[MTD] [NAND] Blackfin NFC Driver: add support for the ECC layout the Blackfin bootrom uses

Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

2 files changed, 52 insertions, 0 deletions

diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig
index 71406e517857..c075b47e11ad 100644
--- a/drivers/mtd/nand/Kconfig
+++ b/drivers/mtd/nand/Kconfig
@@ -109,6 +109,18 @@ config MTD_NAND_BF5XX_HWECC
           Enable the use of the BF5XX's internal ECC generator when
           using NAND.
 
+config MTD_NAND_BF5XX_BOOTROM_ECC
+        bool "Use Blackfin BootROM ECC Layout"
+        default n
+        depends on MTD_NAND_BF5XX_HWECC
+        help
+          If you wish to modify NAND pages and allow the Blackfin on-chip
+          BootROM to boot from them, say Y here.  This is only necessary
+          if you are booting U-Boot out of NAND and you wish to update
+          U-Boot from Linux' userspace.  Otherwise, you should say N here.
+
+          If unsure, say N.
+
 config MTD_NAND_RTC_FROM4
         tristate "Renesas Flash ROM 4-slot interface board (FROM_BOARD4)"
         depends on SH_SOLUTION_ENGINE
diff --git a/drivers/mtd/nand/bf5xx_nand.c b/drivers/mtd/nand/bf5xx_nand.c
index fc58afe4733a..3555f6b3ebe0 100644
--- a/drivers/mtd/nand/bf5xx_nand.c
+++ b/drivers/mtd/nand/bf5xx_nand.c
@@ -91,6 +91,41 @@ static const unsigned short bfin_nfc_pin_req[] =
          P_NAND_ALE,
          0};
 
+#ifdef CONFIG_MTD_NAND_BF5XX_BOOTROM_ECC
+static uint8_t bbt_pattern[] = { 0xff };
+
+static struct nand_bbt_descr bootrom_bbt = {
+        .options = 0,
+        .offs = 63,
+        .len = 1,
+        .pattern = bbt_pattern,
+};
+
+static struct nand_ecclayout bootrom_ecclayout = {
+        .eccbytes = 24,
+        .eccpos = {
+                0x8 * 0, 0x8 * 0 + 1, 0x8 * 0 + 2,
+                0x8 * 1, 0x8 * 1 + 1, 0x8 * 1 + 2,
+                0x8 * 2, 0x8 * 2 + 1, 0x8 * 2 + 2,
+                0x8 * 3, 0x8 * 3 + 1, 0x8 * 3 + 2,
+                0x8 * 4, 0x8 * 4 + 1, 0x8 * 4 + 2,
+                0x8 * 5, 0x8 * 5 + 1, 0x8 * 5 + 2,
+                0x8 * 6, 0x8 * 6 + 1, 0x8 * 6 + 2,
+                0x8 * 7, 0x8 * 7 + 1, 0x8 * 7 + 2
+        },
+        .oobfree = {
+                { 0x8 * 0 + 3, 5 },
+                { 0x8 * 1 + 3, 5 },
+                { 0x8 * 2 + 3, 5 },
+                { 0x8 * 3 + 3, 5 },
+                { 0x8 * 4 + 3, 5 },
+                { 0x8 * 5 + 3, 5 },
+                { 0x8 * 6 + 3, 5 },
+                { 0x8 * 7 + 3, 5 },
+        }
+};
+#endif
+
 /*
  * Data structures for bf5xx nand flash controller driver
  */
@@ -712,6 +747,11 @@ static int bf5xx_nand_probe(struct platform_device *pdev)
 
         /* setup hardware ECC data struct */
         if (hardware_ecc) {
+#ifdef CONFIG_MTD_NAND_BF5XX_BOOTROM_ECC
+                chip->badblock_pattern = &bootrom_bbt;
+                chip->ecc.layout = &bootrom_ecclayout;
+#endif
+
                 if (plat->page_size == NFC_PG_SIZE_256) {
                         chip->ecc.bytes = 3;
                         chip->ecc.size = 256;