[PATCH 1/7] mtd: nand: sunxi: move some ECC related operations to their own functions

Boris Brezillon
2016-03-08T11:15:43Z

In order to support DMA operations in a clean way we need to extract some
of the logic coded in sunxi_nfc_hw_ecc_read/write_page() into their own
function.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
---
drivers/mtd/nand/sunxi_nand.c | 163 ++++++++++++++++++++++++++++--------------
1 file changed, 108 insertions(+), 55 deletions(-)

diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c
index 0616f3b..90c121d 100644
--- a/drivers/mtd/nand/sunxi_nand.c
+++ b/drivers/mtd/nand/sunxi_nand.c
@@ -776,6 +776,94 @@ static inline void sunxi_nfc_user_data_to_buf(u32 user_data, u8 *buf)
buf[3] = user_data >> 24;
}

+static inline u32 sunxi_nfc_buf_to_user_data(const u8 *buf)
+{
+ return buf[0] | (buf[1] << 8) | (buf[2] << 16) | (buf[3] << 24);
+}
+
+static void sunxi_nfc_hw_ecc_get_prot_oob_bytes(struct mtd_info *mtd, u8 *oob,
+ int step, bool bbm, int page)
+{
+ struct nand_chip *nand = mtd_to_nand(mtd);
+ struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
+
+ sunxi_nfc_user_data_to_buf(readl(nfc->regs + NFC_REG_USER_DATA(step)),
+ oob);
+
+ /* De-randomize the Bad Block Marker. */
+ if (bbm && (nand->options & NAND_NEED_SCRAMBLING))
+ sunxi_nfc_randomize_bbm(mtd, page, oob);
+}
+
+static void sunxi_nfc_hw_ecc_set_prot_oob_bytes(struct mtd_info *mtd,
+ const u8 *oob, int step,
+ bool bbm, int page)
+{
+ struct nand_chip *nand = mtd_to_nand(mtd);
+ struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
+ u8 user_data[4];
+
+ /* Randomize the Bad Block Marker. */
+ if (bbm && (nand->options & NAND_NEED_SCRAMBLING)) {
+ memcpy(user_data, oob, sizeof(user_data));
+ sunxi_nfc_randomize_bbm(mtd, page, user_data);
+ oob = user_data;
+ }
+
+ writel(sunxi_nfc_buf_to_user_data(oob),
+ nfc->regs + NFC_REG_USER_DATA(step));
+}
+
+static void sunxi_nfc_hw_ecc_update_stats(struct mtd_info *mtd,
+ unsigned int *max_bitflips, int ret)
+{
+ if (ret < 0) {
+ mtd->ecc_stats.failed++;
+ } else {
+ mtd->ecc_stats.corrected += ret;
+ *max_bitflips = max_t(unsigned int, *max_bitflips, ret);
+ }
+}
+
+static int sunxi_nfc_hw_ecc_correct(struct mtd_info *mtd, u8 *data, u8 *oob,
+ int step, bool *erased)
+{
+ struct nand_chip *nand = mtd_to_nand(mtd);
+ struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
+ struct nand_ecc_ctrl *ecc = &nand->ecc;
+ u32 status, tmp;
+
+ *erased = false;
+
+ status = readl(nfc->regs + NFC_REG_ECC_ST);
+
+ if (status & NFC_ECC_ERR(step))
+ return -EBADMSG;
+
+ if (status & NFC_ECC_PAT_FOUND(step)) {
+ u8 pattern;
+
+ if (unlikely(!(readl(nfc->regs + NFC_REG_PAT_ID) & 0x1))) {
+ pattern = 0x0;
+ } else {
+ pattern = 0xff;
+ *erased = true;
+ }
+
+ if (data)
+ memset(data, pattern, ecc->size);
+
+ if (oob)
+ memset(oob, pattern, ecc->bytes + 4);
+
+ return 0;
+ }
+
+ tmp = readl(nfc->regs + NFC_REG_ECC_ERR_CNT(step));
+
+ return NFC_ECC_ERR_CNT(step, tmp);
+}
+
static int sunxi_nfc_hw_ecc_read_chunk(struct mtd_info *mtd,
u8 *data, int data_off,
u8 *oob, int oob_off,
@@ -787,7 +875,7 @@ static int sunxi_nfc_hw_ecc_read_chunk(struct mtd_info *mtd,
struct sunxi_nfc *nfc = to_sunxi_nfc(nand->controller);
struct nand_ecc_ctrl *ecc = &nand->ecc;
int raw_mode = 0;
- u32 status;
+ bool erased;
int ret;

if (*cur_off != data_off)
@@ -813,27 +901,11 @@ static int sunxi_nfc_hw_ecc_read_chunk(struct mtd_info *mtd,

*cur_off = oob_off + ecc->bytes + 4;

