1 files changed, 50 insertions, 0 deletions

diff --git a/arch/arm/plat-omap/common.c b/arch/arm/plat-omap/common.c
index 57b7b93674a4..fecd3d625995 100644
--- a/arch/arm/plat-omap/common.c
+++ b/arch/arm/plat-omap/common.c
@@ -156,3 +156,53 @@ static int __init omap_add_serial_console(void)
         return add_preferred_console("ttyS", line, opt);
 }
 console_initcall(omap_add_serial_console);
+
+
+/*
+ * 32KHz clocksource ... always available, on pretty most chips except
+ * OMAP 730 and 1510.  Other timers could be used as clocksources, with
+ * higher resolution in free-running counter modes (e.g. 12 MHz xtal),
+ * but systems won't necessarily want to spend resources that way.
+ */
+
+#if defined(CONFIG_ARCH_OMAP16XX)
+#define TIMER_32K_SYNCHRONIZED          0xfffbc410
+#elif defined(CONFIG_ARCH_OMAP24XX)
+#define TIMER_32K_SYNCHRONIZED          0x48004010
+#endif
+
+#ifdef  TIMER_32K_SYNCHRONIZED
+
+#include <linux/clocksource.h>
+
+static cycle_t omap_32k_read(void)
+{
+        return omap_readl(TIMER_32K_SYNCHRONIZED);
+}
+
+static struct clocksource clocksource_32k = {
+        .name           = "32k_counter",
+        .rating         = 250,
+        .read           = omap_32k_read,
+        .mask           = CLOCKSOURCE_MASK(32),
+        .shift          = 10,
+        .flags          = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static int __init omap_init_clocksource_32k(void)
+{
+        static char err[] __initdata = KERN_ERR
+                        "%s: can't register clocksource!\n";
+
+        if (cpu_is_omap16xx() || cpu_is_omap24xx()) {
+                clocksource_32k.mult = clocksource_hz2mult(32768,
+                                            clocksource_32k.shift);
+
+                if (clocksource_register(&clocksource_32k))
+                        printk(err, clocksource_32k.name);
+        }
+        return 0;
+}
+arch_initcall(omap_init_clocksource_32k);
+
+#endif  /* TIMER_32K_SYNCHRONIZED */