Re: [PATCH v2 14/17] Silicon/Ampere: Update ArmPlatformLib to work with changed ARM_CORE_INFO

["Leif Lindholm" <leif@nuviainc.com>]

On Sun, Jan 30, 2022 at 11:36:51 +0100, Ard Biesheuvel wrote:
> On Sun, 19 Dec 2021 at 04:36, Nhi Pham <nhi@os.amperecomputing.com> wrote:
> >
> > Hi Rebecca,
> >
> > Leif is merging the rest of Altra port to the edk2-platforms which has
> > SRAT ACPI table consuming the CPU Core Info table. Therefore, we will
> > need to fix the SRAT too. I would defer the fix until the Altra port is
> > fully merged.
> >
> 
> This seems to be stalled so to make progress, I am going to merge this.

Thanks, that was the right call.

Apologies for radio silence, catching up on backlog (including
remainder of Altra port) now.

/
    Leif

> > On 17/12/2021 05:07, Rebecca Cran wrote:
> > > The ARM_CORE_INFO struct has been updated so the MPIDR is now a single
> > > field instead of separate cluster/core fields. Update ArmPlatformLib.
> > >
> > > Signed-off-by: Rebecca Cran <rebecca@nuviainc.com>
> > > ---
> > >   Silicon/Ampere/AmpereAltraPkg/Library/ArmPlatformLib/ArmPlatformLib.c | 5 ++---
> > >   1 file changed, 2 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/Silicon/Ampere/AmpereAltraPkg/Library/ArmPlatformLib/ArmPlatformLib.c b/Silicon/Ampere/AmpereAltraPkg/Library/ArmPlatformLib/ArmPlatformLib.c
> > > index 5b4be0e55516..f2ec923d6f8d 100644
> > > --- a/Silicon/Ampere/AmpereAltraPkg/Library/ArmPlatformLib/ArmPlatformLib.c
> > > +++ b/Silicon/Ampere/AmpereAltraPkg/Library/ArmPlatformLib/ArmPlatformLib.c
> > > @@ -108,9 +108,8 @@ PrePeiCoreGetMpCoreInfo (
> > >       }
> > >       SocketId = SOCKET_ID (Index);
> > >       ClusterId = CLUSTER_ID (Index);
> > > -    mArmPlatformMpCoreInfoTable[mArmPlatformCoreCount].ClusterId = SocketId;
> > > -    mArmPlatformMpCoreInfoTable[mArmPlatformCoreCount].CoreId =
> > > -      (ClusterId << 8) | (Index % PLATFORM_CPU_NUM_CORES_PER_CPM);
> > > +    mArmPlatformMpCoreInfoTable[mArmPlatformCoreCount].Mpidr = GET_MPID (
> > > +      SocketId, (ClusterId << 8) | (Index % PLATFORM_CPU_NUM_CORES_PER_CPM));
> >
> > For Ampere Altra, the correct MPIDR encoding is SocketId << 32 |
> > ClusterId << 16 | (Index % PLATFORM_CPU_NUM_CORES_PER_CPM) << 8
> >
> > It would be the same what
> > Platform/Ampere/JadePkg/Drivers/AcpiPlatformDxe/AcpiMadt.c (not
> > available yet - being merged in) is describing.
> >
> 
> Feel free to follow up with a patch that changes this into the correct
> representation, but this patch does not make it less correct than it
> already is; it just stores the socket ID in the cluster ID field in a
> different way.