arm720t.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) 2009 by Øyvind Harboe                                   *
 *   oyvind.harboe@zylin.com                                               *
 ***************************************************************************/
 
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
 
#include "arm720t.h"
#include <helper/time_support.h>
#include <helper/string_choices.h>
#include "target_type.h"
#include "register.h"
#include "arm_opcodes.h"
 
 
/*
 * ARM720 is an ARM7TDMI-S with MMU and ETM7.  For information, see
 * ARM DDI 0229C especially Chapter 9 about debug support.
 */
 
#if 0
#define _DEBUG_INSTRUCTION_EXECUTION_
#endif
 
static int arm720t_scan_cp15(struct target *target,
        uint32_t out, uint32_t *in, int instruction, int clock_arg)
{
    int retval;
    struct arm720t_common *arm720t = target_to_arm720(target);
    struct arm_jtag *jtag_info;
    struct scan_field fields[2];
    uint8_t out_buf[4];
    uint8_t instruction_buf = instruction;
 
    jtag_info = &arm720t->arm7_9_common.jtag_info;
 
    buf_set_u32(out_buf, 0, 32, flip_u32(out, 32));
 
    retval = arm_jtag_scann(jtag_info, 0xf, TAP_DRPAUSE);
    if (retval != ERROR_OK)
        return retval;
    retval = arm_jtag_set_instr(jtag_info->tap, jtag_info->intest_instr, NULL, TAP_DRPAUSE);
    if (retval != ERROR_OK)
        return retval;
 
    fields[0].num_bits = 1;
    fields[0].out_value = &instruction_buf;
    fields[0].in_value = NULL;
 
    fields[1].num_bits = 32;
    fields[1].out_value = out_buf;
    fields[1].in_value = NULL;
 
    if (in) {
        fields[1].in_value = (uint8_t *)in;
        jtag_add_dr_scan(jtag_info->tap, 2, fields, TAP_DRPAUSE);
        jtag_add_callback(arm7flip32, (jtag_callback_data_t)in);
    } else
        jtag_add_dr_scan(jtag_info->tap, 2, fields, TAP_DRPAUSE);
 
    if (clock_arg)
        jtag_add_runtest(0, TAP_DRPAUSE);
 
#ifdef _DEBUG_INSTRUCTION_EXECUTION_
    retval = jtag_execute_queue();
    if (retval != ERROR_OK)
        return retval;
 
    if (in)
        LOG_DEBUG("out: %8.8x, in: %8.8x, instruction: %i, clock: %i", out, *in, instruction, clock);
    else
        LOG_DEBUG("out: %8.8x, instruction: %i, clock: %i", out, instruction, clock_arg);
#else
        LOG_DEBUG("out: %8.8" PRIx32 ", instruction: %i, clock: %i", out, instruction, clock_arg);
#endif
 
    return ERROR_OK;
}
 
static int arm720t_read_cp15(struct target *target, uint32_t opcode, uint32_t *value)
{
    /* fetch CP15 opcode */
    arm720t_scan_cp15(target, opcode, NULL, 1, 1);
    /* "DECODE" stage */
    arm720t_scan_cp15(target, ARMV4_5_NOP, NULL, 1, 1);
    /* "EXECUTE" stage (1) */
    arm720t_scan_cp15(target, ARMV4_5_NOP, NULL, 1, 0);
    arm720t_scan_cp15(target, 0x0, NULL, 0, 1);
    /* "EXECUTE" stage (2) */
    arm720t_scan_cp15(target, 0x0, NULL, 0, 1);
    /* "EXECUTE" stage (3), CDATA is read */
    arm720t_scan_cp15(target, ARMV4_5_NOP, value, 1, 1);
 
    return ERROR_OK;
}
 
static int arm720t_write_cp15(struct target *target, uint32_t opcode, uint32_t value)
{
    /* fetch CP15 opcode */
    arm720t_scan_cp15(target, opcode, NULL, 1, 1);
    /* "DECODE" stage */
    arm720t_scan_cp15(target, ARMV4_5_NOP, NULL, 1, 1);
    /* "EXECUTE" stage (1) */
    arm720t_scan_cp15(target, ARMV4_5_NOP, NULL, 1, 0);
    arm720t_scan_cp15(target, 0x0, NULL, 0, 1);
    /* "EXECUTE" stage (2) */
    arm720t_scan_cp15(target, value, NULL, 0, 1);
    arm720t_scan_cp15(target, ARMV4_5_NOP, NULL, 1, 1);
 
    return ERROR_OK;
}
 
static int arm720t_get_ttb(struct target *target, uint32_t *result)
{
    uint32_t ttb = 0x0;
 
    int retval;
 
    retval = arm720t_read_cp15(target, 0xee120f10, &ttb);
    if (retval != ERROR_OK)
        return retval;
    retval = jtag_execute_queue();
    if (retval != ERROR_OK)
        return retval;
 
    ttb &= 0xffffc000;
 
