Commit 6fb277ba authored by Florian Fainelli's avatar Florian Fainelli Committed by David Woodhouse
Browse files

mtd: nand: split ONFI detection logic to its own function 



In order to reduce the indentation and improve the readability of nand_get_
flash_type, split the ONFI detection logic to its own function. The detection
logic inside nand_flash_detect_onfi is also rewritten to allow for less
indentation.

Signed-off-by: default avatarFlorian Fainelli <ffainelli@freebox.fr>
Signed-off-by: default avatarArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: default avatarDavid Woodhouse <David.Woodhouse@intel.com>
parent d1e1f4e4

drivers/mtd/nand/nand_base.c

+71 −61
Original line number Diff line number Diff line
@@ -2818,6 +2818,72 @@ static u16 onfi_crc16(u16 crc, u8 const *p, size_t len) 
	return crc;

}



/*

 * Check if the NAND chip is ONFI compliant, returns 1 if it is, 0 otherwise

 */

static int nand_flash_detect_onfi(struct mtd_info *mtd, struct nand_chip *chip,

					int busw)

{

	struct nand_onfi_params *p = &chip->onfi_params;

	int i;

	int val;



	/* try ONFI for unknow chip or LP */

	chip->cmdfunc(mtd, NAND_CMD_READID, 0x20, -1);

	if (chip->read_byte(mtd) != 'O' || chip->read_byte(mtd) != 'N' ||

		chip->read_byte(mtd) != 'F' || chip->read_byte(mtd) != 'I')

		return 0;



	printk(KERN_INFO "ONFI flash detected\n");

	chip->cmdfunc(mtd, NAND_CMD_PARAM, 0, -1);

	for (i = 0; i < 3; i++) {

		chip->read_buf(mtd, (uint8_t *)p, sizeof(*p));

		if (onfi_crc16(ONFI_CRC_BASE, (uint8_t *)p, 254) ==

				le16_to_cpu(p->crc)) {

			printk(KERN_INFO "ONFI param page %d valid\n", i);

			break;

		}

	}



	if (i == 3)

		return 0;



	/* check version */

	val = le16_to_cpu(p->revision);

	if (val == 1 || val > (1 << 4)) {

		printk(KERN_INFO "%s: unsupported ONFI version: %d\n",

								__func__, val);

		return 0;

	}



	if (val & (1 << 4))

		chip->onfi_version = 22;

	else if (val & (1 << 3))

		chip->onfi_version = 21;

	else if (val & (1 << 2))

		chip->onfi_version = 20;

	else

		chip->onfi_version = 10;



	sanitize_string(p->manufacturer, sizeof(p->manufacturer));

	sanitize_string(p->model, sizeof(p->model));

	if (!mtd->name)

		mtd->name = p->model;

	mtd->writesize = le32_to_cpu(p->byte_per_page);

	mtd->erasesize = le32_to_cpu(p->pages_per_block) * mtd->writesize;

	mtd->oobsize = le16_to_cpu(p->spare_bytes_per_page);

	chip->chipsize = le32_to_cpu(p->blocks_per_lun) * mtd->erasesize;

	busw = 0;

	if (le16_to_cpu(p->features) & 1)

		busw = NAND_BUSWIDTH_16;



	chip->options &= ~NAND_CHIPOPTIONS_MSK;

	chip->options |= (NAND_NO_READRDY |

			NAND_NO_AUTOINCR) & NAND_CHIPOPTIONS_MSK;



	return 1;

}



/*

 * Get the flash and manufacturer id and lookup if the type is supported

 */
@@ -2828,6 +2894,7 @@ static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd, 
{

	int i, maf_idx;

	u8 id_data[8];

	int ret;



	/* Select the device */

	chip->select_chip(mtd, 0);
@@ -2872,67 +2939,10 @@ static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd, 


	chip->onfi_version = 0;

	if (!type->name || !type->pagesize) {

		/* try ONFI for unknow chip or LP */

		chip->cmdfunc(mtd, NAND_CMD_READID, 0x20, -1);

		if (chip->read_byte(mtd) == 'O' &&

			chip->read_byte(mtd) == 'N' &&

			chip->read_byte(mtd) == 'F' &&

			chip->read_byte(mtd) == 'I') {



			struct nand_onfi_params *p = &chip->onfi_params;

			int i;



			printk(KERN_INFO "ONFI flash detected\n");

			chip->cmdfunc(mtd, NAND_CMD_PARAM, 0, -1);

			for (i = 0; i < 3; i++) {

				chip->read_buf(mtd, (uint8_t *)p, sizeof(*p));

				if (onfi_crc16(ONFI_CRC_BASE, (uint8_t *)p, 254) ==

								le16_to_cpu(p->crc))

				{

					 printk(KERN_INFO "ONFI param page %d valid\n", i);

					 break;

				}

			}



			if (i < 3) {

				/* check version */

				int val = le16_to_cpu(p->revision);

				if (val == 1 || val > (1 << 4))

					printk(KERN_INFO "%s: unsupported ONFI version: %d\n",

						__func__, val);

				else {

					if (val & (1 << 4))

						chip->onfi_version = 22;

					else if (val & (1 << 3))

						chip->onfi_version = 21;

					else if (val & (1 << 2))

						chip->onfi_version = 20;

					else

						chip->onfi_version = 10;

				}

			}



			if (chip->onfi_version) {

				sanitize_string(p->manufacturer, sizeof(p->manufacturer));

				sanitize_string(p->model, sizeof(p->model));

				if (!mtd->name)

					mtd->name = p->model;

				mtd->writesize = le32_to_cpu(p->byte_per_page);

				mtd->erasesize = le32_to_cpu(p->pages_per_block)*mtd->writesize;

				mtd->oobsize = le16_to_cpu(p->spare_bytes_per_page);

				chip->chipsize = le32_to_cpu(p->blocks_per_lun) * mtd->erasesize;

				busw = 0;

				if (le16_to_cpu(p->features) & 1)

					busw = NAND_BUSWIDTH_16;



				chip->options &= ~NAND_CHIPOPTIONS_MSK;

				chip->options |= (NAND_NO_READRDY |

						NAND_NO_AUTOINCR) & NAND_CHIPOPTIONS_MSK;



		/* Check is chip is ONFI compliant */

		ret = nand_flash_detect_onfi(mtd, chip, busw);

		if (ret)

			goto ident_done;



			}

		}

	}



	chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);

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