src/target/semihosting_common.h

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2
   3 /***************************************************************************
   4  *   Copyright (C) 2018 by Liviu Ionescu                                   *
   5  *   <ilg@livius.net>                                                      *
   6  *                                                                         *
   7  *   Copyright (C) 2009 by Marvell Technology Group Ltd.                   *
   8  *   Written by Nicolas Pitre <nico@marvell.com>                           *
   9  ***************************************************************************/
  10
  11 #ifndef OPENOCD_TARGET_SEMIHOSTING_COMMON_H
  12 #define OPENOCD_TARGET_SEMIHOSTING_COMMON_H
  13
  14 #include <stdint.h>
  15 #include <stdbool.h>
  16 #include <time.h>
  17 #include "helper/replacements.h"
  18 #include <server/server.h>
  19
  20 /*
  21  * According to:
  22  * "Semihosting for AArch32 and AArch64, Release 2.0"
  23  * https://static.docs.arm.com/100863/0200/semihosting.pdf
  24  * from ARM Ltd.
  25  *
  26  * The available semihosting operation numbers passed in R0 are allocated
  27  * as follows:
  28  * - 0x00-0x31 Used by ARM.
  29  * - 0x32-0xFF Reserved for future use by ARM.
  30  * - 0x100-0x1FF Reserved for user applications. These are not used by ARM.
  31  *   However, if you are writing your own SVC operations, you are advised
  32  *   to use a different SVC number rather than using the semihosted
  33  *   SVC number and these operation type numbers.
  34  * - 0x200-0xFFFFFFFF Undefined and currently unused. It is recommended
  35  *   that you do not use these.
  36  */
  37
  38 enum semihosting_operation_numbers {
  39         /*
  40          * ARM semihosting operations, in lexicographic order.
  41          */
  42         SEMIHOSTING_ENTER_SVC = 0x17,   /* DEPRECATED */
  43
  44         SEMIHOSTING_SYS_CLOSE = 0x02,
  45         SEMIHOSTING_SYS_CLOCK = 0x10,
  46         SEMIHOSTING_SYS_ELAPSED = 0x30,
  47         SEMIHOSTING_SYS_ERRNO = 0x13,
  48         SEMIHOSTING_SYS_EXIT = 0x18,
  49         SEMIHOSTING_SYS_EXIT_EXTENDED = 0x20,
  50         SEMIHOSTING_SYS_FLEN = 0x0C,
  51         SEMIHOSTING_SYS_GET_CMDLINE = 0x15,
  52         SEMIHOSTING_SYS_HEAPINFO = 0x16,
  53         SEMIHOSTING_SYS_ISERROR = 0x08,
  54         SEMIHOSTING_SYS_ISTTY = 0x09,
  55         SEMIHOSTING_SYS_OPEN = 0x01,
  56         SEMIHOSTING_SYS_READ = 0x06,
  57         SEMIHOSTING_SYS_READC = 0x07,
  58         SEMIHOSTING_SYS_REMOVE = 0x0E,
  59         SEMIHOSTING_SYS_RENAME = 0x0F,
  60         SEMIHOSTING_SYS_SEEK = 0x0A,
  61         SEMIHOSTING_SYS_SYSTEM = 0x12,
  62         SEMIHOSTING_SYS_TICKFREQ = 0x31,
  63         SEMIHOSTING_SYS_TIME = 0x11,
  64         SEMIHOSTING_SYS_TMPNAM = 0x0D,
  65         SEMIHOSTING_SYS_WRITE = 0x05,
  66         SEMIHOSTING_SYS_WRITEC = 0x03,
  67         SEMIHOSTING_SYS_WRITE0 = 0x04,
  68         SEMIHOSTING_USER_CMD_0X100 = 0x100, /* First user cmd op code */
  69         SEMIHOSTING_USER_CMD_0X107 = 0x107, /* Last supported user cmd op code */
  70         SEMIHOSTING_USER_CMD_0X1FF = 0x1FF, /* Last user cmd op code */
  71 };
  72
  73 /** Maximum allowed Tcl command segment length in bytes*/
  74 #define SEMIHOSTING_MAX_TCL_COMMAND_FIELD_LENGTH (1024 * 1024)
  75
  76 /*
  77  * Codes used by SEMIHOSTING_SYS_EXIT (formerly
  78  * SEMIHOSTING_REPORT_EXCEPTION).
  79  * On 64-bits, the exit code is passed explicitly.
