AHB1 on A83T is similar to ahb1 on A31, except parents are different. clock index 0b1x is PLL6. Signed-off-by: Vishnu Patekar <vishnupatekar0510@xxxxxxxxx> Acked-by: Chen-Yu Tsai <wens@xxxxxxxx> Acked-by: Rob Herring <robh@xxxxxxxxxx> --- Documentation/devicetree/bindings/clock/sunxi.txt | 1 + drivers/clk/sunxi/clk-sunxi.c | 76 +++++++++++++++++++++++ 2 files changed, 77 insertions(+) diff --git a/Documentation/devicetree/bindings/clock/sunxi.txt b/Documentation/devicetree/bindings/clock/sunxi.txt index c09f59b..2ee7841 100644 --- a/Documentation/devicetree/bindings/clock/sunxi.txt +++ b/Documentation/devicetree/bindings/clock/sunxi.txt @@ -29,6 +29,7 @@ Required properties: "allwinner,sun6i-a31-ar100-clk" - for the AR100 on A31 "allwinner,sun9i-a80-cpus-clk" - for the CPUS on A80 "allwinner,sun6i-a31-ahb1-clk" - for the AHB1 clock on A31 + "allwinner,sun8i-a83t-ahb1-clk" - for the AHB1 clock on A83T "allwinner,sun8i-h3-ahb2-clk" - for the AHB2 clock on H3 "allwinner,sun6i-a31-ahb1-gates-clk" - for the AHB1 gates on A31 "allwinner,sun8i-a23-ahb1-gates-clk" - for the AHB1 gates on A23 diff --git a/drivers/clk/sunxi/clk-sunxi.c b/drivers/clk/sunxi/clk-sunxi.c index 99f60ef..0ae1f09 100644 --- a/drivers/clk/sunxi/clk-sunxi.c +++ b/drivers/clk/sunxi/clk-sunxi.c @@ -344,6 +344,67 @@ static void sun6i_ahb1_recalc(struct factors_request *req) req->rate >>= req->p; } +#define SUN8I_A83T_AHB1_PARENT_PLL6 2 +/** + * sun8i_a83t_get_ahb_factors() - calculates m, p factors for AHB + * AHB rate is calculated as follows + * rate = parent_rate >> p + * + * if parent is pll6, then + * parent_rate = pll6 rate / (m + 1) + */ + +static void sun8i_a83t_get_ahb1_factors(struct factors_request *req) +{ + u8 div, calcp, calcm = 1; + + /* + * clock can only divide, so we will never be able to achieve + * frequencies higher than the parent frequency + */ + if (req->parent_rate && req->rate > req->parent_rate) + req->rate = req->parent_rate; + + div = DIV_ROUND_UP(req->parent_rate, req->rate); + + /* calculate pre-divider if parent is pll6 */ + if (req->parent_index >= SUN8I_A83T_AHB1_PARENT_PLL6) { + if (div < 4) + calcp = 0; + else if (div / 2 < 4) + calcp = 1; + else if (div / 4 < 4) + calcp = 2; + else + calcp = 3; + + calcm = DIV_ROUND_UP(div, 1 << calcp); + } else { + calcp = __roundup_pow_of_two(div); + calcp = calcp > 3 ? 3 : calcp; +} + + req->rate = (req->parent_rate / calcm) >> calcp; + req->p = calcp; + req->m = calcm - 1; +} + +/** +* sun8i_a83t_ahb1_recalc() - calculates AHB clock rate from m, p factors and +* parent index +*/ +static void sun8i_a83t_ahb1_recalc(struct factors_request *req) +{ + req->rate = req->parent_rate; + +/* apply pre-divider first if parent is pll6 */ + if (req->parent_index >= SUN6I_AHB1_PARENT_PLL6) + req->rate /= req->m + 1; + + /* clk divider */ + req->rate >>= req->p; +} + /** * sun4i_get_apb1_factors() - calculates m, p factors for APB1 * APB1 rate is calculated as follows @@ -555,6 +616,14 @@ static const struct factors_data sun6i_ahb1_data __initconst = { .recalc = sun6i_ahb1_recalc, }; +static const struct factors_data sun8i_a83t_ahb1_data __initconst = { + .mux = 12, + .muxmask = BIT(1) | BIT(0), + .table = &sun6i_ahb1_config, + .getter = sun8i_a83t_get_ahb1_factors, + .recalc = sun8i_a83t_ahb1_recalc, +}; + static const struct factors_data sun4i_apb1_data __initconst = { .mux = 24, .muxmask = BIT(1) | BIT(0), @@ -627,6 +696,13 @@ static void __init sun6i_ahb1_clk_setup(struct device_node *node) CLK_OF_DECLARE(sun6i_a31_ahb1, "allwinner,sun6i-a31-ahb1-clk", sun6i_ahb1_clk_setup); +static void __init sun8i_a83t_ahb1_clk_setup(struct device_node *node) +{ + sunxi_factors_clk_setup(node, &sun8i_a83t_ahb1_data); +} +CLK_OF_DECLARE(sun8i_a83t_ahb1, "allwinner,sun8i-a83t-ahb1-clk", + sun8i_a83t_ahb1_clk_setup); + static void __init sun4i_apb1_clk_setup(struct device_node *node) { sunxi_factors_clk_setup(node, &sun4i_apb1_data); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html