[PATCH RESEND 1/8] arm: dts: berlin2q: add watchdog nodes
Jisheng Zhang
jszhang at marvell.com
Sun Nov 22 20:59:53 PST 2015
On Fri, 20 Nov 2015 21:19:46 +0100
Sebastian Hesselbarth wrote:
> On 20.11.2015 04:34, Jisheng Zhang wrote:
> > On Thu, 19 Nov 2015 21:47:05 +0100
> > Sebastian Hesselbarth wrote:
> >> On 16.11.2015 12:09, Jisheng Zhang wrote:
> >>> The Marvell Berlin BG2Q has 3 watchdogs which are compatible with the
> >>> snps,dw-wdt driver sit in the sysmgr domain. This patch adds the
> >>> corresponding device tree nodes.
> >>>
> >>> Signed-off-by: Jisheng Zhang <jszhang at marvell.com>
> >>> ---
> >>> arch/arm/boot/dts/berlin2q.dtsi | 24 ++++++++++++++++++++++++
> >>> 1 file changed, 24 insertions(+)
> >>>
> >>> diff --git a/arch/arm/boot/dts/berlin2q.dtsi b/arch/arm/boot/dts/berlin2q.dtsi
> >>> index a3ecde5..fac4315 100644
> >>> --- a/arch/arm/boot/dts/berlin2q.dtsi
> >>> +++ b/arch/arm/boot/dts/berlin2q.dtsi
> >>> @@ -483,6 +483,30 @@
> >>> ranges = <0 0xfc0000 0x10000>;
> >>> interrupt-parent = <&sic>;
> >>>
> >>> + wdt0: watchdog at 1000 {
> >>> + compatible = "snps,dw-wdt";
> >>> + reg = <0x1000 0x100>;
> >>> + clocks = <&refclk>;
> >>> + interrupts = <0>;
> >>> + status = "disabled";
> >>
> >> as the watchdogs are internal and cannot be clock gated
> >> at all, how about we remove the status = "disabled" and
> >> make them always available?
> >
> > there are two issues here:
> >
> > 1. the dw-wdt can't support multiple variants now. I have rewrite the driver
> > with watchdog core supplied framework, but the patch isn't sent out and
> > may be need time to clean up and review.
>
> Ok.
>
> > 2. not all dw-wdt devices are available and functional. This depends on
> > board design and configuration.
>
> I understand that "board design and configuration" may hinder the wdt
> to issue a hard reset. But all others are able to issue a soft reset
> or just an interrupt, right?
>
> So, I still don't see why we should disable wdt nodes by default
> except for the driver issue above.
>
> > So IMHO status=disabled and patch5-8 is necessary, what do you think?
>
> No. I'd agree to enable wdt0 by default and leave wdt[1,2] disabled
> because of the driver issue. Patches 5-8 only enable wdt0 anyway.
That's fine.
>
> As soon as the driver issue is resolved, we enable all wdt nodes
> unconditionally.
I will submit patch for the wdt driver and hope it will be merged
in v4.5.
Thanks,
Jisheng
>
> Sebastian
>
> >> I have applied patches 1-4 with the status property removed.
> >> This also renders patches 5-8 useless.
> >>
> >> So, for now tentatively
> >>
> >> Appled to berlin/dt and berlin64/dt respectivly
> >>
> >> with status property removed.
> >>
> >> Sebastian
> >>
> >
>
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