2 files changed, 61 insertions, 1 deletions

diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 17bbd5062027..22113865438b 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -979,6 +979,54 @@ static int nand_read_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
 }
 
 /**
+ * nand_read_page_hwecc_oob_first - [REPLACABLE] hw ecc, read oob first
+ * @mtd:        mtd info structure
+ * @chip:       nand chip info structure
+ * @buf:        buffer to store read data
+ *
+ * Hardware ECC for large page chips, require OOB to be read first.
+ * For this ECC mode, the write_page method is re-used from ECC_HW.
+ * These methods read/write ECC from the OOB area, unlike the
+ * ECC_HW_SYNDROME support with multiple ECC steps, follows the
+ * "infix ECC" scheme and reads/writes ECC from the data area, by
+ * overwriting the NAND manufacturer bad block markings.
+ */
+static int nand_read_page_hwecc_oob_first(struct mtd_info *mtd,
+        struct nand_chip *chip, uint8_t *buf, int page)
+{
+        int i, eccsize = chip->ecc.size;
+        int eccbytes = chip->ecc.bytes;
+        int eccsteps = chip->ecc.steps;
+        uint8_t *p = buf;
+        uint8_t *ecc_code = chip->buffers->ecccode;
+        uint32_t *eccpos = chip->ecc.layout->eccpos;
+        uint8_t *ecc_calc = chip->buffers->ecccalc;
+
+        /* Read the OOB area first */
+        chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
+        chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
+        chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page);
+
+        for (i = 0; i < chip->ecc.total; i++)
+                ecc_code[i] = chip->oob_poi[eccpos[i]];
+
+        for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
+                int stat;
+
+                chip->ecc.hwctl(mtd, NAND_ECC_READ);
+                chip->read_buf(mtd, p, eccsize);
+                chip->ecc.calculate(mtd, p, &ecc_calc[i]);
+
+                stat = chip->ecc.correct(mtd, p, &ecc_code[i], NULL);
+                if (stat < 0)
+                        mtd->ecc_stats.failed++;
+                else
+                        mtd->ecc_stats.corrected += stat;
+        }
+        return 0;
+}
+
+/**
  * nand_read_page_syndrome - [REPLACABLE] hardware ecc syndrom based page read
  * @mtd:        mtd info structure
  * @chip:       nand chip info structure
@@ -2673,6 +2721,17 @@ int nand_scan_tail(struct mtd_info *mtd)
          */
 
         switch (chip->ecc.mode) {
+        case NAND_ECC_HW_OOB_FIRST:
+                /* Similar to NAND_ECC_HW, but a separate read_page handle */
+                if (!chip->ecc.calculate || !chip->ecc.correct ||
+                     !chip->ecc.hwctl) {
+                        printk(KERN_WARNING "No ECC functions supplied; "
+                               "Hardware ECC not possible\n");
+                        BUG();
+                }
+                if (!chip->ecc.read_page)
+                        chip->ecc.read_page = nand_read_page_hwecc_oob_first;
+
         case NAND_ECC_HW:
                 /* Use standard hwecc read page function ? */
                 if (!chip->ecc.read_page)
@@ -2695,7 +2754,7 @@ int nand_scan_tail(struct mtd_info *mtd)
                      chip->ecc.read_page == nand_read_page_hwecc ||
                      !chip->ecc.write_page ||
                      chip->ecc.write_page == nand_write_page_hwecc)) {
-                        printk(KERN_WARNING "No ECC functions supplied, "
+                        printk(KERN_WARNING "No ECC functions supplied; "
                                "Hardware ECC not possible\n");
                         BUG();
                 }
diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
index 686f3701f2f4..7a232a9bdd62 100644
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h
@@ -121,6 +121,7 @@ typedef enum {
         NAND_ECC_SOFT,
         NAND_ECC_HW,
         NAND_ECC_HW_SYNDROME,
+        NAND_ECC_HW_OOB_FIRST,
 } nand_ecc_modes_t;
 
 /*