[U-Boot] [PATCH 4/4] ARM: at91: atmel_nand: add code to check the ONFI parameter ECC requirement
Josh Wu
josh.wu at atmel.com
Fri Jun 14 13:20:42 CEST 2013
1. if CONFIG_SYS_NAND_ONFI_DETECTION is defined, driver will check NAND flash's
ecc minimum requirement in ONFI parameter.
a) if CONFIG_PMECC_CAP, CONFIG_PMECC_SECTOR_SIZE are defined. then use it.
Driver will display a WARNING if the values are different from ONFI
parameters.
b) if CONFIG_PMECC_CAP, CONFIG_PMECC_SECTOR_SIZE are not defined, then use
the value from ONFI parameters.
* If ONFI ECC parameters are in ONFI extended parameter page, since we
are not support it, so assume the minimum ecc requirement is 2 bits
in 512 bytes.
* For non-ONFI support nand flash, also assume the minimum ecc
requirement is 2 bits in 512 bytes.
2. if CONFIG_SYS_NAND_ONFI_DETECTION is not defined, just use CONFIG_PMECC_CAP
and CONFIG_PMECC_SECTOR_SIZE.
Signed-off-by: Josh Wu <josh.wu at atmel.com>
---
drivers/mtd/nand/atmel_nand.c | 128 ++++++++++++++++++++++++++++++++++++++++-
1 file changed, 126 insertions(+), 2 deletions(-)
diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c
index 89d4f6a..44d58e0 100644
--- a/drivers/mtd/nand/atmel_nand.c
+++ b/drivers/mtd/nand/atmel_nand.c
@@ -679,6 +679,98 @@ static void atmel_pmecc_core_init(struct mtd_info *mtd)
pmecc_writel(host->pmecc, ctrl, PMECC_CTRL_ENABLE);
}
+#ifdef CONFIG_SYS_NAND_ONFI_DETECTION
+/*
+ * get_onfi_ecc_param - Get ECC requirement from ONFI parameters
+ * @ecc_bits: store the ONFI ECC correct bits capbility
+ * @sector_size: in how many bytes that ONFI require to correct @ecc_bits
+ *
+ * Returns -1 if ONFI parameters is not supported. In this case @ecc_bits,
+ * @sector_size are initialize to 0.
+ * Return 0 if success to get the ECC requirement.
+ */
+static int get_onfi_ecc_param(struct nand_chip *chip,
+ int *ecc_bits, int *sector_size)
+{
+ *ecc_bits = *sector_size = 0;
+
+ if (chip->onfi_params.ecc_bits == 0xff)
+ /* TODO: the sector_size and ecc_bits need to be find in
+ * extended ecc parameter, currently we don't support it.
+ */
+ return -1;
+
+ *ecc_bits = chip->onfi_params.ecc_bits;
+
+ /* The default sector size (ecc codeword size) is 512 */
+ *sector_size = 512;
+
+ return 0;
+}
+
+/*
+ * pmecc_choose_ecc - Get ecc requirement from ONFI parameters. If
+ * pmecc_corr_cap or pmecc_sector_size is 0, then set it as
+ * ONFI ECC parameters.
+ * @host: point to an atmel_nand_host structure.
+ * if host->pmecc_corr_cap is 0 then set it as the ONFI ecc_bits.
+ * if host->pmecc_sector_size is 0 then set it as the ONFI sector_size.
+ * @chip: point to an nand_chip structure.
+ * @cap: store the ONFI ECC correct bits capbility
+ * @sector_size: in how many bytes that ONFI require to correct @ecc_bits
+ *
+ * Return 0 if success. otherwise return the error code.