    *result = ttb;
 
    return ERROR_OK;
}
 
static int arm720t_disable_mmu_caches(struct target *target,
        int mmu, int d_u_cache, int i_cache)
{
    uint32_t cp15_control;
    int retval;
 
    /* read cp15 control register */
    retval = arm720t_read_cp15(target, 0xee110f10, &cp15_control);
    if (retval != ERROR_OK)
        return retval;
    retval = jtag_execute_queue();
    if (retval != ERROR_OK)
        return retval;
 
    if (mmu)
        cp15_control &= ~0x1U;
 
    if (d_u_cache || i_cache)
        cp15_control &= ~0x4U;
 
    retval = arm720t_write_cp15(target, 0xee010f10, cp15_control);
    return retval;
}
 
static int arm720t_enable_mmu_caches(struct target *target,
        int mmu, int d_u_cache, int i_cache)
{
    uint32_t cp15_control;
    int retval;
 
    /* read cp15 control register */
    retval = arm720t_read_cp15(target, 0xee110f10, &cp15_control);
    if (retval != ERROR_OK)
        return retval;
    retval = jtag_execute_queue();
    if (retval != ERROR_OK)
        return retval;
 
    if (mmu)
        cp15_control |= 0x1U;
 
    if (d_u_cache || i_cache)
        cp15_control |= 0x4U;
 
    retval = arm720t_write_cp15(target, 0xee010f10, cp15_control);
    return retval;
}
 
static int arm720t_post_debug_entry(struct target *target)
{
    struct arm720t_common *arm720t = target_to_arm720(target);
    int retval;
 
    /* examine cp15 control reg */
    retval = arm720t_read_cp15(target, 0xee110f10, &arm720t->cp15_control_reg);
    if (retval != ERROR_OK)
        return retval;
    retval = jtag_execute_queue();
    if (retval != ERROR_OK)
        return retval;
    LOG_DEBUG("cp15_control_reg: %8.8" PRIx32 "", arm720t->cp15_control_reg);
 
    arm720t->armv4_5_mmu.mmu_enabled = arm720t->cp15_control_reg & 0x1U;
    arm720t->armv4_5_mmu.armv4_5_cache.d_u_cache_enabled =
        arm720t->cp15_control_reg & 0x4U;
    arm720t->armv4_5_mmu.armv4_5_cache.i_cache_enabled = false;
 
    /* save i/d fault status and address register */
    retval = arm720t_read_cp15(target, 0xee150f10, &arm720t->fsr_reg);
    if (retval != ERROR_OK)
        return retval;
    retval = arm720t_read_cp15(target, 0xee160f10, &arm720t->far_reg);
    if (retval != ERROR_OK)
        return retval;
    retval = jtag_execute_queue();
    return retval;
}
 
static void arm720t_pre_restore_context(struct target *target)
{
    struct arm720t_common *arm720t = target_to_arm720(target);
 
    /* restore i/d fault status and address register */
    arm720t_write_cp15(target, 0xee050f10, arm720t->fsr_reg);
    arm720t_write_cp15(target, 0xee060f10, arm720t->far_reg);
}
 
static int arm720t_arch_state(struct target *target)
{
    struct arm720t_common *arm720t = target_to_arm720(target);
 
    arm_arch_state(target);
    LOG_USER("MMU: %s, Cache: %s",
             str_enabled_disabled(arm720t->armv4_5_mmu.mmu_enabled),
             str_enabled_disabled(arm720t->armv4_5_mmu.armv4_5_cache.d_u_cache_enabled));
 
    return ERROR_OK;
}
 
static int arm720_mmu(struct target *target, bool *enabled)
{
    if (target->state != TARGET_HALTED) {
        LOG_TARGET_ERROR(target, "not halted");
        return ERROR_TARGET_NOT_HALTED;
    }
 
