armv7m.c

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// SPDX-License-Identifier: GPL-2.0-or-later
 
/***************************************************************************
 *   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                                               *
 *                                                                         *
 *   Copyright (C) 2018 by Liviu Ionescu                                   *
 *   <ilg@livius.net>                                                      *
 *                                                                         *
 *   Copyright (C) 2019 by Tomas Vanek                                     *
 *   vanekt@fbl.cz                                                         *
 *                                                                         *
 *   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"
#include "semihosting_common.h"
#include <helper/log.h>
#include <helper/binarybuffer.h>
 
#if 0
#define _DEBUG_INSTRUCTION_EXECUTION_
#endif
 
static const char * const armv7m_exception_strings[] = {
    "", "Reset", "NMI", "HardFault",
    "MemManage", "BusFault", "UsageFault", "SecureFault",
    "RESERVED", "RESERVED", "RESERVED", "SVCall",
    "DebugMonitor", "RESERVED", "PendSV", "SysTick"
};
 
/* PSP is used in some thread modes */
const int armv7m_psp_reg_map[ARMV7M_NUM_CORE_REGS] = {
    ARMV7M_R0, ARMV7M_R1, ARMV7M_R2, ARMV7M_R3,
    ARMV7M_R4, ARMV7M_R5, ARMV7M_R6, ARMV7M_R7,
    ARMV7M_R8, ARMV7M_R9, ARMV7M_R10, ARMV7M_R11,
    ARMV7M_R12, ARMV7M_PSP, ARMV7M_R14, ARMV7M_PC,
    ARMV7M_XPSR,
};
 
/* MSP is used in handler and some thread modes */
const int armv7m_msp_reg_map[ARMV7M_NUM_CORE_REGS] = {
    ARMV7M_R0, ARMV7M_R1, ARMV7M_R2, ARMV7M_R3,
    ARMV7M_R4, ARMV7M_R5, ARMV7M_R6, ARMV7M_R7,
    ARMV7M_R8, ARMV7M_R9, ARMV7M_R10, ARMV7M_R11,
    ARMV7M_R12, ARMV7M_MSP, ARMV7M_R14, ARMV7M_PC,
    ARMV7M_XPSR,
};
 
static struct reg_data_type_bitfield armv8m_vpr_bits[] = {
    {  0, 15, REG_TYPE_UINT },
    { 16, 19, REG_TYPE_UINT },
    { 20, 23, REG_TYPE_UINT },
};
 
static struct reg_data_type_flags_field armv8m_vpr_fields[] = {
    { "P0",     armv8m_vpr_bits + 0, armv8m_vpr_fields + 1, },
    { "MASK01", armv8m_vpr_bits + 1, armv8m_vpr_fields + 2, },
    { "MASK23", armv8m_vpr_bits + 2, NULL },
};
 
static struct reg_data_type_flags armv8m_vpr_flags[] = {
    { 4, armv8m_vpr_fields },
};
 
static struct reg_data_type armv8m_flags_vpr[] = {
    { REG_TYPE_ARCH_DEFINED, "vpr_reg", REG_TYPE_CLASS_FLAGS,
        { .reg_type_flags = armv8m_vpr_flags },
    },
};
 
/*
 * 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 int id;
    const char *name;
    unsigned int bits;
    enum reg_type type;
    const char *group;
    const char *feature;
    struct reg_data_type *data_type;
} armv7m_regs[] = {
    { ARMV7M_R0, "r0", 32, REG_TYPE_INT, "general", "org.gnu.gdb.arm.m-profile", NULL, },
    { ARMV7M_R1, "r1", 32, REG_TYPE_INT, "general", "org.gnu.gdb.arm.m-profile", NULL, },
    { ARMV7M_R2, "r2", 32, REG_TYPE_INT, "general", "org.gnu.gdb.arm.m-profile", NULL, },
    { ARMV7M_R3, "r3", 32, REG_TYPE_INT, "general", "org.gnu.gdb.arm.m-profile", NULL, },
    { ARMV7M_R4, "r4", 32, REG_TYPE_INT, "general", "org.gnu.gdb.arm.m-profile", NULL, },
    { ARMV7M_R5, "r5", 32, REG_TYPE_INT, "general", "org.gnu.gdb.arm.m-profile", NULL, },
    { ARMV7M_R6, "r6", 32, REG_TYPE_INT, "general", "org.gnu.gdb.arm.m-profile", NULL, },
    { ARMV7M_R7, "r7", 32, REG_TYPE_INT, "general", "org.gnu.gdb.arm.m-profile", NULL, },
    { ARMV7M_R8, "r8", 32, REG_TYPE_INT, "general", "org.gnu.gdb.arm.m-profile", NULL, },
    { ARMV7M_R9, "r9", 32, REG_TYPE_INT, "general", "org.gnu.gdb.arm.m-profile", NULL, },
    { ARMV7M_R10, "r10", 32, REG_TYPE_INT, "general", "org.gnu.gdb.arm.m-profile", NULL, },
    { ARMV7M_R11, "r11", 32, REG_TYPE_INT, "general", "org.gnu.gdb.arm.m-profile", NULL, },
    { ARMV7M_R12, "r12", 32, REG_TYPE_INT, "general", "org.gnu.gdb.arm.m-profile", NULL, },
    { ARMV7M_R13, "sp", 32, REG_TYPE_DATA_PTR, "general", "org.gnu.gdb.arm.m-profile", NULL, },
    { ARMV7M_R14, "lr", 32, REG_TYPE_INT, "general", "org.gnu.gdb.arm.m-profile", NULL, },
    { ARMV7M_PC, "pc", 32, REG_TYPE_CODE_PTR, "general", "org.gnu.gdb.arm.m-profile", NULL, },
    { ARMV7M_XPSR, "xpsr", 32, REG_TYPE_INT, "general", "org.gnu.gdb.arm.m-profile", NULL, },
 
