davinci: clock: add support for setting sysclk rate

Setting sysclk rate will be useful in cases where the
sysclk is not at a fixed ratio to the PLL output but
can asynchronously be changed.

This support forms the basis of attempt to keep the AEMIF
clock constant on OMAP-L138 even as PLL0 output changes
as ARM clock is changed to save power.

This patch has been tested on OMAP-L138.

Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/arch/arm/mach-davinci/clock.h b/arch/arm/mach-davinci/clock.h
index 01e36483ac3d..11099980b58b 100644
--- a/arch/arm/mach-davinci/clock.h
+++ b/arch/arm/mach-davinci/clock.h
@@ -70,6 +70,9 @@
 #include <linux/list.h>
 #include <asm/clkdev.h>
 
+#define PLLSTAT_GOSTAT  BIT(0)
+#define PLLCMD_GOSET    BIT(0)
+
 struct pll_data {
         u32 phys_base;
         void __iomem *base;
@@ -86,6 +89,7 @@ struct clk {
         struct module           *owner;
         const char              *name;
         unsigned long           rate;
+        unsigned long           maxrate;        /* H/W supported max rate */
         u8                      usecount;
         u8                      lpsc;
         u8                      gpsc;
@@ -118,6 +122,7 @@ struct clk {
 int davinci_clk_init(struct clk_lookup *clocks);
 int davinci_set_pllrate(struct pll_data *pll, unsigned int prediv,
                                 unsigned int mult, unsigned int postdiv);
+int davinci_set_sysclk_rate(struct clk *clk, unsigned long rate);
 
 extern struct platform_device davinci_wdt_device;
 extern void davinci_watchdog_reset(struct platform_device *);