On 12.07.23 08:05, Li, Hua Qian (DI FA CTR IPC CN PRC4) wrote: > On Tue, 2023-07-11 at 22:01 -0700, Guenter Roeck wrote: >> On a higher level, the entire code puzzles me. Obviously there >> must be a means for the BIOS or ROMMON to write PON_REASON_SOF_NUM >> into some memory area. That means the BIOS/ROMMON must be able >> to detect that situation. Why not use the same code to detect this >> in the driver without the complexity of passing it from BIOS/ROMMON >> to driver in some random memory area ? >> > In TI AM65x cases, the hardware is not capable of issuing a reset on > its own, and is not possible to record or detect the watchdog reset > situation. So `k3-rit-wdt` firmware which runs in a mcu core was used > to detect the watchdog interrupt and reset the Soc. Here I am trying to > write the reason in this firmware when watchdog interrupt happens, and > read it out in kernel. See https://github.com/siemens/k3-rti-wdt/issues/1 for where this started and where the firmware part comes into play. I still wonder why we couldn't have had a nicer hardware watchdog instead but this can't be changed anymore. Jan -- Siemens AG, Technology Competence Center Embedded Linux