    { ARMV7M_MSP, "msp", 32, REG_TYPE_DATA_PTR, "system", "org.gnu.gdb.arm.m-system", NULL, },
    { ARMV7M_PSP, "psp", 32, REG_TYPE_DATA_PTR, "system", "org.gnu.gdb.arm.m-system", NULL, },
 
    /* A working register for packing/unpacking special regs, hidden from gdb */
    { ARMV7M_PMSK_BPRI_FLTMSK_CTRL, "pmsk_bpri_fltmsk_ctrl", 32, REG_TYPE_INT, NULL, NULL, NULL },
 
    /* WARNING: If you use armv7m_write_core_reg() on one of 4 following
     * special registers, the new data go to ARMV7M_PMSK_BPRI_FLTMSK_CTRL
     * cache only and are not flushed to CPU HW register.
     * To trigger write to CPU HW register, add
     *      armv7m_write_core_reg(,,ARMV7M_PMSK_BPRI_FLTMSK_CTRL,);
     */
    { ARMV7M_PRIMASK, "primask", 1, REG_TYPE_INT8, "system", "org.gnu.gdb.arm.m-system", NULL, },
    { ARMV7M_BASEPRI, "basepri", 8, REG_TYPE_INT8, "system", "org.gnu.gdb.arm.m-system", NULL, },
    { ARMV7M_FAULTMASK, "faultmask", 1, REG_TYPE_INT8, "system", "org.gnu.gdb.arm.m-system", NULL, },
    { ARMV7M_CONTROL, "control", 3, REG_TYPE_INT8, "system", "org.gnu.gdb.arm.m-system", NULL, },
 
    /* ARMv8-M security extension (TrustZone) specific registers */
    { ARMV8M_MSP_NS, "msp_ns", 32, REG_TYPE_DATA_PTR, "stack", "org.gnu.gdb.arm.secext", NULL, },
    { ARMV8M_PSP_NS, "psp_ns", 32, REG_TYPE_DATA_PTR, "stack", "org.gnu.gdb.arm.secext", NULL, },
    { ARMV8M_MSP_S, "msp_s", 32, REG_TYPE_DATA_PTR, "stack", "org.gnu.gdb.arm.secext", NULL, },
    { ARMV8M_PSP_S, "psp_s", 32, REG_TYPE_DATA_PTR, "stack", "org.gnu.gdb.arm.secext", NULL, },
    { ARMV8M_MSPLIM_S, "msplim_s", 32, REG_TYPE_DATA_PTR, "stack", "org.gnu.gdb.arm.secext", NULL, },
    { ARMV8M_PSPLIM_S, "psplim_s", 32, REG_TYPE_DATA_PTR, "stack", "org.gnu.gdb.arm.secext", NULL, },
    { ARMV8M_MSPLIM_NS, "msplim_ns", 32, REG_TYPE_DATA_PTR, "stack", "org.gnu.gdb.arm.secext", NULL, },
    { ARMV8M_PSPLIM_NS, "psplim_ns", 32, REG_TYPE_DATA_PTR, "stack", "org.gnu.gdb.arm.secext", NULL, },
 
    { ARMV8M_PMSK_BPRI_FLTMSK_CTRL_S, "pmsk_bpri_fltmsk_ctrl_s", 32, REG_TYPE_INT, NULL, NULL, NULL, },
    { ARMV8M_PRIMASK_S, "primask_s", 1, REG_TYPE_INT8, "system", "org.gnu.gdb.arm.secext", NULL, },
    { ARMV8M_BASEPRI_S, "basepri_s", 8, REG_TYPE_INT8, "system", "org.gnu.gdb.arm.secext", NULL, },
    { ARMV8M_FAULTMASK_S, "faultmask_s", 1, REG_TYPE_INT8, "system", "org.gnu.gdb.arm.secext", NULL, },
    { ARMV8M_CONTROL_S, "control_s", 3, REG_TYPE_INT8, "system", "org.gnu.gdb.arm.secext", NULL, },
 
    { ARMV8M_PMSK_BPRI_FLTMSK_CTRL_NS, "pmsk_bpri_fltmsk_ctrl_ns", 32, REG_TYPE_INT, NULL, NULL, NULL, },
    { ARMV8M_PRIMASK_NS, "primask_ns", 1, REG_TYPE_INT8, "system", "org.gnu.gdb.arm.secext", NULL, },
    { ARMV8M_BASEPRI_NS, "basepri_ns", 8, REG_TYPE_INT8, "system", "org.gnu.gdb.arm.secext", NULL, },
    { ARMV8M_FAULTMASK_NS, "faultmask_ns", 1, REG_TYPE_INT8, "system", "org.gnu.gdb.arm.secext", NULL, },
    { ARMV8M_CONTROL_NS, "control_ns", 3, REG_TYPE_INT8, "system", "org.gnu.gdb.arm.secext", NULL, },
 
