flash/nor/nrf5: drop useless for cycle condition

[openocd.git] / src / flash / nor / nrf5.c

// SPDX-License-Identifier: GPL-2.0-or-later

/***************************************************************************
 *   Copyright (C) 2013 Synapse Product Development                        *
 *   Andrey Smirnov <andrew.smironv@gmail.com>                             *
 *   Angus Gratton <gus@projectgus.com>                                    *
 *   Erdem U. Altunyurt <spamjunkeater@gmail.com>                          *
 ***************************************************************************/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "imp.h"
#include <helper/binarybuffer.h>
#include <target/algorithm.h>
#include <target/armv7m.h>
#include <helper/types.h>
#include <helper/time_support.h>
#include <helper/bits.h>

/* Both those values are constant across the current spectrum ofr nRF5 devices */
#define WATCHDOG_REFRESH_REGISTER       0x40010600
#define WATCHDOG_REFRESH_VALUE          0x6e524635

enum {
        NRF5_FLASH_BASE = 0x00000000,
};

enum nrf5_ficr_registers {
        NRF5_FICR_BASE = 0x10000000, /* Factory Information Configuration Registers */

#define NRF5_FICR_REG(offset) (NRF5_FICR_BASE + offset)

        NRF5_FICR_CODEPAGESIZE          = NRF5_FICR_REG(0x010),
        NRF5_FICR_CODESIZE              = NRF5_FICR_REG(0x014),

        NRF51_FICR_CLENR0               = NRF5_FICR_REG(0x028),
        NRF51_FICR_PPFC                 = NRF5_FICR_REG(0x02C),
        NRF51_FICR_NUMRAMBLOCK          = NRF5_FICR_REG(0x034),
        NRF51_FICR_SIZERAMBLOCK0        = NRF5_FICR_REG(0x038),
        NRF51_FICR_SIZERAMBLOCK1        = NRF5_FICR_REG(0x03C),
        NRF51_FICR_SIZERAMBLOCK2        = NRF5_FICR_REG(0x040),
        NRF51_FICR_SIZERAMBLOCK3        = NRF5_FICR_REG(0x044),

        /* CONFIGID is documented on nRF51 series only.
         * On nRF52 is present but not documented */
        NRF5_FICR_CONFIGID              = NRF5_FICR_REG(0x05C),

        /* Following registers are available on nRF52 and on nRF51 since rev 3 */
        NRF5_FICR_INFO_PART                     = NRF5_FICR_REG(0x100),
        NRF5_FICR_INFO_VARIANT          = NRF5_FICR_REG(0x104),
        NRF5_FICR_INFO_PACKAGE          = NRF5_FICR_REG(0x108),
        NRF5_FICR_INFO_RAM                      = NRF5_FICR_REG(0x10C),
        NRF5_FICR_INFO_FLASH            = NRF5_FICR_REG(0x110),
};

enum nrf5_uicr_registers {
        NRF5_UICR_BASE = 0x10001000, /* User Information
                                       * Configuration Registers */

#define NRF5_UICR_REG(offset) (NRF5_UICR_BASE + offset)

        NRF51_UICR_CLENR0       = NRF5_UICR_REG(0x000),
};

enum nrf5_nvmc_registers {
        NRF5_NVMC_BASE = 0x4001E000, /* Non-Volatile Memory
                                       * Controller Registers */

#define NRF5_NVMC_REG(offset) (NRF5_NVMC_BASE + offset)

        NRF5_NVMC_READY = NRF5_NVMC_REG(0x400),
        NRF5_NVMC_CONFIG        = NRF5_NVMC_REG(0x504),
        NRF5_NVMC_ERASEPAGE     = NRF5_NVMC_REG(0x508),
        NRF5_NVMC_ERASEALL      = NRF5_NVMC_REG(0x50C),
        NRF5_NVMC_ERASEUICR     = NRF5_NVMC_REG(0x514),

        NRF5_BPROT_BASE = 0x40000000,
};

enum nrf5_nvmc_config_bits {
        NRF5_NVMC_CONFIG_REN = 0x00,
        NRF5_NVMC_CONFIG_WEN = 0x01,
        NRF5_NVMC_CONFIG_EEN = 0x02,

};

struct nrf52_ficr_info {
        uint32_t part;
        uint32_t variant;
        uint32_t package;
        uint32_t ram;
        uint32_t flash;
};

enum nrf5_features {
        NRF5_FEATURE_SERIES_51  = BIT(0),
        NRF5_FEATURE_SERIES_52  = BIT(1),
        NRF5_FEATURE_BPROT              = BIT(2),
        NRF5_FEATURE_ACL_PROT   = BIT(3),
};

struct nrf5_device_spec {
        uint16_t hwid;
        const char *part;
        const char *variant;
        const char *build_code;
        unsigned int flash_size_kb;
        enum nrf5_features features;
};

struct nrf5_info {
        unsigned int refcount;

        struct nrf5_bank {
                struct nrf5_info *chip;
                bool probed;
        } bank[2];
        struct target *target;

        /* chip identification stored in nrf5_probe() for use in nrf5_info() */
        bool ficr_info_valid;
        struct nrf52_ficr_info ficr_info;
        const struct nrf5_device_spec *spec;
        uint16_t hwid;
        enum nrf5_features features;
        unsigned int flash_size_kb;
        unsigned int ram_size_kb;
};

#define NRF51_DEVICE_DEF(id, pt, var, bcode, fsize) \
{                                                   \
.hwid          = (id),                              \
.part          = pt,                                \
.variant       = var,                               \
.build_code    = bcode,                             \
.flash_size_kb = (fsize),                           \
.features      = NRF5_FEATURE_SERIES_51,            \
}

