psoc4: support for Cypress PSoC 41xx/42xx family

New NOR flash driver was derived from stm32lx.
Procedure ocd_process_reset_inner is overriden in psoc4.cfg
to handle reset halt and system ROM peculiarities.

Change-Id: Ib835324412d106ad749e1351a8e18e6be34ca500
Signed-off-by: Tomas Vanek <vanekt@fbl.cz>
Reviewed-on: http://openocd.zylin.com/2282
Tested-by: jenkins
Reviewed-by: Paul Fertser <fercerpav@gmail.com>

1 files changed, 797 insertions, 0 deletions

diff --git a/src/flash/nor/psoc4.c b/src/flash/nor/psoc4.c
new file mode 100644
index 0000000..5bd00f5
--- /dev/null
+++ b/src/flash/nor/psoc4.c
@@ -0,0 +1,797 @@
+/***************************************************************************
+ *   Copyright (C) 2005 by Dominic Rath                                    *
+ *   Dominic.Rath@gmx.de                                                   *
+ *                                                                         *
+ *   Copyright (C) 2008 by Spencer Oliver                                  *
+ *   spen@spen-soft.co.uk                                                  *
+ *                                                                         *
+ *   Copyright (C) 2011 by Andreas Fritiofson                              *
+ *   andreas.fritiofson@gmail.com                                          *
+ *                                                                         *
+ *   Copyright (C) 2014 by Tomas Vanek (PSoC 4 support derived from STM32) *
+ *   vanekt@fbl.cz                                                         *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ *   This program is distributed in the hope that it will be useful,       *
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
+ *   GNU General Public License for more details.                          *
+ ***************************************************************************/
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "imp.h"
+#include <helper/binarybuffer.h>
+#include <jtag/jtag.h>
+#include <target/algorithm.h>
+#include <target/armv7m.h>
+
+/* device documets:
+
+ PSoC(R) 4: PSoC 4200 Family Datasheet
+	Document Number: 001-87197 Rev. *B  Revised August 29, 2013
+
+ PSoC 4100/4200 Family PSoC(R) 4 Architecture TRM
+	Document No. 001-85634 Rev. *C March 25, 2014
+
+ PSoC(R) 4 Registers TRM Spec.
+	Document No. 001-85847 Rev. *A June 25, 2013
+
+ CY8C41xx, CY8C42xx Programming Specifications
+	Document No. 001-81799 Rev. *C March 4, 2014
+*/
+
+/* register locations */
+#define PSOC4_CPUSS_SYSREQ	0x40000004
+#define PSOC4_CPUSS_SYSARG	0x40000008
+#define PSOC4_TEST_MODE		0x40030014
+#define PSOC4_SPCIF_GEOMETRY	0x400E0000
+
+#define PSOC4_SFLASH_MACRO	0x0ffff000
+
+/* constants */
+#define PSOC4_SROM_KEY1			0xb6
+#define PSOC4_SROM_KEY2			0xd3
+#define PSOC4_SROM_SYSREQ_BIT		(1<<31)
+#define PSOC4_SROM_HMASTER_BIT		(1<<30)
+#define PSOC4_SROM_PRIVILEGED_BIT	(1<<28)
+#define PSOC4_SROM_STATUS_SUCCEEDED	0xa0000000
+#define PSOC4_SROM_STATUS_FAILED	0xf0000000
+
+#define PSOC4_CMD_GET_SILICON_ID	0
+#define PSOC4_CMD_LOAD_LATCH		4
+#define PSOC4_CMD_WRITE_ROW		5
+#define PSOC4_CMD_PROGRAM_ROW		6
+#define PSOC4_CMD_ERASE_ALL		0xa
+#define PSOC4_CMD_CHECKSUM		0xb