    /* FPU registers */
    { ARMV7M_D0, "d0", 64, REG_TYPE_IEEE_DOUBLE, "float", "org.gnu.gdb.arm.vfp", NULL, },
    { ARMV7M_D1, "d1", 64, REG_TYPE_IEEE_DOUBLE, "float", "org.gnu.gdb.arm.vfp", NULL, },
    { ARMV7M_D2, "d2", 64, REG_TYPE_IEEE_DOUBLE, "float", "org.gnu.gdb.arm.vfp", NULL, },
    { ARMV7M_D3, "d3", 64, REG_TYPE_IEEE_DOUBLE, "float", "org.gnu.gdb.arm.vfp", NULL, },
    { ARMV7M_D4, "d4", 64, REG_TYPE_IEEE_DOUBLE, "float", "org.gnu.gdb.arm.vfp", NULL, },
    { ARMV7M_D5, "d5", 64, REG_TYPE_IEEE_DOUBLE, "float", "org.gnu.gdb.arm.vfp", NULL, },
    { ARMV7M_D6, "d6", 64, REG_TYPE_IEEE_DOUBLE, "float", "org.gnu.gdb.arm.vfp", NULL, },
    { ARMV7M_D7, "d7", 64, REG_TYPE_IEEE_DOUBLE, "float", "org.gnu.gdb.arm.vfp", NULL, },
    { ARMV7M_D8, "d8", 64, REG_TYPE_IEEE_DOUBLE, "float", "org.gnu.gdb.arm.vfp", NULL, },
    { ARMV7M_D9, "d9", 64, REG_TYPE_IEEE_DOUBLE, "float", "org.gnu.gdb.arm.vfp", NULL, },
    { ARMV7M_D10, "d10", 64, REG_TYPE_IEEE_DOUBLE, "float", "org.gnu.gdb.arm.vfp", NULL, },
    { ARMV7M_D11, "d11", 64, REG_TYPE_IEEE_DOUBLE, "float", "org.gnu.gdb.arm.vfp", NULL, },
    { ARMV7M_D12, "d12", 64, REG_TYPE_IEEE_DOUBLE, "float", "org.gnu.gdb.arm.vfp", NULL, },
    { ARMV7M_D13, "d13", 64, REG_TYPE_IEEE_DOUBLE, "float", "org.gnu.gdb.arm.vfp", NULL, },
    { ARMV7M_D14, "d14", 64, REG_TYPE_IEEE_DOUBLE, "float", "org.gnu.gdb.arm.vfp", NULL, },
    { ARMV7M_D15, "d15", 64, REG_TYPE_IEEE_DOUBLE, "float", "org.gnu.gdb.arm.vfp", NULL, },
 
    { ARMV7M_FPSCR, "fpscr", 32, REG_TYPE_INT, "float", "org.gnu.gdb.arm.vfp", NULL, },
 
    { ARMV8M_VPR, "vpr", 32, REG_TYPE_INT, "float", "org.gnu.gdb.arm.m-profile-mve", armv8m_flags_vpr, },
};
 
#define ARMV7M_NUM_REGS ARRAY_SIZE(armv7m_regs)
 
int armv7m_restore_context(struct target *target)
{
    int i;
    struct armv7m_common *armv7m = target_to_armv7m(target);
    struct reg_cache *cache = armv7m->arm.core_cache;
 
    LOG_TARGET_DEBUG(target, " ");
 
    if (armv7m->pre_restore_context)
        armv7m->pre_restore_context(target);
 
    /* The descending order of register writes is crucial for correct
     * packing of ARMV7M_PMSK_BPRI_FLTMSK_CTRL!
     * See also comments in the register table above */
    for (i = cache->num_regs - 1; i >= 0; i--) {
        struct reg *r = &cache->reg_list[i];
 
        if (r->exist && r->dirty) {
            int retval = armv7m->arm.write_core_reg(target, r, i, ARM_MODE_ANY, r->value);
            if (retval != ERROR_OK)
                return retval;
        }
    }
 
    return ERROR_OK;
}
 
/* Core state functions */
 
const 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 arm_reg *armv7m_reg = reg->arch_info;
    struct target *target = armv7m_reg->target;
    struct arm *arm = target_to_arm(target);
 
    if (target->state != TARGET_HALTED)
        return ERROR_TARGET_NOT_HALTED;
 
    retval = arm->read_core_reg(target, reg, reg->number, arm->core_mode);
 
    return retval;
}
 
static int armv7m_set_core_reg(struct reg *reg, uint8_t *buf)
{
    struct arm_reg *armv7m_reg = reg->arch_info;
    struct target *target = armv7m_reg->target;
 
    if (target->state != TARGET_HALTED)
        return ERROR_TARGET_NOT_HALTED;
 
    buf_cpy(buf, reg->value, reg->size);
    reg->dirty = true;
    reg->valid = true;
 
    return ERROR_OK;
}
 
uint32_t armv7m_map_id_to_regsel(unsigned int arm_reg_id)
{
    switch (arm_reg_id) {
    case ARMV7M_R0 ... ARMV7M_R14:
    case ARMV7M_PC:
    case ARMV7M_XPSR:
    case ARMV7M_MSP:
    case ARMV7M_PSP:
        /* NOTE:  we "know" here that the register identifiers
         * match the Cortex-M DCRSR.REGSEL selectors values
         * for R0..R14, PC, xPSR, MSP, and PSP.
         */
        return arm_reg_id;
 
    case ARMV7M_PMSK_BPRI_FLTMSK_CTRL:
        return ARMV7M_REGSEL_PMSK_BPRI_FLTMSK_CTRL;
 
    case ARMV8M_MSP_NS...ARMV8M_PSPLIM_NS:
        return arm_reg_id - ARMV8M_MSP_NS + ARMV8M_REGSEL_MSP_NS;
 
    case ARMV8M_PMSK_BPRI_FLTMSK_CTRL_S:
        return ARMV8M_REGSEL_PMSK_BPRI_FLTMSK_CTRL_S;
 
    case ARMV8M_PMSK_BPRI_FLTMSK_CTRL_NS:
        return ARMV8M_REGSEL_PMSK_BPRI_FLTMSK_CTRL_NS;
 
