscr = DSCR_INSTR_COMP;

        /* "Prefetch flush" after modifying execution status in CPSR */
        return cortex_a_exec_opcode(target,
                        ARMV4_5_MCR(15, 0, 0, 7, 5, 4),
                        &dscr);
}

static int cortex_a_instr_read_data_dcc(struct arm_dpm *dpm,
        uint32_t opcode, uint32_t *data)
{
        struct cortex_a_common *a = dpm_to_a(dpm);
        int retval;
        uint32_t dscr = DSCR_INSTR_COMP;

        /* the opcode, writing data to DCC */
        retval = cortex_a_exec_opcode(
                        a->armv7a_common.arm.target,
                        opcode,
                        &dscr);
        if (retval != ERROR_OK)
                return retval;

        return cortex_a_read_dcc(a, data, &dscr);
}


static int cortex_a_instr_read_data_r0(struct arm_dpm *dpm,
        uint32_t opcode, uint32_t *data)
{
        struct cortex_a_common *a = dpm_to_a(dpm);
        uint32_t dscr = DSCR_INSTR_COMP;
        int retval;

        /* the opcode, writing data to R0 */
        retval = cortex_a_exec_opcode(
                        a->armv7a_common.arm.target,
                        opcode,
                        &dscr);
        if (retval != ERROR_OK)
                return retval;

        /* write R0 to DCC */
        retval = cortex_a_exec_opcode(
                        a->armv7a_common.arm.target,
                        ARMV4_5_MCR(14, 0, 0, 0, 5, 0),
                        &dscr);
        if (retval != ERROR_OK)
                return retval;

        return cortex_a_read_dcc(a, data, &dscr);
}

static int cortex_a_bpwp_enable(struct arm_dpm *dpm, unsigned index_t,
        uint32_t addr, uint32_t control)
{
        struct cortex_a_common *a = dpm_to_a(dpm);
        uint32_t vr = a->armv7a_common.debug_base;
        uint32_t cr = a->armv7a_common.debug_base;
        int retval;

        switch (index_t) {
                case 0 ... 15:  /* breakpoints */
                        vr += CPUDBG_BVR_BASE;
                        cr += CPUDBG_BCR_BASE;
                        break;
                case 16 ... 31: /* watchpoints */
                        vr += CPUDBG_WVR_BASE;
                        cr += CPUDBG_WCR_BASE;
                        index_t -= 16;
                        break;
                default:
                        return ERROR_FAIL;
        }
        vr += 4 * index_t;
        cr += 4 * index_t;

        LOG_DEBUG("A: bpwp enable, vr %08x cr %08x",
                (unsigned) vr, (unsigned) cr);

        retval = cortex_a_dap_write_memap_register_u32(dpm->arm->target,
                        vr, addr);
        if (retval != ERROR_OK)
                return retval;
        retval = cortex_a_dap_write_memap_register_u32(dpm->arm->target,
                        cr, control);
        return retval;
}

static int cortex_a_bpwp_disable(struct arm_dpm *dpm, unsigned index_t)
{
        struct cortex_a_common *a = dpm_to_a(dpm);
        uint32_t cr;

        switch (index_t) {
                case 0 ... 15:
                        cr = a->armv7a_common.debug_base + CPUDBG_BCR_BASE;
                        break;
                case 16 ... 31:
                        cr = a->armv7a_common.debug_base + CPUDBG_WCR_BASE;
                        index_t -= 16;
                        break;
                default:
                        return ERROR_FAIL;
        }
        cr += 4 * index_t;

        LOG_DEBUG("A: bpwp disable, cr %08x", (unsigned) cr);

        /* clear control register */
        return cortex_a_dap_write_memap_register_u32(dpm->arm->target, cr, 0);
}

static int cortex_a_dpm_setup(struct cortex_a_common *a, uint32_t didr)
{
        struct arm_dpm *dpm = &a->armv7a_common.dpm;
        int retval;

        dpm->arm = &a->armv7a_common.arm;
        dpm->didr = didr;

        dpm->prepare = cortex_a_dpm_prepare;
        dpm->finish = cortex_a_dpm_finish;

        dpm->instr_write_data_dcc = cortex_a_instr_write_data_dcc;
        dpm->instr_write_data_r0 = cortex_a_instr_write_data_r0;
        dpm->instr_cpsr_sync = cortex_a_instr_cpsr_sync;

        dpm->instr_read_data_dcc = cortex_a_instr_read_data_dcc;
        dpm->instr_read_data_r0 = cortex_a_instr_read_data_r0;

        dpm->bpwp_enable = cortex_a_bpwp_enable;
        dpm->bpwp_disable = cortex_a_bpwp_disable;

        retval = arm_dpm_setup(dpm);
        if (retval == ERROR_OK)
                retval = arm_dpm_initialize(dpm);

        return retval;
}
static struct target *get_cortex_a(struct target *target, int32_t coreid)
{
        struct target_list *head;
        struct target *curr;

        head = target->head;
        while (head != (struct target_list *)NULL) {
                curr = head->target;
                if ((curr->coreid == coreid) && (curr->state == TARGET_HALTED))
                        return curr;
                head = head->next;
        }
        return target;
}
static int cortex_a_halt(struct target *target);

static int cortex_a_halt_smp(struct target *target)
{
        int retval = 0;
        struct target_list *head;
        struct target *curr;
        head = target->head;
        while (head != (struct target_list *)NULL) {
                curr = head->target;
                if ((curr != target) && (curr->state != TARGET_HALTED)
                        && target_was_examined(curr))
                        retval += cortex_a_halt(curr);
                head = head->next;
        }
        return retval;
}

static int update_halt_gdb(struct target *target)
{
        struct target *gdb_target = NULL;
        struct target_list *head;
        struct target *curr;
        int retval = 0;

        if (target->gdb_service && target->gdb_service->core[0] == -1) {
                target->gdb_service->target = target;
                target->gdb_service->core[0] = target->coreid;
                retval += cortex_a_halt_smp(target);
        }

        if (target->gdb_service)
                gdb_target = target->gdb_service->target;

        foreach_smp_target(head, target->head) {
                curr = head->target;
                /* skip calling context */
                if (curr == target)
                        continue;
                if (!target_was_examined(curr))
                        continue;
                /* skip targets that were already halted */
                if (curr->state == TARGET_HALTED)
                        continue;
                /* Skip gdb_target; it alerts GDB so has to be polled as last one */
                if (curr == gdb_target)
                        continue;

                /* avoid recursion in cortex_a_poll() */
                curr->smp = 0;
                cortex_a_poll(curr);
                curr->smp = 1;
        }

        /* after all targets were updated, poll the gdb serving target */
        if (gdb_target != NULL && gdb_target != target)
                cortex_a_poll(gdb_target);
        return retval;
}

/*
 * Cortex-A Run control
 */

static int cortex_a_poll(struct target *target)
{
        int retval = ERROR_OK;
        uint32_t dscr;
        struct cortex_a_common *cortex_a = target_to_cortex_a(target);
        struct armv7a_common *armv7a = &cortex_a->armv7a_common;
        enum target_state prev_target_state = target->state;
        /*  toggle to another core is done by gdb as follow */
        /*  maint packet J core_id */
        /*  continue */
        /*  the next polling trigger an halt event sent to gdb */
        if ((target->state == TARGET_HALTED) && (target->smp) &&
                (target->gdb_service) &&
                (target->gdb_service->target == NULL)) {
                target->gdb_service->target =
                        get_cortex_a(target, target->gdb_service->core[1]);
                target_call_event_callbacks(target, TARGET_EVENT_HALTED);
                return retval;
        }
        retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DSCR, &dscr);
        if (retval != ERROR_OK)
                return retval;
        cortex_a->cpudbg_dscr = dscr;

        if (DSCR_RUN_MODE(dscr) == (DSCR_CORE_HALTED | DSCR_CORE_RESTARTED)) {
                if (prev_target_state != TARGET_HALTED) {
                        /* We have a halting debug event */
                        LOG_DEBUG("Target halted");
                        target->state = TARGET_HALTED;

                        retval = cortex_a_debug_entry(target);
                        if (retval != ERROR_OK)
                                return retval;

                        if (target->smp) {
                                retval = update_halt_gdb(target);
                                if (retval != ERROR_OK)
                                        return retval;
                        }

                        if (prev_target_state == TARGET_DEBUG_RUNNING) {
                                target_call_event_callbacks(target, TARGET_EVENT_DEBUG_HALTED);
                        } else { /* prev_target_state is RUNNING, UNKNOWN or RESET */
                                if (arm_semihosting(target, &retval) != 0)
                                        return retval;

                                target_call_event_callbacks(target,
                                        TARGET_EVENT_HALTED);
                        }
                }
        } else
                target->state = TARGET_RUNNING;

        return retval;
}

static int cortex_a_halt(struct target *target)
{
        int retval = ERROR_OK;
        uint32_t dscr;
        struct armv7a_common *armv7a = target_to_armv7a(target);

        /*
         * Tell the core to be halted by writing DRCR with 0x1
         * and then wait for the core to be halted.
         */
        retval = mem_ap_write_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DRCR, DRCR_HALT);
        if (retval != ERROR_OK)
                return retval;

        int64_t then = timeval_ms();
        for (;; ) {
                retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                                armv7a->debug_base + CPUDBG_DSCR, &dscr);
                if (retval != ERROR_OK)
                        return retval;
                if ((dscr & DSCR_CORE_HALTED) != 0)
                        break;
                if (timeval_ms() > then + 1000) {
                        LOG_ERROR("Timeout waiting for halt");
                        return ERROR_FAIL;
                }
        }

        target->debug_reason = DBG_REASON_DBGRQ;

        return ERROR_OK;
}

static int cortex_a_internal_restore(struct target *target, int current,
        target_addr_t *address, int handle_breakpoints, int debug_execution)
{
        struct armv7a_common *armv7a = target_to_armv7a(target);
        struct arm *arm = &armv7a->arm;
        int retval;
        uint32_t resume_pc;

        if (!debug_execution)
                target_free_all_working_areas(target);

#if 0
        if (debug_execution) {
                /* Disable interrupts */
                /* We disable interrupts in the PRIMASK register instead of
                 * masking with C_MASKINTS,
                 * This is probably the same issue as Cortex-M3 Errata 377493:
                 * C_MASKINTS in parallel with disabled interrupts can cause
                 * local faults to not be taken. */
                buf_set_u32(armv7m->core_cache->reg_list[ARMV7M_PRIMASK].value, 0, 32, 1);
                armv7m->core_cache->reg_list[ARMV7M_PRIMASK].dirty = true;
                armv7m->core_cache->reg_list[ARMV7M_PRIMASK].valid = true;

                /* Make sure we are in Thumb mode */
                buf_set_u32(armv7m->core_cache->reg_list[ARMV7M_xPSR].value, 0, 32,
                        buf_get_u32(armv7m->core_cache->reg_list[ARMV7M_xPSR].value, 0,
                        32) | (1 << 24));
                armv7m->core_cache->reg_list[ARMV7M_xPSR].dirty = true;
                armv7m->core_cache->reg_list[ARMV7M_xPSR].valid = true;
        }
#endif

        /* current = 1: continue on current pc, otherwise continue at <address> */
        resume_pc = buf_get_u32(arm->pc->value, 0, 32);
        if (!current)
                resume_pc = *address;
        else
                *address = resume_pc;

        /* Make sure that the Armv7 gdb thumb fixups does not
         * kill the return address
         */
        switch (arm->core_state) {
                case ARM_STATE_ARM:
                        resume_pc &= 0xFFFFFFFC;
                        break;
                case ARM_STATE_THUMB:
                case ARM_STATE_THUMB_EE:
                        /* When the return address is loaded into PC
                         * bit 0 must be 1 to stay in Thumb state
                         */
                        resume_pc |= 0x1;
                        break;
                case ARM_STATE_JAZELLE:
                        LOG_ERROR("How do I resume into Jazelle state??");
                        return ERROR_FAIL;
                case ARM_STATE_AARCH64:
                        LOG_ERROR("Shoudn't be in AARCH64 state");
                        return ERROR_FAIL;
        }
        LOG_DEBUG("resume pc = 0x%08" PRIx32, resume_pc);
        buf_set_u32(arm->pc->value, 0, 32, resume_pc);
        arm->pc->dirty = true;
        arm->pc->valid = true;

