[U-Boot] Next for x86?

[Bin Meng]

Hi Simon,

On Thu, Nov 26, 2015 at 12:52 AM, Simon Glass <sjg at chromium.org> wrote:
> Hi Bin,
>
> On 19 November 2015 at 20:38, Bin Meng <bmeng.cn at gmail.com> wrote:
>> Hi Simon,
>>
>> On Fri, Nov 20, 2015 at 11:09 AM, Simon Glass <sjg at chromium.org> wrote:
>>> Hi,
>>>
>>> I'm wondering what might come next for U-Boot x86 support.
>>>
>>> The PCI conversion to driver model is coming along nicely. The ACPI
>>> support is only partially there but it is a good start.
>
> I have another series of PCI patches in the works and hope to get
> these out in a few weeks. The intent is to fully move x86 to use the
> driver model API.
>
>>>
>>> What else? More platforms? Other features? Better support for existing
>>> platforms?
>>>
>>
>> Two biggest feature gaps so far are complete ACPI support, and SMM
>> support. ACPI is pretty much a must-have if we want power management
>> feature in the OS. For SMM, I am not convinced that we have to do that
>> in U-Boot, for example those BIOS guys invented USB legacy support
>> (I/O port emulation of PS/2 keyboard) via SMM but today we have native
>> USB support and we should not do such with SMM in U-Boot. One corner
>> case is that some ACPI AML codes on some commercial BIOS trap the ACPI
>> calls into SMM where SMM is a must-have. Unfortunately such
>> limitations exist as there are still lots of unpublished chipset docs
>> from various vendors who want to protect their IP (so-called).
>>
>> ACPI support seems to be a must if we want to support booting Windows,
>> also we may need help from SeaBIOS (chain-loaded from U-Boot).
>
> Yes we should try to get that finished. It seems pretty close at least
> on qemu and minnowboard max.
>
>>
>> For other features, what I can think of now are:
>> - New platform support which relies on FSP. With FSP it is quite easy
>> to add a new platform support for Intel processors.
>> - FSP spec 1.1 support, however Intel has not released any FSP package
>> based on FSP spec 1.1. I believe their next gen Atom/Core processors'
>> FSP will support FSP 1.1 (like Braswell, Skylake)
>
> Yes it seems like this will happen when we get the first board that supports it.
>
>> - TPM support, and Intel TXT/TXE
>
> There is LPC TPM support at present so perhaps that is a start.
>
>> - xHCI support on Intel chipset (looks the U-Boot xHCI driver is not
>> working for Intel)
>
> Agreed, this shouldn't be too tricky as it is a standard.
>
>> - Audio support (maybe just providing audio codec's verb table in U-Boot)
>
> There is basic speaker support, and on a few ARM boards there is basic
> audio support (playing a waveform, and code to generate a waveform).
> This is pretty platform-specific as each codec is different. Do you
> have a board with a built-in audio codec?
>

Looks Crown Bay and Bayley Bay boards have on-board audio codec. By
supporting audio I mean to enable OS to have the audio functionality.
I am not aware of U-Boot is able to play sound :)

Regards,
Bin