Commit graph

8 commits

Author SHA1 Message Date
Theodore Karatapanis
707cdaf42e drivers/misc/optee: Expanded RPC support.
This commit expands RPC support for the OP-TEE driver using 2 files:
1) drivers/misc/optee_rpc.c
   * Add support for RPCs that can be handled directly by the kernel.
   * Can delegate RPC handling to optee_supplicant.c for RPCs that
     need userspace interaction.
2) drivers/misc/optee_supplicant.c
   * Enable communication between the userspace TEE supplicant and the
     kernel driver.

Additional changes were needed to the following files:
1) drivers/misc/optee.c
   * Add ioctls used SOLELY by the userspace TEE supplicant.
   * Register /dev/teepriv0 if the supplicant is enabled in Kconfig
   * Add OPTEE_ROLE_CA and OPTEE_ROLE_SUPPLICANT conditionals to
     differentiate paths, between a normal Client Application (CA)
     and the TEE supplicant.
   * Change some functions from static to "public" to reuse them
     in other C files.
   * Adjust optee_to/from_msg_param() to work with RPCs.

2) drivers/misc/optee_smc.c
   * Call the RPC handler from optee_rpc.c

3) drivers/misc/optee_msg.h
   * Add definition needed for RPCs

4) drivers/misc/tee.h
   * Add ioctl definitions
   * Add TEE_SHM_SUPP flag, checked when unregistering supplicant
     memory.

5) Documentation/guides/optee.rs
   * Add documentation for RPCs and the supplicant.

6) drivers/misc/{CMakeLists.txt, Make.defs}
   * Account for the new files.

7) drivers/misc/Kconfig
   * Add DEV_OPTEE_SUPPLICANT option to enable/disable the supplicant
     driver.

Signed-off-by: Theodore Karatapanis <tkaratapanis@census-labs.com>
2025-08-06 02:29:33 +08:00
Theodore Karatapanis
cbdd3ac39b drivers/misc/optee: Add virtual and physical address to sturct optee_shm
The VA -> PA translation must be performed once, at allocation time,
while the caller's virtual address space is known. If a second process
later tries to translate the same VA from a different mapping, the
calculated physical address can be wrong.

Signed-off-by: Theodore Karatapanis <tkaratapanis@census-labs.com>
2025-08-06 02:29:33 +08:00
George Poulios
c78e5b983a drivers/misc/optee_smc: Fix sched_yield() on flat builds
Previous change that introduced yielding upon OP-TEE
return with reason foreign interrupt, omitted to include
<sched.h>. This worked on kernel builds, but not on flat
builds. Include it.

Signed-off-by: George Poulios <gpoulios@census-labs.com>
2025-08-03 13:00:47 -03:00
George Poulios
199c301a8e drivers/misc/optee_smc: Explicitly yield during NW interrupts
CPU heavy OP-TEE calls would starve the Normal World tasks.
OP-TEE foreign interrupts were delivered to NW but we would
resume OP-TEE immediately without giving any potentially
unblocked tasks a chance to run. This would violate real-
time guarantees. Fix that by calling sched_yield() during
OP-TEE return with reason foreign interrupts.

Signed-off-by: George Poulios <gpoulios@census-labs.com>
2025-07-31 09:14:34 -03:00
George Poulios
589c0e13b8 drivers/misc/optee: Cache coherency when MMU is disabled
When the MMU is disabled (CONFIG_ARCH_USE_MMU=n) the
data passed back and forth with the TEE needs to be
synced from/to the cache, otherwise we get random data
in either world.

Fix this by cleaning before a call and invalidating after.
This has to be done both on the optee msg arg, and the shm
buffers therein. Cleaning and invalidating the page list
used to describe non-contiguous shm buffers did not seem
mandatory in my tests, but common sense says that it should
be, so we do that too.

This fix does not apply to the optee msg arg of the socket
transport (optee_socket.c), as that one _should_ be handled
by the socket send/recv methods. It does apply to all shm
buffers though, regardless of transport.

Signed-off-by: George Poulios <gpoulios@census-labs.com>
2025-07-16 15:35:00 +08:00
George Poulios
7f20487f56 drivers/misc/optee: Rename optee_shm_entry to optee_shm
This is no longer (exactly) the linked list entry that it
used to be, but rather an associated pointer in an idr tree
entry. Plain 'optee_shm' is more concise, and more appropriate.

Changes also reg_pair_to_uintptr() to reg_pair_to_ptr() for
better readability in invocations.

Signed-off-by: George Poulios <gpoulios@census-labs.com>
2025-05-13 10:14:01 +08:00
George Poulios
a2a689fee0 drivers/misc/optee: Fix GP API compatibility
Previous implementation was not compatible with GlobalPlatform
API in the following ways:
 - Registered mem IDs would begin from negatives when it should
   have been greater than or equal to 0
 - Register IOCTL would return 0 on success, when it should have
   been returning a file descriptor.
 - Register IOCTL would expect the user-space client to specify
   TEE_SHM_* flags dictating its behaviour when in fact, libteec
   never specifies flags.

This commit fixes all those issues. It uses nuttx/idr.h instead
of a linked list, and it uses `file_allocate` to provide file
descriptors for registered shared memory. Upon close(fd), the
memory is de-registered and freed accordingly. It also updates
the documentation accordingly.

Signed-off-by: George Poulios <gpoulios@census-labs.com>
2025-05-13 10:14:01 +08:00
George Poulios
b103a64a87 drivers/misc/optee: Add SMC backend for arm archs
So far NuttX has supported OP-TEE interfacing over
local and RPMsg sockets. This commit introduces support
for direct invocation of OP-TEE through arm SMCs. The
SMC transport is enabled through CONFIG_DEV_OPTEE_SMC.

This SMC implementation has been tested only with arm64,
OP-TEE rev 4.4.

Note that it does not support reverse direction RPCs,
i.e. from the Secure World to the Normal World to
something like optee supplicant. A basic RPC handling
skeleton is provided with implementation for some
basic functions (alloc/free mem, and foreign interrupts)
but no supplicant command handling.

(+one minor change s/parm/param in arch/arm64/include/syscall
to satisfy the spellchecker during PR)

Signed-off-by: George Poulios <gpoulios@census-labs.com>
2025-05-09 10:29:26 +08:00