firmware: ti_sci: Add support for querying the firmware caps

firmware: ti_sci: Add support for querying the firmware caps

Add support for the TISCI_MSG_QUERY_FW_CAPS message, used to retrieve
the firmware capabilities of the currently running system firmware. The
message belongs to the TISCI general core message API [1] and is
available in SysFW version 08.04.03 and above. Currently, the message is
supported on devices with split architecture of the system firmware (DM
+ TIFS) like AM62x. Old revisions or not yet supported platforms will
NACK this request.

We're using this message locally in ti_sci.c to get the low power
features of the FW/SoC. As there's no other kernel consumers yet, this
is not added to struct ti_sci_core_ops.

Sysfw version >= 10.00.04 support LPM_DM_MANAGED capability [2], where
Device Mgr firmware now manages which low power mode is chosen. Going
forward, this is the default configuration supported for TI AM62 family
of devices. The state chosen by the DM can be influenced by sending
constraints using the new LPM constraint APIs.

[1] https://software-dl.ti.com/tisci/esd/latest/2_tisci_msgs/general/core.html
[2] https://software-dl.ti.com/tisci/esd/latest/2_tisci_msgs/general/core.html#tisci-msg-query-fw-caps

Signed-off-by: Georgi Vlaev <g-vlaev@ti.com>
[vibhore@ti.com: Support for LPM_DM_MANAGED mode]
Signed-off-by: Vibhore Vardhan <vibhore@ti.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Tested-by: Dhruva Gole <d-gole@ti.com>
Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com>
Tested-by: Kevin Hilman <khilman@baylibre.com>
Tested-by: Roger Quadros <rogerq@kernel.org>
Acked-by: Dhruva Gole <d-gole@ti.com>
Link: https://lore.kernel.org/r/20241007-tisci-syssuspendresume-v13-2-ed54cd659a49@baylibre.com
Signed-off-by: Nishanth Menon <nm@ti.com>