ambiqmicro.c

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// SPDX-License-Identifier: BSD-3-Clause
 
/******************************************************************************
 *
 * @file ambiqmicro.c
 *
 * @brief Ambiq Micro flash driver.
 *
 *****************************************************************************/
 
/******************************************************************************
 * Copyright (c) 2015, David Racine <dracine at ambiqmicro.com>
 *
 * Copyright (c) 2016, Rick Foos <rfoos at solengtech.com>
 *
 * Copyright (c) 2015-2016, Ambiq Micro, Inc.
 *
 * All rights reserved.
 *****************************************************************************/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
 
#include "jtag/interface.h"
#include "imp.h"
#include "target/algorithm.h"
#include "target/armv7m.h"
#include "target/cortex_m.h"
 
#define CHECK_STATUS(rc, msg) { \
        if (rc != ERROR_OK) { \
            LOG_ERROR("status(%d):%s\n", rc, msg); } }
 
/*
 * Address and Key defines.
 */
#define PROGRAM_KEY      (0x12344321)
#define OTP_PROGRAM_KEY  (0x87655678)
 
#define FLASH_PROGRAM_MAIN_FROM_SRAM                0x0800005d
#define FLASH_PROGRAM_OTP_FROM_SRAM                 0x08000061
#define FLASH_ERASE_LIST_MAIN_PAGES_FROM_SRAM       0x08000065
#define FLASH_MASS_ERASE_MAIN_PAGES_FROM_SRAM       0x08000069
 
 
static const uint32_t apollo_flash_size[] = {
    1 << 15,
    1 << 16,
    1 << 17,
    1 << 18,
    1 << 19,
    1 << 20,
    1 << 21
};
 
static const uint32_t apollo_sram_size[] = {
    1 << 15,
    1 << 16,
    1 << 17,
    1 << 18,
    1 << 19,
    1 << 20,
    1 << 21
};
 
struct ambiqmicro_flash_bank {
    /* chip id register */
 
    bool probed;
 
    const char *target_name;
    uint8_t target_class;
 
    uint32_t sramsiz;
    uint32_t flshsiz;
 
    /* flash geometry */
    uint32_t num_pages;
    uint32_t pagesize;
    uint32_t pages_in_lockregion;
 
    /* nv memory bits */
    uint16_t num_lockbits;
 
    /* main clock status */
    uint32_t rcc;
    uint32_t rcc2;
    uint8_t mck_valid;
    uint8_t xtal_mask;
    uint32_t iosc_freq;
    uint32_t mck_freq;
    const char *iosc_desc;
    const char *mck_desc;
};
 
static struct {
    uint8_t class;
    uint8_t partno;
    const char *partname;
} ambiqmicro_parts[6] = {
    {0xFF, 0x00, "Unknown"},
    {0x01, 0x00, "Apollo"},
    {0x02, 0x00, "Apollo2"},
    {0x03, 0x00, "Unknown"},
    {0x04, 0x00, "Unknown"},
    {0x05, 0x00, "Apollo"},
};
 
static char *ambiqmicro_classname[6] = {
    "Unknown", "Apollo", "Apollo2", "Unknown", "Unknown", "Apollo"
};
 
/***************************************************************************
*   openocd command interface                                              *
***************************************************************************/
 
/* flash_bank ambiqmicro <base> <size> 0 0 <target#>
 */
FLASH_BANK_COMMAND_HANDLER(ambiqmicro_flash_bank_command)
{
    struct ambiqmicro_flash_bank *ambiqmicro_info;
 
    if (CMD_ARGC < 6)
        return ERROR_COMMAND_SYNTAX_ERROR;
 
    ambiqmicro_info = calloc(1, sizeof(struct ambiqmicro_flash_bank));
 
    bank->driver_priv = ambiqmicro_info;
 
    ambiqmicro_info->target_name = "Unknown target";
 
