Re: [RFC PATCH v3 0/4] TEE driver for AMD APUs

[Jens Wiklander <jens.wiklander@linaro.org>]

Hi Rijo,

On Thu, Dec 12, 2019 at 06:04:24PM +0530, Thomas, Rijo-john wrote:
> Hi Jens,
> 
> Please let me know if there are any comments for this patch series. I
> shall address them, if any, and post for next review.

This looks good, I have no further comments.

How do you intend to upstream this? There's the dependency towards "Add
TEE interface support to AMD Secure Processor driver"
(https://lkml.org/lkml/2019/12/4/42) to take into account too.

Thanks,
Jens

> 
> Thanks,
> Rijo
> 
> On 06/12/19 10:48 am, Rijo Thomas wrote:
> > This patch series introduces Trusted Execution Environment (TEE) driver
> > for AMD APU enabled systems. The TEE is a secure area of a processor which
> > ensures that sensitive data is stored, processed and protected in an
> > isolated and trusted environment. The AMD Secure Processor is a dedicated
> > processor which provides TEE to enable HW platform security. It offers
> > protection against software attacks generated in Rich Operating
> > System (Rich OS) such as Linux running on x86. The AMD-TEE Trusted OS
> > running on AMD Secure Processor allows loading and execution of security
> > sensitive applications called Trusted Applications (TAs). An example of
> > a TA would be a DRM (Digital Rights Management) TA written to enforce
> > content protection.
> > 
> > Linux already provides a tee subsystem, which is described in [1]. The tee
> > subsystem provides a generic TEE ioctl interface which can be used by user
> > space to talk to a TEE driver. AMD-TEE driver registers with tee subsystem
> > and implements tee function callbacks in an AMD platform specific manner.
> > 
> > The following TEE commands are recognized by AMD-TEE Trusted OS:
> > 1. TEE_CMD_ID_LOAD_TA : Load Trusted Application (TA) binary into TEE
> >    environment
> > 2. TEE_CMD_ID_UNLOAD_TA : Unload TA binary from TEE environment
> > 3. TEE_CMD_ID_OPEN_SESSION : Open session with loaded TA
> > 4. TEE_CMD_ID_CLOSE_SESSION : Close session with loaded TA
> > 5. TEE_CMD_ID_INVOKE_CMD : Invoke a command with loaded TA
> > 6. TEE_CMD_ID_MAP_SHARED_MEM : Map shared memory
> > 7. TEE_CMD_ID_UNMAP_SHARED_MEM : Unmap shared memory
> > 
> > Each command has its own payload format. The AMD-TEE driver creates a
> > command buffer payload for submission to AMD-TEE Trusted OS.
> > 
> > This patch series has a dependency on another patch set titled - Add TEE
> > interface support to AMD Secure Processor driver.
> > Link: https://lkml.org/lkml/2019/12/4/42
> > 
> > v3:
> > * Updated [1] with driver details
> > 
> > v2:
> > * Added a helper API in AMD Secure Processor driver, which can be
> >   called by AMD-TEE driver during module init to check if TEE is
> >   present on the device
> > * Added proper checks for parameter attribute variable
> > * Used tee_shm_pool_alloc() to allocate struct tee_shm_pool data structure
> > * Removed all references to tee_private.h header file in driver code,
> >   except for the file drivers/tee/amdtee/core.c. The driver loads TA binary
> >   by calling request_firmware(), which takes struct device* as one of its
> >   arguments. The device 'dev' field is part of struct tee_device, defined
> >   in tee_private.h
> > 
> > [1] https://www.kernel.org/doc/Documentation/tee.txt
> > 
> > Rijo Thomas (4):
> >   tee: allow compilation of tee subsystem for AMD CPUs
> >   tee: add AMD-TEE driver
> >   tee: amdtee: check TEE status during driver initialization
> >   Documentation: tee: add AMD-TEE driver details
> > 
> >  Documentation/tee.txt               |  81 ++++++
> >  drivers/crypto/ccp/tee-dev.c        |  11 +
> >  drivers/tee/Kconfig                 |   4 +-
> >  drivers/tee/Makefile                |   1 +
> >  drivers/tee/amdtee/Kconfig          |   8 +
> >  drivers/tee/amdtee/Makefile         |   5 +
> >  drivers/tee/amdtee/amdtee_if.h      | 183 +++++++++++++
> >  drivers/tee/amdtee/amdtee_private.h | 159 +++++++++++
> >  drivers/tee/amdtee/call.c           | 373 ++++++++++++++++++++++++++
> >  drivers/tee/amdtee/core.c           | 516 ++++++++++++++++++++++++++++++++++++
> >  drivers/tee/amdtee/shm_pool.c       |  93 +++++++
> >  include/linux/psp-tee.h             |  18 ++
> >  include/uapi/linux/tee.h            |   1 +
> >  13 files changed, 1451 insertions(+), 2 deletions(-)
> >  create mode 100644 drivers/tee/amdtee/Kconfig
> >  create mode 100644 drivers/tee/amdtee/Makefile
> >  create mode 100644 drivers/tee/amdtee/amdtee_if.h
> >  create mode 100644 drivers/tee/amdtee/amdtee_private.h
> >  create mode 100644 drivers/tee/amdtee/call.c
> >  create mode 100644 drivers/tee/amdtee/core.c
> >  create mode 100644 drivers/tee/amdtee/shm_pool.c
> > 
> > --
> > 1.9.1
> >