/***************************************************************************
* 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) 2007,2008 Øyvind Harboe *
* oyvind.harboe@zylin.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., *
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
* *
* ARMv7-M Architecture, Application Level Reference Manual *
* ARM DDI 0405C (September 2008) *
* *
***************************************************************************/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "breakpoints.h"
#include "armv7m.h"
#include "algorithm.h"
#include "register.h"
#if 0
#define _DEBUG_INSTRUCTION_EXECUTION_
#endif
/** Maps from enum armv7m_mode (except ARMV7M_MODE_ANY) to name. */
char *armv7m_mode_strings[] =
{
"Thread", "Thread (User)", "Handler",
};
static char *armv7m_exception_strings[] =
{
"", "Reset", "NMI", "HardFault",
"MemManage", "BusFault", "UsageFault", "RESERVED",
"RESERVED", "RESERVED", "RESERVED", "SVCall",
"DebugMonitor", "RESERVED", "PendSV", "SysTick"
};
#ifdef ARMV7_GDB_HACKS
uint8_t armv7m_gdb_dummy_cpsr_value[] = {0, 0, 0, 0};
struct reg armv7m_gdb_dummy_cpsr_reg =
{
.name = "GDB dummy cpsr register",
.value = armv7m_gdb_dummy_cpsr_value,
.dirty = 0,
.valid = 1,
.size = 32,
.arch_info = NULL,
};
#endif
/*
* These registers are not memory-mapped. The ARMv7-M profile includes
* memory mapped registers too, such as for the NVIC (interrupt controller)
* and SysTick (timer) modules; those can mostly be treated as peripherals.
*
* The ARMv6-M profile is almost identical in this respect, except that it
* doesn't include basepri or faultmask registers.
*/
static const struct {
unsigned id;
char *name;
unsigned bits;
} armv7m_regs[] = {
{ ARMV7M_R0, "r0", 32 },
{ ARMV7M_R1, "r1", 32 },
{ ARMV7M_R2, "r2", 32 },
{ ARMV7M_R3, "r3", 32 },
{ ARMV7M_R4, "r4", 32 },
{ ARMV7M_R5, "r5", 32 },
{ ARMV7M_R6, "r6", 32 },
{ ARMV7M_R7, "r7", 32 },
{ ARMV7M_R8, "r8", 32 },
{ ARMV7M_R9, "r9", 32 },
{ ARMV7M_R10, "r10", 32 },
{ ARMV7M_R11, "r11", 32 },
{ ARMV7M_R12, "r12", 32 },
{ ARMV7M_R13, "sp", 32 },
{ ARMV7M_R14, "lr", 32 },
{ ARMV7M_PC, "pc", 32 },
{ ARMV7M_xPSR, "xPSR", 32 },
{ ARMV7M_MSP, "msp", 32 },
{ ARMV7M_PSP, "psp", 32 },
{ ARMV7M_PRIMASK, "primask", 1 },
{ ARMV7M_BASEPRI, "basepri", 8 },
{ ARMV7M_FAULTMASK, "faultmask", 1 },
{ ARMV7M_CONTROL, "control", 2 },
};
#define ARMV7M_NUM_REGS ARRAY_SIZE(armv7m_regs)
/**
* Restores target context using the cache of core registers set up
* by armv7m_build_reg_cache(), calling optional core-specific hooks.
*/
int armv7m_restore_context(struct target *target)
{
int i;
struct armv7m_common *armv7m = target_to_armv7m(target);
LOG_DEBUG(" ");
if (armv7m->pre_restore_context)
armv7m->pre_restore_context(target);
for (i = ARMV7M_NUM_REGS - 1; i >= 0; i--)
{
if (armv7m->core_cache->reg_list[i].dirty)
{
armv7m->write_core_reg(target, i);
}
}
return ERROR_OK;
}
/* Core state functions */
/**
* Maps ISR number (from xPSR) to name.
* Note that while names and meanings for the first sixteen are standardized
* (with zero not a true exception), external interrupts are only numbered.
* They are assigned by vendors, which generally assign different numbers to
* peripherals (such as UART0 or a USB peripheral controller).