    case ARMV7M_FPSCR:
        return ARMV7M_REGSEL_FPSCR;
 
    case ARMV8M_VPR:
        return ARMV8M_REGSEL_VPR;
 
    case ARMV7M_D0 ... ARMV7M_D15:
        return ARMV7M_REGSEL_S0 + 2 * (arm_reg_id - ARMV7M_D0);
 
    default:
        LOG_ERROR("Bad register ID %u", arm_reg_id);
        return arm_reg_id;
    }
}
 
bool armv7m_map_reg_packing(unsigned int arm_reg_id,
                    unsigned int *reg32_id, uint32_t *offset)
{
 
    switch (arm_reg_id) {
 
    case ARMV7M_PRIMASK...ARMV7M_CONTROL:
        *reg32_id = ARMV7M_PMSK_BPRI_FLTMSK_CTRL;
        *offset = arm_reg_id - ARMV7M_PRIMASK;
        return true;
    case ARMV8M_PRIMASK_S...ARMV8M_CONTROL_S:
        *reg32_id = ARMV8M_PMSK_BPRI_FLTMSK_CTRL_S;
        *offset = arm_reg_id - ARMV8M_PRIMASK_S;
        return true;
    case ARMV8M_PRIMASK_NS...ARMV8M_CONTROL_NS:
        *reg32_id = ARMV8M_PMSK_BPRI_FLTMSK_CTRL_NS;
        *offset = arm_reg_id - ARMV8M_PRIMASK_NS;
        return true;
 
    default:
        return false;
    }
 
}
 
static int armv7m_read_core_reg(struct target *target, struct reg *r,
    int num, enum arm_mode mode)
{
    uint32_t reg_value;
    int retval;
    struct armv7m_common *armv7m = target_to_armv7m(target);
 
    assert(num < (int)armv7m->arm.core_cache->num_regs);
    assert(num == (int)r->number);
 
    /* If a code calls read_reg, it expects the cache is no more dirty.
     * Clear the dirty flag regardless of the later read succeeds or not
     * to prevent unwanted cache flush after a read error */
    r->dirty = false;
 
    if (r->size <= 8) {
        /* any 8-bit or shorter register is packed */
        uint32_t offset;
        unsigned int reg32_id;
 
        bool is_packed = armv7m_map_reg_packing(num, &reg32_id, &offset);
        if (!is_packed) {
            /* We should not get here as all 8-bit or shorter registers
             * are packed */
            assert(false);
            /* assert() does nothing if NDEBUG is defined */
            return ERROR_FAIL;
        }
        struct reg *r32 = &armv7m->arm.core_cache->reg_list[reg32_id];
 
        /* Read 32-bit container register if not cached */
        if (!r32->valid) {
            retval = armv7m_read_core_reg(target, r32, reg32_id, mode);
            if (retval != ERROR_OK)
                return retval;
        }
 
        /* Copy required bits of 32-bit container register */
        buf_cpy(r32->value + offset, r->value, r->size);
 
    } else {
        assert(r->size == 32 || r->size == 64);
 
        struct arm_reg *armv7m_core_reg = r->arch_info;
        uint32_t regsel = armv7m_map_id_to_regsel(armv7m_core_reg->num);
 
        retval = armv7m->load_core_reg_u32(target, regsel, &reg_value);
        if (retval != ERROR_OK)
            return retval;
        buf_set_u32(r->value, 0, 32, reg_value);
 
        if (r->size == 64) {
            retval = armv7m->load_core_reg_u32(target, regsel + 1, &reg_value);
            if (retval != ERROR_OK) {
                r->valid = false;
                return retval;
            }
            buf_set_u32(r->value + 4, 0, 32, reg_value);
 
            uint64_t q = buf_get_u64(r->value, 0, 64);
            LOG_TARGET_DEBUG(target, "read %s value 0x%016" PRIx64, r->name, q);
        } else {
            LOG_TARGET_DEBUG(target, "read %s value 0x%08" PRIx32, r->name, reg_value);
        }
    }
 
    r->valid = true;
 
    return ERROR_OK;
}
 
static int armv7m_write_core_reg(struct target *target, struct reg *r,
    int num, enum arm_mode mode, uint8_t *value)
{
    int retval;
    uint32_t t;
    struct armv7m_common *armv7m = target_to_armv7m(target);
 
    assert(num < (int)armv7m->arm.core_cache->num_regs);
    assert(num == (int)r->number);
 
    if (value != r->value) {
        /* If we are not flushing the cache, store the new value to the cache */
        buf_cpy(value, r->value, r->size);
    }
 
    if (r->size <= 8) {
        /* any 8-bit or shorter register is packed */
        uint32_t offset;
        unsigned int reg32_id;
 
        bool is_packed = armv7m_map_reg_packing(num, &reg32_id, &offset);
        if (!is_packed) {
            /* We should not get here as all 8-bit or shorter registers
             * are packed */
            assert(false);
            /* assert() does nothing if NDEBUG is defined */
            return ERROR_FAIL;
        }
        struct reg *r32 = &armv7m->arm.core_cache->reg_list[reg32_id];
 
        if (!r32->valid) {
            /* Before merging with other parts ensure the 32-bit register is valid */
            retval = armv7m_read_core_reg(target, r32, reg32_id, mode);
            if (retval != ERROR_OK)
                return retval;
        }
 
        /* Write a part to the 32-bit container register */
        buf_cpy(value, r32->value + offset, r->size);
        r32->dirty = true;
 
