Re: [PATCH 1/2] dt-bindings: watchdog: Add arm,smc-wdt watchdog arm,smc-wdt compatible

From: Julius Werner
Date: Mon Feb 24 2020 - 20:24:01 EST


> The SMC function ID may be solved by the DTS, but the wdt indexs(Eg:
> SMCWD_INFO) are also different
> for each vendor. The imx_sc_wdt.c is also use the SMC to operate the
> WDT, but the wdt indexs(Eg: IMX_SIP_TIMER_START_WDOG)
> are different from ours. IMO, If the ATF can implement a common hal
> interface and index for watchdog, then writing a
> common smc wdt driver will be easier to compatible with all vendors.

The MediaTek driver is still in flux (e.g. still being reviewed in
Trusted Firmware here:
https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/3405),
we can still change it. So if we can now decide on making this a
"standard" driver, we can change the MediaTek interface to match IMX
and standardize on that. (There are existing Chromebooks shipped with
a different interface, but we could handle those separately with
downstream patches. I think having a unified interface that will
prevent this problem in the future would be worth some extra
complication right now.)