Re: [PATCH v2] cdx: add MSI support for CDX bus

From: Nipun Gupta
Date: Tue Jun 06 2023 - 07:05:35 EST




On 5/18/2023 5:14 PM, Nipun Gupta wrote:
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@xxxxxxx>
Signed-off-by: Nikhil Agarwal <nikhil.agarwal@xxxxxxx>
Co-developed-by: Abhijit Gangurde <abhijit.gangurde@xxxxxxx>
Signed-off-by: Abhijit Gangurde <abhijit.gangurde@xxxxxxx>
Signed-off-by: Nipun Gupta <nipun.gupta@xxxxxxx>
Reviewed-by: Pieter Jansen van Vuuren <pieter.jansen-van-vuuren@xxxxxxx>
Tested-by: Nikhil Agarwal <nikhil.agarwal@xxxxxxx>
---

Changes v1->v2:
- fixed scenario where msi write was called asyncronously in
an atomic context, by using irq_chip_(un)lock, and using sync
MCDI API for write MSI message.
- fixed broken Signed-off-by chain.

Hi Thomas,

Did you had a chance to look at patch v2. Please let me know in case anything else is required to be updated.

Thanks,
Nipun