[PATCH v4 1/5] clk: sunxi: Add support for PLL6 on the A31

Mike Turquette mturquette at linaro.org
Wed Feb 5 09:51:49 EST 2014


Quoting Maxime Ripard (2014-02-05 05:05:03)
> The A31 has a slightly different PLL6 clock. Add support for this new clock in
> our driver.
> 
> Signed-off-by: Maxime Ripard <maxime.ripard at free-electrons.com>

Looks good to me.

Regards,
Mike

> ---
>  Documentation/devicetree/bindings/clock/sunxi.txt |  1 +
>  drivers/clk/sunxi/clk-sunxi.c                     | 45 +++++++++++++++++++++++
>  2 files changed, 46 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/clock/sunxi.txt b/Documentation/devicetree/bindings/clock/sunxi.txt
> index c2cb762..954845c 100644
> --- a/Documentation/devicetree/bindings/clock/sunxi.txt
> +++ b/Documentation/devicetree/bindings/clock/sunxi.txt
> @@ -11,6 +11,7 @@ Required properties:
>         "allwinner,sun6i-a31-pll1-clk" - for the main PLL clock on A31
>         "allwinner,sun4i-pll5-clk" - for the PLL5 clock
>         "allwinner,sun4i-pll6-clk" - for the PLL6 clock
> +       "allwinner,sun6i-a31-pll6-clk" - for the PLL6 clock on A31
>         "allwinner,sun4i-cpu-clk" - for the CPU multiplexer clock
>         "allwinner,sun4i-axi-clk" - for the AXI clock
>         "allwinner,sun4i-axi-gates-clk" - for the AXI gates
> diff --git a/drivers/clk/sunxi/clk-sunxi.c b/drivers/clk/sunxi/clk-sunxi.c
> index abb6c5a..0c05c2d 100644
> --- a/drivers/clk/sunxi/clk-sunxi.c
> +++ b/drivers/clk/sunxi/clk-sunxi.c
> @@ -249,7 +249,38 @@ static void sun4i_get_pll5_factors(u32 *freq, u32 parent_rate,
>         *n = DIV_ROUND_UP(div, (*k+1));
>  }
>  
> +/**
> + * sun6i_a31_get_pll6_factors() - calculates n, k factors for A31 PLL6
> + * PLL6 rate is calculated as follows
> + * rate = parent_rate * n * (k + 1) / 2
> + * parent_rate is always 24Mhz
> + */
> +
> +static void sun6i_a31_get_pll6_factors(u32 *freq, u32 parent_rate,
> +                                      u8 *n, u8 *k, u8 *m, u8 *p)
> +{
> +       u8 div;
> +
> +       /*
> +        * We always have 24MHz / 2, so we can just say that our
> +        * parent clock is 12MHz.
> +        */
> +       parent_rate = parent_rate / 2;
> +
> +       /* Normalize value to a parent_rate multiple (24M / 2) */
> +       div = *freq / parent_rate;
> +       *freq = parent_rate * div;
> +
> +       /* we were called to round the frequency, we can now return */
> +       if (n == NULL)
> +               return;
> +
> +       *k = div / 32;
> +       if (*k > 3)
> +               *k = 3;
>  
> +       *n = DIV_ROUND_UP(div, (*k+1));
> +}
>  
>  /**
>   * sun4i_get_apb1_factors() - calculates m, p factors for APB1
> @@ -416,6 +447,13 @@ static struct clk_factors_config sun4i_pll5_config = {
>         .kwidth = 2,
>  };
>  
> +static struct clk_factors_config sun6i_a31_pll6_config = {
> +       .nshift = 8,
> +       .nwidth = 5,
> +       .kshift = 4,
> +       .kwidth = 2,
> +};
> +
>  static struct clk_factors_config sun4i_apb1_config = {
>         .mshift = 0,
>         .mwidth = 5,
> @@ -457,6 +495,12 @@ static const struct factors_data sun4i_pll5_data __initconst = {
>         .getter = sun4i_get_pll5_factors,
>  };
>  
> +static const struct factors_data sun6i_a31_pll6_data __initconst = {
> +       .enable = 31,
> +       .table = &sun6i_a31_pll6_config,
> +       .getter = sun6i_a31_get_pll6_factors,
> +};
> +
>  static const struct factors_data sun4i_apb1_data __initconst = {
>         .table = &sun4i_apb1_config,
>         .getter = sun4i_get_apb1_factors,
> @@ -972,6 +1016,7 @@ free_clkdata:
>  static const struct of_device_id clk_factors_match[] __initconst = {
>         {.compatible = "allwinner,sun4i-pll1-clk", .data = &sun4i_pll1_data,},
>         {.compatible = "allwinner,sun6i-a31-pll1-clk", .data = &sun6i_a31_pll1_data,},
> +       {.compatible = "allwinner,sun6i-a31-pll6-clk", .data = &sun6i_a31_pll6_data,},
>         {.compatible = "allwinner,sun4i-apb1-clk", .data = &sun4i_apb1_data,},
>         {.compatible = "allwinner,sun4i-mod0-clk", .data = &sun4i_mod0_data,},
>         {.compatible = "allwinner,sun7i-a20-out-clk", .data = &sun7i_a20_out_data,},
> -- 
> 1.8.4.2
> 



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