[openocd.git] / src / flash / nor / at91sam4l.c

/***************************************************************************
 *   Copyright (C) 2013 by Andrey Yurovsky                                 *
 *   Andrey Yurovsky <yurovsky@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, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.           *
 ***************************************************************************/

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

#include "imp.h"

/* At this time, the SAM4L Flash is available in these capacities:
 * ATSAM4Lx4xx: 256KB (512 pages)
 * ATSAM4Lx2xx: 128KB (256 pages)
 * ATSAM4Lx8xx: 512KB (1024 pages)
 */

/* There are 16 lockable regions regardless of overall capacity.        The number
 * of pages per sector is therefore dependant on capacity. */
#define SAM4L_NUM_SECTORS 16

/* Locations in memory map */
#define SAM4L_FLASH                     0x00000000 /* Flash region */
#define SAM4L_FLASH_USER        0x00800000 /* Flash user page region */
#define SAM4L_FLASHCALW         0x400A0000 /* Flash controller */
#define SAM4L_CHIPID            0x400E0740 /* Chip Identification */

/* Offsets from SAM4L_FLASHCALW */
#define SAM4L_FCR                       0x00 /* Flash Control Register (RW) */
#define SAM4L_FCMD                      0x04 /* Flash Command Register (RW) */
#define SAM4L_FSR                       0x08 /* Flash Status Register (RO) */
#define SAM4L_FPR                       0x0C /* Flash Parameter Register (RO) */
#define SAM4L_FVR                       0x10 /* Flash Version Register (RO) */
#define SAM4L_FGPFRHI           0x14 /* Flash General Purpose Register High (RO) */
#define SAM4L_FGPFRLO           0x18 /* Flash General Purpose Register Low (RO) */

/* Offsets from SAM4L_CHIPID */
#define SAM4L_CIDR                      0x00 /* Chip ID Register (RO) */
#define SAM4L_EXID                      0x04 /* Chip ID Extension Register (RO) */

/* Flash commands (for SAM4L_FCMD), see Table 14-5 */
#define SAM4L_FCMD_NOP          0        /* No Operation */
#define SAM4L_FCMD_WP           1        /* Write Page */
#define SAM4L_FCMD_EP           2        /* Erase Page */
#define SAM4L_FCMD_CPB          3        /* Clear Page Buffer */
#define SAM4L_FCMD_LP           4        /* Lock region containing given page */
#define SAM4L_FCMD_UP           5        /* Unlock region containing given page */
#define SAM4L_FCMD_EA           6        /* Erase All */
#define SAM4L_FCMD_WGPB         7        /* Write general-purpose fuse bit */
#define SAM4L_FCMD_EGPB         8        /* Erase general-purpose fuse bit */
#define SAM4L_FCMD_SSB          9        /* Set security fuses */
#define SAM4L_FCMD_PGPFB        10      /* Program general-purpose fuse byte */
#define SAM4L_FCMD_EAGPF        11      /* Erase all general-purpose fuse bits */
#define SAM4L_FCMD_QPR          12      /* Quick page read */
#define SAM4L_FCMD_WUP          13      /* Write user page */
#define SAM4L_FCMD_EUP          14      /* Erase user page */
#define SAM4L_FCMD_QPRUP        15      /* Quick page read (user page) */
#define SAM4L_FCMD_HSEN         16      /* High speed mode enable */
#define SAM4L_FCMD_HSDIS        17      /* High speed mode disable */

#define SAM4L_FMCD_CMDKEY       0xA5UL  /* 'key' to issue commands, see 14.10.2 */

struct sam4l_chip_info {
        uint32_t id;
        uint32_t exid;
        const char *name;
};

