Re: [PATCH v4 00/22] arm64: FF-A runtime transport for EFI variables

Hi Peter,

>
> Hi Ilias,
>
> > I'll be off next week so this is going to take some time for a wider review.
> > Since this is quite a lot of code to review, I'd prefer being able to
> > test all of the cases to make sure nothing breaks and add more
> > selftests in the future. I don't have access to a Corstone-1000.  The
>
> You can get the Corstone-1K FVP here:
> https://corstone1000.docs.arm.com/en/corstone1000-2026.05/index.html
>

Ok thanks. I'd still prefer to have this on QEMU since we can
reproduce all the cases there (variables in RPMB as of today + the
FF-A variant). Even if we do use the FVP, I'd like to have information
of how to build & test this as part of the cover letter, since Tom
includes that in pull requests.

Cheers
/Ilias
> > latest version of QEMU do support emulating an RPMB device. Would the
> > changes above work with with an SP, QEMU RPMB and OP-TEE?
> >
> > Thanks
> > /Ilias
> >
> > On Wed, 29 Jul 2026 at 11:51, Harsimran Singh Tungal
> > <[email protected]> wrote:
> > >
> > > Hi all,
> > >
> > > This series adds FF-A runtime transport support so EFI variable runtime
> > > services can communicate with the secure world after ExitBootServices().
> > > It also extends tests, documentation, and Corstone-1000 configuration to
> > > validate the runtime path and keep boot-time behavior aligned with the
> > > runtime flow.
> > >
> > > Changes in this series:
> > > - Add EFI runtime-safe memset helper and FF-A runtime transport support.
> > > - Add runtime-safe FF-A direct-message handling and ExitBootServices setup.
> > > - Implement FF-A runtime communication in the EFI variable TEE backend.
> > > - Enable EFI runtime SetVariable(), GetVariable(), GetNextVariableName(),
> > >   and QueryVariableInfo() over the FF-A transport.
> > > - Add sandbox FF-A runtime transport tests.
> > > - Extend EFI selftests for runtime variables and enable bootefi selftest
> > >   on Corstone-1000.
> > > - Document the FF-A runtime transport and runtime-variable selftest flow.
> > >
> > > Changes in v4:
> > >
> > > Address Ilias Apalodimas's review comments:
> > > - Split FF-A bus runtime support into smaller patches covering runtime
> > >   private data, SMC invocation, direct-message helpers, boot-time reuse,
> > >   and ExitBootServices setup.
> > > - Split the ARMv8 cache range-maintenance runtime annotations into a
> > >   separate patch.
> > > - Split the EFI variable TEE runtime SetVariable(), GetVariable(),
> > >   GetNextVariableName(), and QueryVariableInfo() support into separate
> > >   patches.
> > > - Replace MM SP status macros with an enum.
> > > - Keep OP-TEE as the runtime fallback when FF-A runtime mode is not
> > >   enabled.
> > >
> > > Other changes:
> > > - Rebased the series onto current U-Boot master.
> > >
> > > Changes in v3:
> > >
> > > Address Simon Glass's review comments:
> > > - Move FF-A ExitBootServices event registration to the end of probe and
> > >   clean up RX/TX buffer handling on failure.
> > > - Rename FF-A runtime-context helpers to the ffa_runtime_context_* form.
> > > - Rework FF-A/MM cache maintenance to cover only rounded request and
> > >   response ranges.
> > > - Add SetVirtualAddressMap handling for the FF-A shared buffer.
> > > - Document FF-A shared-buffer ownership and alignment assumptions.
> > > - Add EFIAPI to the TEE runtime GetVariable and GetNextVariableName
> > >   entry points.
> > > - Tighten sandbox FF-A runtime tests and reset runtime state between
> > >   test cases.
> > > - Update FF-A and bootefi documentation for the runtime transport and
> > >   split runtime-variable selftests.
> > > - Rework commit messages to drop redundant information.
> > >
> > > Address Ilias Apalodimas's review comments:
> > > - Keep efi_var_common.c unchanged and drop commit 6 from v2 patchset.
> > > - Rename the TEE/FF-A runtime handlers to the *_int_runtime form.
> > > - Remove log_*() calls from __efi_runtime FF-A/MM communication paths.
> > >
> > > Other:
> > > - Fix FF-A memory-share sender_id to use the runtime private endpoint
> > >   ID after rebasing.
> > > - Fix the expected QueryVariableInfo() return status for the
> > >   TEE-backed runtime selftest path.
> > >
> > >
> > > Changes in v2:
> > >
> > > Address Simon Glass's review comments:
> > > - Fix efi_memset_runtime() style, declaration, and byte cast
> > > - Tighten the FF-A runtime context failure path, clean up arm-ffa-runtime.c
> > >   style issues, and move ExitBootServices event registration earlier in probe
> > > - Add shared-buffer bounds/alignment checks, and tightening comments/kernel-doc
> > > - Document the FF-A shared buffer cacheline-alignment requirement and add
