[PATCH 1/4] clk: sunxi: Add support for PLL6 on the A31

From: Maxime Ripard
Date: Thu Jan 16 2014 - 12:16:12 EST


The A31 has a slightly different PLL6 clock. Add support for this new clock in
our driver.

Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>
---
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 659e4ea..990ad5d 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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