drivers/mtd/devices/bcm47xxsflash.c - kernel/msm-4.9 - Gitiles

 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/delay.h>
 #include <linux/ioport.h>
 #include <linux/mtd/mtd.h>
 #include <linux/platform_device.h>
 #include <linux/bcma/bcma.h>

 #include "bcm47xxsflash.h"

 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("Serial flash driver for BCMA bus");

 static const char * const probes[] = { "bcm47xxpart", NULL };

 /**************************************************
  * Various helpers
  **************************************************/

 static void bcm47xxsflash_cmd(struct bcm47xxsflash *b47s, u32 opcode)
 {
 	int i;

 	b47s->cc_write(b47s, BCMA_CC_FLASHCTL, BCMA_CC_FLASHCTL_START | opcode);
 	for (i = 0; i < 1000; i++) {
 		if (!(b47s->cc_read(b47s, BCMA_CC_FLASHCTL) &
 		      BCMA_CC_FLASHCTL_BUSY))
 			return;
 		cpu_relax();
 	}
 	pr_err("Control command failed (timeout)!\n");
 }

 static int bcm47xxsflash_poll(struct bcm47xxsflash *b47s, int timeout)
 {
 	unsigned long deadline = jiffies + timeout;

 	do {
 		switch (b47s->type) {
 		case BCM47XXSFLASH_TYPE_ST:
 			bcm47xxsflash_cmd(b47s, OPCODE_ST_RDSR);
 			if (!(b47s->cc_read(b47s, BCMA_CC_FLASHDATA) &
 			      SR_ST_WIP))
 				return 0;
 			break;
 		case BCM47XXSFLASH_TYPE_ATMEL:
 			bcm47xxsflash_cmd(b47s, OPCODE_AT_STATUS);
 			if (b47s->cc_read(b47s, BCMA_CC_FLASHDATA) &
 			    SR_AT_READY)
 				return 0;
 			break;
 		}

 		cpu_relax();
 		udelay(1);
 	} while (!time_after_eq(jiffies, deadline));

 	pr_err("Timeout waiting for flash to be ready!\n");

 	return -EBUSY;
 }

 /**************************************************
  * MTD ops
  **************************************************/

 static int bcm47xxsflash_erase(struct mtd_info *mtd, struct erase_info *erase)
 {
 	struct bcm47xxsflash *b47s = mtd->priv;
 	int err;

 	switch (b47s->type) {
 	case BCM47XXSFLASH_TYPE_ST:
 		bcm47xxsflash_cmd(b47s, OPCODE_ST_WREN);
 		b47s->cc_write(b47s, BCMA_CC_FLASHADDR, erase->addr);
 		/* Newer flashes have "sub-sectors" which can be erased
 		 * independently with a new command: ST_SSE. The ST_SE command
 		 * erases 64KB just as before.
 		 */
 		if (b47s->blocksize < (64 * 1024))
 			bcm47xxsflash_cmd(b47s, OPCODE_ST_SSE);
 		else
 			bcm47xxsflash_cmd(b47s, OPCODE_ST_SE);
 		break;
 	case BCM47XXSFLASH_TYPE_ATMEL:
 		b47s->cc_write(b47s, BCMA_CC_FLASHADDR, erase->addr << 1);
 		bcm47xxsflash_cmd(b47s, OPCODE_AT_PAGE_ERASE);
 		break;
 	}

 	err = bcm47xxsflash_poll(b47s, HZ);
 	if (err)
 		erase->state = MTD_ERASE_FAILED;
 	else
 		erase->state = MTD_ERASE_DONE;

 	if (erase->callback)
 		erase->callback(erase);

 	return err;
 }

 static int bcm47xxsflash_read(struct mtd_info *mtd, loff_t from, size_t len,
 			      size_t *retlen, u_char *buf)
 {
 	struct bcm47xxsflash *b47s = mtd->priv;

 	/* Check address range */
 	if ((from + len) > mtd->size)
 		return -EINVAL;

 	memcpy_fromio(buf, b47s->window + from, len);
 	*retlen = len;

 	return len;
 }

 static int bcm47xxsflash_write_st(struct mtd_info *mtd, u32 offset, size_t len,
 				  const u_char *buf)
 {
 	struct bcm47xxsflash *b47s = mtd->priv;
 	int written = 0;

