Re: [edk2-platforms][PATCH 1/1] Platform/RPi/AcpiTables: Update all tables to latest ACPI

["Pete Batard" <pete@akeo.ie>]

On 2020.05.06 13:50, Ard Biesheuvel wrote:
> On 5/6/20 2:45 PM, Pete Batard wrote:
>> On 2020.05.06 13:26, Ard Biesheuvel wrote:
>>> On 5/6/20 1:37 PM, Pete Batard wrote:
>>> ...
>>>> Therefore, since we do see a need for ACPI 6.x features, and
>>>> effectively have a 6.3 table with PPTT, and also since we have
>>>> tested that we are not seeing ill effects from doing so for the
>>>> most common OSes we support, we bring all of the relevant ACPI
>>>> tables to version 6.3.
>>>>
>>>> This is mostly accomplished by simply altering the version of
>>>> ACPI being references in the macros,
>>>
>>> OK, so even the macros that resolve to the exact same code are 
>>> renamed. I suppose this means a blanket rename of everything once 
>>> ACPI 6.4 comes out?
>>
>> No.
>>
>> I am considering that we are still in the process of introducing the 
>> platform, therefore we introduce it with the most up to date version 
>> of ACPI at that time.
>>
>> Though I could see some point in doing so, I have no plan to update 
>> out ACPI for the Pi's every time a new version is released, unless 
>> there is an actual need to do so for a specific table or there is a 
>> blanket request (from seeing lots of folks using our code as a 
>> starting point) that warrants it.
>>
>> In other words, even as RPi3 was introduced a year ago, I consider 
>> that we are still in the process of adding RPi3/RPi4 as a brand new 
>> platform, and therefore want to use the most up to date ACPI at the 
>> time of introduction. But I'm definitely not making a point of trying 
>> to follow ACPI updates past that this.
>>
> 
> Good.
> 
>>>> except for the new fields
>>>> being initialized in the MADT table where we:
>>>> * Use 1 for GICR Base Address in GICC_STRUCTURE_INIT because, even
>>>>    as this field is not supposed to apply to any of our platforms,
>>>>    this is what Microsoft used in the original Pi 3 hardcoded MADT
>>>>    blobs and Windows 10 doesn't boot on the Pi 3 if set to 0.
>>>
>>> Fair enough.
>>>
>>>> * Use 2 for GIC version in GIC_DISTRIBUTOR_INIT, since the Pi 4 GIC
>>>>    is v2 only.
>>>>
>>>
>>> OK. But you are introducing new references to ACPI_6_0 macros here. 
>>> If the point is to rename everything for cosmetic reasons, shouldn't 
>>> you use 6.3 there as well?
>>
>> Well, EFI_ACPI_6_0_GIC_DISTRIBUTOR_INIT was not updated for 6_1, 6_2, 
>> 6_3 (most likely because the macro, which is defined in 
>> EmbeddedPkg/Include/Library/AcpiLib.h applies the same for all 6.x 
>> versions), so I just used the highest version I could find, which is 
>> 6_0. This is based on what I saw other platforms do.
>>
>> I don't mind sending an EDK2 patch to add the various 
>> EFI_ACPI_6_x_GIC_DISTRIBUTOR_INIT if that's what you request, but that 
>> seems a bit like overkill and may break existing platforms, because it 
>> will most likely require moving EFI_ACPI_6_0_GIC_DISTRIBUTOR_INIT to a 
>> different header (MdePkg/Include/IndustryStandard/Acpi60.h).
>>
> 
> Fair enough.
> 
> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@arm.com>
> 
> Pushed as 66d1b02429fa..11189124fbc2

Thanks!

/Pete