sf: Add dual memories support - DUAL_STACKED
This patch added support for accessing dual memories in
stacked connection with single chipselect line from controller.
For more info - see doc/SPI/README.dual-flash
Signed-off-by: Jagannadha Sutradharudu Teki <jaganna@xilinx.com>
diff --git a/drivers/mtd/spi/sf_ops.c b/drivers/mtd/spi/sf_ops.c
index 7ae9582..e877858 100644
--- a/drivers/mtd/spi/sf_ops.c
+++ b/drivers/mtd/spi/sf_ops.c
@@ -131,10 +131,28 @@
}
#endif
+static void spi_flash_dual_flash(struct spi_flash *flash, u32 *addr)
+{
+ switch (flash->dual_flash) {
+ case SF_DUAL_STACKED_FLASH:
+ if (*addr >= (flash->size >> 1)) {
+ *addr -= flash->size >> 1;
+ flash->spi->flags |= SPI_XFER_U_PAGE;
+ } else {
+ flash->spi->flags &= ~SPI_XFER_U_PAGE;
+ }
+ break;
+ default:
+ debug("SF: Unsupported dual_flash=%d\n", flash->dual_flash);
+ break;
+ }
+}
+
int spi_flash_cmd_wait_ready(struct spi_flash *flash, unsigned long timeout)
{
struct spi_slave *spi = flash->spi;
unsigned long timebase;
+ unsigned long flags = SPI_XFER_BEGIN;
int ret;
u8 status;
u8 check_status = 0x0;
@@ -146,7 +164,10 @@
check_status = poll_bit;
}
+ if (spi->flags & SPI_XFER_U_PAGE)
+ flags |= SPI_XFER_U_PAGE;
+
- ret = spi_xfer(spi, 8, &cmd, NULL, SPI_XFER_BEGIN);
+ ret = spi_xfer(spi, 8, &cmd, NULL, flags);
if (ret) {
debug("SF: fail to read %s status register\n",
cmd == CMD_READ_STATUS ? "read" : "flag");
@@ -219,7 +240,7 @@
int spi_flash_cmd_erase_ops(struct spi_flash *flash, u32 offset, size_t len)
{
- u32 erase_size;
+ u32 erase_size, erase_addr;
u8 cmd[SPI_FLASH_CMD_LEN];
int ret = -1;
@@ -231,15 +252,20 @@
cmd[0] = flash->erase_cmd;
while (len) {
+ erase_addr = offset;
+
+ if (flash->dual_flash > SF_SINGLE_FLASH)
+ spi_flash_dual_flash(flash, &erase_addr);
+
#ifdef CONFIG_SPI_FLASH_BAR
- ret = spi_flash_bank(flash, offset);
+ ret = spi_flash_bank(flash, erase_addr);
if (ret < 0)
return ret;
#endif
- spi_flash_addr(offset, cmd);
+ spi_flash_addr(erase_addr, cmd);
debug("SF: erase %2x %2x %2x %2x (%x)\n", cmd[0], cmd[1],
- cmd[2], cmd[3], offset);
+ cmd[2], cmd[3], erase_addr);
ret = spi_flash_write_common(flash, cmd, sizeof(cmd), NULL, 0);
if (ret < 0) {
@@ -258,6 +284,7 @@
size_t len, const void *buf)
{
unsigned long byte_addr, page_size;
+ u32 write_addr;
size_t chunk_len, actual;
u8 cmd[SPI_FLASH_CMD_LEN];
int ret = -1;
@@ -266,8 +293,13 @@
cmd[0] = flash->write_cmd;
for (actual = 0; actual < len; actual += chunk_len) {
+ write_addr = offset;
+
+ if (flash->dual_flash > SF_SINGLE_FLASH)
+ spi_flash_dual_flash(flash, &write_addr);
+
#ifdef CONFIG_SPI_FLASH_BAR
- ret = spi_flash_bank(flash, offset);
+ ret = spi_flash_bank(flash, write_addr);
if (ret < 0)
return ret;
#endif
@@ -277,7 +309,7 @@
if (flash->spi->max_write_size)
chunk_len = min(chunk_len, flash->spi->max_write_size);
- spi_flash_addr(offset, cmd);
+ spi_flash_addr(write_addr, cmd);
debug("SF: 0x%p => cmd = { 0x%02x 0x%02x%02x%02x } chunk_len = %zu\n",
buf + actual, cmd[0], cmd[1], cmd[2], cmd[3], chunk_len);
@@ -322,7 +354,7 @@
size_t len, void *data)
{
u8 *cmd, cmdsz;
- u32 remain_len, read_len;
+ u32 remain_len, read_len, read_addr;
int bank_sel = 0;
int ret = -1;
@@ -346,8 +378,13 @@
cmd[0] = flash->read_cmd;
while (len) {
+ read_addr = offset;
+
+ if (flash->dual_flash > SF_SINGLE_FLASH)
+ spi_flash_dual_flash(flash, &read_addr);
+
#ifdef CONFIG_SPI_FLASH_BAR
- bank_sel = spi_flash_bank(flash, offset);
+ bank_sel = spi_flash_bank(flash, read_addr);
if (bank_sel < 0)
return ret;
#endif
@@ -357,7 +394,7 @@
else
read_len = remain_len;
- spi_flash_addr(offset, cmd);
+ spi_flash_addr(read_addr, cmd);
ret = spi_flash_read_common(flash, cmd, cmdsz, data, read_len);
if (ret < 0) {