[U-Boot] [PATCH][v2] driver/nand: Update SRAM initialize logic for IFC.

[U-Boot] [PATCH][v2] driver/nand: Update SRAM initialize logic for IFC.

[Prabhakar Kushwaha]

IFC controller v1.1.0 requires internal SRAM initialize by reading
NAND flash. Higher controller versions have provided "SRAM init" bit in
NCFGR register space.

update SRAM initialize logic to reflect the same.

Also print error message in case of Page read error.

Signed-off-by: Prabhakar Kushwaha <prabhakar@freescale.com>
---
Changes for v2:
	- Updated error handling

 drivers/mtd/nand/fsl_ifc_nand.c |   35 +++++++++++++++++++++++++++++++----
 include/fsl_ifc.h               |    2 ++
 2 files changed, 33 insertions(+), 4 deletions(-)

diff --git a/drivers/mtd/nand/fsl_ifc_nand.c b/drivers/mtd/nand/fsl_ifc_nand.c
index 27f5177..280e14e 100644
--- a/drivers/mtd/nand/fsl_ifc_nand.c
+++ b/drivers/mtd/nand/fsl_ifc_nand.c
@@ -806,12 +806,30 @@ static void fsl_ifc_select_chip(struct mtd_info *mtd, int chip)
 {
 }
 
-static void fsl_ifc_sram_init(void)
+static int fsl_ifc_sram_init(uint32_t ver)
 {
 	struct fsl_ifc *ifc = ifc_ctrl->regs;
 	uint32_t cs = 0, csor = 0, csor_8k = 0, csor_ext = 0;
+	uint32_t ncfgr = 0;
 	long long end_tick;
 
+	if (ver > FSL_IFC_V1_1_0) {
+		ncfgr = ifc_in32(&ifc->ifc_nand.ncfgr);
+		ifc_out32(&ifc->ifc_nand.ncfgr, ncfgr | IFC_NAND_SRAM_INIT_EN);
+
+		/* wait for  SRAM_INIT bit to be clear or timeout */
+		end_tick = usec2ticks(IFC_TIMEOUT_MSECS * 1000) + get_ticks();
+		while (end_tick > get_ticks()) {
+			ifc_ctrl->status =
+				ifc_in32(&ifc->ifc_nand.nand_evter_stat);
+
+			if (!(ifc_ctrl->status & IFC_NAND_SRAM_INIT_EN))
+				return 0;
+		}
+		printf("fsl-ifc: Failed to Initialise SRAM\n");
+		return 1;
+	}
+
 	cs = ifc_ctrl->cs_nand >> IFC_NAND_CSEL_SHIFT;
 
 	/* Save CSOR and CSOR_ext */
@@ -854,11 +872,18 @@ static void fsl_ifc_sram_init(void)
 			break;
 	}
 
+	if (ifc_ctrl->status != IFC_NAND_EVTER_STAT_OPC) {
+		printf("fsl-ifc: Failed to Initialise SRAM\n");
+		return 1;
+	}
+
 	ifc_out32(&ifc->ifc_nand.nand_evter_stat, ifc_ctrl->status);
 
 	/* Restore CSOR and CSOR_ext */
 	ifc_out32(&ifc_ctrl->regs->csor_cs[cs].csor, csor);
 	ifc_out32(&ifc_ctrl->regs->csor_cs[cs].csor_ext, csor_ext);
+
+	return 0;
 }
 
 static int fsl_ifc_chip_init(int devnum, u8 *addr)
@@ -868,7 +893,7 @@ static int fsl_ifc_chip_init(int devnum, u8 *addr)
 	struct fsl_ifc_mtd *priv;
 	struct nand_ecclayout *layout;
 	uint32_t cspr = 0, csor = 0, ver = 0;
-	int ret;
+	int ret = 0;
 
 	if (!ifc_ctrl) {
 		fsl_ifc_ctrl_init();
@@ -1010,8 +1035,10 @@ static int fsl_ifc_chip_init(int devnum, u8 *addr)
 	}
 
 	ver = ifc_in32(&ifc_ctrl->regs->ifc_rev);
-	if (ver == FSL_IFC_V1_1_0)
-		fsl_ifc_sram_init();
+	if (ver >= FSL_IFC_V1_1_0)
+		ret = fsl_ifc_sram_init(ver);
+	if (ret)
+		return ret;
 
 	ret = nand_scan_ident(mtd, 1, NULL);
 	if (ret)
diff --git a/include/fsl_ifc.h b/include/fsl_ifc.h
index 630e4b4..b353b04 100644
--- a/include/fsl_ifc.h
+++ b/include/fsl_ifc.h
@@ -367,6 +367,8 @@
  */
 /* Auto Boot Mode */
 #define IFC_NAND_NCFGR_BOOT		0x80000000
+/* SRAM INIT EN */
+#define IFC_NAND_SRAM_INIT_EN		0x20000000
 /* Addressing Mode-ROW0+n/COL0 */
 #define IFC_NAND_NCFGR_ADDR_MODE_RC0	0x00000000
 /* Addressing Mode-ROW0+n/COL0+n */
-- 
1.7.9.5

[U-Boot] [PATCH][v2] driver/nand: Update SRAM initialize logic for IFC.

