On Thu, Jul 28, 2022 at 7:21 PM AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx> wrote: > > Il 27/07/22 11:40, Pin-yen Lin ha scritto: > > Switch to SMC watchdog because we need direct control of HW watchdog > > registers from kernel. The corresponding firmware was uploaded in > > https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/3405. > > > > Signed-off-by: Pin-yen Lin <treapking@xxxxxxxxxxxx> > > --- > > > > Changes in v2: > > - Move the modifications to mt8173-elm.dtsi and add some comments. > > > > arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi | 12 ++++++++++++ > > 1 file changed, 12 insertions(+) > > > > diff --git a/arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi b/arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi > > index e21feb85d822..b2269770abc3 100644 > > --- a/arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi > > +++ b/arch/arm64/boot/dts/mediatek/mt8173-elm.dtsi > > @@ -161,6 +161,18 @@ hdmi_connector_in: endpoint { > > }; > > }; > > }; > > + > > + soc { > > + /* > > + * Disable the original MMIO watch dog and switch to the SMC watchdog, > > + * which operates on the same MMIO. > > + */ > > + /delete-node/ watchdog@10007000; > > Unfortunately, we're not quite there yet. > The comment is fine, but... > > There's no need to /delete-node/: you can just do it like > > /* > * Disable the original MMIO watch dog and switch to the SMC watchdog, > * which operates on the same MMIO. > */ > &watchdog { > status = "disabled"; > }; > > and... > > > + > > + watchdog { > > This isn't addressable, hence it belongs to the root node, not to soc. > If you did that because of naming issues, I would propose to call it > smc-watchdog instead of watchdog. > > > > + compatible = "arm,smc-wdt"; > Thanks for the suggestion. I'll modify it accordingly in v3. > P.S.: No timeout-sec? The example in the binding file has a timeout-sec property, but it is not defined in the binding nor used in the driver... The driver seems to talk with the firmware to get a timeout value[1] instead of reading it from the devicetree. [1]: https://elixir.bootlin.com/linux/latest/source/drivers/watchdog/arm_smc_wdt.c#L138 > > Regards, > Angelo > > > + }; > > + }; > > }; > > > > &mfg_async { > > >
