[U-Boot] [PATCH] mtd: cfi: Fix checking status register feature

[Marek Vasut]

On 11/21/2017 03:52 AM, York Sun wrote:
> On 11/18/2017 11:09 AM, York Sun wrote:
>> Commit 72443c7f7d21 ("mtd: cfi: Add support for status register
>> polling") added a feature check to determine if status register
>> is available for certain flash chips. The "lower software bits"
>> register used to determine this feature is not backward compati-
>> ble. Older flash chips without this feature has reserved value
>> 0xff. Instead of checking "lower software bits" register, use
>> CFI primary vendor-specific extended query. Since CFI version
>> 1.4, software features can be read from offset 0x53 according to
>> document AN201168 from Cypress.
>>
>> Signed-off-by: York Sun <york.sun at nxp.com>
>> CC: Marek Vasut <marek.vasut at gmail.com>
>> ---
>>
>>  drivers/mtd/cfi_flash.c | 12 +++++++++---
>>  1 file changed, 9 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/mtd/cfi_flash.c b/drivers/mtd/cfi_flash.c
>> index 8a5babe..f096e03 100644
>> --- a/drivers/mtd/cfi_flash.c
>> +++ b/drivers/mtd/cfi_flash.c
>> @@ -1694,7 +1694,7 @@ static void cmdset_amd_read_jedec_ids(flash_info_t *info)
>>  {
>>  	ushort bankId = 0;
>>  	uchar  manuId;
>> -	uchar  lsbits;
>> +	uchar  feature;
>>  
>>  	flash_write_cmd(info, 0, 0, AMD_CMD_RESET);
>>  	flash_unlock_seq(info, 0);
>> @@ -1710,8 +1710,14 @@ static void cmdset_amd_read_jedec_ids(flash_info_t *info)
>>  	}
>>  	info->manufacturer_id = manuId;
>>  
>> -	lsbits = flash_read_uchar(info, FLASH_OFFSET_LOWER_SW_BITS);
>> -	info->sr_supported = lsbits & BIT(0);
>> +	debug("info->ext_addr = 0x%x, cfi_version = 0x%x\n",
>> +	      info->ext_addr, info->cfi_version);
>> +	if (info->ext_addr && info->cfi_version >= 0x3134) {
>> +		/* read software feature (at 0x53) */
>> +		feature = flash_read_uchar(info, info->ext_addr + 0x13);
>> +		debug("feature = 0x%x\n", feature);
>> +		info->sr_supported = feature & 0x1;
>> +	}
>>  
>>  	switch (info->chipwidth){
>>  	case FLASH_CFI_8BIT:
>>
> 
> Mark,
> 
> Can you test this patch on your platforms? I verified on my boards.

Yes, I am getting to it ... will do this week.

> York
> 


-- 
Best regards,
Marek Vasut