    *enabled = target_to_arm720(target)->armv4_5_mmu.mmu_enabled;
    return ERROR_OK;
}
 
static int arm720_virt2phys(struct target *target,
        target_addr_t virtual, target_addr_t *physical)
{
    uint32_t cb;
    struct arm720t_common *arm720t = target_to_arm720(target);
 
    uint32_t ret;
    int retval = armv4_5_mmu_translate_va(target,
            &arm720t->armv4_5_mmu, virtual, &cb, &ret);
    if (retval != ERROR_OK)
        return retval;
    *physical = ret;
    return ERROR_OK;
}
 
static int arm720t_read_memory(struct target *target,
        target_addr_t address, uint32_t size, uint32_t count, uint8_t *buffer)
{
    int retval;
    struct arm720t_common *arm720t = target_to_arm720(target);
 
    /* disable cache, but leave MMU enabled */
    if (arm720t->armv4_5_mmu.armv4_5_cache.d_u_cache_enabled) {
        retval = arm720t_disable_mmu_caches(target, 0, 1, 0);
        if (retval != ERROR_OK)
            return retval;
    }
    retval = arm7_9_read_memory(target, address, size, count, buffer);
 
    if (arm720t->armv4_5_mmu.armv4_5_cache.d_u_cache_enabled) {
        retval = arm720t_enable_mmu_caches(target, 0, 1, 0);
        if (retval != ERROR_OK)
            return retval;
    }
 
    return retval;
}
 
static int arm720t_read_phys_memory(struct target *target,
        target_addr_t address, uint32_t size, uint32_t count, uint8_t *buffer)
{
    struct arm720t_common *arm720t = target_to_arm720(target);
 
    return armv4_5_mmu_read_physical(target, &arm720t->armv4_5_mmu, address, size, count, buffer);
}
 
static int arm720t_write_phys_memory(struct target *target,
        target_addr_t address, uint32_t size, uint32_t count, const uint8_t *buffer)
{
    struct arm720t_common *arm720t = target_to_arm720(target);
 
    return armv4_5_mmu_write_physical(target, &arm720t->armv4_5_mmu, address, size, count, buffer);
}
 
static int arm720t_soft_reset_halt(struct target *target)
{
    int retval = ERROR_OK;
    struct arm720t_common *arm720t = target_to_arm720(target);
    struct reg *dbg_stat = &arm720t->arm7_9_common
            .eice_cache->reg_list[EICE_DBG_STAT];
    struct arm *arm = &arm720t->arm7_9_common.arm;
 
    retval = target_halt(target);
    if (retval != ERROR_OK)
        return retval;
 
    int64_t then = timeval_ms();
    int timeout;
    while (!(timeout = ((timeval_ms()-then) > 1000))) {
        if (buf_get_u32(dbg_stat->value, EICE_DBG_STATUS_DBGACK, 1) == 0) {
            embeddedice_read_reg(dbg_stat);
            retval = jtag_execute_queue();
            if (retval != ERROR_OK)
                return retval;
        } else
            break;
        if (debug_level >= 3)
            alive_sleep(100);
        else
            keep_alive();
    }
    if (timeout) {
        LOG_ERROR("Failed to halt CPU after 1 sec");
        return ERROR_TARGET_TIMEOUT;
    }
 
    target->state = TARGET_HALTED;
 
    /* SVC, ARM state, IRQ and FIQ disabled */
    uint32_t cpsr;
 
    cpsr = buf_get_u32(arm->cpsr->value, 0, 32);
    cpsr &= ~0xff;
    cpsr |= 0xd3;
    arm_set_cpsr(arm, cpsr);
    arm->cpsr->dirty = true;
 
    /* start fetching from 0x0 */
    buf_set_u32(arm->pc->value, 0, 32, 0x0);
    arm->pc->dirty = true;
    arm->pc->valid = true;
 
    retval = arm720t_disable_mmu_caches(target, 1, 1, 1);
    if (retval != ERROR_OK)
        return retval;
    arm720t->armv4_5_mmu.mmu_enabled = false;
    arm720t->armv4_5_mmu.armv4_5_cache.d_u_cache_enabled = false;
    arm720t->armv4_5_mmu.armv4_5_cache.i_cache_enabled = false;
 
    retval = target_call_event_callbacks(target, TARGET_EVENT_HALTED);
    if (retval != ERROR_OK)
        return retval;
 
    return ERROR_OK;
}
 
static int arm720t_init_target(struct command_context *cmd_ctx, struct target *target)
{
    return arm7tdmi_init_target(cmd_ctx, target);
}
 
static void arm720t_deinit_target(struct target *target)
{
    arm7tdmi_deinit_target(target);
}
 