 	/* Enable writes */
 	bcm47xxsflash_cmd(b47s, OPCODE_ST_WREN);

 	/* Write first byte */
 	b47s->cc_write(b47s, BCMA_CC_FLASHADDR, offset);
 	b47s->cc_write(b47s, BCMA_CC_FLASHDATA, *buf++);

 	/* Program page */
 	if (b47s->bcma_cc->core->id.rev < 20) {
 		bcm47xxsflash_cmd(b47s, OPCODE_ST_PP);
 		return 1; /* 1B written */
 	}

 	/* Program page and set CSA (on newer chips we can continue writing) */
 	bcm47xxsflash_cmd(b47s, OPCODE_ST_CSA | OPCODE_ST_PP);
 	offset++;
 	len--;
 	written++;

 	while (len > 0) {
 		/* Page boundary, another function call is needed */
 		if ((offset & 0xFF) == 0)
 			break;

 		bcm47xxsflash_cmd(b47s, OPCODE_ST_CSA | *buf++);
 		offset++;
 		len--;
 		written++;
 	}

 	/* All done, drop CSA & poll */
 	b47s->cc_write(b47s, BCMA_CC_FLASHCTL, 0);
 	udelay(1);
 	if (bcm47xxsflash_poll(b47s, HZ / 10))
 		pr_err("Flash rejected dropping CSA\n");

 	return written;
 }

 static int bcm47xxsflash_write_at(struct mtd_info *mtd, u32 offset, size_t len,
 				  const u_char *buf)
 {
 	struct bcm47xxsflash *b47s = mtd->priv;
 	u32 mask = b47s->blocksize - 1;
 	u32 page = (offset & ~mask) << 1;
 	u32 byte = offset & mask;
 	int written = 0;

 	/* If we don't overwrite whole page, read it to the buffer first */
 	if (byte || (len < b47s->blocksize)) {
 		int err;

 		b47s->cc_write(b47s, BCMA_CC_FLASHADDR, page);
 		bcm47xxsflash_cmd(b47s, OPCODE_AT_BUF1_LOAD);
 		/* 250 us for AT45DB321B */
 		err = bcm47xxsflash_poll(b47s, HZ / 1000);
 		if (err) {
 			pr_err("Timeout reading page 0x%X info buffer\n", page);
 			return err;
 		}
 	}

 	/* Change buffer content with our data */
 	while (len > 0) {
 		/* Page boundary, another function call is needed */
 		if (byte == b47s->blocksize)
 			break;

 		b47s->cc_write(b47s, BCMA_CC_FLASHADDR, byte++);
 		b47s->cc_write(b47s, BCMA_CC_FLASHDATA, *buf++);
 		bcm47xxsflash_cmd(b47s, OPCODE_AT_BUF1_WRITE);
 		len--;
 		written++;
 	}

 	/* Program page with the buffer content */
 	b47s->cc_write(b47s, BCMA_CC_FLASHADDR, page);
 	bcm47xxsflash_cmd(b47s, OPCODE_AT_BUF1_PROGRAM);

 	return written;
 }

 static int bcm47xxsflash_write(struct mtd_info *mtd, loff_t to, size_t len,
 			       size_t *retlen, const u_char *buf)
 {
 	struct bcm47xxsflash *b47s = mtd->priv;
 	int written;