        /* restore dpm_mode at system halt */
        arm_dpm_modeswitch(&armv7a->dpm, ARM_MODE_ANY);
        /* called it now before restoring context because it uses cpu
         * register r0 for restoring cp15 control register */
        retval = cortex_a_restore_cp15_control_reg(target);
        if (retval != ERROR_OK)
                return retval;
        retval = cortex_a_restore_context(target, handle_breakpoints);
        if (retval != ERROR_OK)
                return retval;
        target->debug_reason = DBG_REASON_NOTHALTED;
        target->state = TARGET_RUNNING;

        /* registers are now invalid */
        register_cache_invalidate(arm->core_cache);

#if 0
        /* the front-end may request us not to handle breakpoints */
        if (handle_breakpoints) {
                /* Single step past breakpoint at current address */
                breakpoint = breakpoint_find(target, resume_pc);
                if (breakpoint) {
                        LOG_DEBUG("unset breakpoint at 0x%8.8x", breakpoint->address);
                        cortex_m3_unset_breakpoint(target, breakpoint);
                        cortex_m3_single_step_core(target);
                        cortex_m3_set_breakpoint(target, breakpoint);
                }
        }

#endif
        return retval;
}

static int cortex_a_internal_restart(struct target *target)
{
        struct armv7a_common *armv7a = target_to_armv7a(target);
        struct arm *arm = &armv7a->arm;
        int retval;
        uint32_t dscr;
        /*
         * * Restart core and wait for it to be started.  Clear ITRen and sticky
         * * exception flags: see ARMv7 ARM, C5.9.
         *
         * REVISIT: for single stepping, we probably want to
         * disable IRQs by default, with optional override...
         */

        retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DSCR, &dscr);
        if (retval != ERROR_OK)
                return retval;

        if ((dscr & DSCR_INSTR_COMP) == 0)
                LOG_ERROR("DSCR InstrCompl must be set before leaving debug!");

        retval = mem_ap_write_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DSCR, dscr & ~DSCR_ITR_EN);
        if (retval != ERROR_OK)
                return retval;

        retval = mem_ap_write_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DRCR, DRCR_RESTART |
                        DRCR_CLEAR_EXCEPTIONS);
        if (retval != ERROR_OK)
                return retval;

        int64_t then = timeval_ms();
        for (;; ) {
                retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                                armv7a->debug_base + CPUDBG_DSCR, &dscr);
                if (retval != ERROR_OK)
                        return retval;
                if ((dscr & DSCR_CORE_RESTARTED) != 0)
                        break;
                if (timeval_ms() > then + 1000) {
                        LOG_ERROR("Timeout waiting for resume");
                        return ERROR_FAIL;
                }
        }

        target->debug_reason = DBG_REASON_NOTHALTED;
        target->state = TARGET_RUNNING;

        /* registers are now invalid */
        register_cache_invalidate(arm->core_cache);

        return ERROR_OK;
}

static int cortex_a_restore_smp(struct target *target, int handle_breakpoints)
{
        int retval = 0;
        struct target_list *head;
        struct target *curr;
        target_addr_t address;
        head = target->head;
        while (head != (struct target_list *)NULL) {
                curr = head->target;
                if ((curr != target) && (curr->state != TARGET_RUNNING)
                        && target_was_examined(curr)) {
                        /*  resume current address , not in step mode */
                        retval += cortex_a_internal_restore(curr, 1, &address,
                                        handle_breakpoints, 0);
                        retval += cortex_a_internal_restart(curr);
                }
                head = head->next;

        }
        return retval;
}

static int cortex_a_resume(struct target *target, int current,
        target_addr_t address, int handle_breakpoints, int debug_execution)
{
        int retval = 0;
        /* dummy resume for smp toggle in order to reduce gdb impact  */
        if ((target->smp) && (target->gdb_service->core[1] != -1)) {
                /*   simulate a start and halt of target */
                target->gdb_service->target = NULL;
                target->gdb_service->core[0] = target->gdb_service->core[1];
                /*  fake resume at next poll we play the  target core[1], see poll*/
                target_call_event_callbacks(target, TARGET_EVENT_RESUMED);
                return 0;
        }
        cortex_a_internal_restore(target, current, &address, handle_breakpoints, debug_execution);
        if (target->smp) {
                target->gdb_service->core[0] = -1;
                retval = cortex_a_restore_smp(target, handle_breakpoints);
                if (retval != ERROR_OK)
                        return retval;
        }
        cortex_a_internal_restart(target);

        if (!debug_execution) {
                target->state = TARGET_RUNNING;
                target_call_event_callbacks(target, TARGET_EVENT_RESUMED);
                LOG_DEBUG("target resumed at " TARGET_ADDR_FMT, address);
        } else {
                target->state = TARGET_DEBUG_RUNNING;
                target_call_event_callbacks(target, TARGET_EVENT_DEBUG_RESUMED);
                LOG_DEBUG("target debug resumed at " TARGET_ADDR_FMT, address);
        }

        return ERROR_OK;
}

static int cortex_a_debug_entry(struct target *target)
{
        uint32_t dscr;
        int retval = ERROR_OK;
        struct cortex_a_common *cortex_a = target_to_cortex_a(target);
        struct armv7a_common *armv7a = target_to_armv7a(target);
        struct arm *arm = &armv7a->arm;

        LOG_DEBUG("dscr = 0x%08" PRIx32, cortex_a->cpudbg_dscr);

        /* REVISIT surely we should not re-read DSCR !! */
        retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DSCR, &dscr);
        if (retval != ERROR_OK)
                return retval;

        /* REVISIT see A TRM 12.11.4 steps 2..3 -- make sure that any
         * imprecise data aborts get discarded by issuing a Data
         * Synchronization Barrier:  ARMV4_5_MCR(15, 0, 0, 7, 10, 4).
         */

        /* Enable the ITR execution once we are in debug mode */
        dscr |= DSCR_ITR_EN;
        retval = mem_ap_write_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DSCR, dscr);
        if (retval != ERROR_OK)
                return retval;

        /* Examine debug reason */
        arm_dpm_report_dscr(&armv7a->dpm, cortex_a->cpudbg_dscr);

        /* save address of instruction that triggered the watchpoint? */
        if (target->debug_reason == DBG_REASON_WATCHPOINT) {
                uint32_t wfar;

                retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                                armv7a->debug_base + CPUDBG_WFAR,
                                &wfar);
                if (retval != ERROR_OK)
                        return retval;
                arm_dpm_report_wfar(&armv7a->dpm, wfar);
        }

        /* First load register accessible through core debug port */
        retval = arm_dpm_read_current_registers(&armv7a->dpm);
        if (retval != ERROR_OK)
                return retval;

        if (arm->spsr) {
                /* read SPSR */
                retval = arm_dpm_read_reg(&armv7a->dpm, arm->spsr, 17);
                if (retval != ERROR_OK)
                        return retval;
        }

#if 0
/* TODO, Move this */
        uint32_t cp15_control_register, cp15_cacr, cp15_nacr;
        cortex_a_read_cp(target, &cp15_control_register, 15, 0, 1, 0, 0);
        LOG_DEBUG("cp15_control_register = 0x%08x", cp15_control_register);

        cortex_a_read_cp(target, &cp15_cacr, 15, 0, 1, 0, 2);
        LOG_DEBUG("cp15 Coprocessor Access Control Register = 0x%08x", cp15_cacr);

        cortex_a_read_cp(target, &cp15_nacr, 15, 0, 1, 1, 2);
        LOG_DEBUG("cp15 Nonsecure Access Control Register = 0x%08x", cp15_nacr);
#endif

        /* Are we in an exception handler */
/*      armv4_5->exception_number = 0; */
        if (armv7a->post_debug_entry) {
                retval = armv7a->post_debug_entry(target);
                if (retval != ERROR_OK)
                        return retval;
        }

        return retval;
}

static int cortex_a_post_debug_entry(struct target *target)
{
        struct cortex_a_common *cortex_a = target_to_cortex_a(target);
        struct armv7a_common *armv7a = &cortex_a->armv7a_common;
        int retval;

        /* MRC p15,0,<Rt>,c1,c0,0 ; Read CP15 System Control Register */
        retval = armv7a->arm.mrc(target, 15,
                        0, 0,   /* op1, op2 */
                        1, 0,   /* CRn, CRm */
                        &cortex_a->cp15_control_reg);
        if (retval != ERROR_OK)
                return retval;
        LOG_DEBUG("cp15_control_reg: %8.8" PRIx32, cortex_a->cp15_control_reg);
        cortex_a->cp15_control_reg_curr = cortex_a->cp15_control_reg;

        if (!armv7a->is_armv7r)
                armv7a_read_ttbcr(target);

        if (armv7a->armv7a_mmu.armv7a_cache.info == -1)
                armv7a_identify_cache(target);

        if (armv7a->is_armv7r) {
                armv7a->armv7a_mmu.mmu_enabled = 0;
        } else {
                armv7a->armv7a_mmu.mmu_enabled =
                        (cortex_a->cp15_control_reg & 0x1U) ? 1 : 0;
        }
        armv7a->armv7a_mmu.armv7a_cache.d_u_cache_enabled =
                (cortex_a->cp15_control_reg & 0x4U) ? 1 : 0;
        armv7a->armv7a_mmu.armv7a_cache.i_cache_enabled =
                (cortex_a->cp15_control_reg & 0x1000U) ? 1 : 0;
        cortex_a->curr_mode = armv7a->arm.core_mode;

        /* switch to SVC mode to read DACR */
        arm_dpm_modeswitch(&armv7a->dpm, ARM_MODE_SVC);
        armv7a->arm.mrc(target, 15,
                        0, 0, 3, 0,
                        &cortex_a->cp15_dacr_reg);

        LOG_DEBUG("cp15_dacr_reg: %8.8" PRIx32,
                        cortex_a->cp15_dacr_reg);

        arm_dpm_modeswitch(&armv7a->dpm, ARM_MODE_ANY);
        return ERROR_OK;
}

int cortex_a_set_dscr_bits(struct target *target, unsigned long bit_mask, unsigned long value)
{
        struct armv7a_common *armv7a = target_to_armv7a(target);
        uint32_t dscr;

        /* Read DSCR */
        int retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DSCR, &dscr);
        if (ERROR_OK != retval)
                return retval;

        /* clear bitfield */
        dscr &= ~bit_mask;
        /* put new value */
        dscr |= value & bit_mask;

        /* write new DSCR */
        retval = mem_ap_write_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DSCR, dscr);
        return retval;
}

static int cortex_a_step(struct target *target, int current, target_addr_t address,
        int handle_breakpoints)
{
        struct cortex_a_common *cortex_a = target_to_cortex_a(target);
        struct armv7a_common *armv7a = target_to_armv7a(target);
        struct arm *arm = &armv7a->arm;
        struct breakpoint *breakpoint = NULL;
        struct breakpoint stepbreakpoint;
        struct reg *r;
        int retval;

        if (target->state != TARGET_HALTED) {
                LOG_WARNING("target not halted");
                return ERROR_TARGET_NOT_HALTED;
        }

        /* current = 1: continue on current pc, otherwise continue at <address> */
        r = arm->pc;
        if (!current)
                buf_set_u32(r->value, 0, 32, address);
        else
                address = buf_get_u32(r->value, 0, 32);

        /* The front-end may request us not to handle breakpoints.
         * But since Cortex-A uses breakpoint for single step,
         * we MUST handle breakpoints.
         */
        handle_breakpoints = 1;
        if (handle_breakpoints) {
                breakpoint = breakpoint_find(target, address);
                if (breakpoint)
                        cortex_a_unset_breakpoint(target, breakpoint);
        }

        /* Setup single step breakpoint */
        stepbreakpoint.address = address;
        stepbreakpoint.asid = 0;
        stepbreakpoint.length = (arm->core_state == ARM_STATE_THUMB)
                ? 2 : 4;
        stepbreakpoint.type = BKPT_HARD;
        stepbreakpoint.set = 0;

        /* Disable interrupts during single step if requested */
        if (cortex_a->isrmasking_mode == CORTEX_A_ISRMASK_ON) {
                retval = cortex_a_set_dscr_bits(target, DSCR_INT_DIS, DSCR_INT_DIS);
                if (ERROR_OK != retval)
                        return retval;
        }

