nand: arasan_nfc: Add support for ondie ecc

This patch adds support for ondie ecc. As of now
this adds support for micron parts which supports
ondie ecc.
Didn't found any better way to detect ondie ecc
support by a device except sorting out with
manufacture and device id's.

Signed-off-by: Siva Durga Prasad Paladugu <sivadur@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

diff --git a/drivers/mtd/nand/arasan_nfc.c b/drivers/mtd/nand/arasan_nfc.c
index dc956f81e49b726c03e26cb56430f97f03e7b3b9..70cb00e85fbd59f6d8cfeabb7da4d2b99da392a3 100644 (file)
--- a/drivers/mtd/nand/arasan_nfc.c
+++ b/drivers/mtd/nand/arasan_nfc.c
@@ -21,6 +21,7 @@
 struct arasan_nand_info {
        void __iomem *nand_base;
        u32 page;
+       bool on_die_ecc_enabled;
 };
 
 struct nand_regs {
@@ -64,6 +65,7 @@ struct arasan_nand_command_format {
 };
 
 #define ONDIE_ECC_FEATURE_ADDR                 0x90
+#define ENABLE_ONDIE_ECC                       0x08
 
 #define ARASAN_PROG_RD_MASK                    0x00000001
 #define ARASAN_PROG_BLK_ERS_MASK               0x00000004
@@ -206,6 +208,51 @@ static const struct arasan_ecc_matrix ecc_matrix[] = {
        {16384, 1024, 24, 1, 4, 0x4220, 0x2A0}
 };
 
+static struct nand_ecclayout ondie_nand_oob_64 = {
+       .eccbytes = 32,
+
+       .eccpos = {
+               8, 9, 10, 11, 12, 13, 14, 15,
+               24, 25, 26, 27, 28, 29, 30, 31,
+               40, 41, 42, 43, 44, 45, 46, 47,
+               56, 57, 58, 59, 60, 61, 62, 63
+       },
+
+       .oobfree = {
+               { .offset = 4, .length = 4 },
+               { .offset = 20, .length = 4 },
+               { .offset = 36, .length = 4 },
+               { .offset = 52, .length = 4 }
+       }
+};
+
+/*
+ * bbt decriptors for chips with on-die ECC and
+ * chips with 64-byte OOB
+ */
+static u8 bbt_pattern[] = {'B', 'b', 't', '0' };
+static u8 mirror_pattern[] = {'1', 't', 'b', 'B' };
+
+static struct nand_bbt_descr bbt_main_descr = {
+       .options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE |
+               NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
+       .offs = 4,
+       .len = 4,
+       .veroffs = 20,
+       .maxblocks = 4,
+       .pattern = bbt_pattern
+};
+
+static struct nand_bbt_descr bbt_mirror_descr = {
+       .options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE |
+               NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
+       .offs = 4,
+       .len = 4,
+       .veroffs = 20,
+       .maxblocks = 4,
+       .pattern = mirror_pattern
+};
+
 static u8 buf_data[READ_BUFF_SIZE];
 static u32 buf_index;
 
@@ -265,6 +312,7 @@ static u8 arasan_nand_get_addrcycle(struct mtd_info *mtd)
 static int arasan_nand_read_page(struct mtd_info *mtd, u8 *buf, u32 size)
 {
        struct nand_chip *chip = mtd_to_nand(mtd);
+       struct arasan_nand_info *nand = nand_get_controller_data(chip);
        u32 reg_val, i, pktsize, pktnum;
        u32 *bufptr = (u32 *)buf;
        u32 timeout;
@@ -293,15 +341,17 @@ static int arasan_nand_read_page(struct mtd_info *mtd, u8 *buf, u32 size)
                    pktsize;
        writel(reg_val, &arasan_nand_base->pkt_reg);
 
