Subject: [PATCH v2 1/3] clocksource: sh_cmt: Document SoC specific bindings

From: [email-masked] (Laurent Pinchart)
Date: Thu, 04 Sep 2014 09:51:27 +0300

Hi Simon,

Thank you for the patch.

On Thursday 04 September 2014 09:55:19 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
> 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 <[email-masked]>
> Acked-by: Geert Uytterhoeven <[email-masked]>
> Acked-by: Mark Rutland <[email-masked]>
> 
> ---
> * 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.

If renesas,cmt-48-gen2 is a fallback for renesas,cmt-48-gen2, we'll have an 
infinite loop :-) I suppose you meant

		This is a fallback for the renesas,cmt-48-r8a73a4,
		renesas,cmt-48-r8a7790 and renesas,cmt-48-r8a7791 entries.

With that change,

Acked-by: Laurent Pinchart <[email-masked]>

>    - 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 at 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>;

-- 
Regards,

Laurent Pinchart