[U-Boot] [PATCH v1] DOS_PBR block type is also valid dos block type.

[Stephen Warren]

On 03/13/2013 10:51 AM, Stephen Warren wrote:
> On 03/12/2013 08:58 PM, Sonic Zhang wrote:
>> Hi Stephen,
>>
>> On Tue, Mar 12, 2013 at 11:09 AM, Stephen Warren <swarren at wwwdotorg.org> wrote:
>>> On 03/11/2013 08:57 PM, Sonic Zhang wrote:
>>>> Hi Stephen,
>>>>
>>>>
>>>> On Tue, Mar 12, 2013 at 1:28 AM, Stephen Warren <swarren at wwwdotorg.org> wrote:
>>>>> On 03/11/2013 03:56 AM, sonic.adi at gmail.com wrote:
>>>>>> From: Sonic Zhang <sonic.zhang at analog.com>
>>>>>>
>>>>>> - Should return 0 for both DOS_MBR and DOS_PBR block types in test_part_dos().
>>>>>
>>>>> What problem does this solve?
>>>>>
>>>>> I don't believe this change is correct. The purpose of test_part_dos()
>>>>> is to determine whether a block device contains an MS-DOS partition table.
>>>>>
>>>>> Such a partition table is present in an MBR, but not a PBR. A PBR
>>>>> contains a *FAT file-system, and does not include a partition table.
>>>>
>>>> The SD card formated by windows 7 into one FAT partition can't be
>>>> initialized correct in u-boot function init_part() after you reuses
>>>> function test_block_type() in function test_part_dos(). So, files on
>>>> that partition can't be displayed when run command "fatls mmc 0".
>>>>
>>>> The only difference in your change is to mark dos partition with flag
>>>> DOS_PBR invalid.
>>>
>>> I did test a raw FAT filesystem on an SD card without any partition
>>> table, and it worked fine. Admittedly I created the layout/filesystem
>>> with Linux rather than Windows, but I don't think the layout would be
>>> any difference. What if you "fatls mmc 0:0" rather than "fatls mmc 0";
>>> does that make any difference?
>>
>> "fatls mmc 0:0" makes no difference.
> 
> I have reproduced this. However, I believe it's not a simple "the code
> is wrong" issue, but rather some kind of issue with stale state sticking
> around.

Oh, actually perhaps I haven't. What is the exact error message that you
see?

If I apply your patch, it doesn't solve the problem that I described; I
suspect the problem you're seeing is something different.