/* FIXME remove forward decls */
static int arm720t_mrc(struct target *target, int cpnum,
        uint32_t op1, uint32_t op2,
        uint32_t crn, uint32_t crm,
        uint32_t *value);
static int arm720t_mcr(struct target *target, int cpnum,
        uint32_t op1, uint32_t op2,
        uint32_t crn, uint32_t crm,
        uint32_t value);
 
static int arm720t_init_arch_info(struct target *target,
        struct arm720t_common *arm720t, struct jtag_tap *tap)
{
    struct arm7_9_common *arm7_9 = &arm720t->arm7_9_common;
 
    arm7_9->arm.mrc = arm720t_mrc;
    arm7_9->arm.mcr = arm720t_mcr;
 
    arm7tdmi_init_arch_info(target, arm7_9, tap);
 
    arm720t->common_magic = ARM720T_COMMON_MAGIC;
 
    arm7_9->post_debug_entry = arm720t_post_debug_entry;
    arm7_9->pre_restore_context = arm720t_pre_restore_context;
 
    arm720t->armv4_5_mmu.armv4_5_cache.ctype = -1;
    arm720t->armv4_5_mmu.get_ttb = arm720t_get_ttb;
    arm720t->armv4_5_mmu.read_memory = arm7_9_read_memory;
    arm720t->armv4_5_mmu.write_memory = arm7_9_write_memory;
    arm720t->armv4_5_mmu.disable_mmu_caches = arm720t_disable_mmu_caches;
    arm720t->armv4_5_mmu.enable_mmu_caches = arm720t_enable_mmu_caches;
    arm720t->armv4_5_mmu.has_tiny_pages = 0;
    arm720t->armv4_5_mmu.mmu_enabled = false;
 
    return ERROR_OK;
}
 
static int arm720t_target_create(struct target *target)
{
    struct arm720t_common *arm720t = calloc(1, sizeof(*arm720t));
 
    arm720t->arm7_9_common.arm.arch = ARM_ARCH_V4;
    return arm720t_init_arch_info(target, arm720t, target->tap);
}
 
static int arm720t_mrc(struct target *target, int cpnum,
        uint32_t op1, uint32_t op2,
        uint32_t crn, uint32_t crm,
        uint32_t *value)
{
    if (cpnum != 15) {
        LOG_ERROR("Only cp15 is supported");
        return ERROR_FAIL;
    }
 
    /* read "to" r0 */
    return arm720t_read_cp15(target,
            ARMV4_5_MRC(cpnum, op1, 0, crn, crm, op2),
            value);
 
}
 
static int arm720t_mcr(struct target *target, int cpnum,
        uint32_t op1, uint32_t op2,
        uint32_t crn, uint32_t crm,
        uint32_t value)
{
    if (cpnum != 15) {
        LOG_ERROR("Only cp15 is supported");
        return ERROR_FAIL;
    }
 
    /* write "from" r0 */
    return arm720t_write_cp15(target,
            ARMV4_5_MCR(cpnum, op1, 0, crn, crm, op2),
            value);
}
 
static const struct command_registration arm720t_command_handlers[] = {
    {
        .chain = arm7_9_command_handlers,
    },
    COMMAND_REGISTRATION_DONE
};
 
struct target_type arm720t_target = {
    .name = "arm720t",
 
    .poll = arm7_9_poll,
    .arch_state = arm720t_arch_state,
 
    .halt = arm7_9_halt,
    .resume = arm7_9_resume,
    .step = arm7_9_step,
 
    .assert_reset = arm7_9_assert_reset,
    .deassert_reset = arm7_9_deassert_reset,
    .soft_reset_halt = arm720t_soft_reset_halt,
 
    .get_gdb_arch = arm_get_gdb_arch,
    .get_gdb_reg_list = arm_get_gdb_reg_list,
 
    .read_memory = arm720t_read_memory,
    .write_memory = arm7_9_write_memory_opt,
    .read_phys_memory = arm720t_read_phys_memory,
    .write_phys_memory = arm720t_write_phys_memory,
    .mmu = arm720_mmu,
    .virt2phys = arm720_virt2phys,
 
    .checksum_memory = arm_checksum_memory,
    .blank_check_memory = arm_blank_check_memory,
 
    .run_algorithm = armv4_5_run_algorithm,
 
    .add_breakpoint = arm7_9_add_breakpoint,
    .remove_breakpoint = arm7_9_remove_breakpoint,
    .add_watchpoint = arm7_9_add_watchpoint,
    .remove_watchpoint = arm7_9_remove_watchpoint,
 
    .commands = arm720t_command_handlers,
    .target_create = arm720t_target_create,
    .init_target = arm720t_init_target,
    .deinit_target = arm720t_deinit_target,
    .examine = arm7_9_examine,
    .check_reset = arm7_9_check_reset,
};