| Message ID | 1545148524-658-2-git-send-email-aisheng.dong@nxp.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
| Series | firmware: imx: scu-pd: add fallback compatible string support | expand |
On Tue, 18 Dec 2018 16:01:20 +0000, Aisheng Dong wrote: > SCU power domain can be used in the same way by IMX8QXP and IMX8QM SoCs. > Let's add a "fsl,scu-pd" fallback compatible string to allow other SoCs > to reuse the common part. > > Cc: Ulf Hansson <ulf.hansson@linaro.org> > Cc: Rob Herring <robh+dt@kernel.org> > Cc: Shawn Guo <shawnguo@kernel.org> > Cc: Sascha Hauer <kernel@pengutronix.de> > Cc: Fabio Estevam <fabio.estevam@nxp.com> > Cc: Mark Rutland <mark.rutland@arm.com> > Cc: devicetree@vger.kernel.org > Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com> > --- > Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > Reviewed-by: Rob Herring <robh@kernel.org>
On Tue, Dec 18, 2018 at 04:01:20PM +0000, Aisheng Dong wrote: > SCU power domain can be used in the same way by IMX8QXP and IMX8QM SoCs. > Let's add a "fsl,scu-pd" fallback compatible string to allow other SoCs > to reuse the common part. This is not the practice we used to match devices with compatibilities, i.e. coding the compatible string with the SoC name that firstly introduces the device, and use the compatible as fallback for new SoCs. Shawn > > Cc: Ulf Hansson <ulf.hansson@linaro.org> > Cc: Rob Herring <robh+dt@kernel.org> > Cc: Shawn Guo <shawnguo@kernel.org> > Cc: Sascha Hauer <kernel@pengutronix.de> > Cc: Fabio Estevam <fabio.estevam@nxp.com> > Cc: Mark Rutland <mark.rutland@arm.com> > Cc: devicetree@vger.kernel.org > Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com> > --- > Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt > index c20f38e..849b671 100644 > --- a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt > +++ b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt > @@ -58,7 +58,10 @@ This binding for the SCU power domain providers uses the generic power > domain binding[2]. > > Required properties: > -- compatible: Should be "fsl,imx8qxp-scu-pd". > +- compatible: Should be one of: > + "fsl,imx8qxp-scu-pd" > + followed by "fsl,scu-pd" > + > - #power-domain-cells: Must be 1. Contains the Resource ID used by > SCU commands. > See detailed Resource ID list from: > @@ -145,7 +148,7 @@ firmware { > }; > > pd: imx8qx-pd { > - compatible = "fsl,imx8qxp-scu-pd"; > + compatible = "fsl,imx8qxp-scu-pd", "fsl,scu-pd"; > #power-domain-cells = <1>; > }; > }; > -- > 2.7.4 >
On Fri, Jan 11, 2019 at 05:00:11PM +0800, Shawn Guo wrote: > On Tue, Dec 18, 2018 at 04:01:20PM +0000, Aisheng Dong wrote: > > SCU power domain can be used in the same way by IMX8QXP and IMX8QM SoCs. > > Let's add a "fsl,scu-pd" fallback compatible string to allow other SoCs > > to reuse the common part. > > This is not the practice we used to match devices with compatibilities, > i.e. coding the compatible string with the SoC name that firstly > introduces the device, and use the compatible as fallback for new SoCs. For example, in imx8qm device tree, we can use compatible below to get it work without change on kernel driver, while we still need to document the compatible "fsl,imx8qm-scu-pd". compatible = "fsl,imx8qm-scu-pd", "fsl,imx8qxp-scu-pd"; Shawn
Hi Shawn, > -----Original Message----- > From: Shawn Guo [mailto:shawnguo@kernel.org] > Sent: Friday, January 11, 2019 5:07 PM > > On Fri, Jan 11, 2019 at 05:00:11PM +0800, Shawn Guo wrote: > > On Tue, Dec 18, 2018 at 04:01:20PM +0000, Aisheng Dong wrote: > > > SCU power domain can be used in the same way by IMX8QXP and > IMX8QM SoCs. > > > Let's add a "fsl,scu-pd" fallback compatible string to allow other > > > SoCs to reuse the common part. > > > > This is not the practice we used to match devices with > > compatibilities, i.e. coding the compatible string with the SoC name > > that firstly introduces the device, and use the compatible as fallback for new > SoCs. > This is suggested by Rob that if the future SoCs are likely to be compatible. Then we can use a general fallback compatible string like "fsl,scu-pd". https://patchwork.kernel.org/patch/10644815/ From SCU HW protocol point of view, they're indeed compatible. Just varies a bit on the domains numbers. That's why we introduce "fsl,scu-pd". But still keep SoC specific compatible string in case any special tricks to ensure the ABI stability. How do you think? Regards Dong Aisheng > For example, in imx8qm device tree, we can use compatible below to get it > work without change on kernel driver, while we still need to document the > compatible "fsl,imx8qm-scu-pd". > > compatible = "fsl,imx8qm-scu-pd", "fsl,imx8qxp-scu-pd"; > > Shawn
On Fri, Jan 11, 2019 at 10:48:21AM +0000, Aisheng Dong wrote: > Hi Shawn, > > > -----Original Message----- > > From: Shawn Guo [mailto:shawnguo@kernel.org] > > Sent: Friday, January 11, 2019 5:07 PM > > > > On Fri, Jan 11, 2019 at 05:00:11PM +0800, Shawn Guo wrote: > > > On Tue, Dec 18, 2018 at 04:01:20PM +0000, Aisheng Dong wrote: > > > > SCU power domain can be used in the same way by IMX8QXP and > > IMX8QM SoCs. > > > > Let's add a "fsl,scu-pd" fallback compatible string to allow other > > > > SoCs to reuse the common part. > > > > > > This is not the practice we used to match devices with > > > compatibilities, i.e. coding the compatible string with the SoC name > > > that firstly introduces the device, and use the compatible as fallback for new > > SoCs. > > > > This is suggested by Rob that if the future SoCs are likely to be compatible. > Then we can use a general fallback compatible string like "fsl,scu-pd". > https://patchwork.kernel.org/patch/10644815/ > > From SCU HW protocol point of view, they're indeed compatible. > Just varies a bit on the domains numbers. > That's why we introduce "fsl,scu-pd". > But still keep SoC specific compatible string in case any special tricks > to ensure the ABI stability. > > How do you think? Unless Rob is against the practice we have been used for long time on i.MX, I would keep using it for i.MX8, i.e. instead of introducing a generic compatible for fallback, simply falling on the compatible SoC specified IP block. Shawn
> From: Shawn Guo [mailto:shawnguo@kernel.org] > Sent: Friday, January 11, 2019 9:03 PM > On Fri, Jan 11, 2019 at 10:48:21AM +0000, Aisheng Dong wrote: > > Hi Shawn, > > > > > -----Original Message----- > > > From: Shawn Guo [mailto:shawnguo@kernel.org] > > > Sent: Friday, January 11, 2019 5:07 PM > > > > > > On Fri, Jan 11, 2019 at 05:00:11PM +0800, Shawn Guo wrote: > > > > On Tue, Dec 18, 2018 at 04:01:20PM +0000, Aisheng Dong wrote: > > > > > SCU power domain can be used in the same way by IMX8QXP and > > > IMX8QM SoCs. > > > > > Let's add a "fsl,scu-pd" fallback compatible string to allow > > > > > other SoCs to reuse the common part. > > > > > > > > This is not the practice we used to match devices with > > > > compatibilities, i.e. coding the compatible string with the SoC > > > > name that firstly introduces the device, and use the compatible as > > > > fallback for new > > > SoCs. > > > > > > > This is suggested by Rob that if the future SoCs are likely to be compatible. > > Then we can use a general fallback compatible string like "fsl,scu-pd". > > > > > > From SCU HW protocol point of view, they're indeed compatible. > > Just varies a bit on the domains numbers. > > That's why we introduce "fsl,scu-pd". > > But still keep SoC specific compatible string in case any special > > tricks to ensure the ABI stability. > > > > How do you think? > > Unless Rob is against the practice we have been used for long time on i.MX, I > would keep using it for i.MX8, i.e. instead of introducing a generic compatible > for