omap: gpmc: 'nandecc sw' can use HAM1 or BCH8

The 'nandecc sw' command selects a software-based error correction
algorithm.  By default, this is OMAP_ECC_HAM1_CODE_SW but some
platforms use OMAP_ECC_BCH8_CODE_HW_DETECTION_SW as their
software-based correction algorithm.  Allow a user to be specific e.g.
 # nandecc sw <hamming|bch8>
where 'hamming' is still the default.

Note: we don't just use CONFIG_NAND_OMAP_ECCSCHEME as it might be set
      to a hardware-based ECC scheme---a little strange when the user
      has requested 'sw' ECC.

Signed-off-by: Ash Charles <ashcharles@gmail.com>

diff --git a/arch/arm/cpu/armv7/omap3/board.c b/arch/arm/cpu/armv7/omap3/board.c
index 347947c..dd53b20 100644 (file)
--- a/arch/arm/cpu/armv7/omap3/board.c
+++ b/arch/arm/cpu/armv7/omap3/board.c
@@ -347,7 +347,16 @@ static int do_switch_ecc(cmd_tbl_t * cmdtp, int flag, int argc, char * const arg
                                goto usage;
                }
        } else if (strncmp(argv[1], "sw", 2) == 0) {
-               omap_nand_switch_ecc(0, 0);
+               if (argc == 2) {
+                       omap_nand_switch_ecc(0, 1);
+               } else {
+                       if (strncmp(argv[2], "hamming", 7) == 0)
+                               omap_nand_switch_ecc(0, 1);
+                       else if (strncmp(argv[2], "bch8", 4) == 0)
+                               omap_nand_switch_ecc(0, 8);
+                       else
+                               goto usage;
+               }
        } else {
                goto usage;
        }

diff --git a/drivers/mtd/nand/omap_gpmc.c b/drivers/mtd/nand/omap_gpmc.c
index f8b0063..610f969 100644 (file)
--- a/drivers/mtd/nand/omap_gpmc.c
+++ b/drivers/mtd/nand/omap_gpmc.c
@@ -912,8 +912,18 @@ int __maybe_unused omap_nand_switch_ecc(uint32_t hardware, uint32_t eccstrength)
                        return -EINVAL;
                }
        } else {
-               err = omap_select_ecc_scheme(nand, OMAP_ECC_HAM1_CODE_SW,
+               if (eccstrength == 1) {
+                       err = omap_select_ecc_scheme(nand,
+                                       OMAP_ECC_HAM1_CODE_SW,
+                                       mtd->writesize, mtd->oobsize);
+               } else if (eccstrength == 8) {
+                       err = omap_select_ecc_scheme(nand,
+                                       OMAP_ECC_BCH8_CODE_HW_DETECTION_SW,
                                        mtd->writesize, mtd->oobsize);
+               } else {
+                       printf("nand: error: unsupported ECC scheme\n");
+                       return -EINVAL;
+               }
        }
 
        /* Update NAND handling after ECC mode switch */