summaryrefslogtreecommitdiff
path: root/drivers/mtd/nand/mxc_nand.c
diff options
context:
space:
mode:
authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-09-08 01:01:14 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-09-08 01:01:14 -0300
commite5fd91f1ef340da553f7a79da9540c3db711c937 (patch)
treeb11842027dc6641da63f4bcc524f8678263304a3 /drivers/mtd/nand/mxc_nand.c
parent2a9b0348e685a63d97486f6749622b61e9e3292f (diff)
Linux-libre 4.2-gnu
Diffstat (limited to 'drivers/mtd/nand/mxc_nand.c')
-rw-r--r--drivers/mtd/nand/mxc_nand.c112
1 files changed, 95 insertions, 17 deletions
diff --git a/drivers/mtd/nand/mxc_nand.c b/drivers/mtd/nand/mxc_nand.c
index 372e0e38f..2426db88d 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))