/*
 * The table maps known HWIDs to the part numbers, variant
 * build code and some other info. For nRF51 rev 1 and 2 devices
 * this is the only way how to get the part number and variant.
 *
 * All tested nRF51 rev 3 devices have FICR INFO fields
 * but the fields are not documented in RM so we keep HWIDs in
 * this table.
 *
 * nRF52 and newer devices have FICR INFO documented, the autodetection
 * can rely on it and HWIDs table is not used.
 *
 * The known devices table below is derived from the "nRF5x series
 * compatibility matrix" documents.
 *
 * Up to date with Matrix v2.0, plus some additional HWIDs.
 *
 * The additional HWIDs apply where the build code in the matrix is
 * shown as Gx0, Bx0, etc. In these cases the HWID in the matrix is
 * for x==0, x!=0 means different (unspecified) HWIDs.
 */
static const struct nrf5_device_spec nrf5_known_devices_table[] = {
        /* nRF51822 Devices (IC rev 1). */
        NRF51_DEVICE_DEF(0x001D, "51822", "QFAA", "CA/C0", 256),
        NRF51_DEVICE_DEF(0x0026, "51822", "QFAB", "AA",    128),
        NRF51_DEVICE_DEF(0x0027, "51822", "QFAB", "A0",    128),
        NRF51_DEVICE_DEF(0x0020, "51822", "CEAA", "BA",    256),
        NRF51_DEVICE_DEF(0x002F, "51822", "CEAA", "B0",    256),

        /* Some early nRF51-DK (PCA10028) & nRF51-Dongle (PCA10031) boards
           with built-in jlink seem to use engineering samples not listed
           in the nRF51 Series Compatibility Matrix V1.0. */
        NRF51_DEVICE_DEF(0x0071, "51822", "QFAC", "AB",    256),

        /* nRF51822 Devices (IC rev 2). */
        NRF51_DEVICE_DEF(0x002A, "51822", "QFAA", "FA0",   256),
        NRF51_DEVICE_DEF(0x0044, "51822", "QFAA", "GC0",   256),
        NRF51_DEVICE_DEF(0x003C, "51822", "QFAA", "G0",    256),
        NRF51_DEVICE_DEF(0x0057, "51822", "QFAA", "G2",    256),
        NRF51_DEVICE_DEF(0x0058, "51822", "QFAA", "G3",    256),
        NRF51_DEVICE_DEF(0x004C, "51822", "QFAB", "B0",    128),
        NRF51_DEVICE_DEF(0x0040, "51822", "CEAA", "CA0",   256),
        NRF51_DEVICE_DEF(0x0047, "51822", "CEAA", "DA0",   256),
        NRF51_DEVICE_DEF(0x004D, "51822", "CEAA", "D00",   256),

        /* nRF51822 Devices (IC rev 3). */
        NRF51_DEVICE_DEF(0x0072, "51822", "QFAA", "H0",    256),
        NRF51_DEVICE_DEF(0x00D1, "51822", "QFAA", "H2",    256),
        NRF51_DEVICE_DEF(0x007B, "51822", "QFAB", "C0",    128),
        NRF51_DEVICE_DEF(0x0083, "51822", "QFAC", "A0",    256),
        NRF51_DEVICE_DEF(0x0084, "51822", "QFAC", "A1",    256),
        NRF51_DEVICE_DEF(0x007D, "51822", "CDAB", "A0",    128),
        NRF51_DEVICE_DEF(0x0079, "51822", "CEAA", "E0",    256),
        NRF51_DEVICE_DEF(0x0087, "51822", "CFAC", "A0",    256),
        NRF51_DEVICE_DEF(0x008F, "51822", "QFAA", "H1",    256),

        /* nRF51422 Devices (IC rev 1). */
        NRF51_DEVICE_DEF(0x001E, "51422", "QFAA", "CA",    256),
        NRF51_DEVICE_DEF(0x0024, "51422", "QFAA", "C0",    256),
        NRF51_DEVICE_DEF(0x0031, "51422", "CEAA", "A0A",   256),

        /* nRF51422 Devices (IC rev 2). */
        NRF51_DEVICE_DEF(0x002D, "51422", "QFAA", "DAA",   256),
        NRF51_DEVICE_DEF(0x002E, "51422", "QFAA", "E0",    256),
        NRF51_DEVICE_DEF(0x0061, "51422", "QFAB", "A00",   128),
        NRF51_DEVICE_DEF(0x0050, "51422", "CEAA", "B0",    256),

        /* nRF51422 Devices (IC rev 3). */
        NRF51_DEVICE_DEF(0x0073, "51422", "QFAA", "F0",    256),
        NRF51_DEVICE_DEF(0x007C, "51422", "QFAB", "B0",    128),
        NRF51_DEVICE_DEF(0x0085, "51422", "QFAC", "A0",    256),
        NRF51_DEVICE_DEF(0x0086, "51422", "QFAC", "A1",    256),
        NRF51_DEVICE_DEF(0x007E, "51422", "CDAB", "A0",    128),
        NRF51_DEVICE_DEF(0x007A, "51422", "CEAA", "C0",    256),
        NRF51_DEVICE_DEF(0x0088, "51422", "CFAC", "A0",    256),

        /* The driver fully autodetects nRF52 series devices by FICR INFO,
         * no need for nRF52xxx HWIDs in this table */
};

struct nrf5_device_package {
        uint32_t package;
        const char *code;
};