fallback, simply falling on the compatible SoC specified IP block. > Hmm, i feel protocol based devices is slightly a bit different from our old practice. See ARM and TI are all used generic compatible string. Documentation/devicetree/bindings/arm/arm,scpi.txt Documentation/devicetree/bindings/soc/ti/sci-pm-domain.txt If from firmware protocol point of view, they're defined SoC independent. SW(driver) implementation might be a different on platforms due to special tricks or implemented as platform independent. Anyway, if you strongly against this, i will change to what you requested. Regards Dong Aisheng > Shawn
On Fri, Jan 11, 2019 at 7:03 AM Shawn Guo <shawnguo@kernel.org> wrote: > > On Fri, Jan 11, 2019 at 10:48:21AM +0000, Aisheng Dong wrote: > > Hi Shawn, > > > > > -----Original Message----- > > > From: Shawn Guo [mailto:shawnguo@kernel.org] > > > Sent: Friday, January 11, 2019 5:07 PM > > > > > > On Fri, Jan 11, 2019 at 05:00:11PM +0800, Shawn Guo wrote: > > > > On Tue, Dec 18, 2018 at 04:01:20PM +0000, Aisheng Dong wrote: > > > > > SCU power domain can be used in the same way by IMX8QXP and > > > IMX8QM SoCs. > > > > > Let's add a "fsl,scu-pd" fallback compatible string to allow other > > > > > SoCs to reuse the common part. > > > > > > > > This is not the practice we used to match devices with > > > > compatibilities, i.e. coding the compatible string with the SoC name > > > > that firstly introduces the device, and use the compatible as fallback for new > > > SoCs. > > > > > > > This is suggested by Rob that if the future SoCs are likely to be compatible. > > Then we can use a general fallback compatible string like "fsl,scu-pd". > > https://patchwork.kernel.org/patch/10644815/ > > > > From SCU HW protocol point of view, they're indeed compatible. > > Just varies a bit on the domains numbers. > > That's why we introduce "fsl,scu-pd". > > But still keep SoC specific compatible string in case any special tricks > > to ensure the ABI stability. > > > > How do you think? > > Unless Rob is against the practice we have been used for long time on > i.MX, I would keep using it for i.MX8, i.e. instead of introducing a > generic compatible for fallback, simply falling on the compatible SoC > specified IP block. That is certainly my preference and the traditional way to do compatible in DT, but some reason folks don't like having old SoC names in their shiny new SoC DT. So either way is fine. But I'd follow what you do for the rest of i.MX which I guess is what Shawn suggests. Rob
diff --git a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt index c20f38e..849b671 100644 --- a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt +++ b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt @@ -58,7 +58,10 @@ This binding for the SCU power domain providers uses the generic power domain binding[2]. Required properties: -- compatible: Should be "fsl,imx8qxp-scu-pd". +- compatible: Should be one of: + "fsl,imx8qxp-scu-pd" + followed by "fsl,scu-pd" + - #power-domain-cells: Must be 1. Contains the Resource ID used by SCU commands. See detailed Resource ID list from: @@ -145,7 +148,7 @@ firmware { }; pd: imx8qx-pd { - compatible = "fsl,imx8qxp-scu-pd"; + compatible = "fsl,imx8qxp-scu-pd", "fsl,scu-pd"; #power-domain-cells = <1>; }; };
SCU power domain can be used in the same way by IMX8QXP and IMX8QM SoCs. Let's add a "fsl,scu-pd" fallback compatible string to allow other SoCs to reuse the common part. Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: Rob Herring <robh+dt@kernel.org> Cc: Shawn Guo <shawnguo@kernel.org> Cc: Sascha Hauer <kernel@pengutronix.de> Cc: Fabio Estevam <fabio.estevam@nxp.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: devicetree@vger.kernel.org Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com> --- Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)