        /* Break on IVA mismatch */
        cortex_a_set_breakpoint(target, &stepbreakpoint, 0x04);

        target->debug_reason = DBG_REASON_SINGLESTEP;

        retval = cortex_a_resume(target, 1, address, 0, 0);
        if (retval != ERROR_OK)
                return retval;

        int64_t then = timeval_ms();
        while (target->state != TARGET_HALTED) {
                retval = cortex_a_poll(target);
                if (retval != ERROR_OK)
                        return retval;
                if (timeval_ms() > then + 1000) {
                        LOG_ERROR("timeout waiting for target halt");
                        return ERROR_FAIL;
                }
        }

        cortex_a_unset_breakpoint(target, &stepbreakpoint);

        /* Re-enable interrupts if they were disabled */
        if (cortex_a->isrmasking_mode == CORTEX_A_ISRMASK_ON) {
                retval = cortex_a_set_dscr_bits(target, DSCR_INT_DIS, 0);
                if (ERROR_OK != retval)
                        return retval;
        }


        target->debug_reason = DBG_REASON_BREAKPOINT;

        if (breakpoint)
                cortex_a_set_breakpoint(target, breakpoint, 0);

        if (target->state != TARGET_HALTED)
                LOG_DEBUG("target stepped");

        return ERROR_OK;
}

static int cortex_a_restore_context(struct target *target, bool bpwp)
{
        struct armv7a_common *armv7a = target_to_armv7a(target);

        LOG_DEBUG(" ");

        if (armv7a->pre_restore_context)
                armv7a->pre_restore_context(target);

        return arm_dpm_write_dirty_registers(&armv7a->dpm, bpwp);
}

/*
 * Cortex-A Breakpoint and watchpoint functions
 */

/* Setup hardware Breakpoint Register Pair */
static int cortex_a_set_breakpoint(struct target *target,
        struct breakpoint *breakpoint, uint8_t matchmode)
{
        int retval;
        int brp_i = 0;
        uint32_t control;
        uint8_t byte_addr_select = 0x0F;
        struct cortex_a_common *cortex_a = target_to_cortex_a(target);
        struct armv7a_common *armv7a = &cortex_a->armv7a_common;
        struct cortex_a_brp *brp_list = cortex_a->brp_list;

        if (breakpoint->set) {
                LOG_WARNING("breakpoint already set");
                return ERROR_OK;
        }

        if (breakpoint->type == BKPT_HARD) {
                while (brp_list[brp_i].used && (brp_i < cortex_a->brp_num))
                        brp_i++;
                if (brp_i >= cortex_a->brp_num) {
                        LOG_ERROR("ERROR Can not find free Breakpoint Register Pair");
                        return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
                }
                breakpoint->set = brp_i + 1;
                if (breakpoint->length == 2)
                        byte_addr_select = (3 << (breakpoint->address & 0x02));
                control = ((matchmode & 0x7) << 20)
                        | (byte_addr_select << 5)
                        | (3 << 1) | 1;
                brp_list[brp_i].used = 1;
                brp_list[brp_i].value = (breakpoint->address & 0xFFFFFFFC);
                brp_list[brp_i].control = control;
                retval = cortex_a_dap_write_memap_register_u32(target, armv7a->debug_base
                                + CPUDBG_BVR_BASE + 4 * brp_list[brp_i].BRPn,
                                brp_list[brp_i].value);
                if (retval != ERROR_OK)
                        return retval;
                retval = cortex_a_dap_write_memap_register_u32(target, armv7a->debug_base
                                + CPUDBG_BCR_BASE + 4 * brp_list[brp_i].BRPn,
                                brp_list[brp_i].control);
                if (retval != ERROR_OK)
                        return retval;
                LOG_DEBUG("brp %i control 0x%0" PRIx32 " value 0x%0" PRIx32, brp_i,
                        brp_list[brp_i].control,
                        brp_list[brp_i].value);
        } else if (breakpoint->type == BKPT_SOFT) {
                uint8_t code[4];
                /* length == 2: Thumb breakpoint */
                if (breakpoint->length == 2)
                        buf_set_u32(code, 0, 32, ARMV5_T_BKPT(0x11));
                else
                /* length == 3: Thumb-2 breakpoint, actual encoding is
                 * a regular Thumb BKPT instruction but we replace a
                 * 32bit Thumb-2 instruction, so fix-up the breakpoint
                 * length
                 */
                if (breakpoint->length == 3) {
                        buf_set_u32(code, 0, 32, ARMV5_T_BKPT(0x11));
                        breakpoint->length = 4;
                } else
                        /* length == 4, normal ARM breakpoint */
                        buf_set_u32(code, 0, 32, ARMV5_BKPT(0x11));

                retval = target_read_memory(target,
                                breakpoint->address & 0xFFFFFFFE,
                                breakpoint->length, 1,
                                breakpoint->orig_instr);
                if (retval != ERROR_OK)
                        return retval;

                /* make sure data cache is cleaned & invalidated down to PoC */
                if (!armv7a->armv7a_mmu.armv7a_cache.auto_cache_enabled) {
                        armv7a_cache_flush_virt(target, breakpoint->address,
                                                breakpoint->length);
                }

                retval = target_write_memory(target,
                                breakpoint->address & 0xFFFFFFFE,
                                breakpoint->length, 1, code);
                if (retval != ERROR_OK)
                        return retval;

                /* update i-cache at breakpoint location */
                armv7a_l1_d_cache_inval_virt(target, breakpoint->address,
                                        breakpoint->length);
                armv7a_l1_i_cache_inval_virt(target, breakpoint->address,
                                                 breakpoint->length);

                breakpoint->set = 0x11; /* Any nice value but 0 */
        }

        return ERROR_OK;
}

static int cortex_a_set_context_breakpoint(struct target *target,
        struct breakpoint *breakpoint, uint8_t matchmode)
{
        int retval = ERROR_FAIL;
        int brp_i = 0;
        uint32_t control;
        uint8_t byte_addr_select = 0x0F;
        struct cortex_a_common *cortex_a = target_to_cortex_a(target);
        struct armv7a_common *armv7a = &cortex_a->armv7a_common;
        struct cortex_a_brp *brp_list = cortex_a->brp_list;

        if (breakpoint->set) {
                LOG_WARNING("breakpoint already set");
                return retval;
        }
        /*check available context BRPs*/
        while ((brp_list[brp_i].used ||
                (brp_list[brp_i].type != BRP_CONTEXT)) && (brp_i < cortex_a->brp_num))
                brp_i++;

        if (brp_i >= cortex_a->brp_num) {
                LOG_ERROR("ERROR Can not find free Breakpoint Register Pair");
                return ERROR_FAIL;
        }

        breakpoint->set = brp_i + 1;
        control = ((matchmode & 0x7) << 20)
                | (byte_addr_select << 5)
                | (3 << 1) | 1;
        brp_list[brp_i].used = 1;
        brp_list[brp_i].value = (breakpoint->asid);
        brp_list[brp_i].control = control;
        retval = cortex_a_dap_write_memap_register_u32(target, armv7a->debug_base
                        + CPUDBG_BVR_BASE + 4 * brp_list[brp_i].BRPn,
                        brp_list[brp_i].value);
        if (retval != ERROR_OK)
                return retval;
        retval = cortex_a_dap_write_memap_register_u32(target, armv7a->debug_base
                        + CPUDBG_BCR_BASE + 4 * brp_list[brp_i].BRPn,
                        brp_list[brp_i].control);
        if (retval != ERROR_OK)
                return retval;
        LOG_DEBUG("brp %i control 0x%0" PRIx32 " value 0x%0" PRIx32, brp_i,
                brp_list[brp_i].control,
                brp_list[brp_i].value);
        return ERROR_OK;

}

static int cortex_a_set_hybrid_breakpoint(struct target *target, struct breakpoint *breakpoint)
{
        int retval = ERROR_FAIL;
        int brp_1 = 0;  /* holds the contextID pair */
        int brp_2 = 0;  /* holds the IVA pair */
        uint32_t control_CTX, control_IVA;
        uint8_t CTX_byte_addr_select = 0x0F;
        uint8_t IVA_byte_addr_select = 0x0F;
        uint8_t CTX_machmode = 0x03;
        uint8_t IVA_machmode = 0x01;
        struct cortex_a_common *cortex_a = target_to_cortex_a(target);
        struct armv7a_common *armv7a = &cortex_a->armv7a_common;
        struct cortex_a_brp *brp_list = cortex_a->brp_list;

        if (breakpoint->set) {
                LOG_WARNING("breakpoint already set");
                return retval;
        }
        /*check available context BRPs*/
        while ((brp_list[brp_1].used ||
                (brp_list[brp_1].type != BRP_CONTEXT)) && (brp_1 < cortex_a->brp_num))
                brp_1++;

        printf("brp(CTX) found num: %d\n", brp_1);
        if (brp_1 >= cortex_a->brp_num) {
                LOG_ERROR("ERROR Can not find free Breakpoint Register Pair");
                return ERROR_FAIL;
        }

        while ((brp_list[brp_2].used ||
                (brp_list[brp_2].type != BRP_NORMAL)) && (brp_2 < cortex_a->brp_num))
                brp_2++;

        printf("brp(IVA) found num: %d\n", brp_2);
        if (brp_2 >= cortex_a->brp_num) {
                LOG_ERROR("ERROR Can not find free Breakpoint Register Pair");
                return ERROR_FAIL;
        }

        breakpoint->set = brp_1 + 1;
        breakpoint->linked_BRP = brp_2;
        control_CTX = ((CTX_machmode & 0x7) << 20)
                | (brp_2 << 16)
                | (0 << 14)
                | (CTX_byte_addr_select << 5)
                | (3 << 1) | 1;
        brp_list[brp_1].used = 1;
        brp_list[brp_1].value = (breakpoint->asid);
        brp_list[brp_1].control = control_CTX;
        retval = cortex_a_dap_write_memap_register_u32(target, armv7a->debug_base
                        + CPUDBG_BVR_BASE + 4 * brp_list[brp_1].BRPn,
                        brp_list[brp_1].value);
        if (retval != ERROR_OK)
                return retval;
        retval = cortex_a_dap_write_memap_register_u32(target, armv7a->debug_base
                        + CPUDBG_BCR_BASE + 4 * brp_list[brp_1].BRPn,
                        brp_list[brp_1].control);
        if (retval != ERROR_OK)
                return retval;

        control_IVA = ((IVA_machmode & 0x7) << 20)
                | (brp_1 << 16)
                | (IVA_byte_addr_select << 5)
                | (3 << 1) | 1;
        brp_list[brp_2].used = 1;
        brp_list[brp_2].value = (breakpoint->address & 0xFFFFFFFC);
        brp_list[brp_2].control = control_IVA;
        retval = cortex_a_dap_write_memap_register_u32(target, armv7a->debug_base
                        + CPUDBG_BVR_BASE + 4 * brp_list[brp_2].BRPn,
                        brp_list[brp_2].value);
        if (retval != ERROR_OK)
                return retval;
        retval = cortex_a_dap_write_memap_register_u32(target, armv7a->debug_base
                        + CPUDBG_BCR_BASE + 4 * brp_list[brp_2].BRPn,
                        brp_list[brp_2].control);
        if (retval != ERROR_OK)
                return retval;

        return ERROR_OK;
}

static int cortex_a_unset_breakpoint(struct target *target, struct breakpoint *breakpoint)
{
        int retval;
        struct cortex_a_common *cortex_a = target_to_cortex_a(target);
        struct armv7a_common *armv7a = &cortex_a->armv7a_common;
        struct cortex_a_brp *brp_list = cortex_a->brp_list;

        if (!breakpoint->set) {
                LOG_WARNING("breakpoint not set");
                return ERROR_OK;
        }

        if (breakpoint->type == BKPT_HARD) {
                if ((breakpoint->address != 0) && (breakpoint->asid != 0)) {
                        int brp_i = breakpoint->set - 1;
                        int brp_j = breakpoint->linked_BRP;
                        if ((brp_i < 0) || (brp_i >= cortex_a->brp_num)) {
                                LOG_DEBUG("Invalid BRP number in breakpoint");
                                return ERROR_OK;
                        }
                        LOG_DEBUG("rbp %i control 0x%0" PRIx32 " value 0x%0" PRIx32, brp_i,
                                brp_list[brp_i].control, brp_list[brp_i].value);
                        brp_list[brp_i].used = 0;
                        brp_list[brp_i].value = 0;
                        brp_list[brp_i].control = 0;
                        retval = cortex_a_dap_write_memap_register_u32(target, armv7a->debug_base
                                        + CPUDBG_BCR_BASE + 4 * brp_list[brp_i].BRPn,
                                        brp_list[brp_i].control);
                        if (retval != ERROR_OK)
                                return retval;
                        retval = cortex_a_dap_write_memap_register_u32(target, armv7a->debug_base
                                        + CPUDBG_BVR_BASE + 4 * brp_list[brp_i].BRPn,
                                        brp_list[brp_i].value);
                        if (retval != ERROR_OK)
                                return retval;
                        if ((brp_j < 0) || (brp_j >= cortex_a->brp_num)) {
                                LOG_DEBUG("Invalid BRP number in breakpoint");
                                return ERROR_OK;
                        }
                        LOG_DEBUG("rbp %i control 0x%0" PRIx32 " value 0x%0" PRIx32, brp_j,
                                brp_list[brp_j].control, brp_list[brp_j].value);
                        brp_list[brp_j].used = 0;
                        brp_list[brp_j].value = 0;
                        brp_list[brp_j].control = 0;
                        retval = cortex_a_dap_write_memap_register_u32(target, armv7a->debug_base
                                        + CPUDBG_BCR_BASE + 4 * brp_list[brp_j].BRPn,
                                        brp_list[brp_j].control);
                        if (retval != ERROR_OK)
                                return retval;
                        retval = cortex_a_dap_write_memap_register_u32(target, armv7a->debug_base
                                        + CPUDBG_BVR_BASE + 4 * brp_list[brp_j].BRPn,
                                        brp_list[brp_j].value);
                        if (retval != ERROR_OK)
                                return retval;
                        breakpoint->linked_BRP = 0;
                        breakpoint->set = 0;
                        return ERROR_OK;

