Re: [PATCH v2 0/8] Trusted Execution Environment (TEE) driver for Qualcomm TEE (QTEE)

[Amirreza Zarrabi <quic_azarrabi@quicinc.com>]

On 2/5/2025 4:38 PM, Sumit Garg wrote:
> Hi Amirreza,
> 
> On Mon, 3 Feb 2025 at 08:14, Amirreza Zarrabi <quic_azarrabi@quicinc.com> wrote:
>>
>> This patch series introduces a Trusted Execution Environment (TEE)
>> driver for Qualcomm TEE (QTEE). QTEE enables Trusted Applications (TAs)
>> and services to run securely. It uses an object-based interface, where
>> each service is an object with sets of operations. Clients can invoke
>> these operations on objects, which can generate results, including other
>> objects. For example, an object can load a TA and return another object
>> that represents the loaded TA, allowing access to its services.
>>
>> Kernel and userspace services are also available to QTEE through a
>> similar approach. QTEE makes callback requests that are converted into
>> object invocations. These objects can represent services within the
>> kernel or userspace process.
>>
>> Note: This patch series focuses on QTEE objects and userspace services.
>>
>> Linux already provides a TEE subsystem, which is described in [1]. The
>> tee subsystem provides a generic ioctl interface, TEE_IOC_INVOKE, which
>> can be used by userspace to talk to a TEE backend driver. We extend the
>> Linux TEE subsystem to understand object parameters and an ioctl call so
>> client can invoke objects in QTEE:
>>
>>   - TEE_IOCTL_PARAM_ATTR_TYPE_OBJREF_*
>>   - TEE_IOC_OBJECT_INVOKE
>>
>> The existing ioctl calls TEE_IOC_SUPPL_RECV and TEE_IOC_SUPPL_SEND are
>> used for invoking services in the userspace process by QTEE.
>>
>> The TEE backend driver uses the QTEE Transport Message to communicate
>> with QTEE. Interactions through the object INVOKE interface are
>> translated into QTEE messages. Likewise, object invocations from QTEE
>> for userspace objects are converted into SEND/RECV ioctl calls to
>> supplicants.
>>
>> The details of QTEE Transport Message to communicate with QTEE is
>> available in [PATCH 10/10] Documentation: tee: Add Qualcomm TEE driver.
>>
>> You can run basic tests with following steps:
>> git clone https://github.com/quic/quic-teec.git
>> cd quic-teec
>> mkdir build
>> cmake .. -DCMAKE_TOOLCHAIN_FILE=CMakeToolchain.txt -DBUILD_UNITTEST=ON
>>
>> https://github.com/quic/quic-teec/blob/main/README.md lists dependancies
>> needed to build the above.
>>
>> This series has been tested for basic QTEE object invocations and
>> callback requests, including loading a TA and requesting services form
>> the TA.
> 
> Thanks for sharing these test user-space applications/libraries. Can I
> know which platforms are currently supported by this QTEE driver? I
> would like to run and understand the overall stack on a real device. I
> do have rb3, rb5 and db410c on my desk to test with.
> 
> Also, platform support is important information you should put in the
> cover letter as well as the QTEE documentation.
> 
> -Sumit
> 

I have tested it with sm8650-mtp. But would expect it to work with any platform.
I'll update the cover letter with the details :).

- Amir

>>
>> [1] https://www.kernel.org/doc/Documentation/tee.txt
>>
>> Signed-off-by: Amirreza Zarrabi <quic_azarrabi@quicinc.com>
>> ---
>> Changes in v2:
>> - Clean up commit messages and comments.
>> - Use better names such as ubuf instead of membuf or QCOMTEE prefix
>>   instead of QCOM_TEE, or names that are more consistent with other
>>   TEE-backend drivers such as qcomtee_context_data instead of
>>   qcom_tee_context.
>> - Drop the DTS patch and instantiate the device from the scm driver.
>> - Use a single structure for all driver's internal states.
>> - Drop srcu primitives and use the existing mutex for synchronization
>>   between the supplicant and QTEE.
>> - Directly use tee_context to track the lifetime of qcomtee_context_data.
>> - Add close_context() to be called when the user closes the tee_context.
>> - Link to v1: https://lore.kernel.org/r/20241202-qcom-tee-using-tee-ss-without-mem-obj-v1-0-f502ef01e016@quicinc.com
>>
>> Changes in v1:
>> - It is a complete rewrite to utilize the TEE subsystem.
>> - Link to RFC: https://lore.kernel.org/all/20240702-qcom-tee-object-and-ioctls-v1-0-633c3ddf57ee@quicinc.com
>>
>> ---
>> Amirreza Zarrabi (8):
>>       tee: allow a driver to allocate a tee_device without a pool
>>       tee: add close_context to TEE driver operation
>>       tee: add TEE_IOCTL_PARAM_ATTR_TYPE_UBUF
>>       tee: add TEE_IOCTL_PARAM_ATTR_TYPE_OBJREF
>>       firmware: qcom: scm: add support for object invocation
>>       tee: add Qualcomm TEE driver
>>       qcomtee: add primordial object
>>       Documentation: tee: Add Qualcomm TEE driver
>>
>>  Documentation/tee/index.rst            |   1 +
>>  Documentation/tee/qtee.rst             | 150 ++++++
>>  drivers/firmware/qcom/qcom_scm.c       | 128 ++++++
>>  drivers/firmware/qcom/qcom_scm.h       |   7 +
>>  drivers/tee/Kconfig                    |   1 +
>>  drivers/tee/Makefile                   |   1 +
>>  drivers/tee/qcomtee/Kconfig            |  10 +
>>  drivers/tee/qcomtee/Makefile           |  10 +
>>  drivers/tee/qcomtee/async.c            | 160 +++++++
>>  drivers/tee/qcomtee/call.c             | 741 ++++++++++++++++++++++++++++++
>>  drivers/tee/qcomtee/core.c             | 810 +++++++++++++++++++++++++++++++++
>>  drivers/tee/qcomtee/primordial_obj.c   |  65 +++
>>  drivers/tee/qcomtee/qcom_scm.c         |  36 ++
>>  drivers/tee/qcomtee/qcomtee_msg.h      | 234 ++++++++++
>>  drivers/tee/qcomtee/qcomtee_private.h  | 226 +++++++++
>>  drivers/tee/qcomtee/release.c          |  59 +++
>>  drivers/tee/qcomtee/shm.c              | 102 +++++
>>  drivers/tee/qcomtee/user_obj.c         | 712 +++++++++++++++++++++++++++++
>>  drivers/tee/tee_core.c                 | 121 ++++-
>>  drivers/tee/tee_private.h              |   6 -
>>  include/linux/firmware/qcom/qcom_scm.h |  27 ++
>>  include/linux/firmware/qcom/qcom_tee.h | 286 ++++++++++++
>>  include/linux/tee_core.h               |  15 +-
>>  include/linux/tee_drv.h                |  18 +
>>  include/uapi/linux/tee.h               |  54 ++-
>>  25 files changed, 3964 insertions(+), 16 deletions(-)
>> ---
>> base-commit: dab2734f8e9ecba609d66d1dd087a392a7774c04
>> change-id: 20241202-qcom-tee-using-tee-ss-without-mem-obj-362c66340527
>>
>> Best regards,
>> --
>> Amirreza Zarrabi <quic_azarrabi@quicinc.com>
>>