/* These are taken from Table 9-1 in 42023E-SAM-07/2013 */
static const struct sam4l_chip_info sam4l_known_chips[] = {
        { 0xAB0B0AE0, 0x1400000F, "ATSAM4LC8C" },
        { 0xAB0A09E0, 0x0400000F, "ATSAM4LC4C" },
        { 0xAB0A07E0, 0x0400000F, "ATSAM4LC2C" },
        { 0xAB0B0AE0, 0x1300000F, "ATSAM4LC8B" },
        { 0xAB0A09E0, 0x0300000F, "ATSAM4LC4B" },
        { 0xAB0A07E0, 0x0300000F, "ATSAM4LC2B" },
        { 0xAB0B0AE0, 0x1200000F, "ATSAM4LC8A" },
        { 0xAB0A09E0, 0x0200000F, "ATSAM4LC4A" },
        { 0xAB0A07E0, 0x0200000F, "ATSAM4LC2A" },
        { 0xAB0B0AE0, 0x14000002, "ATSAM4LS8C" },
        { 0xAB0A09E0, 0x04000002, "ATSAM4LS4C" },
        { 0xAB0A07E0, 0x04000002, "ATSAM4LS2C" },
        { 0xAB0B0AE0, 0x13000002, "ATSAM4LS8B" },
        { 0xAB0A09E0, 0x03000002, "ATSAM4LS4B" },
        { 0xAB0A07E0, 0x03000002, "ATSAM4LS2B" },
        { 0xAB0B0AE0, 0x12000002, "ATSAM4LS8A" },
        { 0xAB0A09E0, 0x02000002, "ATSAM4LS4A" },
        { 0xAB0A07E0, 0x02000002, "ATSAM4LS2A" },
};

/* Meaning of SRAMSIZ field in CHIPID, see 9.3.1 in 42023E-SAM-07/2013 */
static const uint16_t sam4l_ram_sizes[16] = { 48, 1, 2, 6, 24, 4, 80, 160, 8, 16, 32, 64, 128, 256, 96, 512 };

/* Meaning of PSZ field in FPR, see 14.10.4 in 42023E-SAM-07/2013 */
static const uint16_t sam4l_page_sizes[8] = { 32, 64, 128, 256, 512, 1024, 2048, 4096 };

struct sam4l_info {
        const struct sam4l_chip_info *details;

        uint32_t flash_kb;
        uint32_t ram_kb;
        uint32_t page_size;
        int num_pages;
        int sector_size;
        int pages_per_sector;

        bool probed;
        struct target *target;
        struct sam4l_info *next;
};

static struct sam4l_info *sam4l_chips;

static int sam4l_flash_wait_until_ready(struct target *target)
{
        volatile unsigned int t = 0;
        uint32_t st;
        int res;

        /* Poll the status register until the FRDY bit is set */
        do {
                res = target_read_u32(target, SAM4L_FLASHCALW + SAM4L_FSR, &st);
        } while (res == ERROR_OK && !(st & (1<<0)) && ++t < 10);

        return res;
}

static int sam4l_flash_check_error(struct target *target, uint32_t *err)
{
        uint32_t st;
        int res;

        res = target_read_u32(target, SAM4L_FLASHCALW + SAM4L_FSR, &st);

        if (res == ERROR_OK)
                *err = st & ((1<<3) | (1<<2)); /* grab PROGE and LOCKE bits */

        return res;
}

static int sam4l_flash_command(struct target *target, uint8_t cmd, int page)
{
        int res;
        uint32_t fcmd;
        uint32_t err;

        res = sam4l_flash_wait_until_ready(target);
        if (res != ERROR_OK)
                return res;

        if (page >= 0) {
                /* Set the page number. For some commands, the page number is just an
                 * argument (ex: fuse bit number). */
                fcmd = (SAM4L_FMCD_CMDKEY << 24) | ((page & 0xFFFF) << 8) | (cmd & 0x3F);
        } else {
                /* Reuse the page number that was read from the flash command register. */
                res = target_read_u32(target, SAM4L_FLASHCALW + SAM4L_FCMD, &fcmd);
                if (res != ERROR_OK)
                        return res;

                fcmd &= ~0x3F; /* clear out the command code */
                fcmd |= (SAM4L_FMCD_CMDKEY << 24) | (cmd & 0x3F);
        }