+#define PSOC4_CMD_WRITE_PROTECTION	0xd
+
+#define PSOC4_CHIP_PROT_VIRGIN		0x0
+#define PSOC4_CHIP_PROT_OPEN		0x1
+#define PSOC4_CHIP_PROT_PROTECTED	0x2
+#define PSOC4_CHIP_PROT_KILL		0x4
+
+
+struct psoc4_chip_details {
+	uint16_t id;
+	const char *type;
+	const char *package;
+	uint16_t flash_size_in_kb;
+};
+
+/* list of PSoC 4 chips
+ * flash_size_in_kb is not necessary as it can be decoded from SPCIF_GEOMETRY
+ */
+const struct psoc4_chip_details psoc4_devices[] = {
+	/* 4200 series */
+	{ 0x04A6, "CY8C4245PVI-482", "SSOP-28", .flash_size_in_kb = 32 },
+	{ 0x04B6, "CY8C4245LQI-483", "QFN-40",  .flash_size_in_kb = 32 },
+	{ 0x04C8, "CY8C4245AXI-483", "TQFP-44", .flash_size_in_kb = 32 },
+	{ 0x04FB, "CY8C4245AXI-473", "TQFP-44", .flash_size_in_kb = 32 },
+	{ 0x04F0, "CY8C4244PVI-432", "SSOP-28", .flash_size_in_kb = 16 },
+	{ 0x04F1, "CY8C4244PVI-442", "SSOP-28", .flash_size_in_kb = 16 },
+	{ 0x04F6, "CY8C4244LQI-443", "QFN-40",  .flash_size_in_kb = 16 },
+	{ 0x04FA, "CY8C4244AXI-443", "TQFP-44", .flash_size_in_kb = 16 },
+
+	/* 4100 series */
+	{ 0x0410, "CY8C4124PVI-432", "SSOP-28", .flash_size_in_kb = 16 },
+	{ 0x0411, "CY8C4124PVI-442", "SSOP-28", .flash_size_in_kb = 16 },
+	{ 0x0416, "CY8C4124LQI-443", "QFN-40",  .flash_size_in_kb = 16 },
+	{ 0x041A, "CY8C4124AXI-443", "TQFP-44", .flash_size_in_kb = 16 },
+	{ 0x041B, "CY8C4125AXI-473", "TQFP-44", .flash_size_in_kb = 32 },
+	{ 0x0412, "CY8C4125PVI-482", "SSOP-28", .flash_size_in_kb = 32 },
+	{ 0x0417, "CY8C4125LQI-483", "QFN-40",  .flash_size_in_kb = 32 },
+	{ 0x041C, "CY8C4125AXI-483", "TQFP-44", .flash_size_in_kb = 32 },
+};
+
+
+struct psoc4_flash_bank {
+	uint16_t row_size;
+	uint32_t user_bank_size;
+	int probed;
+	uint32_t silicon_id;
+	uint8_t chip_protection;
+	uint16_t cmd_program_row;
+};
+
+
+static const struct psoc4_chip_details *psoc4_details_by_id(uint32_t silicon_id)
+{
+	const struct psoc4_chip_details *p = psoc4_devices;
+	unsigned int i;
+	uint16_t id = silicon_id >> 16; /* ignore die revision */
+	for (i = 0; i < sizeof(psoc4_devices)/sizeof(psoc4_devices[0]); i++, p++) {
+		if (p->id == id)
+			return p;
+	}
+	LOG_DEBUG("Unknown PSoC 4 device silicon id 0x%08" PRIx32 ".", silicon_id);
+	return NULL;
+}
+
+static const char *psoc4_decode_chip_protection(uint8_t protection)
+{
+	switch (protection) {
+	case PSOC4_CHIP_PROT_VIRGIN:
+		return "protection VIRGIN";
+	case PSOC4_CHIP_PROT_OPEN:
+		return "protection open";
+	case PSOC4_CHIP_PROT_PROTECTED:
+		return "PROTECTED";
+	case PSOC4_CHIP_PROT_KILL:
+		return "protection KILL";
+	default:
+		LOG_WARNING("Unknown protection state 0x%02" PRIx8 "", protection);
+		return "";
+	}
+}
+
+
+/* flash bank <name> psoc <base> <size> 0 0 <target#>
+ */
+FLASH_BANK_COMMAND_HANDLER(psoc4_flash_bank_command)
+{
+	struct psoc4_flash_bank *psoc4_info;
+
+	if (CMD_ARGC < 6)
+		return ERROR_COMMAND_SYNTAX_ERROR;
+
+	psoc4_info = calloc(1, sizeof(struct psoc4_flash_bank));
+
+	bank->driver_priv = psoc4_info;
+	psoc4_info->user_bank_size = bank->size;
+
+	return ERROR_OK;
+}
+
+
+/* PSoC 4 system ROM request
+ *  Setting SROM_SYSREQ_BIT in CPUSS_SYSREQ register runs NMI service
+ *  in sysrem ROM. Algorithm just waits for NMI to finish.