    } else {
        assert(r->size == 32 || r->size == 64);
 
        struct arm_reg *armv7m_core_reg = r->arch_info;
        uint32_t regsel = armv7m_map_id_to_regsel(armv7m_core_reg->num);
 
        t = buf_get_u32(value, 0, 32);
        retval = armv7m->store_core_reg_u32(target, regsel, t);
        if (retval != ERROR_OK)
            goto out_error;
 
        if (r->size == 64) {
            t = buf_get_u32(value + 4, 0, 32);
            retval = armv7m->store_core_reg_u32(target, regsel + 1, t);
            if (retval != ERROR_OK)
                goto out_error;
 
            uint64_t q = buf_get_u64(value, 0, 64);
            LOG_TARGET_DEBUG(target, "write %s value 0x%016" PRIx64, r->name, q);
        } else {
            LOG_TARGET_DEBUG(target, "write %s value 0x%08" PRIx32, r->name, t);
        }
    }
 
    r->valid = true;
    r->dirty = false;
 
    return ERROR_OK;
 
out_error:
    r->dirty = true;
    LOG_TARGET_ERROR(target, "Error setting register %s", r->name);
    return retval;
}
 
int armv7m_get_gdb_reg_list(struct target *target, struct reg **reg_list[],
        int *reg_list_size, enum target_register_class reg_class)
{
    struct armv7m_common *armv7m = target_to_armv7m(target);
    int i, size;
 
    if (reg_class == REG_CLASS_ALL)
        size = armv7m->arm.core_cache->num_regs;
    else
        size = ARMV7M_NUM_CORE_REGS;
 
    *reg_list = malloc(sizeof(struct reg *) * size);
    if (!*reg_list)
        return ERROR_FAIL;
 
    for (i = 0; i < size; i++)
        (*reg_list)[i] = &armv7m->arm.core_cache->reg_list[i];
 
    *reg_list_size = size;
 
    return ERROR_OK;
}
 
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,
    target_addr_t entry_point, target_addr_t exit_point,
    unsigned int timeout_ms, void *arch_info)
{
    int retval;
 
    retval = armv7m_start_algorithm(target,
            num_mem_params, mem_params,
            num_reg_params, reg_params,
            entry_point, exit_point,
            arch_info);
 
    if (retval == ERROR_OK)
        retval = armv7m_wait_algorithm(target,
                num_mem_params, mem_params,
                num_reg_params, reg_params,
                exit_point, timeout_ms,
                arch_info);
 
    return retval;
}
 
int armv7m_start_algorithm(struct target *target,
    int num_mem_params, struct mem_param *mem_params,
    int num_reg_params, struct reg_param *reg_params,
    target_addr_t entry_point, target_addr_t exit_point,
    void *arch_info)
{
    struct armv7m_common *armv7m = target_to_armv7m(target);
    struct armv7m_algorithm *armv7m_algorithm_info = arch_info;
    enum arm_mode core_mode = armv7m->arm.core_mode;
    int retval = ERROR_OK;
 
    /* 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_TARGET_ERROR(target, "current target isn't an ARMV7M target");
        return ERROR_TARGET_INVALID;
    }
 
    if (target->state != TARGET_HALTED) {
        LOG_TARGET_ERROR(target, "not halted (start target algo)");
        return ERROR_TARGET_NOT_HALTED;
    }
 
    /* Store all non-debug execution registers to armv7m_algorithm_info context */
    for (unsigned int i = 0; i < armv7m->arm.core_cache->num_regs; i++) {
        struct reg *reg = &armv7m->arm.core_cache->reg_list[i];
        if (!reg->exist)
            continue;
 
        if (!reg->valid)
            armv7m_get_core_reg(reg);
 
        if (!reg->valid)
            LOG_TARGET_WARNING(target, "Storing invalid register %s", reg->name);
 
        armv7m_algorithm_info->context[i] = buf_get_u32(reg->value, 0, 32);
    }
 
    for (int i = 0; i < num_mem_params; i++) {
        if (mem_params[i].direction == PARAM_IN)
            continue;
        retval = target_write_buffer(target, mem_params[i].address,
                mem_params[i].size,
                mem_params[i].value);
        if (retval != ERROR_OK)
            return retval;
    }
 
    for (int i = 0; i < num_reg_params; i++) {
        if (reg_params[i].direction == PARAM_IN)
            continue;
 
        struct reg *reg =
            register_get_by_name(armv7m->arm.core_cache, reg_params[i].reg_name, false);
/*      uint32_t regvalue; */
 
        if (!reg) {
            LOG_TARGET_ERROR(target, "BUG: register '%s' not found", reg_params[i].reg_name);
            return ERROR_COMMAND_SYNTAX_ERROR;
        }
 
        if (reg->size != reg_params[i].size) {
            LOG_TARGET_ERROR(target, "BUG: register '%s' size doesn't match reg_params[i].size",
                reg_params[i].reg_name);
            return ERROR_COMMAND_SYNTAX_ERROR;
        }
 
/*      regvalue = buf_get_u32(reg_params[i].value, 0, 32); */
        armv7m_set_core_reg(reg, reg_params[i].value);
    }
 
    {
        /*
         * Ensure xPSR.T is set to avoid trying to run things in arm
         * (non-thumb) mode, which armv7m does not support.
         *
         * We do this by setting the entirety of xPSR, which should
         * remove all the unknowns about xPSR state.
         *
         * Because xPSR.T is populated on reset from the vector table,
         * it might be 0 if the vector table has "bad" data in it.
         */
        struct reg *reg = &armv7m->arm.core_cache->reg_list[ARMV7M_XPSR];
        buf_set_u32(reg->value, 0, 32, 0x01000000);
        reg->valid = true;
        reg->dirty = true;
    }
 
    if (armv7m_algorithm_info->core_mode != ARM_MODE_ANY &&
            armv7m_algorithm_info->core_mode != core_mode) {
 
