On Wed, 11 Jan 2023 at 18:38, PierreGondois <pierre.gond...@arm.com> wrote: > > > > On 1/11/23 17:49, Ard Biesheuvel wrote: > > On Fri, 18 Nov 2022 at 17:48, PierreGondois <pierre.gond...@arm.com> wrote: > >> > >> Hello Ard, > >> > >> On 11/10/22 14:47, Ard Biesheuvel wrote: > >>> Currently, we only expose the EFI_RNG_PROTOCOL in ArmVirtQemu if QEMU > >>> provides a virtio-rng device, and it doesn't do so by default. > >>> > >>> Given that KVM exposes the ARM architected TRNG service (and has done so > >>> for a while now), let's incorporate the RngDxe driver which has recently > >>> grown support for the ARM firmware/hypervisor service. > >>> > >>> If both the service and the virtio device are available, two > >>> implementations of the RNG protocol will be exposed, but this is fine: > >>> callers that don't care about the distinction will grab the first one > >>> available. > >>> > >>> Signed-off-by: Ard Biesheuvel <a...@kernel.org> > >>> --- > >>> ArmVirtPkg/ArmVirtQemu.dsc | 11 +++++++++++ > >>> ArmVirtPkg/ArmVirtQemuFvMain.fdf.inc | 5 +++++ > >>> ArmVirtPkg/ArmVirtQemuKernel.dsc | 11 +++++++++++ > >>> 3 files changed, 27 insertions(+) > >>> > >>> diff --git a/ArmVirtPkg/ArmVirtQemu.dsc b/ArmVirtPkg/ArmVirtQemu.dsc > >>> index f77443229e8e..1771ad562225 100644 > >>> --- a/ArmVirtPkg/ArmVirtQemu.dsc > >>> +++ b/ArmVirtPkg/ArmVirtQemu.dsc > >>> @@ -140,6 +140,8 @@ [PcdsFeatureFlag.common] > >>> > >>> gArmVirtTokenSpaceGuid.PcdTpm2SupportEnabled|$(TPM2_ENABLE) > >>> > >>> + gArmTokenSpaceGuid.PcdMonitorConduitHvc|TRUE > >>> + > >> > >> It seems that the PSCI conduit needs to be dynamically set. > > > > Why? And how is this different from PSCI for resetting the system? > > The PSCI implementation used for ArmVirtQemu is parsing the conduit > to use, so it can handle both cases: > https://github.com/tianocore/edk2/blob/fe405f08a09e9f2306c72aa23d8edfbcfaa23bff/ArmVirtPkg/Library/ArmVirtPsciResetSystemLib/ArmVirtPsciResetSystemLib.c#L49 >
Hmm, that is a fair point. I wonder if we should simply detect whether we are executing at EL1 or EL2, and use HVC or SVC respectively. > > > > Note that ArmVIrtQemu was never intended to run at EL2, even if it > > seems to work to some extent. > > Ok understood. > > > > > > >> The psci conduit that should be used is configured by qemu depending on the > >> virtualization=[on|off] parameter. When off, HVC must be used (SMC > >> otherwise). > >> Cf: > >> https://github.com/qemu/qemu/blob/master/hw/arm/virt.c#L2052 > > (replacing with a permanent link) > https://github.com/qemu/qemu/blob/aa96ab7c9df59c615ca82b49c9062819e0a1c287/hw/arm/virt.c#L2080 > > >> > >> If using the wrong conduit, qemu traps the instruction and stops. > >> For KvmTool, the conduit is always HVC. > >> > >> Command used: > >> [PATH_TO]/qemu/build/qemu-system-aarch64 \ > >> -serial stdio -M virt,highmem=on,virtualization=off \ > >> -cpu cortex-a57 -smp 4 -m 4096 \ > >> -drive file=pflash0.img,format=raw,if=pflash,readonly=on \ > >> -drive file=pflash1.img,format=raw,if=pflash > >> > >> Regards, > >> Pierre > >> > >> > >> > >> > >> > > > > > -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#98307): https://edk2.groups.io/g/devel/message/98307 Mute This Topic: https://groups.io/mt/94935841/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
