[1/3] dt-bindings: perf: fsl-imx-ddr: Add i.MX95 compatible

Message ID 20231127073208.1055466-1-xu.yang_2@nxp.com
State New
Headers
Series [1/3] dt-bindings: perf: fsl-imx-ddr: Add i.MX95 compatible |

Commit Message

Xu Yang Nov. 27, 2023, 7:32 a.m. UTC
  i.MX95 has a more precise counting capability than i.MX93. This will add
a compatible for it.

Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
---
 Documentation/devicetree/bindings/perf/fsl-imx-ddr.yaml | 1 +
 1 file changed, 1 insertion(+)
  

Comments

Conor Dooley Nov. 27, 2023, 5:36 p.m. UTC | #1
On Mon, Nov 27, 2023 at 03:32:06PM +0800, Xu Yang wrote:
> i.MX95 has a more precise counting capability than i.MX93. This will add
> a compatible for it.

It is hard to tell from this comment, but I figure this "more precise
capability" is not an option you can enable, but instead makes the
programming model of this device different to that of the imx93?

Thanks,
Conor.

> 
> Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
> ---
>  Documentation/devicetree/bindings/perf/fsl-imx-ddr.yaml | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/Documentation/devicetree/bindings/perf/fsl-imx-ddr.yaml b/Documentation/devicetree/bindings/perf/fsl-imx-ddr.yaml
> index e9fad4b3de68..1bc7bf1c8368 100644
> --- a/Documentation/devicetree/bindings/perf/fsl-imx-ddr.yaml
> +++ b/Documentation/devicetree/bindings/perf/fsl-imx-ddr.yaml
> @@ -20,6 +20,7 @@ properties:
>            - fsl,imx8mn-ddr-pmu
>            - fsl,imx8mp-ddr-pmu
>            - fsl,imx93-ddr-pmu
> +          - fsl,imx95-ddr-pmu
>        - items:
>            - enum:
>                - fsl,imx8mm-ddr-pmu
> -- 
> 2.34.1
>
  
Xu Yang Dec. 1, 2023, 6:41 a.m. UTC | #2
Hi Conor,

> 
> On Mon, Nov 27, 2023 at 03:32:06PM +0800, Xu Yang wrote:
> > i.MX95 has a more precise counting capability than i.MX93. This will add
> > a compatible for it.
> 
> It is hard to tell from this comment, but I figure this "more precise
> capability" is not an option you can enable, but instead makes the
> programming model of this device different to that of the imx93?

Actually, imx95 is compatible with imx93 except AXI ID filter capability.
But for AXI ID filter, imx95 is using different registers and bits from
imx93 for filter configuration. To distinguish them, I need use different
compatible because programming model cannot recognize which device is
running.

compatible = "fsl,imx95-ddr-pmu";
compatible = "fsl,imx95-ddr-pmu", "fsl,imx93-ddr-pmu";

Both above compatible is okay for me. Therefore, "fsl,imx95-ddr-pmu" is needed.

Thanks,
Xu Yang

> 
> Thanks,
> Conor.
> 
> >
> > Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
> > ---
> >  Documentation/devicetree/bindings/perf/fsl-imx-ddr.yaml | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/Documentation/devicetree/bindings/perf/fsl-imx-ddr.yaml b/Documentation/devicetree/bindings/perf/fsl-
> imx-ddr.yaml
> > index e9fad4b3de68..1bc7bf1c8368 100644
> > --- a/Documentation/devicetree/bindings/perf/fsl-imx-ddr.yaml
> > +++ b/Documentation/devicetree/bindings/perf/fsl-imx-ddr.yaml
> > @@ -20,6 +20,7 @@ properties:
> >            - fsl,imx8mn-ddr-pmu
> >            - fsl,imx8mp-ddr-pmu
> >            - fsl,imx93-ddr-pmu
> > +          - fsl,imx95-ddr-pmu
> >        - items:
> >            - enum:
> >                - fsl,imx8mm-ddr-pmu
> > --
> > 2.34.1
> >
  