 	/* Writing functions can return without writing all passed data, for
 	 * example when the hardware is too old or when we git page boundary.
 	 */
 	while (len > 0) {
 		switch (b47s->type) {
 		case BCM47XXSFLASH_TYPE_ST:
 			written = bcm47xxsflash_write_st(mtd, to, len, buf);
 			break;
 		case BCM47XXSFLASH_TYPE_ATMEL:
 			written = bcm47xxsflash_write_at(mtd, to, len, buf);
 			break;
 		default:
 			BUG_ON(1);
 		}
 		if (written < 0) {
 			pr_err("Error writing at offset 0x%llX\n", to);
 			return written;
 		}
 		to += (loff_t)written;
 		len -= written;
 		*retlen += written;
 		buf += written;
 	}

 	return 0;
 }

 static void bcm47xxsflash_fill_mtd(struct bcm47xxsflash *b47s,
 				   struct device *dev)
 {
 	struct mtd_info *mtd = &b47s->mtd;

 	mtd->priv = b47s;
 	mtd->dev.parent = dev;
 	mtd->name = "bcm47xxsflash";

 	mtd->type = MTD_NORFLASH;
 	mtd->flags = MTD_CAP_NORFLASH;
 	mtd->size = b47s->size;
 	mtd->erasesize = b47s->blocksize;
 	mtd->writesize = 1;
 	mtd->writebufsize = 1;

 	mtd->_erase = bcm47xxsflash_erase;
 	mtd->_read = bcm47xxsflash_read;
 	mtd->_write = bcm47xxsflash_write;
 }

 /**************************************************
  * BCMA
  **************************************************/

 static int bcm47xxsflash_bcma_cc_read(struct bcm47xxsflash *b47s, u16 offset)
 {
 	return bcma_cc_read32(b47s->bcma_cc, offset);
 }

 static void bcm47xxsflash_bcma_cc_write(struct bcm47xxsflash *b47s, u16 offset,
 					u32 value)
 {
 	bcma_cc_write32(b47s->bcma_cc, offset, value);
 }

 static int bcm47xxsflash_bcma_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct bcma_sflash *sflash = dev_get_platdata(dev);
 	struct bcm47xxsflash *b47s;
 	struct resource *res;
 	int err;

 	b47s = devm_kzalloc(dev, sizeof(*b47s), GFP_KERNEL);
 	if (!b47s)
 		return -ENOMEM;
 	sflash->priv = b47s;

 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!res) {
 		dev_err(dev, "invalid resource\n");
 		return -EINVAL;
 	}
 	if (!devm_request_mem_region(dev, res->start, resource_size(res),
 				     res->name)) {
 		dev_err(dev, "can't request region for resource %pR\n", res);
 		return -EBUSY;
 	}
 	b47s->window = ioremap_cache(res->start, resource_size(res));
 	if (!b47s->window) {
 		dev_err(dev, "ioremap failed for resource %pR\n", res);
 		return -ENOMEM;
 	}

 	b47s->bcma_cc = container_of(sflash, struct bcma_drv_cc, sflash);
 	b47s->cc_read = bcm47xxsflash_bcma_cc_read;
 	b47s->cc_write = bcm47xxsflash_bcma_cc_write;

 	switch (b47s->bcma_cc->capabilities & BCMA_CC_CAP_FLASHT) {
 	case BCMA_CC_FLASHT_STSER:
 		b47s->type = BCM47XXSFLASH_TYPE_ST;
 		break;
 	case BCMA_CC_FLASHT_ATSER:
 		b47s->type = BCM47XXSFLASH_TYPE_ATMEL;
 		break;
 	}

 	b47s->blocksize = sflash->blocksize;
 	b47s->numblocks = sflash->numblocks;
 	b47s->size = sflash->size;
 	bcm47xxsflash_fill_mtd(b47s, &pdev->dev);

 	err = mtd_device_parse_register(&b47s->mtd, probes, NULL, NULL, 0);
 	if (err) {
 		pr_err("Failed to register MTD device: %d\n", err);
 		iounmap(b47s->window);
 		return err;
 	}

 	if (bcm47xxsflash_poll(b47s, HZ / 10))
 		pr_warn("Serial flash busy\n");

 	return 0;
 }

 static int bcm47xxsflash_bcma_remove(struct platform_device *pdev)
 {
 	struct bcma_sflash *sflash = dev_get_platdata(&pdev->dev);
 	struct bcm47xxsflash *b47s = sflash->priv;

 	mtd_device_unregister(&b47s->mtd);
 	iounmap(b47s->window);

 	return 0;
 }

 static struct platform_driver bcma_sflash_driver = {
 	.probe	= bcm47xxsflash_bcma_probe,
 	.remove = bcm47xxsflash_bcma_remove,
 	.driver = {
 		.name = "bcma_sflash",
 	},
 };

