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authorPaul Walmsley <paul@pwsan.com>2009-07-25 05:44:03 +0400
committerpaul <paul@twilight.(none)>2009-07-25 06:10:35 +0400
commit72350b29a4c0debfc27c2edbeed9b4ff3f935dd4 (patch)
tree0c4637987fdbe97bfbdab7e00031283af47aadc1 /arch/arm/mach-omap2/prcm.c
parentdf56556e571234cf26072cd58c01ac3520986b44 (diff)
downloadlinux-72350b29a4c0debfc27c2edbeed9b4ff3f935dd4.tar.xz
OMAP2/3 clock: split, rename omap2_wait_clock_ready()
Some OMAP2/3 hardware modules have CM_IDLEST attributes that are not handled by the current omap2_wait_clock_ready() code. In preparation for patches that fix the unusual devices, rename the function omap2_wait_clock_ready() to omap2_wait_module_ready() and split it into three parts: 1. A clkops-specific companion clock return function (by default, omap2_clk_dflt_find_companion()) 2. A clkops-specific CM_IDLEST register address and bit shift return function (by default, omap2_clk_dflt_find_idlest()) 3. Code to wait for the CM to indicate that the module is ready (omap2_cm_wait_idlest()) Clocks can now specify their own custom find_companion() and find_idlest() functions; used in subsequent patches. Signed-off-by: Paul Walmsley <paul@pwsan.com>
Diffstat (limited to 'arch/arm/mach-omap2/prcm.c')
-rw-r--r--arch/arm/mach-omap2/prcm.c43
1 files changed, 43 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/prcm.c b/arch/arm/mach-omap2/prcm.c
index f945156d5585..ced555a4cd1a 100644
--- a/arch/arm/mach-omap2/prcm.c
+++ b/arch/arm/mach-omap2/prcm.c
@@ -17,6 +17,7 @@
#include <linux/init.h>
#include <linux/clk.h>
#include <linux/io.h>
+#include <linux/delay.h>
#include <mach/common.h>
#include <mach/prcm.h>
@@ -28,6 +29,8 @@
static void __iomem *prm_base;
static void __iomem *cm_base;
+#define MAX_MODULE_ENABLE_WAIT 100000
+
u32 omap_prcm_get_reset_sources(void)
{
/* XXX This presumably needs modification for 34XX */
@@ -120,6 +123,46 @@ u32 cm_rmw_mod_reg_bits(u32 mask, u32 bits, s16 module, s16 idx)
}
EXPORT_SYMBOL(cm_rmw_mod_reg_bits);
+/**
+ * omap2_cm_wait_idlest - wait for IDLEST bit to indicate module readiness
+ * @reg: physical address of module IDLEST register
+ * @mask: value to mask against to determine if the module is active
+ * @name: name of the clock (for printk)
+ *
+ * Returns 1 if the module indicated readiness in time, or 0 if it
+ * failed to enable in roughly MAX_MODULE_ENABLE_WAIT microseconds.
+ */
+int omap2_cm_wait_idlest(void __iomem *reg, u32 mask, const char *name)
+{
+ int i = 0;
+ int ena = 0;
+
+ /*
+ * 24xx uses 0 to indicate not ready, and 1 to indicate ready.
+ * 34xx reverses this, just to keep us on our toes
+ */
+ if (cpu_is_omap24xx())
+ ena = mask;
+ else if (cpu_is_omap34xx())
+ ena = 0;
+ else
+ BUG();
+
+ /* Wait for lock */
+ while (((__raw_readl(reg) & mask) != ena) &&
+ (i++ < MAX_MODULE_ENABLE_WAIT))
+ udelay(1);
+
+ if (i < MAX_MODULE_ENABLE_WAIT)
+ pr_debug("cm: Module associated with clock %s ready after %d "
+ "loops\n", name, i);
+ else
+ pr_err("cm: Module associated with clock %s didn't enable in "
+ "%d tries\n", name, MAX_MODULE_ENABLE_WAIT);
+
+ return (i < MAX_MODULE_ENABLE_WAIT) ? 1 : 0;
+};
+
void __init omap2_set_globals_prcm(struct omap_globals *omap2_globals)
{
prm_base = omap2_globals->prm;