From 6198c499368711fa914adb5f6bec46d171ad203c Mon Sep 17 00:00:00 2001
From: Sepherosa Ziehau <sephe@dragonflybsd.org>
Date: Sat, 2 May 2009 16:26:22 +0800
Subject: [PATCH] lapic timer: Improve lapic timer testing

- Add lapic_timer_oneshot_intr_enable(), which set lapic timer into
  one shot mode and enable lapic timer interrupt.  It is called
  during per-cpu systimers initialization.
- Add lapic_timer_oneshot_quick(), which only set lapic timer's ICR
---
 sys/platform/pc32/apic/mpapic.c | 47 ++++++++++++++++++---------------
 sys/platform/pc32/isa/clock.c   | 11 ++++++--
 2 files changed, 34 insertions(+), 24 deletions(-)

diff --git a/sys/platform/pc32/apic/mpapic.c b/sys/platform/pc32/apic/mpapic.c
index 3bc525a41b..773b14c61d 100644
--- a/sys/platform/pc32/apic/mpapic.c
+++ b/sys/platform/pc32/apic/mpapic.c
@@ -46,7 +46,8 @@ static void	lapic_timer_calibrate(void);
 static void	lapic_timer_set_divisor(int);
 void		lapic_timer_process(void);
 void		lapic_timer_process_frame(struct intrframe *);
-void		lapic_timer_intr_reload(sysclock_t);
+void		lapic_timer_intr_test(void);
+void		lapic_timer_oneshot_intr_enable(void);
 
 int		lapic_timer_test;
 TUNABLE_INT("hw.lapic_timer_test", &lapic_timer_test);
@@ -214,6 +215,12 @@ lapic_timer_oneshot(u_int count)
 	lapic.icr_timer = count;
 }
 
+static void
+lapic_timer_oneshot_quick(u_int count)
+{
+	lapic.icr_timer = count;
+}
+
 static void
 lapic_timer_calibrate(void)
 {
@@ -243,7 +250,7 @@ lapic_timer_process(void)
 {
 	struct globaldata *gd = mycpu;
 
-	gd->gd_timer_running = 1;
+	gd->gd_timer_running = 0;
 
 	if (lapic_timer_test)
 		kprintf("%d proc\n", gd->gd_cpuid);
@@ -254,38 +261,34 @@ lapic_timer_process_frame(struct intrframe *frame)
 {
 	struct globaldata *gd = mycpu;
 
-	gd->gd_timer_running = 1;
+	gd->gd_timer_running = 0;
 
 	if (lapic_timer_test)
 		kprintf("%d proc frame\n", gd->gd_cpuid);
 }
 
 void
-lapic_timer_intr_reload(sysclock_t reload)
+lapic_timer_intr_test(void)
 {
 	struct globaldata *gd = mycpu;
 
-	if (lapic_timer_test) {
-		if (gd->gd_timer_running == 2) {
-			return;
-		} else if (gd->gd_timer_running == 1) {
-			gd->gd_timer_running = 2;
-			KKASSERT(lapic_timer_freq != 0);
-			lapic_timer_oneshot(lapic_timer_freq);
-		} else if (gd->gd_timer_running == 0) {
-			uint32_t timer;
-
-			timer = lapic.lvt_timer;
-			timer &= ~APIC_LVTT_MASKED;
-			lapic.lvt_timer = timer;
-
-			gd->gd_timer_running = 2;
-			KKASSERT(lapic_timer_freq != 0);
-			lapic_timer_oneshot(lapic_timer_freq);
-		}
+	if (!gd->gd_timer_running) {
+		gd->gd_timer_running = 1;
+		KKASSERT(lapic_timer_freq != 0);
+		lapic_timer_oneshot_quick(lapic_timer_freq);
 	}
 }
 
+void
+lapic_timer_oneshot_intr_enable(void)
+{
+	uint32_t timer;
+
+	timer = lapic.lvt_timer;
+	timer &= ~(APIC_LVTT_MASKED | APIC_LVTT_PERIODIC);
+	lapic.lvt_timer = timer;
+}
+
 
 /*
  * dump contents of local APIC registers
diff --git a/sys/platform/pc32/isa/clock.c b/sys/platform/pc32/isa/clock.c
index 65c3a2ef89..4c95906a11 100644
--- a/sys/platform/pc32/isa/clock.c
+++ b/sys/platform/pc32/isa/clock.c
@@ -362,7 +362,9 @@ i8254_intr_reload(sysclock_t reload)
 }
 
 #ifdef SMP
-extern void	lapic_timer_intr_reload(sysclock_t);
+extern int	lapic_timer_test;
+extern void	lapic_timer_oneshot_intr_enable(void);
+extern void	lapic_timer_intr_test(void);
 #endif
 
 void
@@ -370,13 +372,18 @@ cputimer_intr_reload(sysclock_t reload)
 {
 	i8254_intr_reload(reload);
 #ifdef SMP
-	lapic_timer_intr_reload(reload);
+	if (__predict_false(lapic_timer_test))
+		lapic_timer_intr_test();
 #endif
 }
 
 void
 cputimer_intr_enable(void)
 {
+#ifdef SMP
+	if (lapic_timer_test)
+		lapic_timer_oneshot_intr_enable();
+#endif
 }
 
 /*
-- 
2.41.0