 /**************************************************
  * Init
  **************************************************/

 module_platform_driver(bcma_sflash_driver);
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/slab.h>
	#include <linux/delay.h>
	#include <linux/ioport.h>
	#include <linux/mtd/mtd.h>
	#include <linux/platform_device.h>
	#include <linux/bcma/bcma.h>

	#include "bcm47xxsflash.h"

	MODULE_LICENSE("GPL");
	MODULE_DESCRIPTION("Serial flash driver for BCMA bus");

	static const char * const probes[] = { "bcm47xxpart", NULL };

	/**************************************************
	* Various helpers
	**************************************************/

	static void bcm47xxsflash_cmd(struct bcm47xxsflash *b47s, u32 opcode)
	{
	int i;

	b47s->cc_write(b47s, BCMA_CC_FLASHCTL, BCMA_CC_FLASHCTL_START \| opcode);
	for (i = 0; i < 1000; i++) {
	if (!(b47s->cc_read(b47s, BCMA_CC_FLASHCTL) &
	BCMA_CC_FLASHCTL_BUSY))
	return;
	cpu_relax();
	}
	pr_err("Control command failed (timeout)!\n");
	}

	static int bcm47xxsflash_poll(struct bcm47xxsflash *b47s, int timeout)
	{
	unsigned long deadline = jiffies + timeout;

	do {
	switch (b47s->type) {
	case BCM47XXSFLASH_TYPE_ST:
	bcm47xxsflash_cmd(b47s, OPCODE_ST_RDSR);
	if (!(b47s->cc_read(b47s, BCMA_CC_FLASHDATA) &
	SR_ST_WIP))
	return 0;
	break;
	case BCM47XXSFLASH_TYPE_ATMEL:
	bcm47xxsflash_cmd(b47s, OPCODE_AT_STATUS);
	if (b47s->cc_read(b47s, BCMA_CC_FLASHDATA) &
	SR_AT_READY)
	return 0;
	break;
	}

	cpu_relax();
	udelay(1);
	} while (!time_after_eq(jiffies, deadline));

	pr_err("Timeout waiting for flash to be ready!\n");

	return -EBUSY;
	}

	/**************************************************
	* MTD ops
	**************************************************/

	static int bcm47xxsflash_erase(struct mtd_info mtd, struct erase_info erase)
	{
	struct bcm47xxsflash *b47s = mtd->priv;
	int err;

	switch (b47s->type) {
	case BCM47XXSFLASH_TYPE_ST:
	bcm47xxsflash_cmd(b47s, OPCODE_ST_WREN);
	b47s->cc_write(b47s, BCMA_CC_FLASHADDR, erase->addr);
	/* Newer flashes have "sub-sectors" which can be erased
	* independently with a new command: ST_SSE. The ST_SE command
	* erases 64KB just as before.
	*/
	if (b47s->blocksize < (64 * 1024))
	bcm47xxsflash_cmd(b47s, OPCODE_ST_SSE);
	else
	bcm47xxsflash_cmd(b47s, OPCODE_ST_SE);
	break;
	case BCM47XXSFLASH_TYPE_ATMEL:
	b47s->cc_write(b47s, BCMA_CC_FLASHADDR, erase->addr << 1);
	bcm47xxsflash_cmd(b47s, OPCODE_AT_PAGE_ERASE);
	break;
	}

	err = bcm47xxsflash_poll(b47s, HZ);
	if (err)
	erase->state = MTD_ERASE_FAILED;
	else
	erase->state = MTD_ERASE_DONE;

	if (erase->callback)
	erase->callback(erase);

	return err;
	}

	static int bcm47xxsflash_read(struct mtd_info *mtd, loff_t from, size_t len,
	size_t retlen, u_char buf)
	{
	struct bcm47xxsflash *b47s = mtd->priv;

