drivers/mtd/spi/ramtron.c - uboot/armada - Git at Google

 /*
  * (C) Copyright 2010
  * Reinhard Meyer, EMK Elektronik, reinhard.meyer@emk-elektronik.de
  *
  * See file CREDITS for list of people who contributed to this
  * project.
  *
  * 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.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  * MA 02111-1307 USA
  */

 /*
  * Note: RAMTRON SPI FRAMs are ferroelectric, nonvolatile RAMs
  * with an interface identical to SPI flash devices.
  * However since they behave like RAM there are no delays or
  * busy polls required. They can sustain read or write at the
  * allowed SPI bus speed, which can be 40 MHz for some devices.
  *
  * Unfortunately some RAMTRON devices do not have a means of
  * identifying them. They will leave the SO line undriven when
  * the READ-ID command is issued. It is therefore mandatory
  * that the MISO line has a proper pull-up, so that READ-ID
  * will return a row of 0xff. This 0xff pseudo-id will cause
  * probes by all vendor specific functions that are designed
  * to handle it. If the MISO line is not pulled up, READ-ID
  * could return any random noise, even mimicking another
  * device.
  *
  * We use CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC
  * to define which device will be assumed after a simple status
  * register verify. This method is prone to false positive
  * detection and should therefore be the last to be tried.
  * Enter it in the last position in the table in spi_flash.c!
  *
  * The define CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC both activates
  * compilation of the special handler and defines the device
  * to assume.
  */

 #include <common.h>
 #include <malloc.h>
 #include <spi_flash.h>
 #include "spi_flash_internal.h"

 /*
  * Properties of supported FRAMs
  * Note: speed is currently not used because we have no method to deliver that
  * value to the upper layers
  */
 struct ramtron_spi_fram_params {
 	u32	size;		/* size in bytes */
 	u8	addr_len;	/* number of address bytes */
 	u8	merge_cmd;	/* some address bits are in the command byte */
 	u8	id1;		/* device ID 1 (family, density) */
 	u8	id2;		/* device ID 2 (sub, rev, rsvd) */
 	u32	speed;		/* max. SPI clock in Hz */
 	const char *name;	/* name for display and/or matching */
 };

 struct ramtron_spi_fram {
 	struct spi_flash flash;
 	const struct ramtron_spi_fram_params *params;
 };

 static inline struct ramtron_spi_fram *to_ramtron_spi_fram(struct spi_flash
 							     *flash)
 {
 	return container_of(flash, struct ramtron_spi_fram, flash);
 }

 /*
  * table describing supported FRAM chips:
  * chips without RDID command must have the values 0xff for id1 and id2
  */
 static const struct ramtron_spi_fram_params ramtron_spi_fram_table[] = {
 	{
 		.size = 32*1024,
 		.addr_len = 2,
 		.merge_cmd = 0,
 		.id1 = 0x22,
 		.id2 = 0x00,
 		.speed = 40000000,
 		.name = "FM25V02",
 	},
 	{
 		.size = 32*1024,
 		.addr_len = 2,
 		.merge_cmd = 0,
 		.id1 = 0x22,
 		.id2 = 0x01,
 		.speed = 40000000,
 		.name = "FM25VN02",
 	},
 	{
 		.size = 64*1024,
 		.addr_len = 2,
 		.merge_cmd = 0,
 		.id1 = 0x23,
 		.id2 = 0x00,
 		.speed = 40000000,
 		.name = "FM25V05",
 	},
 	{
 		.size = 64*1024,
 		.addr_len = 2,
 		.merge_cmd = 0,
 		.id1 = 0x23,
 		.id2 = 0x01,
 		.speed = 40000000,
 		.name = "FM25VN05",
 	},
 	{
 		.size = 128*1024,
 		.addr_len = 3,
 		.merge_cmd = 0,
 		.id1 = 0x24,
 		.id2 = 0x00,
 		.speed = 40000000,
 		.name = "FM25V10",
 	},
 	{
 		.size = 128*1024,
 		.addr_len = 3,
 		.merge_cmd = 0,
 		.id1 = 0x24,
 		.id2 = 0x01,
 		.speed = 40000000,
 		.name = "FM25VN10",
 	},
 #ifdef CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC
 	{
 		.size = 256*1024,
 		.addr_len = 3,
 		.merge_cmd = 0,
 		.id1 = 0xff,
 		.id2 = 0xff,
 		.speed = 40000000,
 		.name = "FM25H20",
 	},
 #endif
 };