        /* we cannot set ARM_MODE_HANDLER, so use ARM_MODE_THREAD instead */
        if (armv7m_algorithm_info->core_mode == ARM_MODE_HANDLER) {
            armv7m_algorithm_info->core_mode = ARM_MODE_THREAD;
            LOG_TARGET_INFO(target, "ARM_MODE_HANDLER not currently supported, using ARM_MODE_THREAD instead");
        }
 
        LOG_TARGET_DEBUG(target, "setting core_mode: 0x%2.2x",
            armv7m_algorithm_info->core_mode);
        buf_set_u32(armv7m->arm.core_cache->reg_list[ARMV7M_CONTROL].value,
            0, 1, armv7m_algorithm_info->core_mode);
        armv7m->arm.core_cache->reg_list[ARMV7M_CONTROL].dirty = true;
        armv7m->arm.core_cache->reg_list[ARMV7M_CONTROL].valid = true;
    }
 
    /* save previous core mode */
    armv7m_algorithm_info->core_mode = core_mode;
 
    retval = target_resume(target, false, entry_point, true, true);
 
    return retval;
}
 
int armv7m_wait_algorithm(struct target *target,
    int num_mem_params, struct mem_param *mem_params,
    int num_reg_params, struct reg_param *reg_params,
    target_addr_t exit_point, unsigned int timeout_ms,
    void *arch_info)
{
    struct armv7m_common *armv7m = target_to_armv7m(target);
    struct armv7m_algorithm *armv7m_algorithm_info = arch_info;
    int retval = ERROR_OK;
 
    /* 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_TARGET_ERROR(target, "current target isn't an ARMV7M target");
        return ERROR_TARGET_INVALID;
    }
 
    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) {
        retval = target_halt(target);
        if (retval != ERROR_OK)
            return retval;
        retval = target_wait_state(target, TARGET_HALTED, 500);
        if (retval != ERROR_OK)
            return retval;
        return ERROR_TARGET_TIMEOUT;
    }
 
    if (exit_point) {
        /* PC value has been cached in cortex_m_debug_entry() */
        uint32_t pc = buf_get_u32(armv7m->arm.pc->value, 0, 32);
        if (pc != exit_point) {
            LOG_TARGET_DEBUG(target, "failed algorithm halted at 0x%" PRIx32 ", expected 0x%" TARGET_PRIxADDR,
                      pc, exit_point);
            return ERROR_TARGET_ALGO_EXIT;
        }
    }
 
    /* Read memory values to mem_params[] */
    for (int i = 0; i < num_mem_params; i++) {
        if (mem_params[i].direction != PARAM_OUT) {
            retval = target_read_buffer(target, mem_params[i].address,
                    mem_params[i].size,
                    mem_params[i].value);
            if (retval != 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->arm.core_cache,
                    reg_params[i].reg_name,
                    false);
 
            if (!reg) {
                LOG_TARGET_ERROR(target, "BUG: register '%s' not found",
                    reg_params[i].reg_name);
                return ERROR_COMMAND_SYNTAX_ERROR;
            }
 
            if (reg->size != reg_params[i].size) {
                LOG_TARGET_ERROR(target,
                    "BUG: register '%s' size doesn't match reg_params[i].size",
                    reg_params[i].reg_name);
                return ERROR_COMMAND_SYNTAX_ERROR;
            }
 
            buf_set_u32(reg_params[i].value, 0, 32, buf_get_u32(reg->value, 0, 32));
        }
    }
 
    for (int i = armv7m->arm.core_cache->num_regs - 1; i >= 0; i--) {
        struct reg *reg = &armv7m->arm.core_cache->reg_list[i];
        if (!reg->exist)
            continue;
 
        uint32_t regvalue;
        regvalue = buf_get_u32(reg->value, 0, 32);
        if (regvalue != armv7m_algorithm_info->context[i]) {
            LOG_TARGET_DEBUG(target, "restoring register %s with value 0x%8.8" PRIx32,
                      reg->name, armv7m_algorithm_info->context[i]);
            buf_set_u32(reg->value,
                0, 32, armv7m_algorithm_info->context[i]);
            reg->valid = true;
            reg->dirty = true;
        }
    }
 
    /* restore previous core mode */
    if (armv7m_algorithm_info->core_mode != armv7m->arm.core_mode) {
        LOG_TARGET_DEBUG(target, "restoring core_mode: 0x%2.2x", armv7m_algorithm_info->core_mode);
        buf_set_u32(armv7m->arm.core_cache->reg_list[ARMV7M_CONTROL].value,
            0, 1, armv7m_algorithm_info->core_mode);
        armv7m->arm.core_cache->reg_list[ARMV7M_CONTROL].dirty = true;
        armv7m->arm.core_cache->reg_list[ARMV7M_CONTROL].valid = true;
    }
 
    armv7m->arm.core_mode = armv7m_algorithm_info->core_mode;
 
    return retval;
}
 
int armv7m_arch_state(struct target *target)
{
    struct armv7m_common *armv7m = target_to_armv7m(target);
    struct arm *arm = &armv7m->arm;
    uint32_t ctrl, sp;
 
    /* avoid filling log waiting for fileio reply */
    if (target->semihosting && target->semihosting->hit_fileio)
        return ERROR_OK;
 
    ctrl = buf_get_u32(arm->core_cache->reg_list[ARMV7M_CONTROL].value, 0, 32);
    sp = buf_get_u32(arm->core_cache->reg_list[ARMV7M_R13].value, 0, 32);
 
