openwrt/target/linux/sunxi/patches-3.12/115-clk-sunxi-muxable-ahb-c...

103 lines
3.4 KiB
Diff

From 147a46beeb49c6baabb85126d570f330a2ba7cad Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Emilio=20L=C3=B3pez?= <emilio@elopez.com.ar>
Date: Sat, 14 Sep 2013 20:48:40 -0300
Subject: [PATCH] clk: sunxi: Implement muxable AHB clock
MIME-Version: 1.0
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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 <emilio@elopez.com.ar>
---
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 0ecaa18..360d705 100644
--- a/drivers/clk/sunxi/clk-sunxi.c
+++ b/drivers/clk/sunxi/clk-sunxi.c
@@ -240,7 +240,32 @@ 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
@@ -366,6 +391,11 @@ 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,
@@ -399,6 +429,12 @@ 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,
@@ -842,6 +878,7 @@ 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