+ *  When sysreq_params_size == 0 only one parameter is passed in CPUSS_SYSARG register.
+ *  Otherwise address of memory parameter block is set in CPUSS_SYSARG
+ *  and the first parameter is written to the first word of parameter block
+ */
+static int psoc4_sysreq(struct target *target, uint8_t cmd, uint16_t cmd_param,
+		uint32_t *sysreq_params, uint32_t sysreq_params_size)
+{
+	struct working_area *sysreq_wait_algorithm;
+	struct working_area *sysreq_mem;
+
+	struct reg_param reg_params[1];
+	struct armv7m_algorithm armv7m_info;
+
+	int retval = ERROR_OK;
+
+	uint32_t param1 = PSOC4_SROM_KEY1
+			 | ((PSOC4_SROM_KEY2 + cmd) << 8)
+			 | (cmd_param << 16);
+
+	static uint8_t psoc4_sysreq_wait_code[] = {
+		/* system request NMI is served immediately after algo run
+       now we are done: break */
+		0x00, 0xbe,		/* bkpt 0 */
+	};
+
+	const int code_words = (sizeof(psoc4_sysreq_wait_code) + 3) / 4;
+					/* stack must be aligned */
+	const int stack_size = 196;
+	/* tested stack sizes on PSoC 4:
+		ERASE_ALL	144
+		PROGRAM_ROW	112
+		other sysreq	 68
+	*/
+
+	/* allocate area for sysreq wait code and stack */
+	if (target_alloc_working_area(target, code_words * 4 + stack_size,
+			&sysreq_wait_algorithm) != ERROR_OK) {
+		LOG_DEBUG("no working area for sysreq code");
+		return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
+	};
+
+	/* Write the code */
+	retval = target_write_buffer(target,
+			sysreq_wait_algorithm->address,
+			sizeof(psoc4_sysreq_wait_code),
+			psoc4_sysreq_wait_code);
+	if (retval != ERROR_OK) {
+		/* we already allocated the writing code, but failed to get a
+		 * buffer, free the algorithm */
+		goto cleanup_algo;
+	}
+
+	if (sysreq_params_size) {
+		/* Allocate memory for sysreq_params */
+		retval = target_alloc_working_area(target, sysreq_params_size, &sysreq_mem);
+		if (retval != ERROR_OK) {
+			LOG_WARNING("no working area for sysreq parameters");
+
+			/* we already allocated the writing code, but failed to get a
+			 * buffer, free the algorithm */
+			retval = ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
+			goto cleanup_algo;
+		}
+
+		/* Write sysreq_params */
+		sysreq_params[0] = param1;
+		retval = target_write_buffer(target, sysreq_mem->address,
+				sysreq_params_size, (uint8_t *)sysreq_params);
+		if (retval != ERROR_OK)
+			goto cleanup_mem;
+
+		/* Set address of sysreq parameters block */
+		retval = target_write_u32(target, PSOC4_CPUSS_SYSARG, sysreq_mem->address);
+		if (retval != ERROR_OK)
+			goto cleanup_mem;
+
+	} else {
+		/* Sysreq without memory block of parameters */
+		/* Set register parameter */
+		retval = target_write_u32(target, PSOC4_CPUSS_SYSARG, param1);
+		if (retval != ERROR_OK)
+			goto cleanup_mem;
+	}
+
+	armv7m_info.common_magic = ARMV7M_COMMON_MAGIC;
+	armv7m_info.core_mode = ARM_MODE_THREAD;
+
+	/* sysreq stack */
+	init_reg_param(&reg_params[0], "sp", 32, PARAM_OUT);
