sf: Add flag status register polling support
Flag status register polling is required for micron 512Mb flash
devices onwards, for performing erase/program operations.
Like polling for WIP(Write-In-Progress) bit in read status register,
spi_flash_cmd_wait_ready will poll for PEC(Program-Erase-Control)
bit in flag status register.
Signed-off-by: Jagannadha Sutradharudu Teki <jaganna@xilinx.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/mtd/spi/spi_flash.c b/drivers/mtd/spi/spi_flash.c
index cca02d1..6ce82c1 100644
--- a/drivers/mtd/spi/spi_flash.c
+++ b/drivers/mtd/spi/spi_flash.c
@@ -200,12 +200,19 @@
unsigned long timebase;
int ret;
u8 status;
+ u8 check_status = 0x0;
u8 poll_bit = STATUS_WIP;
- u8 cmd = CMD_READ_STATUS;
+ u8 cmd = flash->poll_cmd;
+
+ if (cmd == CMD_FLAG_STATUS) {
+ poll_bit = STATUS_PEC;
+ check_status = poll_bit;
+ }
ret = spi_xfer(spi, 8, &cmd, NULL, SPI_XFER_BEGIN);
if (ret) {
- debug("SF: Failed to send command %02x: %d\n", cmd, ret);
+ debug("SF: fail to read %s status register\n",
+ cmd == CMD_READ_STATUS ? "read" : "flag");
return ret;
}
@@ -217,14 +224,14 @@
if (ret)
return -1;
- if ((status & poll_bit) == 0)
+ if ((status & poll_bit) == check_status)
break;
} while (get_timer(timebase) < timeout);
spi_xfer(spi, 0, NULL, NULL, SPI_XFER_END);
- if ((status & poll_bit) == 0)
+ if ((status & poll_bit) == check_status)
return 0;
/* Timed out */
@@ -584,6 +591,7 @@
/* Set up some basic fields - caller will sort out sizes */
flash->spi = spi;
flash->name = name;
+ flash->poll_cmd = CMD_READ_STATUS;
flash->read = spi_flash_cmd_read_fast;
flash->write = spi_flash_cmd_write_multi;