The watchdog timeout is signaled using an interrupt and, on this
interrupt, a software initiated reset is performed.
This software initiated reset performs, in the end, a hardware system
reset using SWRST_REQ of RSTCTRL register.
The watchdog itself is able to control directly the hardware system
reset without any operation done by the interrupt handler. This feature
allows the watchdog to not depend on the software to reset the system
when a watchdog timeout occurs.
Indeed, when the watchdog timeout occurs, the watchdog requests a system
reset using its own hardware dedicated line but this reset source is
disabled at the reset controller level.
To benefit of this feature and be robust against software issues, enable
watchdogs reset sources.
Suggested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Herve Codina (Schneider Electric) <herve.codina@bootlin.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260324120435.243641-2-herve.codina@bootlin.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
/* Clear potentially pending resets */
writel(R9A06G032_SYSCTRL_WDA7RST_0 | R9A06G032_SYSCTRL_WDA7RST_1,
clocks->reg + R9A06G032_SYSCTRL_RSTCTRL);
- /* Allow software reset */
- writel(R9A06G032_SYSCTRL_SWRST | R9A06G032_SYSCTRL_RSTEN_MRESET_EN,
+ /* Allow watchdog and software resets */
+ writel(R9A06G032_SYSCTRL_WDA7RST_0 | R9A06G032_SYSCTRL_WDA7RST_1 |
+ R9A06G032_SYSCTRL_SWRST | R9A06G032_SYSCTRL_RSTEN_MRESET_EN,
clocks->reg + R9A06G032_SYSCTRL_RSTEN);
error = devm_register_sys_off_handler(dev, SYS_OFF_MODE_RESTART, SYS_OFF_PRIO_HIGH,