On 03/09/2025 21:33, Hrishabh Rajput via B4 Relay wrote:

Gunyah is a Type-I hypervisor which was introduced in the patch series
[1]. It is an open source hypervisor. The source repo is available at
[2].

The Gunyah Hypervisor doesn't allow its Virtual Machines to directly
access the MMIO watchdog. It either provides the fully emulated MMIO
based watchdog interface or the SMC-based watchdog interface depending
on the hypervisor configuration.
The SMC-based watchdog follows ARM's SMC Calling Convention (SMCCC)
version 1.1 and uses Vendor Specific Hypervisor Service Calls space.

This patch series adds support for the SMC-based watchdog interface
provided by the Gunyah Hypervisor. The driver supports start/stop
operations, timeout and pretimeout configuration, pretimeout interrupt
handling and system restart via watchdog.

This series is tested on SM8750 platform.

Would this driver work on older platforms like SM8550 & SM8650 ?

Thanks,
Neil

[1]
https://lore.kernel.org/all/20240222-gunyah-v17-0-1e9da6763d38@quicinc.com/ (local)

[2]
https://github.com/quic/gunyah-hypervisor

Signed-off-by: Hrishabh Rajput <redacted>
---
Hrishabh Rajput (2):
       dt-bindings: Add binding for gunyah watchdog
       watchdog: Add driver for Gunyah Watchdog

  .../bindings/watchdog/qcom,gh-watchdog.yaml        |  76 ++++++
  MAINTAINERS                                        |   3 +
  drivers/watchdog/Kconfig                           |  13 +
  drivers/watchdog/Makefile                          |   1 +
  drivers/watchdog/gunyah_wdt.c                      | 268 +++++++++++++++++++++
  include/linux/gunyah_errno.h                       |  77 ++++++
  6 files changed, 438 insertions(+)
---
base-commit: 038d61fd642278bab63ee8ef722c50d10ab01e8f
change-id: 20250903-gunyah_watchdog-2d2649438e29

Best regards,