+	buf_set_u32(reg_params[0].value, 0, 32,
+		    sysreq_wait_algorithm->address + sysreq_wait_algorithm->size);
+
+	struct armv7m_common *armv7m = target_to_armv7m(target);
+	if (armv7m == NULL) {
+
+		/* something is very wrong if armv7m is NULL */
+		LOG_ERROR("unable to get armv7m target");
+		goto cleanup;
+	}
+
+	/* Set SROM request */
+	retval = target_write_u32(target, PSOC4_CPUSS_SYSREQ,
+				  PSOC4_SROM_SYSREQ_BIT | PSOC4_SROM_HMASTER_BIT | cmd);
+	if (retval != ERROR_OK)
+		goto cleanup;
+
+	/* Execute wait code */
+	retval = target_run_algorithm(target, 0, NULL,
+				sizeof(reg_params) / sizeof(*reg_params), reg_params,
+				sysreq_wait_algorithm->address, 0, 1000, &armv7m_info);
+	if (retval != ERROR_OK)
+		LOG_ERROR("sysreq wait code execution failed");
+
+cleanup:
+	destroy_reg_param(&reg_params[0]);
+
+cleanup_mem:
+	if (sysreq_params_size)
+		target_free_working_area(target, sysreq_mem);
+
+cleanup_algo:
+	target_free_working_area(target, sysreq_wait_algorithm);
+
+	return retval;
+}
+
+
+/* helper routine to get silicon ID from a PSoC 4 chip */
+static int psoc4_get_silicon_id(struct target *target, uint32_t *silicon_id, uint8_t *protection)
+{
+	uint32_t params = PSOC4_SROM_KEY1
+			 | ((PSOC4_SROM_KEY2 + PSOC4_CMD_GET_SILICON_ID) << 8);
+	uint32_t part0, part1;
+
+	int retval = psoc4_sysreq(target, PSOC4_CMD_GET_SILICON_ID, 0, NULL, 0);
+	if (retval != ERROR_OK)
+		return retval;
+
+	retval = target_read_u32(target, PSOC4_CPUSS_SYSARG, &part0);
+	if (retval != ERROR_OK)
+		return retval;
+
+	if (part0 == params) {
+		LOG_ERROR("sysreq silicon id request not served");
+		return ERROR_FAIL;
+	}
+
+	retval = target_read_u32(target, PSOC4_CPUSS_SYSREQ, &part1);
+	if (retval != ERROR_OK)
+		return retval;
+
+	uint32_t silicon = ((part0 & 0xffff) << 16)
+			| (((part0 >> 16) & 0xff) << 8)
+			| (part1 & 0xff);
+	uint8_t prot = (part1 >> 12) & 0xff;
+
+	if (silicon_id)
+			*silicon_id = silicon;
+	if (protection)
+			*protection = prot;
+
+	LOG_DEBUG("silicon id: 0x%" PRIx32 "", silicon);
+	LOG_DEBUG("protection: 0x%" PRIx8 "", prot);
+	return retval;
+}
+
+
+static int psoc4_protect_check(struct flash_bank *bank)
+{
+	struct target *target = bank->target;
+	struct psoc4_flash_bank *psoc4_info = bank->driver_priv;
+
+	uint32_t prot_addr = PSOC4_SFLASH_MACRO;
+	uint32_t protection;
+	int i, s;
+	int num_bits;
+	int retval = ERROR_OK;
+
+	num_bits = bank->num_sectors;
+
+	for (i = 0; i < num_bits; i += 32) {
+		retval = target_read_u32(target, prot_addr, &protection);
+		if (retval != ERROR_OK)
+			return retval;
+
+		prot_addr += 4;
+
+		for (s = 0; s < 32; s++) {
+			if (i + s >= num_bits)
+				break;
+			bank->sectors[i + s].is_protected = (protection & (1 << s)) ? 1 : 0;
+		}
+	}
+
+	retval = psoc4_get_silicon_id(target, NULL, &(psoc4_info->chip_protection));
+	return retval;
+}
+
+
+static int psoc4_mass_erase(struct flash_bank *bank)