                } else {
                        int brp_i = breakpoint->set - 1;
                        if ((brp_i < 0) || (brp_i >= cortex_a->brp_num)) {
                                LOG_DEBUG("Invalid BRP number in breakpoint");
                                return ERROR_OK;
                        }
                        LOG_DEBUG("rbp %i control 0x%0" PRIx32 " value 0x%0" PRIx32, brp_i,
                                brp_list[brp_i].control, brp_list[brp_i].value);
                        brp_list[brp_i].used = 0;
                        brp_list[brp_i].value = 0;
                        brp_list[brp_i].control = 0;
                        retval = cortex_a_dap_write_memap_register_u32(target, armv7a->debug_base
                                        + CPUDBG_BCR_BASE + 4 * brp_list[brp_i].BRPn,
                                        brp_list[brp_i].control);
                        if (retval != ERROR_OK)
                                return retval;
                        retval = cortex_a_dap_write_memap_register_u32(target, armv7a->debug_base
                                        + CPUDBG_BVR_BASE + 4 * brp_list[brp_i].BRPn,
                                        brp_list[brp_i].value);
                        if (retval != ERROR_OK)
                                return retval;
                        breakpoint->set = 0;
                        return ERROR_OK;
                }
        } else {

                /* make sure data cache is cleaned & invalidated down to PoC */
                if (!armv7a->armv7a_mmu.armv7a_cache.auto_cache_enabled) {
                        armv7a_cache_flush_virt(target, breakpoint->address,
                                                breakpoint->length);
                }

                /* restore original instruction (kept in target endianness) */
                if (breakpoint->length == 4) {
                        retval = target_write_memory(target,
                                        breakpoint->address & 0xFFFFFFFE,
                                        4, 1, breakpoint->orig_instr);
                        if (retval != ERROR_OK)
                                return retval;
                } else {
                        retval = target_write_memory(target,
                                        breakpoint->address & 0xFFFFFFFE,
                                        2, 1, breakpoint->orig_instr);
                        if (retval != ERROR_OK)
                                return retval;
                }

                /* update i-cache at breakpoint location */
                armv7a_l1_d_cache_inval_virt(target, breakpoint->address,
                                                 breakpoint->length);
                armv7a_l1_i_cache_inval_virt(target, breakpoint->address,
                                                 breakpoint->length);
        }
        breakpoint->set = 0;

        return ERROR_OK;
}

static int cortex_a_add_breakpoint(struct target *target,
        struct breakpoint *breakpoint)
{
        struct cortex_a_common *cortex_a = target_to_cortex_a(target);

        if ((breakpoint->type == BKPT_HARD) && (cortex_a->brp_num_available < 1)) {
                LOG_INFO("no hardware breakpoint available");
                return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
        }

        if (breakpoint->type == BKPT_HARD)
                cortex_a->brp_num_available--;

        return cortex_a_set_breakpoint(target, breakpoint, 0x00);       /* Exact match */
}

static int cortex_a_add_context_breakpoint(struct target *target,
        struct breakpoint *breakpoint)
{
        struct cortex_a_common *cortex_a = target_to_cortex_a(target);

        if ((breakpoint->type == BKPT_HARD) && (cortex_a->brp_num_available < 1)) {
                LOG_INFO("no hardware breakpoint available");
                return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
        }

        if (breakpoint->type == BKPT_HARD)
                cortex_a->brp_num_available--;

        return cortex_a_set_context_breakpoint(target, breakpoint, 0x02);       /* asid match */
}

static int cortex_a_add_hybrid_breakpoint(struct target *target,
        struct breakpoint *breakpoint)
{
        struct cortex_a_common *cortex_a = target_to_cortex_a(target);

        if ((breakpoint->type == BKPT_HARD) && (cortex_a->brp_num_available < 1)) {
                LOG_INFO("no hardware breakpoint available");
                return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
        }

        if (breakpoint->type == BKPT_HARD)
                cortex_a->brp_num_available--;

        return cortex_a_set_hybrid_breakpoint(target, breakpoint);      /* ??? */
}


static int cortex_a_remove_breakpoint(struct target *target, struct breakpoint *breakpoint)
{
        struct cortex_a_common *cortex_a = target_to_cortex_a(target);

#if 0
/* It is perfectly possible to remove breakpoints while the target is running */
        if (target->state != TARGET_HALTED) {
                LOG_WARNING("target not halted");
                return ERROR_TARGET_NOT_HALTED;
        }
#endif

        if (breakpoint->set) {
                cortex_a_unset_breakpoint(target, breakpoint);
                if (breakpoint->type == BKPT_HARD)
                        cortex_a->brp_num_available++;
        }


        return ERROR_OK;
}

/*
 * Cortex-A Reset functions
 */

static int cortex_a_assert_reset(struct target *target)
{
        struct armv7a_common *armv7a = target_to_armv7a(target);

        LOG_DEBUG(" ");

        /* FIXME when halt is requested, make it work somehow... */

        /* This function can be called in "target not examined" state */

        /* Issue some kind of warm reset. */
        if (target_has_event_action(target, TARGET_EVENT_RESET_ASSERT))
                target_handle_event(target, TARGET_EVENT_RESET_ASSERT);
        else if (jtag_get_reset_config() & RESET_HAS_SRST) {
                /* REVISIT handle "pulls" cases, if there's
                 * hardware that needs them to work.
                 */

                /*
                 * FIXME: fix reset when transport is SWD. This is a temporary
                 * work-around for release v0.10 that is not intended to stay!
                 */
                if (transport_is_swd() ||
                                (target->reset_halt && (jtag_get_reset_config() & RESET_SRST_NO_GATING)))
                        jtag_add_reset(0, 1);

        } else {
                LOG_ERROR("%s: how to reset?", target_name(target));
                return ERROR_FAIL;
        }

        /* registers are now invalid */
        if (target_was_examined(target))
                register_cache_invalidate(armv7a->arm.core_cache);

        target->state = TARGET_RESET;

        return ERROR_OK;
}

static int cortex_a_deassert_reset(struct target *target)
{
        int retval;

        LOG_DEBUG(" ");

        /* be certain SRST is off */
        jtag_add_reset(0, 0);

        if (target_was_examined(target)) {
                retval = cortex_a_poll(target);
                if (retval != ERROR_OK)
                        return retval;
        }

        if (target->reset_halt) {
                if (target->state != TARGET_HALTED) {
                        LOG_WARNING("%s: ran after reset and before halt ...",
                                target_name(target));
                        if (target_was_examined(target)) {
                                retval = target_halt(target);
                                if (retval != ERROR_OK)
                                        return retval;
                        } else
                                target->state = TARGET_UNKNOWN;
                }
        }

        return ERROR_OK;
}

static int cortex_a_set_dcc_mode(struct target *target, uint32_t mode, uint32_t *dscr)
{
        /* Changes the mode of the DCC between non-blocking, stall, and fast mode.
         * New desired mode must be in mode. Current value of DSCR must be in
         * *dscr, which is updated with new value.
         *
         * This function elides actually sending the mode-change over the debug
         * interface if the mode is already set as desired.
         */
        uint32_t new_dscr = (*dscr & ~DSCR_EXT_DCC_MASK) | mode;
        if (new_dscr != *dscr) {
                struct armv7a_common *armv7a = target_to_armv7a(target);
                int retval = mem_ap_write_atomic_u32(armv7a->debug_ap,
                                armv7a->debug_base + CPUDBG_DSCR, new_dscr);
                if (retval == ERROR_OK)
                        *dscr = new_dscr;
                return retval;
        } else {
                return ERROR_OK;
        }
}

static int cortex_a_wait_dscr_bits(struct target *target, uint32_t mask,
        uint32_t value, uint32_t *dscr)
{
        /* Waits until the specified bit(s) of DSCR take on a specified value. */
        struct armv7a_common *armv7a = target_to_armv7a(target);
        int64_t then = timeval_ms();
        int retval;

        while ((*dscr & mask) != value) {
                retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                                armv7a->debug_base + CPUDBG_DSCR, dscr);
                if (retval != ERROR_OK)
                        return retval;
                if (timeval_ms() > then + 1000) {
                        LOG_ERROR("timeout waiting for DSCR bit change");
                        return ERROR_FAIL;
                }
        }
        return ERROR_OK;
}

static int cortex_a_read_copro(struct target *target, uint32_t opcode,
        uint32_t *data, uint32_t *dscr)
{
        int retval;
        struct armv7a_common *armv7a = target_to_armv7a(target);

        /* Move from coprocessor to R0. */
        retval = cortex_a_exec_opcode(target, opcode, dscr);
        if (retval != ERROR_OK)
                return retval;

        /* Move from R0 to DTRTX. */
        retval = cortex_a_exec_opcode(target, ARMV4_5_MCR(14, 0, 0, 0, 5, 0), dscr);
        if (retval != ERROR_OK)
                return retval;

        /* Wait until DTRTX is full (according to ARMv7-A/-R architecture
         * manual section C8.4.3, checking InstrCmpl_l is not sufficient; one
         * must also check TXfull_l). Most of the time this will be free
         * because TXfull_l will be set immediately and cached in dscr. */
        retval = cortex_a_wait_dscr_bits(target, DSCR_DTRTX_FULL_LATCHED,
                        DSCR_DTRTX_FULL_LATCHED, dscr);
        if (retval != ERROR_OK)
                return retval;

        /* Read the value transferred to DTRTX. */
        retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DTRTX, data);
        if (retval != ERROR_OK)
                return retval;

        return ERROR_OK;
}

static int cortex_a_read_dfar_dfsr(struct target *target, uint32_t *dfar,
        uint32_t *dfsr, uint32_t *dscr)
{
        int retval;

        if (dfar) {
                retval = cortex_a_read_copro(target, ARMV4_5_MRC(15, 0, 0, 6, 0, 0), dfar, dscr);
                if (retval != ERROR_OK)
                        return retval;
        }

        if (dfsr) {
                retval = cortex_a_read_copro(target, ARMV4_5_MRC(15, 0, 0, 5, 0, 0), dfsr, dscr);
                if (retval != ERROR_OK)
                        return retval;
        }

        return ERROR_OK;
}

static int cortex_a_write_copro(struct target *target, uint32_t opcode,
        uint32_t data, uint32_t *dscr)
{
        int retval;
        struct armv7a_common *armv7a = target_to_armv7a(target);

        /* Write the value into DTRRX. */
        retval = mem_ap_write_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DTRRX, data);
        if (retval != ERROR_OK)
                return retval;

        /* Move from DTRRX to R0. */
        retval = cortex_a_exec_opcode(target, ARMV4_5_MRC(14, 0, 0, 0, 5, 0), dscr);
        if (retval != ERROR_OK)
                return retval;

        /* Move from R0 to coprocessor. */
        retval = cortex_a_exec_opcode(target, opcode, dscr);
        if (retval != ERROR_OK)
                return retval;