	/* Check address range */
	if ((from + len) > mtd->size)
	return -EINVAL;

	memcpy_fromio(buf, b47s->window + from, len);
	*retlen = len;

	return len;
	}

	static int bcm47xxsflash_write_st(struct mtd_info *mtd, u32 offset, size_t len,
	const u_char *buf)
	{
	struct bcm47xxsflash *b47s = mtd->priv;
	int written = 0;

	/* Enable writes */
	bcm47xxsflash_cmd(b47s, OPCODE_ST_WREN);

	/* Write first byte */
	b47s->cc_write(b47s, BCMA_CC_FLASHADDR, offset);
	b47s->cc_write(b47s, BCMA_CC_FLASHDATA, *buf++);

	/* Program page */
	if (b47s->bcma_cc->core->id.rev < 20) {
	bcm47xxsflash_cmd(b47s, OPCODE_ST_PP);
	return 1; /* 1B written */
	}

	/* Program page and set CSA (on newer chips we can continue writing) */
	bcm47xxsflash_cmd(b47s, OPCODE_ST_CSA \| OPCODE_ST_PP);
	offset++;
	len--;
	written++;

	while (len > 0) {
	/* Page boundary, another function call is needed */
	if ((offset & 0xFF) == 0)
	break;

	bcm47xxsflash_cmd(b47s, OPCODE_ST_CSA \| *buf++);
	offset++;
	len--;
	written++;
	}

	/* All done, drop CSA & poll */
	b47s->cc_write(b47s, BCMA_CC_FLASHCTL, 0);
	udelay(1);
	if (bcm47xxsflash_poll(b47s, HZ / 10))
	pr_err("Flash rejected dropping CSA\n");

	return written;
	}

	static int bcm47xxsflash_write_at(struct mtd_info *mtd, u32 offset, size_t len,
	const u_char *buf)
	{
	struct bcm47xxsflash *b47s = mtd->priv;
	u32 mask = b47s->blocksize - 1;
	u32 page = (offset & ~mask) << 1;
	u32 byte = offset & mask;
	int written = 0;

	/* If we don't overwrite whole page, read it to the buffer first */
	if (byte \|\| (len < b47s->blocksize)) {
	int err;

	b47s->cc_write(b47s, BCMA_CC_FLASHADDR, page);
	bcm47xxsflash_cmd(b47s, OPCODE_AT_BUF1_LOAD);
	/* 250 us for AT45DB321B */
	err = bcm47xxsflash_poll(b47s, HZ / 1000);
	if (err) {
	pr_err("Timeout reading page 0x%X info buffer\n", page);
	return err;
	}
	}

	/* Change buffer content with our data */
	while (len > 0) {
	/* Page boundary, another function call is needed */
	if (byte == b47s->blocksize)
	break;

	b47s->cc_write(b47s, BCMA_CC_FLASHADDR, byte++);
	b47s->cc_write(b47s, BCMA_CC_FLASHDATA, *buf++);
	bcm47xxsflash_cmd(b47s, OPCODE_AT_BUF1_WRITE);
	len--;
	written++;
	}

	/* Program page with the buffer content */
	b47s->cc_write(b47s, BCMA_CC_FLASHADDR, page);
	bcm47xxsflash_cmd(b47s, OPCODE_AT_BUF1_PROGRAM);

	return written;
	}

	static int bcm47xxsflash_write(struct mtd_info *mtd, loff_t to, size_t len,
	size_t retlen, const u_char buf)
	{
	struct bcm47xxsflash *b47s = mtd->priv;
	int written;

	/* Writing functions can return without writing all passed data, for
	* example when the hardware is too old or when we git page boundary.
	*/
	while (len > 0) {
	switch (b47s->type) {
	case BCM47XXSFLASH_TYPE_ST:
	written = bcm47xxsflash_write_st(mtd, to, len, buf);
	break;
	case BCM47XXSFLASH_TYPE_ATMEL:
	written = bcm47xxsflash_write_at(mtd, to, len, buf);
	break;
	default:
	BUG_ON(1);
	}
	if (written < 0) {
	pr_err("Error writing at offset 0x%llX\n", to);
	return written;
	}
	to += (loff_t)written;
	len -= written;
	*retlen += written;
	buf += written;
	}

