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

[Paul Barker]

On Fri, Aug 25, 2017 at 2:46 AM, Simon Glass <sjg at chromium.org> wrote:
> Hi,
>
> On 20 August 2017 at 20:59, Simon Glass <sjg at chromium.org> wrote:
>> Hi Paul,
>>
>> On 3 August 2017 at 11:42, Tom Rini <trini at konsulko.com> wrote:
>>> On Thu, Aug 03, 2017 at 09:42:13AM -0600, Stephen Warren wrote:
>>>> On 08/03/2017 07:45 AM, Simon Glass wrote:
>>>> ...
>>>> >I'm not sure if we have a Raspberry Pi in a test farm anywhere. I
>>>> >should be able to look next week if no one can figure these out
>>>> >beforehand.
>>>>
>>>> I thought that Tom had some Pis in his test farm?
>>>
>>> I have an RPi 3, but we don't have Linux boot tests atm.  I'm talking
>>> with Kevin Hilman about how I might setup kernelci to test a few things
>>> in my lab, which might catch this kind of problem sooner rather than
>>> later.
>>
>> Just a note that I can repeat the CONFIG_OF_EMBED problem. I am not
>> sure what is going on or why this would prevent the kernel booting.
>> But I believe rpi has a device tree pass-through from the pre-U-Boot
>> boot loader, and I am booting with that, so perhaps it relies on
>> CONFIG_OF_EMBED in some way?
>
> I can see some code in board_fdt_blob_setup() but it does not seem to
> be enabled. For me I am able to boot Linux without CONFIG_OF_EMBED.
>
>>
>> I can also repeat the USB keyboard problem. It doesn't detect the
>> keyboard at all. For me this can be fixed by enabling
>> CONFIG_DM_KEYBOARD, so we should probably do that for all rpi boards.
>
> I have sent a patch for this.

This patch looks good. I've now got working keyboard and network in
u-boot along with a successful boot of Linux for the 2 devices I've
tested (Original rpi and rpi3 32-bit) from the following:

* U-boot 2017.07 release
* Revert "dm: arm: rpi: Drop CONFIG_OF_EMBED" (25877d4e)
* Apply backported version of your patch

The rpi firmware does provide a device tree blob at boot and my only
guess is that this is currently being overwritten or ignored. That's
masked when CONFIG_OF_EMBED is enabled as we use an embedded device
tree instead of the one provided by the rpi firmware.

For u-boot v2017.09 release is it possible to re-enable
CONFIG_OF_EMBED until we can find and fix the underlying issue? Or is
there some reason to avoid CONFIG_OF_EMBED?

>
>>
>> Re the Ethernet thing, what changes when you disable that?

CONFIG_DM_ETH was disabled purely as it depends on CONFIG_DM_USB on
the Raspberry Pi and I'd disabled that to work around the USB keyboard
issue. With CONFIG_DM_ETH, CONFIG_DM_USB and CONFIG_DM_KEYBOARD
enabled everything looks good.

Thanks,

-- 
Paul Barker
Togán Labs Ltd