        /* Wait until DTRRX is empty (according to ARMv7-A/-R architecture manual
         * section C8.4.3, checking InstrCmpl_l is not sufficient; one must also
         * check RXfull_l). Most of the time this will be free because RXfull_l
         * will be cleared immediately and cached in dscr. */
        retval = cortex_a_wait_dscr_bits(target, DSCR_DTRRX_FULL_LATCHED, 0, dscr);
        if (retval != ERROR_OK)
                return retval;

        return ERROR_OK;
}

static int cortex_a_write_dfar_dfsr(struct target *target, uint32_t dfar,
        uint32_t dfsr, uint32_t *dscr)
{
        int retval;

        retval = cortex_a_write_copro(target, ARMV4_5_MCR(15, 0, 0, 6, 0, 0), dfar, dscr);
        if (retval != ERROR_OK)
                return retval;

        retval = cortex_a_write_copro(target, ARMV4_5_MCR(15, 0, 0, 5, 0, 0), dfsr, dscr);
        if (retval != ERROR_OK)
                return retval;

        return ERROR_OK;
}

static int cortex_a_dfsr_to_error_code(uint32_t dfsr)
{
        uint32_t status, upper4;

        if (dfsr & (1 << 9)) {
                /* LPAE format. */
                status = dfsr & 0x3f;
                upper4 = status >> 2;
                if (upper4 == 1 || upper4 == 2 || upper4 == 3 || upper4 == 15)
                        return ERROR_TARGET_TRANSLATION_FAULT;
                else if (status == 33)
                        return ERROR_TARGET_UNALIGNED_ACCESS;
                else
                        return ERROR_TARGET_DATA_ABORT;
        } else {
                /* Normal format. */
                status = ((dfsr >> 6) & 0x10) | (dfsr & 0xf);
                if (status == 1)
                        return ERROR_TARGET_UNALIGNED_ACCESS;
                else if (status == 5 || status == 7 || status == 3 || status == 6 ||
                                status == 9 || status == 11 || status == 13 || status == 15)
                        return ERROR_TARGET_TRANSLATION_FAULT;
                else
                        return ERROR_TARGET_DATA_ABORT;
        }
}

static int cortex_a_write_cpu_memory_slow(struct target *target,
        uint32_t size, uint32_t count, const uint8_t *buffer, uint32_t *dscr)
{
        /* Writes count objects of size size from *buffer. Old value of DSCR must
         * be in *dscr; updated to new value. This is slow because it works for
         * non-word-sized objects and (maybe) unaligned accesses. If size == 4 and
         * the address is aligned, cortex_a_write_cpu_memory_fast should be
         * preferred.
         * Preconditions:
         * - Address is in R0.
         * - R0 is marked dirty.
         */
        struct armv7a_common *armv7a = target_to_armv7a(target);
        struct arm *arm = &armv7a->arm;
        int retval;

        /* Mark register R1 as dirty, to use for transferring data. */
        arm_reg_current(arm, 1)->dirty = true;

        /* Switch to non-blocking mode if not already in that mode. */
        retval = cortex_a_set_dcc_mode(target, DSCR_EXT_DCC_NON_BLOCKING, dscr);
        if (retval != ERROR_OK)
                return retval;

        /* Go through the objects. */
        while (count) {
                /* Write the value to store into DTRRX. */
                uint32_t data, opcode;
                if (size == 1)
                        data = *buffer;
                else if (size == 2)
                        data = target_buffer_get_u16(target, buffer);
                else
                        data = target_buffer_get_u32(target, buffer);
                retval = mem_ap_write_atomic_u32(armv7a->debug_ap,
                                armv7a->debug_base + CPUDBG_DTRRX, data);
                if (retval != ERROR_OK)
                        return retval;

                /* Transfer the value from DTRRX to R1. */
                retval = cortex_a_exec_opcode(target, ARMV4_5_MRC(14, 0, 1, 0, 5, 0), dscr);
                if (retval != ERROR_OK)
                        return retval;

                /* Write the value transferred to R1 into memory. */
                if (size == 1)
                        opcode = ARMV4_5_STRB_IP(1, 0);
                else if (size == 2)
                        opcode = ARMV4_5_STRH_IP(1, 0);
                else
                        opcode = ARMV4_5_STRW_IP(1, 0);
                retval = cortex_a_exec_opcode(target, opcode, dscr);
                if (retval != ERROR_OK)
                        return retval;

                /* Check for faults and return early. */
                if (*dscr & (DSCR_STICKY_ABORT_PRECISE | DSCR_STICKY_ABORT_IMPRECISE))
                        return ERROR_OK; /* A data fault is not considered a system failure. */

                /* Wait until DTRRX is empty (according to ARMv7-A/-R architecture
                 * manual section C8.4.3, checking InstrCmpl_l is not sufficient; one
                 * must also check RXfull_l). Most of the time this will be free
                 * because RXfull_l will be cleared immediately and cached in dscr. */
                retval = cortex_a_wait_dscr_bits(target, DSCR_DTRRX_FULL_LATCHED, 0, dscr);
                if (retval != ERROR_OK)
                        return retval;

                /* Advance. */
                buffer += size;
                --count;
        }

        return ERROR_OK;
}

static int cortex_a_write_cpu_memory_fast(struct target *target,
        uint32_t count, const uint8_t *buffer, uint32_t *dscr)
{
        /* Writes count objects of size 4 from *buffer. Old value of DSCR must be
         * in *dscr; updated to new value. This is fast but only works for
         * word-sized objects at aligned addresses.
         * Preconditions:
         * - Address is in R0 and must be a multiple of 4.
         * - R0 is marked dirty.
         */
        struct armv7a_common *armv7a = target_to_armv7a(target);
        int retval;

        /* Switch to fast mode if not already in that mode. */
        retval = cortex_a_set_dcc_mode(target, DSCR_EXT_DCC_FAST_MODE, dscr);
        if (retval != ERROR_OK)
                return retval;

        /* Latch STC instruction. */
        retval = mem_ap_write_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_ITR, ARMV4_5_STC(0, 1, 0, 1, 14, 5, 0, 4));
        if (retval != ERROR_OK)
                return retval;

        /* Transfer all the data and issue all the instructions. */
        return mem_ap_write_buf_noincr(armv7a->debug_ap, buffer,
                        4, count, armv7a->debug_base + CPUDBG_DTRRX);
}

static int cortex_a_write_cpu_memory(struct target *target,
        uint32_t address, uint32_t size,
        uint32_t count, const uint8_t *buffer)
{
        /* Write memory through the CPU. */
        int retval, final_retval;
        struct armv7a_common *armv7a = target_to_armv7a(target);
        struct arm *arm = &armv7a->arm;
        uint32_t dscr, orig_dfar, orig_dfsr, fault_dscr, fault_dfar, fault_dfsr;

        LOG_DEBUG("Writing CPU memory address 0x%" PRIx32 " size %"  PRIu32 " count %"  PRIu32,
                          address, size, count);
        if (target->state != TARGET_HALTED) {
                LOG_WARNING("target not halted");
                return ERROR_TARGET_NOT_HALTED;
        }

        if (!count)
                return ERROR_OK;

        /* Clear any abort. */
        retval = mem_ap_write_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DRCR, DRCR_CLEAR_EXCEPTIONS);
        if (retval != ERROR_OK)
                return retval;

        /* Read DSCR. */
        retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DSCR, &dscr);
        if (retval != ERROR_OK)
                return retval;

        /* Switch to non-blocking mode if not already in that mode. */
        retval = cortex_a_set_dcc_mode(target, DSCR_EXT_DCC_NON_BLOCKING, &dscr);
        if (retval != ERROR_OK)
                goto out;

        /* Mark R0 as dirty. */
        arm_reg_current(arm, 0)->dirty = true;

        /* Read DFAR and DFSR, as they will be modified in the event of a fault. */
        retval = cortex_a_read_dfar_dfsr(target, &orig_dfar, &orig_dfsr, &dscr);
        if (retval != ERROR_OK)
                goto out;

        /* Get the memory address into R0. */
        retval = mem_ap_write_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DTRRX, address);
        if (retval != ERROR_OK)
                goto out;
        retval = cortex_a_exec_opcode(target, ARMV4_5_MRC(14, 0, 0, 0, 5, 0), &dscr);
        if (retval != ERROR_OK)
                goto out;

        if (size == 4 && (address % 4) == 0) {
                /* We are doing a word-aligned transfer, so use fast mode. */
                retval = cortex_a_write_cpu_memory_fast(target, count, buffer, &dscr);
        } else {
                /* Use slow path. */
                retval = cortex_a_write_cpu_memory_slow(target, size, count, buffer, &dscr);
        }

out:
        final_retval = retval;

        /* Switch to non-blocking mode if not already in that mode. */
        retval = cortex_a_set_dcc_mode(target, DSCR_EXT_DCC_NON_BLOCKING, &dscr);
        if (final_retval == ERROR_OK)
                final_retval = retval;

        /* Wait for last issued instruction to complete. */
        retval = cortex_a_wait_instrcmpl(target, &dscr, true);
        if (final_retval == ERROR_OK)
                final_retval = retval;

        /* Wait until DTRRX is empty (according to ARMv7-A/-R architecture manual
         * section C8.4.3, checking InstrCmpl_l is not sufficient; one must also
         * check RXfull_l). Most of the time this will be free because RXfull_l
         * will be cleared immediately and cached in dscr. However, don't do this
         * if there is fault, because then the instruction might not have completed
         * successfully. */
        if (!(dscr & DSCR_STICKY_ABORT_PRECISE)) {
                retval = cortex_a_wait_dscr_bits(target, DSCR_DTRRX_FULL_LATCHED, 0, &dscr);
                if (retval != ERROR_OK)
                        return retval;
        }

        /* If there were any sticky abort flags, clear them. */
        if (dscr & (DSCR_STICKY_ABORT_PRECISE | DSCR_STICKY_ABORT_IMPRECISE)) {
                fault_dscr = dscr;
                mem_ap_write_atomic_u32(armv7a->debug_ap,
                                armv7a->debug_base + CPUDBG_DRCR, DRCR_CLEAR_EXCEPTIONS);
                dscr &= ~(DSCR_STICKY_ABORT_PRECISE | DSCR_STICKY_ABORT_IMPRECISE);
        } else {
                fault_dscr = 0;
        }

        /* Handle synchronous data faults. */
        if (fault_dscr & DSCR_STICKY_ABORT_PRECISE) {
                if (final_retval == ERROR_OK) {
                        /* Final return value will reflect cause of fault. */
                        retval = cortex_a_read_dfar_dfsr(target, &fault_dfar, &fault_dfsr, &dscr);
                        if (retval == ERROR_OK) {
                                LOG_ERROR("data abort at 0x%08" PRIx32 ", dfsr = 0x%08" PRIx32, fault_dfar, fault_dfsr);
                                final_retval = cortex_a_dfsr_to_error_code(fault_dfsr);
                        } else
                                final_retval = retval;
                }
                /* Fault destroyed DFAR/DFSR; restore them. */
                retval = cortex_a_write_dfar_dfsr(target, orig_dfar, orig_dfsr, &dscr);
                if (retval != ERROR_OK)
                        LOG_ERROR("error restoring dfar/dfsr - dscr = 0x%08" PRIx32, dscr);
        }

        /* Handle asynchronous data faults. */
        if (fault_dscr & DSCR_STICKY_ABORT_IMPRECISE) {
                if (final_retval == ERROR_OK)
                        /* No other error has been recorded so far, so keep this one. */
                        final_retval = ERROR_TARGET_DATA_ABORT;
        }

        /* If the DCC is nonempty, clear it. */
        if (dscr & DSCR_DTRTX_FULL_LATCHED) {
                uint32_t dummy;
                retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                                armv7a->debug_base + CPUDBG_DTRTX, &dummy);
                if (final_retval == ERROR_OK)
                        final_retval = retval;
        }
        if (dscr & DSCR_DTRRX_FULL_LATCHED) {
                retval = cortex_a_exec_opcode(target, ARMV4_5_MRC(14, 0, 1, 0, 5, 0), &dscr);
                if (final_retval == ERROR_OK)
                        final_retval = retval;
        }

        /* Done. */
        return final_retval;
}

static int cortex_a_read_cpu_memory_slow(struct target *target,
        uint32_t size, uint32_t count, uint8_t *buffer, uint32_t *dscr)
{
        /* Reads count objects of size size into *buffer. Old value of DSCR must be
         * in *dscr; updated to new value. This is slow because it works for
         * non-word-sized objects and (maybe) unaligned accesses. If size == 4 and
         * the address is aligned, cortex_a_read_cpu_memory_fast should be
         * preferred.
         * Preconditions:
         * - Address is in R0.
         * - R0 is marked dirty.
         */
        struct armv7a_common *armv7a = target_to_armv7a(target);
        struct arm *arm = &armv7a->arm;
        int retval;

