[U-Boot] x86: ACPI support suggestion

[Gabriel Huau]

Hi Simon,

On 02/06/2015 03:14 PM, Simon Glass wrote:
> Hi,
>
> On 6 February 2015 at 16:11, Gabriel Huau <contact at huau-gabriel.fr> wrote:
>> Hi Simon,
>>
>>
>> On 02/06/2015 03:04 PM, Simon Glass wrote:
>>> Hi Gabriel,
>>>
>>> On 6 February 2015 at 16:01, Gabriel Huau <contact at huau-gabriel.fr> wrote:
>>>> Hi Bin,
>>>>
>>>> Actually I was able to try with a quick&dirty code the integration of the
>>>> ACPI tables (aml files) and it doesn't seem to be possible.
>>>> The boot to Linux is working fine, all the ACPI tables are loaded
>>>> correctly,
>>>> but the system is unstable and it seems to have some issue with the
>>>> interrupts handler.
>>>>
>>>> As debugging this kind of issues could be really tricky and involve also
>>>> a
>>>> lot of modification, I think we are stuck to port the ACPI support from
>>>> coreboot to u-boot.
>>>>
>>>> I will try to work on a first draft and see how things look like.
>>> One thing to note is that U-Boot may not currently set up the PCI
>>> interrupts fully. Or perhaps the problem is that ACPI needs to match.
>>> What platform are you using?
>>>
>>> [snip]
>>
>> MinnowBoard Max (BayTrail).
>>
>> Actually, you may be right, I didn't check this part.
>>
> Actually that uses an FSP so might already be correct, but it is
> certainly worth checking.

I just checked the dmesg again and I didn't see that the first time:

[    0.723098] ACPI: PCI Interrupt Link [LNKA] (IRQs 3 4 5 6 7 10 12 14 
15) *0, disabled.
[    0.732328] ACPI: PCI Interrupt Link [LNKB] (IRQs 3 4 5 6 7 11 12 14 
15) *0, disabled.
[    0.741551] ACPI: PCI Interrupt Link [LNKC] (IRQs 3 4 5 6 7 10 12 14 
15) *0, disabled.
[    0.750782] ACPI: PCI Interrupt Link [LNKD] (IRQs 3 4 5 6 7 11 12 14 
15) *0, disabled.
[    0.760006] ACPI: PCI Interrupt Link [LNKE] (IRQs 3 4 5 6 7 10 12 14 
15) *0, disabled.

So I believe the PIRQ routing is missing in u-boot. I checked in the 
source of Coreboot, and actually everything is done in the southcluster 
initialization.
Also, I saw that the GPIO iomap wasn't done and it appeared that the 
USB2 port wasn't powered up (the white one), enabling the port allow us 
to use of both port in the EHCI mode.

I'll give a try to initialize the PIRQ and see how things is going.

> Regards,
> Simon