Re: [PATCH 1/2] dt-bindings: watchdog: mediatek,mtk-wdt: add MT7988 watchdog and toprgu

[Daniel Golle <daniel@makrotopia.org>]

On Fri, Nov 10, 2023 at 03:46:14PM +0100, Krzysztof Kozlowski wrote:
> On 10/11/2023 15:40, Daniel Golle wrote:
> > On Fri, Nov 10, 2023 at 03:20:53PM +0100, Krzysztof Kozlowski wrote:
> >> On 10/11/2023 15:17, Daniel Golle wrote:
> >>> On Fri, Nov 10, 2023 at 12:56:18PM +0100, AngeloGioacchino Del Regno wrote:
> >>>> Il 10/11/23 01:30, Daniel Golle ha scritto:
> >>>>> Add binding description for mediatek,mt7988-wdt.
> >>>>>
> >>>>> Signed-off-by: Daniel Golle <daniel@makrotopia.org>
> >>>>> ---
> >>>>>   .../bindings/watchdog/mediatek,mtk-wdt.yaml          |  1 +
> >>>>>   include/dt-bindings/reset/mediatek,mt7988-resets.h   | 12 ++++++++++++
> >>>>>   2 files changed, 13 insertions(+)
> >>>>>   create mode 100644 include/dt-bindings/reset/mediatek,mt7988-resets.h
> >>>>>
> >>>>> diff --git a/Documentation/devicetree/bindings/watchdog/mediatek,mtk-wdt.yaml b/Documentation/devicetree/bindings/watchdog/mediatek,mtk-wdt.yaml
> >>>>> index cc502838bc398..8d2520241e37f 100644
> >>>>> --- a/Documentation/devicetree/bindings/watchdog/mediatek,mtk-wdt.yaml
> >>>>> +++ b/Documentation/devicetree/bindings/watchdog/mediatek,mtk-wdt.yaml
> >>>>> @@ -25,6 +25,7 @@ properties:
> >>>>>             - mediatek,mt6735-wdt
> >>>>>             - mediatek,mt6795-wdt
> >>>>>             - mediatek,mt7986-wdt
> >>>>> +          - mediatek,mt7988-wdt
> >>>>>             - mediatek,mt8183-wdt
> >>>>>             - mediatek,mt8186-wdt
> >>>>>             - mediatek,mt8188-wdt
> >>>>> diff --git a/include/dt-bindings/reset/mediatek,mt7988-resets.h b/include/dt-bindings/reset/mediatek,mt7988-resets.h
> >>>>> new file mode 100644
> >>>>> index 0000000000000..fa7c937505e08
> >>>>> --- /dev/null
> >>>>> +++ b/include/dt-bindings/reset/mediatek,mt7988-resets.h
> >>>>> @@ -0,0 +1,12 @@
> >>>>> +/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
> >>>>> +
> >>>>> +/* TOPRGU resets */
> >>>>
> >>>> The first reset is zero, the second reset is one.
> >>>>
> >>>> Where's the zero'th reset? :-)
> >>>
> >>> Currently the reset numbers represent the corresponding bit positions in
> >>> the toprgu register, as this is how the mtk-wdt driver is organized.
> >>>
> >>> So there is probably something at bit 0, and also at bit 3~11 and
> >>> maybe also 17~23, but it's unknown and may be added later once known
> >>> and/or needed.
> >>
> >> There is no need to put register bits, which are not used by the driver,
> >> in the bindings.
> > 
> > There aren't. That's why there isn't a zero'th reset (and also not 3~11, 17~24).
> > 
> > Or should the driver be reorganized to provide a mapping of logical to
> > physical resets, and then have only the needed once present and start
> > counting logical resets from 0? This is doable, of course, but it's a
> > bit of effort just for the aesthetical goal of starting to count from
> > zero and continous in header file.
> > 
> > And, of course, chances are that other currently still unused bits
> > will be needed at a later point which then would mean having to add
> > them in at least 2 places (header file and mapping logical<->physical)
> > where as currently it would just mean adding a line defining it in the
> > header file.
> 
> You can do it, but it's not what I wrote here. So bear with me:
> 
> "There is no need to put register bits in the bindings."
> 
> You replied "There aren't", which I don't understand in this context. I
> can be clearer:
> Drop this hunk.

So adding the file to include/dt-bindings/reset/ should go into a
seperate patch? Because including it with the driver itself gave me
a checkpath warning telling me that dt-bindings should go seperate,
which is why I included it with the binding docs.

> 
> > 
> > A quick looks at all the other headers in
> > include/dt-binding/reset/mt*-resets.h also shows that currently all of
> > them have unused bits and e.g. infracfg on MT7986 starts counting from
> > 6.
> 
> Best regards,
> Krzysztof
> 
>