From 9490107c16c8eaa35b07794e19d5d2eddea8e44b Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Emilio=20L=C3=B3pez?= Date: Sat, 14 Sep 2013 20:48:40 -0300 Subject: [PATCH] clk: sunxi: Implement muxable AHB clock MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit sun5i and sun7i have a mux to change the AHB clock parent, this commit adds support for it on the driver. Signed-off-by: Emilio López --- Documentation/devicetree/bindings/clock/sunxi.txt | 1 + drivers/clk/sunxi/clk-sunxi.c | 37 +++++++++++++++++++++++ 2 files changed, 38 insertions(+) diff --git a/Documentation/devicetree/bindings/clock/sunxi.txt b/Documentation/devicetree/bindings/clock/sunxi.txt index e840cb2..941bd93 100644 --- a/Documentation/devicetree/bindings/clock/sunxi.txt +++ b/Documentation/devicetree/bindings/clock/sunxi.txt @@ -15,6 +15,7 @@ Required properties: "allwinner,sun4i-axi-clk" - for the AXI clock "allwinner,sun4i-axi-gates-clk" - for the AXI gates "allwinner,sun4i-ahb-clk" - for the AHB clock + "allwinner,sun5i-a13-ahb-clk" - for the AHB clock on A13 "allwinner,sun4i-ahb-gates-clk" - for the AHB gates on A10 "allwinner,sun5i-a13-ahb-gates-clk" - for the AHB gates on A13 "allwinner,sun5i-a10s-ahb-gates-clk" - for the AHB gates on A10s diff --git a/drivers/clk/sunxi/clk-sunxi.c b/drivers/clk/sunxi/clk-sunxi.c index ea3edeb..625089b 100644 --- a/drivers/clk/sunxi/clk-sunxi.c +++ b/drivers/clk/sunxi/clk-sunxi.c @@ -249,7 +249,32 @@ static void sun4i_get_pll5_factors(u32 *freq, u32 parent_rate, *n = DIV_ROUND_UP(div, (*k+1)); } +/** + * sun5i_get_ahb_factors() - calculates p factor for AHB + * AHB rate is calculated as follows + * rate = parent_rate >> p + */ +static void sun5i_a13_get_ahb_factors(u32 *freq, u32 parent_rate, + u8 *n, u8 *k, u8 *m, u8 *p) +{ + u8 div; + + /* This clock can only divide, so we will never achieve a higher + * rate than the parent's */ + if (*freq > parent_rate) + *freq = parent_rate; + + /* Normalize value to a parent multiple */ + div = *freq / parent_rate; + *freq = parent_rate * div; + + /* we were called to round the frequency, we can now return */ + if (n == NULL) + return; + + *p = div; +} /** * sun4i_get_apb1_factors() - calculates m, p factors for APB1 @@ -375,6 +400,11 @@ struct factors_data { .kwidth = 2, }; +static struct clk_factors_config sun5i_a13_ahb_config = { + .pshift = 4, + .pwidth = 2, +}; + static struct clk_factors_config sun4i_apb1_config = { .mshift = 0, .mwidth = 5, @@ -408,6 +438,12 @@ struct factors_data { .getter = sun4i_get_pll5_factors, }; +static const struct factors_data sun5i_a13_ahb_data __initconst = { + .mux = 6, + .table = &sun5i_a13_ahb_config, + .getter = sun5i_a13_get_ahb_factors, +}; + static const struct factors_data sun4i_apb1_data __initconst = { .mux = 24, .table = &sun4i_apb1_config, @@ -913,6 +949,7 @@ static void __init sunxi_divs_clk_setup(struct device_node *node, 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,sun5i-a13-ahb-clk", .data = &sun5i_a13_ahb_data,}, {.compatible = "allwinner,sun4i-apb1-clk", .data = &sun4i_apb1_data,}, {.compatible = "allwinner,sun4i-mod0-clk", .data = &sun4i_mod0_data,}, {} -- 1.8.5.1