 static int ramtron_common(struct spi_flash *flash,
 		u32 offset, size_t len, void *buf, u8 command)
 {
 	struct ramtron_spi_fram *sn = to_ramtron_spi_fram(flash);
 	u8 cmd[4];
 	int cmd_len;
 	int ret;

 	if (sn->params->addr_len == 3 && sn->params->merge_cmd == 0) {
 		cmd[0] = command;
 		cmd[1] = offset >> 16;
 		cmd[2] = offset >> 8;
 		cmd[3] = offset;
 		cmd_len = 4;
 	} else if (sn->params->addr_len == 2 && sn->params->merge_cmd == 0) {
 		cmd[0] = command;
 		cmd[1] = offset >> 8;
 		cmd[2] = offset;
 		cmd_len = 3;
 	} else {
 		printf("SF: unsupported addr_len or merge_cmd\n");
 		return -1;
 	}

 	/* claim the bus */
 	ret = spi_claim_bus(flash->spi);
 	if (ret) {
 		debug("SF: Unable to claim SPI bus\n");
 		return ret;
 	}

 	if (command == CMD_PAGE_PROGRAM) {
 		/* send WREN */
 		ret = spi_flash_cmd_write_enable(flash);
 		if (ret < 0) {
 			debug("SF: Enabling Write failed\n");
 			goto releasebus;
 		}
 	}

 	/* do the transaction */
 	if (command == CMD_PAGE_PROGRAM)
 		ret = spi_flash_cmd_write(flash->spi, cmd, cmd_len, buf, len);
 	else
 		ret = spi_flash_cmd_read(flash->spi, cmd, cmd_len, buf, len);
 	if (ret < 0)
 		debug("SF: Transaction failed\n");

 releasebus:
 	/* release the bus */
 	spi_release_bus(flash->spi);
 	return ret;
 }

 static int ramtron_read(struct spi_flash *flash,
 		u32 offset, size_t len, void *buf)
 {
 	return ramtron_common(flash, offset, len, buf,
 		CMD_READ_ARRAY_SLOW);
 }

 static int ramtron_write(struct spi_flash *flash,
 		u32 offset, size_t len, const void *buf)
 {
 	return ramtron_common(flash, offset, len, (void *)buf,
 		CMD_PAGE_PROGRAM);
 }

 static int ramtron_erase(struct spi_flash *flash, u32 offset, size_t len)
 {
 	debug("SF: Erase of RAMTRON FRAMs is pointless\n");
 	return -1;
 }

 /*
  * nore: we are called here with idcode pointing to the first non-0x7f byte
  * already!
  */
 struct spi_flash *spi_fram_probe_ramtron(struct spi_slave *spi, u8 *idcode)
 {
 	const struct ramtron_spi_fram_params *params;
 	struct ramtron_spi_fram *sn;
 	unsigned int i;
 #ifdef CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC
 	int ret;
 	u8 sr;
 #endif

 	/* NOTE: the bus has been claimed before this function is called! */
 	switch (idcode[0]) {
 	case 0xc2:
 		/* JEDEC conformant RAMTRON id */
 		for (i = 0; i < ARRAY_SIZE(ramtron_spi_fram_table); i++) {
 			params = &ramtron_spi_fram_table[i];
 			if (idcode[1] == params->id1 && idcode[2] == params->id2)
 				goto found;
 		}
 		break;
 #ifdef CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC
 	case 0xff:
 		/*
 		 * probably open MISO line, pulled up.
 		 * We COULD have a non JEDEC conformant FRAM here,
 		 * read the status register to verify
 		 */
 		ret = spi_flash_cmd(spi, CMD_READ_STATUS, &sr, 1);
 		if (ret)
 			return NULL;

 		/* Bits 5,4,0 are fixed 0 for all devices */
 		if ((sr & 0x31) != 0x00)
 			return NULL;
 		/* now find the device */
 		for (i = 0; i < ARRAY_SIZE(ramtron_spi_fram_table); i++) {
 			params = &ramtron_spi_fram_table[i];
 			if (!strcmp(params->name, CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC))
 				goto found;
 		}
 		debug("SF: Unsupported non-JEDEC RAMTRON device "
 			CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC "\n");
 		break;
 #endif
 	default:
 		break;
 	}