-       arasan_nand_enable_ecc();
-       addr_cycles = arasan_nand_get_addrcycle(mtd);
-       if (addr_cycles == ARASAN_NAND_INVALID_ADDR_CYCL)
-               return ERR_ADDR_CYCLE;
+       if (!nand->on_die_ecc_enabled) {
+               arasan_nand_enable_ecc();
+               addr_cycles = arasan_nand_get_addrcycle(mtd);
+               if (addr_cycles == ARASAN_NAND_INVALID_ADDR_CYCL)
+                       return ERR_ADDR_CYCLE;
 
-       writel((NAND_CMD_RNDOUTSTART << ARASAN_NAND_CMD_CMD2_SHIFT) |
-              NAND_CMD_RNDOUT | (addr_cycles <<
-              ARASAN_NAND_CMD_ADDR_CYCL_SHIFT),
-              &arasan_nand_base->ecc_sprcmd_reg);
+               writel((NAND_CMD_RNDOUTSTART << ARASAN_NAND_CMD_CMD2_SHIFT) |
+                      NAND_CMD_RNDOUT | (addr_cycles <<
+                      ARASAN_NAND_CMD_ADDR_CYCL_SHIFT),
+                      &arasan_nand_base->ecc_sprcmd_reg);
+       }
        writel(curr_cmd->pgm, &arasan_nand_base->pgm_reg);
 
        while (rdcount < pktnum) {
@@ -363,17 +413,19 @@ static int arasan_nand_read_page(struct mtd_info *mtd, u8 *buf, u32 size)
        writel(reg_val | ARASAN_NAND_INT_STS_XFR_CMPLT_MASK,
               &arasan_nand_base->intsts_reg);
 
-       if (readl(&arasan_nand_base->intsts_reg) &
-           ARASAN_NAND_INT_STS_MUL_BIT_ERR_MASK) {
-               printf("arasan rd_page:sbiterror\n");
-               return -1;
-       }
+       if (!nand->on_die_ecc_enabled) {
+               if (readl(&arasan_nand_base->intsts_reg) &
+                   ARASAN_NAND_INT_STS_MUL_BIT_ERR_MASK) {
+                       printf("arasan rd_page:sbiterror\n");
+                       return -1;
+               }
 
-       if (readl(&arasan_nand_base->intsts_reg) &
-           ARASAN_NAND_INT_STS_ERR_EN_MASK) {
-               mtd->ecc_stats.failed++;
-               printf("arasan rd_page:multibiterror\n");
-               return -1;
+               if (readl(&arasan_nand_base->intsts_reg) &
+                   ARASAN_NAND_INT_STS_ERR_EN_MASK) {
+                       mtd->ecc_stats.failed++;
+                       printf("arasan rd_page:multibiterror\n");
+                       return -1;
+               }
        }
 
        return 0;
@@ -460,12 +512,14 @@ static int arasan_nand_write_page_hwecc(struct mtd_info *mtd,
        reg_val |= (pktnum << ARASAN_NAND_PKT_REG_PKT_CNT_SHFT) | pktsize;
        writel(reg_val, &arasan_nand_base->pkt_reg);
 
-       arasan_nand_enable_ecc();
-       column_addr_cycles = (chip->onfi_params.addr_cycles &
-                             ARASAN_NAND_COL_ADDR_CYCL_MASK) >>
-                             ARASAN_NAND_COL_ADDR_CYCL_SHIFT;
-       writel((NAND_CMD_RNDIN | (column_addr_cycles << 28)),
-              &arasan_nand_base->ecc_sprcmd_reg);
+       if (!nand->on_die_ecc_enabled) {
+               arasan_nand_enable_ecc();
+               column_addr_cycles = (chip->onfi_params.addr_cycles &
+                                     ARASAN_NAND_COL_ADDR_CYCL_MASK) >>
+                                     ARASAN_NAND_COL_ADDR_CYCL_SHIFT;
+               writel((NAND_CMD_RNDIN | (column_addr_cycles << 28)),
+                      &arasan_nand_base->ecc_sprcmd_reg);
+       }
        writel(curr_cmd->pgm, &arasan_nand_base->pgm_reg);
 
        while (rdcount < pktnum) {
@@ -1032,6 +1086,50 @@ static void arasan_nand_cmd_function(struct mtd_info *mtd, unsigned int command,
                printf("ERROR:%s:command:0x%x\n", __func__, curr_cmd->cmd1);
 }
 