    /* part wasn't probed yet */
    ambiqmicro_info->probed = false;
 
    return ERROR_OK;
}
 
static int get_ambiqmicro_info(struct flash_bank *bank, struct command_invocation *cmd)
{
    struct ambiqmicro_flash_bank *ambiqmicro_info = bank->driver_priv;
    char *classname;
 
    if (!ambiqmicro_info->probed) {
        LOG_ERROR("Target not probed");
        return ERROR_FLASH_BANK_NOT_PROBED;
    }
 
    /* Check class name in range. */
    if (ambiqmicro_info->target_class < sizeof(ambiqmicro_classname))
        classname = ambiqmicro_classname[ambiqmicro_info->target_class];
    else
        classname = ambiqmicro_classname[0];
 
    command_print_sameline(cmd, "\nAmbiq Micro information: Chip is "
        "class %d (%s) %s\n",
        ambiqmicro_info->target_class,
        classname,
        ambiqmicro_info->target_name);
 
    return ERROR_OK;
}
 
/***************************************************************************
*   chip identification and status                                         *
***************************************************************************/
 
/* Fill in driver info structure */
static int ambiqmicro_read_part_info(struct flash_bank *bank)
{
    struct ambiqmicro_flash_bank *ambiqmicro_info = bank->driver_priv;
    struct target *target = bank->target;
    uint32_t part_num = 0;
    int retval;
 
    /*
     * Read Part Number.
     */
    retval = target_read_u32(target, 0x40020000, &part_num);
    if (retval != ERROR_OK) {
        LOG_ERROR("status(0x%x):Could not read part_num.\n", retval);
        /* Set part_num to default device */
        part_num = 0;
    }
    LOG_DEBUG("Part number: 0x%" PRIx32, part_num);
 
    /*
     * Determine device class.
     */
    ambiqmicro_info->target_class = (part_num & 0xFF000000) >> 24;
 
    switch (ambiqmicro_info->target_class) {
        case 1:     /* 1 - Apollo */
        case 5:     /* 5 - Apollo Bootloader */
            bank->base = bank->bank_number * 0x40000;
            ambiqmicro_info->pagesize = 2048;
            ambiqmicro_info->flshsiz =
            apollo_flash_size[(part_num & 0x00F00000) >> 20];
            ambiqmicro_info->sramsiz =
            apollo_sram_size[(part_num & 0x000F0000) >> 16];
            ambiqmicro_info->num_pages = ambiqmicro_info->flshsiz /
            ambiqmicro_info->pagesize;
            if (ambiqmicro_info->num_pages > 128) {
                ambiqmicro_info->num_pages = 128;
                ambiqmicro_info->flshsiz = 1024 * 256;
            }
            break;
 
        default:
            LOG_INFO("Unknown Class. Using Apollo-64 as default.");
 
            bank->base = bank->bank_number * 0x40000;
            ambiqmicro_info->pagesize = 2048;
            ambiqmicro_info->flshsiz = apollo_flash_size[1];
            ambiqmicro_info->sramsiz = apollo_sram_size[0];
            ambiqmicro_info->num_pages = ambiqmicro_info->flshsiz /
            ambiqmicro_info->pagesize;
            if (ambiqmicro_info->num_pages > 128) {
                ambiqmicro_info->num_pages = 128;
                ambiqmicro_info->flshsiz = 1024 * 256;
            }
            break;
 
    }
 
    if (ambiqmicro_info->target_class < ARRAY_SIZE(ambiqmicro_parts))
        ambiqmicro_info->target_name =
            ambiqmicro_parts[ambiqmicro_info->target_class].partname;
    else
        ambiqmicro_info->target_name =
            ambiqmicro_parts[0].partname;
 