/* Newer devices have FICR INFO.PACKAGE.
 * This table converts its value to two character code */
static const struct nrf5_device_package nrf52_packages_table[] = {
        { 0x2000, "QF" },
        { 0x2001, "CH" },
        { 0x2002, "CI" },
        { 0x2003, "QC" },
        { 0x2004, "QI/CA" },    /* differs nRF52805, 810, 811: CA, nRF52833, 840: QI */
        { 0x2005, "CK" },
        { 0x2007, "QD" },
        { 0x2008, "CJ" },
        { 0x2009, "CF" },
};

const struct flash_driver nrf5_flash, nrf51_flash;

static bool nrf5_bank_is_probed(const struct flash_bank *bank)
{
        struct nrf5_bank *nbank = bank->driver_priv;
        assert(nbank);

        return nbank->probed;
}

static int nrf5_wait_for_nvmc(struct nrf5_info *chip)
{
        uint32_t ready;
        int res;
        int timeout_ms = 340;
        int64_t ts_start = timeval_ms();

        do {
                res = target_read_u32(chip->target, NRF5_NVMC_READY, &ready);
                if (res != ERROR_OK) {
                        LOG_ERROR("Error waiting NVMC_READY: generic flash write/erase error (check protection etc...)");
                        return res;
                }

                if (ready == 0x00000001)
                        return ERROR_OK;

                keep_alive();

        } while ((timeval_ms()-ts_start) < timeout_ms);

        LOG_DEBUG("Timed out waiting for NVMC_READY");
        return ERROR_FLASH_BUSY;
}

static int nrf5_nvmc_erase_enable(struct nrf5_info *chip)
{
        int res;
        res = target_write_u32(chip->target,
                               NRF5_NVMC_CONFIG,
                               NRF5_NVMC_CONFIG_EEN);

        if (res != ERROR_OK) {
                LOG_ERROR("Failed to enable erase operation");
                return res;
        }

        /*
          According to NVMC examples in Nordic SDK busy status must be
          checked after writing to NVMC_CONFIG
         */
        res = nrf5_wait_for_nvmc(chip);
        if (res != ERROR_OK)
                LOG_ERROR("Erase enable did not complete");

        return res;
}

static int nrf5_nvmc_write_enable(struct nrf5_info *chip)
{
        int res;
        res = target_write_u32(chip->target,
                               NRF5_NVMC_CONFIG,
                               NRF5_NVMC_CONFIG_WEN);

        if (res != ERROR_OK) {
                LOG_ERROR("Failed to enable write operation");
                return res;
        }

        /*
          According to NVMC examples in Nordic SDK busy status must be
          checked after writing to NVMC_CONFIG
         */
        res = nrf5_wait_for_nvmc(chip);
        if (res != ERROR_OK)
                LOG_ERROR("Write enable did not complete");

        return res;
}

static int nrf5_nvmc_read_only(struct nrf5_info *chip)
{
        int res;
        res = target_write_u32(chip->target,
                               NRF5_NVMC_CONFIG,
                               NRF5_NVMC_CONFIG_REN);

        if (res != ERROR_OK) {
                LOG_ERROR("Failed to enable read-only operation");
                return res;
        }
        /*
          According to NVMC examples in Nordic SDK busy status must be
          checked after writing to NVMC_CONFIG
         */
        res = nrf5_wait_for_nvmc(chip);
        if (res != ERROR_OK)
                LOG_ERROR("Read only enable did not complete");

        return res;
}

static int nrf5_nvmc_generic_erase(struct nrf5_info *chip,
                               uint32_t erase_register, uint32_t erase_value)
{
        int res;

        res = nrf5_nvmc_erase_enable(chip);
        if (res != ERROR_OK)
                goto error;

        res = target_write_u32(chip->target,
                               erase_register,
                               erase_value);
        if (res != ERROR_OK)
                goto set_read_only;

        res = nrf5_wait_for_nvmc(chip);
        if (res != ERROR_OK)
                goto set_read_only;

        return nrf5_nvmc_read_only(chip);

set_read_only:
        nrf5_nvmc_read_only(chip);
error:
        LOG_ERROR("Failed to erase reg: 0x%08"PRIx32" val: 0x%08"PRIx32,
                  erase_register, erase_value);
        return ERROR_FAIL;
}

static int nrf5_protect_check_clenr0(struct flash_bank *bank)
{
        int res;
        uint32_t clenr0;

        struct nrf5_bank *nbank = bank->driver_priv;
        assert(nbank);
        struct nrf5_info *chip = nbank->chip;
        assert(chip);

        res = target_read_u32(chip->target, NRF51_FICR_CLENR0,
                              &clenr0);
        if (res != ERROR_OK) {
                LOG_ERROR("Couldn't read code region 0 size[FICR]");
                return res;
        }

        if (clenr0 == 0xFFFFFFFF) {
                res = target_read_u32(chip->target, NRF51_UICR_CLENR0,
                                      &clenr0);
                if (res != ERROR_OK) {
                        LOG_ERROR("Couldn't read code region 0 size[UICR]");
                        return res;
                }
        }

        for (unsigned int i = 0; i < bank->num_sectors; i++)
                bank->sectors[i].is_protected =
                        clenr0 != 0xFFFFFFFF && bank->sectors[i].offset < clenr0;

        return ERROR_OK;
}

static int nrf5_protect_check_bprot(struct flash_bank *bank)
{
        struct nrf5_bank *nbank = bank->driver_priv;
        assert(nbank);
        struct nrf5_info *chip = nbank->chip;
        assert(chip);

        static uint32_t nrf5_bprot_offsets[4] = { 0x600, 0x604, 0x610, 0x614 };
        uint32_t bprot_reg = 0;
        int res;

        for (unsigned int i = 0; i < bank->num_sectors; i++) {
                unsigned int bit = i % 32;
                if (bit == 0) {
                        unsigned int n_reg = i / 32;
                        if (n_reg >= ARRAY_SIZE(nrf5_bprot_offsets))
                                break;