*/
char *armv7m_exception_string(int number)
{
static char enamebuf[32];
if ((number < 0) | (number > 511))
return "Invalid exception";
if (number < 16)
return armv7m_exception_strings[number];
sprintf(enamebuf, "External Interrupt(%i)", number - 16);
return enamebuf;
}
static int armv7m_get_core_reg(struct reg *reg)
{
int retval;
struct armv7m_core_reg *armv7m_reg = reg->arch_info;
struct target *target = armv7m_reg->target;
struct armv7m_common *armv7m = target_to_armv7m(target);
if (target->state != TARGET_HALTED)
{
return ERROR_TARGET_NOT_HALTED;
}
retval = armv7m->read_core_reg(target, armv7m_reg->num);
return retval;
}
static int armv7m_set_core_reg(struct reg *reg, uint8_t *buf)
{
struct armv7m_core_reg *armv7m_reg = reg->arch_info;
struct target *target = armv7m_reg->target;
uint32_t value = buf_get_u32(buf, 0, 32);
if (target->state != TARGET_HALTED)
{
return ERROR_TARGET_NOT_HALTED;
}
buf_set_u32(reg->value, 0, 32, value);
reg->dirty = 1;
reg->valid = 1;
return ERROR_OK;
}
static int armv7m_read_core_reg(struct target *target, unsigned num)
{
uint32_t reg_value;
int retval;
struct armv7m_core_reg * armv7m_core_reg;
struct armv7m_common *armv7m = target_to_armv7m(target);
if (num >= ARMV7M_NUM_REGS)
return ERROR_INVALID_ARGUMENTS;
armv7m_core_reg = armv7m->core_cache->reg_list[num].arch_info;
retval = armv7m->load_core_reg_u32(target, armv7m_core_reg->type, armv7m_core_reg->num, ®_value);
buf_set_u32(armv7m->core_cache->reg_list[num].value, 0, 32, reg_value);
armv7m->core_cache->reg_list[num].valid = 1;
armv7m->core_cache->reg_list[num].dirty = 0;
return retval;
}
static int armv7m_write_core_reg(struct target *target, unsigned num)
{
int retval;
uint32_t reg_value;
struct armv7m_core_reg *armv7m_core_reg;
struct armv7m_common *armv7m = target_to_armv7m(target);
if (num >= ARMV7M_NUM_REGS)
return ERROR_INVALID_ARGUMENTS;
reg_value = buf_get_u32(armv7m->core_cache->reg_list[num].value, 0, 32);
armv7m_core_reg = armv7m->core_cache->reg_list[num].arch_info;
retval = armv7m->store_core_reg_u32(target, armv7m_core_reg->type, armv7m_core_reg->num, reg_value);
if (retval != ERROR_OK)
{
LOG_ERROR("JTAG failure");
armv7m->core_cache->reg_list[num].dirty = armv7m->core_cache->reg_list[num].valid;
return ERROR_JTAG_DEVICE_ERROR;
}
LOG_DEBUG("write core reg %i value 0x%" PRIx32 "", num , reg_value);
armv7m->core_cache->reg_list[num].valid = 1;
armv7m->core_cache->reg_list[num].dirty = 0;
return ERROR_OK;
}
/**
* Returns generic ARM userspace registers to GDB.
* GDB doesn't quite understand that most ARMs don't have floating point
* hardware, so this also fakes a set of long-obsolete FPA registers that
* are not used in EABI based software stacks.