        /* Mark register R1 as dirty, to use for transferring data. */
        arm_reg_current(arm, 1)->dirty = true;

        /* Switch to non-blocking mode if not already in that mode. */
        retval = cortex_a_set_dcc_mode(target, DSCR_EXT_DCC_NON_BLOCKING, dscr);
        if (retval != ERROR_OK)
                return retval;

        /* Go through the objects. */
        while (count) {
                /* Issue a load of the appropriate size to R1. */
                uint32_t opcode, data;
                if (size == 1)
                        opcode = ARMV4_5_LDRB_IP(1, 0);
                else if (size == 2)
                        opcode = ARMV4_5_LDRH_IP(1, 0);
                else
                        opcode = ARMV4_5_LDRW_IP(1, 0);
                retval = cortex_a_exec_opcode(target, opcode, dscr);
                if (retval != ERROR_OK)
                        return retval;

                /* Issue a write of R1 to DTRTX. */
                retval = cortex_a_exec_opcode(target, ARMV4_5_MCR(14, 0, 1, 0, 5, 0), dscr);
                if (retval != ERROR_OK)
                        return retval;

                /* Check for faults and return early. */
                if (*dscr & (DSCR_STICKY_ABORT_PRECISE | DSCR_STICKY_ABORT_IMPRECISE))
                        return ERROR_OK; /* A data fault is not considered a system failure. */

                /* Wait until DTRTX is full (according to ARMv7-A/-R architecture
                 * manual section C8.4.3, checking InstrCmpl_l is not sufficient; one
                 * must also check TXfull_l). Most of the time this will be free
                 * because TXfull_l will be set immediately and cached in dscr. */
                retval = cortex_a_wait_dscr_bits(target, DSCR_DTRTX_FULL_LATCHED,
                                DSCR_DTRTX_FULL_LATCHED, dscr);
                if (retval != ERROR_OK)
                        return retval;

                /* Read the value transferred to DTRTX into the buffer. */
                retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                                armv7a->debug_base + CPUDBG_DTRTX, &data);
                if (retval != ERROR_OK)
                        return retval;
                if (size == 1)
                        *buffer = (uint8_t) data;
                else if (size == 2)
                        target_buffer_set_u16(target, buffer, (uint16_t) data);
                else
                        target_buffer_set_u32(target, buffer, data);

                /* Advance. */
                buffer += size;
                --count;
        }

        return ERROR_OK;
}

static int cortex_a_read_cpu_memory_fast(struct target *target,
        uint32_t count, uint8_t *buffer, uint32_t *dscr)
{
        /* Reads count objects of size 4 into *buffer. Old value of DSCR must be in
         * *dscr; updated to new value. This is fast but only works for word-sized
         * objects at aligned addresses.
         * Preconditions:
         * - Address is in R0 and must be a multiple of 4.
         * - R0 is marked dirty.
         */
        struct armv7a_common *armv7a = target_to_armv7a(target);
        uint32_t u32;
        int retval;

        /* Switch to non-blocking mode if not already in that mode. */
        retval = cortex_a_set_dcc_mode(target, DSCR_EXT_DCC_NON_BLOCKING, dscr);
        if (retval != ERROR_OK)
                return retval;

        /* Issue the LDC instruction via a write to ITR. */
        retval = cortex_a_exec_opcode(target, ARMV4_5_LDC(0, 1, 0, 1, 14, 5, 0, 4), dscr);
        if (retval != ERROR_OK)
                return retval;

        count--;

        if (count > 0) {
                /* Switch to fast mode if not already in that mode. */
                retval = cortex_a_set_dcc_mode(target, DSCR_EXT_DCC_FAST_MODE, dscr);
                if (retval != ERROR_OK)
                        return retval;

                /* Latch LDC instruction. */
                retval = mem_ap_write_atomic_u32(armv7a->debug_ap,
                                armv7a->debug_base + CPUDBG_ITR, ARMV4_5_LDC(0, 1, 0, 1, 14, 5, 0, 4));
                if (retval != ERROR_OK)
                        return retval;

                /* Read the value transferred to DTRTX into the buffer. Due to fast
                 * mode rules, this blocks until the instruction finishes executing and
                 * then reissues the read instruction to read the next word from
                 * memory. The last read of DTRTX in this call reads the second-to-last
                 * word from memory and issues the read instruction for the last word.
                 */
                retval = mem_ap_read_buf_noincr(armv7a->debug_ap, buffer,
                                4, count, armv7a->debug_base + CPUDBG_DTRTX);
                if (retval != ERROR_OK)
                        return retval;

                /* Advance. */
                buffer += count * 4;
        }

        /* Wait for last issued instruction to complete. */
        retval = cortex_a_wait_instrcmpl(target, dscr, false);
        if (retval != ERROR_OK)
                return retval;

        /* Switch to non-blocking mode if not already in that mode. */
        retval = cortex_a_set_dcc_mode(target, DSCR_EXT_DCC_NON_BLOCKING, dscr);
        if (retval != ERROR_OK)
                return retval;

        /* Check for faults and return early. */
        if (*dscr & (DSCR_STICKY_ABORT_PRECISE | DSCR_STICKY_ABORT_IMPRECISE))
                return ERROR_OK; /* A data fault is not considered a system failure. */

        /* Wait until DTRTX is full (according to ARMv7-A/-R architecture manual
         * section C8.4.3, checking InstrCmpl_l is not sufficient; one must also
         * check TXfull_l). Most of the time this will be free because TXfull_l
         * will be set immediately and cached in dscr. */
        retval = cortex_a_wait_dscr_bits(target, DSCR_DTRTX_FULL_LATCHED,
                        DSCR_DTRTX_FULL_LATCHED, dscr);
        if (retval != ERROR_OK)
                return retval;

        /* Read the value transferred to DTRTX into the buffer. This is the last
         * word. */
        retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DTRTX, &u32);
        if (retval != ERROR_OK)
                return retval;
        target_buffer_set_u32(target, buffer, u32);

        return ERROR_OK;
}

static int cortex_a_read_cpu_memory(struct target *target,
        uint32_t address, uint32_t size,
        uint32_t count, uint8_t *buffer)
{
        /* Read memory through the CPU. */
        int retval, final_retval;
        struct armv7a_common *armv7a = target_to_armv7a(target);
        struct arm *arm = &armv7a->arm;
        uint32_t dscr, orig_dfar, orig_dfsr, fault_dscr, fault_dfar, fault_dfsr;

        LOG_DEBUG("Reading CPU memory address 0x%" PRIx32 " size %"  PRIu32 " count %"  PRIu32,
                          address, size, count);
        if (target->state != TARGET_HALTED) {
                LOG_WARNING("target not halted");
                return ERROR_TARGET_NOT_HALTED;
        }

        if (!count)
                return ERROR_OK;

        /* Clear any abort. */
        retval = mem_ap_write_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DRCR, DRCR_CLEAR_EXCEPTIONS);
        if (retval != ERROR_OK)
                return retval;

        /* Read DSCR */
        retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DSCR, &dscr);
        if (retval != ERROR_OK)
                return retval;

        /* Switch to non-blocking mode if not already in that mode. */
        retval = cortex_a_set_dcc_mode(target, DSCR_EXT_DCC_NON_BLOCKING, &dscr);
        if (retval != ERROR_OK)
                goto out;

        /* Mark R0 as dirty. */
        arm_reg_current(arm, 0)->dirty = true;

        /* Read DFAR and DFSR, as they will be modified in the event of a fault. */
        retval = cortex_a_read_dfar_dfsr(target, &orig_dfar, &orig_dfsr, &dscr);
        if (retval != ERROR_OK)
                goto out;

        /* Get the memory address into R0. */
        retval = mem_ap_write_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DTRRX, address);
        if (retval != ERROR_OK)
                goto out;
        retval = cortex_a_exec_opcode(target, ARMV4_5_MRC(14, 0, 0, 0, 5, 0), &dscr);
        if (retval != ERROR_OK)
                goto out;

        if (size == 4 && (address % 4) == 0) {
                /* We are doing a word-aligned transfer, so use fast mode. */
                retval = cortex_a_read_cpu_memory_fast(target, count, buffer, &dscr);
        } else {
                /* Use slow path. */
                retval = cortex_a_read_cpu_memory_slow(target, size, count, buffer, &dscr);
        }

out:
        final_retval = retval;

        /* Switch to non-blocking mode if not already in that mode. */
        retval = cortex_a_set_dcc_mode(target, DSCR_EXT_DCC_NON_BLOCKING, &dscr);
        if (final_retval == ERROR_OK)
                final_retval = retval;

        /* Wait for last issued instruction to complete. */
        retval = cortex_a_wait_instrcmpl(target, &dscr, true);
        if (final_retval == ERROR_OK)
                final_retval = retval;

        /* If there were any sticky abort flags, clear them. */
        if (dscr & (DSCR_STICKY_ABORT_PRECISE | DSCR_STICKY_ABORT_IMPRECISE)) {
                fault_dscr = dscr;
                mem_ap_write_atomic_u32(armv7a->debug_ap,
                                armv7a->debug_base + CPUDBG_DRCR, DRCR_CLEAR_EXCEPTIONS);
                dscr &= ~(DSCR_STICKY_ABORT_PRECISE | DSCR_STICKY_ABORT_IMPRECISE);
        } else {
                fault_dscr = 0;
        }

        /* Handle synchronous data faults. */
        if (fault_dscr & DSCR_STICKY_ABORT_PRECISE) {
                if (final_retval == ERROR_OK) {
                        /* Final return value will reflect cause of fault. */
                        retval = cortex_a_read_dfar_dfsr(target, &fault_dfar, &fault_dfsr, &dscr);
                        if (retval == ERROR_OK) {
                                LOG_ERROR("data abort at 0x%08" PRIx32 ", dfsr = 0x%08" PRIx32, fault_dfar, fault_dfsr);
                                final_retval = cortex_a_dfsr_to_error_code(fault_dfsr);
                        } else
                                final_retval = retval;
                }
                /* Fault destroyed DFAR/DFSR; restore them. */
                retval = cortex_a_write_dfar_dfsr(target, orig_dfar, orig_dfsr, &dscr);
                if (retval != ERROR_OK)
                        LOG_ERROR("error restoring dfar/dfsr - dscr = 0x%08" PRIx32, dscr);
        }

        /* Handle asynchronous data faults. */
        if (fault_dscr & DSCR_STICKY_ABORT_IMPRECISE) {
                if (final_retval == ERROR_OK)
                        /* No other error has been recorded so far, so keep this one. */
                        final_retval = ERROR_TARGET_DATA_ABORT;
        }

        /* If the DCC is nonempty, clear it. */
        if (dscr & DSCR_DTRTX_FULL_LATCHED) {
                uint32_t dummy;
                retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                                armv7a->debug_base + CPUDBG_DTRTX, &dummy);
                if (final_retval == ERROR_OK)
                        final_retval = retval;
        }
        if (dscr & DSCR_DTRRX_FULL_LATCHED) {
                retval = cortex_a_exec_opcode(target, ARMV4_5_MRC(14, 0, 1, 0, 5, 0), &dscr);
                if (final_retval == ERROR_OK)
                        final_retval = retval;
        }

        /* Done. */
        return final_retval;
}


/*
 * Cortex-A Memory access
 *
 * This is same Cortex-M3 but we must also use the correct
 * ap number for every access.
 */

static int cortex_a_read_phys_memory(struct target *target,
        target_addr_t address, uint32_t size,
        uint32_t count, uint8_t *buffer)
{
        int retval;

        if (!count || !buffer)
                return ERROR_COMMAND_SYNTAX_ERROR;

        LOG_DEBUG("Reading memory at real address " TARGET_ADDR_FMT "; size %" PRId32 "; count %" PRId32,
                address, size, count);

        /* read memory through the CPU */
        cortex_a_prep_memaccess(target, 1);
        retval = cortex_a_read_cpu_memory(target, address, size, count, buffer);
        cortex_a_post_memaccess(target, 1);

        return retval;
}

static int cortex_a_read_memory(struct target *target, target_addr_t address,
        uint32_t size, uint32_t count, uint8_t *buffer)
{
        int retval;

