mtd: nand: sunxi: move some ECC related operations to their own functions

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>

diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c
index 8be3dba..c20bf59 100644 (file)
--- a/drivers/mtd/nand/sunxi_nand.c
+++ b/drivers/mtd/nand/sunxi_nand.c
@@ -775,6 +775,94 @@ 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,
@@ -786,7 +874,7 @@ 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)
@@ -812,27 +900,11 @@ 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.
@@ -840,35 +912,32 @@ 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;
 }
 
@@ -897,11 +966,6 @@ 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,
@@ -918,19 +982,6 @@ 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);
 
@@ -939,6 +990,8 @@ 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);