[U-Boot] [PATCH] driver/mtd/IFC:Wait tWB time, poll R/B before command execution

[U-Boot] [PATCH] driver/mtd/IFC:Wait tWB time, poll R/B before command execution

[Prabhakar Kushwaha]

IFC_FIR_OP_CMD0 issues command for execution without checking flash
readiness. It may cause problem if flash is not ready. Instead use
IFC_FIR_OP_CW0 which Wait for tWB time and poll R/B to return high or
time-out, before issuing command.

NAND_CMD_READID command implemention does not fulfill above requirement. So
update its programming.

Signed-off-by: Prabhakar Kushwaha <prabhakar@freescale.com>
Signed-off-by: Hemant Nautiyal <hemant.nautiyal@freescale.com>
---
Please note this patch depends upon following patch:
 "driver/mtd:IFC NAND:Initialise internal SRAM before any write"
  http://patchwork.ozlabs.org/patch/183550/
   

 drivers/mtd/nand/fsl_ifc_nand.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/mtd/nand/fsl_ifc_nand.c b/drivers/mtd/nand/fsl_ifc_nand.c
index 6619ecf..8c119e0 100644
--- a/drivers/mtd/nand/fsl_ifc_nand.c
+++ b/drivers/mtd/nand/fsl_ifc_nand.c
@@ -391,7 +391,7 @@ static void fsl_ifc_cmdfunc(struct mtd_info *mtd, unsigned int command,
 			timing = IFC_FIR_OP_RBCD;
 
 		out_be32(&ifc->ifc_nand.nand_fir0,
-				(IFC_FIR_OP_CMD0 << IFC_NAND_FIR0_OP0_SHIFT) |
+				(IFC_FIR_OP_CW0 << IFC_NAND_FIR0_OP0_SHIFT) |
 				(IFC_FIR_OP_UA  << IFC_NAND_FIR0_OP1_SHIFT) |
 				(timing << IFC_NAND_FIR0_OP2_SHIFT));
 		out_be32(&ifc->ifc_nand.nand_fcr0,
@@ -758,7 +758,7 @@ static void fsl_ifc_sram_init(void)
 
 	/* READID */
 	out_be32(&ifc->ifc_nand.nand_fir0,
-			(IFC_FIR_OP_CMD0 << IFC_NAND_FIR0_OP0_SHIFT) |
+			(IFC_FIR_OP_CW0 << IFC_NAND_FIR0_OP0_SHIFT) |
 			(IFC_FIR_OP_UA  << IFC_NAND_FIR0_OP1_SHIFT) |
 			(IFC_FIR_OP_RB << IFC_NAND_FIR0_OP2_SHIFT));
 	out_be32(&ifc->ifc_nand.nand_fcr0,
-- 
1.7.9.5

[U-Boot] driver/mtd/IFC:Wait tWB time, poll R/B before command execution

[Scott Wood]

On Wed, Nov 07, 2012 at 09:52:27PM -0000, Prabhakar Kushwaha wrote:
> IFC_FIR_OP_CMD0 issues command for execution without checking flash
> readiness. It may cause problem if flash is not ready. Instead use
> IFC_FIR_OP_CW0 which Wait for tWB time and poll R/B to return high or
> time-out, before issuing command.
> 
> NAND_CMD_READID command implemention does not fulfill above requirement. So
> update its programming.
> 
> Signed-off-by: Prabhakar Kushwaha <prabhakar@freescale.com>
> Signed-off-by: Hemant Nautiyal <hemant.nautiyal@freescale.com>
> 
> ---
> Please note this patch depends upon following patch:
>  "driver/mtd:IFC NAND:Initialise internal SRAM before any write"
>   http://patchwork.ozlabs.org/patch/183550/
>    
> 
>  drivers/mtd/nand/fsl_ifc_nand.c |    4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)

Applied to u-boot-nand-flash -- I missed it earlier.  Next time please
make sure "nand" is in the subject line.  Ideally prefix it as
"nand/fsl_ifc: wait tWB time..." rather than "driver/mtd/IFC:Wait tWB
time...".

-Scott