+{
+	struct target *target = bank->target;
+	int i;
+
+	if (bank->target->state != TARGET_HALTED) {
+		LOG_ERROR("Target not halted");
+		return ERROR_TARGET_NOT_HALTED;
+	}
+
+	/* Call "Erase All" system ROM API */
+	uint32_t param;
+	int retval = psoc4_sysreq(target, PSOC4_CMD_ERASE_ALL,
+			0,
+			&param, sizeof(param));
+
+	if (retval == ERROR_OK)
+		/* set all sectors as erased */
+		for (i = 0; i < bank->num_sectors; i++)
+			bank->sectors[i].is_erased = 1;
+
+	return retval;
+}
+
+
+static int psoc4_erase(struct flash_bank *bank, int first, int last)
+{
+	struct psoc4_flash_bank *psoc4_info = bank->driver_priv;
+	if (psoc4_info->cmd_program_row == PSOC4_CMD_WRITE_ROW) {
+		LOG_INFO("Autoerase enabled, erase command ignored");
+		return ERROR_OK;
+	}
+
+	if ((first == 0) && (last == (bank->num_sectors - 1)))
+		return psoc4_mass_erase(bank);
+
+	LOG_ERROR("Only mass erase available");
+
+	return ERROR_FAIL;
+}
+
+
+static int psoc4_protect(struct flash_bank *bank, int set, int first, int last)
+{
+	struct target *target = bank->target;
+	struct psoc4_flash_bank *psoc4_info = bank->driver_priv;
+
+	if (psoc4_info->probed == 0)
+		return ERROR_FAIL;
+
+	if (target->state != TARGET_HALTED) {
+		LOG_ERROR("Target not halted");
+		return ERROR_TARGET_NOT_HALTED;
+	}
+
+	uint32_t *sysrq_buffer = NULL;
+	int retval;
+	int num_bits = bank->num_sectors;
+	const int param_sz = 8;
+	int prot_sz = num_bits / 8;
+	int chip_prot = PSOC4_CHIP_PROT_OPEN;
+	int flash_macro = 0; /* PSoC 42xx has only macro 0 */
+	int i;
+
+	sysrq_buffer = calloc(1, param_sz + prot_sz);
+	if (sysrq_buffer == NULL) {
+		LOG_ERROR("no memory for row buffer");
+		return ERROR_FAIL;
+	}
+
+	for (i = first; i < num_bits && i <= last; i++)
+		bank->sectors[i].is_protected = set;
+
+	uint32_t *p = sysrq_buffer + 2;
+	for (i = 0; i < num_bits; i++) {
+		if (bank->sectors[i].is_protected)
+			p[i / 32] |= 1 << (i % 32);
+	}
+
+	/* Call "Load Latch" system ROM API */
+	sysrq_buffer[1] = prot_sz - 1;
+	retval = psoc4_sysreq(target, PSOC4_CMD_LOAD_LATCH,
+			0,	/* Byte number in latch from what to write */
+			sysrq_buffer, param_sz + psoc4_info->row_size);
+	if (retval != ERROR_OK)
+		goto cleanup;
+
+	/* Call "Write Protection" system ROM API */
+	retval = psoc4_sysreq(target, PSOC4_CMD_WRITE_PROTECTION,
+			chip_prot | (flash_macro << 8), NULL, 0);
+cleanup:
+	if (retval != ERROR_OK)
+		psoc4_protect_check(bank);
+
+	if (sysrq_buffer)
+		free(sysrq_buffer);
+
+	return retval;
+}
+
+
+COMMAND_HANDLER(psoc4_handle_flash_autoerase_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 (ERROR_OK != retval)
+		return retval;
+
+	struct psoc4_flash_bank *psoc4_info = bank->driver_priv;
+	bool enable = psoc4_info->cmd_program_row == PSOC4_CMD_WRITE_ROW;
+
+	if (CMD_ARGC >= 2)
+		COMMAND_PARSE_ON_OFF(CMD_ARGV[1], enable);
+
+	if (enable) {
+		psoc4_info->cmd_program_row = PSOC4_CMD_WRITE_ROW;
