On 08/25/2017 03:46 AM, Paul Barker wrote:
On Fri, Aug 25, 2017 at 2:46 AM, Simon Glass <s...@chromium.org> wrote:
Hi,

On 20 August 2017 at 20:59, Simon Glass <s...@chromium.org> wrote:
Hi Paul,

On 3 August 2017 at 11:42, Tom Rini <tr...@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.

As background information, note that there are two ways U-Boot can work:

1) Load a DTB from "disk", and pass that to the kernel. This is typically used for upstream kernels, since at least historically the DTBs supplied by the RPi Foundation and loaded/modified by the VideoCore firmware use a non-upstream schema, so need to be replaced with an upstream-compatible DTB by U-Boot.

2) Pass through the DTB from the VideoCore firmware to the kernel. This is almost certainly required when booting a downstream RPi Foundation kernel.

Historically, U-Boot has only implemented option 1. I think recent versions of U-Boot support option 2, although you'd have to make some configuration(environment) changes to use that method. That's because historically, U-Boot has been targeted at booting upstream kernels.

I haven't investigated whether any of this is related to the problem you're seeing.
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