+ */
+static int pmecc_choose_ecc(struct atmel_nand_host *host,
+ struct nand_chip *chip,
+ int *cap, int *sector_size)
+{
+ /* Get ECC requirement from ONFI parameters */
+ *cap = *sector_size = 0;
+ if (chip->onfi_version) {
+ if (!get_onfi_ecc_param(chip, cap, sector_size))
+ MTDDEBUG(MTD_DEBUG_LEVEL1, "ONFI params, minimum required ECC: %d bits in %d bytes\n",
+ *cap, *sector_size);
+ else
+ printk(KERN_WARNING "NAND chip ECC reqirement is in Extended ONFI parameter, we don't support yet.\n");
+ } else {
+ printk(KERN_WARNING "NAND chip is not ONFI compliant, assume ecc_bits is 2 in 512 bytes");
+ }
+ if (*cap == 0 && *sector_size == 0) {
+ /* Non-ONFI compliant or use extended ONFI parameters */
+ *cap = 2;
+ *sector_size = 512;
+ }
+
+ /* If head file doesn't specify then use the one in ONFI parameters */
+ if (host->pmecc_corr_cap == 0) {
+ /* use the most fitable ecc bits (the near bigger one ) */
+ if (*cap <= 2)
+ host->pmecc_corr_cap = 2;
+ else if (*cap <= 4)
+ host->pmecc_corr_cap = 4;
+ else if (*cap < 8)
+ host->pmecc_corr_cap = 8;
+ else if (*cap < 12)
+ host->pmecc_corr_cap = 12;
+ else if (*cap < 24)
+ host->pmecc_corr_cap = 24;
+ else
+ return -EINVAL;
+ }
+ if (host->pmecc_sector_size == 0) {
+ /* use the most fitable sector size (the near smaller one ) */
+ if (*sector_size >= 1024)
+ host->pmecc_sector_size = 1024;
+ else if (*sector_size >= 512)
+ host->pmecc_sector_size = 512;
+ else
+ return -EINVAL;
+ }
+ return 0;
+}
+#endif
+
static int atmel_pmecc_nand_init_params(struct nand_chip *nand,
struct mtd_info *mtd)
{
@@ -692,8 +784,40 @@ static int atmel_pmecc_nand_init_params(struct nand_chip *nand,
nand->ecc.correct = NULL;
nand->ecc.hwctl = NULL;
- cap = host->pmecc_corr_cap = CONFIG_PMECC_CAP;
- sector_size = host->pmecc_sector_size = CONFIG_PMECC_SECTOR_SIZE;
+#ifdef CONFIG_SYS_NAND_ONFI_DETECTION
+ host->pmecc_corr_cap = host->pmecc_sector_size = 0;
+
+#ifdef CONFIG_PMECC_CAP
+ host->pmecc_corr_cap = CONFIG_PMECC_CAP;
+#endif
+#ifdef CONFIG_PMECC_SECTOR_SIZE
+ host->pmecc_sector_size = CONFIG_PMECC_SECTOR_SIZE;
+#endif
+ /* Get ECC requirement of ONFI parameters. And if CONFIG_PMECC_CAP or
+ * CONFIG_PMECC_SECTOR_SIZE not defined, then use ecc_bits, sector_size
+ * from ONFI.
+ */
+ if (pmecc_choose_ecc(host, nand, &cap, §or_size)) {
+ printk(KERN_WARNING "The NAND flash's ECC requirement are not support!");
+ return -EINVAL;
+ }
+
+ if (cap > host->pmecc_corr_cap)
+ printk(KERN_WARNING "WARNING: Using different ecc correct bits(%d bit) from Nand ONFI ECC reqirement (%d bit).\n",
+ host->pmecc_corr_cap, cap);
+ if (sector_size < host->pmecc_sector_size)
+ printk(KERN_WARNING "WARNING: Using different ecc correct sector size (%d bytes) from Nand ONFI ECC reqirement (%d bytes).\n",
+ host->pmecc_sector_size, sector_size);
+#else /* CONFIG_SYS_NAND_ONFI_DETECTION */
+ host->pmecc_corr_cap = CONFIG_PMECC_CAP;
+ host->pmecc_sector_size = CONFIG_PMECC_SECTOR_SIZE;
+#endif
+
+ cap = host->pmecc_corr_cap;
+ sector_size = host->pmecc_sector_size;
+
+ /* TODO: need check whether cap & sector_size is validate */
+
if (host->pmecc_sector_size == 512)
host->pmecc_index_table_offset = ATMEL_PMECC_INDEX_OFFSET_512;
else
--
1.7.9.5
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