[PATCH v4 00/13] UEFI boot and runtime services support for 32-bit ARM

Wed Dec 2 06:53:55 PST 2015

On 30 November 2015 at 13:28, Ard Biesheuvel <ard.biesheuvel at linaro.org> wrote:
> This series adds support for booting the 32-bit ARM kernel directly from
> UEFI firmware using a builtin UEFI stub. It mostly reuses refactored arm64
> code, and the differences (primarily the PE/COFF header and entry point and
> the efi_create_mapping() implementation) are split out into arm64 and ARM
> versions.
>
> Since I did not receive any further comments in reply to v3 from the people who
> commented on v2, I think this series in now in sufficient shape to be pulled.
> Note that patch #1 touches mm/memblock.c and include/linux/memblock.h, for which
> get_maintainer.pl does not provide a maintainer, so it has been cc'ed to various
> past editors of those files, and to the linux-mm mailing list.
>
> Since the series affects both arm64 and ARM, it is up to the maintainers to let
> me know how and when they wish to proceed with this. My suggestion would be to
> send out pull request for patches #1 - #5 to the arm64 maintainer, and for the
> whole series to the ARM maintainer. This should keep any conflicts on either
> side confined to the respective maintainer tree, rather then propagating all the
> way to -next.
>
> For the result of regression testing against these patches, please refer to the
> following links for build and boot reports (respectively) generated by
> kernelci.org (thanks guys).
>
> http://kernelci.org/build/ardb/kernel/v4.4-rc3-13-g9e4dc4695ba0/
> http://kernelci.org/boot/all/job/ardb/kernel/v4.4-rc3-13-g9e4dc4695ba0/
>
> Note that the above is regression testing only, as kernelci does not yet support
> booting 32-bit ARM targets in EFI mode. This functionality has been verified
> independently (on actual hardware) by Ryan Harkin <ryan.harkin at linaro.org>, who
> has kindly given his Tested-by for the ARM patches in this series (#6 - #13)
>
> Please find instructions for duplicating the EFI boot testing using QEMU at the
> end of this email.
>
> Changes since v3:
> - rebased onto v4.4-rc3
> - minor change in #13: use 'dram_base + MAX_UNCOMP_KERNEL_SIZE' as preferred
>   base for the allocation that holds the relocated compressed kernel image
>   (the former value of 0x0 is usually not covered by DRAM, resulting in the
>   value above to be used anyway)
> - added Reviewed-by from Matt Fleming
> - added Tested-by from Ryan Harkin (#6 - #13)
>
> Changes since v2:
> - Some issues pointed out by Russell and Matt that were not introduced by this
>   series but merely became apparent due to the code movement in patch #4 have
>   been addressed in a separate 2-piece series I sent out this morning. This v3
>   is rebased on top of those patches.
> - Added a patch (#9) that adds support for creating non-global mappings. This
>   addresses a concern raised by Russell in response to v2 where the use of
>   global mappings combined with a flawed context switch and TBL flush sequence
>   could result in memory corruption.
> - Rebased onto v4.4-rc2
>
> Changes since v1:
> - The primary difference between this version and the first one is that all
>   prerequisites have either been merged, dropped for now (early FDT handling)
>   or folded into this series (MEMBLOCK_NOMAP). IOW, this series can be applied
>   on top of v4.4-rc1 directly.
> - Dropped handling of UEFI permission bits. The reason is that the UEFIv2.5
>   approach (EFI_PROPERTIES_TABLE) is flawed, and will be replaced by something
>   better in the next version of the spec.
>
> Patch #1 adds support for the MEMBLOCK_NOMAP attribute to the generic memblock
> code. Its purpose is to annotate memory regions as normal memory even if they
> are removed from the kernel direct mapping.
>
> Patch #2 implements MEMBLOCK_NOMAP support for arm64
>
> Patch #3 updates the EFI init code to remove UEFI reserved regions and regions
> used by runtime services from the kernel direct mapping
>
> Patch #4 splits off most of arch/arm64/kernel/efi.c into arch agnostic files
> arm-init.c and arm-runtime.c under drivers/firmware/efi.
>
> Patch #5 refactors the code split off in patch #1 to isolate the arm64 specific
> pieces, and change a couple of arm64-isms that ARM handles slightly differently.
>
> Patch #6 enables the generic early_ioremap and early_memremap implementations
> for ARM. It reuses the kmap fixmap region, which is not used that early anyway.