        /* Send the command */
        res = target_write_u32(target, SAM4L_FLASHCALW + SAM4L_FCMD, fcmd);
        if (res != ERROR_OK)
                return res;

        res = sam4l_flash_check_error(target, &err);
        if (res != ERROR_OK)
                return res;

        if (err != 0)
                LOG_ERROR("%s got error status 0x%08" PRIx32, __func__, err);

        res = sam4l_flash_wait_until_ready(target);

        return res;
}

FLASH_BANK_COMMAND_HANDLER(sam4l_flash_bank_command)
{
        struct sam4l_info *chip = sam4l_chips;

        while (chip) {
                if (chip->target == bank->target)
                        break;
                chip = chip->next;
        }

        if (!chip) {
                /* Create a new chip */
                chip = calloc(1, sizeof(*chip));
                if (!chip)
                        return ERROR_FAIL;

                chip->target = bank->target;
                chip->probed = false;

                bank->driver_priv = chip;

                /* Insert it into the chips list (at head) */
                chip->next = sam4l_chips;
                sam4l_chips = chip;
        }

        if (bank->base != SAM4L_FLASH) {
                LOG_ERROR("Address 0x%08" PRIx32 " invalid bank address (try 0x%08" PRIx32
                                "[at91sam4l series] )",
                                bank->base, SAM4L_FLASH);
                return ERROR_FAIL;
        }

        return ERROR_OK;
}

static const struct sam4l_chip_info *sam4l_find_chip_name(uint32_t id, uint32_t exid)
{
        unsigned int i;

        id &= ~0xF;

        for (i = 0; i < ARRAY_SIZE(sam4l_known_chips); i++) {
                if (sam4l_known_chips[i].id == id && sam4l_known_chips[i].exid == exid)
                        return &sam4l_known_chips[i];
        }

        return NULL;
}

static int sam4l_check_page_erased(struct flash_bank *bank, uint32_t pn,
                bool *is_erased_p)
{
        int res;
        uint32_t st;

        /* Issue a quick page read to verify that we've erased this page */
        res = sam4l_flash_command(bank->target, SAM4L_FCMD_QPR, pn);
        if (res != ERROR_OK) {
                LOG_ERROR("Quick page read %d failed", pn);
                return res;
        }

        /* Retrieve the flash status */
        res = target_read_u32(bank->target, SAM4L_FLASHCALW + SAM4L_FSR, &st);
        if (res != ERROR_OK) {
                LOG_ERROR("Couldn't read erase status");
                return res;
        }

        /* Is the page in question really erased? */
        *is_erased_p = !!(st & (1<<5));

        return ERROR_OK;
}

static int sam4l_probe(struct flash_bank *bank)
{
        uint32_t id, exid, param;
        int res;
        struct sam4l_info *chip = (struct sam4l_info *)bank->driver_priv;

        if (chip->probed)
                return ERROR_OK;

        res = target_read_u32(bank->target, SAM4L_CHIPID + SAM4L_CIDR, &id);
        if (res != ERROR_OK) {
                LOG_ERROR("Couldn't read chip ID");
                return res;
        }

        res = target_read_u32(bank->target, SAM4L_CHIPID + SAM4L_EXID, &exid);
        if (res != ERROR_OK) {
                LOG_ERROR("Couldn't read extended chip ID");
                return res;
        }

        chip->details = sam4l_find_chip_name(id, exid);

        /* The RAM capacity is in a lookup table. */
        chip->ram_kb = sam4l_ram_sizes[0xF & (id >> 16)];

        switch (0xF & (id >> 8)) {
                case 0x07:
                        chip->flash_kb = 128;
                        break;
                case 0x09:
                        chip->flash_kb = 256;
                        break;
                case 0x0A:
                        chip->flash_kb = 512;
                        break;
                default:
                        LOG_ERROR("Unknown flash size (chip ID is %08X), assuming 128K", id);
                        chip->flash_kb = 128;
                        break;
        }

