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: Stefan Roese <sr@denx.de>
Signed-off-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c
index e536267..fa81436 100644
--- a/drivers/mtd/nand/omap2.c
+++ b/drivers/mtd/nand/omap2.c
@@ -1122,54 +1122,8 @@
}
#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 @@
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 @@
/* 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 @@
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 /