Hi Jens,
This patch-set skipped my inbox as I was not on the CC list. So while reading through ML archives, I found it.
On Thu, 27 May 2021 at 13:45, Jens Wiklander jens.wiklander@linaro.org wrote:
Hi all,
This adds supports for the OP-TEE driver to communicate with secure world using FF-A [1] as transport.
These patches are based on the FF-A v7 patch set by Sudeep Holla [2] [3].
I could see the FF-A driver support merged upstream. Is this patch-set directly applicable on the upstream kernel? If yes, can you also share steps to test it on Qemu?
There is one change to the TEE subsystem with "tee: add sec_world_id to struct tee_shm" to add support for holding globally unique handle assigned by the FF-A. This is a field that I believe could useful for the AMDTEE driver too.
For communication the OP-TEE message protocol is still used, but with a new type of memory reference, struct optee_msg_param_fmem, to carry the information needed by FF-A. The OP-TEE driver is refactored internally with to sets of callbacks, one for the old SMC based communication and another set with FF-A as transport.
Since now we have two ABIs towards secure world: - OP-TEE ABI - FF-A ABI
I think it would be better to have ABI specific APIs separated from core.c to have a clear view of abstraction. How about new file names as: - optee_{msg/abi}.c - ffa_{msg/abi}.c
There is also a difference in how the drivers are instantiated. With the SMC based transport we have a platform driver, module_platform_driver(), today which we're keeping as is for this configuration. In a FF-A system we have a FF-A driver, module_ffa_driver(), instead.
The OP-TEE driver can be compiled for both targets at the same time and it's up to runtime configuration (device tree or ACPI) to decide how it's initialized.
Can you elaborate on different device tree or ACPI configuration? AFAIR, FF-A utilizes bus enumeration to scan OP-TEE UUID.
-Sumit
Thanks, Jens
[1] https://developer.arm.com/documentation/den0077/latest [2] https://lore.kernel.org/linux-arm-kernel/20210521151033.181846-1-sudeep.holl... [3] git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux.git v5.13/ffa
v1->v2:
- Rebased to the FF-A v7 patch
- Fixed a couple of reports from kernel test robot lkp@intel.com
Jens Wiklander (5): tee: add sec_world_id to struct tee_shm optee: simplify optee_release() optee: refactor driver with internal callbacks optee: add a FF-A memory pool optee: add FF-A support
drivers/tee/optee/call.c | 325 +++++++++++--- drivers/tee/optee/core.c | 689 ++++++++++++++++++++++++++---- drivers/tee/optee/optee_ffa.h | 153 +++++++ drivers/tee/optee/optee_msg.h | 27 +- drivers/tee/optee/optee_private.h | 88 +++- drivers/tee/optee/rpc.c | 137 +++++- drivers/tee/optee/shm_pool.c | 65 ++- drivers/tee/optee/shm_pool.h | 1 + include/linux/tee_drv.h | 7 +- 9 files changed, 1326 insertions(+), 166 deletions(-) create mode 100644 drivers/tee/optee/optee_ffa.h
-- 2.25.1
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