[Scott Wood]

On Thu, 2014-06-12 at 12:14 +0530, Prabhakar Kushwaha wrote:
> IFC controller v1.1.0 requires internal SRAM initialize by reading
> NAND flash. Higher controller versions have provided "SRAM init" bit in
> NCFGR register space.
> 
> update SRAM initialize logic to reflect the same.
> 
> Also print error message in case of Page read error.
> 
> Signed-off-by: Prabhakar Kushwaha <prabhakar@freescale.com>
> ---
> Changes for v2:
> 	- Updated error handling
> 
>  drivers/mtd/nand/fsl_ifc_nand.c |   35 +++++++++++++++++++++++++++++++----
>  include/fsl_ifc.h               |    2 ++
>  2 files changed, 33 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/mtd/nand/fsl_ifc_nand.c b/drivers/mtd/nand/fsl_ifc_nand.c
> index 27f5177..280e14e 100644
> --- a/drivers/mtd/nand/fsl_ifc_nand.c
> +++ b/drivers/mtd/nand/fsl_ifc_nand.c
> @@ -806,12 +806,30 @@ static void fsl_ifc_select_chip(struct mtd_info *mtd, int chip)
>  {
>  }
>  
> -static void fsl_ifc_sram_init(void)
> +static int fsl_ifc_sram_init(uint32_t ver)
>  {
>  	struct fsl_ifc *ifc = ifc_ctrl->regs;
>  	uint32_t cs = 0, csor = 0, csor_8k = 0, csor_ext = 0;
> +	uint32_t ncfgr = 0;
>  	long long end_tick;
>  
> +	if (ver > FSL_IFC_V1_1_0) {

It would be better to check that ver >= the first version that supports
this, rather than > the last version that doesn't.

How much benefit is there in doing this versus continuing with the
current code?

Should we determine the IFC version at compile time instead, so that we
don't need to carry around both versions of the code in the binary?

-Scott

[U-Boot] [PATCH][v2] driver/nand: Update SRAM initialize logic for IFC.

[Prabhakar Kushwaha]

Hi Scott,


On 6/14/2014 2:10 AM, Scott Wood wrote:
> On Thu, 2014-06-12 at 12:14 +0530, Prabhakar Kushwaha wrote:
>> IFC controller v1.1.0 requires internal SRAM initialize by reading
>> NAND flash. Higher controller versions have provided "SRAM init" bit in
>> NCFGR register space.
>>
>> update SRAM initialize logic to reflect the same.
>>
>> Also print error message in case of Page read error.
>>
>> Signed-off-by: Prabhakar Kushwaha <prabhakar@freescale.com>
>> ---
>> Changes for v2:
>> 	- Updated error handling
>>
>>   drivers/mtd/nand/fsl_ifc_nand.c |   35 +++++++++++++++++++++++++++++++----
>>   include/fsl_ifc.h               |    2 ++
>>   2 files changed, 33 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/mtd/nand/fsl_ifc_nand.c b/drivers/mtd/nand/fsl_ifc_nand.c
>> index 27f5177..280e14e 100644
>> --- a/drivers/mtd/nand/fsl_ifc_nand.c
>> +++ b/drivers/mtd/nand/fsl_ifc_nand.c
>> @@ -806,12 +806,30 @@ static void fsl_ifc_select_chip(struct mtd_info *mtd, int chip)
>>   {
>>   }
>>   
>> -static void fsl_ifc_sram_init(void)
>> +static int fsl_ifc_sram_init(uint32_t ver)
>>   {
>>   	struct fsl_ifc *ifc = ifc_ctrl->regs;
>>   	uint32_t cs = 0, csor = 0, csor_8k = 0, csor_ext = 0;
>> +	uint32_t ncfgr = 0;
>>   	long long end_tick;
>>   
>> +	if (ver > FSL_IFC_V1_1_0) {
> It would be better to check that ver >= the first version that supports
> this, rather than > the last version that doesn't.

here only 2 type of code is present i.e.  (ver == FSL_IFC_V1_1_0) and 
(ver > FSL_IFC_V1_1_0).
if i put  (ver == FSL_IFC_V1_1_0) earlier a lots of code go in "if ". I 
am trying to avoid it to make code more cleaner.

> How much benefit is there in doing this versus continuing with the
> current code?

Existing code is perfect for 8KB internal SRAM as we are reading 8KB Page.
As IFC 2.0 has 16KB SRAM, either I have to read 16KB page or I have to 
read 2 8KB page to fill complete SRAM.

in future, there may be possibility of > 16KB internal SRAM. So I 
decided to use SRAM init bit.

> Should we determine the IFC version at compile time instead, so that we
> don't need to carry around both versions of the code in the binary?
>

Compile time option can be used. But in Linux driver it may not be 
possible.
I am trying to have same code base in u-boot and Linux for maintainability.

--prabhakar