On Wed, 26 Jul 2023 at 20:45, Kun Qin <kuqi...@gmail.com> wrote: > > Hi Ard, > > Our current use case is around AP core suspension and wake-ups. > > The program can suspend the secondary cores through PSCI interfaces > (after powering > them on). BSP can then wake up the suspended cores through SGI on demand. >
The use of PSCI is already dubious in the context of UEFI - combining it with the use of SGIs for communication between cores seems like a slippery slope I don't think we should be going down. > The pending interrupt manipulation is to support BSP suspension and > wakeup. We > currently use watchdog timer to wake up suspended BSPs after a timeout. > suspended APs right? > Platforms can perform needed tasks during suspension, such as core power > consumption > analysis, in UEFI environment. > > Please let me if you have any suggestions. > Is there any basis in the UEFI or PI specifications for this functionality? > On 7/26/2023 1:45 AM, Ard Biesheuvel wrote: > > On Mon, 24 Jul 2023 at 22:15, Kun Qin <kuqi...@gmail.com> wrote: > >> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4466 > >> > >> This patch series introduce a few improvements related to interrupt > >> handling for ArmGic driver and library. > >> > >> 1. The current implementation of the `ArmGicSendSgiTo` is based on GIC v2 > >> and does not work on GIC v3 and on. > >> 2. The pending interrupt related primitives does not exist for end users. > >> > >> The change added the SGI support compatible with GIC v3 and v4. A few > >> pending interrupt related utility functions were also added. > >> > >> This change was tested on QEMU, FVP and proprietary hardware platforms. > >> > >> Pathc v1 branch: https://github.com/kuqin12/edk2/tree/improve_gic_v1 > >> > >> Cc: Leif Lindholm <quic_llind...@quicinc.com> > >> Cc: Ard Biesheuvel <ardb+tianoc...@kernel.org> > >> Cc: Sami Mujawar <sami.muja...@arm.com> > >> > >> Kun Qin (3): > >> ArmPkg: ArmGic: Added support to send SGI to NS G1 EL1 > >> ArmPkg: ArmGicLib: Added GIC v3 and v4 support to ArmGicSendSgiTo > >> ArmPkg: ArmGic: Added functionalities to manipulate pending interrupts > >> > > Hello Kun, > > > > Could you please explain how this will be used by platforms? > > > > SGIs are only used by the MPcore SEC code, which is deprecated and > > shouldn't be used. And manipulating pending interrupts is another > > thing we should only support if there is a compelling use case. -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#107552): https://edk2.groups.io/g/devel/message/107552 Mute This Topic: https://groups.io/mt/100337221/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