	return 0;
	}

	static void bcm47xxsflash_fill_mtd(struct bcm47xxsflash *b47s,
	struct device *dev)
	{
	struct mtd_info *mtd = &b47s->mtd;

	mtd->priv = b47s;
	mtd->dev.parent = dev;
	mtd->name = "bcm47xxsflash";

	mtd->type = MTD_NORFLASH;
	mtd->flags = MTD_CAP_NORFLASH;
	mtd->size = b47s->size;
	mtd->erasesize = b47s->blocksize;
	mtd->writesize = 1;
	mtd->writebufsize = 1;

	mtd->_erase = bcm47xxsflash_erase;
	mtd->_read = bcm47xxsflash_read;
	mtd->_write = bcm47xxsflash_write;
	}

	/**************************************************
	* BCMA
	**************************************************/

	static int bcm47xxsflash_bcma_cc_read(struct bcm47xxsflash *b47s, u16 offset)
	{
	return bcma_cc_read32(b47s->bcma_cc, offset);
	}

	static void bcm47xxsflash_bcma_cc_write(struct bcm47xxsflash *b47s, u16 offset,
	u32 value)
	{
	bcma_cc_write32(b47s->bcma_cc, offset, value);
	}

	static int bcm47xxsflash_bcma_probe(struct platform_device *pdev)
	{
	struct device *dev = &pdev->dev;
	struct bcma_sflash *sflash = dev_get_platdata(dev);
	struct bcm47xxsflash *b47s;
	struct resource *res;
	int err;

	b47s = devm_kzalloc(dev, sizeof(*b47s), GFP_KERNEL);
	if (!b47s)
	return -ENOMEM;
	sflash->priv = b47s;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res) {
	dev_err(dev, "invalid resource\n");
	return -EINVAL;
	}
	if (!devm_request_mem_region(dev, res->start, resource_size(res),
	res->name)) {
	dev_err(dev, "can't request region for resource %pR\n", res);
	return -EBUSY;
	}
	b47s->window = ioremap_cache(res->start, resource_size(res));
	if (!b47s->window) {
	dev_err(dev, "ioremap failed for resource %pR\n", res);
	return -ENOMEM;
	}

	b47s->bcma_cc = container_of(sflash, struct bcma_drv_cc, sflash);
	b47s->cc_read = bcm47xxsflash_bcma_cc_read;
	b47s->cc_write = bcm47xxsflash_bcma_cc_write;

	switch (b47s->bcma_cc->capabilities & BCMA_CC_CAP_FLASHT) {
	case BCMA_CC_FLASHT_STSER:
	b47s->type = BCM47XXSFLASH_TYPE_ST;
	break;
	case BCMA_CC_FLASHT_ATSER:
	b47s->type = BCM47XXSFLASH_TYPE_ATMEL;
	break;
	}

	b47s->blocksize = sflash->blocksize;
	b47s->numblocks = sflash->numblocks;
	b47s->size = sflash->size;
	bcm47xxsflash_fill_mtd(b47s, &pdev->dev);

	err = mtd_device_parse_register(&b47s->mtd, probes, NULL, NULL, 0);
	if (err) {
	pr_err("Failed to register MTD device: %d\n", err);
	iounmap(b47s->window);
	return err;
	}

	if (bcm47xxsflash_poll(b47s, HZ / 10))
	pr_warn("Serial flash busy\n");

	return 0;
	}

	static int bcm47xxsflash_bcma_remove(struct platform_device *pdev)
	{
	struct bcma_sflash *sflash = dev_get_platdata(&pdev->dev);
	struct bcm47xxsflash *b47s = sflash->priv;

	mtd_device_unregister(&b47s->mtd);
	iounmap(b47s->window);

	return 0;
	}

	static struct platform_driver bcma_sflash_driver = {
	.probe = bcm47xxsflash_bcma_probe,
	.remove = bcm47xxsflash_bcma_remove,
	.driver = {
	.name = "bcma_sflash",
	},
	};

	/**************************************************
	* Init
	**************************************************/

	module_platform_driver(bcma_sflash_driver);