*/
int armv7m_get_gdb_reg_list(struct target *target, struct reg **reg_list[], int *reg_list_size)
{
struct armv7m_common *armv7m = target_to_armv7m(target);
int i;
*reg_list_size = 26;
*reg_list = malloc(sizeof(struct reg*) * (*reg_list_size));
/*
* GDB register packet format for ARM:
* - the first 16 registers are r0..r15
* - (obsolete) 8 FPA registers
* - (obsolete) FPA status
* - CPSR
*/
for (i = 0; i < 16; i++)
{
(*reg_list)[i] = &armv7m->core_cache->reg_list[i];
}
for (i = 16; i < 24; i++)
(*reg_list)[i] = &arm_gdb_dummy_fp_reg;
(*reg_list)[24] = &arm_gdb_dummy_fps_reg;
#ifdef ARMV7_GDB_HACKS
/* use dummy cpsr reg otherwise gdb may try and set the thumb bit */
(*reg_list)[25] = &armv7m_gdb_dummy_cpsr_reg;
/* ARMV7M is always in thumb mode, try to make GDB understand this
* if it does not support this arch */
*((char*)armv7m->arm.pc->value) |= 1;
#else
(*reg_list)[25] = &armv7m->core_cache->reg_list[ARMV7M_xPSR];
#endif
return ERROR_OK;
}
/* run to exit point. return error if exit point was not reached. */
static int armv7m_run_and_wait(struct target *target, uint32_t entry_point, int timeout_ms, uint32_t exit_point, struct armv7m_common *armv7m)
{
uint32_t pc;
int retval;
/* This code relies on the target specific resume() and poll()->debug_entry()
* sequence to write register values to the processor and the read them back */
if ((retval = target_resume(target, 0, entry_point, 1, 1)) != ERROR_OK)
{
return retval;
}
retval = target_wait_state(target, TARGET_HALTED, timeout_ms);
/* If the target fails to halt due to the breakpoint, force a halt */
if (retval != ERROR_OK || target->state != TARGET_HALTED)
{
if ((retval = target_halt(target)) != ERROR_OK)
return retval;
if ((retval = target_wait_state(target, TARGET_HALTED, 500)) != ERROR_OK)
{
return retval;
}
return ERROR_TARGET_TIMEOUT;
}
armv7m->load_core_reg_u32(target, ARMV7M_REGISTER_CORE_GP, 15, &pc);
if (pc != exit_point)
{
LOG_DEBUG("failed algoritm halted at 0x%" PRIx32 " ", pc);
return ERROR_TARGET_TIMEOUT;
}
return ERROR_OK;
}
/** Runs a Thumb algorithm in the target. */
int armv7m_run_algorithm(struct target *target,
int num_mem_params, struct mem_param *mem_params,
int num_reg_params, struct reg_param *reg_params,
uint32_t entry_point, uint32_t exit_point,
int timeout_ms, void *arch_info)
{
struct armv7m_common *armv7m = target_to_armv7m(target);
struct armv7m_algorithm *armv7m_algorithm_info = arch_info;
enum armv7m_mode core_mode = armv7m->core_mode;
int retval = ERROR_OK;
uint32_t context[ARMV7M_NUM_REGS];
/* NOTE: armv7m_run_algorithm requires that each algorithm uses a software breakpoint
* at the exit point */
if (armv7m_algorithm_info->common_magic != ARMV7M_COMMON_MAGIC)
{
LOG_ERROR("current target isn't an ARMV7M target");
return ERROR_TARGET_INVALID;
}
if (target->state != TARGET_HALTED)
{
LOG_WARNING("target not halted");
return ERROR_TARGET_NOT_HALTED;
}
/* refresh core register cache */
/* Not needed if core register cache is always consistent with target process state */
for (unsigned i = 0; i < ARMV7M_NUM_REGS; i++)
{
if (!armv7m->core_cache->reg_list[i].valid)
armv7m->read_core_reg(target, i);
context[i] = buf_get_u32(armv7m->core_cache->reg_list[i].value, 0, 32);
}
for (int i = 0; i < num_mem_params; i++)
{
if ((retval = target_write_buffer(target, mem_params[i].address, mem_params[i].size, mem_params[i].value)) != ERROR_OK)
return retval;
}
for (int i = 0; i < num_reg_params; i++)
{
