[U-Boot] [PATCH] cfi_flash driver - Add delay after reset command

[U-Boot] [PATCH] cfi_flash driver - Add delay after reset command

[Aaron Williams]

I ran into a problem where the reset was failing except when I enabled
debugging support.  After talking with Garret Swalling at Spansion I
was told that the GL-N series of devices require a 500ns wait for the
reset to complete.  The below patch adds a 1us delay after all reset
commands.

-Aaron Williams

Signed-off-by: Aaron Williams <aaron.williams@caviumnetworks.com>
---
 drivers/mtd/cfi_flash.c |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/drivers/mtd/cfi_flash.c b/drivers/mtd/cfi_flash.c
index 9ee639e..4bc01f7 100644
--- a/drivers/mtd/cfi_flash.c
+++ b/drivers/mtd/cfi_flash.c
@@ -586,6 +586,7 @@ static int flash_status_check (flash_info_t * info, flash_sect_t sector,
 				prompt, info->start[sector],
 				flash_read_long (info, sector, 0));
 			flash_write_cmd (info, sector, 0, info->cmd_reset);
+			udelay(1);
 			return ERR_TIMOUT;
 		}
 		udelay (1);		/* also triggers watchdog */
@@ -633,6 +634,7 @@ static int flash_full_status_check (flash_info_t * info, flash_sect_t sector,
 				puts ("Vpp Low Error.\n");
 		}
 		flash_write_cmd (info, sector, 0, info->cmd_reset);
+		udelay(1);
 		break;
 	default:
 		break;
@@ -1496,6 +1498,7 @@ void flash_read_user_serial (flash_info_t * info, void *buffer, int offset,
 	flash_write_cmd (info, 0, 0, FLASH_CMD_READ_ID);
 	memcpy (dst, src + offset, len);
 	flash_write_cmd (info, 0, 0, info->cmd_reset);
+	udelay(1);
 	flash_unmap(info, 0, FLASH_OFFSET_USER_PROTECTION, src);
 }
 
@@ -1511,6 +1514,7 @@ void flash_read_factory_serial (flash_info_t * info, void *buffer, int offset,
 	flash_write_cmd (info, 0, 0, FLASH_CMD_READ_ID);
 	memcpy (buffer, src + offset, len);
 	flash_write_cmd (info, 0, 0, info->cmd_reset);
+	udelay(1);
 	flash_unmap(info, 0, FLASH_OFFSET_INTEL_PROTECTION, src);
 }
 
@@ -1542,6 +1546,7 @@ static void cfi_reverse_geometry(struct cfi_qry *qry)
 static void cmdset_intel_read_jedec_ids(flash_info_t *info)
 {
 	flash_write_cmd(info, 0, 0, FLASH_CMD_RESET);
+	udelay(1);
 	flash_write_cmd(info, 0, 0, FLASH_CMD_READ_ID);
 	udelay(1000); /* some flash are slow to respond */
 	info->manufacturer_id = flash_read_uchar (info,
@@ -1610,6 +1615,7 @@ static void cmdset_amd_read_jedec_ids(flash_info_t *info)
 		break;
 	}
 	flash_write_cmd(info, 0, 0, AMD_CMD_RESET);
+	udelay(1);
 }
 
 static int cmdset_amd_init(flash_info_t *info, struct cfi_qry *qry)
@@ -1736,6 +1742,7 @@ void __flash_cmd_reset(flash_info_t *info)
 	 * that AMD flash roms ignore the Intel command.
 	 */
 	flash_write_cmd(info, 0, 0, AMD_CMD_RESET);
+	udelay(1);
 	flash_write_cmd(info, 0, 0, FLASH_CMD_RESET);
 }
 void flash_cmd_reset(flash_info_t *info)
-- 
1.7.3.4

[U-Boot] [PATCH] cfi_flash driver - Add delay after reset command

[Stefan Roese]

On Tuesday 12 April 2011 09:59:04 Aaron Williams wrote:
> I ran into a problem where the reset was failing except when I enabled
> debugging support.  After talking with Garret Swalling at Spansion I
> was told that the GL-N series of devices require a 500ns wait for the
> reset to complete.  The below patch adds a 1us delay after all reset
> commands.

Applied to u-boot-cfi-flash/master. Thanks.

Cheers,
Stefan

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