 	/* arriving here means no method has found a device we can handle */
 	debug("SF/ramtron: unsupported device id0=%02x id1=%02x id2=%02x\n",
 		idcode[0], idcode[1], idcode[2]);
 	return NULL;

 found:
 	sn = malloc(sizeof(*sn));
 	if (!sn) {
 		debug("SF: Failed to allocate memory\n");
 		return NULL;
 	}

 	sn->params = params;
 	sn->flash.spi = spi;
 	sn->flash.name = params->name;

 	sn->flash.write = ramtron_write;
 	sn->flash.read = ramtron_read;
 	sn->flash.erase = ramtron_erase;
 	sn->flash.size = params->size;

 	return &sn->flash;
 }
	/*
	* (C) Copyright 2010
	* Reinhard Meyer, EMK Elektronik, reinhard.meyer@emk-elektronik.de
	*
	* See file CREDITS for list of people who contributed to this
	* project.
	*
	* 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.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
	* MA 02111-1307 USA
	*/

	/*
	* Note: RAMTRON SPI FRAMs are ferroelectric, nonvolatile RAMs
	* with an interface identical to SPI flash devices.
	* However since they behave like RAM there are no delays or
	* busy polls required. They can sustain read or write at the
	* allowed SPI bus speed, which can be 40 MHz for some devices.
	*
	* Unfortunately some RAMTRON devices do not have a means of
	* identifying them. They will leave the SO line undriven when
	* the READ-ID command is issued. It is therefore mandatory
	* that the MISO line has a proper pull-up, so that READ-ID
	* will return a row of 0xff. This 0xff pseudo-id will cause
	* probes by all vendor specific functions that are designed
	* to handle it. If the MISO line is not pulled up, READ-ID
	* could return any random noise, even mimicking another
	* device.
	*
	* We use CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC
	* to define which device will be assumed after a simple status
	* register verify. This method is prone to false positive
	* detection and should therefore be the last to be tried.
	* Enter it in the last position in the table in spi_flash.c!
	*
	* The define CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC both activates
	* compilation of the special handler and defines the device
	* to assume.
	*/

	#include <common.h>
	#include <malloc.h>
	#include <spi_flash.h>
	#include "spi_flash_internal.h"

	/*
	* Properties of supported FRAMs
	* Note: speed is currently not used because we have no method to deliver that
	* value to the upper layers
	*/
	struct ramtron_spi_fram_params {
	u32 size; /* size in bytes */
	u8 addr_len; /* number of address bytes */
	u8 merge_cmd; /* some address bits are in the command byte */
	u8 id1; /* device ID 1 (family, density) */
	u8 id2; /* device ID 2 (sub, rev, rsvd) */
	u32 speed; /* max. SPI clock in Hz */
	const char name; / name for display and/or matching */
	};

	struct ramtron_spi_fram {
	struct spi_flash flash;
	const struct ramtron_spi_fram_params *params;
	};

	static inline struct ramtron_spi_fram *to_ramtron_spi_fram(struct spi_flash
	*flash)
	{
	return container_of(flash, struct ramtron_spi_fram, flash);
	}

	/*
	* table describing supported FRAM chips:
	* chips without RDID command must have the values 0xff for id1 and id2
	*/
	static const struct ramtron_spi_fram_params ramtron_spi_fram_table[] = {
	{
	.size = 32*1024,
	.addr_len = 2,
	.merge_cmd = 0,
	.id1 = 0x22,
	.id2 = 0x00,
	.speed = 40000000,
	.name = "FM25V02",
	},
	{
	.size = 32*1024,
	.addr_len = 2,
	.merge_cmd = 0,
	.id1 = 0x22,
	.id2 = 0x01,
	.speed = 40000000,
	.name = "FM25VN02",
	},
	{
	.size = 64*1024,
	.addr_len = 2,
	.merge_cmd = 0,
	.id1 = 0x23,
	.id2 = 0x00,
	.speed = 40000000,
	.name = "FM25V05",
	},
	{
	.size = 64*1024,
	.addr_len = 2,
	.merge_cmd = 0,
	.id1 = 0x23,
	.id2 = 0x01,
	.speed = 40000000,
	.name = "FM25VN05",
	},
	{
	.size = 128*1024,
	.addr_len = 3,
	.merge_cmd = 0,
	.id1 = 0x24,
	.id2 = 0x00,
	.speed = 40000000,
	.name = "FM25V10",
	},
	{
	.size = 128*1024,
	.addr_len = 3,
	.merge_cmd = 0,
	.id1 = 0x24,
	.id2 = 0x01,
	.speed = 40000000,
	.name = "FM25VN10",
	},
	#ifdef CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC
	{
	.size = 256*1024,
	.addr_len = 3,
	.merge_cmd = 0,
	.id1 = 0xff,
	.id2 = 0xff,
	.speed = 40000000,
	.name = "FM25H20",
	},
	#endif
	};

	static int ramtron_common(struct spi_flash *flash,
	u32 offset, size_t len, void *buf, u8 command)
	{
	struct ramtron_spi_fram *sn = to_ramtron_spi_fram(flash);
	u8 cmd[4];
	int cmd_len;
	int ret;

