[U-Boot] u-boot for Snow problem

[Simon Glass]

Hi Michal,

On 4 March 2015 at 05:58, Michal Suchanek <hramrach at gmail.com> wrote:
> On 4 March 2015 at 13:29, Sjoerd Simons <sjoerd.simons at collabora.co.uk> wrote:
>> On Wed, 2015-03-04 at 11:48 +0100, Michal Suchanek wrote:
>>> On 4 March 2015 at 00:46, Simon Glass <sjg at chromium.org> wrote:
>>> > Hi Michal,
>>> >
>>> > On 2 March 2015 at 04:25, Michal Suchanek <hramrach at gmail.com> wrote:
>>> >> Hello,
>>> >>
>>> >> On 18 February 2015 at 06:24, Michal Suchanek <hramrach at gmail.com> wrote:
>>> >>> On 18 February 2015 at 03:27, Simon Glass <sjg at chromium.org> wrote:
>>> >>>> Hi Michal,
>>> >>>>
>>> >>>> On 16 February 2015 at 04:41, Michal Suchanek <hramrach at gmail.com> wrote:
>>> >>>>> On 13 February 2015 at 05:51, Simon Glass <sjg at chromium.org> wrote:
>>> >>>>>> Hi Michal,
>>> >>>>>>
>>> >>>>>> On 11 February 2015 at 10:16, Michal Suchanek <hramrach at gmail.com> wrote:
>>> >>>>>>>
>>> >>>>>>> Hello,
>>> >>>>>>>
>>> >>>>>>> I changed the SYS_START to work around the bug in the manufacturer
>>> >>>>>>> firmware, applied snow_defconfig, built u-boot.bin, packed it into
>>> >>>>>>> kernel uimage, signed it, copied it to a kernel partition, bumped
>>> >>>>>>> priority of the partition, and rebooted.
>>> >>>>>>>
>>> >>>>>>
>>> >>>>>> Do you mean u-boot-dtb.bin? If not you won't get a device tree and it
>>> >>>>>> won't work.
>>> >>>>>
>>> >>>>> No, u-boot.bin. With u-boot-dtb.bin I get a snow # prompt on the
>>> >>>>> built-in LCD, and working keyboard.
>>> >>>>
>>> >>>> OK sounds like it is working, good! I wonder if we should have a page
>>> >>>> on elinux.org?
>>> >>
>>> >> It is working to some extent.
>>> >>
>>> >> I managed to load kernel from the emmc which works fine but the kernel
>>> >> cannot read the emmc after it boots because it does not properly parse
>>> >> the partitioning scheme. This should be trivially fixable in the
>>> >> kernel and might actually work if I updated my sources but rebasing
>>> >> the extra patches required for Snow is not automatically handled.
>>> >>
>>> >> On the other hand, the linux kernel has no problem with the SDXC card
>>> >> in the SD slot and can read it just fine. Unfortunately, u-boot
>>> >> complains about EFI partition errors and won't load anything from the
>>> >> card. I tried two different GPT partitioning tools on the card and
>>> >> both say that the partition layout is fine and that I have the default
>>> >> 128 entries.
>>> >>
>>> >> How can I tell why u-boot does not like my GPT label?
>>> >
>>> > You could debug it in U-Boot and see what is going wrong.
>>>
>>> Presumably. How do I do that?
>>
>> You should be able to use the u-boot sandbox build (on your intel box)
>> and load image from your device in there using the sb command. The
>> partitioning code isn't device specific, so that should give you a
>> convenient way to reproduce the issue and debug it without needing a
>> serial.
>>
>
> The problem is not that I do not have a serial port. It makes grepping
> for error messages inconvenient but that's it.
>
> The problem is that u-boot does not provide any diagnostics as to why
> it does not like the partition layout.

Yes it would be good to improve the error messages.

Regards,
Simon