                        res = target_read_u32(chip->target, NRF5_BPROT_BASE + nrf5_bprot_offsets[n_reg], &bprot_reg);
                        if (res != ERROR_OK)
                                return res;
                }
                bank->sectors[i].is_protected = (bprot_reg & (1 << bit)) ? 1 : 0;
        }
        return ERROR_OK;
}

static int nrf5_protect_check(struct flash_bank *bank)
{
        /* UICR cannot be write protected so just return early */
        if (bank->base == NRF5_UICR_BASE)
                return ERROR_OK;

        struct nrf5_bank *nbank = bank->driver_priv;
        assert(nbank);
        struct nrf5_info *chip = nbank->chip;
        assert(chip);

        if (chip->features & NRF5_FEATURE_BPROT)
                return nrf5_protect_check_bprot(bank);

        if (chip->features & NRF5_FEATURE_SERIES_51)
                return nrf5_protect_check_clenr0(bank);

        LOG_WARNING("Flash protection of this nRF device is not supported");
        return ERROR_FLASH_OPER_UNSUPPORTED;
}

static int nrf5_protect_clenr0(struct flash_bank *bank, int set, unsigned int first,
                unsigned int last)
{
        int res;
        uint32_t clenr0, ppfc;

        struct nrf5_bank *nbank = bank->driver_priv;
        assert(nbank);
        struct nrf5_info *chip = nbank->chip;
        assert(chip);

        if (first != 0) {
                LOG_ERROR("Code region 0 must start at the beginning of the bank");
                return ERROR_FAIL;
        }

        res = target_read_u32(chip->target, NRF51_FICR_PPFC,
                              &ppfc);
        if (res != ERROR_OK) {
                LOG_ERROR("Couldn't read PPFC register");
                return res;
        }

        if ((ppfc & 0xFF) == 0x00) {
                LOG_ERROR("Code region 0 size was pre-programmed at the factory, can't change flash protection settings");
                return ERROR_FAIL;
        }

        res = target_read_u32(chip->target, NRF51_UICR_CLENR0,
                              &clenr0);
        if (res != ERROR_OK) {
                LOG_ERROR("Couldn't read code region 0 size from UICR");
                return res;
        }

        if (!set || clenr0 != 0xFFFFFFFF) {
                LOG_ERROR("You need to perform chip erase before changing the protection settings");
                return ERROR_FAIL;
        }

        res = nrf5_nvmc_write_enable(chip);
        if (res != ERROR_OK)
                goto error;

        clenr0 = bank->sectors[last].offset + bank->sectors[last].size;
        res = target_write_u32(chip->target, NRF51_UICR_CLENR0, clenr0);

        int res2 = nrf5_wait_for_nvmc(chip);

        if (res == ERROR_OK)
                res = res2;

        if (res == ERROR_OK)
                LOG_INFO("A reset or power cycle is required for the new protection settings to take effect.");
        else
                LOG_ERROR("Couldn't write code region 0 size to UICR");

error:
        nrf5_nvmc_read_only(chip);

        return res;
}

static int nrf5_protect(struct flash_bank *bank, int set, unsigned int first,
                unsigned int last)
{
        /* UICR cannot be write protected so just bail out early */
        if (bank->base == NRF5_UICR_BASE) {
                LOG_ERROR("UICR page does not support protection");
                return ERROR_FLASH_OPER_UNSUPPORTED;
        }

        if (bank->target->state != TARGET_HALTED) {
                LOG_ERROR("Target not halted");
                return ERROR_TARGET_NOT_HALTED;
        }

        struct nrf5_bank *nbank = bank->driver_priv;
        assert(nbank);
        struct nrf5_info *chip = nbank->chip;
        assert(chip);

        if (chip->features & NRF5_FEATURE_SERIES_51)
                return nrf5_protect_clenr0(bank, set, first, last);

        LOG_ERROR("Flash protection setting is not supported on this nRF5 device");
        return ERROR_FLASH_OPER_UNSUPPORTED;
}

static bool nrf5_info_variant_to_str(uint32_t variant, char *bf)
{
        uint8_t b[4];

        h_u32_to_be(b, variant);
        if (isalnum(b[0]) && isalnum(b[1]) && isalnum(b[2]) && isalnum(b[3])) {
                memcpy(bf, b, 4);
                bf[4] = 0;
                return true;
        }

        strcpy(bf, "xxxx");
        return false;
}

static const char *nrf5_decode_info_package(uint32_t package)
{
        for (size_t i = 0; i < ARRAY_SIZE(nrf52_packages_table); i++) {
                if (nrf52_packages_table[i].package == package)
                        return nrf52_packages_table[i].code;
        }
        return "xx";
}

static int get_nrf5_chip_type_str(const struct nrf5_info *chip, char *buf, unsigned int buf_size)
{
        int res;
        if (chip->spec) {
                res = snprintf(buf, buf_size, "nRF%s-%s(build code: %s)",
                                chip->spec->part, chip->spec->variant, chip->spec->build_code);
        } else if (chip->ficr_info_valid) {
                char variant[5];
                nrf5_info_variant_to_str(chip->ficr_info.variant, variant);
                res = snprintf(buf, buf_size, "nRF%" PRIx32 "-%s%.2s(build code: %s)",
                                chip->ficr_info.part,
                                nrf5_decode_info_package(chip->ficr_info.package),
                                variant, &variant[2]);
        } else {
                res = snprintf(buf, buf_size, "nRF51xxx (HWID 0x%04" PRIx16 ")", chip->hwid);
        }

