Re: [PATCH v6 0/4] Introduce TEE bus driver framework
From: Ard Biesheuvel
Date: Tue Feb 12 2019 - 06:06:00 EST
On Tue, 29 Jan 2019 at 06:50, Sumit Garg <sumit.garg@xxxxxxxxxx> wrote:
> This series introduces a generic TEE bus driver concept for TEE based
> kernel drivers which would like to communicate with TEE based devices/
> Patch #1 adds TEE bus concept where devices/services are identified via
> Universally Unique Identifier (UUID) and drivers register a table of
> device UUIDs which they can support. This concept also allows for device
> enumeration to be specific to corresponding TEE implementation like
> OP-TEE etc.
> Patch #2 adds supp_nowait flag for non-blocking requests arising via
> TEE internal client interface.
> Patch #3 adds TEE bus device enumeration support for OP-TEE. OP-TEE
> provides a pseudo TA to enumerate TAs which can act as devices/services
> for TEE bus.
> Patch #4 adds OP-TEE based hwrng driver which act as TEE bus driver.
> On ARM SoC's with TrustZone enabled, peripherals like entropy sources
> might not be accessible to normal world (linux in this case) and rather
> accessible to secure world (OP-TEE in this case) only. So this driver
> aims to provides a generic interface to OP-TEE based random number
> generator service.
> Example case is Developerbox based on Socionext's Synquacer SoC 
> which provides 7 thermal sensors accessible from secure world only which
> could be used as entropy sources (thermal/measurement noise).
>  https://www.96boards.org/product/developerbox/
> Changes in v6:
> 1. Incorporate some nitpicks in patch #1 and #3.
> 2. Bundle all statics in a data structure in patch #4 and use dev_*
> instead of pr_*.
> 3. Add reviewed-by tags for patch #1, #2 and #3.
> Changes in v5:
> 1. Add support in module device table for TEE bus devices.
> 2. Correct license for optee-rng module.
> Changes in v4:
> 1. Use typedef instead of single member tee_client_device_id struct.
> 2. Incorporate TEE bus nitpicks.
> Changes in v3:
> 1. Fixed bus error path in Patch #1.
> 2. Reversed order of Patch #2 and #3.
> 3. Fixed miscellaneous syntax comments and memory leak.
> 4. Added comments in Patch #2 for supp_nowait flag.
> Changes in v2:
> Based on review comments, the scope of this series has increased as
> 1. Added TEE bus driver framework.
> 2. Added OP-TEE based device enumeration.
> 3. Register optee-rng driver as TEE bus driver.
> 4. Removed DT dependency for optee-rng device UUID.
> 5. Added supp_nowait flag.
> Sumit Garg (4):
> tee: add bus driver framework for TEE based devices
> tee: add supp_nowait flag in tee_context struct
> tee: optee: add TEE bus device enumeration support
> hwrng: add OP-TEE based rng driver
For this series
Tested-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
although I had to load optee.ko manually in order for the udev
autoload of optee_rng to trigger. Not sure where the discussion went
last time, but could we please add "linaro,optee-tz" as a DT modalias
to the optee.ko module in any case?
> MAINTAINERS | 5 +
> drivers/char/hw_random/Kconfig | 15 ++
> drivers/char/hw_random/Makefile | 1 +
> drivers/char/hw_random/optee-rng.c | 298 +++++++++++++++++++++++++++++++++++++
> drivers/tee/optee/Makefile | 1 +
> drivers/tee/optee/core.c | 4 +
> drivers/tee/optee/device.c | 155 +++++++++++++++++++
> drivers/tee/optee/optee_private.h | 3 +
> drivers/tee/optee/supp.c | 10 +-
> drivers/tee/tee_core.c | 67 ++++++++-
> include/linux/mod_devicetable.h | 9 ++
> include/linux/tee_drv.h | 38 ++++-
> scripts/mod/devicetable-offsets.c | 3 +
> scripts/mod/file2alias.c | 19 +++
> 14 files changed, 622 insertions(+), 6 deletions(-)
> create mode 100644 drivers/char/hw_random/optee-rng.c
> create mode 100644 drivers/tee/optee/device.c