	if (sn->params->addr_len == 3 && sn->params->merge_cmd == 0) {
	cmd[0] = command;
	cmd[1] = offset >> 16;
	cmd[2] = offset >> 8;
	cmd[3] = offset;
	cmd_len = 4;
	} else if (sn->params->addr_len == 2 && sn->params->merge_cmd == 0) {
	cmd[0] = command;
	cmd[1] = offset >> 8;
	cmd[2] = offset;
	cmd_len = 3;
	} else {
	printf("SF: unsupported addr_len or merge_cmd\n");
	return -1;
	}

	/* claim the bus */
	ret = spi_claim_bus(flash->spi);
	if (ret) {
	debug("SF: Unable to claim SPI bus\n");
	return ret;
	}

	if (command == CMD_PAGE_PROGRAM) {
	/* send WREN */
	ret = spi_flash_cmd_write_enable(flash);
	if (ret < 0) {
	debug("SF: Enabling Write failed\n");
	goto releasebus;
	}
	}

	/* do the transaction */
	if (command == CMD_PAGE_PROGRAM)
	ret = spi_flash_cmd_write(flash->spi, cmd, cmd_len, buf, len);
	else
	ret = spi_flash_cmd_read(flash->spi, cmd, cmd_len, buf, len);
	if (ret < 0)
	debug("SF: Transaction failed\n");

	releasebus:
	/* release the bus */
	spi_release_bus(flash->spi);
	return ret;
	}

	static int ramtron_read(struct spi_flash *flash,
	u32 offset, size_t len, void *buf)
	{
	return ramtron_common(flash, offset, len, buf,
	CMD_READ_ARRAY_SLOW);
	}

	static int ramtron_write(struct spi_flash *flash,
	u32 offset, size_t len, const void *buf)
	{
	return ramtron_common(flash, offset, len, (void *)buf,
	CMD_PAGE_PROGRAM);
	}

	static int ramtron_erase(struct spi_flash *flash, u32 offset, size_t len)
	{
	debug("SF: Erase of RAMTRON FRAMs is pointless\n");
	return -1;
	}

	/*
	* nore: we are called here with idcode pointing to the first non-0x7f byte
	* already!
	*/
	struct spi_flash spi_fram_probe_ramtron(struct spi_slave spi, u8 *idcode)
	{
	const struct ramtron_spi_fram_params *params;
	struct ramtron_spi_fram *sn;
	unsigned int i;
	#ifdef CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC
	int ret;
	u8 sr;
	#endif

	/* NOTE: the bus has been claimed before this function is called! */
	switch (idcode[0]) {
	case 0xc2:
	/* JEDEC conformant RAMTRON id */
	for (i = 0; i < ARRAY_SIZE(ramtron_spi_fram_table); i++) {
	params = &ramtron_spi_fram_table[i];
	if (idcode[1] == params->id1 && idcode[2] == params->id2)
	goto found;
	}
	break;
	#ifdef CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC
	case 0xff:
	/*
	* probably open MISO line, pulled up.
	* We COULD have a non JEDEC conformant FRAM here,
	* read the status register to verify
	*/
	ret = spi_flash_cmd(spi, CMD_READ_STATUS, &sr, 1);
	if (ret)
	return NULL;

	/* Bits 5,4,0 are fixed 0 for all devices */
	if ((sr & 0x31) != 0x00)
	return NULL;
	/* now find the device */
	for (i = 0; i < ARRAY_SIZE(ramtron_spi_fram_table); i++) {
	params = &ramtron_spi_fram_table[i];
	if (!strcmp(params->name, CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC))
	goto found;
	}
	debug("SF: Unsupported non-JEDEC RAMTRON device "
	CONFIG_SPI_FRAM_RAMTRON_NON_JEDEC "\n");
	break;
	#endif
	default:
	break;
	}

	/* arriving here means no method has found a device we can handle */
	debug("SF/ramtron: unsupported device id0=%02x id1=%02x id2=%02x\n",
	idcode[0], idcode[1], idcode[2]);
	return NULL;

	found:
	sn = malloc(sizeof(*sn));
	if (!sn) {
	debug("SF: Failed to allocate memory\n");
	return NULL;
	}

	sn->params = params;
	sn->flash.spi = spi;
	sn->flash.name = params->name;

	sn->flash.write = ramtron_write;
	sn->flash.read = ramtron_read;
	sn->flash.erase = ramtron_erase;
	sn->flash.size = params->size;

	return &sn->flash;
	}