        /* safety: */
        if (res <= 0 || (unsigned int)res >= buf_size) {
                LOG_ERROR("BUG: buffer problem in %s", __func__);
                return ERROR_FAIL;
        }
        return ERROR_OK;
}

static int nrf5_info(struct flash_bank *bank, struct command_invocation *cmd)
{
        struct nrf5_bank *nbank = bank->driver_priv;
        assert(nbank);
        struct nrf5_info *chip = nbank->chip;
        assert(chip);

        char chip_type_str[256];
        if (get_nrf5_chip_type_str(chip, chip_type_str, sizeof(chip_type_str)) != ERROR_OK)
                return ERROR_FAIL;

        command_print_sameline(cmd, "%s %ukB Flash, %ukB RAM",
                        chip_type_str, chip->flash_size_kb, chip->ram_size_kb);
        return ERROR_OK;
}

static int nrf5_read_ficr_info(struct nrf5_info *chip)
{
        int res;
        struct target *target = chip->target;

        chip->ficr_info_valid = false;

        res = target_read_u32(target, NRF5_FICR_INFO_PART, &chip->ficr_info.part);
        if (res != ERROR_OK) {
                LOG_DEBUG("Couldn't read FICR INFO.PART register");
                return res;
        }

        uint32_t series = chip->ficr_info.part & 0xfffff000;
        switch (series) {
        case 0x51000:
                chip->features = NRF5_FEATURE_SERIES_51;
                break;

        case 0x52000:
                chip->features = NRF5_FEATURE_SERIES_52;

                switch (chip->ficr_info.part) {
                case 0x52805:
                case 0x52810:
                case 0x52811:
                case 0x52832:
                        chip->features |= NRF5_FEATURE_BPROT;
                        break;

                case 0x52820:
                case 0x52833:
                case 0x52840:
                        chip->features |= NRF5_FEATURE_ACL_PROT;
                        break;
                }
                break;

        default:
                LOG_DEBUG("FICR INFO likely not implemented. Invalid PART value 0x%08"
                                PRIx32, chip->ficr_info.part);
                return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
        }

        /* Now we know the device has FICR INFO filled by something relevant:
         * Although it is not documented, the tested nRF51 rev 3 devices
         * have FICR INFO.PART, RAM and FLASH of the same format as nRF52.
         * VARIANT and PACKAGE coding is unknown for a nRF51 device.
         * nRF52 devices have FICR INFO documented and always filled. */

        res = target_read_u32(target, NRF5_FICR_INFO_VARIANT, &chip->ficr_info.variant);
        if (res != ERROR_OK)
                return res;

        res = target_read_u32(target, NRF5_FICR_INFO_PACKAGE, &chip->ficr_info.package);
        if (res != ERROR_OK)
                return res;

        res = target_read_u32(target, NRF5_FICR_INFO_RAM, &chip->ficr_info.ram);
        if (res != ERROR_OK)
                return res;

        res = target_read_u32(target, NRF5_FICR_INFO_FLASH, &chip->ficr_info.flash);
        if (res != ERROR_OK)
                return res;

        chip->ficr_info_valid = true;
        return ERROR_OK;
}

static int nrf5_get_ram_size(struct target *target, uint32_t *ram_size)
{
        int res;

        *ram_size = 0;

        uint32_t numramblock;
        res = target_read_u32(target, NRF51_FICR_NUMRAMBLOCK, &numramblock);
        if (res != ERROR_OK) {
                LOG_DEBUG("Couldn't read FICR NUMRAMBLOCK register");
                return res;
        }

        if (numramblock < 1 || numramblock > 4) {
                LOG_DEBUG("FICR NUMRAMBLOCK strange value %" PRIx32, numramblock);
                return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
        }

        for (unsigned int i = 0; i < numramblock; i++) {
                uint32_t sizeramblock;
                res = target_read_u32(target, NRF51_FICR_SIZERAMBLOCK0 + sizeof(uint32_t)*i, &sizeramblock);
                if (res != ERROR_OK) {
                        LOG_DEBUG("Couldn't read FICR NUMRAMBLOCK register");
                        return res;
                }
                if (sizeramblock < 1024 || sizeramblock > 65536)
                        LOG_DEBUG("FICR SIZERAMBLOCK strange value %" PRIx32, sizeramblock);
                else
                        *ram_size += sizeramblock;
        }
        return res;
}

static int nrf5_probe(struct flash_bank *bank)
{
        int res;

        struct nrf5_bank *nbank = bank->driver_priv;
        assert(nbank);
        struct nrf5_info *chip = nbank->chip;
        assert(chip);
        struct target *target = chip->target;

        uint32_t configid;
        res = target_read_u32(target, NRF5_FICR_CONFIGID, &configid);
        if (res != ERROR_OK) {
                LOG_ERROR("Couldn't read CONFIGID register");
                return res;
        }

        /* HWID is stored in the lower two bytes of the CONFIGID register */
        chip->hwid = configid & 0xFFFF;

        /* guess a nRF51 series if the device has no FICR INFO and we don't know HWID */
        chip->features = NRF5_FEATURE_SERIES_51;

        /* Don't bail out on error for the case that some old engineering
         * sample has FICR INFO registers unreadable. We can proceed anyway. */
        (void)nrf5_read_ficr_info(chip);

        chip->spec = NULL;
        for (size_t i = 0; i < ARRAY_SIZE(nrf5_known_devices_table); i++) {
                if (chip->hwid == nrf5_known_devices_table[i].hwid) {
                        chip->spec = &nrf5_known_devices_table[i];
                        chip->features = chip->spec->features;
                        break;
                }
        }

        if (chip->spec && chip->ficr_info_valid) {
                /* check if HWID table gives the same part as FICR INFO */
                if (chip->ficr_info.part != strtoul(chip->spec->part, NULL, 16))
                        LOG_WARNING("HWID 0x%04" PRIx32 " mismatch: FICR INFO.PART %"
                                                PRIx32, chip->hwid, chip->ficr_info.part);
        }

        if (chip->ficr_info_valid) {
                chip->ram_size_kb = chip->ficr_info.ram;
        } else {
                uint32_t ram_size;
                nrf5_get_ram_size(target, &ram_size);
                chip->ram_size_kb = ram_size / 1024;
        }

        /* The value stored in NRF5_FICR_CODEPAGESIZE is the number of bytes in one page of FLASH. */
        uint32_t flash_page_size;
        res = target_read_u32(chip->target, NRF5_FICR_CODEPAGESIZE,
                                &flash_page_size);
        if (res != ERROR_OK) {
                LOG_ERROR("Couldn't read code page size");
                return res;
        }

