[PATCH 0/2] remoteproc: k3: Recover a crashed remote core

[Chrispine Tinega <dev@chrispinetinega.com>]

A K3 remote core can tell Linux it has crashed by sending RP_MBOX_CRASH,
but the K3 drivers only log it. Nothing reaches the remoteproc core, so
the crash is not counted and recovery never runs. The core stays halted
until the next boot, with its rpmsg channels dead.

Patch 1 reports the crash with rproc_report_crash(). This applies to
every K3 remote that uses the common mailbox callback.

Patch 2 leaves recovery enabled on the M4F. Its stop is a plain reset,
so recovery does not need the crashed core to answer. The R5F and DSP
drivers keep recovery disabled. A crashed core there moves to
RPROC_CRASHED, and can be stopped and started again through sysfs.

Tested on an AM625 board (BLIIoT BL350) running TI's 6.12 kernel with
the equivalent change. The M4F runs Zephyr, whose fatal-error handler
sends RP_MBOX_CRASH. After a forced fault, recovery reset and rebooted
the M4F in 71 ms, and Linux kept running. Mainline's M4F stop is the
same plain reset that this test used for a crashed core.

Chrispine Tinega (2):
  remoteproc: k3: Report a remote crash to the remoteproc core
  remoteproc: k3-m4: Leave crash recovery enabled

 drivers/remoteproc/ti_k3_common.c        | 5 +----
 drivers/remoteproc/ti_k3_m4_remoteproc.c | 1 -
 2 files changed, 1 insertion(+), 5 deletions(-)


base-commit: ec1f9ba57b02fe12a6fa5f141206d439ba3d044e
-- 
2.53.0