+		LOG_INFO("Flash auto-erase enabled, non mass erase commands will be ignored.");
+	} else {
+		psoc4_info->cmd_program_row = PSOC4_CMD_PROGRAM_ROW;
+		LOG_INFO("Flash auto-erase disabled. Use psoc mass_erase before flash programming.");
+	}
+
+	return retval;
+}
+
+
+static int psoc4_write(struct flash_bank *bank, const uint8_t *buffer,
+		uint32_t offset, uint32_t count)
+{
+	struct psoc4_flash_bank *psoc4_info = bank->driver_priv;
+	struct target *target = bank->target;
+	uint32_t *sysrq_buffer = NULL;
+	int retval = ERROR_OK;
+	const int param_sz = 8;
+
+	if (bank->target->state != TARGET_HALTED) {
+		LOG_ERROR("Target not halted");
+		return ERROR_TARGET_NOT_HALTED;
+	}
+
+	if (offset & 0x1) {
+		LOG_ERROR("offset 0x%" PRIx32 " breaks required 2-byte alignment", offset);
+		return ERROR_FLASH_DST_BREAKS_ALIGNMENT;
+	}
+
+	sysrq_buffer = malloc(param_sz + psoc4_info->row_size);
+	if (sysrq_buffer == NULL) {
+		LOG_ERROR("no memory for row buffer");
+		return ERROR_FAIL;
+	}
+
+	uint8_t *row_buffer = (uint8_t *)sysrq_buffer + param_sz;
+	uint32_t row_num = offset / psoc4_info->row_size;
+	uint32_t row_offset = offset - row_num * psoc4_info->row_size;
+	if (row_offset)
+		memset(row_buffer, 0, row_offset);
+
+	bool save_poll = jtag_poll_get_enabled();
+	jtag_poll_set_enabled(false);
+
+	while (count) {
+		uint32_t chunk_size = psoc4_info->row_size - row_offset;
+		if (chunk_size > count) {
+			chunk_size = count;
+			memset(row_buffer + chunk_size, 0, psoc4_info->row_size - chunk_size);
+		}
+		memcpy(row_buffer + row_offset, buffer, chunk_size);
+		LOG_DEBUG("offset / row: 0x%" PRIx32 " / %d  size %d",
+				offset, row_offset, chunk_size);
+
+		/* Call "Load Latch" system ROM API */
+		sysrq_buffer[1] = psoc4_info->row_size - 1;
+		retval = psoc4_sysreq(target, PSOC4_CMD_LOAD_LATCH,
+				0,	/* Byte number in latch from what to write */
+				sysrq_buffer, param_sz + psoc4_info->row_size);
+		if (retval != ERROR_OK)
+			goto cleanup;
+
+		/* Call "Program Row" or "Write Row" system ROM API */
+		uint32_t sysrq_param;
+		retval = psoc4_sysreq(target, psoc4_info->cmd_program_row,
+				row_num & 0xffff,
+				&sysrq_param, sizeof(sysrq_param));
+		if (retval != ERROR_OK)
+			goto cleanup;
+
+		buffer += chunk_size;
+		row_num++;
+		row_offset = 0;
+		count -= chunk_size;
+	}
+
+cleanup:
+	jtag_poll_set_enabled(save_poll);
+
+	if (sysrq_buffer)
+		free(sysrq_buffer);
+
+	return retval;
+}
+
+
+static int psoc4_probe(struct flash_bank *bank)
+{
+	struct psoc4_flash_bank *psoc4_info = bank->driver_priv;
+	struct target *target = bank->target;
+	int i;
+	uint16_t flash_size_in_kb = 0;
+	uint16_t max_flash_size_in_kb;
+	uint32_t cpu_id;
+	uint32_t silicon_id;
+	int row_size;
+	uint32_t base_address = 0x00000000;
+	uint8_t protection;
+
+	if (target->state != TARGET_HALTED) {
+		LOG_ERROR("Target not halted");
+		return ERROR_TARGET_NOT_HALTED;
+	}
+
+	psoc4_info->probed = 0;