        /* Note the register name is misleading,
         * NRF5_FICR_CODESIZE is the number of pages in flash memory, not the number of bytes! */
        uint32_t num_sectors;
        res = target_read_u32(chip->target, NRF5_FICR_CODESIZE, &num_sectors);
        if (res != ERROR_OK) {
                LOG_ERROR("Couldn't read code memory size");
                return res;
        }

        chip->flash_size_kb = num_sectors * flash_page_size / 1024;

        if (!chip->bank[0].probed && !chip->bank[1].probed) {
                char chip_type_str[256];
                if (get_nrf5_chip_type_str(chip, chip_type_str, sizeof(chip_type_str)) != ERROR_OK)
                        return ERROR_FAIL;
                const bool device_is_unknown = (!chip->spec && !chip->ficr_info_valid);
                LOG_INFO("%s%s %ukB Flash, %ukB RAM",
                                device_is_unknown ? "Unknown device: " : "",
                                chip_type_str,
                                chip->flash_size_kb,
                                chip->ram_size_kb);
        }

        free(bank->sectors);

        if (bank->base == NRF5_FLASH_BASE) {
                /* Sanity check */
                if (chip->spec && chip->flash_size_kb != chip->spec->flash_size_kb)
                        LOG_WARNING("Chip's reported Flash capacity does not match expected one");
                if (chip->ficr_info_valid && chip->flash_size_kb != chip->ficr_info.flash)
                        LOG_WARNING("Chip's reported Flash capacity does not match FICR INFO.FLASH");

                bank->num_sectors = num_sectors;
                bank->size = num_sectors * flash_page_size;

                bank->sectors = alloc_block_array(0, flash_page_size, num_sectors);
                if (!bank->sectors)
                        return ERROR_FAIL;

                chip->bank[0].probed = true;

        } else {
                bank->num_sectors = 1;
                bank->size = flash_page_size;

                bank->sectors = alloc_block_array(0, flash_page_size, num_sectors);
                if (!bank->sectors)
                        return ERROR_FAIL;

                bank->sectors[0].is_protected = 0;

                chip->bank[1].probed = true;
        }

        return ERROR_OK;
}

static int nrf5_auto_probe(struct flash_bank *bank)
{
        if (nrf5_bank_is_probed(bank))
                return ERROR_OK;

        return nrf5_probe(bank);
}

static int nrf5_erase_all(struct nrf5_info *chip)
{
        LOG_DEBUG("Erasing all non-volatile memory");
        return nrf5_nvmc_generic_erase(chip,
                                        NRF5_NVMC_ERASEALL,
                                        0x00000001);
}

static int nrf5_erase_page(struct flash_bank *bank,
                                                        struct nrf5_info *chip,
                                                        struct flash_sector *sector)
{
        int res;

        LOG_DEBUG("Erasing page at 0x%"PRIx32, sector->offset);

        if (bank->base == NRF5_UICR_BASE) {
                if (chip->features & NRF5_FEATURE_SERIES_51) {
                        uint32_t ppfc;
                        res = target_read_u32(chip->target, NRF51_FICR_PPFC,
                                      &ppfc);
                        if (res != ERROR_OK) {
                                LOG_ERROR("Couldn't read PPFC register");
                                return res;
                        }

                        if ((ppfc & 0xFF) == 0xFF) {
                                /* We can't erase the UICR.  Double-check to
                                   see if it's already erased before complaining. */
                                default_flash_blank_check(bank);
                                if (sector->is_erased == 1)
                                        return ERROR_OK;

                                LOG_ERROR("The chip was not pre-programmed with SoftDevice stack and UICR cannot be erased separately. Please issue mass erase before trying to write to this region");
                                return ERROR_FAIL;
                        }
                }

                res = nrf5_nvmc_generic_erase(chip,
                                               NRF5_NVMC_ERASEUICR,
                                               0x00000001);


        } else {
                res = nrf5_nvmc_generic_erase(chip,
                                               NRF5_NVMC_ERASEPAGE,
                                               sector->offset);
        }

        return res;
}

/* Start a low level flash write for the specified region */
static int nrf5_ll_flash_write(struct nrf5_info *chip, uint32_t address, const uint8_t *buffer, uint32_t bytes)
{
        struct target *target = chip->target;
        uint32_t buffer_size = 8192;
        struct working_area *write_algorithm;
        struct working_area *source;
        struct reg_param reg_params[6];
        struct armv7m_algorithm armv7m_info;
        int retval = ERROR_OK;

        static const uint8_t nrf5_flash_write_code[] = {
#include "../../../contrib/loaders/flash/nrf5/nrf5.inc"
        };

        LOG_DEBUG("Writing buffer to flash address=0x%"PRIx32" bytes=0x%"PRIx32, address, bytes);
        assert(bytes % 4 == 0);

        /* allocate working area with flash programming code */
        if (target_alloc_working_area(target, sizeof(nrf5_flash_write_code),
                        &write_algorithm) != ERROR_OK) {
                LOG_WARNING("no working area available, falling back to slow memory writes");

                for (; bytes > 0; bytes -= 4) {
                        retval = target_write_memory(target, address, 4, 1, buffer);
                        if (retval != ERROR_OK)
                                return retval;

                        retval = nrf5_wait_for_nvmc(chip);
                        if (retval != ERROR_OK)
                                return retval;

                        address += 4;
                        buffer += 4;
                }

                return ERROR_OK;
        }

        retval = target_write_buffer(target, write_algorithm->address,
                                sizeof(nrf5_flash_write_code),
                                nrf5_flash_write_code);
        if (retval != ERROR_OK)
                return retval;