    LOG_DEBUG("num_pages: %" PRIu32 ", pagesize: %" PRIu32 ", flash: %" PRIu32 ", sram: %" PRIu32,
        ambiqmicro_info->num_pages,
        ambiqmicro_info->pagesize,
        ambiqmicro_info->flshsiz,
        ambiqmicro_info->sramsiz);
 
    return ERROR_OK;
}
 
/***************************************************************************
*   flash operations                                                       *
***************************************************************************/
 
static int ambiqmicro_protect_check(struct flash_bank *bank)
{
    struct ambiqmicro_flash_bank *ambiqmicro = bank->driver_priv;
    int status = ERROR_OK;
    uint32_t i;
 
 
    if (!ambiqmicro->probed) {
        LOG_ERROR("Target not probed");
        return ERROR_FLASH_BANK_NOT_PROBED;
    }
 
    for (i = 0; i < (unsigned) bank->num_sectors; i++)
        bank->sectors[i].is_protected = -1;
 
    return status;
}
static int check_flash_status(struct target *target, uint32_t address)
{
    uint32_t retflash;
    int rc;
    rc = target_read_u32(target, address, &retflash);
    /* target connection failed. */
    if (rc != ERROR_OK) {
        LOG_DEBUG("%s:%d:%s(): status(0x%x)\n",
            __FILE__, __LINE__, __func__, rc);
        return rc;
    }
    /* target flash failed, unknown cause. */
    if (retflash != 0) {
        LOG_ERROR("Flash not happy: status(0x%" PRIx32 ")", retflash);
        return ERROR_FLASH_OPERATION_FAILED;
    }
    return ERROR_OK;
}
 
static int ambiqmicro_exec_command(struct target *target,
    uint32_t command,
    uint32_t flash_return_address)
{
    int retval, retflash;
 
    retval = target_resume(
        target,
        false,
        command,
        true,
        true);
 
    CHECK_STATUS(retval, "error executing ambiqmicro command");
 
    /*
     * Wait for halt.
     */
    for (;; ) {
        target_poll(target);
        if (target->state == TARGET_HALTED)
            break;
        else if (target->state == TARGET_RUNNING ||
            target->state == TARGET_DEBUG_RUNNING) {
            /*
             * Keep polling until target halts.
             */
            target_poll(target);
            alive_sleep(100);
            LOG_DEBUG("state = %d", target->state);
        } else {
            LOG_ERROR("Target not halted or running %d", target->state);
            break;
        }
    }
 
    /*
     * Read return value, flash error takes precedence.
     */
    retflash = check_flash_status(target, flash_return_address);
    if (retflash != ERROR_OK)
        retval = retflash;
 
    /* Return code from target_resume OR flash. */
    return retval;
}
 
static int ambiqmicro_mass_erase(struct flash_bank *bank)
{
    struct target *target = NULL;
    struct ambiqmicro_flash_bank *ambiqmicro_info = NULL;
    int retval = ERROR_OK;
 
    ambiqmicro_info = bank->driver_priv;
    target = bank->target;
 
    if (target->state != TARGET_HALTED) {
        LOG_ERROR("Target not halted");
        return ERROR_TARGET_NOT_HALTED;
    }
 
    if (!ambiqmicro_info->probed) {
        LOG_ERROR("Target not probed");
        return ERROR_FLASH_BANK_NOT_PROBED;
    }
 
    /*
     * Clear Bootloader bit.
     */
    retval = target_write_u32(target, 0x400201a0, 0x0);
    CHECK_STATUS(retval, "error clearing bootloader bit.");
 
    /*
     * Set up the SRAM.
     */
 
    /*
     * Bank.
     */
    retval = target_write_u32(target, 0x10000000, bank->bank_number);
    CHECK_STATUS(retval, "error writing target SRAM parameters.");
 
    /*
     * Write Key.
     */
    retval = target_write_u32(target, 0x10000004, PROGRAM_KEY);
    CHECK_STATUS(retval, "error writing target SRAM parameters.");
 
    /*
     * Breakpoint.
     */
    retval = target_write_u32(target, 0x10000008, 0xfffffffe);
    CHECK_STATUS(retval, "error writing target SRAM parameters.");
 
