mxc_nand: allow swapping the Bad block Indicator for NFC v1

Swap the BI-byte on position 0x7D0 with a data byte at 0x835.  To fix a bug
in Freescale imx NFC v1 SoC's for 2K page NAND flashes: imx27 and imx31.
Warning: The same solution needs to be applied to the boot loader and the
flash programmer.

Signed-off-by: Gaëtan Carlier <gcembed@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

diff --git a/arch/arm/plat-mxc/include/mach/mxc_nand.h b/arch/arm/plat-mxc/include/mach/mxc_nand.h
index 6bb96ef1600bc7ac384fec802d53018b78f6823c..7c044374ce612ab3416c227c068e7a4d6cc2a3e2 100644 (file)
--- a/arch/arm/plat-mxc/include/mach/mxc_nand.h
+++ b/arch/arm/plat-mxc/include/mach/mxc_nand.h
@@ -26,6 +26,8 @@ struct mxc_nand_platform_data {
        unsigned int width;     /* data bus width in bytes */
        unsigned int hw_ecc:1;  /* 0 if suppress hardware ECC */
        unsigned int flash_bbt:1; /* set to 1 to use a flash based bbt */
+       unsigned int biswap:1;  /* set to 1 to swap the Bad Block Indicator
+                                  NFC v1 workaround */
        struct mtd_partition *parts;    /* partition table */
        int nr_parts;                   /* size of parts */
 };

diff --git a/drivers/mtd/nand/mxc_nand.c b/drivers/mtd/nand/mxc_nand.c
index bfee9ebf9ab9f7f91a40444da75d8ee01aad6c11..e59a45f3fc6bb8ea56e5355fdb1179e6b9d8e0f8 100644 (file)
--- a/drivers/mtd/nand/mxc_nand.c
+++ b/drivers/mtd/nand/mxc_nand.c
@@ -682,6 +682,26 @@ static int mxc_nand_calculate_ecc(struct mtd_info *mtd, const u_char *dat,
        return 0;
 }
 
+/*
+ * Swap the BI-byte on position 0x7D0 with a data byte at 0x835.
+ * To fix a bug in NFC v1 SoC's for 2K page NAND flashes: imx27 and imx31.
+ * Warning: The same solution needs to be applied to the boot loader and the
+ * flash programmer.
+ */
+static void nfcv1_bi_swap_quirk(struct mtd_info *mtd)
+{
+       struct nand_chip *nand_chip = mtd->priv;
+       struct mxc_nand_host *host = nand_chip->priv;
+       unsigned short temp1, temp2, new_temp1;
+
+       temp1 = ioread16(host->main_area0 + 0x7D0);
+       temp2 = ioread16(host->main_area0 + 0x834);
+       new_temp1 = (temp1 & 0xFF00) | (temp2 >> 8);
+       temp2 = (temp2 & 0x00FF) | (temp1 << 8);
+       iowrite16(new_temp1, host->main_area0 + 0x7D0);
+       iowrite16(temp2, host->main_area0 + 0x834);
+}
+
 static u_char mxc_nand_read_byte(struct mtd_info *mtd)
 {
        struct nand_chip *nand_chip = mtd->priv;
@@ -1085,6 +1105,9 @@ static void mxc_nand_command(struct mtd_info *mtd, unsigned command,
 
                host->devtype_data->send_page(mtd, NFC_OUTPUT);
 
+               if ((mtd->writesize > 512) && nfc_is_v1() && host->pdata.biswap)
+                       nfcv1_bi_swap_quirk(mtd);
+
                memcpy32_fromio(host->data_buf, host->main_area0,
                                mtd->writesize);
                copy_spare(mtd, true);
@@ -1104,6 +1127,9 @@ static void mxc_nand_command(struct mtd_info *mtd, unsigned command,
        case NAND_CMD_PAGEPROG:
                memcpy32_toio(host->main_area0, host->data_buf, mtd->writesize);
                copy_spare(mtd, false);
+               if ((mtd->writesize > 512) && nfc_is_v1() && host->pdata.biswap)
+                       nfcv1_bi_swap_quirk(mtd);
+
                host->devtype_data->send_page(mtd, NFC_INPUT);
                host->devtype_data->send_cmd(host, command, true);
                mxc_do_addr_cycle(mtd, column, page_addr);