[PATCH 0/2] RFC: Move efi bgrt code out of arch/x86

[Bhupesh Sharma]

Hi Ard, Rafael

On Thu, Feb 16, 2017 at 5:14 AM, Rafael J. Wysocki <rjw at rjwysocki.net> wrote:
> On Wednesday, February 15, 2017 05:44:28 PM Ard Biesheuvel wrote:
>> Hello Bhupesh,
>>
>> On 15 February 2017 at 13:04, Bhupesh Sharma <bhsharma at redhat.com> wrote:
>> > This patchset presents a RFC approach to move the ACPI BGRT table
>> > handling related code out of 'arch/x86' and place it inside
>> > 'drivers/firmware/efi' so that it can be used to support
>> > ACPI BGRT table and BGRT logo across x86 and AARCH64 ARCHs.
>> >
>> > Note that this patchset is primarily tested on Qemu VMs for x86_64
>> > and AARCH64 environments, while I try to get my hands on a real
>> > AARCH64 hardware which supports a graphic card and whose boot firmware
>> > I can modify to support the ACPI BGRT table to be passed to the kernel.
>> >
>> > Here are some details/outputs about/from the test environment:
>> >
>> > AARCH64:
>> > ========
>> > 1. I used the latest Qemu (master branch) and compiled it for aarch64 with softmmu support.
>> >    Here is the command line I use to launch the same:
>> >
>> > # qemu-system-aarch64 -cpu cortex-a57 -M virt -m 2048 -bios QEMU_EFI.fd -kernel Image -initrd rootfs.cpio -serial stdio --append "acpi=force" -device virtio-gpu-pci
>> >
>> > where, QEMU_EFI.fd is the DEBUG build of EDK2 ArmVirtQemu.dsc (master branch)
>> >        rootfs.cpio is the AARCH64 build of Buildroot (Little Endian AARCH64)
>> >        -device virtio-gpu-pci provides the Graphical support required to have BGRT logo.
>> >
>> >
>> > 2. Here are some test results once Linux boots up, which show a valid BGRT table/logo being
>> >    seen by the kernel:
>> >
>> > # acpidump
>> > ...
>> >
>> > BGRT @ 0x0000000000000000
>> >   0000: 42 47 52 54 38 00 00 00 01 B4 49 4E 54 45 4C 20  BGRT8.....INTEL
>> >   0010: 45 44 4B 32 20 20 20 20 02 00 00 00 20 20 20 20  EDK2    ....
>> >   0020: 13 00 00 01 01 00 01 00 00 80 B0 BA 00 00 00 00  ................
>> >   0030: 2F 01 00 00 0F 01 00 00                          /.......
>> >
>> > # dmesg | grep -i BGRT
>> > [    0.000000] ACPI: BGRT 0x00000000B8640000 000038 (v01 INTEL  EDK2     00000002      01000013)
>> >
>> >
>> > # ls -lah /sys/firmware/acpi/bgrt/image
>> > -r--r--r--    1 root     root       32.9K Feb 15 11:27 /sys/firmware/acpi/bgrt/image
>> >
>> > x86:
>> > ====
>> > 1. I used the latest Qemu (master branch) and compiled it for x86.
>> >    Here is the command line I use to launch the same:
>> >
>> > # qemu-system-x86_64 -enable-kvm -sdl -m 2048 -vga std -boot c -cpu host -bios OVMF_CODE.fd -kernel bzImage -initrd rootfs.cpio -serial stdio
>> >
>> > where, OVMF_CODE.fd is the RELEASE build of EDK2 OvmfPkg (master branch)
>> >        rootfs.cpio is the x86_64 build of Buildroot
>> >
>> > 2. Similar test results are seen as noted for the AARCH64 case above, which show a valid BGRT table/logo being
>> >    seen by the kernel.
>> >
>> > Cc: Ard Biesheuvel <ard.biesheuvel at linaro.org>
>> > Cc: Ingo Molnar <mingo at kernel.org>
>> > Cc: Matt Fleming <matt at codeblueprint.co.uk>
>> > Cc: Dan Williams <dan.j.williams at intel.com>
>> > Cc: Dave Young <dyoung at redhat.com>
>> > Cc: Thomas Gleixner <tglx at linutronix.de>
>> > Cc: Mark Rutland <mark.rutland at arm.com>
>> > Cc: Will Deacon <will.deacon at arm.com>
>> >
>> > Bhupesh Sharma (2):
>> >   x86/efi-bgrt: Move efi-bgrt handling out of arch/x86
>> >   bgrt: Make ACPI BGRT parsing code common for ARCHs
>> >
>> >  arch/arm64/kernel/acpi.c                               | 3 +++
>> >  arch/x86/kernel/acpi/boot.c                            | 6 ------
>> >  arch/x86/platform/efi/Makefile                         | 1 -
>> >  drivers/acpi/Kconfig                                   | 2 +-
>> >  drivers/acpi/bgrt.c                                    | 6 ++++++
>> >  drivers/firmware/efi/Makefile                          | 1 +
>> >  {arch/x86/platform => drivers/firmware}/efi/efi-bgrt.c | 0
>> >  include/linux/efi-bgrt.h                               | 2 ++
>> >  8 files changed, 13 insertions(+), 8 deletions(-)
>> >  rename {arch/x86/platform => drivers/firmware}/efi/efi-bgrt.c (100%)
>> >
>>
>> These patches look fine to me, and I think we should be able to merge
>> them without any changes.
>>
>> Reviewed-by: Ard Biesheuvel <ard.biesheuvel at linaro.org>
>>
>> You only failed to cc the ACPI maintainers, please add Len and Rafael next time.

Oops. Will take care in future.

> No worries.
>
> The changes are fine by me.
>

Thanks Rafael and Ard.

Regards,
Bhupesh