    /*
     * Erase the main array.
     */
    LOG_INFO("Mass erase on bank %d.", bank->bank_number);
 
    /*
     * passed pc, addr = ROM function, handle breakpoints, not debugging.
     */
    retval = ambiqmicro_exec_command(target, FLASH_MASS_ERASE_MAIN_PAGES_FROM_SRAM, 0x10000008);
    CHECK_STATUS(retval, "error executing ambiqmicro flash mass erase.");
    if (retval != ERROR_OK)
        return retval;
 
    /*
     * Set Bootloader bit, regardless of command execution.
     */
    retval = target_write_u32(target, 0x400201a0, 0x1);
    CHECK_STATUS(retval, "error setting bootloader bit.");
 
    return retval;
}
 
 
static int ambiqmicro_erase(struct flash_bank *bank, unsigned int first,
        unsigned int last)
{
    struct ambiqmicro_flash_bank *ambiqmicro_info = bank->driver_priv;
    struct target *target = bank->target;
    int retval;
 
    if (bank->target->state != TARGET_HALTED) {
        LOG_ERROR("Target not halted");
        return ERROR_TARGET_NOT_HALTED;
    }
 
    if (!ambiqmicro_info->probed) {
        LOG_ERROR("Target not probed");
        return ERROR_FLASH_BANK_NOT_PROBED;
    }
 
    /*
     * Check pages.
     * Fix num_pages for the device.
     */
    if ((last < first) || (last >= ambiqmicro_info->num_pages))
        return ERROR_FLASH_SECTOR_INVALID;
 
    /*
     * Just Mass Erase if all pages are given.
     * TODO: Fix num_pages for the device
     */
    if ((first == 0) && (last == (ambiqmicro_info->num_pages - 1)))
        return ambiqmicro_mass_erase(bank);
 
    /*
     * Clear Bootloader bit.
     */
    retval = target_write_u32(target, 0x400201a0, 0x0);
    CHECK_STATUS(retval, "error clearing bootloader bit.");
 
    /*
     * Set up the SRAM.
     */
 
    /*
     * Bank.
     */
    retval = target_write_u32(target, 0x10000000, bank->bank_number);
    CHECK_STATUS(retval, "error writing target SRAM parameters.");
 
    /*
     * Number of pages to erase.
     */
    retval = target_write_u32(target, 0x10000004, 1 + (last-first));
    CHECK_STATUS(retval, "error writing target SRAM parameters.");
 
    /*
     * Write Key.
     */
    retval = target_write_u32(target, 0x10000008, PROGRAM_KEY);
    CHECK_STATUS(retval, "error writing target SRAM parameters.");
 
    /*
     * Breakpoint.
     */
    retval = target_write_u32(target, 0x1000000c, 0xfffffffe);
    CHECK_STATUS(retval, "error writing target SRAM parameters.");
 
    /*
     * Pointer to flash address.
     */
    retval = target_write_u32(target, 0x10000010, first);
    CHECK_STATUS(retval, "error writing target SRAM parameters.");
    if (retval != ERROR_OK)
        return retval;
 
    /*
     * Erase the pages.
     */
    LOG_INFO("Erasing pages %u to %u on bank %u", first, last, bank->bank_number);
 
    /*
     * passed pc, addr = ROM function, handle breakpoints, not debugging.
     */
    retval = ambiqmicro_exec_command(target, FLASH_ERASE_LIST_MAIN_PAGES_FROM_SRAM, 0x1000000C);
    CHECK_STATUS(retval, "error executing flash page erase");
    if (retval != ERROR_OK)
        return retval;
 
