Use ip27 hub real time counter for sched_clock source. This implementation
will give high resolution cputime accounting.
Signed-off-by: Deng-Cheng Zhu <dengcheng.zhu@xxxxxxxxxx>
---
arch/mips/sgi-ip27/ip27-timer.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/arch/mips/sgi-ip27/ip27-timer.c b/arch/mips/sgi-ip27/ip27-timer.c
index 1d97eab..a6d10f6 100644
--- a/arch/mips/sgi-ip27/ip27-timer.c
+++ b/arch/mips/sgi-ip27/ip27-timer.c
@@ -7,6 +7,7 @@
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
+#include <linux/sched_clock.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/param.h>
@@ -159,11 +160,18 @@ struct clocksource hub_rt_clocksource = {
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
+static u64 notrace hub_rt_read_sched_clock(void)
+{
+ return REMOTE_HUB_L(cputonasid(0), PI_RT_COUNT);
+}
+
static void __init hub_rt_clocksource_init(void)
{
struct clocksource *cs = &hub_rt_clocksource;
clocksource_register_hz(cs, CYCLES_PER_SEC);
+
+ sched_clock_register(hub_rt_read_sched_clock, 52, CYCLES_PER_SEC);
}
void __init plat_time_init(void)
--
2.3.2