struct reg *reg = register_get_by_name(armv7m->core_cache, reg_params[i].reg_name, 0);
// uint32_t regvalue;
if (!reg)
{
LOG_ERROR("BUG: register '%s' not found", reg_params[i].reg_name);
return ERROR_INVALID_ARGUMENTS;
}
if (reg->size != reg_params[i].size)
{
LOG_ERROR("BUG: register '%s' size doesn't match reg_params[i].size", reg_params[i].reg_name);
return ERROR_INVALID_ARGUMENTS;
}
// regvalue = buf_get_u32(reg_params[i].value, 0, 32);
armv7m_set_core_reg(reg, reg_params[i].value);
}
if (armv7m_algorithm_info->core_mode != ARMV7M_MODE_ANY)
{
LOG_DEBUG("setting core_mode: 0x%2.2x", armv7m_algorithm_info->core_mode);
buf_set_u32(armv7m->core_cache->reg_list[ARMV7M_CONTROL].value,
0, 1, armv7m_algorithm_info->core_mode);
armv7m->core_cache->reg_list[ARMV7M_CONTROL].dirty = 1;
armv7m->core_cache->reg_list[ARMV7M_CONTROL].valid = 1;
}
retval = armv7m_run_and_wait(target, entry_point, timeout_ms, exit_point, armv7m);
if (retval != ERROR_OK)
{
return retval;
}
/* Read memory values to mem_params[] */
for (int i = 0; i < num_mem_params; i++)
{
if (mem_params[i].direction != PARAM_OUT)
if ((retval = target_read_buffer(target, mem_params[i].address, mem_params[i].size, mem_params[i].value)) != ERROR_OK)
{
return retval;
}
}
/* Copy core register values to reg_params[] */
for (int i = 0; i < num_reg_params; i++)
{
if (reg_params[i].direction != PARAM_OUT)
{
struct reg *reg = register_get_by_name(armv7m->core_cache, reg_params[i].reg_name, 0);
if (!reg)
{
LOG_ERROR("BUG: register '%s' not found", reg_params[i].reg_name);
return ERROR_INVALID_ARGUMENTS;
}
if (reg->size != reg_params[i].size)
{
LOG_ERROR("BUG: register '%s' size doesn't match reg_params[i].size", reg_params[i].reg_name);
return ERROR_INVALID_ARGUMENTS;
}
buf_set_u32(reg_params[i].value, 0, 32, buf_get_u32(reg->value, 0, 32));
}
}
for (int i = ARMV7M_NUM_REGS - 1; i >= 0; i--)
{
uint32_t regvalue;
regvalue = buf_get_u32(armv7m->core_cache->reg_list[i].value, 0, 32);
if (regvalue != context[i])
{
LOG_DEBUG("restoring register %s with value 0x%8.8" PRIx32,
armv7m->core_cache->reg_list[i].name, context[i]);
buf_set_u32(armv7m->core_cache->reg_list[i].value,
0, 32, context[i]);
armv7m->core_cache->reg_list[i].valid = 1;
armv7m->core_cache->reg_list[i].dirty = 1;
}
}
armv7m->core_mode = core_mode;
return retval;
}
/** Logs summary of ARMv7-M state for a halted target. */
int armv7m_arch_state(struct target *target)
{
struct armv7m_common *armv7m = target_to_armv7m(target);
struct arm *arm = &armv7m->arm;
uint32_t ctrl, sp;
ctrl = buf_get_u32(armv7m->core_cache->reg_list[ARMV7M_CONTROL].value, 0, 32);
sp = buf_get_u32(armv7m->core_cache->reg_list[ARMV7M_R13].value, 0, 32);
LOG_USER("target halted due to %s, current mode: %s %s\n"
"xPSR: %#8.8" PRIx32 " pc: %#8.8" PRIx32 " %csp: %#8.8" PRIx32 "%s",
debug_reason_name(target),
armv7m_mode_strings[armv7m->core_mode],
armv7m_exception_string(armv7m->exception_number),
buf_get_u32(arm->cpsr->value, 0, 32),
buf_get_u32(arm->pc->value, 0, 32),
(ctrl & 0x02) ? 'p' : 'm',
sp,
arm->is_semihosting ? ", semihosting" : "");
return ERROR_OK;
}
static const struct reg_arch_type armv7m_reg_type = {
.get = armv7m_get_core_reg,
.set = armv7m_set_core_reg,
};
/** Builds cache of architecturally defined registers. */
struct reg_cache *armv7m_build_reg_cache(struct target *target)
{
struct armv7m_common *armv7m = target_to_armv7m(target);
struct arm *arm = &armv7m->arm;
int num_regs = ARMV7M_NUM_REGS;
