Re: [edk2-devel] [PATCH edk2-platforms 1/1] Platform/QemuSbsa: define NS EL2 virtual timer in GTDT

["Marcin Juszkiewicz" <marcin.juszkiewicz@linaro.org>]

W dniu 20.09.2023 o 12:04, Leif Lindholm pisze:
> On Wed, Sep 20, 2023 at 10:25:09 +0200, Marcin Juszkiewicz wrote:
>> Armv8.1+ cpus have Virtual Host Extension (VHE) which added non-secure
>> EL2 virtual timer.

> It's still valid to use other CPUs than "max" with this platform.
> Don't we need to conditionalise this based on the contents of the VH
> bits in ID_AA64MFR1_EL1?

Most of cpu cores available for SBSA Reference Platform are v8.2+ ones. 
And default is Neoverse-N1.

> Ideally, we'd add a helper function in edk2
> ArmPkg/Library/ArmLib/AArch64/AArch64Lib.c, like ArmHasCcidx(), and
> conditionalise on that.
> 
> Hmm, but we'd probably also need to move from .aslc to manually
> construction GTDT in SbsaQemuAcpiDxe...
> 
> If you're up for doing the GTDT rework, I could create the ArmLib
> helper function.

Sooner or later it needs to be done anyway as we need to add system 
timers there (which iirc only Ampere does in EDK2).



-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#108908): https://edk2.groups.io/g/devel/message/108908
Mute This Topic: https://groups.io/mt/101474460/7686176
Group Owner: devel+owner@edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub [rebecca@openfw.io]
-=-=-=-=-=-=-=-=-=-=-=-