>
> Patch #7 splits off the core functionality of create_mapping() into a new
> function __create_mapping() that we can reuse for mapping UEFI runtime regions.
>
> Patch #8 factors out the early_alloc() routine so we can invoke __create_mapping
> using another (late) allocator.
>
> Patch #9 adds support to __create_mapping() for creating non-global translation
> table entries. (new in v3)
>
> Patch #10 implements create_mapping_late() that uses a late allocator.
>
> Patch #11 implements MEMBLOCK_NOMAP support for ARM
>
> Patch #12 implements the UEFI support in the kernel proper to probe the UEFI
> memory map and map the runtime services.
>
> Patch #13 ties together all of the above, by implementing the UEFI stub, and
> introducing the Kconfig symbols that allow all of this to be built.
>
>
> Ard Biesheuvel (12):
>   mm/memblock: add MEMBLOCK_NOMAP attribute to memblock memory table
>   arm64: only consider memblocks with NOMAP cleared for linear mapping
>   arm64/efi: mark UEFI reserved regions as MEMBLOCK_NOMAP
>   arm64/efi: split off EFI init and runtime code for reuse by 32-bit ARM
>   arm64/efi: refactor EFI init and runtime code for reuse by 32-bit ARM
>   ARM: add support for generic early_ioremap/early_memremap
>   ARM: split off core mapping logic from create_mapping
>   ARM: factor out allocation routine from __create_mapping()
>   ARM: add support for non-global kernel mappings
>   ARM: implement create_mapping_late() for EFI use
>   ARM: only consider memblocks with NOMAP cleared for linear mapping
>   ARM: wire up UEFI init and runtime support
>
> Roy Franz (1):
>   ARM: add UEFI stub support
>
>  arch/arm/Kconfig                          |  20 ++
>  arch/arm/boot/compressed/Makefile         |   4 +-
>  arch/arm/boot/compressed/efi-header.S     | 130 ++++++++
>  arch/arm/boot/compressed/head.S           |  54 +++-
>  arch/arm/boot/compressed/vmlinux.lds.S    |   7 +
>  arch/arm/include/asm/Kbuild               |   1 +
>  arch/arm/include/asm/efi.h                |  83 +++++
>  arch/arm/include/asm/fixmap.h             |  29 +-
>  arch/arm/include/asm/mach/map.h           |   2 +
>  arch/arm/include/asm/mmu_context.h        |   2 +-
>  arch/arm/kernel/Makefile                  |   1 +
>  arch/arm/kernel/efi.c                     |  38 +++
>  arch/arm/kernel/setup.c                   |  10 +-
>  arch/arm/mm/init.c                        |   5 +-
>  arch/arm/mm/ioremap.c                     |   9 +
>  arch/arm/mm/mmu.c                         | 128 +++++---
>  arch/arm64/include/asm/efi.h              |   9 +
>  arch/arm64/kernel/efi.c                   | 334 +-------------------
>  arch/arm64/mm/init.c                      |   2 +-
>  arch/arm64/mm/mmu.c                       |   2 +
>  drivers/firmware/efi/Makefile             |   4 +
>  drivers/firmware/efi/arm-init.c           | 209 ++++++++++++
>  drivers/firmware/efi/arm-runtime.c        | 135 ++++++++
>  drivers/firmware/efi/efi.c                |   2 +
>  drivers/firmware/efi/libstub/Makefile     |   9 +
>  drivers/firmware/efi/libstub/arm-stub.c   |   4 +-
>  drivers/firmware/efi/libstub/arm32-stub.c |  85 +++++
>  include/linux/memblock.h                  |   8 +
>  mm/memblock.c                             |  28 ++
>  29 files changed, 986 insertions(+), 368 deletions(-)
>  create mode 100644 arch/arm/boot/compressed/efi-header.S
>  create mode 100644 arch/arm/include/asm/efi.h
>  create mode 100644 arch/arm/kernel/efi.c
>  create mode 100644 drivers/firmware/efi/arm-init.c
>  create mode 100644 drivers/firmware/efi/arm-runtime.c
>  create mode 100644 drivers/firmware/efi/libstub/arm32-stub.c
>
>
> Testing instructions
> ====================
>
> 1. Download a prebuilt firmware binary:
> http://snapshots.linaro.org/components/kernel/leg-virt-tianocore-edk2-upstream/latest/QEMU-ARM/RELEASE_GCC49/QEMU_EFI.img.gz
>
> 2. Unzip it
> gunzip QEMU_EFI.img.gz
>
> 3. Download a prebuilt kernel binary (non-LPAE or LPAE, respectively):
> http://storage.kernelci.org/ardb/v4.4-rc3-13-g9e4dc4695ba0/arm-multi_v7_defconfig+CONFIG_EFI=y/zImage
> http://storage.kernelci.org/ardb/v4.4-rc3-13-g9e4dc4695ba0/arm-multi_v7_defconfig+CONFIG_EFI=y+CONFIG_ARM_LPAE=y/zImage
>
> 4. Run it
> qemu-system-arm -M virt -m 512 -nographic \
>         -bios QEMU_EFI.img -kernel zImage \
>         -append 'earlycon efi=debug console=ttyAMA0'
>
> (Ctrl-A Ctrl-X to quit)

Please note that combining -bios and -kernel as I do above requires
QEMU v2.3 or later.