[U-Boot] U-boot qemu-x86 :load acpi tables from fw_cfg.

[Saket Sinha]

Hi Simon,

>>
>> Is it possible for us to add support to qemu to provide acpi tables
>> via fw_cfg in u-boot ?
>>
>> If we find acpi tables in fw_cfg try loading them, otherwise fallback
>> to the builtin acpi tables.
>>
>> Coreboot does it in the following way -
>> http://review.coreboot.org/#/c/4040/
>
> It seems like it might be useful to implement this in U-Boot. Perhaps
> look at this after you have the built-in support running?
>

I guess it would be extremely useful for u-boot.

It is being used by q-boot, a new minimal x86 firmware for QEMU.
http://lwn.net/Articles/645455/
https://github.com/bonzini/qboot

q-boot is able to give a minimal booting time, with the help of
fw_cfg, by reading both the kernel and initrd image
from fw_cfg.
I guess ACPI support for both q-boot and qemu-x86 in u-boot can be
implemented on similar lines.


Regards,
Saket Sinha