[U-Boot] [NEXT PATCH v1 2/7] NAND: added NAND type to nand_ids

Stefano Babic
2012-09-07T15:23:57Z

On 07/09/2012 11:12, Stefano Babic wrote:
> On 07/09/2012 01:19, Scott Wood wrote:
>> On 09/06/2012 03:04 AM, Stefano Babic wrote:
>>> Signed-off-by: Stefano Babic <sbabic@denx.de>
>>> ---
>
> Hi Scott,
>
>>> drivers/mtd/nand/nand_ids.c | 2 ++
>>> 1 file changed, 2 insertions(+)
>>>
>>> diff --git a/drivers/mtd/nand/nand_ids.c b/drivers/mtd/nand/nand_ids.c
>>> index 3953549..fe75686 100644
>>> --- a/drivers/mtd/nand/nand_ids.c
>>> +++ b/drivers/mtd/nand/nand_ids.c
>>> @@ -131,6 +131,8 @@ const struct nand_flash_dev nand_flash_ids[] = {
>>> /* 128 Gigabit */
>>> {"NAND 16GiB 1,8V 8-bit", 0x1A, 0, 16384, 0, LP_OPTIONS},
>>> {"NAND 16GiB 3,3V 8-bit", 0x3A, 0, 16384, 0, LP_OPTIONS},
>>> + {"NAND 16GiB 3,3V 8-bit", 0x48, 4096, 16384, 0x100000,
>>> + LP_OPTIONS},
>>> {"NAND 16GiB 1,8V 16-bit", 0x2A, 0, 16384, 0, LP_OPTIONS16},
>>> {"NAND 16GiB 3,3V 16-bit", 0x4A, 0, 16384, 0, LP_OPTIONS16},
>>>
>>>
>>
>> Why does this NAND chip need things specified that are zeroes for other
>> chips?
>
> At least on this board with MX35, the chip cannot be recognized.
> Manufacturer ID and device ID are read flawlessly, but then u-boot fails
> to get the correct geometry. Setting explicitely the values, I can then
> read / write into the NAND without any problem. It can be more a problem
> related to the specific MXC NAND driver (mxc_nand.c).

It seems to me that the values returned by this flash cannot be
interpreted in nand_get_flash_type().

The values returned from a READ-ID command with address 0x00 are:

0x2C 0x48 0x04 0x4A 0xA5,

I can really get these values from the flash, so the MXC controller gets
the correct data.

However, the code in nand_base.c (lines from 2718, so not-Samsung case)
parses the answer setting the NAND as a 16-bit device, but this is
really a 8bit device. I do not know the meaning of the answer, it is not
described in the datasheet.

Cheers,
Stefano

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