  80  */
  81 enum semihosting_reported_exceptions {
  82         /* On 32 bits, use it for exit(0) */
  83         ADP_STOPPED_APPLICATION_EXIT = ((2 << 16) + 38),
  84         /* On 32 bits, use it for exit(1) */
  85         ADP_STOPPED_RUN_TIME_ERROR = ((2 << 16) + 35),
  86 };
  87
  88 enum semihosting_redirect_config {
  89         SEMIHOSTING_REDIRECT_CFG_NONE,
  90         SEMIHOSTING_REDIRECT_CFG_DEBUG,
  91         SEMIHOSTING_REDIRECT_CFG_STDIO,
  92         SEMIHOSTING_REDIRECT_CFG_ALL,
  93 };
  94
  95 enum semihosting_result {
  96         SEMIHOSTING_NONE,               /* Not halted for a semihosting call. */
  97         SEMIHOSTING_HANDLED,    /* Call handled, and target was resumed. */
  98         SEMIHOSTING_WAITING,    /* Call handled, target is halted waiting until we can resume. */
  99         SEMIHOSTING_ERROR               /* Something went wrong. */
 100 };
 101
 102 struct target;
 103
 104 /*
 105  * A pointer to this structure was added to the target structure.
 106  */
 107 struct semihosting {
 108
 109         /** A flag reporting whether semihosting is active. */
 110         bool is_active;
 111
 112         /** Semihosting STDIO file descriptors */
 113         int stdin_fd, stdout_fd, stderr_fd;
 114
 115         /** redirection configuration, NONE by default */
 116         enum semihosting_redirect_config redirect_cfg;
 117
 118         /** Handle to redirect semihosting print via tcp */
 119         struct connection *tcp_connection;
 120
 121         /** A flag reporting whether semihosting fileio is active. */
 122         bool is_fileio;
 123
 124         /** A flag reporting whether semihosting fileio operation is active. */
 125         bool hit_fileio;
 126
 127         /** Most are resumable, except the two exit calls. */
 128         bool is_resumable;
 129
 130         /**
 131          * When SEMIHOSTING_SYS_EXIT is called outside a debug session,
 132          * things are simple, the openocd process calls exit() and passes
 133          * the value returned by the target.
 134          * When SEMIHOSTING_SYS_EXIT is called during a debug session,
 135          * by default execution returns to the debugger, leaving the
 136          * debugger in a HALT state, similar to the state entered when
 137          * encountering a break.
 138          * In some use cases, it is useful to have SEMIHOSTING_SYS_EXIT
 139          * return normally, as any semihosting call, and do not break
 140          * to the debugger.
 141          * The standard allows this to happen, but the condition
 142          * to trigger it is a bit obscure ("by performing an RDI_Execute
 143          * request or equivalent").
 144          *
 145          * To make the SEMIHOSTING_SYS_EXIT call return normally, enable
 146          * this variable via the dedicated command (default: disabled).
 147          */
 148         bool has_resumable_exit;
 149
 150         /** The Target (hart) word size; 8 for 64-bits targets. */
 151         size_t word_size_bytes;
 152
 153         /** The current semihosting operation (R0 on ARM). */
 154         int op;
 155
 156         /** The current semihosting parameter (R1 or ARM). */
 157         uint64_t param;
 158
 159         /**
 160          * The current semihosting result to be returned to the application.
 161          * Usually 0 for success, -1 for error,
 162          * but sometimes a useful value, even a pointer.
 163          */
 164         int64_t result;
 165
 166         /** The value to be returned by semihosting SYS_ERRNO request. */
 167         int sys_errno;
 168
 169         /** The semihosting command line to be passed to the target. */
 170         char *cmdline;
 171
 172         /** The current time when 'execution starts' */
 173         clock_t setup_time;
 174
 175         /** Base directory for semihosting I/O operations. */
 176         char *basedir;
 177
 178         /**
 179          * Target's extension of semihosting user commands.
 180          * @returns ERROR_NOT_IMPLEMENTED when user command is not handled, otherwise
 181          * sets semihosting->result and semihosting->sys_errno and returns ERROR_OK.
 182          */
 183         int (*user_command_extension)(struct target *target);
 184
 185         int (*setup)(struct target *target, int enable);
 186         int (*post_result)(struct target *target);
 187 };
 188
 189 int semihosting_common_init(struct target *target, void *setup,
 190         void *post_result);
 191 int semihosting_common(struct target *target);
 192
 193 /* utility functions which may also be used by semihosting extensions (custom vendor-defined syscalls) */
 194 int semihosting_read_fields(struct target *target, size_t number,
 195         uint8_t *fields);
 196 int semihosting_write_fields(struct target *target, size_t number,
 197         uint8_t *fields);
 198 uint64_t semihosting_get_field(struct target *target, size_t index,
 199         uint8_t *fields);
 200 void semihosting_set_field(struct target *target, uint64_t value,
 201         size_t index,
 202         uint8_t *fields);
 203
 204 extern const struct command_registration semihosting_common_handlers[];
 205
 206 #endif  /* OPENOCD_TARGET_SEMIHOSTING_COMMON_H */