On 08/25/2017 03:46 AM, Paul Barker wrote:
On Fri, Aug 25, 2017 at 2:46 AM, Simon Glass sjg@chromium.org wrote:
Hi,
On 20 August 2017 at 20:59, Simon Glass sjg@chromium.org wrote:
Hi Paul,
On 3 August 2017 at 11:42, Tom Rini trini@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.