[PATCH 1/2] clk: keystone: add support for post divider register for main pll
Murali Karicheri
m-karicheri2 at ti.com
Fri May 29 09:04:12 PDT 2015
Main PLL controller has post divider bits in a separate register in
pll controller. Use the value from this register instead of fixed
divider when available.
Signed-off-by: Murali Karicheri <m-karicheri2 at ti.com>
---
.../devicetree/bindings/clock/keystone-pll.txt | 8 ++++----
drivers/clk/keystone/pll.c | 20 ++++++++++++++++++--
2 files changed, 22 insertions(+), 6 deletions(-)
diff --git a/Documentation/devicetree/bindings/clock/keystone-pll.txt b/Documentation/devicetree/bindings/clock/keystone-pll.txt
index 225990f..47570d2 100644
--- a/Documentation/devicetree/bindings/clock/keystone-pll.txt
+++ b/Documentation/devicetree/bindings/clock/keystone-pll.txt
@@ -15,8 +15,8 @@ Required properties:
- compatible : shall be "ti,keystone,main-pll-clock" or "ti,keystone,pll-clock"
- clocks : parent clock phandle
- reg - pll control0 and pll multipler registers
-- reg-names : control and multiplier. The multiplier is applicable only for
- main pll clock
+- reg-names : control, multiplier and post-divider. The multiplier and
+ post-divider registers are applicable only for main pll clock
- fixed-postdiv : fixed post divider value. If absent, use clkod register bits
for postdiv
@@ -25,8 +25,8 @@ Example:
#clock-cells = <0>;
compatible = "ti,keystone,main-pll-clock";
clocks = <&refclksys>;
- reg = <0x02620350 4>, <0x02310110 4>;
- reg-names = "control", "multiplier";
+ reg = <0x02620350 4>, <0x02310110 4>, <0x02310108 4>;
+ reg-names = "control", "multiplier", "post-divider";
fixed-postdiv = <2>;
};
diff --git a/drivers/clk/keystone/pll.c b/drivers/clk/keystone/pll.c
index 0dd8a4b..4a375ea 100644
--- a/drivers/clk/keystone/pll.c
+++ b/drivers/clk/keystone/pll.c
@@ -37,7 +37,8 @@
* Main PLL or any other PLLs in the device such as ARM PLL, DDR PLL
* or PA PLL available on keystone2. These PLLs are controlled by
* this register. Main PLL is controlled by a PLL controller.
- * @pllm: PLL register map address
+ * @pllm: PLL register map address for multiplier bits
+ * @pllod: PLL register map address for post divider bits
* @pll_ctl0: PLL controller map address
* @pllm_lower_mask: multiplier lower mask
* @pllm_upper_mask: multiplier upper mask
@@ -53,6 +54,7 @@ struct clk_pll_data {
u32 phy_pllm;
u32 phy_pll_ctl0;
void __iomem *pllm;
+ void __iomem *pllod;
void __iomem *pll_ctl0;
u32 pllm_lower_mask;
u32 pllm_upper_mask;
@@ -102,7 +104,11 @@ static unsigned long clk_pllclk_recalc(struct clk_hw *hw,
/* read post divider from od bits*/
postdiv = ((val & pll_data->clkod_mask) >>
pll_data->clkod_shift) + 1;
- else
+ else if (pll_data->pllod) {
+ postdiv = readl(pll_data->pllod);
+ postdiv = ((postdiv & pll_data->clkod_mask) >>
+ pll_data->clkod_shift) + 1;
+ } else
postdiv = pll_data->postdiv;
rate /= (prediv + 1);
@@ -172,12 +178,21 @@ static void __init _of_pll_clk_init(struct device_node *node, bool pllctrl)
/* assume the PLL has output divider register bits */
pll_data->clkod_mask = CLKOD_MASK;
pll_data->clkod_shift = CLKOD_SHIFT;
+
+ /*
+ * Check if there is an post-divider register. If not
+ * assume od bits are part of control register.
+ */
+ i = of_property_match_string(node, "reg-names",
+ "post-divider");
+ pll_data->pllod = of_iomap(node, i);
}
i = of_property_match_string(node, "reg-names", "control");
pll_data->pll_ctl0 = of_iomap(node, i);
if (!pll_data->pll_ctl0) {
pr_err("%s: ioremap failed\n", __func__);
+ iounmap(pll_data->pllod);
goto out;
}
@@ -193,6 +208,7 @@ static void __init _of_pll_clk_init(struct device_node *node, bool pllctrl)
pll_data->pllm = of_iomap(node, i);
if (!pll_data->pllm) {
iounmap(pll_data->pll_ctl0);
+ iounmap(pll_data->pllod);
goto out;
}
}
--
1.9.1
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