+	psoc4_info->cmd_program_row = PSOC4_CMD_PROGRAM_ROW;
+
+	/* Get the CPUID from the ARM Core
+	 * http://infocenter.arm.com/help/topic/com.arm.doc.ddi0432c/DDI0432C_cortex_m0_r0p0_trm.pdf 4.2.1 */
+	int retval = target_read_u32(target, 0xE000ED00, &cpu_id);
+	if (retval != ERROR_OK)
+		return retval;
+
+	LOG_DEBUG("cpu id = 0x%08" PRIx32 "", cpu_id);
+
+	/* set page size, protection granularity and max flash size depending on family */
+	switch ((cpu_id >> 4) & 0xFFF) {
+	case 0xc20: /* M0 -> PSoC4 */
+		row_size = 128;
+		max_flash_size_in_kb = 32;
+		break;
+	default:
+		LOG_WARNING("Cannot identify target as a PSoC 4 family.");
+		return ERROR_FAIL;
+	}
+
+	uint32_t spcif_geometry;
+	retval = target_read_u32(target, PSOC4_SPCIF_GEOMETRY, &spcif_geometry);
+	if (retval == ERROR_OK) {
+		row_size = 128 * ((spcif_geometry >> 22) & 3);
+		flash_size_in_kb = (spcif_geometry & 0xffff) * 256 / 1024;
+		LOG_INFO("SPCIF geometry: %d kb flash, row %d bytes.", flash_size_in_kb, row_size);
+	}
+
+	/* ST-Link v2 has some problem reading PSOC4_SPCIF_GEOMETRY
+		and an error is reported late. Dummy read gets this error. */
+	uint32_t dummy;
+	target_read_u32(target, PSOC4_CPUSS_SYSREQ, &dummy);
+
+	/* get silicon ID from target. */
+	retval = psoc4_get_silicon_id(target, &silicon_id, &protection);
+	if (retval != ERROR_OK)
+		return retval;
+
+	const struct psoc4_chip_details *details = psoc4_details_by_id(silicon_id);
+	if (details) {
+		LOG_INFO("%s device detected.", details->type);
+		if (flash_size_in_kb == 0)
+			flash_size_in_kb = details->flash_size_in_kb;
+		else if (flash_size_in_kb != details->flash_size_in_kb)
+			LOG_ERROR("Flash size mismatch");
+	}
+
+	psoc4_info->row_size = row_size;
+	psoc4_info->silicon_id = silicon_id;
+	psoc4_info->chip_protection = protection;
+
+	/* failed reading flash size or flash size invalid (early silicon),
+	 * default to max target family */
+	if (retval != ERROR_OK || flash_size_in_kb == 0xffff || flash_size_in_kb == 0) {
+		LOG_WARNING("PSoC 4 flash size failed, probe inaccurate - assuming %dk flash",
+			max_flash_size_in_kb);
+		flash_size_in_kb = max_flash_size_in_kb;
+	}
+
+	/* if the user sets the size manually then ignore the probed value
+	 * this allows us to work around devices that have a invalid flash size register value */
+	if (psoc4_info->user_bank_size) {
+		LOG_INFO("ignoring flash probed value, using configured bank size");
+		flash_size_in_kb = psoc4_info->user_bank_size / 1024;
+	}
+
+	LOG_INFO("flash size = %d kbytes", flash_size_in_kb);
+
+	/* did we assign flash size? */
+	assert(flash_size_in_kb != 0xffff);
+
+	/* calculate numbers of pages */
+	int num_rows = flash_size_in_kb * 1024 / row_size;
+
+	/* check that calculation result makes sense */
+	assert(num_rows > 0);
+
+	if (bank->sectors) {
+		free(bank->sectors);
+		bank->sectors = NULL;
+	}
+
+	bank->base = base_address;
