[v2,0/2] Support for I/O width within ARM SCMI SHMEM

Message

Florian Fainelli Aug. 13, 2024, 6:07 p.m. UTC

We just got our hands on hardware that only supports 32-bit access width
to the SRAM being used. This patch series adds support for the
'reg-io-width' property and allows us to specify the exact access width
that the SRAM supports.

Changes in v2:

- fixed typo in the binding and added reviewed-by tag from Krzysztof

- determine the correct I/O operation at the time we parse the
  'reg-io-width' property rather than for each
  tx_prepare/fetch_response/fetch_notification call

- dropped support for 1 and 2 bytes 'reg-io-width' as they do not quite
  make sense, if we can support such smaller access size, then we can
  support the larger 4 byte access width, too, and there are many places
  within the SCMI code where ioread32/iowrite32 are used

Florian Fainelli (2):
  dt-bindings: sram: Document reg-io-width property
  firmware: arm_scmi: Support 'reg-io-width' property for shared memory

 .../devicetree/bindings/sram/sram.yaml        |  6 ++
 drivers/firmware/arm_scmi/common.h            | 32 +++++++-
 .../arm_scmi/scmi_transport_mailbox.c         | 13 ++-
 .../firmware/arm_scmi/scmi_transport_optee.c  | 10 ++-
 .../firmware/arm_scmi/scmi_transport_smc.c    | 11 ++-
 drivers/firmware/arm_scmi/shmem.c             | 81 +++++++++++++++++--
 6 files changed, 132 insertions(+), 21 deletions(-)