Re: [PATCH v2 3/4] ARM: dts: armada-38x: Fix compatible string for gpios

[Pali Rohár <pali@xxxxxxxxxx>]

On Monday 25 July 2022 22:04:17 Uwe Kleine-König wrote:
> Hello Pali,
> 
> On Sat, Jul 16, 2022 at 06:09:16PM +0200, Pali Rohár wrote:
> > On Saturday 16 July 2022 17:07:51 Uwe Kleine-König wrote:
> > > On Sat, Jul 16, 2022 at 04:50:19PM +0200, Pali Rohár wrote:
> > > > On Saturday 16 July 2022 16:40:28 Uwe Kleine-König wrote:
> > > > > On Thu, Jul 14, 2022 at 08:33:27PM +0200, Pali Rohár wrote:
> > > > > > Armada 38x supports per CPU interrupts for gpios, like Armada XP. Pre-XP
> > > > > > variants like Armada 370 do not support per CPU interrupts for gpios.
> > > > > > 
> > > > > > So change compatible string for Armada 38x from "marvell,armada-370-gpio"
> > > > > > which indicates pre-XP variant to "marvell,armadaxp-gpio" which indicates
> > > > > > XP variant or new.
> > > > > > 
> > > > > > Driver gpio-mvebu.c which handles both pre-XP and XP variants already
> > > > > > provides support for per CPU interrupts on XP and newer variants.
> > > > > > 
> > > > > > Signed-off-by: Pali Rohár <pali@xxxxxxxxxx>
> > > > > > Fixes: 7cb2acb3fbae ("ARM: dts: mvebu: Add PWM properties for armada-38x")
> > > > > > ---
> > > > > >  arch/arm/boot/dts/armada-38x.dtsi | 4 ++--
> > > > > >  1 file changed, 2 insertions(+), 2 deletions(-)
> > > > > > 
> > > > > > diff --git a/arch/arm/boot/dts/armada-38x.dtsi b/arch/arm/boot/dts/armada-38x.dtsi
> > > > > > index df3c8d1d8f64..9343de6947b3 100644
> > > > > > --- a/arch/arm/boot/dts/armada-38x.dtsi
> > > > > > +++ b/arch/arm/boot/dts/armada-38x.dtsi
> > > > > > @@ -292,7 +292,7 @@
> > > > > >  			};
> > > > > >  
> > > > > >  			gpio0: gpio@18100 {
> > > > > > -				compatible = "marvell,armada-370-gpio",
> > > > > > +				compatible = "marvell,armadaxp-gpio",
> > > > > >  					     "marvell,orion-gpio";
> > > > > 
> > > > > If you can treat the XP variant as 370 and everything that is supposed
> > > > > to work on 370 works then, then maybe the right incarnation is:
> > > > > 
> > > > > 	compatible = "marvell,armadaxp-gpio", "marvell,armada-370-gpio", "marvell,orion-gpio";
> > > > > 
> > > > > ?
> > > > 
> > > > For pre-XP variants is "marvell,orion-gpio" enough and for XP + post-XP
> > > > is needed "marvell,armadaxp-gpio" (with possible "marvell,orion-gpio"
> > > > for backward compatibility).
> > > > 
> > > > So I do not see reason why to add "marvell,armada-370-gpio" nor what
> > > > value it brings.
> > > 
> > > If you boot an older kernel (i.e. one that doesn't support
> > > marvell,armadaxp-gpio, but does support marvell,armada-370-gpio), it
> > 
> > Is there such kernel version?
> 
> Ah, I thought you added "marvell,armadaxp-gpio" with this patch series.
> 
> > > will work better as there are relevant differences between
> > > marvell,orion-gpio and marvell,armada-370-gpio.
> > 
> > And if yes, do we really need this in DTS files for new kernel
> > versions? I can imagine that such change can be relevant for old LTS
> > kernel version, but not for new versions.
> > 
> > > For example some
> > > registers seem to have a different offset ...
> > 
> > armada-370-gpio is mapped to MVEBU_GPIO_SOC_VARIANT_ORION, so it will
> > get same offsets as orion-gpio. So no change.
> 
> OK, you're right, my assumptions were wrong. I'm convinced your change
> is fine now:
> 
> Acked-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
> 
> Best regards
> Uwe

Ok, are there any other objections with this patch series?