The Marvell switches have an in built watchdog over some of the internal state machine. The watchdog can be configured to raise an interrupt on error. The problem the watchdog found is then logged to the kernel log.
The older switches can automagically perform a software reset when the watchdog triggers. This just resets the internal state machine, but leaves the switch configuration unchanged. The 6390 family of switches cannot both raise an interrupt and automagically perform a software reset. So the interrupt handler has to perform the switch reset, and then re-enable the watchdog interrupts. This has been tested using hacked together debugfs code which allows the "force" bit to be set, so cause a watchdog interrupt. v2: Remove g2_prefix Andrew Lunn (2): net: dsa: mv88e6xxx: Add watchdog interrupt handler net: dsa: mv88e6xxx: Add mv88e6390 watchdog interrupt support drivers/net/dsa/mv88e6xxx/chip.c | 23 ++++++ drivers/net/dsa/mv88e6xxx/global2.c | 137 +++++++++++++++++++++++++++++++++- drivers/net/dsa/mv88e6xxx/global2.h | 6 ++ drivers/net/dsa/mv88e6xxx/mv88e6xxx.h | 33 ++++++++ 4 files changed, 198 insertions(+), 1 deletion(-) -- 2.11.0
