Re: [RFC 0/2] Add RISC-V Server Platform Reference Board

["Wu, Fei" <fei2.wu@intel.com>]

On 3/8/2024 6:15 AM, Marcin Juszkiewicz wrote:
> W dniu 4.03.2024 o 11:25, Fei Wu pisze:
> 
>> The RISC-V Server Platform specification[1] defines a standardized
>> set of hardware and software capabilities, that portable system
>> software, such as OS and hypervisors can rely on being present in a
>> RISC-V server platform. This patchset provides a RISC-V Server
>> Platform (RVSP) reference implementation on qemu which is in
>> compliance with the spec as faithful as possible.
> 
> I am working on sbsa-ref which is AArch64 Standard Server Platform
> implementation. Will not go through details of rvsp-ref but give some
> potential hints from my work with our platform.
> 
Hi Marcin,

Thank you for sharing this.

> 
> 1. Consider versioning the platform.
> 
> We have 'platform_version'.'major/minor' exported in
> DeviceTree-formatted data. This allows for firmware to know which of
> non-discoverable hardware features exists and which not. We use it to
> disable XHCI controller on older platform version.
> 
Looks good, I will add it.

> 
> 2. If specification allows to have non-discoverable devices then add some.
> 
> This will require you to handle them in firmware in some way. Sooner or
> later some physical hardware will be in same situation so they can use
> your firmware code as reference. We have AHCI and XHCI on system bus
> (hardcoded in firmware).
> 
This RFC currently adds the devices like AHCI as PCI devices.

> 
> 3. You are going to use EDK2 with ACPI. Hide DT from code there with
> some hardware information library.
> 
> For sbsa-ref we created SbsaHardwareInfoLib in
> https://openfw.io/edk2-devel/20240306-no-dt-for-cpu-v6-0-acd8727a1b59@linaro.org/ patchset.
> 
Looks good, I will ask my colleague working on FW part to take a look.

Thanks,
Fei.