The result of `mctp_pktbuf_alloc` wasn't being checked on both
controller and target. While a simple check is enough for the
controller, the target fix is a bit more involved.
As the target was allocating the buffer when it received the length
of the message on its pseudoregister, a buggy controller could write
this more than once, making previous allocations leak. This is solved by
only noting the size of the message written to the pseudoregister, and
doing the allocation when the first byte of the message was received.
This flow also ensures that a buggy controller can't skip sending the
length of the message, as this will result in a zero-sized MCTP packet,
which will be handled by libmctp.
Signed-off-by: Ederson de Souza <ederson.desouza@intel.com>
Signed-off-by: David Brown <david.brown@linaro.org>
Assisted-By: Claude:opus-4.8
Adds support for the USB device binding for MCTP. Binding created based on
the DMTF specification for USB Transport Binding. The overall design of
this binding follows the existing UART and I2C+GPIO bindings that already
exist in Zephyr.
Signed-off-by: Eric Ocasio <eric.ocasio@nxp.com>
Adds the missing sample.yaml's for building these in CI and with
twister.
Fixes a build issue that came up along the way.
Signed-off-by: Tom Burdick <thomas.burdick@intel.com>
Adds a I2C+GPIO Target device binding for MCTP communication over I2C.
The binding requires an i2c bus and gpio pin, along with a specified I2C
and endpoint address pair. These are then used to create an MCTP binding
which can be used to communicate in a peer to peer manner among other
MCTP endpoints.
Each message transmit signals to the bus controller using a GPIO logical
high and is unset on transmission completion. Pending transmitters are
queued using a semaphore avoiding memcpy being needed to asynchronously
transmit mctp pktbufs.
Signed-off-by: Tom Burdick <thomas.burdick@intel.com>
Adds a custom MCTP binding for an I2C bus controller using GPIO signaling
for write requests rather than mode switching.
This binding operates a lot like the I3C binding specification DMTF has
for MCTP. The controller expects to receive interrupts (from GPIO pins)
and upon getting an interrupt read a message from the I2C target device.
The macro does a lot of the heavy lifting to setup all the state needed
for capturing GPIOs, being able to do asynchronous reads/writes, and
such. The entire controller works using state machines driven by
interrupts leading to low latency and clear ram costs.
Signed-off-by: Tom Burdick <thomas.burdick@intel.com>
Unfortunately libc malloc/free are wrapped with a sys_mutex which is
troublesome for mctp as we likely want to allocate from interrupts in many
cases.
Supply mctp with a dedicated heap initialized and assigned at boot
saving applications a step. The default size is quite small and works
well so long as messages are small.
Signed-off-by: Tom Burdick <thomas.burdick@intel.com>
The commit 1e0af58b51 ("pmci: Move MCTP into the PMCI subsys") changes
'mctp' directory adding to unconditionally, which will cause:
CMake Warning at ./zephyrproject/zephyr/CMakeLists.txt:1022 (message):
No SOURCES given to Zephyr library: subsys__pmci__mctp
Excluding target from build.
Signed-off-by: Haiyue Wang <haiyuewa@163.com>
PMCI conveys a stack of specifications from DMTF including MCTP (a
transport layer protocol), PLDM (request/response messaging protocol),
and ancillary SPDM messaging. Placing all these libraries under PMCI
subsystem makes more sense than simply adding MCTP as its own subsystem.
Signed-off-by: Tom Burdick <thomas.burdick@intel.com>