Conor Dooley Dec. 1, 2023, 4:16 p.m. UTC | #3
On Fri, Dec 01, 2023 at 06:41:59AM +0000, Xu Yang wrote:
> Hi Conor,
> 
> > 
> > On Mon, Nov 27, 2023 at 03:32:06PM +0800, Xu Yang wrote:
> > > i.MX95 has a more precise counting capability than i.MX93. This will add
> > > a compatible for it.
> > 
> > It is hard to tell from this comment, but I figure this "more precise
> > capability" is not an option you can enable, but instead makes the
> > programming model of this device different to that of the imx93?
> 
> Actually, imx95 is compatible with imx93 except AXI ID filter capability.
> But for AXI ID filter, imx95 is using different registers and bits from
> imx93 for filter configuration.

This sounds like it conflicts with...

> To distinguish them, I need use different
> compatible because programming model cannot recognize which device is
> running.
> 
> compatible = "fsl,imx95-ddr-pmu";

> compatible = "fsl,imx95-ddr-pmu", "fsl,imx93-ddr-pmu";

...this. If drivers for the imx93 need changes to work on the imx95,
then `compatible = "fsl,imx95-ddr-pmu", "fsl,imx93-ddr-pmu";` cannot be
used. If they will work, with only the new imx95 features being
non-functional, then you can use it.

> Both above compatible is okay for me. Therefore, "fsl,imx95-ddr-pmu" is needed.
  
Xu Yang Dec. 6, 2023, 1:42 a.m. UTC | #4
Hi Hi Conor,

> 
> On Fri, Dec 01, 2023 at 06:41:59AM +0000, Xu Yang wrote:
> > Hi Conor,
> >
> > >
> > > On Mon, Nov 27, 2023 at 03:32:06PM +0800, Xu Yang wrote:
> > > > i.MX95 has a more precise counting capability than i.MX93. This will add
> > > > a compatible for it.
> > >
> > > It is hard to tell from this comment, but I figure this "more precise
> > > capability" is not an option you can enable, but instead makes the
> > > programming model of this device different to that of the imx93?
> >
> > Actually, imx95 is compatible with imx93 except AXI ID filter capability.
> > But for AXI ID filter, imx95 is using different registers and bits from
> > imx93 for filter configuration.
> 
> This sounds like it conflicts with...
> 
> > To distinguish them, I need use different
> > compatible because programming model cannot recognize which device is
> > running.
> >
> > compatible = "fsl,imx95-ddr-pmu";
> 
> > compatible = "fsl,imx95-ddr-pmu", "fsl,imx93-ddr-pmu";
> 
> ...this. If drivers for the imx93 need changes to work on the imx95,
> then `compatible = "fsl,imx95-ddr-pmu", "fsl,imx93-ddr-pmu";` cannot be
> used. If they will work, with only the new imx95 features being
> non-functional, then you can use it.

Yes, it is. When compatible = "fsl,imx95-ddr-pmu", "fsl,imx93-ddr-pmu" is used,
only the new imx95 features is not functional, other basic function works for
both imx95 and imx93.

Thanks,
Xu Yang

> 
> > Both above compatible is okay for me. Therefore, "fsl,imx95-ddr-pmu" is needed.
  

Patch

diff --git a/Documentation/devicetree/bindings/perf/fsl-imx-ddr.yaml b/Documentation/devicetree/bindings/perf/fsl-imx-ddr.yaml
index e9fad4b3de68..1bc7bf1c8368 100644
--- a/Documentation/devicetree/bindings/perf/fsl-imx-ddr.yaml
+++ b/Documentation/devicetree/bindings/perf/fsl-imx-ddr.yaml
@@ -20,6 +20,7 @@  properties:
           - fsl,imx8mn-ddr-pmu
           - fsl,imx8mp-ddr-pmu
           - fsl,imx93-ddr-pmu
+          - fsl,imx95-ddr-pmu
       - items:
           - enum:
               - fsl,imx8mm-ddr-pmu