Re: [PATCH v10 0/8] ACPI: Unify CPU UID interface and fix ARM64 TPH steer-tag issue

["Rafael J. Wysocki" <rafael@xxxxxxxxxx>]

On Fri, Mar 20, 2026 at 4:17 AM Chengwen Feng <fengchengwen@xxxxxxxxxx> wrote:
>
> This patchset unifies ACPI Processor UID retrieval across
> arm64/loongarch/riscv/x86 via acpi_get_cpu_uid() (with input validation)
> and fixes ARM64 CPU steer-tag retrieval failure in PCI/TPH:
>
> 1-4: Add acpi_get_cpu_uid() for arm64/loongarch/riscv/x86 (update
>      respective users)
> 5: Centralize acpi_get_cpu_uid() declaration in include/linux/acpi.h
> 6: Clean up perf/arm_cspmu
> 7: Clean up ACPI/PPTT and remove unused get_acpi_id_for_cpu()
> 8: Pass ACPI Processor UID to Cache Locality _DSM
>
> The interface refactor ensures consistent CPU UID retrieval across
> architectures (no functional changes for valid inputs) and provides the
> unified interface required for the ARM64 TPH fix.
>
> ---
> Changes in v10:
> - Refine commit header&log according to Punit's and Bjorn's review
> - Split perf/arm_cspmu as a separate commit which address Punit's
>   review
>
> Changes in v9:
> - Address Bjorn's review: split commits to each platform so that make
>   them easy to review
>
> Changes in v8:
> - Moving arm64's get_cpu_for_acpi_id() to kernel/acpi.c which address
>   Jeremy's review
>
> Chengwen Feng (8):
>   arm64: acpi: Add acpi_get_cpu_uid() for unified ACPI CPU UID retrieval
>   LoongArch: Add acpi_get_cpu_uid() for unified ACPI CPU UID retrieval
>   RISC-V: ACPI: Add acpi_get_cpu_uid() for unified ACPI CPU UID
>     retrieval
>   x86/acpi: Add acpi_get_cpu_uid() for unified ACPI CPU UID retrieval
>   ACPI: Centralize acpi_get_cpu_uid() declaration in
>     include/linux/acpi.h
>   perf: arm_cspmu: Switch to acpi_get_cpu_uid() from
>     get_acpi_id_for_cpu()
>   ACPI: PPTT: Use acpi_get_cpu_uid() and remove get_acpi_id_for_cpu()
>   PCI/TPH: Pass ACPI Processor UID to Cache Locality _DSM
>
>  Documentation/PCI/tph.rst          |  4 +--
>  arch/arm64/include/asm/acpi.h      | 17 +---------
>  arch/arm64/kernel/acpi.c           | 30 ++++++++++++++++++
>  arch/loongarch/include/asm/acpi.h  |  5 ---
>  arch/loongarch/kernel/acpi.c       |  9 ++++++
>  arch/riscv/include/asm/acpi.h      |  4 ---
>  arch/riscv/kernel/acpi.c           | 16 ++++++++++
>  arch/riscv/kernel/acpi_numa.c      |  9 ++++--
>  arch/x86/include/asm/cpu.h         |  1 -
>  arch/x86/include/asm/smp.h         |  1 -
>  arch/x86/kernel/acpi/boot.c        | 20 ++++++++++++
>  arch/x86/xen/enlighten_hvm.c       |  5 +--
>  drivers/acpi/pptt.c                | 50 ++++++++++++++++++++++--------
>  drivers/acpi/riscv/rhct.c          |  7 ++++-
>  drivers/pci/tph.c                  | 16 +++++++---
>  drivers/perf/arm_cspmu/arm_cspmu.c |  6 ++--
>  include/linux/acpi.h               | 11 +++++++
>  include/linux/pci-tph.h            |  4 +--
>  18 files changed, 158 insertions(+), 57 deletions(-)
>
> --

It doesn't look like anyone has a particular heartburn related to this
series, so I could apply it in principle, but I'd appreciate some ACKs
from arch maintainers.

Why don't you resend it with all of the tags collected so far (and
please add x86@xxxxxxxxxx to the CC list)?