[PATCH] ARM: shmobile: r8a7794: Correct SDHI clock node names

[Geert Uytterhoeven]

Hi Simon,

On Thu, Jan 8, 2015 at 1:38 AM, Simon Horman <horms at verge.net.au> wrote:
> On Mon, Jan 05, 2015 at 10:41:14AM +0100, Geert Uytterhoeven wrote:
>> On Mon, Jan 5, 2015 at 1:44 AM, Simon Horman <horms+renesas at verge.net.au> wrote:
>> > diff --git a/arch/arm/boot/dts/r8a7794.dtsi b/arch/arm/boot/dts/r8a7794.dtsi
>> > index 8f78da5..9856e9c 100644
>> > --- a/arch/arm/boot/dts/r8a7794.dtsi
>> > +++ b/arch/arm/boot/dts/r8a7794.dtsi
>> > @@ -294,14 +294,14 @@
>> >                                              "lb", "qspi", "sdh", "sd0", "z";
>> >                 };
>> >                 /* Variable factor clocks */
>> > -               sd1_clk: sd2_clk at e6150078 {
>> > +               sd1_clk: sd1_clk at e6150078 {
>> >                         compatible = "renesas,r8a7794-div6-clock", "renesas,cpg-div6-clock";
>> >                         reg = <0 0xe6150078 0 4>;
>> >                         clocks = <&pll1_div2_clk>;
>> >                         #clock-cells = <0>;
>> >                         clock-output-names = "sd1";
>> >                 };
>> > -               sd2_clk: sd3_clk at e615007c {
>> > +               sd2_clk: sd2_clk at e615007c {
>> >                         compatible = "renesas,r8a7794-div6-clock", "renesas,cpg-div6-clock";
>> >                         reg = <0 0xe615007c 0 4>;
>> >                         clocks = <&pll1_div2_clk>;
>>
>> According to the documentation, SDCKCR is 0xe6150074, not ..78,
>> SD2CKCR is 0xe6150078, not ..7c.
>> For reference SD3CKCR is 0xe615026c.
>>
>> Note that r8a7791.dtsi also has the mismatches between the labels and node
>> names.
>>
>> The discrepancy is caused by the different number of SDHI modules in the
>> different SoCs of the R-Car Gen2 family.
>>
>>   - r8a7790 has hardware modules SDHI0, SDHI1, SDHI2, and SDHI3.
>>   - r8a7791 and r8a7794 have hardware modules SDHI0, SDHI2, and SDHI3,
>>     but call the last two instances SDHI1 and SDHI2, while the clock registers
>>     are not renumbered.
>>     So instance SDHI1 uses SD2CKCR, and instance SDHI2 uses SD3CKCR, right?
>
> I had not noticed, but yes that does seem to be the case.
>
>> That means the node names are actually correct. But the register value and
>> unit address for the second clock are still wrong, they should be (0x)e615007c,
>
> Ok, that makes sense. But in that the labels want updating, right?

Yes, if the labels are supposed to refer to the clk instance (and not the
SDHI instance).

>> cfr. in r8a7791.dtsi.
>>
>> Note that IMHO the clock-output-names are wrong, for both r8a7791 and r8a7794,
>> as the hardware documentation calls these "sd2" and "sd3", not "sd1" and "sd2".
>
> Excellent. I think we can easily change that for the r8a7794 as the
> nodes aren't being consumed nor have been part of a release. But I'm
> less sure about a path forward for the r8a7791. What are your thoughts?

While the clock names are user-visible through /sysfs, I don't think anything
relies on them. Their users (in DT) refer to the labels in DT.
Or am I missing something?

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds