Commit 3371d663 authored by Marc Gonzalez's avatar Marc Gonzalez Committed by Boris Brezillon
Browse files

mtd: nand: Support controllers with custom page 



If your controller already sends the required NAND commands when
reading or writing a page, then the framework is not supposed to
send READ0 and SEQIN/PAGEPROG respectively.

Signed-off-by: default avatarMarc Gonzalez <marc_gonzalez@sigmadesigns.com>
Signed-off-by: default avatarBoris Brezillon <boris.brezillon@free-electrons.com>
parent fc80f21a

drivers/mtd/nand/nand_base.c

+31 −3
Original line number Diff line number Diff line
@@ -1961,6 +1961,7 @@ static int nand_do_read_ops(struct mtd_info *mtd, loff_t from, 
						 __func__, buf);



read_retry:

			if (nand_standard_page_accessors(&chip->ecc))

				chip->cmdfunc(mtd, NAND_CMD_READ0, 0x00, page);



			/*
@@ -2649,6 +2650,7 @@ static int nand_write_page(struct mtd_info *mtd, struct nand_chip *chip, 
	else

		subpage = 0;



	if (nand_standard_page_accessors(&chip->ecc))

		chip->cmdfunc(mtd, NAND_CMD_SEQIN, 0x00, page);



	if (unlikely(raw))
@@ -2672,6 +2674,7 @@ static int nand_write_page(struct mtd_info *mtd, struct nand_chip *chip, 


	if (!cached || !NAND_HAS_CACHEPROG(chip)) {



		if (nand_standard_page_accessors(&chip->ecc))

			chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);

		status = chip->waitfunc(mtd, chip);

		/*
@@ -4511,6 +4514,26 @@ static bool nand_ecc_strength_good(struct mtd_info *mtd) 
	return corr >= ds_corr && ecc->strength >= chip->ecc_strength_ds;

}



static bool invalid_ecc_page_accessors(struct nand_chip *chip)

{

	struct nand_ecc_ctrl *ecc = &chip->ecc;



	if (nand_standard_page_accessors(ecc))

		return false;



	/*

	 * NAND_ECC_CUSTOM_PAGE_ACCESS flag is set, make sure the NAND

	 * controller driver implements all the page accessors because

	 * default helpers are not suitable when the core does not

	 * send the READ0/PAGEPROG commands.

	 */

	return (!ecc->read_page || !ecc->write_page ||

		!ecc->read_page_raw || !ecc->write_page_raw ||

		(NAND_HAS_SUBPAGE_READ(chip) && !ecc->read_subpage) ||

		(NAND_HAS_SUBPAGE_WRITE(chip) && !ecc->write_subpage &&

		 ecc->hwctl && ecc->calculate));

}



/**

 * nand_scan_tail - [NAND Interface] Scan for the NAND device

 * @mtd: MTD device structure
@@ -4531,6 +4554,11 @@ int nand_scan_tail(struct mtd_info *mtd) 
		   !(chip->bbt_options & NAND_BBT_USE_FLASH)))

		return -EINVAL;



	if (invalid_ecc_page_accessors(chip)) {

		pr_err("Invalid ECC page accessors setup\n");

		return -EINVAL;

	}



	if (!(chip->options & NAND_OWN_BUFFERS)) {

		nbuf = kzalloc(sizeof(*nbuf) + mtd->writesize

				+ mtd->oobsize * 3, GFP_KERNEL);

include/linux/mtd/nand.h

+12 −0
Original line number Diff line number Diff line
@@ -142,6 +142,12 @@ enum nand_ecc_algo { 
 */

#define NAND_ECC_GENERIC_ERASED_CHECK	BIT(0)

#define NAND_ECC_MAXIMIZE		BIT(1)

/*

 * If your controller already sends the required NAND commands when

 * reading or writing a page, then the framework is not supposed to

 * send READ0 and SEQIN/PAGEPROG respectively.

 */

#define NAND_ECC_CUSTOM_PAGE_ACCESS	BIT(2)



/* Bit mask for flags passed to do_nand_read_ecc */

#define NAND_GET_DEVICE		0x80
@@ -186,6 +192,7 @@ enum nand_ecc_algo { 
/* Macros to identify the above */

#define NAND_HAS_CACHEPROG(chip) ((chip->options & NAND_CACHEPRG))

#define NAND_HAS_SUBPAGE_READ(chip) ((chip->options & NAND_SUBPAGE_READ))

#define NAND_HAS_SUBPAGE_WRITE(chip) !((chip)->options & NAND_NO_SUBPAGE_WRITE)



/* Non chip related options */

/* This option skips the bbt scan during initialization. */
@@ -568,6 +575,11 @@ struct nand_ecc_ctrl { 
			int page);

};



static inline int nand_standard_page_accessors(struct nand_ecc_ctrl *ecc)

{

	return !(ecc->options & NAND_ECC_CUSTOM_PAGE_ACCESS);

}



/**

 * struct nand_buffers - buffer structure for read/write

 * @ecccalc:	buffer pointer for calculated ECC, size is oobsize.