struct reg_cache **cache_p = register_get_last_cache_p(&target->reg_cache);
struct reg_cache *cache = malloc(sizeof(struct reg_cache));
struct reg *reg_list = calloc(num_regs, sizeof(struct reg));
struct armv7m_core_reg *arch_info = calloc(num_regs, sizeof(struct armv7m_core_reg));
int i;
#ifdef ARMV7_GDB_HACKS
register_init_dummy(&armv7m_gdb_dummy_cpsr_reg);
#endif
/* Build the process context cache */
cache->name = "arm v7m registers";
cache->next = NULL;
cache->reg_list = reg_list;
cache->num_regs = num_regs;
(*cache_p) = cache;
armv7m->core_cache = cache;
for (i = 0; i < num_regs; i++)
{
arch_info[i].num = armv7m_regs[i].id;
arch_info[i].target = target;
arch_info[i].armv7m_common = armv7m;
reg_list[i].name = armv7m_regs[i].name;
reg_list[i].size = armv7m_regs[i].bits;
reg_list[i].value = calloc(1, 4);
reg_list[i].dirty = 0;
reg_list[i].valid = 0;
reg_list[i].type = &armv7m_reg_type;
reg_list[i].arch_info = &arch_info[i];
}
arm->cpsr = reg_list + ARMV7M_xPSR;
arm->pc = reg_list + ARMV7M_PC;
arm->core_cache = cache;
return cache;
}
static int armv7m_setup_semihosting(struct target *target, int enable)
{
/* nothing todo for armv7m */
return ERROR_OK;
}
/** Sets up target as a generic ARMv7-M core */
int armv7m_init_arch_info(struct target *target, struct armv7m_common *armv7m)
{
struct arm *arm = &armv7m->arm;
armv7m->common_magic = ARMV7M_COMMON_MAGIC;
arm->core_type = ARM_MODE_THREAD;
arm->arch_info = armv7m;
arm->setup_semihosting = armv7m_setup_semihosting;
/* FIXME remove v7m-specific r/w core_reg functions;
* use the generic ARM core support..
*/
armv7m->read_core_reg = armv7m_read_core_reg;
armv7m->write_core_reg = armv7m_write_core_reg;
return arm_init_arch_info(target, arm);
}
/** Generates a CRC32 checksum of a memory region. */
int armv7m_checksum_memory(struct target *target,
uint32_t address, uint32_t count, uint32_t* checksum)
{
struct working_area *crc_algorithm;
struct armv7m_algorithm armv7m_info;
struct reg_param reg_params[2];
int retval;
static const uint16_t cortex_m3_crc_code[] = {
0x4602, /* mov r2, r0 */
0xF04F, 0x30FF, /* mov r0, #0xffffffff */
0x460B, /* mov r3, r1 */
0xF04F, 0x0400, /* mov r4, #0 */
0xE013, /* b ncomp */
/* nbyte: */
0x5D11, /* ldrb r1, [r2, r4] */
0xF8DF, 0x7028, /* ldr r7, CRC32XOR */
0xEA80, 0x6001, /* eor r0, r0, r1, asl #24 */
0xF04F, 0x0500, /* mov r5, #0 */
/* loop: */
0x2800, /* cmp r0, #0 */
0xEA4F, 0x0640, /* mov r6, r0, asl #1 */
0xF105, 0x0501, /* add r5, r5, #1 */
0x4630, /* mov r0, r6 */
0xBFB8, /* it lt */
0xEA86, 0x0007, /* eor r0, r6, r7 */
0x2D08, /* cmp r5, #8 */
0xD1F4, /* bne loop */
0xF104, 0x0401, /* add r4, r4, #1 */
/* ncomp: */
0x429C, /* cmp r4, r3 */
0xD1E9, /* bne nbyte */
0xBE00, /* bkpt #0 */
0x1DB7, 0x04C1 /* CRC32XOR: .word 0x04C11DB7 */
};
uint32_t i;
if (target_alloc_working_area(target, sizeof(cortex_m3_crc_code), &crc_algorithm) != ERROR_OK)
{
return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
}
/* convert flash writing code into a buffer in target endianness */
for (i = 0; i < ARRAY_SIZE(cortex_m3_crc_code); i++)
if ((retval = target_write_u16(target, crc_algorithm->address + i*sizeof(uint16_t), cortex_m3_crc_code[i])) != ERROR_OK)
{
return retval;
}
armv7m_info.common_magic = ARMV7M_COMMON_MAGIC;
armv7m_info.core_mode = ARMV7M_MODE_ANY;
init_reg_param(®_params[0], "r0", 32, PARAM_IN_OUT);
init_reg_param(®_params[1], "r1", 32, PARAM_OUT);
buf_set_u32(reg_params[0].value, 0, 32, address);
buf_set_u32(reg_params[1].value, 0, 32, count);