- status = readl(nfc->regs + NFC_REG_ECC_ST);
- if (status & NFC_ECC_PAT_FOUND(0)) {
- u8 pattern = 0xff;
-
- if (unlikely(!(readl(nfc->regs + NFC_REG_PAT_ID) & 0x1)))
- pattern = 0x0;
-
- memset(data, pattern, ecc->size);
- memset(oob, pattern, ecc->bytes + 4);
-
+ ret = sunxi_nfc_hw_ecc_correct(mtd, data, oob, 0, &erased);
+ if (erased)
return 1;
- }
-
- ret = NFC_ECC_ERR_CNT(0, readl(nfc->regs + NFC_REG_ECC_ERR_CNT(0)));
-
- memcpy_fromio(data, nfc->regs + NFC_RAM0_BASE, ecc->size);

- nand->cmdfunc(mtd, NAND_CMD_RNDOUT, oob_off, -1);
- sunxi_nfc_randomizer_read_buf(mtd, oob, ecc->bytes + 4, true, page);
-
- if (status & NFC_ECC_ERR(0)) {
+ if (ret < 0) {
/*
* Re-read the data with the randomizer disabled to identify
* bitflips in erased pages.
@@ -841,35 +913,32 @@ static int sunxi_nfc_hw_ecc_read_chunk(struct mtd_info *mtd,
if (nand->options & NAND_NEED_SCRAMBLING) {
nand->cmdfunc(mtd, NAND_CMD_RNDOUT, data_off, -1);
nand->read_buf(mtd, data, ecc->size);
- nand->cmdfunc(mtd, NAND_CMD_RNDOUT, oob_off, -1);
- nand->read_buf(mtd, oob, ecc->bytes + 4);
+ } else {
+ memcpy_fromio(data, nfc->regs + NFC_RAM0_BASE,
+ ecc->size);
}

+ nand->cmdfunc(mtd, NAND_CMD_RNDOUT, oob_off, -1);
+ nand->read_buf(mtd, oob, ecc->bytes + 4);
+
ret = nand_check_erased_ecc_chunk(data, ecc->size,
oob, ecc->bytes + 4,
NULL, 0, ecc->strength);
if (ret >= 0)
raw_mode = 1;
} else {
- /*
- * The engine protects 4 bytes of OOB data per chunk.
- * Retrieve the corrected OOB bytes.
- */
- sunxi_nfc_user_data_to_buf(readl(nfc->regs + NFC_REG_USER_DATA(0)),
- oob);
+ memcpy_fromio(data, nfc->regs + NFC_RAM0_BASE, ecc->size);

- /* De-randomize the Bad Block Marker. */
- if (bbm && nand->options & NAND_NEED_SCRAMBLING)
- sunxi_nfc_randomize_bbm(mtd, page, oob);
- }
+ nand->cmdfunc(mtd, NAND_CMD_RNDOUT, oob_off, -1);
+ sunxi_nfc_randomizer_read_buf(mtd, oob, ecc->bytes + 4,
+ true, page);

- if (ret < 0) {
- mtd->ecc_stats.failed++;
- } else {
- mtd->ecc_stats.corrected += ret;
- *max_bitflips = max_t(unsigned int, *max_bitflips, ret);
+ sunxi_nfc_hw_ecc_get_prot_oob_bytes(mtd, oob, 0,
+ bbm, page);
}

+ sunxi_nfc_hw_ecc_update_stats(mtd, max_bitflips, ret);
+
return raw_mode;
}

@@ -898,11 +967,6 @@ static void sunxi_nfc_hw_ecc_read_extra_oob(struct mtd_info *mtd,
*cur_off = mtd->oobsize + mtd->writesize;
}

-static inline u32 sunxi_nfc_buf_to_user_data(const u8 *buf)
-{
- return buf[0] | (buf[1] << 8) | (buf[2] << 16) | (buf[3] << 24);
-}
-
static int sunxi_nfc_hw_ecc_write_chunk(struct mtd_info *mtd,
const u8 *data, int data_off,
const u8 *oob, int oob_off,
@@ -919,19 +983,6 @@ static int sunxi_nfc_hw_ecc_write_chunk(struct mtd_info *mtd,

sunxi_nfc_randomizer_write_buf(mtd, data, ecc->size, false, page);

- /* Fill OOB data in */
- if ((nand->options & NAND_NEED_SCRAMBLING) && bbm) {
- u8 user_data[4];
-
- memcpy(user_data, oob, 4);
- sunxi_nfc_randomize_bbm(mtd, page, user_data);
- writel(sunxi_nfc_buf_to_user_data(user_data),
- nfc->regs + NFC_REG_USER_DATA(0));
- } else {
- writel(sunxi_nfc_buf_to_user_data(oob),
- nfc->regs + NFC_REG_USER_DATA(0));
- }
-
if (data_off + ecc->size != oob_off)
nand->cmdfunc(mtd, NAND_CMD_RNDIN, oob_off, -1);

@@ -940,6 +991,8 @@ static int sunxi_nfc_hw_ecc_write_chunk(struct mtd_info *mtd,
return ret;

sunxi_nfc_randomizer_enable(mtd);
+ sunxi_nfc_hw_ecc_set_prot_oob_bytes(mtd, oob, 0, bbm, page);
+
writel(NFC_DATA_TRANS | NFC_DATA_SWAP_METHOD |
NFC_ACCESS_DIR | NFC_ECC_OP,
nfc->regs + NFC_REG_CMD);
--
2.1.4