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2 Commits

Author SHA1 Message Date
Linus Torvalds a2d9214c73 TEE driver infrastructure and OP-TEE drivers
This branch introduces a generic TEE framework in the kernel, to handle
 trusted environemtns (security coprocessor or software implementations
 such as OP-TEE/TrustZone). I'm sending it separately from the other
 arm-soc driver changes to give it a little more visibility, once
 the subsystem is merged, we will likely keep this in the arm₋soc
 drivers branch or have the maintainers submit pull requests directly,
 depending on the patch volume.
 
 I have reviewed earlier versions in the past, and have reviewed
 the latest version in person during Linaro Connect BUD17.
 
 Here is my overall assessment of the subsystem:
 
 * There is clearly demand for this, both for the generic
   infrastructure and the specific OP-TEE implementation.
 
 * The code has gone through a large number of reviews,
   and the review comments have all been addressed, but
   the reviews were not coming up with serious issues any more
   and nobody volunteered to vouch for the quality.
 
 * The user space ioctl interface is sufficient to work with the
   OP-TEE driver, and it should in principle work with other
   TEE implementations that follow the GlobalPlatform[1] standards,
   but it might need to be extended in minor ways depending on
   specific requirements of future TEE implementations
 
 * The main downside of the API to me is how the user space
   is tied to the TEE implementation in hardware or firmware,
   but uses a generic way to communicate with it. This seems
   to be an inherent problem with what it is trying to do,
   and I could not come up with any better solution than what
   is implemented here.
 
 For a detailed history of the patch series, see
 https://lkml.org/lkml/2017/3/10/1277
 
 Conflicts: needs a fixup after the drm tree was merged, see
 https://patchwork.kernel.org/patch/9691679/
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Merge tag 'armsoc-tee' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull TEE driver infrastructure and OP-TEE drivers from Arnd Bergmann:
 "This introduces a generic TEE framework in the kernel, to handle
  trusted environemtns (security coprocessor or software implementations
  such as OP-TEE/TrustZone). I'm sending it separately from the other
  arm-soc driver changes to give it a little more visibility, once the
  subsystem is merged, we will likely keep this in the arm₋soc drivers
  branch or have the maintainers submit pull requests directly,
  depending on the patch volume.

  I have reviewed earlier versions in the past, and have reviewed the
  latest version in person during Linaro Connect BUD17.

  Here is my overall assessment of the subsystem:

   - There is clearly demand for this, both for the generic
     infrastructure and the specific OP-TEE implementation.

   - The code has gone through a large number of reviews, and the review
     comments have all been addressed, but the reviews were not coming
     up with serious issues any more and nobody volunteered to vouch for
     the quality.

   - The user space ioctl interface is sufficient to work with the
     OP-TEE driver, and it should in principle work with other TEE
     implementations that follow the GlobalPlatform[1] standards, but it
     might need to be extended in minor ways depending on specific
     requirements of future TEE implementations

   - The main downside of the API to me is how the user space is tied to
     the TEE implementation in hardware or firmware, but uses a generic
     way to communicate with it. This seems to be an inherent problem
     with what it is trying to do, and I could not come up with any
     better solution than what is implemented here.

  For a detailed history of the patch series, see

    https://lkml.org/lkml/2017/3/10/1277"

* tag 'armsoc-tee' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  arm64: dt: hikey: Add optee node
  Documentation: tee subsystem and op-tee driver
  tee: add OP-TEE driver
  tee: generic TEE subsystem
  dt/bindings: add bindings for optee
2017-05-10 11:20:09 -07:00
Jens Wiklander 967c9cca2c tee: generic TEE subsystem
Initial patch for generic TEE subsystem.
This subsystem provides:
* Registration/un-registration of TEE drivers.
* Shared memory between normal world and secure world.
* Ioctl interface for interaction with user space.
* Sysfs implementation_id of TEE driver

A TEE (Trusted Execution Environment) driver is a driver that interfaces
with a trusted OS running in some secure environment, for example,
TrustZone on ARM cpus, or a separate secure co-processor etc.

The TEE subsystem can serve a TEE driver for a Global Platform compliant
TEE, but it's not limited to only Global Platform TEEs.

This patch builds on other similar implementations trying to solve
the same problem:
* "optee_linuxdriver" by among others
  Jean-michel DELORME<jean-michel.delorme@st.com> and
  Emmanuel MICHEL <emmanuel.michel@st.com>
* "Generic TrustZone Driver" by Javier González <javier@javigon.com>

Acked-by: Andreas Dannenberg <dannenberg@ti.com>
Tested-by: Jerome Forissier <jerome.forissier@linaro.org> (HiKey)
Tested-by: Volodymyr Babchuk <vlad.babchuk@gmail.com> (RCAR H3)
Tested-by: Scott Branden <scott.branden@broadcom.com>
Reviewed-by: Javier González <javier@javigon.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
2017-03-09 15:42:33 +01:00