Merge tag 'scmi-updates-6.12' of https://git.kernel.org/pub/scm/linux/kernel/git...

Merge tag 'scmi-updates-6.12' of https://git./linux/kernel/git/sudeep.holla/linux into soc/drivers

Arm SCMI updates for v6.12

Few main features include:

1. SCMI transport as stand-alone drivers

    Currently the SCMI transport layer is being built embedded into in
    the core SCMI stack. Some of these transports, despite being currently
    part of the main SCMI module, are indeed also registered with different
    subsystems like optee or virtio, and actively probed also by those.
    This leads to a few awkward and convoluted tricks to properly handle
    such interactions at boot time in the SCMI stack.

    This change adds the new logic to the core SCMI stack so that each
    existing transport is transitioned to be a standi-alone driver. With
    that all the probe deferral and awkward retries between the SCMI
    core stack and the transports has been removed, since no more needed.

2. Support for obtaining transport descriptors from the devicetree

    SCMI platform firmwares might have different designs depending on
    the platform. Some of the transport descriptors rely on such design.
    E.g. the maximum receive channel timeout value might vary depending
    on the specific underlying hardware and firmware design choices.

    This change adds support for max-rx-timeout-ms property to describe
    the transport needs of a specific platform design. It will be extended
    in the future to obtain other such hardware/firmware dependent
    transport related descriptors.

3. NXP i.MX95 specific SCMI vendor protocol extensions

    SCMI specification allows vendor or platform-specific extensions to
    the interface. NXP i.MX95 System Manager(SM) that implements SCMI
    extends the interface to implement couple of vendor/platform specific
    protocol, namely:
    a. Battery Backed Module(BBM) Protocol

       This protocol is intended provide access to the battery-backed
       module. This contains persistent storage (GPR), an RTC, and the
       ON/OFF button. The protocol can also provide access to similar
       functions implemented via external board components.

    b. MISC Protocol for misc settings

        This includes controls that are misc settings/actions that must
	be exposed from the SM to agents. They are device specific and
	are usually define to access bit fields in various mix block
	control modules, IOMUX_GPR, and other GPR/CSR owned by the SM.

4. SCMI debug/tracking metrics

    Since SCMI involves interaction with the entity(software, firmware
    and/or hardware) providing services or features, it is quite useful
    to track certain metrics(for pure debugging purposes) like how many
    messages were sent or received, were there any failures, what kind
    of failures, ..etc. This feature adds support for the same via debugfs.

Apart from these main features, there are some miscellaneous updates, fixes
and cleanups.

* tag 'scmi-updates-6.12' of https://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux: (31 commits)
  rtc: support i.MX95 BBM RTC
  input: keyboard: support i.MX95 BBM module
  firmware: imx: Add i.MX95 MISC driver
  firmware: arm_scmi: Add initial support for i.MX MISC protocol
  firmware: arm_scmi: Add initial support for i.MX BBM protocol
  firmware: arm_scmi: Add NXP i.MX95 SCMI documentation
  dt-bindings: firmware: Add i.MX95 SCMI Extension protocol
  firmware: arm_scmi: Replace comma with the semicolon
  firmware: arm_scmi: Replace the use of of_node_put() to __free(device_node)
  firmware: arm_scmi: Fix trivial whitespace/coding style issues
  firmware: arm_scmi: Use max-rx-timeout-ms from devicetree
  dt-bindings: firmware: arm,scmi: Introduce property max-rx-timeout-ms
  firmware: arm_scmi: Remove const from transport descriptors
  firmware: arm_scmi: Simplify with scoped for each OF child loop
  firmware: arm_scmi: Update various protocols versions
  firmware: arm_scmi: Remove legacy transport-layer code
  firmware: arm_scmi: Make VirtIO transport a standalone driver
  firmware: arm_scmi: Make OPTEE transport a standalone driver
  firmware: arm_scmi: Make SMC transport a standalone driver
  firmware: arm_scmi: Make MBOX transport a standalone driver
  ...

Link: https://lore.kernel.org/r/20240830135918.2383664-1-sudeep.holla@arm.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>