    LOG_TARGET_USER(target, "halted due to %s, current mode: %s %s\n"
        "xPSR: %#8.8" PRIx32 " pc: %#8.8" PRIx32 " %csp: %#8.8" PRIx32 "%s%s",
        debug_reason_name(target),
        arm_mode_name(arm->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,
        (target->semihosting && target->semihosting->is_active) ? ", semihosting" : "",
        (target->semihosting && target->semihosting->is_fileio) ? " fileio" : "");
 
    return ERROR_OK;
}
 
static const struct reg_arch_type armv7m_reg_type = {
    .get = armv7m_get_core_reg,
    .set = armv7m_set_core_reg,
};
 
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 arm_reg *arch_info = calloc(num_regs, sizeof(struct arm_reg));
    struct reg_feature *feature;
    int i;
 
    /* 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;
 
    for (i = 0; i < num_regs; i++) {
        arch_info[i].num = armv7m_regs[i].id;
        arch_info[i].target = target;
        arch_info[i].arm = arm;
 
        reg_list[i].name = armv7m_regs[i].name;
        reg_list[i].size = armv7m_regs[i].bits;
        reg_list[i].value = arch_info[i].value;
        reg_list[i].dirty = false;
        reg_list[i].valid = false;
        reg_list[i].hidden = (i == ARMV7M_PMSK_BPRI_FLTMSK_CTRL ||
                i == ARMV8M_PMSK_BPRI_FLTMSK_CTRL_NS || i == ARMV8M_PMSK_BPRI_FLTMSK_CTRL_S);
        reg_list[i].type = &armv7m_reg_type;
        reg_list[i].arch_info = &arch_info[i];
 
        reg_list[i].group = armv7m_regs[i].group;
        reg_list[i].number = i;
        reg_list[i].exist = true;
        reg_list[i].caller_save = true; /* gdb defaults to true */
 
        if (reg_list[i].hidden)
            continue;
 
        feature = calloc(1, sizeof(struct reg_feature));
        if (feature) {
            feature->name = armv7m_regs[i].feature;
            reg_list[i].feature = feature;
        } else
            LOG_TARGET_ERROR(target, "unable to allocate feature list");
 
        reg_list[i].reg_data_type = calloc(1, sizeof(struct reg_data_type));
        if (reg_list[i].reg_data_type) {
            if (armv7m_regs[i].data_type)
                *reg_list[i].reg_data_type = *armv7m_regs[i].data_type;
            else
                reg_list[i].reg_data_type->type = armv7m_regs[i].type;
        } else {
            LOG_TARGET_ERROR(target, "unable to allocate reg type list");
        }
    }
 
    arm->cpsr = reg_list + ARMV7M_XPSR;
    arm->pc = reg_list + ARMV7M_PC;
    arm->core_cache = cache;
 
    return cache;
}
 
void armv7m_free_reg_cache(struct target *target)
{
    struct armv7m_common *armv7m = target_to_armv7m(target);
    struct arm *arm = &armv7m->arm;
    struct reg_cache *cache;
    struct reg *reg;
    unsigned int i;
 
    cache = arm->core_cache;
 
    if (!cache)
        return;
 
    for (i = 0; i < cache->num_regs; i++) {
        reg = &cache->reg_list[i];
 
        free(reg->feature);
        free(reg->reg_data_type);
    }
 
    free(cache->reg_list[0].arch_info);
    free(cache->reg_list);
    free(cache);
 
    arm->core_cache = NULL;
}
 
static int armv7m_setup_semihosting(struct target *target, int enable)
{
    /* nothing todo for armv7m */
    return ERROR_OK;
}
 
int armv7m_init_arch_info(struct target *target, struct armv7m_common *armv7m)
{
    struct arm *arm = &armv7m->arm;
 
    armv7m->common_magic = ARMV7M_COMMON_MAGIC;
    armv7m->fp_feature = FP_NONE;
    armv7m->trace_config.trace_bus_id = 1;
    /* Enable stimulus port #0 by default */
    armv7m->trace_config.itm_ter[0] = 1;
 
    arm->core_state = ARM_STATE_THUMB;
    arm->core_type = ARM_CORE_TYPE_M_PROFILE;
    arm->arch_info = armv7m;
    arm->setup_semihosting = armv7m_setup_semihosting;
 
    arm->read_core_reg = armv7m_read_core_reg;
    arm->write_core_reg = armv7m_write_core_reg;
 
    return arm_init_arch_info(target, arm);
}
 
int armv7m_checksum_memory(struct target *target,
    target_addr_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 uint8_t cortex_m_crc_code[] = {
#include "../../contrib/loaders/checksum/armv7m_crc.inc"
    };
 
    retval = target_alloc_working_area(target, sizeof(cortex_m_crc_code), &crc_algorithm);
    if (retval != ERROR_OK)
        return retval;
 
    retval = target_write_buffer(target, crc_algorithm->address,
            sizeof(cortex_m_crc_code), (uint8_t *)cortex_m_crc_code);
    if (retval != ERROR_OK)
        goto cleanup;
 
    armv7m_info.common_magic = ARMV7M_COMMON_MAGIC;
    armv7m_info.core_mode = ARM_MODE_THREAD;
 
    init_reg_param(&reg_params[0], "r0", 32, PARAM_IN_OUT);
    init_reg_param(&reg_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);
 
    unsigned int timeout = 20000 * (1 + (count / (1024 * 1024)));
 
    retval = target_run_algorithm(target, 0, NULL, 2, reg_params, crc_algorithm->address,
            crc_algorithm->address + (sizeof(cortex_m_crc_code) - 6),
            timeout, &armv7m_info);
 
