x86: hpet: provide separate functions to stop and start the counter

By splitting up existing hpet_start_counter function.
Signed-off-by: NAndreas Herrmann <andreas.herrmann3@amd.com>
Cc: Mark Hounschell <markh@compro.net>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

arch/x86/kernel/hpet.c

@@ -231,27 +231,37 @@ static struct clock_event_device hpet_clockevent = {
 	.rating		= 50,
 };
 
-static void hpet_start_counter(void)
+static void hpet_stop_counter(void)
 {
 	unsigned long cfg = hpet_readl(HPET_CFG);
-
 	cfg &= ~HPET_CFG_ENABLE;
 	hpet_writel(cfg, HPET_CFG);
 	hpet_writel(0, HPET_COUNTER);
 	hpet_writel(0, HPET_COUNTER + 4);
+}
+
+static void hpet_start_counter(void)
+{
+	unsigned long cfg = hpet_readl(HPET_CFG);
 	cfg |= HPET_CFG_ENABLE;
 	hpet_writel(cfg, HPET_CFG);
 }
 
+static void hpet_restart_counter(void)
+{
+	hpet_stop_counter();
+	hpet_start_counter();
+}
+
 static void hpet_resume_device(void)
 {
 	force_hpet_resume();
 }
 
-static void hpet_restart_counter(void)
+static void hpet_resume_counter(void)
 {
 	hpet_resume_device();
-	hpet_start_counter();
+	hpet_restart_counter();
 }
 
 static void hpet_enable_legacy_int(void)
@@ -738,7 +748,7 @@ static struct clocksource clocksource_hpet = {
 	.mask		= HPET_MASK,
 	.shift		= HPET_SHIFT,
 	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
-	.resume		= hpet_restart_counter,
+	.resume		= hpet_resume_counter,
 #ifdef CONFIG_X86_64
 	.vread		= vread_hpet,
 #endif
@@ -750,7 +760,7 @@ static int hpet_clocksource_register(void)
 	cycle_t t1;
 
 	/* Start the counter */
-	hpet_start_counter();
+	hpet_restart_counter();
 
 	/* Verify whether hpet counter works */
 	t1 = read_hpet();