diff options
Diffstat (limited to 'drivers/mtd/nand/mxc_nand.c')
-rw-r--r-- | drivers/mtd/nand/mxc_nand.c | 112 |
1 files changed, 95 insertions, 17 deletions
diff --git a/drivers/mtd/nand/mxc_nand.c b/drivers/mtd/nand/mxc_nand.c index 372e0e38f59b..2426db88db36 100644 --- a/drivers/mtd/nand/mxc_nand.c +++ b/drivers/mtd/nand/mxc_nand.c @@ -189,6 +189,7 @@ struct mxc_nand_host { int clk_act; int irq; int eccsize; + int used_oobsize; int active_cs; struct completion op_completion; @@ -280,12 +281,44 @@ static void memcpy32_fromio(void *trg, const void __iomem *src, size_t size) *t++ = __raw_readl(s++); } +static void memcpy16_fromio(void *trg, const void __iomem *src, size_t size) +{ + int i; + u16 *t = trg; + const __iomem u16 *s = src; + + /* We assume that src (IO) is always 32bit aligned */ + if (PTR_ALIGN(trg, 4) == trg && IS_ALIGNED(size, 4)) { + memcpy32_fromio(trg, src, size); + return; + } + + for (i = 0; i < (size >> 1); i++) + *t++ = __raw_readw(s++); +} + static inline void memcpy32_toio(void __iomem *trg, const void *src, int size) { /* __iowrite32_copy use 32bit size values so divide by 4 */ __iowrite32_copy(trg, src, size / 4); } +static void memcpy16_toio(void __iomem *trg, const void *src, int size) +{ + int i; + __iomem u16 *t = trg; + const u16 *s = src; + + /* We assume that trg (IO) is always 32bit aligned */ + if (PTR_ALIGN(src, 4) == src && IS_ALIGNED(size, 4)) { + memcpy32_toio(trg, src, size); + return; + } + + for (i = 0; i < (size >> 1); i++) + __raw_writew(*s++, t++); +} + static int check_int_v3(struct mxc_nand_host *host) { uint32_t tmp; @@ -807,32 +840,48 @@ static void mxc_nand_select_chip_v2(struct mtd_info *mtd, int chip) } /* - * Function to transfer data to/from spare area. + * The controller splits a page into data chunks of 512 bytes + partial oob. + * There are writesize / 512 such chunks, the size of the partial oob parts is + * oobsize / #chunks rounded down to a multiple of 2. The last oob chunk then + * contains additionally the byte lost by rounding (if any). + * This function handles the needed shuffling between host->data_buf (which + * holds a page in natural order, i.e. writesize bytes data + oobsize bytes + * spare) and the NFC buffer. */ static void copy_spare(struct mtd_info *mtd, bool bfrom) { struct nand_chip *this = mtd->priv; struct mxc_nand_host *host = this->priv; - u16 i, j; - u16 n = mtd->writesize >> 9; + u16 i, oob_chunk_size; + u16 num_chunks = mtd->writesize / 512; + u8 *d = host->data_buf + mtd->writesize; u8 __iomem *s = host->spare0; - u16 t = host->devtype_data->spare_len; + u16 sparebuf_size = host->devtype_data->spare_len; - j = (mtd->oobsize / n >> 1) << 1; + /* size of oob chunk for all but possibly the last one */ + oob_chunk_size = (host->used_oobsize / num_chunks) & ~1; if (bfrom) { - for (i = 0; i < n - 1; i++) - memcpy32_fromio(d + i * j, s + i * t, j); - - /* the last section */ - memcpy32_fromio(d + i * j, s + i * t, mtd->oobsize - i * j); + for (i = 0; i < num_chunks - 1; i++) + memcpy16_fromio(d + i * oob_chunk_size, + s + i * sparebuf_size, + oob_chunk_size); + + /* the last chunk */ + memcpy16_fromio(d + i * oob_chunk_size, + s + i * sparebuf_size, + host->used_oobsize - i * oob_chunk_size); } else { - for (i = 0; i < n - 1; i++) - memcpy32_toio(&s[i * t], &d[i * j], j); - - /* the last section */ - memcpy32_toio(&s[i * t], &d[i * j], mtd->oobsize - i * j); + for (i = 0; i < num_chunks - 1; i++) + memcpy16_toio(&s[i * sparebuf_size], + &d[i * oob_chunk_size], + oob_chunk_size); + + /* the last chunk */ + memcpy16_toio(&s[oob_chunk_size * sparebuf_size], + &d[i * oob_chunk_size], + host->used_oobsize - i * oob_chunk_size); } } @@ -911,6 +960,23 @@ static int get_eccsize(struct mtd_info *mtd) return 8; } +static void ecc_8bit_layout_4k(struct nand_ecclayout *layout) +{ + int i, j; + + layout->eccbytes = 8*18; + for (i = 0; i < 8; i++) + for (j = 0; j < 18; j++) + layout->eccpos[i*18 + j] = i*26 + j + 7; + + layout->oobfree[0].offset = 2; + layout->oobfree[0].length = 4; + for (i = 1; i < 8; i++) { + layout->oobfree[i].offset = i*26; + layout->oobfree[i].length = 7; + } +} + static void preset_v1(struct mtd_info *mtd) { struct nand_chip *nand_chip = mtd->priv; @@ -1350,7 +1416,7 @@ static inline int is_imx53_nfc(struct mxc_nand_host *host) return host->devtype_data == &imx53_nand_devtype_data; } -static struct platform_device_id mxcnd_devtype[] = { +static const struct platform_device_id mxcnd_devtype[] = { { .name = "imx21-nand", .driver_data = (kernel_ulong_t) &imx21_nand_devtype_data, @@ -1587,8 +1653,20 @@ static int mxcnd_probe(struct platform_device *pdev) if (mtd->writesize == 2048) this->ecc.layout = host->devtype_data->ecclayout_2k; - else if (mtd->writesize == 4096) + else if (mtd->writesize == 4096) { this->ecc.layout = host->devtype_data->ecclayout_4k; + if (get_eccsize(mtd) == 8) + ecc_8bit_layout_4k(this->ecc.layout); + } + + /* + * Experimentation shows that i.MX NFC can only handle up to 218 oob + * bytes. Limit used_oobsize to 218 so as to not confuse copy_spare() + * into copying invalid data to/from the spare IO buffer, as this + * might cause ECC data corruption when doing sub-page write to a + * partially written page. + */ + host->used_oobsize = min(mtd->oobsize, 218U); if (this->ecc.mode == NAND_ECC_HW) { if (is_imx21_nfc(host) || is_imx27_nfc(host)) |