Re: [PATCH] dt-bindings: clk: renesas: Update {ETH,SDHI,USB} CPG Clock Definitions

[Geert Uytterhoeven <geert@linux-m68k.org>]

Hi Biju,

On Wed, Jun 16, 2021 at 1:18 PM Biju Das <biju.das.jz@bp.renesas.com> wrote:
> Update {ETH, SDHI, USB} clock definitions, as they need special
> handling.
>
> ETH has 2 clocks controlled by single bit.
> USB has 4 clocks pclock is shared by USB Ch0 and USB Ch1.
> SDHI has 4 clocks.
>
> Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
> Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Thanks for your patch!

> --- a/include/dt-bindings/clock/r9a07g044-cpg.h
> +++ b/include/dt-bindings/clock/r9a07g044-cpg.h
> @@ -39,51 +39,61 @@
>  #define R9A07G044_CLK_SYSC             4
>  #define R9A07G044_CLK_MTU              5
>  #define R9A07G044_CLK_GPT              6
> -#define R9A07G044_CLK_ETH0             7
> -#define R9A07G044_CLK_ETH1             8
> -#define R9A07G044_CLK_I2C0             9
> -#define R9A07G044_CLK_I2C1             10
> -#define R9A07G044_CLK_I2C2             11
> -#define R9A07G044_CLK_I2C3             12
> -#define R9A07G044_CLK_SCIF0            13
> -#define R9A07G044_CLK_SCIF1            14
> -#define R9A07G044_CLK_SCIF2            15
> -#define R9A07G044_CLK_SCIF3            16
> -#define R9A07G044_CLK_SCIF4            17
> -#define R9A07G044_CLK_SCI0             18
> -#define R9A07G044_CLK_SCI1             19
> -#define R9A07G044_CLK_GPIO             20
> -#define R9A07G044_CLK_SDHI0            21
> -#define R9A07G044_CLK_SDHI1            22
> -#define R9A07G044_CLK_USB0             23
> -#define R9A07G044_CLK_USB1             24
> -#define R9A07G044_CLK_CANFD            25
> -#define R9A07G044_CLK_SSI0             26
> -#define R9A07G044_CLK_SSI1             27
> -#define R9A07G044_CLK_SSI2             28
> -#define R9A07G044_CLK_SSI3             29
> -#define R9A07G044_CLK_MHU              30
> -#define R9A07G044_CLK_OSTM0            31
> -#define R9A07G044_CLK_OSTM1            32
> -#define R9A07G044_CLK_OSTM2            33
> -#define R9A07G044_CLK_WDT0             34
> -#define R9A07G044_CLK_WDT1             35
> -#define R9A07G044_CLK_WDT2             36
> -#define R9A07G044_CLK_WDT_PON          37
> -#define R9A07G044_CLK_GPU              38
> -#define R9A07G044_CLK_ISU              39
> -#define R9A07G044_CLK_H264             40
> -#define R9A07G044_CLK_CRU              41
> -#define R9A07G044_CLK_MIPI_DSI         42
> -#define R9A07G044_CLK_LCDC             43
> -#define R9A07G044_CLK_SRC              44
> -#define R9A07G044_CLK_RSPI0            45
> -#define R9A07G044_CLK_RSPI1            46
> -#define R9A07G044_CLK_RSPI2            47
> -#define R9A07G044_CLK_ADC              48
> -#define R9A07G044_CLK_TSU_PCLK         49
> -#define R9A07G044_CLK_SPI              50
> -#define R9A07G044_CLK_MIPI_DSI_V       51
> -#define R9A07G044_CLK_MIPI_DSI_PIN     52
> +#define ETH0_CLK_AXI                   7
> +#define ETH0_CLK_CHI                   8
> +#define ETH1_CLK_AXI                   9
> +#define ETH1_CLK_CHI                   10

R9A07G044_ETH0_CLK_AXI etc.?

> +#define R9A07G044_CLK_I2C0             11
> +#define R9A07G044_CLK_I2C1             12
> +#define R9A07G044_CLK_I2C2             13
> +#define R9A07G044_CLK_I2C3             14
> +#define R9A07G044_CLK_SCIF0            15
> +#define R9A07G044_CLK_SCIF1            16
> +#define R9A07G044_CLK_SCIF2            17
> +#define R9A07G044_CLK_SCIF3            18
> +#define R9A07G044_CLK_SCIF4            19
> +#define R9A07G044_CLK_SCI0             20
> +#define R9A07G044_CLK_SCI1             21
> +#define R9A07G044_CLK_GPIO             22
> +#define R9A07G044_CLK_SDHI0_IMCLK      23
> +#define R9A07G044_CLK_SDHI0_IMCLK2     24
> +#define R9A07G044_CLK_SDHI0_CLK_HS     25
> +#define R9A07G044_CLK_SDHI0_ACLK       26
> +#define R9A07G044_CLK_SDHI1_IMCLK      27
> +#define R9A07G044_CLK_SDHI1_IMCLK2     28
> +#define R9A07G044_CLK_SDHI1_CLK_HS     29
> +#define R9A07G044_CLK_SDHI1_ACLK       30
> +#define R9A07G044_CLK_USB_U2H0_HCLK    31
> +#define R9A07G044_CLK_USB_U2H1_HCLK    32
> +#define R9A07G044_CLK_HSUSB            33
> +#define R9A07G044_CLK_USB_PCLK         34

I think we should use the opportunity to
  1. Split the remaining module clocks like R9A07G044_CLK_IA55 and
     R9A07G044_CLK_DMAC,
  2. Rename the definitions to match the "Clock Name" column in the
     RZG2L clock list, with an "R9A07G044_" prefix,
  3. Add all missing clocks, as listed in the RZG2L clock list.
This will prevent similar issues from popping up later, when the DT
bindings clock list is part of a released kernel version, and becomes
cast in stone and append-only (so yes, step 3 could be postponed).

Do you agree?

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@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