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

[Stephen Warren]

On 03/11/2013 08:59 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 reuse the
> function test_block_type() in function test_part_dos(). So, files on
> that partition can't be displayed when running command "fatls mmc 0".
> 
> The only difference in your change is to mark dos partition with flag
> DOS_PBR invalid.

Hmmm. I obtained an SD card that had been formatted in Windows 7
(inserted SD card, right-clicked on it in Explorer, selected Format,
selected default FAT32 options), and could not reproduce this issue.

Can you give more explicit instructions on how to reproduce this
problem? Perhaps a hexdump of the first sector would also help, or
uploading a heavily compressed image of the SD card that I can dd onto mine.

Also, what branch/commit of U-Boot are you using?