    LOG_INFO("%u pages erased!", 1+(last-first));
 
    if (first == 0) {
        /*
         * Set Bootloader bit.
         */
        retval = target_write_u32(target, 0x400201a0, 0x1);
        CHECK_STATUS(retval, "error setting bootloader bit.");
        if (retval != ERROR_OK)
            return retval;
    }
 
    return retval;
}
 
static int ambiqmicro_protect(struct flash_bank *bank, int set,
        unsigned int first, unsigned int last)
{
    /* struct ambiqmicro_flash_bank *ambiqmicro_info = bank->driver_priv;
     * struct target *target = bank->target; */
 
    /*
     * TODO
     */
    LOG_INFO("Not yet implemented");
 
    if (bank->target->state != TARGET_HALTED) {
        LOG_ERROR("Target not halted");
        return ERROR_TARGET_NOT_HALTED;
    }
 
    return ERROR_OK;
}
 
static int ambiqmicro_write_block(struct flash_bank *bank,
    const uint8_t *buffer, uint32_t offset, uint32_t count)
{
    /* struct ambiqmicro_flash_bank *ambiqmicro_info = bank->driver_priv; */
    struct target *target = bank->target;
    uint32_t address = bank->base + offset;
    uint32_t buffer_pointer = 0x10000010;
    uint32_t maxbuffer;
    uint32_t thisrun_count;
    int retval = ERROR_OK;
 
    if (((count%4) != 0) || ((offset%4) != 0)) {
        LOG_ERROR("write block must be multiple of 4 bytes in offset & length");
        return ERROR_FAIL;
    }
 
    /*
     * Max buffer size for this device.
     * Hard code 6kB for the buffer.
     */
    maxbuffer = 0x1800;
 
    LOG_INFO("Flashing main array");
 
    while (count > 0) {
        if (count > maxbuffer)
            thisrun_count = maxbuffer;
        else
            thisrun_count = count;
 
        /*
         * Set up the SRAM.
         */
 
        /*
         * Pointer to flash.
         */
        retval = target_write_u32(target, 0x10000000, address);
        CHECK_STATUS(retval, "error writing target SRAM parameters.");
 
        /*
         * Number of 32-bit words to program.
         */
        retval = target_write_u32(target, 0x10000004, thisrun_count/4);
        CHECK_STATUS(retval, "error writing target SRAM parameters.");
 
        /*
         * Write Key.
         */
        retval = target_write_u32(target, 0x10000008, PROGRAM_KEY);
        CHECK_STATUS(retval, "error writing target SRAM parameters.");
 
        /*
         * Breakpoint.
         */
        retval = target_write_u32(target, 0x1000000c, 0xfffffffe);
        CHECK_STATUS(retval, "error writing target SRAM parameters.");
 
        /*
         * Write Buffer.
         */
        retval = target_write_buffer(target, buffer_pointer, thisrun_count, buffer);
 
        if (retval != ERROR_OK) {
            CHECK_STATUS(retval, "error writing target SRAM parameters.");
            break;
        }
 
        LOG_DEBUG("address = 0x%08" PRIx32, address);
 
        retval = ambiqmicro_exec_command(target, FLASH_PROGRAM_MAIN_FROM_SRAM, 0x1000000c);
        CHECK_STATUS(retval, "error executing ambiqmicro flash write algorithm");
        if (retval != ERROR_OK)
            break;
        buffer += thisrun_count;
        address += thisrun_count;
        count -= thisrun_count;
    }
 
 
    LOG_INFO("Main array flashed");
 
    /*
     * Clear Bootloader bit.
     */
    retval = target_write_u32(target, 0x400201a0, 0x0);
    CHECK_STATUS(retval, "error clearing bootloader bit");
 
    return retval;
}
 
static int ambiqmicro_write(struct flash_bank *bank, const uint8_t *buffer,
    uint32_t offset, uint32_t count)
{
    int retval;
 
    /* try using a block write */
    retval = ambiqmicro_write_block(bank, buffer, offset, count);
    if (retval != ERROR_OK)
        LOG_ERROR("write failed");
 
    return retval;
}
 
static int ambiqmicro_probe(struct flash_bank *bank)
{
    struct ambiqmicro_flash_bank *ambiqmicro_info = bank->driver_priv;
    int retval;
 