        /* Retrieve the Flash parameters */
        res = target_read_u32(bank->target, SAM4L_FLASHCALW + SAM4L_FPR, &param);
        if (res != ERROR_OK) {
                LOG_ERROR("Couldn't read Flash parameters");
                return res;
        }

        /* Fetch the page size from the parameter register.     Technically the flash
         * capacity is there too though the manual mentions that not all parts will
         * have it set so we use the Chip ID capacity information instead. */
        chip->page_size = sam4l_page_sizes[0x7 & (param >> 8)];
        assert(chip->page_size);
        chip->num_pages = chip->flash_kb * 1024 / chip->page_size;

        chip->sector_size = (chip->flash_kb * 1024) / SAM4L_NUM_SECTORS;
        chip->pages_per_sector = chip->sector_size / chip->page_size;

        /* Make sure the bank size is correct */
        bank->size = chip->flash_kb * 1024;

        /* Allocate the sector table. */
        bank->num_sectors = SAM4L_NUM_SECTORS;
        bank->sectors = calloc(bank->num_sectors, (sizeof((bank->sectors)[0])));
        if (!bank->sectors)
                return ERROR_FAIL;

        /* Fill out the sector information: all SAM4L sectors are the same size and
         * there is always a fixed number of them. */
        for (int i = 0; i < bank->num_sectors; i++) {
                bank->sectors[i].size = chip->sector_size;
                bank->sectors[i].offset = i * chip->sector_size;
                /* mark as unknown */
                bank->sectors[i].is_erased = -1;
                bank->sectors[i].is_protected = -1;
        }

        /* Done */
        chip->probed = true;

        LOG_INFO("SAM4L MCU: %s (Rev %c) (%uKB Flash with %d %dB pages, %uKB RAM)",
                        chip->details ? chip->details->name : "unknown", 'A' + (id & 0xF),
                        chip->flash_kb, chip->num_pages, chip->page_size, chip->ram_kb);

        return ERROR_OK;
}

static int sam4l_protect_check(struct flash_bank *bank)
{
        int res;
        uint32_t st;
        struct sam4l_info *chip = (struct sam4l_info *)bank->driver_priv;

        if (bank->target->state != TARGET_HALTED) {
                LOG_ERROR("Target not halted");

                return ERROR_TARGET_NOT_HALTED;
        }

        if (!chip->probed) {
                if (sam4l_probe(bank) != ERROR_OK)
                        return ERROR_FLASH_BANK_NOT_PROBED;
        }

        res = target_read_u32(bank->target, SAM4L_FLASHCALW + SAM4L_FSR, &st);
        if (res != ERROR_OK)
                return res;

        st >>= 16; /* There are 16 lock region bits in the upper half word */
        for (int i = 0; i < bank->num_sectors; i++)
                        bank->sectors[i].is_protected = !!(st & (1<<i));

        return ERROR_OK;
}

static int sam4l_protect(struct flash_bank *bank, int set, int first, int last)
{
        struct sam4l_info *chip = sam4l_chips;

        if (bank->target->state != TARGET_HALTED) {
                LOG_ERROR("Target not halted");

                return ERROR_TARGET_NOT_HALTED;
        }

        if (!chip->probed) {
                if (sam4l_probe(bank) != ERROR_OK)
                        return ERROR_FLASH_BANK_NOT_PROBED;
        }

        /* Make sure the pages make sense. */
        if (first >= bank->num_sectors || last >= bank->num_sectors) {
                LOG_ERROR("Protect range %d - %d not valid (%d sectors total)", first, last,
                                bank->num_sectors);
                return ERROR_FAIL;
        }

