Subject: [PATCH 1/4] clk: sunxi: Allwinner A20 output clock support

From: [email-masked] (Emilio López)
Date: Mon, 23 Dec 2013 13:13:47 -0300

Hi,

El 23/12/13 05:37, Chen-Yu Tsai escribi?:
> This patch adds support for the external clock outputs on the
> Allwinner A20 SoC. The clock outputs are similar to "module 0"
> type clocks, with different offsets and widths for clock factors.
>
> Signed-off-by: Chen-Yu Tsai <[email-masked]>

This patch looks good to me,

Acked-by: Emilio L?pez <[email-masked]>

> ---
>   drivers/clk/sunxi/clk-sunxi.c | 57 +++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 57 insertions(+)
>
> diff --git a/drivers/clk/sunxi/clk-sunxi.c b/drivers/clk/sunxi/clk-sunxi.c
> index 25d99b6..19d9e9e 100644
> --- a/drivers/clk/sunxi/clk-sunxi.c
> +++ b/drivers/clk/sunxi/clk-sunxi.c
> @@ -330,6 +330,47 @@ static void sun4i_get_mod0_factors(u32 *freq, u32 parent_rate,
>
>
>   /**
> + * sun7i_a20_get_out_factors() - calculates m, p factors for CLK_OUT_A/B
> + * CLK_OUT rate is calculated as follows
> + * rate = (parent_rate >> p) / (m + 1);
> + */
> +
> +static void sun7i_a20_get_out_factors(u32 *freq, u32 parent_rate,
> +				      u8 *n, u8 *k, u8 *m, u8 *p)
> +{
> +	u8 div, calcm, calcp;
> +
> +	/* These clocks can only divide, so we will never be able to achieve
> +	 * frequencies higher than the parent frequency */
> +	if (*freq > parent_rate)
> +		*freq = parent_rate;
> +
> +	div = parent_rate / *freq;
> +
> +	if (div < 32)
> +		calcp = 0;
> +	else if (div / 2 < 32)
> +		calcp = 1;
> +	else if (div / 4 < 32)
> +		calcp = 2;
> +	else
> +		calcp = 3;
> +
> +	calcm = DIV_ROUND_UP(div, 1 << calcp);
> +
> +	*freq = (parent_rate >> calcp) / calcm;
> +
> +	/* we were called to round the frequency, we can now return */
> +	if (n == NULL)
> +		return;
> +
> +	*m = calcm - 1;
> +	*p = calcp;
> +}
> +
> +
> +
> +/**
>    * sunxi_factors_clk_setup() - Setup function for factor clocks
>    */
>
> @@ -384,6 +425,14 @@ static struct clk_factors_config sun4i_mod0_config = {
>   	.pwidth = 2,
>   };
>
> +/* user manual says "n" but it's really "p" */
> +static struct clk_factors_config sun7i_a20_out_config = {
> +	.mshift = 8,
> +	.mwidth = 5,
> +	.pshift = 20,
> +	.pwidth = 2,
> +};
> +
>   static const struct factors_data sun4i_pll1_data __initconst = {
>   	.enable = 31,
>   	.table = &sun4i_pll1_config,
> @@ -414,6 +463,13 @@ static const struct factors_data sun4i_mod0_data __initconst = {
>   	.getter = sun4i_get_mod0_factors,
>   };
>
> +static const struct factors_data sun7i_a20_out_data __initconst = {
> +	.enable = 31,
> +	.mux = 24,
> +	.table = &sun7i_a20_out_config,
> +	.getter = sun7i_a20_get_out_factors,
> +};
> +
>   static struct clk * __init sunxi_factors_clk_setup(struct device_node *node,
>   						const struct factors_data *data)
>   {
> @@ -912,6 +968,7 @@ static const struct of_device_id clk_factors_match[] __initconst = {
>   	{.compatible = "allwinner,sun6i-a31-pll1-clk", .data = &sun6i_a31_pll1_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,},
>   	{}
>   };