Commit 7bcd1dca authored by Pekon Gupta's avatar Pekon Gupta Committed by Brian Norris
Browse files

mtd: nand: omap: ecc.calculate: merge omap3_calculate_ecc_bch8 in omap_calculate_ecc_bch 



merge omap3_calculate_ecc_bch8() into omap_calculate_ecc_bch() so that
common callback can be used for both OMAP_ECC_BCH8_CODE_HW and
OMAP_ECC_BCH8_CODE_HW_DETECTION_SW
+---------------------+-------------------------------------------------------+
|ecc-scheme           | nand_chip->calculate() after this patch               |
+---------------------+-------------------------------------------------------+
|HAM1_ECC             | omap_calculate_ecc()                                  |
+---------------------+-------------------------------------------------------+
|BCH4_HW_DETECTION_SW | omap_calculate_ecc_bch()                              |
|BCH4_HW              | omap_calculate_ecc_bch()                              |
|BCH8_HW_DETECTION_SW | omap3_calculate_ecc_bch8() -> omap_calculate_ecc_bch()|
|BCH8_HW              | omap_calculate_ecc_bch()                              |
+---------------------+-------------------------------------------------------+

Tested-by: default avatarStefan Roese <sr@denx.de>
Signed-off-by: default avatarPekon Gupta <pekon@ti.com>
Signed-off-by: default avatarBrian Norris <computersforpeace@gmail.com>
parent 2c9f2365

drivers/mtd/nand/omap2.c

+10 −49
Original line number Diff line number Diff line
@@ -1122,54 +1122,8 @@ static void omap3_enable_hwecc_bch(struct mtd_info *mtd, int mode) 
}

#endif

static u8  bch4_polynomial[] = {0x28, 0x13, 0xcc, 0x39, 0x96, 0xac, 0x7f};



#ifdef CONFIG_MTD_NAND_ECC_BCH

/**

 * omap3_calculate_ecc_bch8 - Generate 13 bytes of ECC bytes

 * @mtd: MTD device structure

 * @dat: The pointer to data on which ecc is computed

 * @ecc_code: The ecc_code buffer

 */

static int omap3_calculate_ecc_bch8(struct mtd_info *mtd, const u_char *dat,

				    u_char *ecc_code)

{

	struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,

						   mtd);

	unsigned long nsectors, val1, val2, val3, val4;

	int i;



	nsectors = ((readl(info->reg.gpmc_ecc_config) >> 4) & 0x7) + 1;



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



		/* Read hw-computed remainder */

		val1 = readl(info->reg.gpmc_bch_result0[i]);

		val2 = readl(info->reg.gpmc_bch_result1[i]);

		val3 = readl(info->reg.gpmc_bch_result2[i]);

		val4 = readl(info->reg.gpmc_bch_result3[i]);



		/*

		 * Add constant polynomial to remainder, in order to get an ecc

		 * sequence of 0xFFs for a buffer filled with 0xFFs.

		 */

		*ecc_code++ = 0xef ^ (val4 & 0xFF);

		*ecc_code++ = 0x51 ^ ((val3 >> 24) & 0xFF);

		*ecc_code++ = 0x2e ^ ((val3 >> 16) & 0xFF);

		*ecc_code++ = 0x09 ^ ((val3 >> 8) & 0xFF);

		*ecc_code++ = 0xed ^ (val3 & 0xFF);

		*ecc_code++ = 0x93 ^ ((val2 >> 24) & 0xFF);

		*ecc_code++ = 0x9a ^ ((val2 >> 16) & 0xFF);

		*ecc_code++ = 0xc2 ^ ((val2 >> 8) & 0xFF);

		*ecc_code++ = 0x97 ^ (val2 & 0xFF);

		*ecc_code++ = 0x79 ^ ((val1 >> 24) & 0xFF);

		*ecc_code++ = 0xe5 ^ ((val1 >> 16) & 0xFF);

		*ecc_code++ = 0x24 ^ ((val1 >> 8) & 0xFF);

		*ecc_code++ = 0xb5 ^ (val1 & 0xFF);

	}



	return 0;

}

#endif /* CONFIG_MTD_NAND_ECC_BCH */

static u8  bch8_polynomial[] = {0xef, 0x51, 0x2e, 0x09, 0xed, 0x93, 0x9a, 0xc2,

				0x97, 0x79, 0xe5, 0x24, 0xb5};



/**

 * omap_calculate_ecc_bch - Generate bytes of ECC bytes
@@ -1194,6 +1148,7 @@ static int __maybe_unused omap_calculate_ecc_bch(struct mtd_info *mtd, 
	for (i = 0; i < nsectors; i++) {

		ecc_code = ecc_calc;

		switch (info->ecc_opt) {

		case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:

		case OMAP_ECC_BCH8_CODE_HW:

			bch_val1 = readl(gpmc_regs->gpmc_bch_result0[i]);

			bch_val2 = readl(gpmc_regs->gpmc_bch_result1[i]);
@@ -1242,6 +1197,12 @@ static int __maybe_unused omap_calculate_ecc_bch(struct mtd_info *mtd, 
			/* Set  8th ECC byte as 0x0 for ROM compatibility */

			ecc_calc[eccbytes - 1] = 0x0;

			break;

		case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:

			/* Add constant polynomial to remainder, so that

			 * ECC of blank pages results in 0x0 on reading back */

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

				ecc_calc[i] ^= bch8_polynomial[i];

			break;

		case OMAP_ECC_BCH8_CODE_HW:

			/* Set 14th ECC byte as 0x0 for ROM compatibility */

			ecc_calc[eccbytes - 1] = 0x0;
@@ -1879,7 +1840,7 @@ static int omap_nand_probe(struct platform_device *pdev) 
		nand_chip->ecc.strength		= 8;

		nand_chip->ecc.hwctl		= omap3_enable_hwecc_bch;

		nand_chip->ecc.correct		= nand_bch_correct_data;

		nand_chip->ecc.calculate	= omap3_calculate_ecc_bch8;

		nand_chip->ecc.calculate	= omap_calculate_ecc_bch;

		/* define ECC layout */

		ecclayout->eccbytes		= nand_chip->ecc.bytes *

							(mtd->writesize /

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