+	bank->size = (num_rows * row_size);
+	bank->num_sectors = num_rows;
+	bank->sectors = malloc(sizeof(struct flash_sector) * num_rows);
+
+	for (i = 0; i < num_rows; i++) {
+		bank->sectors[i].offset = i * row_size;
+		bank->sectors[i].size = row_size;
+		bank->sectors[i].is_erased = -1;
+		bank->sectors[i].is_protected = 1;
+	}
+
+	LOG_INFO("flash bank set %d rows", num_rows);
+	psoc4_info->probed = 1;
+
+	return ERROR_OK;
+}
+
+static int psoc4_auto_probe(struct flash_bank *bank)
+{
+	struct psoc4_flash_bank *psoc4_info = bank->driver_priv;
+	if (psoc4_info->probed)
+		return ERROR_OK;
+	return psoc4_probe(bank);
+}
+
+
+static int get_psoc4_info(struct flash_bank *bank, char *buf, int buf_size)
+{
+	struct psoc4_flash_bank *psoc4_info = bank->driver_priv;
+	int printed = 0;
+
+	if (psoc4_info->probed == 0)
+		return ERROR_FAIL;
+
+	const struct psoc4_chip_details *details = psoc4_details_by_id(psoc4_info->silicon_id);
+
+	if (details)
+		printed = snprintf(buf, buf_size, "PSoC 4 %s rev 0x%04" PRIx16 " package %s",
+				details->type, psoc4_info->silicon_id & 0xffff, details->package);
+	else
+		printed = snprintf(buf, buf_size, "PSoC 4 silicon id 0x%08" PRIx32 "",
+				psoc4_info->silicon_id);
+
+	buf += printed;
+	buf_size -= printed;
+
+	const char *prot_txt = psoc4_decode_chip_protection(psoc4_info->chip_protection);
+	snprintf(buf, buf_size, " flash %d kb %s", bank->size / 1024, prot_txt);
+	return ERROR_OK;
+}
+
+
+COMMAND_HANDLER(psoc4_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 (ERROR_OK != retval)
+		return retval;
+
+	retval = psoc4_mass_erase(bank);
+	if (retval == ERROR_OK)
+		command_print(CMD_CTX, "psoc mass erase complete");
+	else
+		command_print(CMD_CTX, "psoc mass erase failed");
+
+	return retval;
+}
+
+
+static const struct command_registration psoc4_exec_command_handlers[] = {
+	{
+		.name = "mass_erase",
+		.handler = psoc4_handle_mass_erase_command,
+		.mode = COMMAND_EXEC,
+		.usage = "bank_id",
+		.help = "Erase entire flash device.",
+	},
+	{
+		.name = "flash_autoerase",
+		.handler = psoc4_handle_flash_autoerase_command,
+		.mode = COMMAND_EXEC,
+		.usage = "bank_id on|off",
+		.help = "Set autoerase mode for flash bank.",
+	},
+	COMMAND_REGISTRATION_DONE
+};
+
+static const struct command_registration psoc4_command_handlers[] = {
+	{
+		.name = "psoc4",
+		.mode = COMMAND_ANY,
+		.help = "PSoC 4 flash command group",
+		.usage = "",
+		.chain = psoc4_exec_command_handlers,
+	},
+	COMMAND_REGISTRATION_DONE
+};
+
+struct flash_driver psoc4_flash = {
+	.name = "psoc4",
+	.commands = psoc4_command_handlers,
+	.flash_bank_command = psoc4_flash_bank_command,
+	.erase = psoc4_erase,
+	.protect = psoc4_protect,
+	.write = psoc4_write,
+	.read = default_flash_read,
+	.probe = psoc4_probe,
+	.auto_probe = psoc4_auto_probe,
+	.erase_check = default_flash_blank_check,
+	.protect_check = psoc4_protect_check,
+	.info = get_psoc4_info,
+};