[ARM] sa1100: add clock source support
Add generic clock source support for SA11x0 platforms.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index a04f507..7425279 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -366,6 +366,7 @@
select ARCH_DISCONTIGMEM_ENABLE
select ARCH_MTD_XIP
select GENERIC_GPIO
+ select GENERIC_TIME
help
Support for StrongARM 11x0 based boards.
diff --git a/arch/arm/mach-sa1100/time.c b/arch/arm/mach-sa1100/time.c
index fdf7b01..7298435 100644
--- a/arch/arm/mach-sa1100/time.c
+++ b/arch/arm/mach-sa1100/time.c
@@ -14,6 +14,7 @@
#include <linux/irq.h>
#include <linux/timex.h>
#include <linux/signal.h>
+#include <linux/clocksource.h>
#include <asm/mach/time.h>
#include <asm/hardware.h>
@@ -35,23 +36,6 @@
return 0;
}
-/* IRQs are disabled before entering here from do_gettimeofday() */
-static unsigned long sa1100_gettimeoffset (void)
-{
- unsigned long ticks_to_match, elapsed, usec;
-
- /* Get ticks before next timer match */
- ticks_to_match = OSMR0 - OSCR;
-
- /* We need elapsed ticks since last match */
- elapsed = LATCH - ticks_to_match;
-
- /* Now convert them to usec */
- usec = (unsigned long)(elapsed * (tick_nsec / 1000))/LATCH;
-
- return usec;
-}
-
#ifdef CONFIG_NO_IDLE_HZ
static unsigned long initial_match;
static int match_posponed;
@@ -96,6 +80,20 @@
.handler = sa1100_timer_interrupt,
};
+static cycle_t sa1100_read_oscr(void)
+{
+ return OSCR;
+}
+
+static struct clocksource cksrc_sa1100_oscr = {
+ .name = "oscr",
+ .rating = 200,
+ .read = sa1100_read_oscr,
+ .mask = CLOCKSOURCE_MASK(32),
+ .shift = 20,
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
static void __init sa1100_timer_init(void)
{
unsigned long flags;
@@ -109,6 +107,11 @@
OIER = OIER_E0; /* enable match on timer 0 to cause interrupts */
OSMR0 = OSCR + LATCH; /* set initial match */
local_irq_restore(flags);
+
+ cksrc_sa1100_oscr.mult =
+ clocksource_hz2mult(CLOCK_TICK_RATE, cksrc_sa1100_oscr.shift);
+
+ clocksource_register(&cksrc_sa1100_oscr);
}
#ifdef CONFIG_NO_IDLE_HZ
@@ -182,7 +185,6 @@
.init = sa1100_timer_init,
.suspend = sa1100_timer_suspend,
.resume = sa1100_timer_resume,
- .offset = sa1100_gettimeoffset,
#ifdef CONFIG_NO_IDLE_HZ
.dyn_tick = &sa1100_dyn_tick,
#endif