        /* Try to lock or unlock each sector in the range.      This is done by locking
         * a region containing one page in that sector, we arbitrarily choose the 0th
         * page in the sector. */
        for (int i = first; i <= last; i++) {
                int res;

                res = sam4l_flash_command(bank->target,
                                set ? SAM4L_FCMD_LP : SAM4L_FCMD_UP, i * chip->pages_per_sector);
                if (res != ERROR_OK) {
                        LOG_ERROR("Can't %slock region containing page %d", set ? "" : "un", i);
                        return res;
                }
        }

        return ERROR_OK;
}

static int sam4l_erase(struct flash_bank *bank, int first, int last)
{
        int ret;
        struct sam4l_info *chip = (struct sam4l_info *)bank->driver_priv;

        if (bank->target->state != TARGET_HALTED) {
                LOG_ERROR("Target not halted");

                return ERROR_TARGET_NOT_HALTED;
        }

        if (!chip->probed) {
                if (sam4l_probe(bank) != ERROR_OK)
                        return ERROR_FLASH_BANK_NOT_PROBED;
        }

        /* Make sure the pages make sense. */
        if (first >= bank->num_sectors || last >= bank->num_sectors) {
                LOG_ERROR("Erase range %d - %d not valid (%d sectors total)", first, last,
                                bank->num_sectors);
                return ERROR_FAIL;
        }

        /* Erase */
        if ((first == 0) && ((last + 1) == bank->num_sectors)) {
                LOG_DEBUG("Erasing the whole chip");

                ret = sam4l_flash_command(bank->target, SAM4L_FCMD_EA, -1);
                if (ret != ERROR_OK) {
                        LOG_ERROR("Erase All failed");
                        return ret;
                }
        } else {
                LOG_DEBUG("Erasing sectors %d through %d...\n", first, last);

                /* For each sector... */
                for (int i = first; i <= last; i++) {
                        /* For each page in that sector... */
                        for (int j = 0; j < chip->pages_per_sector; j++) {
                                int pn = i * chip->pages_per_sector + j;
                                bool is_erased = false;

                                /* Issue the page erase */
                                ret = sam4l_flash_command(bank->target, SAM4L_FCMD_EP, pn);
                                if (ret != ERROR_OK) {
                                        LOG_ERROR("Erasing page %d failed", pn);
                                        return ret;
                                }

                                ret = sam4l_check_page_erased(bank, pn, &is_erased);
                                if (ret != ERROR_OK)
                                        return ret;

                                if (!is_erased) {
                                        LOG_DEBUG("Page %d was not erased.", pn);
                                        return ERROR_FAIL;
                                }
                        }

                        /* This sector is definitely erased. */
                        bank->sectors[i].is_erased = 1;
                }
        }

        return ERROR_OK;
}

/* Write an entire page from host buffer 'buf' to page-aligned 'address' in the
 * Flash. */
static int sam4l_write_page(struct sam4l_info *chip, struct target *target,
                uint32_t address, const uint8_t *buf)
{
        int res;

        /* Clear the page buffer before we write to it */
        res = sam4l_flash_command(target, SAM4L_FCMD_CPB, -1);
        if (res != ERROR_OK) {
                LOG_ERROR("%s: can't clear page buffer", __func__);
                return res;
        }

        /* Write the modified page back to the target's page buffer */
        res = target_write_memory(target, address, 4, chip->page_size / 4, buf);

        if (res != ERROR_OK) {
                LOG_ERROR("%s: %d", __func__, __LINE__);
                return res;
        }

        /* Commit the page contents to Flash: erase the current page and then
         * write it out. */
        res = sam4l_flash_command(target, SAM4L_FCMD_EP, -1);
        if (res != ERROR_OK)
                return res;
        res = sam4l_flash_command(target, SAM4L_FCMD_WP, -1);

        return res;
}

/* Write partial contents into page-aligned 'address' on the Flash from host
 * buffer 'buf' by writing 'nb' of 'buf' at 'offset' into the Flash page. */
static int sam4l_write_page_partial(struct sam4l_info *chip,
                struct flash_bank *bank, uint32_t address, const uint8_t *buf,
                uint32_t page_offset, uint32_t nb)
{
        int res;
        uint8_t *pg = malloc(chip->page_size);
        if (!pg)
                return ERROR_FAIL;

        assert(page_offset + nb < chip->page_size);
        assert((address % chip->page_size) == 0);

