On Wed, Sep 03, 2014 at 02:27:25AM +0100, Simon Horman wrote:
> Hi Mark,
>
> On Wed, Aug 27, 2014 at 10:51:03AM +0100, Mark Rutland wrote:
> > Hi Simon,
> >
> > On Wed, Aug 27, 2014 at 06:28:18AM +0100, Simon Horman wrote:
> > > In general Renesas hardware is not documented to the extent
> > > where the relationship between IP blocks on different SoCs can be assumed
> > > although they may appear to operate the same way. Furthermore the
> > > documentation typically does not specify a version for individual
> > > IP blocks. For these reasons a convention of using the SoC name in place
> > > of a version and providing SoC-specific compat strings has been adopted.
> > >
> > > Although not universally liked this convention is used in the bindings
> > > for the drivers a number of drivers for Renesas hardware. The purpose
> > > of this patch is to update the Renesas R-Car Compare Match Timer (CMT)
> > > driver to follow this convention.
> >
> > Having really specific strings to give us the flexibility if necessary
> > makes sense, so I the addition of the strings below is fine.
> >
> > I see in the example update the existing "renesas,cmt-48-gen2" string
> > remains. I take it we expect that as a fallback in the compatible list
> > for all of the new strings, and the driver can jsut match on that for
> > the moment?
> >
> > If so, it would be nice to be more explicit as to what we expect as
> > fallback compatible entries.
>
> Yes, that is the desired behaviour.
> Would this address your concerns?
> It incorporates some suggestions made by Geert Uytterhoeven
> and explicitly talks about fallback entries.
>
> From: Simon Horman <horms+renesas@xxxxxxxxxxxx>
>
> [PATCH v1.1] clocksource: sh_cmt: Document SoC specific bindings
>
> In general Renesas hardware is not documented to the extent
> where the relationship between IP blocks on different SoCs can be assumed
> although they may appear to operate the same way. Furthermore the
> documentation typically does not specify a version for individual
> IP blocks. For these reasons a convention of using the SoC name in place
> of a version and providing SoC-specific compat strings has been adopted.
>
> Although not universally liked this convention is used in the bindings for
> a number of drivers for Renesas hardware. The purpose of this patch is to
> update the Renesas R-Car Compare Match Timer (CMT) driver to follow this
> convention.
>
> Signed-off-by: Simon Horman <horms+renesas@xxxxxxxxxxxx>
> Acked-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
I'm happy with this.
Acked-by: Mark Rutland <mark.rutland@xxxxxxx>
Mark.
>
> ---
> * I plan to follow up with patches to use these new bindings in the
> dtsi files for the affected SoCs.
>
> v2
> * Reorder compat entries so more-specific entries and their fallbacks
> are grouped with the fallback entry coming last.
> * Explicitly document fallback
> ---
> .../devicetree/bindings/timer/renesas,cmt.txt | 44 +++++++++++++++++++---
> 1 file changed, 38 insertions(+), 6 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/timer/renesas,cmt.txt b/Documentation/devicetree/bindings/timer/renesas,cmt.txt
> index a17418b..7b44f4b 100644
> --- a/Documentation/devicetree/bindings/timer/renesas,cmt.txt
> +++ b/Documentation/devicetree/bindings/timer/renesas,cmt.txt
> @@ -11,15 +11,47 @@ datasheets.
>
> Required Properties:
>
> - - compatible: must contain one of the following.
> - - "renesas,cmt-32" for the 32-bit CMT
> + - compatible: must contain one or more of the following:
> + - "renesas,cmt-32-r8a7740" for the R8a7740 32-bit CMT
> + (CMT0)
> + - "renesas,cmt-32-sh7372" for the SH7372 32-bit CMT
> + (CMT0)
> + - "renesas,cmt-32-sh73a0" for the SH73a0 32-bit CMT
> + (CMT0)
> + - "renesas,cmt-32" for all 32-bit CMT without fast clock support
> (CMT0 on sh7372, sh73a0 and r8a7740)
> - - "renesas,cmt-32-fast" for the 32-bit CMT with fast clock support
> + This is a fallback for the above renesas,cmt-32-* entries.
> +
> + - "renesas,cmt-32-fast-r8a7740" for the R8A7740 32-bit CMT with fast
> + clock support (CMT[234])
> + - "renesas,cmt-32-fast-sh7372" for the SH7372 32-bit CMT with fast
> + clock support (CMT[234])
> + - "renesas,cmt-32-fast-sh73a0" for the SH73A0 32-bit CMT with fast
> + clock support (CMT[234])
> + - "renesas,cmt-32-fast" for all 32-bit CMT with fast clock support
> (CMT[234] on sh7372, sh73a0 and r8a7740)
> - - "renesas,cmt-48" for the 48-bit CMT
> + This is a fallback for the above renesas,cmt-32-fast-* entries.
> +
> + - "renesas,cmt-48-sh7372" for the SH7372 48-bit CMT
> + (CMT1)
> + - "renesas,cmt-48-sh73a0" for the SH73A0 48-bit CMT
> + (CMT1)
> + - "renesas,cmt-48-r8a7740" for the R8A7740 48-bit CMT
> + (CMT1)
> + - "renesas,cmt-48" for all non-second generation 48-bit CMT
> (CMT1 on sh7372, sh73a0 and r8a7740)
> - - "renesas,cmt-48-gen2" for the second generation 48-bit CMT
> + This is a fallback for the above renesas,cmt-48-* entries.
> +
> + - "renesas,cmt-48-r8a73a4" for the R8A73A4 48-bit CMT
> + (CMT[01])
> + - "renesas,cmt-48-r8a7790" for the R8A7790 48-bit CMT
> + (CMT[01])
> + - "renesas,cmt-48-r8a7791" for the R8A7791 48-bit CMT
> + (CMT[01])
> + - "renesas,cmt-48-gen2" for all second generation 48-bit CMT
> (CMT[01] on r8a73a4, r8a7790 and r8a7791)
> + This is a fallback for the renesas,cmt-48-r8a73a4,
> + renesas,cmt-48-r8a7790 and renesas,cmt-48-gen2 entries.
>
> - reg: base address and length of the registers block for the timer module.
> - interrupts: interrupt-specifier for the timer, one per channel.
> @@ -36,7 +68,7 @@ Example: R8A7790 (R-Car H2) CMT0 node
> them channels 0 and 1 in the documentation.
>
> cmt0: timer@ffca0000 {
> - compatible = "renesas,cmt-48-gen2";
> + compatible = "renesas,cmt-48-r8a7790", "renesas,cmt-48-gen2";
> reg = <0 0xffca0000 0 0x1004>;
> interrupts = <0 142 IRQ_TYPE_LEVEL_HIGH>,
> <0 142 IRQ_TYPE_LEVEL_HIGH>;
> --
> 2.0.1
>
>
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