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

Stefano Babic
2012-09-10T12:09:21Z

On 07/09/2012 20:56, Scott Wood wrote:

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.
>
> Does the datasheet say anything about what the ID data is supposed to
> look like and how to interpret it? I tried to download it and Micron
> shoved an NDA in my face.

I find no description in the datasheet.

>
> What kind of chip is this? Is the datasheet publicly available?
>
> These threads seem relevant:
> http://patchwork.ozlabs.org/patch/60042/
> http://old.nabble.com/-U-Boot--Add-new-NAND-flash-td29858370.html

It is the same case, as I can see, with the same chip.

>
> Does the chip support ONFI?

The chip supports ONFI, but it seems the i.MX driver does not. Quite as
described in http://patchwork.ozlabs.org/patch/60042/. READ-ID is always
sent with address 0, I do not know if we can convince the driver to send
the address.

Regards,
Stefano

--
=====================================================================
DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-53 Fax: +49-8142-66989-80 Email: sbabic at denx.de
=====================================================================