On Thu, Sep 04, 2025 at 02:48:03PM +0530, Pavan Kondeti wrote: > On Thu, Sep 04, 2025 at 09:13:23AM +0200, Neil Armstrong wrote: > > 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 ? > > > > This driver should work on 8550 and 8650 too as long as the hypervisor > overlay is applied to the device tree which happens in the bootloader. > You have easy access to 8550 and 8650 MTP/QRD devices, please give us a definitive answer. Regards, Bjorn > I remember porting some hypercalls to 8550 upstream kernel to induce the > watchdog bite in panic to collect the dumps. one of the biggest benefit > w/ this driver is that we can collect dumps upon kernel panic. since we > won't be able to pet the watchdog upon panic, the bite would eventually > happens and device enters dump collection mode. > > Thanks, > Pavan
