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authorJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-11 10:41:07 +0300
committerJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-13 08:17:18 +0300
commite09b41010ba33a20a87472ee821fa407a5b8da36 (patch)
treed10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/drivers/clocksource/i8253.c
parentf93b97fd65072de626c074dbe099a1fff05ce060 (diff)
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page. During the rebasing, the following patch collided: Force tick interrupt and get rid of softirq magic(I70131fb85). Collisions have been removed because its logic was found on the source already. Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769 Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/drivers/clocksource/i8253.c')
-rw-r--r--kernel/drivers/clocksource/i8253.c77
1 files changed, 38 insertions, 39 deletions
diff --git a/kernel/drivers/clocksource/i8253.c b/kernel/drivers/clocksource/i8253.c
index 14ee3efcc..0efd36e48 100644
--- a/kernel/drivers/clocksource/i8253.c
+++ b/kernel/drivers/clocksource/i8253.c
@@ -100,44 +100,40 @@ int __init clocksource_i8253_init(void)
#endif
#ifdef CONFIG_CLKEVT_I8253
-/*
- * Initialize the PIT timer.
- *
- * This is also called after resume to bring the PIT into operation again.
- */
-static void init_pit_timer(enum clock_event_mode mode,
- struct clock_event_device *evt)
+static int pit_shutdown(struct clock_event_device *evt)
{
+ if (!clockevent_state_oneshot(evt) && !clockevent_state_periodic(evt))
+ return 0;
+
raw_spin_lock(&i8253_lock);
- switch (mode) {
- case CLOCK_EVT_MODE_PERIODIC:
- /* binary, mode 2, LSB/MSB, ch 0 */
- outb_p(0x34, PIT_MODE);
- outb_p(PIT_LATCH & 0xff , PIT_CH0); /* LSB */
- outb_p(PIT_LATCH >> 8 , PIT_CH0); /* MSB */
- break;
-
- case CLOCK_EVT_MODE_SHUTDOWN:
- case CLOCK_EVT_MODE_UNUSED:
- if (evt->mode == CLOCK_EVT_MODE_PERIODIC ||
- evt->mode == CLOCK_EVT_MODE_ONESHOT) {
- outb_p(0x30, PIT_MODE);
- outb_p(0, PIT_CH0);
- outb_p(0, PIT_CH0);
- }
- break;
-
- case CLOCK_EVT_MODE_ONESHOT:
- /* One shot setup */
- outb_p(0x38, PIT_MODE);
- break;
-
- case CLOCK_EVT_MODE_RESUME:
- /* Nothing to do here */
- break;
- }
+ outb_p(0x30, PIT_MODE);
+ outb_p(0, PIT_CH0);
+ outb_p(0, PIT_CH0);
+
+ raw_spin_unlock(&i8253_lock);
+ return 0;
+}
+
+static int pit_set_oneshot(struct clock_event_device *evt)
+{
+ raw_spin_lock(&i8253_lock);
+ outb_p(0x38, PIT_MODE);
+ raw_spin_unlock(&i8253_lock);
+ return 0;
+}
+
+static int pit_set_periodic(struct clock_event_device *evt)
+{
+ raw_spin_lock(&i8253_lock);
+
+ /* binary, mode 2, LSB/MSB, ch 0 */
+ outb_p(0x34, PIT_MODE);
+ outb_p(PIT_LATCH & 0xff, PIT_CH0); /* LSB */
+ outb_p(PIT_LATCH >> 8, PIT_CH0); /* MSB */
+
raw_spin_unlock(&i8253_lock);
+ return 0;
}
/*
@@ -160,10 +156,11 @@ static int pit_next_event(unsigned long delta, struct clock_event_device *evt)
* it can be solely used for the global tick.
*/
struct clock_event_device i8253_clockevent = {
- .name = "pit",
- .features = CLOCK_EVT_FEAT_PERIODIC,
- .set_mode = init_pit_timer,
- .set_next_event = pit_next_event,
+ .name = "pit",
+ .features = CLOCK_EVT_FEAT_PERIODIC,
+ .set_state_shutdown = pit_shutdown,
+ .set_state_periodic = pit_set_periodic,
+ .set_next_event = pit_next_event,
};
/*
@@ -172,8 +169,10 @@ struct clock_event_device i8253_clockevent = {
*/
void __init clockevent_i8253_init(bool oneshot)
{
- if (oneshot)
+ if (oneshot) {
i8253_clockevent.features |= CLOCK_EVT_FEAT_ONESHOT;
+ i8253_clockevent.set_state_oneshot = pit_set_oneshot;
+ }
/*
* Start pit with the boot cpu mask. x86 might make it global
* when it is used as broadcast device later.