    /* If this is a ambiqmicro chip, it has flash; probe() is just
     * to figure out how much is present.  Only do it once.
     */
    if (ambiqmicro_info->probed) {
        LOG_INFO("Target already probed");
        return ERROR_OK;
    }
 
    /* ambiqmicro_read_part_info() already handled error checking and
     * reporting.  Note that it doesn't write, so we don't care about
     * whether the target is halted or not.
     */
    retval = ambiqmicro_read_part_info(bank);
    if (retval != ERROR_OK)
        return retval;
 
    free(bank->sectors);
 
    /* provide this for the benefit of the NOR flash framework */
    bank->size = ambiqmicro_info->pagesize * ambiqmicro_info->num_pages;
    bank->num_sectors = ambiqmicro_info->num_pages;
    bank->sectors = malloc(sizeof(struct flash_sector) * bank->num_sectors);
    for (unsigned int i = 0; i < bank->num_sectors; i++) {
        bank->sectors[i].offset = i * ambiqmicro_info->pagesize;
        bank->sectors[i].size = ambiqmicro_info->pagesize;
        bank->sectors[i].is_erased = -1;
        bank->sectors[i].is_protected = -1;
    }
 
    /*
     * Part has been probed.
     */
    ambiqmicro_info->probed = true;
 
    return retval;
}
 
static int ambiqmicro_otp_program(struct flash_bank *bank,
    uint32_t offset, uint32_t count)
{
    struct target *target = NULL;
    struct ambiqmicro_flash_bank *ambiqmicro_info = NULL;
    int retval;
 
    ambiqmicro_info = bank->driver_priv;
    target = bank->target;
 
    if (target->state != TARGET_HALTED) {
        LOG_ERROR("Target not halted");
        return ERROR_TARGET_NOT_HALTED;
    }
 
    if (!ambiqmicro_info->probed) {
        LOG_ERROR("Target not probed");
        return ERROR_FLASH_BANK_NOT_PROBED;
    }
 
    if (count > 256) {
        LOG_ERROR("Count must be < 256");
        return ERROR_FLASH_DST_BREAKS_ALIGNMENT;
    }
 
    /*
     * Clear Bootloader bit.
     */
    retval = target_write_u32(target, 0x400201a0, 0x0);
    CHECK_STATUS(retval, "error clearing bootloader bit.");
 
    /*
     * Set up the SRAM.
     */
 
    /*
     * Bank.
     */
    retval = target_write_u32(target, 0x10000000, offset);
    CHECK_STATUS(retval, "error setting target SRAM parameters.");
 
    /*
     * Num of words to program.
     */
    retval = target_write_u32(target, 0x10000004, count);
    CHECK_STATUS(retval, "error setting target SRAM parameters.");
 
    /*
     * Write Key.
     */
    retval = target_write_u32(target, 0x10000008, OTP_PROGRAM_KEY);
    CHECK_STATUS(retval, "error setting target SRAM parameters.");
 
    /*
     * Breakpoint.
     */
    retval = target_write_u32(target, 0x1000000c, 0xfffffffe);
    CHECK_STATUS(retval, "error setting target SRAM parameters.");
    if (retval != ERROR_OK)
        return retval;
 
    /*
     * Program OTP.
     */
    LOG_INFO("Programming OTP offset 0x%08" PRIx32, offset);
 
    /*
     * passed pc, addr = ROM function, handle breakpoints, not debugging.
     */
    retval = ambiqmicro_exec_command(target, FLASH_PROGRAM_OTP_FROM_SRAM, 0x1000000C);
    CHECK_STATUS(retval, "error executing ambiqmicro otp program algorithm");
 
    LOG_INFO("Programming OTP finished.");
 
    return retval;
}
 
 
 
