mtd: spi-nor: Changed spi-nor.c file for stacked mode support

Added stacked configuration support to spi-nor

Signed-off-by: Anurag Kumar Vulisha <anuragku@xilinx.com>
Reviewed-by: Harini Katakam <harinik@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index 1080b97dfea5504e57a0589967780d419308b0ed..fce0fd99c64bccdaa5f1f47e3e8cad5a34d0efb8 100644 (file)
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -1018,6 +1018,7 @@ static int spi_nor_read_ext(struct mtd_info *mtd, loff_t from, size_t len,
        u32 read_count = 0;
        u32 rem_bank_len = 0;
        u8 bank = 0;
+       u8 stack_shift = 0;
        int ret;
 
 #define OFFSET_16_MB 0x1000000
@@ -1029,25 +1030,18 @@ static int spi_nor_read_ext(struct mtd_info *mtd, loff_t from, size_t len,
                return ret;
        if (nor->isparallel)
                nor->spi->master->flags |= SPI_DATA_STRIPE;
-       if (nor->addr_width == 4) {
-               /* Wait till previous write/erase is done. */
-               ret = spi_nor_wait_till_ready(nor);
-               if (ret)
-                       goto read_err;
-               /* Die cross over issue is not handled */
-               if (nor->isparallel)
-                       from /= 2;
-               ret = nor->read(nor, from, len, retlen, buf);
-               goto read_err;
-       }
+
        while (len) {
-               bank = addr / (OFFSET_16_MB << nor->shift);
-               rem_bank_len = ((OFFSET_16_MB << nor->shift) * (bank + 1)) -
-                               addr;
+               if (nor->addr_width == 3) {
+                       bank = addr / (OFFSET_16_MB << nor->shift);
+                       rem_bank_len = ((OFFSET_16_MB << nor->shift) *
+                                                       (bank + 1)) - addr;
+               }
                offset = addr;
                if (nor->isparallel == 1)
                        offset /= 2;
                if (nor->isstacked == 1) {
+                       stack_shift = 1;
                        if (offset >= (nor->mtd->size / 2)) {
                                offset = offset - (nor->mtd->size / 2);
                                nor->spi->master->flags |= SPI_MASTER_U_PAGE;
@@ -1055,12 +1049,23 @@ static int spi_nor_read_ext(struct mtd_info *mtd, loff_t from, size_t len,
                                nor->spi->master->flags &= ~SPI_MASTER_U_PAGE;
                        }
                }
-               write_ear(nor, offset);
+               /* Die cross over issue is not handled */
+               if (nor->addr_width == 4) {
+                       rem_bank_len = (nor->mtd->size >> stack_shift) -
+                                       (offset << nor->shift);
+               }
+               if (nor->addr_width == 3)
+                       write_ear(nor, offset);
                if (len < rem_bank_len)
                        read_len = len;
                else
                        read_len = rem_bank_len;
 
+               /* Wait till previous write/erase is done. */
+               ret = spi_nor_wait_till_ready(nor);
+               if (ret)
+                       goto read_err;
+
                ret = spi_nor_read(mtd, offset, read_len, &actual_len, buf);
                if (ret)
                        return ret;
@@ -1206,6 +1211,7 @@ static int spi_nor_write_ext(struct mtd_info *mtd, loff_t to, size_t len,
        u32 write_count = 0;
        u32 rem_bank_len = 0;
        u8 bank = 0;
+       u8 stack_shift = 0;
        int ret;
 
 #define OFFSET_16_MB 0x1000000
@@ -1217,19 +1223,18 @@ static int spi_nor_write_ext(struct mtd_info *mtd, loff_t to, size_t len,
                return ret;
        if (nor->isparallel)
                nor->spi->master->flags |= SPI_DATA_STRIPE;
-       if (nor->addr_width == 4) {
-               /* Die cross over issue is not handled */
-               ret = spi_nor_write(mtd, offset, len, retlen, buf);
-               goto write_err;
-       }
+
        while (len) {
                actual_len = 0;
-               bank = addr / (OFFSET_16_MB << nor->shift);
-               rem_bank_len = ((OFFSET_16_MB << nor->shift) * (bank + 1)) -
-                               addr;
+               if (nor->addr_width == 3) {
+                       bank = addr / (OFFSET_16_MB << nor->shift);
+                       rem_bank_len = ((OFFSET_16_MB << nor->shift) *
+                                                       (bank + 1)) - addr;
+               }
                offset = addr;
 
                if (nor->isstacked == 1) {
+                       stack_shift = 1;
                        if (offset >= (nor->mtd->size / 2)) {
                                offset = offset - (nor->mtd->size / 2);
                                nor->spi->master->flags |= SPI_MASTER_U_PAGE;
@@ -1237,7 +1242,11 @@ static int spi_nor_write_ext(struct mtd_info *mtd, loff_t to, size_t len,
                                nor->spi->master->flags &= ~SPI_MASTER_U_PAGE;
                        }
                }
-               write_ear(nor, (offset >> nor->shift));
+               /* Die cross over issue is not handled */
+               if (nor->addr_width == 4)
+                       rem_bank_len = (nor->mtd->size >> stack_shift) - offset;
+               if (nor->addr_width == 3)
+                       write_ear(nor, (offset >> nor->shift));
                if (len < rem_bank_len)
                        write_len = len;
                else
@@ -1466,10 +1475,25 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode)
                                        nor->isstacked = 1;
                                        nor->isparallel = 0;
 #else
-                                       /* single */
-                                       nor->shift = 0;
-                                       nor->isstacked = 0;
-                                       nor->isparallel = 0;
+                                       u32 is_stacked;
+                                       if (of_property_read_u32(np_spi,
+                                                       "is-stacked",
+                                                       &is_stacked) < 0) {
+                                               is_stacked = 0;
+                                       }
+                                       if (is_stacked) {
+                                               /* dual stacked */
+                                               nor->shift = 0;
+                                               mtd->size <<= 1;
+                                               info->n_sectors <<= 1;
+                                               nor->isstacked = 1;
+                                               nor->isparallel = 0;
+                                       } else {
+                                               /* single */
+                                               nor->shift = 0;
+                                               nor->isstacked = 0;
+                                               nor->isparallel = 0;
+                                       }
 #endif
                                }
                        }
@@ -1627,6 +1651,11 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode)
                        mtd->erasesize = info->sector_size;
                } else
                        set_4byte(nor, info, 1);
+                       if (nor->isstacked) {
+                               nor->spi->master->flags |= SPI_MASTER_U_PAGE;
+                               set_4byte(nor, info, 1);
+                               nor->spi->master->flags &= ~SPI_MASTER_U_PAGE;
+                       }
 #ifdef CONFIG_OF
                }
 #endif