        /* memory buffer */
        while (target_alloc_working_area(target, buffer_size, &source) != ERROR_OK) {
                buffer_size /= 2;
                buffer_size &= ~3UL; /* Make sure it's 4 byte aligned */
                if (buffer_size <= 256) {
                        /* free working area, write algorithm already allocated */
                        target_free_working_area(target, write_algorithm);

                        LOG_WARNING("No large enough working area available, can't do block memory writes");
                        return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
                }
        }

        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); /* byte count */
        init_reg_param(&reg_params[1], "r1", 32, PARAM_OUT);    /* buffer start */
        init_reg_param(&reg_params[2], "r2", 32, PARAM_OUT);    /* buffer end */
        init_reg_param(&reg_params[3], "r3", 32, PARAM_IN_OUT); /* target address */
        init_reg_param(&reg_params[4], "r6", 32, PARAM_OUT);    /* watchdog refresh value */
        init_reg_param(&reg_params[5], "r7", 32, PARAM_OUT);    /* watchdog refresh register address */

        buf_set_u32(reg_params[0].value, 0, 32, bytes);
        buf_set_u32(reg_params[1].value, 0, 32, source->address);
        buf_set_u32(reg_params[2].value, 0, 32, source->address + source->size);
        buf_set_u32(reg_params[3].value, 0, 32, address);
        buf_set_u32(reg_params[4].value, 0, 32, WATCHDOG_REFRESH_VALUE);
        buf_set_u32(reg_params[5].value, 0, 32, WATCHDOG_REFRESH_REGISTER);

        retval = target_run_flash_async_algorithm(target, buffer, bytes/4, 4,
                        0, NULL,
                        ARRAY_SIZE(reg_params), reg_params,
                        source->address, source->size,
                        write_algorithm->address, write_algorithm->address + sizeof(nrf5_flash_write_code) - 2,
                        &armv7m_info);

        target_free_working_area(target, source);
        target_free_working_area(target, write_algorithm);

        destroy_reg_param(&reg_params[0]);
        destroy_reg_param(&reg_params[1]);
        destroy_reg_param(&reg_params[2]);
        destroy_reg_param(&reg_params[3]);
        destroy_reg_param(&reg_params[4]);
        destroy_reg_param(&reg_params[5]);

        return retval;
}

static int nrf5_write(struct flash_bank *bank, const uint8_t *buffer,
                                        uint32_t offset, uint32_t count)
{
        int res;

        if (bank->target->state != TARGET_HALTED) {
                LOG_ERROR("Target not halted");
                return ERROR_TARGET_NOT_HALTED;
        }

        struct nrf5_bank *nbank = bank->driver_priv;
        assert(nbank);
        struct nrf5_info *chip = nbank->chip;
        assert(chip);

        assert(offset % 4 == 0);
        assert(count % 4 == 0);

        /* UICR CLENR0 based protection used on nRF51 is somewhat clumsy:
         * RM reads: Code running from code region 1 will not be able to write
         * to code region 0.
         * Unfortunately the flash loader running from RAM can write to both
         * code regions without any hint the protection is violated.
         *
         * Update protection state and check if any flash sector to be written
         * is protected. */
        if (chip->features & NRF5_FEATURE_SERIES_51) {

                res = nrf5_protect_check_clenr0(bank);
                if (res != ERROR_OK)
                        return res;

                for (unsigned int sector = 0; sector < bank->num_sectors; sector++) {
                        struct flash_sector *bs = &bank->sectors[sector];

                        /* Start offset in or before this sector? */
                        /* End offset in or behind this sector? */
                        if ((offset < (bs->offset + bs->size))
                                        && ((offset + count - 1) >= bs->offset)
                                        && bs->is_protected == 1) {
                                LOG_ERROR("Write refused, sector %d is protected", sector);
                                return ERROR_FLASH_PROTECTED;
                        }
                }
        }

        res = nrf5_nvmc_write_enable(chip);
        if (res != ERROR_OK)
                goto error;

        res = nrf5_ll_flash_write(chip, bank->base + offset, buffer, count);
        if (res != ERROR_OK)
                goto error;

        return nrf5_nvmc_read_only(chip);

error:
        nrf5_nvmc_read_only(chip);
        LOG_ERROR("Failed to write to nrf5 flash");
        return res;
}

static int nrf5_erase(struct flash_bank *bank, unsigned int first,
                unsigned int last)
{
        int res;

        if (bank->target->state != TARGET_HALTED) {
                LOG_ERROR("Target not halted");
                return ERROR_TARGET_NOT_HALTED;
        }

        struct nrf5_bank *nbank = bank->driver_priv;
        assert(nbank);
        struct nrf5_info *chip = nbank->chip;
        assert(chip);

        /* UICR CLENR0 based protection used on nRF51 prevents erase
         * absolutely silently. NVMC has no flag to indicate the protection
         * was violated.
         *
         * Update protection state and check if any flash sector to be erased
         * is protected. */
        if (chip->features & NRF5_FEATURE_SERIES_51) {

                res = nrf5_protect_check_clenr0(bank);
                if (res != ERROR_OK)
                        return res;
        }

        /* For each sector to be erased */
        for (unsigned int s = first; s <= last; s++) {

                if (chip->features & NRF5_FEATURE_SERIES_51
                                && bank->sectors[s].is_protected == 1) {
                        LOG_ERROR("Flash sector %d is protected", s);
                        return ERROR_FLASH_PROTECTED;
                }

                res = nrf5_erase_page(bank, chip, &bank->sectors[s]);
                if (res != ERROR_OK) {
                        LOG_ERROR("Error erasing sector %d", s);
                        return res;
                }
        }

        return ERROR_OK;
}

static void nrf5_free_driver_priv(struct flash_bank *bank)
{
        struct nrf5_bank *nbank = bank->driver_priv;
        assert(nbank);
        struct nrf5_info *chip = nbank->chip;
        if (!chip)
                return;

        chip->refcount--;
        if (chip->refcount == 0) {
                free(chip);
                bank->driver_priv = NULL;
        }
}

static struct nrf5_info *nrf5_get_chip(struct target *target)
{
        struct flash_bank *bank_iter;