        /* cortex_a handles unaligned memory access */
        LOG_DEBUG("Reading memory at address " TARGET_ADDR_FMT "; size %" PRId32 "; count %" PRId32,
                address, size, count);

        cortex_a_prep_memaccess(target, 0);
        retval = cortex_a_read_cpu_memory(target, address, size, count, buffer);
        cortex_a_post_memaccess(target, 0);

        return retval;
}

static int cortex_a_write_phys_memory(struct target *target,
        target_addr_t address, uint32_t size,
        uint32_t count, const uint8_t *buffer)
{
        int retval;

        if (!count || !buffer)
                return ERROR_COMMAND_SYNTAX_ERROR;

        LOG_DEBUG("Writing memory to real address " TARGET_ADDR_FMT "; size %" PRId32 "; count %" PRId32,
                address, size, count);

        /* write memory through the CPU */
        cortex_a_prep_memaccess(target, 1);
        retval = cortex_a_write_cpu_memory(target, address, size, count, buffer);
        cortex_a_post_memaccess(target, 1);

        return retval;
}

static int cortex_a_write_memory(struct target *target, target_addr_t address,
        uint32_t size, uint32_t count, const uint8_t *buffer)
{
        int retval;

        /* cortex_a handles unaligned memory access */
        LOG_DEBUG("Writing memory at address " TARGET_ADDR_FMT "; size %" PRId32 "; count %" PRId32,
                address, size, count);

        /* memory writes bypass the caches, must flush before writing */
        armv7a_cache_auto_flush_on_write(target, address, size * count);

        cortex_a_prep_memaccess(target, 0);
        retval = cortex_a_write_cpu_memory(target, address, size, count, buffer);
        cortex_a_post_memaccess(target, 0);
        return retval;
}

static int cortex_a_read_buffer(struct target *target, target_addr_t address,
                                uint32_t count, uint8_t *buffer)
{
        uint32_t size;

        /* Align up to maximum 4 bytes. The loop condition makes sure the next pass
         * will have something to do with the size we leave to it. */
        for (size = 1; size < 4 && count >= size * 2 + (address & size); size *= 2) {
                if (address & size) {
                        int retval = target_read_memory(target, address, size, 1, buffer);
                        if (retval != ERROR_OK)
                                return retval;
                        address += size;
                        count -= size;
                        buffer += size;
                }
        }

        /* Read the data with as large access size as possible. */
        for (; size > 0; size /= 2) {
                uint32_t aligned = count - count % size;
                if (aligned > 0) {
                        int retval = target_read_memory(target, address, size, aligned / size, buffer);
                        if (retval != ERROR_OK)
                                return retval;
                        address += aligned;
                        count -= aligned;
                        buffer += aligned;
                }
        }

        return ERROR_OK;
}

static int cortex_a_write_buffer(struct target *target, target_addr_t address,
                                 uint32_t count, const uint8_t *buffer)
{
        uint32_t size;

        /* Align up to maximum 4 bytes. The loop condition makes sure the next pass
         * will have something to do with the size we leave to it. */
        for (size = 1; size < 4 && count >= size * 2 + (address & size); size *= 2) {
                if (address & size) {
                        int retval = target_write_memory(target, address, size, 1, buffer);
                        if (retval != ERROR_OK)
                                return retval;
                        address += size;
                        count -= size;
                        buffer += size;
                }
        }

        /* Write the data with as large access size as possible. */
        for (; size > 0; size /= 2) {
                uint32_t aligned = count - count % size;
                if (aligned > 0) {
                        int retval = target_write_memory(target, address, size, aligned / size, buffer);
                        if (retval != ERROR_OK)
                                return retval;
                        address += aligned;
                        count -= aligned;
                        buffer += aligned;
                }
        }

        return ERROR_OK;
}

static int cortex_a_handle_target_request(void *priv)
{
        struct target *target = priv;
        struct armv7a_common *armv7a = target_to_armv7a(target);
        int retval;

        if (!target_was_examined(target))
                return ERROR_OK;
        if (!target->dbg_msg_enabled)
                return ERROR_OK;

        if (target->state == TARGET_RUNNING) {
                uint32_t request;
                uint32_t dscr;
                retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                                armv7a->debug_base + CPUDBG_DSCR, &dscr);

                /* check if we have data */
                int64_t then = timeval_ms();
                while ((dscr & DSCR_DTR_TX_FULL) && (retval == ERROR_OK)) {
                        retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                                        armv7a->debug_base + CPUDBG_DTRTX, &request);
                        if (retval == ERROR_OK) {
                                target_request(target, request);
                                retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                                                armv7a->debug_base + CPUDBG_DSCR, &dscr);
                        }
                        if (timeval_ms() > then + 1000) {
                                LOG_ERROR("Timeout waiting for dtr tx full");
                                return ERROR_FAIL;
                        }
                }
        }

        return ERROR_OK;
}

/*
 * Cortex-A target information and configuration
 */

static int cortex_a_examine_first(struct target *target)
{
        struct cortex_a_common *cortex_a = target_to_cortex_a(target);
        struct armv7a_common *armv7a = &cortex_a->armv7a_common;
        struct adiv5_dap *swjdp = armv7a->arm.dap;

        int i;
        int retval = ERROR_OK;
        uint32_t didr, cpuid, dbg_osreg;

        /* Search for the APB-AP - it is needed for access to debug registers */
        retval = dap_find_ap(swjdp, AP_TYPE_APB_AP, &armv7a->debug_ap);
        if (retval != ERROR_OK) {
                LOG_ERROR("Could not find APB-AP for debug access");
                return retval;
        }

        retval = mem_ap_init(armv7a->debug_ap);
        if (retval != ERROR_OK) {
                LOG_ERROR("Could not initialize the APB-AP");
                return retval;
        }

        armv7a->debug_ap->memaccess_tck = 80;

        if (!target->dbgbase_set) {
                uint32_t dbgbase;
                /* Get ROM Table base */
                uint32_t apid;
                int32_t coreidx = target->coreid;
                LOG_DEBUG("%s's dbgbase is not set, trying to detect using the ROM table",
                          target->cmd_name);
                retval = dap_get_debugbase(armv7a->debug_ap, &dbgbase, &apid);
                if (retval != ERROR_OK)
                        return retval;
                /* Lookup 0x15 -- Processor DAP */
                retval = dap_lookup_cs_component(armv7a->debug_ap, dbgbase, 0x15,
                                &armv7a->debug_base, &coreidx);
                if (retval != ERROR_OK) {
                        LOG_ERROR("Can't detect %s's dbgbase from the ROM table; you need to specify it explicitly.",
                                  target->cmd_name);
                        return retval;
                }
                LOG_DEBUG("Detected core %" PRId32 " dbgbase: %08" PRIx32,
                          target->coreid, armv7a->debug_base);
        } else
                armv7a->debug_base = target->dbgbase;

        retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_DIDR, &didr);
        if (retval != ERROR_OK) {
                LOG_DEBUG("Examine %s failed", "DIDR");
                return retval;
        }

        retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                        armv7a->debug_base + CPUDBG_CPUID, &cpuid);
        if (retval != ERROR_OK) {
                LOG_DEBUG("Examine %s failed", "CPUID");
                return retval;
        }

        LOG_DEBUG("didr = 0x%08" PRIx32, didr);
        LOG_DEBUG("cpuid = 0x%08" PRIx32, cpuid);

        cortex_a->didr = didr;
        cortex_a->cpuid = cpuid;

        retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                                    armv7a->debug_base + CPUDBG_PRSR, &dbg_osreg);
        if (retval != ERROR_OK)
                return retval;
        LOG_DEBUG("target->coreid %" PRId32 " DBGPRSR  0x%" PRIx32, target->coreid, dbg_osreg);

        if ((dbg_osreg & PRSR_POWERUP_STATUS) == 0) {
                LOG_ERROR("target->coreid %" PRId32 " powered down!", target->coreid);
                target->state = TARGET_UNKNOWN; /* TARGET_NO_POWER? */
                return ERROR_TARGET_INIT_FAILED;
        }

        if (dbg_osreg & PRSR_STICKY_RESET_STATUS)
                LOG_DEBUG("target->coreid %" PRId32 " was reset!", target->coreid);

        /* Read DBGOSLSR and check if OSLK is implemented */
        retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                                armv7a->debug_base + CPUDBG_OSLSR, &dbg_osreg);
        if (retval != ERROR_OK)
                return retval;
        LOG_DEBUG("target->coreid %" PRId32 " DBGOSLSR 0x%" PRIx32, target->coreid, dbg_osreg);

        /* check if OS Lock is implemented */
        if ((dbg_osreg & OSLSR_OSLM) == OSLSR_OSLM0 || (dbg_osreg & OSLSR_OSLM) == OSLSR_OSLM1) {
                /* check if OS Lock is set */
                if (dbg_osreg & OSLSR_OSLK) {
                        LOG_DEBUG("target->coreid %" PRId32 " OSLock set! Trying to unlock", target->coreid);

                        retval = mem_ap_write_atomic_u32(armv7a->debug_ap,
                                                        armv7a->debug_base + CPUDBG_OSLAR,
                                                        0);
                        if (retval == ERROR_OK)
                                retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                                                        armv7a->debug_base + CPUDBG_OSLSR, &dbg_osreg);

                        /* if we fail to access the register or cannot reset the OSLK bit, bail out */
                        if (retval != ERROR_OK || (dbg_osreg & OSLSR_OSLK) != 0) {
                                LOG_ERROR("target->coreid %" PRId32 " OSLock sticky, core not powered?",
                                                target->coreid);
                                target->state = TARGET_UNKNOWN; /* TARGET_NO_POWER? */
                                return ERROR_TARGET_INIT_FAILED;
                        }
                }
        }

        armv7a->arm.core_type = ARM_MODE_MON;

        /* Avoid recreating the registers cache */
        if (!target_was_examined(target)) {
                retval = cortex_a_dpm_setup(cortex_a, didr);
                if (retval != ERROR_OK)
                        return retval;
        }

        /* Setup Breakpoint Register Pairs */
        cortex_a->brp_num = ((didr >> 24) & 0x0F) + 1;
        cortex_a->brp_num_context = ((didr >> 20) & 0x0F) + 1;
        cortex_a->brp_num_available = cortex_a->brp_num;
        free(cortex_a->brp_list);
        cortex_a->brp_list = calloc(cortex_a->brp_num, sizeof(struct cortex_a_brp));
/*      cortex_a->brb_enabled = ????; */
        for (i = 0; i < cortex_a->brp_num; i++) {
                cortex_a->brp_list[i].used = 0;
                if (i < (cortex_a->brp_num-cortex_a->brp_num_context))
                        cortex_a->brp_list[i].type = BRP_NORMAL;
                else
                        cortex_a->brp_list[i].type = BRP_CONTEXT;
                cortex_a->brp_list[i].value = 0;
                cortex_a->brp_list[i].control = 0;
                cortex_a->brp_list[i].BRPn = i;
        }

        LOG_DEBUG("Configured %i hw breakpoints", cortex_a->brp_num);

        /* select debug_ap as default */
        swjdp->apsel = armv7a->debug_ap->ap_num;

        target_set_examined(target);
        return ERROR_OK;
}

static int cortex_a_examine(struct target *target)
{
        int retval = ERROR_OK;

        /* Reestablish communication after target reset */
        retval = cortex_a_examine_first(target);

        /* Configure core debug access */
        if (retval == ERROR_OK)
                retval = cortex_a_init_debug_access(target);

        return retval;
}

/*
 *      Cortex-A target creation and initialization
 */

static int cortex_a_init_target(struct command_context *cmd_ctx,
        struct target *target)
{
        /* examine_first() does a bunch of this */
        arm_semihosting_init(target);
        return ERROR_OK;
}

static int cortex_a_init_arch_info(struct target *target,
        struct cortex_a_common *cortex_a, struct adiv5_dap *dap)
{
        struct armv7a_common *armv7a = &cortex_a->armv7a_common;

        /* Setup struct cortex_a_common */
        cortex_a->common_magic = CORTEX_A_COMMON_MAGIC;
        armv7a->arm.dap = dap;

        /* register arch-specific functions */
        armv7a->examine_debug_reason = NULL;

        armv7a->post_debug_entry = cortex_a_post_debug_entry;

        armv7a->pre_restore_context = NULL;

        armv7a->armv7a_mmu.read_physical_memory = cortex_a_read_phys_memory;