        /* Retrieve the full page contents from Flash */
        res = target_read_memory(bank->target, address, 4,
                        chip->page_size / 4, pg);
        if (res != ERROR_OK) {
                free(pg);
                return res;
        }

        /* Insert our partial page over the data from Flash */
        memcpy(pg + (page_offset % chip->page_size), buf, nb);

        /* Write the page back out */
        res = sam4l_write_page(chip, bank->target, address, pg);
        free(pg);

        return res;
}

static int sam4l_write(struct flash_bank *bank, const uint8_t *buffer,
                uint32_t offset, uint32_t count)
{
        int res;
        uint32_t nb = 0;
        struct sam4l_info *chip = (struct sam4l_info *)bank->driver_priv;

        if (bank->target->state != TARGET_HALTED) {
                LOG_ERROR("Target not halted");

                return ERROR_TARGET_NOT_HALTED;
        }

        if (!chip->probed) {
                if (sam4l_probe(bank) != ERROR_OK)
                        return ERROR_FLASH_BANK_NOT_PROBED;
        }

        if (offset % chip->page_size) {
                /* We're starting at an unaligned offset so we'll write a partial page
                 * comprising that offset and up to the end of that page. */
                nb = chip->page_size - (offset % chip->page_size);
                if (nb > count)
                        nb = count;
        } else if (count < chip->page_size) {
                /* We're writing an aligned but partial page. */
                nb = count;
        }

        if (nb > 0) {
                res = sam4l_write_page_partial(chip, bank,
                                (offset / chip->page_size) * chip->page_size + bank->base,
                                buffer,
                                offset % chip->page_size, nb);
                if (res != ERROR_OK)
                        return res;

                /* We're done with the page contents */
                count -= nb;
                offset += nb;
        }

        /* There's at least one aligned page to write out. */
        if (count >= chip->page_size) {
                int np = count / chip->page_size + ((count % chip->page_size) ? 1 : 0);

                for (int i = 0; i < np; i++) {
                        if (count >= chip->page_size) {
                                res = sam4l_write_page(chip, bank->target,
                                                bank->base + (i * chip->page_size),
                                                buffer + (i * chip->page_size));
                                /* Advance one page */
                                offset += chip->page_size;
                                count -= chip->page_size;
                        } else {
                                res = sam4l_write_page_partial(chip, bank,
                                                bank->base + (i * chip->page_size),
                                                buffer + (i * chip->page_size), 0, count);
                                /* We're done after this. */
                                offset += count;
                                count = 0;
                        }

                        if (res != ERROR_OK)
                                return res;
                }
        }

        return ERROR_OK;
}

COMMAND_HANDLER(sam4l_handle_info_command)
{
        return ERROR_OK;
}

static const struct command_registration at91sam4l_exec_command_handlers[] = {
        {
                .name = "info",
                .handler = sam4l_handle_info_command,
                .mode = COMMAND_EXEC,
                .help = "Print information about the current at91sam4l chip"
                        "and its flash configuration.",
        },
        COMMAND_REGISTRATION_DONE
};
static const struct command_registration at91sam4l_command_handlers[] = {
        {
                .name = "at91sam4l",
                .mode = COMMAND_ANY,
                .help = "at91sam4l flash command group",
                .usage = "",
                .chain = at91sam4l_exec_command_handlers,
        },
        COMMAND_REGISTRATION_DONE
};

struct flash_driver at91sam4l_flash = {
        .name = "at91sam4l",
        .commands = at91sam4l_command_handlers,
        .flash_bank_command = sam4l_flash_bank_command,
        .erase = sam4l_erase,
        .protect = sam4l_protect,
        .write = sam4l_write,
        .read = default_flash_read,
        .probe = sam4l_probe,
        .auto_probe = sam4l_probe,
        .erase_check = default_flash_blank_check,
        .protect_check = sam4l_protect_check,
};