        /* iterate over nrf5 banks of same target */
        for (bank_iter = flash_bank_list(); bank_iter; bank_iter = bank_iter->next) {
                if (bank_iter->driver != &nrf5_flash && bank_iter->driver != &nrf51_flash)
                        continue;

                if (bank_iter->target != target)
                        continue;

                struct nrf5_bank *nbank = bank_iter->driver_priv;
                if (!nbank)
                        continue;

                if (nbank->chip)
                        return nbank->chip;
        }
        return NULL;
}

FLASH_BANK_COMMAND_HANDLER(nrf5_flash_bank_command)
{
        struct nrf5_info *chip;
        struct nrf5_bank *nbank = NULL;

        if (bank->driver == &nrf51_flash)
                LOG_WARNING("Flash driver 'nrf51' is deprecated! Use 'nrf5' instead.");

        switch (bank->base) {
        case NRF5_FLASH_BASE:
        case NRF5_UICR_BASE:
                break;
        default:
                LOG_ERROR("Invalid bank address " TARGET_ADDR_FMT, bank->base);
                return ERROR_FAIL;
        }

        chip = nrf5_get_chip(bank->target);
        if (!chip) {
                /* Create a new chip */
                chip = calloc(1, sizeof(*chip));
                if (!chip)
                        return ERROR_FAIL;

                chip->target = bank->target;
        }

        switch (bank->base) {
        case NRF5_FLASH_BASE:
                nbank = &chip->bank[0];
                break;
        case NRF5_UICR_BASE:
                nbank = &chip->bank[1];
                break;
        }
        assert(nbank);

        chip->refcount++;
        nbank->chip = chip;
        nbank->probed = false;
        bank->driver_priv = nbank;
        bank->write_start_alignment = bank->write_end_alignment = 4;

        return ERROR_OK;
}

COMMAND_HANDLER(nrf5_handle_mass_erase_command)
{
        int res;
        struct flash_bank *bank = NULL;
        struct target *target = get_current_target(CMD_CTX);

        res = get_flash_bank_by_addr(target, NRF5_FLASH_BASE, true, &bank);
        if (res != ERROR_OK)
                return res;

        assert(bank);

        if (target->state != TARGET_HALTED) {
                LOG_ERROR("Target not halted");
                return ERROR_TARGET_NOT_HALTED;
        }

        struct nrf5_bank *nbank = bank->driver_priv;
        assert(nbank);
        struct nrf5_info *chip = nbank->chip;
        assert(chip);

        if (chip->features & NRF5_FEATURE_SERIES_51) {
                uint32_t ppfc;
                res = target_read_u32(target, NRF51_FICR_PPFC,
                              &ppfc);
                if (res != ERROR_OK) {
                        LOG_ERROR("Couldn't read PPFC register");
                        return res;
                }

                if ((ppfc & 0xFF) == 0x00) {
                        LOG_ERROR("Code region 0 size was pre-programmed at the factory, "
                                  "mass erase command won't work.");
                        return ERROR_FAIL;
                }
        }

        res = nrf5_erase_all(chip);
        if (res == ERROR_OK) {
                LOG_INFO("Mass erase completed.");
                if (chip->features & NRF5_FEATURE_SERIES_51)
                        LOG_INFO("A reset or power cycle is required if the flash was protected before.");

        } else {
                LOG_ERROR("Failed to erase the chip");
        }

        return res;
}


static const struct command_registration nrf5_exec_command_handlers[] = {
        {
                .name           = "mass_erase",
                .handler        = nrf5_handle_mass_erase_command,
                .mode           = COMMAND_EXEC,
                .help           = "Erase all flash contents of the chip.",
                .usage          = "",
        },
        COMMAND_REGISTRATION_DONE
};

static const struct command_registration nrf5_command_handlers[] = {
        {
                .name   = "nrf5",
                .mode   = COMMAND_ANY,
                .help   = "nrf5 flash command group",
                .usage  = "",
                .chain  = nrf5_exec_command_handlers,
        },
        {
                .name   = "nrf51",
                .mode   = COMMAND_ANY,
                .help   = "nrf51 flash command group",
                .usage  = "",
                .chain  = nrf5_exec_command_handlers,
        },
        COMMAND_REGISTRATION_DONE
};

const struct flash_driver nrf5_flash = {
        .name                   = "nrf5",
        .commands               = nrf5_command_handlers,
        .flash_bank_command     = nrf5_flash_bank_command,
        .info                   = nrf5_info,
        .erase                  = nrf5_erase,
        .protect                = nrf5_protect,
        .write                  = nrf5_write,
        .read                   = default_flash_read,
        .probe                  = nrf5_probe,
        .auto_probe             = nrf5_auto_probe,
        .erase_check            = default_flash_blank_check,
        .protect_check          = nrf5_protect_check,
        .free_driver_priv       = nrf5_free_driver_priv,
};

/* We need to retain the flash-driver name as well as the commands
 * for backwards compatibility */
const struct flash_driver nrf51_flash = {
        .name                   = "nrf51",
        .commands               = nrf5_command_handlers,
        .flash_bank_command     = nrf5_flash_bank_command,
        .info                   = nrf5_info,
        .erase                  = nrf5_erase,
        .protect                = nrf5_protect,
        .write                  = nrf5_write,
        .read                   = default_flash_read,
        .probe                  = nrf5_probe,
        .auto_probe             = nrf5_auto_probe,
        .erase_check            = default_flash_blank_check,
        .protect_check          = nrf5_protect_check,
        .free_driver_priv       = nrf5_free_driver_priv,
};