[U-Boot] U-boot 2017.07 not working on Raspberry Pi

[Paul Barker <pbarker@toganlabs.com>]

On Thu, Aug 3, 2017 at 2:45 PM, Simon Glass <sjg@chromium.org> wrote:
> Hi,
>
> On 3 August 2017 at 03:37, Mark Kettenis <mark.kettenis@xs4all.nl> wrote:
>>> Date: Thu, 3 Aug 2017 19:02:06 +1000
>>> From: Jonathan Gray <jsg@jsg.id.au>
>>>
>>>
>>> We had to revert 25877d4e4c45451c5398aec3de50e0d5befe0e9f to add
>>> CONFIG_OF_EMBED back to get OpenBSD to continue working on the rpi3.
>>
>> That revert is in particular necessary for passthrough of the device
>> tree from the Raspberry Pi firmwre to work.  I haven't investigated
>> this further yet, but it seems some of the relocation code is
>> conditionalized on CONFIG_OF_EMBED, and I suspect that when
>> CONFIG_OF_EMBED is absent, u-boot overwrites the device tree when it
>> relocates itself.
>
> I'm not sure why it needs CONFIG_OF_EMBED. Certainly U-Boot does
> relocate the DT when this is not set. But it should not be set for
> production images, only for debugging.
>

I've tried reverting just "dm: arm: rpi: Drop CONFIG_OF_EMBED"
(25877d4e) but I'm still left without a working keyboard in u-boot -
hitting keys during the countdown does not interrupt the boot process.
However the kernel can be booted with just that one commit reverted.

I've also looking into the CONFIG_OF_BOARD option. This is currently
disabled for raspberrypi devices which means that
board_fdt_blob_setup() in board/raspberrypi/rpi/rpi.c is not called.
Enabling CONFIG_OF_BOARD leads to a crash at boot with no output from
u-boot, the monitor connected to the raspberrypi just shows the colour
palette.

I can look into this further but it probably needs to wait until I can
order some RS232 adaptors and get a serial port setup for early debug
output.

Thanks,

-- 
Paul Barker
Co-Founder & Principal Engineer
Togán Labs Ltd