/*      arm7_9->handle_target_request = cortex_a_handle_target_request; */

        /* REVISIT v7a setup should be in a v7a-specific routine */
        armv7a_init_arch_info(target, armv7a);
        target_register_timer_callback(cortex_a_handle_target_request, 1,
                TARGET_TIMER_TYPE_PERIODIC, target);

        return ERROR_OK;
}

static int cortex_a_target_create(struct target *target, Jim_Interp *interp)
{
        struct cortex_a_common *cortex_a;
        struct adiv5_private_config *pc;

        if (target->private_config == NULL)
                return ERROR_FAIL;

        pc = (struct adiv5_private_config *)target->private_config;

        cortex_a = calloc(1, sizeof(struct cortex_a_common));
        if (cortex_a == NULL) {
                LOG_ERROR("Out of memory");
                return ERROR_FAIL;
        }
        cortex_a->common_magic = CORTEX_A_COMMON_MAGIC;
        cortex_a->armv7a_common.is_armv7r = false;
        cortex_a->armv7a_common.arm.arm_vfp_version = ARM_VFP_V3;

        return cortex_a_init_arch_info(target, cortex_a, pc->dap);
}

static int cortex_r4_target_create(struct target *target, Jim_Interp *interp)
{
        struct cortex_a_common *cortex_a;
        struct adiv5_private_config *pc;

        pc = (struct adiv5_private_config *)target->private_config;
        if (adiv5_verify_config(pc) != ERROR_OK)
                return ERROR_FAIL;

        cortex_a = calloc(1, sizeof(struct cortex_a_common));
        if (cortex_a == NULL) {
                LOG_ERROR("Out of memory");
                return ERROR_FAIL;
        }
        cortex_a->common_magic = CORTEX_A_COMMON_MAGIC;
        cortex_a->armv7a_common.is_armv7r = true;

        return cortex_a_init_arch_info(target, cortex_a, pc->dap);
}

static void cortex_a_deinit_target(struct target *target)
{
        struct cortex_a_common *cortex_a = target_to_cortex_a(target);
        struct armv7a_common *armv7a = &cortex_a->armv7a_common;
        struct arm_dpm *dpm = &armv7a->dpm;
        uint32_t dscr;
        int retval;

        if (target_was_examined(target)) {
                /* Disable halt for breakpoint, watchpoint and vector catch */
                retval = mem_ap_read_atomic_u32(armv7a->debug_ap,
                                armv7a->debug_base + CPUDBG_DSCR, &dscr);
                if (retval == ERROR_OK)
                        mem_ap_write_atomic_u32(armv7a->debug_ap,
                                        armv7a->debug_base + CPUDBG_DSCR,
                                        dscr & ~DSCR_HALT_DBG_MODE);
        }

        free(cortex_a->brp_list);
        free(dpm->dbp);
        free(dpm->dwp);
        free(target->private_config);
        free(cortex_a);
}

static int cortex_a_mmu(struct target *target, int *enabled)
{
        struct armv7a_common *armv7a = target_to_armv7a(target);

        if (target->state != TARGET_HALTED) {
                LOG_ERROR("%s: target not halted", __func__);
                return ERROR_TARGET_INVALID;
        }

        if (armv7a->is_armv7r)
                *enabled = 0;
        else
                *enabled = target_to_cortex_a(target)->armv7a_common.armv7a_mmu.mmu_enabled;

        return ERROR_OK;
}

static int cortex_a_virt2phys(struct target *target,
        target_addr_t virt, target_addr_t *phys)
{
        int retval;
        int mmu_enabled = 0;

        /*
         * If the MMU was not enabled at debug entry, there is no
         * way of knowing if there was ever a valid configuration
         * for it and thus it's not safe to enable it. In this case,
         * just return the virtual address as physical.
         */
        cortex_a_mmu(target, &mmu_enabled);
        if (!mmu_enabled) {
                *phys = virt;
                return ERROR_OK;
        }

        /* mmu must be enable in order to get a correct translation */
        retval = cortex_a_mmu_modify(target, 1);
        if (retval != ERROR_OK)
                return retval;
        return armv7a_mmu_translate_va_pa(target, (uint32_t)virt,
                                                    (uint32_t *)phys, 1);
}

COMMAND_HANDLER(cortex_a_handle_cache_info_command)
{
        struct target *target = get_current_target(CMD_CTX);
        struct armv7a_common *armv7a = target_to_armv7a(target);

        return armv7a_handle_cache_info_command(CMD_CTX,
                        &armv7a->armv7a_mmu.armv7a_cache);
}


COMMAND_HANDLER(cortex_a_handle_dbginit_command)
{
        struct target *target = get_current_target(CMD_CTX);
        if (!target_was_examined(target)) {
                LOG_ERROR("target not examined yet");
                return ERROR_FAIL;
        }

        return cortex_a_init_debug_access(target);
}

COMMAND_HANDLER(handle_cortex_a_mask_interrupts_command)
{
        struct target *target = get_current_target(CMD_CTX);
        struct cortex_a_common *cortex_a = target_to_cortex_a(target);

        static const Jim_Nvp nvp_maskisr_modes[] = {
                { .name = "off", .value = CORTEX_A_ISRMASK_OFF },
                { .name = "on", .value = CORTEX_A_ISRMASK_ON },
                { .name = NULL, .value = -1 },
        };
        const Jim_Nvp *n;

        if (CMD_ARGC > 0) {
                n = Jim_Nvp_name2value_simple(nvp_maskisr_modes, CMD_ARGV[0]);
                if (n->name == NULL) {
                        LOG_ERROR("Unknown parameter: %s - should be off or on", CMD_ARGV[0]);
                        return ERROR_COMMAND_SYNTAX_ERROR;
                }

                cortex_a->isrmasking_mode = n->value;
        }

        n = Jim_Nvp_value2name_simple(nvp_maskisr_modes, cortex_a->isrmasking_mode);
        command_print(CMD_CTX, "cortex_a interrupt mask %s", n->name);

        return ERROR_OK;
}

COMMAND_HANDLER(handle_cortex_a_dacrfixup_command)
{
        struct target *target = get_current_target(CMD_CTX);
        struct cortex_a_common *cortex_a = target_to_cortex_a(target);

        static const Jim_Nvp nvp_dacrfixup_modes[] = {
                { .name = "off", .value = CORTEX_A_DACRFIXUP_OFF },
                { .name = "on", .value = CORTEX_A_DACRFIXUP_ON },
                { .name = NULL, .value = -1 },
        };
        const Jim_Nvp *n;

        if (CMD_ARGC > 0) {
                n = Jim_Nvp_name2value_simple(nvp_dacrfixup_modes, CMD_ARGV[0]);
                if (n->name == NULL)
                        return ERROR_COMMAND_SYNTAX_ERROR;
                cortex_a->dacrfixup_mode = n->value;

        }

        n = Jim_Nvp_value2name_simple(nvp_dacrfixup_modes, cortex_a->dacrfixup_mode);
        command_print(CMD_CTX, "cortex_a domain access control fixup %s", n->name);

        return ERROR_OK;
}

static const struct command_registration cortex_a_exec_command_handlers[] = {
        {
                .name = "cache_info",
                .handler = cortex_a_handle_cache_info_command,
                .mode = COMMAND_EXEC,
                .help = "display information about target caches",
                .usage = "",
        },
        {
                .name = "dbginit",
                .handler = cortex_a_handle_dbginit_command,
                .mode = COMMAND_EXEC,
                .help = "Initialize core debug",
                .usage = "",
        },
        {
                .name = "maskisr",
                .handler = handle_cortex_a_mask_interrupts_command,
                .mode = COMMAND_ANY,
                .help = "mask cortex_a interrupts",
                .usage = "['on'|'off']",
        },
        {
                .name = "dacrfixup",
                .handler = handle_cortex_a_dacrfixup_command,
                .mode = COMMAND_ANY,
                .help = "set domain access control (DACR) to all-manager "
                        "on memory access",
                .usage = "['on'|'off']",
        },
        {
                .chain = armv7a_mmu_command_handlers,
        },
        {
                .chain = smp_command_handlers,
        },

        COMMAND_REGISTRATION_DONE
};
static const struct command_registration cortex_a_command_handlers[] = {
        {
                .chain = arm_command_handlers,
        },
        {
                .chain = armv7a_command_handlers,
        },
        {
                .name = "cortex_a",
                .mode = COMMAND_ANY,
                .help = "Cortex-A command group",
                .usage = "",
                .chain = cortex_a_exec_command_handlers,
        },
        COMMAND_REGISTRATION_DONE
};

struct target_type cortexa_target = {
        .name = "cortex_a",
        .deprecated_name = "cortex_a8",

        .poll = cortex_a_poll,
        .arch_state = armv7a_arch_state,

        .halt = cortex_a_halt,
        .resume = cortex_a_resume,
        .step = cortex_a_step,

        .assert_reset = cortex_a_assert_reset,
        .deassert_reset = cortex_a_deassert_reset,

        /* REVISIT allow exporting VFP3 registers ... */
        .get_gdb_arch = arm_get_gdb_arch,
        .get_gdb_reg_list = arm_get_gdb_reg_list,

        .read_memory = cortex_a_read_memory,
        .write_memory = cortex_a_write_memory,

        .read_buffer = cortex_a_read_buffer,
        .write_buffer = cortex_a_write_buffer,

        .checksum_memory = arm_checksum_memory,
        .blank_check_memory = arm_blank_check_memory,

        .run_algorithm = armv4_5_run_algorithm,

        .add_breakpoint = cortex_a_add_breakpoint,
        .add_context_breakpoint = cortex_a_add_context_breakpoint,
        .add_hybrid_breakpoint = cortex_a_add_hybrid_breakpoint,
        .remove_breakpoint = cortex_a_remove_breakpoint,
        .add_watchpoint = NULL,
        .remove_watchpoint = NULL,

        .commands = cortex_a_command_handlers,
        .target_create = cortex_a_target_create,
        .target_jim_configure = adiv5_jim_configure,
        .init_target = cortex_a_init_target,
        .examine = cortex_a_examine,
        .deinit_target = cortex_a_deinit_target,

        .read_phys_memory = cortex_a_read_phys_memory,
        .write_phys_memory = cortex_a_write_phys_memory,
        .mmu = cortex_a_mmu,
        .virt2phys = cortex_a_virt2phys,
};

static const struct command_registration cortex_r4_exec_command_handlers[] = {
        {
                .name = "dbginit",
                .handler = cortex_a_handle_dbginit_command,
                .mode = COMMAND_EXEC,
                .help = "Initialize core debug",
                .usage = "",
        },
        {
                .name = "maskisr",
                .handler = handle_cortex_a_mask_interrupts_command,
                .mode = COMMAND_EXEC,
                .help = "mask cortex_r4 interrupts",
                .usage = "['on'|'off']",
        },

        COMMAND_REGISTRATION_DONE
};
static const struct command_registration cortex_r4_command_handlers[] = {
        {
                .chain = arm_command_handlers,
        },
        {
                .name = "cortex_r4",
                .mode = COMMAND_ANY,
                .help = "Cortex-R4 command group",
                .usage = "",
                .chain = cortex_r4_exec_command_handlers,
        },
        COMMAND_REGISTRATION_DONE
};

struct target_type cortexr4_target = {
        .name = "cortex_r4",

        .poll = cortex_a_poll,
        .arch_state = armv7a_arch_state,

        .halt = cortex_a_halt,
        .resume = cortex_a_resume,
        .step = cortex_a_step,

        .assert_reset = cortex_a_assert_reset,
        .deassert_reset = cortex_a_deassert_reset,

        /* REVISIT allow exporting VFP3 registers ... */
        .get_gdb_arch = arm_get_gdb_arch,
        .get_gdb_reg_list = arm_get_gdb_reg_list,

        .read_memory = cortex_a_read_phys_memory,
        .write_memory = cortex_a_write_phys_memory,

        .checksum_memory = arm_checksum_memory,
        .blank_check_memory = arm_blank_check_memory,

        .run_algorithm = armv4_5_run_algorithm,

        .add_breakpoint = cortex_a_add_breakpoint,
        .add_context_breakpoint = cortex_a_add_context_breakpoint,
        .add_hybrid_breakpoint = cortex_a_add_hybrid_breakpoint,
        .remove_breakpoint = cortex_a_remove_breakpoint,
        .add_watchpoint = NULL,
        .remove_watchpoint = NULL,

        .commands = cortex_r4_command_handlers,
        .target_create = cortex_r4_target_create,
        .target_jim_configure = adiv5_jim_configure,
        .init_target = cortex_a_init_target,
        .examine = cortex_a_examine,
        .deinit_target = cortex_a_deinit_target,
};