    if (retval == ERROR_OK)
        *checksum = buf_get_u32(reg_params[0].value, 0, 32);
    else
        LOG_TARGET_ERROR(target, "error executing cortex_m crc algorithm");
 
    destroy_reg_param(&reg_params[0]);
    destroy_reg_param(&reg_params[1]);
 
cleanup:
    target_free_working_area(target, crc_algorithm);
 
    return retval;
}
 
int armv7m_blank_check_memory(struct target *target,
    struct target_memory_check_block *blocks, int num_blocks, uint8_t erased_value)
{
    struct working_area *erase_check_algorithm;
    struct working_area *erase_check_params;
    struct reg_param reg_params[2];
    struct armv7m_algorithm armv7m_info;
    int retval;
 
    static bool timed_out;
 
    static const uint8_t erase_check_code[] = {
#include "../../contrib/loaders/erase_check/armv7m_erase_check.inc"
    };
 
    const uint32_t code_size = sizeof(erase_check_code);
 
    /* make sure we have a working area */
    if (target_alloc_working_area(target, code_size,
        &erase_check_algorithm) != ERROR_OK)
        return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
 
    retval = target_write_buffer(target, erase_check_algorithm->address,
            code_size, erase_check_code);
    if (retval != ERROR_OK)
        goto cleanup1;
 
    /* prepare blocks array for algo */
    struct algo_block {
        union {
            uint32_t size;
            uint32_t result;
        };
        uint32_t address;
    };
 
    uint32_t avail = target_get_working_area_avail(target);
    int blocks_to_check = avail / sizeof(struct algo_block) - 1;
    if (num_blocks < blocks_to_check)
        blocks_to_check = num_blocks;
 
    struct algo_block *params = malloc((blocks_to_check+1)*sizeof(struct algo_block));
    if (!params) {
        retval = ERROR_FAIL;
        goto cleanup1;
    }
 
    int i;
    uint32_t total_size = 0;
    for (i = 0; i < blocks_to_check; i++) {
        total_size += blocks[i].size;
        target_buffer_set_u32(target, (uint8_t *)&(params[i].size),
                        blocks[i].size / sizeof(uint32_t));
        target_buffer_set_u32(target, (uint8_t *)&(params[i].address),
                        blocks[i].address);
    }
    target_buffer_set_u32(target, (uint8_t *)&(params[blocks_to_check].size), 0);
 
    uint32_t param_size = (blocks_to_check + 1) * sizeof(struct algo_block);
    if (target_alloc_working_area(target, param_size,
            &erase_check_params) != ERROR_OK) {
        retval = ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
        goto cleanup2;
    }
 
    retval = target_write_buffer(target, erase_check_params->address,
                param_size, (uint8_t *)params);
    if (retval != ERROR_OK)
        goto cleanup3;
 
    uint32_t erased_word = erased_value | (erased_value << 8)
                   | (erased_value << 16) | (erased_value << 24);
 
    LOG_TARGET_DEBUG(target, "Starting erase check of %d blocks, parameters@"
         TARGET_ADDR_FMT, blocks_to_check, erase_check_params->address);
 
    armv7m_info.common_magic = ARMV7M_COMMON_MAGIC;
    armv7m_info.core_mode = ARM_MODE_THREAD;
 
    init_reg_param(&reg_params[0], "r0", 32, PARAM_OUT);
    buf_set_u32(reg_params[0].value, 0, 32, erase_check_params->address);
 
    init_reg_param(&reg_params[1], "r1", 32, PARAM_OUT);
    buf_set_u32(reg_params[1].value, 0, 32, erased_word);
 
    /* assume CPU clk at least 1 MHz */
    unsigned int timeout = (timed_out ? 30000 : 2000) + total_size * 3 / 1000;
 
    retval = target_run_algorithm(target,
                0, NULL,
                ARRAY_SIZE(reg_params), reg_params,
                erase_check_algorithm->address,
                erase_check_algorithm->address + (code_size - 2),
                timeout,
                &armv7m_info);
 
    timed_out = retval == ERROR_TARGET_TIMEOUT;
    if (retval != ERROR_OK && !timed_out)
        goto cleanup4;
 
    retval = target_read_buffer(target, erase_check_params->address,
                param_size, (uint8_t *)params);
    if (retval != ERROR_OK)
        goto cleanup4;
 
    for (i = 0; i < blocks_to_check; i++) {
        uint32_t result = target_buffer_get_u32(target,
                    (uint8_t *)&(params[i].result));
        if (result != 0 && result != 1)
            break;
 
        blocks[i].result = result;
    }
    if (i && timed_out)
        LOG_TARGET_INFO(target, "Slow CPU clock: %d blocks checked, %d remain. Continuing...",
            i, num_blocks - i);
 
    retval = i;     /* return number of blocks really checked */
 
cleanup4:
    destroy_reg_param(&reg_params[0]);
    destroy_reg_param(&reg_params[1]);
 
cleanup3:
    target_free_working_area(target, erase_check_params);
cleanup2:
    free(params);
cleanup1:
    target_free_working_area(target, erase_check_algorithm);
 
    return retval;
}
 
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_TARGET_DEBUG(target, "Skipping over BKPT instruction");
            }
        }
    }
 
    if (inst_found)
        *inst_found = result;
 
    return ERROR_OK;
}
 
const struct command_registration armv7m_command_handlers[] = {
    {
        .name = "arm",
        .mode = COMMAND_ANY,
        .help = "ARM command group",
        .usage = "",
        .chain = arm_all_profiles_command_handlers,
    },
    COMMAND_REGISTRATION_DONE
};