[PATCH v4 0/5] Add FF-A support in OP-TEE driver

Jens Wiklander
2021-08-19T11:07:11Z

Hi all,

This adds supports for the OP-TEE driver to communicate with secure world
using FF-A [1] as transport.

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. The functions relating to the SMC based ABI
are moved to smc_abi.c while the FF-A based ABI is added in a ffa_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. Note that it's only the old SMC based driver instance that
need device tree or ACPI to initialize. The FF-A based driver relies on the
FF-A bus instead.

This can be tested QEMU
The repo for SPMC at S-EL1 retrieved by
repo init -u https://github.com/jenswi-linaro/manifest.git -m
qemu_v8.xml -b ffav4_spmc
repo sync
# Then checkout the branch optee_ffa_v4 from
# git://git.linaro.org/people/jens.wiklander/linux-tee.git
# in the linux directory

To build do:
cd build
make toolchains
make all

To boot:
make run-only

Test with xtest, perhaps only with the command "xtest 1004" in case you're
not interested in too many tests.

Thanks,
Jens

[1] https://developer.arm.com/documentation/den0077/latest

v3->v4:
- Made a bit more RPC code common between the SMC and FF-A ABIs as
requested by Sumit.
- Replaced module_platform_driver() with module_init()/module_exit() as
described in the commit "optee: isolate smc abi".
- Applied Sumit's R-B for the commits "tee: add sec_world_id to struct
tee_shm", "optee: simplify optee_release()", and "optee: refactor driver
with internal callbacks"

v2->v3:
- Rebased on 5.14-rc2 which now have the FF-A patches merged
- Fixed a couple bugs in optee_shm_register() and optee_shm_unregister()
which where introduced in "optee: refactor driver with internal callbacks"
in previous the version.
- Separated SMC ABI specifics into smc_abi.c to keep it separated from
the FF-A ABI functions as requested by Sumit.
- Added the FF-A specifics in ffa_abi.c
- Provided an implementation for optee_ffa_remove()

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: isolate smc abi
optee: add FF-A support

drivers/tee/optee/Makefile | 7 +-
drivers/tee/optee/call.c | 415 ++-------
drivers/tee/optee/core.c | 685 ++-------------
drivers/tee/optee/ffa_abi.c | 907 ++++++++++++++++++++
drivers/tee/optee/optee_ffa.h | 153 ++++
drivers/tee/optee/optee_msg.h | 27 +-
drivers/tee/optee/optee_private.h | 162 +++-
drivers/tee/optee/rpc.c | 236 +-----
drivers/tee/optee/shm_pool.c | 89 --
drivers/tee/optee/shm_pool.h | 14 -
drivers/tee/optee/smc_abi.c | 1299 +++++++++++++++++++++++++++++
include/linux/tee_drv.h | 7 +-
12 files changed, 2665 insertions(+), 1336 deletions(-)
create mode 100644 drivers/tee/optee/ffa_abi.c
create mode 100644 drivers/tee/optee/optee_ffa.h
delete mode 100644 drivers/tee/optee/shm_pool.c
delete mode 100644 drivers/tee/optee/shm_pool.h
create mode 100644 drivers/tee/optee/smc_abi.c

--
2.31.1