[PATCH RFC v3 3/4] nand: pl353: Add ONDIE ECC support
Punnaiah Choudary Kalluri
punnaiah.choudary.kalluri at xilinx.com
Thu Jun 26 20:03:58 PDT 2014
Added ONDIE ECC support. Currently this ecc mode is supported for
specific micron parts with oob size 64 bytes.
Signed-off-by: Punnaiah Choudary Kalluri <punnaia at xilinx.com>
---
drivers/mtd/nand/pl353_nand.c | 131 +++++++++++++++++++++++++++++++++++++++-
1 files changed, 127 insertions(+), 4 deletions(-)
diff --git a/drivers/mtd/nand/pl353_nand.c b/drivers/mtd/nand/pl353_nand.c
index eca205f..4f56c7f 100644
--- a/drivers/mtd/nand/pl353_nand.c
+++ b/drivers/mtd/nand/pl353_nand.c
@@ -140,6 +140,48 @@ static struct nand_ecclayout nand_oob_64 = {
.length = 50} }
};
+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 }
+ }
+};
+
+/* Generic flash bbt decriptors */
+static uint8_t bbt_pattern[] = { 'B', 'b', 't', '0' };
+static uint8_t 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
+};
+
/**
* pl353_nand_calculate_hwecc - Calculate Hardware ECC
* @mtd: Pointer to the mtd_info structure
@@ -816,15 +858,74 @@ static int pl353_nand_device_ready(struct mtd_info *mtd)
}
/**
+ * pl353_nand_detect_ondie_ecc - Get the flash ondie ecc state
+ * @mtd: Pointer to the mtd_info structure
+ *
+ * This function enables the ondie ecc for the Micron ondie ecc capable devices
+ *
+ * Return: 1 on detect, 0 if fail to detect
+ */
+static int pl353_nand_detect_ondie_ecc(struct mtd_info *mtd)
+{
+ struct nand_chip *nand_chip = mtd->priv;
+ u8 maf_id, dev_id, i, get_feature;
+ u8 set_feature[4] = { 0x08, 0x00, 0x00, 0x00 };
+
+ /* Check if On-Die ECC flash */
+ nand_chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
+ nand_chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
+
+ /* Read manufacturer and device IDs */
+ maf_id = readb(nand_chip->IO_ADDR_R);
+ dev_id = readb(nand_chip->IO_ADDR_R);
+
+ 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_GET_FEATURES,
+ ONDIE_ECC_FEATURE_ADDR, -1);
+ get_feature = readb(nand_chip->IO_ADDR_R);
+
+ if (get_feature & 0x08) {
+ return 1;
+ } else {
+ nand_chip->cmdfunc(mtd, NAND_CMD_SET_FEATURES,
+ ONDIE_ECC_FEATURE_ADDR, -1);
+ for (i = 0; i < 4; i++)
+ writeb(set_feature[i], nand_chip->IO_ADDR_W);
+
+ ndelay(1000);
+
+ nand_chip->cmdfunc(mtd, NAND_CMD_GET_FEATURES,
+ ONDIE_ECC_FEATURE_ADDR, -1);
+ get_feature = readb(nand_chip->IO_ADDR_R);
+
+ if (get_feature & 0x08)
+ return 1;
+ }
+ }
+
+ return 0;
+}
+
+/**
* pl353_nand_ecc_init - Initialize the ecc information as per the ecc mode
* @mtd: Pointer to the mtd_info structure
+ * @ondie_ecc_state: ondie ecc status
*
* This function initializes the ecc block and functional pointers as per the
* ecc mode
*
* Return: Zero on success and error on failure.
*/
-static int pl353_nand_ecc_init(struct mtd_info *mtd)
+static int pl353_nand_ecc_init(struct mtd_info *mtd, int ondie_ecc_state)
{
struct nand_chip *nand_chip = mtd->priv;
struct pl353_nand_info *xnand =
@@ -838,12 +939,28 @@ static int pl353_nand_ecc_init(struct mtd_info *mtd)
switch (xnand->ecc_mode) {
case NAND_ECC_HW:
- if (mtd->writesize > 2048) {
+ if ((mtd->writesize > 2048) || ((ondie_ecc_state) &&
+ (mtd->oobsize != 64))) {
pr_warn("hardware ECC not possible\n");
return -ENOTSUPP;
}
nand_chip->ecc.mode = NAND_ECC_HW;
+ if (ondie_ecc_state) {
+ /* Bypass the controller ECC block */
+ pl353_smc_set_ecc_mode(PL353_SMC_ECCMODE_BYPASS);
+ nand_chip->ecc.bytes = 0;
+ nand_chip->ecc.layout = &ondie_nand_oob_64;
+ nand_chip->ecc.read_page = pl353_nand_read_page_raw;
+ nand_chip->ecc.write_page = pl353_nand_write_page_raw;
+ nand_chip->ecc.size = mtd->writesize;
+ /*
+ * On-Die ECC spare bytes offset 8 is used for ECC codes
+ * Use the BBT pattern descriptors
+ */
+ nand_chip->bbt_td = &bbt_main_descr;
+ nand_chip->bbt_md = &bbt_mirror_descr;
+ } else {
nand_chip->ecc.calculate = pl353_nand_calculate_hwecc;
nand_chip->ecc.correct = pl353_nand_correct_data;
nand_chip->ecc.hwctl = NULL;
@@ -852,13 +969,17 @@ static int pl353_nand_ecc_init(struct mtd_info *mtd)
nand_chip->ecc.write_page = pl353_nand_write_page_hwecc;
pl353_smc_set_ecc_pg_size(mtd->writesize);
pl353_smc_set_ecc_mode(PL353_SMC_ECCMODE_APB);
- /* Hardware ECC generates 3 bytes ECC code for each 512 bytes */
+ /*
+ * Hardware ECC generates 3 bytes ECC code for each
+ * 512 bytes
+ */
nand_chip->ecc.bytes = 3;
if (mtd->oobsize == 16)
nand_chip->ecc.layout = &nand_oob_16;
else
nand_chip->ecc.layout = &nand_oob_64;
+ }
break;
case NAND_ECC_SOFT:
@@ -900,6 +1021,7 @@ static int pl353_nand_probe(struct platform_device *pdev)
struct nand_chip *nand_chip;
struct resource *res;
struct mtd_part_parser_data ppdata;
+ int ondie_ecc_state;
xnand = devm_kzalloc(&pdev->dev, sizeof(*xnand), GFP_KERNEL);
if (!xnand)
@@ -942,6 +1064,7 @@ static int pl353_nand_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, xnand);
+ ondie_ecc_state = pl353_nand_detect_ondie_ecc(mtd);
/* first scan to find the device and get the page size */
if (nand_scan_ident(mtd, 1, NULL)) {
dev_err(&pdev->dev, "nand_scan_ident for NAND failed\n");
@@ -952,7 +1075,7 @@ static int pl353_nand_probe(struct platform_device *pdev)
if (xnand->ecc_mode < 0)
xnand->ecc_mode = NAND_ECC_HW;
- if (pl353_nand_ecc_init(mtd))
+ if (pl353_nand_ecc_init(mtd, ondie_ecc_state))
return -ENOTSUPP;
if (nand_chip->options & NAND_BUSWIDTH_16)
--
1.7.4
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