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authorSekhar Nori <nsekhar@ti.com>2009-11-16 17:21:33 +0530
committerKevin Hilman <khilman@deeprootsystems.com>2010-02-04 13:29:33 -0800
commit9a219a9ecf49ab156df4c18267ade4d468d9930e (patch)
treec71e664117603bbdf4eef09f1bb15fddccb86de4 /arch/arm
parentd2de05827cce9438dfc61d5a4cf13b6ca82ebdee (diff)
downloadblackbird-obmc-linux-9a219a9ecf49ab156df4c18267ade4d468d9930e.tar.gz
blackbird-obmc-linux-9a219a9ecf49ab156df4c18267ade4d468d9930e.zip
davinci: move PLL wait time values to clock.h
As suspend support is added, the code supporting the suspend operation needs to bypass PLLs and needs to access the same wait time values as the PLL code in clock.c. To facilitate this, move the PLL wait times to clock.h where they can be accessed by suspend code. Signed-off-by: Sekhar Nori <nsekhar@ti.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Diffstat (limited to 'arch/arm')
-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 baece65cb9c0..0fa68c558320 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 c92d77a3008d..eca4d9972225 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;
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