[U-Boot] [PATCH v2 00/22] x86: Add ACPI S3 resume support

[Stefan Roese]

Hi Bin,

On 21.04.2017 16:24, Bin Meng wrote:
> This adds ACPI S3 (suspend to ram) resume capability in U-Boot.
> With S3 support within U-Boot, the board wakes up and resumes to
> OS very quickly.
>
> This so far is enabled and tested on Intel MinnowMax board. Please
> check README.x86 for how to test it with a plain Linux kernel.
> Linux (w/ or w/o SeaBIOS) and Windows 10 (w/ SeaBIOS) were tested.
>
> This series is available for testing at u-boot-x86/s3-working.

Thank you very much for working on this. I've started testing this
patchset on my congatec BayTrail SoM based board. Booting into
a v4.11-rc based kernel with serial console works just fine.
Suspend and resume work nicely and fast! :)

Booting Ubuntu 16.04 (kernel 4.4) with graphical interface seems to
have some (rare) problems though. When I boot into Ubuntu with the
correct "console=" configuration (log via serial console), suspend
/ resume seems to work fine as well - at least in the tests I did
so far. But when I don't provide this "console=" and use "quiet"
instead, resume does not seem to work reliably. Most of the times it
works just fine as well, but sometimes the graphical user interface
doesn't come up at all after resuming (display stays in power safe
mode). The U-Boot log is the same in both cases:

Jumping to OS waking vector 0009a1d0

And the POST debug byte is also identical (0x40).

Do you have any ideas, where this might come from? Could you
perhaps check this on MinnoxMax as well, if such a setup also
sometimes has problems with resuming? Is there anything that I could
do to test this on my platform?

Thanks,
Stefan