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-rw-r--r--arch/arm/mach-davinci/clock.c15
-rw-r--r--arch/arm/mach-davinci/clock.h15
2 files changed, 18 insertions, 12 deletions
diff --git a/arch/arm/mach-davinci/clock.c b/arch/arm/mach-davinci/clock.c
index baece65cb9c..0fa68c55832 100644
--- a/arch/arm/mach-davinci/clock.c
+++ b/arch/arm/mach-davinci/clock.c
@@ -376,7 +376,7 @@ int davinci_set_pllrate(struct pll_data *pll, unsigned int prediv,
locktime = ((2000 * prediv) / 100);
prediv = (prediv - 1) | PLLDIV_EN;
} else {
- locktime = 20;
+ locktime = PLL_LOCK_TIME;
}
if (postdiv)
postdiv = (postdiv - 1) | PLLDIV_EN;
@@ -389,12 +389,7 @@ int davinci_set_pllrate(struct pll_data *pll, unsigned int prediv,
ctrl &= ~(PLLCTL_PLLENSRC | PLLCTL_PLLEN);
__raw_writel(ctrl, pll->base + PLLCTL);
- /*
- * Wait for 4 OSCIN/CLKIN cycles to ensure that the PLLC has switched
- * to bypass mode. Delay of 1us ensures we are good for all > 4MHz
- * OSCIN/CLKIN inputs. Typically the input is ~25MHz.
- */
- udelay(1);
+ udelay(PLL_BYPASS_TIME);
/* Reset and enable PLL */
ctrl &= ~(PLLCTL_PLLRST | PLLCTL_PLLDIS);
@@ -408,11 +403,7 @@ int davinci_set_pllrate(struct pll_data *pll, unsigned int prediv,
if (pll->flags & PLL_HAS_POSTDIV)
__raw_writel(postdiv, pll->base + POSTDIV);
- /*
- * Wait for PLL to reset properly, OMAP-L138 datasheet says
- * 'min' time = 125ns
- */
- udelay(1);
+ udelay(PLL_RESET_TIME);
/* Bring PLL out of reset */
ctrl |= PLLCTL_PLLRST;
diff --git a/arch/arm/mach-davinci/clock.h b/arch/arm/mach-davinci/clock.h
index c92d77a3008..eca4d997222 100644
--- a/arch/arm/mach-davinci/clock.h
+++ b/arch/arm/mach-davinci/clock.h
@@ -53,6 +53,21 @@
#define PLLDIV_EN BIT(15)
#define PLLDIV_RATIO_MASK 0x1f
+/*
+ * OMAP-L138 system reference guide recommends a wait for 4 OSCIN/CLKIN
+ * cycles to ensure that the PLLC has switched to bypass mode. Delay of 1us
+ * ensures we are good for all > 4MHz OSCIN/CLKIN inputs. Typically the input
+ * is ~25MHz. Units are micro seconds.
+ */
+#define PLL_BYPASS_TIME 1
+/* From OMAP-L138 datasheet table 6-4. Units are micro seconds */
+#define PLL_RESET_TIME 1
+/*
+ * From OMAP-L138 datasheet table 6-4; assuming prediv = 1, sqrt(pllm) = 4
+ * Units are micro seconds.
+ */
+#define PLL_LOCK_TIME 20
+
struct pll_data {
u32 phys_base;
void __iomem *base;