Commit c66d0391 authored by Pekon Gupta's avatar Pekon Gupta Committed by Brian Norris
Browse files

mtd: nand: omap: combine different flavours of 1-bit hamming ecc schemes 



OMAP NAND driver currently supports multiple flavours of 1-bit Hamming
ecc-scheme, like:
- OMAP_ECC_HAMMING_CODE_DEFAULT
	1-bit hamming ecc code using software library
- OMAP_ECC_HAMMING_CODE_HW
	1-bit hamming ecc-code using GPMC h/w engine
- OMAP_ECC_HAMMING_CODE_HW_ROMCODE
	1-bit hamming ecc-code using GPMC h/w engin with ecc-layout compatible
	to ROM code.

This patch combines above multiple ecc-schemes into single implementation:
- OMAP_ECC_HAM1_CODE_HW
	1-bit hamming ecc-code using GPMC h/w engine with ROM-code compatible
	ecc-layout.

Signed-off-by: default avatarPekon Gupta <pekon@ti.com>
Reviewed-by: default avatarFelipe Balbi <balbi@ti.com>
Acked-by: default avatarTony Lindgren <tony@atomide.com>
Tested-by: default avatarEzequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: default avatarBrian Norris <computersforpeace@gmail.com>
parent ac65caf5

Documentation/devicetree/bindings/mtd/gpmc-nand.txt

+4 −4
Original line number Diff line number Diff line
@@ -22,10 +22,10 @@ Optional properties: 
				width of 8 is assumed.



 - ti,nand-ecc-opt:		A string setting the ECC layout to use. One of:



		"sw"		Software method (default)

		"hw"		Hardware method

		"hw-romcode"	gpmc hamming mode method & romcode layout

		"sw"		<deprecated> use "ham1" instead

		"hw"		<deprecated> use "ham1" instead

		"hw-romcode"	<deprecated> use "ham1" instead

		"ham1"		1-bit Hamming ecc code

		"bch4"		4-bit BCH ecc code

		"bch8"		8-bit BCH ecc code

arch/arm/mach-omap2/board-flash.c

+1 −1
Original line number Diff line number Diff line
@@ -142,7 +142,7 @@ __init board_nand_init(struct mtd_partition *nand_parts, u8 nr_parts, u8 cs, 
	board_nand_data.nr_parts	= nr_parts;

	board_nand_data.devsize		= nand_type;



	board_nand_data.ecc_opt = OMAP_ECC_HAMMING_CODE_DEFAULT;

	board_nand_data.ecc_opt = OMAP_ECC_BCH8_CODE_HW;

	gpmc_nand_init(&board_nand_data, gpmc_t);

}

#endif /* CONFIG_MTD_NAND_OMAP2 || CONFIG_MTD_NAND_OMAP2_MODULE */

drivers/mtd/nand/omap2.c

+3 −6
Original line number Diff line number Diff line
@@ -1993,10 +1993,7 @@ static int omap_nand_probe(struct platform_device *pdev) 
	}



	/* select the ecc type */

	if (pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_DEFAULT)

		info->nand.ecc.mode = NAND_ECC_SOFT;

	else if ((pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_HW) ||

		(pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_HW_ROMCODE)) {

	if (pdata->ecc_opt == OMAP_ECC_HAM1_CODE_HW) {

		info->nand.ecc.bytes            = 3;

		info->nand.ecc.size             = 512;

		info->nand.ecc.strength         = 1;
@@ -2025,7 +2022,7 @@ static int omap_nand_probe(struct platform_device *pdev) 
	}



	/* rom code layout */

	if (pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_HW_ROMCODE) {

	if (pdata->ecc_opt == OMAP_ECC_HAM1_CODE_HW) {



		if (info->nand.options & NAND_BUSWIDTH_16)

			offset = 2;
@@ -2033,7 +2030,7 @@ static int omap_nand_probe(struct platform_device *pdev) 
			offset = 1;

			info->nand.badblock_pattern = &bb_descrip_flashbased;

		}

		omap_oobinfo.eccbytes = 3 * (info->mtd.oobsize/16);

		omap_oobinfo.eccbytes = 3 * (info->mtd.writesize / 512);

		for (i = 0; i < omap_oobinfo.eccbytes; i++)

			omap_oobinfo.eccpos[i] = i+offset;

include/linux/platform_data/mtd-nand-omap2.h

+1 −6
Original line number Diff line number Diff line
@@ -23,13 +23,8 @@ enum nand_io { 
};



enum omap_ecc {

		/* 1-bit ecc: stored at end of spare area */

	OMAP_ECC_HAMMING_CODE_DEFAULT = 0, /* Default, s/w method */

	OMAP_ECC_HAMMING_CODE_HW, /* gpmc to detect the error */

		/* 1-bit ecc: stored at beginning of spare area as romcode */

	OMAP_ECC_HAMMING_CODE_HW_ROMCODE, /* gpmc method & romcode layout */

	/* 1-bit  ECC calculation by GPMC, Error detection by Software */

	OMAP_ECC_HAM1_CODE_HW,

	OMAP_ECC_HAM1_CODE_HW = 0,

	/* 4-bit  ECC calculation by GPMC, Error detection by Software */

	OMAP_ECC_BCH4_CODE_HW_DETECTION_SW,

	/* 4-bit  ECC calculation by GPMC, Error detection by ELM */

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