COMMAND_HANDLER(ambiqmicro_handle_mass_erase_command)
{
    if (CMD_ARGC < 1)
        return ERROR_COMMAND_SYNTAX_ERROR;
 
    struct flash_bank *bank;
    int retval = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &bank);
    if (retval != ERROR_OK)
        return retval;
 
    if (ambiqmicro_mass_erase(bank) == ERROR_OK)
        command_print(CMD, "ambiqmicro mass erase complete");
    else
        command_print(CMD, "ambiqmicro mass erase failed");
 
    return ERROR_OK;
}
 
COMMAND_HANDLER(ambiqmicro_handle_page_erase_command)
{
    struct flash_bank *bank;
    uint32_t first, last;
    int retval;
 
    if (CMD_ARGC < 3)
        return ERROR_COMMAND_SYNTAX_ERROR;
 
    COMMAND_PARSE_NUMBER(u32, CMD_ARGV[1], first);
    COMMAND_PARSE_NUMBER(u32, CMD_ARGV[2], last);
 
    retval = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &bank);
    if (retval != ERROR_OK)
        return retval;
 
    if (ambiqmicro_erase(bank, first, last) == ERROR_OK)
        command_print(CMD, "ambiqmicro page erase complete");
    else
        command_print(CMD, "ambiqmicro page erase failed");
 
    return ERROR_OK;
}
 
 
COMMAND_HANDLER(ambiqmicro_handle_program_otp_command)
{
    struct flash_bank *bank;
    uint32_t offset, count;
    int retval;
 
    if (CMD_ARGC < 3)
        return ERROR_COMMAND_SYNTAX_ERROR;
 
    COMMAND_PARSE_NUMBER(u32, CMD_ARGV[1], offset);
    COMMAND_PARSE_NUMBER(u32, CMD_ARGV[2], count);
 
    command_print(CMD, "offset=0x%08" PRIx32 " count=%" PRIu32, offset, count);
 
    CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &bank);
 
    retval = ambiqmicro_otp_program(bank, offset, count);
 
    if (retval != ERROR_OK)
        LOG_ERROR("error check log");
 
    return ERROR_OK;
}
 
 
 
static const struct command_registration ambiqmicro_exec_command_handlers[] = {
    {
        .name = "mass_erase",
        .usage = "<bank>",
        .handler = ambiqmicro_handle_mass_erase_command,
        .mode = COMMAND_EXEC,
        .help = "Erase entire device",
    },
    {
        .name = "page_erase",
        .usage = "<bank> <first> <last>",
        .handler = ambiqmicro_handle_page_erase_command,
        .mode = COMMAND_EXEC,
        .help = "Erase device pages",
    },
    {
        .name = "program_otp",
        .handler = ambiqmicro_handle_program_otp_command,
        .mode = COMMAND_EXEC,
        .usage = "<bank> <offset> <count>",
        .help =
            "Program OTP (assumes you have already written array starting at 0x10000010)",
    },
    COMMAND_REGISTRATION_DONE
};
static const struct command_registration ambiqmicro_command_handlers[] = {
    {
        .name = "ambiqmicro",
        .mode = COMMAND_EXEC,
        .help = "ambiqmicro flash command group",
        .usage = "Support for Ambiq Micro parts.",
        .chain = ambiqmicro_exec_command_handlers,
    },
    COMMAND_REGISTRATION_DONE
};
 
const struct flash_driver ambiqmicro_flash = {
    .name = "ambiqmicro",
    .commands = ambiqmicro_command_handlers,
    .flash_bank_command = ambiqmicro_flash_bank_command,
    .erase = ambiqmicro_erase,
    .protect = ambiqmicro_protect,
    .write = ambiqmicro_write,
    .read = default_flash_read,
    .probe = ambiqmicro_probe,
    .auto_probe = ambiqmicro_probe,
    .erase_check = default_flash_blank_check,
    .protect_check = ambiqmicro_protect_check,
    .info = get_ambiqmicro_info,
    .free_driver_priv = default_flash_free_driver_priv,
};