omap3: nand: making ecc layout as compatible with romcode ecc

This patch overrides nand ecc layout and bad block descriptor (for 8-bit
device) to support hw ecc in romcode layout. So as to have in sync with ecc
layout throughout; i.e. x-loader, u-boot and kernel.

This enables to flash x-loader, u-boot, kernel, FS images from kernel itself
and compatiable with other tools.

This patch does not enables this feature by default and need to pass from
board file to enable for any board.

Signed-off-by: Vimal Singh <vimalsingh@ti.com>
Signed-off-by: Sukumar Ghorai <s-ghorai@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

diff --git a/arch/arm/plat-omap/include/plat/gpmc.h b/arch/arm/plat-omap/include/plat/gpmc.h
index 773351bc25a2236dc603a016b69286c169a942d5..12b316165037adf13549092734393478058e91c7 100644 (file)
--- a/arch/arm/plat-omap/include/plat/gpmc.h
+++ b/arch/arm/plat-omap/include/plat/gpmc.h
@@ -90,6 +90,8 @@ 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 begining of spare area as romcode */
+       OMAP_ECC_HAMMING_CODE_HW_ROMCODE, /* gpmc method & romcode layout */
 };
 
 /*

diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c
index 6d4a42e393801cf9aa5a9557b2d41308bab27342..4e33972ad17ac780a55c4e96c1350055c23ad92a 100644 (file)
--- a/drivers/mtd/nand/omap2.c
+++ b/drivers/mtd/nand/omap2.c
@@ -98,6 +98,20 @@
 static const char *part_probes[] = { "cmdlinepart", NULL };
 #endif
 
+/* oob info generated runtime depending on ecc algorithm and layout selected */
+static struct nand_ecclayout omap_oobinfo;
+/* Define some generic bad / good block scan pattern which are used
+ * while scanning a device for factory marked good / bad blocks
+ */
+static uint8_t scan_ff_pattern[] = { 0xff };
+static struct nand_bbt_descr bb_descrip_flashbased = {
+       .options = NAND_BBT_SCANEMPTY | NAND_BBT_SCANALLPAGES,
+       .offs = 0,
+       .len = 1,
+       .pattern = scan_ff_pattern,
+};
+
+
 struct omap_nand_info {
        struct nand_hw_control          controller;
        struct omap_nand_platform_data  *pdata;
@@ -914,6 +928,7 @@ static int __devinit omap_nand_probe(struct platform_device *pdev)
        struct omap_nand_info           *info;
        struct omap_nand_platform_data  *pdata;
        int                             err;
+       int                             i, offset;
 
        pdata = pdev->dev.platform_data;
        if (pdata == NULL) {
@@ -1037,7 +1052,8 @@ static int __devinit omap_nand_probe(struct platform_device *pdev)
        /* selsect 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) {
+       else if ((pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_HW) ||
+               (pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_HW_ROMCODE)) {
                info->nand.ecc.bytes            = 3;
                info->nand.ecc.size             = 512;
                info->nand.ecc.calculate        = omap_calculate_ecc;
@@ -1057,6 +1073,25 @@ static int __devinit omap_nand_probe(struct platform_device *pdev)
                }
        }
 
+       /* rom code layout */
+       if (pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_HW_ROMCODE) {
+
+               if (info->nand.options & NAND_BUSWIDTH_16)
+                       offset = 2;
+               else {
+                       offset = 1;
+                       info->nand.badblock_pattern = &bb_descrip_flashbased;
+               }
+               omap_oobinfo.eccbytes = 3 * (info->mtd.oobsize/16);
+               for (i = 0; i < omap_oobinfo.eccbytes; i++)
+                       omap_oobinfo.eccpos[i] = i+offset;
+
+               omap_oobinfo.oobfree->offset = offset + omap_oobinfo.eccbytes;
+               omap_oobinfo.oobfree->length = info->mtd.oobsize -
+                                       (offset + omap_oobinfo.eccbytes);
+
+               info->nand.ecc.layout = &omap_oobinfo;
+       }
 
 #ifdef CONFIG_MTD_PARTITIONS
        err = parse_mtd_partitions(&info->mtd, part_probes, &info->parts, 0);