cdx: add MSI support for CDX bus

Add CDX-MSI domain per CDX controller with gic-its domain as
a parent, to support MSI for CDX devices. CDX devices allocate
MSIs from the CDX domain. Also, introduce APIs to alloc and free
IRQs for CDX domain.

In CDX subsystem firmware is a controller for all devices and
their configuration. CDX bus controller sends all the write_msi_msg
commands to firmware running on RPU and the firmware interfaces with
actual devices to pass this information to devices

Since, CDX controller is the only way to communicate with the Firmware
for MSI write info, CDX domain per controller required in contrast to
having a CDX domain per device.

Co-developed-by: Nikhil Agarwal <nikhil.agarwal@amd.com>
Signed-off-by: Nikhil Agarwal <nikhil.agarwal@amd.com>
Co-developed-by: Abhijit Gangurde <abhijit.gangurde@amd.com>
Signed-off-by: Abhijit Gangurde <abhijit.gangurde@amd.com>
Signed-off-by: Nipun Gupta <nipun.gupta@amd.com>
Reviewed-by: Pieter Jansen van Vuuren <pieter.jansen-van-vuuren@amd.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Nikhil Agarwal <nikhil.agarwal@amd.com>
Link: https://lore.kernel.org/r/20240226082816.100872-1-nipun.gupta@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

cdx: add support for bus enable and disable

CDX bus needs to be disabled before updating/writing devices
in the FPGA. Once the devices are written, the bus shall be
rescanned. This change provides sysfs entry to enable/disable the
CDX bus.

Co-developed-by: Nipun Gupta <nipun.gupta@amd.com>
Signed-off-by: Nipun Gupta <nipun.gupta@amd.com>
Signed-off-by: Abhijit Gangurde <abhijit.gangurde@amd.com>
Link: https://lore.kernel.org/r/20231017160505.10640-6-abhijit.gangurde@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

cdx: add support for bus mastering

Introduce cdx_set_master() and cdx_clear_master() APIs to support
enable and disable of bus mastering. Drivers need to use these APIs to
enable/disable DMAs from the CDX devices.

Signed-off-by: Nipun Gupta <nipun.gupta@amd.com>
Reviewed-by: Pieter Jansen van Vuuren <pieter.jansen-van-vuuren@amd.com>
Link: https://lore.kernel.org/r/20230915045423.31630-1-nipun.gupta@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

cdx: add device attributes

Create sysfs entry for CDX devices.

Sysfs entries provided in each of the CDX device detected by
the CDX controller
- vendor id
- device id
- remove
- reset of the device.
- driver override

Signed-off-by: Puneet Gupta <puneet.gupta@amd.com>
Signed-off-by: Nipun Gupta <nipun.gupta@amd.com>
Signed-off-by: Tarak Reddy <tarak.reddy@amd.com>
Reviewed-by: Pieter Jansen van Vuuren <pieter.jansen-van-vuuren@amd.com>
Tested-by: Nikhil Agarwal <nikhil.agarwal@amd.com>
Link: https://lore.kernel.org/r/20230313132636.31850-8-nipun.gupta@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

cdx: add cdx controller

CDX controller uses MCDI interface as a protocol to
communicate with the RPU firmware and registers the
detected CDX devices on the CDX bus. It also uses
RPMsg as the communication channel with the Firmware.

Signed-off-by: Nipun Gupta <nipun.gupta@amd.com>
Signed-off-by: Puneet Gupta <puneet.gupta@amd.com>
Signed-off-by: Abhijit Gangurde <abhijit.gangurde@amd.com>
Signed-off-by: Nikhil Agarwal <nikhil.agarwal@amd.com>
Reviewed-by: Pieter Jansen van Vuuren <pieter.jansen-van-vuuren@amd.com>
Tested-by: Nikhil Agarwal <nikhil.agarwal@amd.com>
Link: https://lore.kernel.org/r/20230313132636.31850-6-nipun.gupta@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>