int timeout = 20000 * (1 + (count / (1024 * 1024)));
if ((retval = target_run_algorithm(target, 0, NULL, 2, reg_params,
crc_algorithm->address, crc_algorithm->address + (sizeof(cortex_m3_crc_code)-6), timeout, &armv7m_info)) != ERROR_OK)
{
LOG_ERROR("error executing cortex_m3 crc algorithm");
destroy_reg_param(®_params[0]);
destroy_reg_param(®_params[1]);
target_free_working_area(target, crc_algorithm);
return retval;
}
*checksum = buf_get_u32(reg_params[0].value, 0, 32);
destroy_reg_param(®_params[0]);
destroy_reg_param(®_params[1]);
target_free_working_area(target, crc_algorithm);
return ERROR_OK;
}
/** Checks whether a memory region is zeroed. */
int armv7m_blank_check_memory(struct target *target,
uint32_t address, uint32_t count, uint32_t* blank)
{
struct working_area *erase_check_algorithm;
struct reg_param reg_params[3];
struct armv7m_algorithm armv7m_info;
int retval;
uint32_t i;
static const uint16_t erase_check_code[] =
{
/* loop: */
0xF810, 0x3B01, /* ldrb r3, [r0], #1 */
0xEA02, 0x0203, /* and r2, r2, r3 */
0x3901, /* subs r1, r1, #1 */
0xD1F9, /* bne loop */
0xBE00, /* bkpt #0 */
};
/* make sure we have a working area */
if (target_alloc_working_area(target, sizeof(erase_check_code), &erase_check_algorithm) != ERROR_OK)
{
return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
}
/* convert flash writing code into a buffer in target endianness */
for (i = 0; i < ARRAY_SIZE(erase_check_code); i++)
target_write_u16(target, erase_check_algorithm->address + i*sizeof(uint16_t), erase_check_code[i]);
armv7m_info.common_magic = ARMV7M_COMMON_MAGIC;
armv7m_info.core_mode = ARMV7M_MODE_ANY;
init_reg_param(®_params[0], "r0", 32, PARAM_OUT);
buf_set_u32(reg_params[0].value, 0, 32, address);
init_reg_param(®_params[1], "r1", 32, PARAM_OUT);
buf_set_u32(reg_params[1].value, 0, 32, count);
init_reg_param(®_params[2], "r2", 32, PARAM_IN_OUT);
buf_set_u32(reg_params[2].value, 0, 32, 0xff);
if ((retval = target_run_algorithm(target, 0, NULL, 3, reg_params,
erase_check_algorithm->address, erase_check_algorithm->address + (sizeof(erase_check_code)-2), 10000, &armv7m_info)) != ERROR_OK)
{
destroy_reg_param(®_params[0]);
destroy_reg_param(®_params[1]);
destroy_reg_param(®_params[2]);
target_free_working_area(target, erase_check_algorithm);
return 0;
}
*blank = buf_get_u32(reg_params[2].value, 0, 32);
destroy_reg_param(®_params[0]);
destroy_reg_param(®_params[1]);
destroy_reg_param(®_params[2]);
target_free_working_area(target, erase_check_algorithm);
return ERROR_OK;
}
int armv7m_maybe_skip_bkpt_inst(struct target *target, bool *inst_found)
{
struct armv7m_common *armv7m = target_to_armv7m(target);
struct reg *r = armv7m->arm.pc;
bool result = false;
/* if we halted last time due to a bkpt instruction
* then we have to manually step over it, otherwise
* the core will break again */
if (target->debug_reason == DBG_REASON_BREAKPOINT)
{
uint16_t op;
uint32_t pc = buf_get_u32(r->value, 0, 32);
pc &= ~1;
if (target_read_u16(target, pc, &op) == ERROR_OK)
{
if ((op & 0xFF00) == 0xBE00)
{
pc = buf_get_u32(r->value, 0, 32) + 2;
buf_set_u32(r->value, 0, 32, pc);
r->dirty = true;
r->valid = true;
result = true;
LOG_DEBUG("Skipping over BKPT instruction");
}
}
}
if (inst_found) {
*inst_found = result;
}
return ERROR_OK;
}
const struct command_registration armv7m_command_handlers[] = {
{
.chain = arm_command_handlers,
},
{
.chain = dap_command_handlers,
},
COMMAND_REGISTRATION_DONE
};