+static void arasan_check_ondie(struct mtd_info *mtd)
+{
+       struct nand_chip *nand_chip = mtd_to_nand(mtd);
+       struct arasan_nand_info *nand = nand_get_controller_data(nand_chip);
+       u8 maf_id, dev_id;
+       u8 get_feature[4];
+       u8 set_feature[4] = {ENABLE_ONDIE_ECC, 0x00, 0x00, 0x00};
+       u32 i;
+
+       /* Send the command for reading device ID */
+       nand_chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
+       nand_chip->cmdfunc(mtd, NAND_CMD_READID, 0, -1);
+
+       /* Read manufacturer and device IDs */
+       maf_id = nand_chip->read_byte(mtd);
+       dev_id = nand_chip->read_byte(mtd);
+
+       if ((maf_id == NAND_MFR_MICRON) &&
+           ((dev_id == 0xf1) || (dev_id == 0xa1) || (dev_id == 0xb1) ||
+            (dev_id == 0xaa) || (dev_id == 0xba) || (dev_id == 0xda) ||
+            (dev_id == 0xca) || (dev_id == 0xac) || (dev_id == 0xbc) ||
+            (dev_id == 0xdc) || (dev_id == 0xcc) || (dev_id == 0xa3) ||
+            (dev_id == 0xb3) || (dev_id == 0xd3) || (dev_id == 0xc3))) {
+               nand_chip->cmdfunc(mtd, NAND_CMD_SET_FEATURES,
+                                  ONDIE_ECC_FEATURE_ADDR, -1);
+
+               nand_chip->write_buf(mtd, &set_feature[0], 4);
+               nand_chip->cmdfunc(mtd, NAND_CMD_GET_FEATURES,
+                                  ONDIE_ECC_FEATURE_ADDR, -1);
+
+               for (i = 0; i < 4; i++)
+                       get_feature[i] = nand_chip->read_byte(mtd);
+
+               if (get_feature[0] & ENABLE_ONDIE_ECC)
+                       nand->on_die_ecc_enabled = true;
+               else
+                       printf("%s: Unable to enable OnDie ECC\n", __func__);
+
+               /* Use the BBT pattern descriptors */
+               nand_chip->bbt_td = &bbt_main_descr;
+               nand_chip->bbt_md = &bbt_mirror_descr;
+       }
+}
+
 static int arasan_nand_ecc_init(struct mtd_info *mtd)
 {
        int found = -1;
@@ -1126,9 +1224,22 @@ static int arasan_nand_init(struct nand_chip *nand_chip, int devnum)
        nand_chip->ecc.read_oob = arasan_nand_read_oob;
        nand_chip->ecc.write_oob = arasan_nand_write_oob;
 
-       if (arasan_nand_ecc_init(mtd)) {
-               printf("%s: nand_ecc_init failed\n", __func__);
-               goto fail;
+       arasan_check_ondie(mtd);
+
+       /*
+        * If on die supported, then give priority to on-die ecc and use
+        * it instead of controller ecc.
+        */
+       if (nand->on_die_ecc_enabled) {
+               nand_chip->ecc.strength = 1;
+               nand_chip->ecc.size = mtd->writesize;
+               nand_chip->ecc.bytes = 0;
+               nand_chip->ecc.layout = &ondie_nand_oob_64;
+       } else {
+               if (arasan_nand_ecc_init(mtd)) {
+                       printf("%s: nand_ecc_init failed\n", __func__);
+                       goto fail;
+               }
        }
 
        if (nand_scan_tail(mtd)) {