> > >   BUILD_BUG_ON() checks for the address
> > > - Cache attributes before the shared buffer is reused, moving the read-only
> > >   check earlier, and split the u16_strsize() related change in separate patch
> > > - Reword commit messages for the runtime helper relocation
> > > - Rework the non-volatile runtime variable selftest into setup/verify phases
> > > - Extend the sandbox FF-A runtime tests with no-context coverage,
> > >   runtime-context reset, and separate errno-mapping coverage
> > > - Refresh the FF-A runtime transport and bootefi documentation
> > > - Drop patch 12 in v1, as ffa_mm_communicate handles both runtime and
> > >   boottime capabilities in v2
> > > - Squash patch 8 and patch 9 from v1
> > >
> > > Address Ilias Apalodimas's review comments:
> > > - Reuse common MM SP error mapping for boot and runtime paths
> > > - Rename runtime-phase tracking to reflect the ExitBootServices transition
> > > - Collapse duplicated boot-time and runtime MM communication helpers into common
> > >   implementations
> > > - Keep the arm64 cache-maintenance path runtime-safe
> > > - Move FF-A shared-buffer runtime memory-map registration to the end of
> > >   variable-service initialization
> > >
> > > Link to v3: https://lore.kernel.org/u-boot/[email protected]/
> > > Link to v2: https://lore.kernel.org/u-boot/[email protected]/
> > > Link to v1: https://lore.kernel.org/u-boot/[email protected]/
> > >
> > > Harsimran Singh Tungal (22):
> > >   efi_loader: add runtime memset helper
> > >   arm-ffa: store boot-discovered runtime data separately
> > >   arm-ffa: add runtime-safe FF-A SMC wrapper
> > >   arm-ffa: add runtime direct-message support
> > >   arm-ffa: reuse direct-message helper at boot time
> > >   arm-ffa: enable runtime context at ExitBootServices
> > >   arm: cache: keep range maintenance available at EFI runtime
> > >   efi_loader: add MM SP status mapping for FF-A variables
> > >   efi_loader: make MM transport selection runtime-safe
> > >   efi_loader: make FF-A MM SP notification runtime-safe
> > >   efi_loader: make FF-A MM communication runtime-safe
> > >   efi_loader: reserve FF-A shared buffer for runtime variables
> > >   efi_loader: enable TEE runtime SetVariable() over FF-A
> > >   efi_loader: enable TEE runtime GetVariable() over FF-A
> > >   efi_loader: enable TEE runtime GetNextVariableName() over FF-A
> > >   efi_loader: enable TEE runtime QueryVariableInfo() over FF-A
> > >   charset: mark u16_strsize() as __efi_runtime
> > >   corstone1000: enable bootefi selftest
> > >   efi: selftest: add runtime variable tests with non-volatile storage
> > >   test: dm: add sandbox FF-A runtime transport tests
> > >   doc: arm64: document FF-A runtime path for EFI variables
> > >   doc: bootefi: note two-phase runtime variables selftest
> > >
> > >  arch/arm/cpu/armv8/cache.S                    |   8 +
> > >  arch/arm/cpu/armv8/cache_v8.c                 |  13 +-
> > >  arch/sandbox/include/asm/sandbox_arm_ffa.h    |  16 +-
> > >  configs/corstone1000_defconfig                |   3 +
> > >  doc/arch/arm64.ffa.rst                        |  88 ++-
> > >  doc/usage/cmd/armffa.rst                      |  11 +
> > >  doc/usage/cmd/bootefi.rst                     |  31 +
> > >  drivers/firmware/arm-ffa/Kconfig              |  11 +
> > >  drivers/firmware/arm-ffa/Makefile             |   4 +-
> > >  drivers/firmware/arm-ffa/arm-ffa-runtime.c    | 294 +++++++
> > >  drivers/firmware/arm-ffa/arm-ffa-uclass.c     | 114 +--
> > >  drivers/firmware/arm-ffa/arm-ffa.c            |  16 +-
> > >  drivers/firmware/arm-ffa/ffa-emul-uclass.c    |  49 +-
> > >  include/arm_ffa.h                             |  16 +-
> > >  include/arm_ffa_priv.h                        |  22 +-
> > >  include/arm_ffa_runtime.h                     | 191 +++++
> > >  include/efi_loader.h                          |   3 +
> > >  lib/charset.c                                 |   2 +-
> > >  lib/efi_loader/Kconfig                        |   4 +
> > >  lib/efi_loader/efi_runtime.c                  |  20 +
> > >  lib/efi_loader/efi_variable_tee.c             | 739 +++++++++++++++---
> > >  .../efi_selftest_variables_runtime.c          | 715 +++++++++++------
> > >  test/dm/Makefile                              |   3 +-
> > >  test/dm/ffa.c                                 |   6 +-
> > >  test/dm/ffa_runtime.c                         | 123 +++
> > >  25 files changed, 2004 insertions(+), 498 deletions(-)
> > >  create mode 100644 drivers/firmware/arm-ffa/arm-ffa-runtime.c
> > >  create mode 100644 include/arm_ffa_runtime.h
> > >  create mode 100644 test/dm/ffa_runtime.c
> > >
> > > --
> > > 2.34.1
> > >