Re: [PATCH v5 07/12] mtd: nand: add Samsung K9GBG08U0A-M to nand_ids table

[Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>]

On 05/20/2015 11:06 AM, Antoine Tenart wrote:
> On Sat, May 16, 2015 at 03:57:00PM -0300, Ezequiel Garcia wrote:
>> On 05/11/2015 11:58 AM, Antoine Tenart wrote:
>>> Add the full description of the Samsung K9GBG08U0A-M nand chip in the
>>> nand_ids table.
>>>
>>> Signed-off-by: Antoine Tenart <antoine.tenart@free-electrons.com>
>>> ---
>>>  drivers/mtd/nand/nand_ids.c | 4 ++++
>>>  1 file changed, 4 insertions(+)
>>>
>>> diff --git a/drivers/mtd/nand/nand_ids.c b/drivers/mtd/nand/nand_ids.c
>>> index dd620c19c619..500c33e1db06 100644
>>> --- a/drivers/mtd/nand/nand_ids.c
>>> +++ b/drivers/mtd/nand/nand_ids.c
>>> @@ -50,6 +50,10 @@ struct nand_flash_dev nand_flash_ids[] = {
>>>  		{ .id = {0xad, 0xde, 0x94, 0xda, 0x74, 0xc4} },
>>>  		  SZ_8K, SZ_8K, SZ_2M, 0, 6, 640, NAND_ECC_INFO(40, SZ_1K),
>>>  		  4 },
>>> +	{"NAND 4GiB 3,3V 8-bit",
>>> +		{ .id = {0xec, 0xd7, 0x94, 0x76, 0x64, 0x43}, },
>>> +		  8192, 4096, SZ_1M, LP_OPTIONS, 0, 0, NAND_ECC_INFO(40, SZ_1K),
>>
>> You should stick to SZ_8K and SZ_4K here.
> 
> Right.
> 
>>
>>> +		  4 },
>>>  
>>>  	LEGACY_ID_NAND("NAND 4MiB 5V 8-bit",   0x6B, 4, SZ_8K, SP_OPTIONS),
>>>  	LEGACY_ID_NAND("NAND 4MiB 3,3V 8-bit", 0xE3, 4, SZ_8K, SP_OPTIONS),
>>>
>>
>> I found a datasheet here for K9GBG08U0A that claims to support JEDEC
>> device identification (i.e. 0x90 0x40 and 0xEC 0x40 commands). Have you
>> tested it? Any reason you are adding full ID instead?
> 
> This nand looks like another one defined in this file, so a full ID make
> sure the right parameters applies here.
> 

Oh, so you say the NAND detects the device ID and uses those parameters,
instead of doing the JEDEC detection?

Then I'd say NAND is broken and should be fixed. Brian, am I crazy?
-- 
Ezequiel Garcia, VanguardiaSur
www.vanguardiasur.com.ar