9 files changed, 114 insertions, 0 deletions

diff --git a/sys/amd64/amd64/tsc.c b/sys/amd64/amd64/tsc.c
index c65974141b01..4d393b041365 100644
--- a/sys/amd64/amd64/tsc.c
+++ b/sys/amd64/amd64/tsc.c
@@ -691,6 +691,28 @@ set_timer_freq(u_int freq, int intr_freq)
 }
 
 /*
+ * i8254_restore is called from apm_default_resume() to reload
+ * the countdown register.
+ * this should not be necessary but there are broken laptops that
+ * do not restore the countdown register on resume.
+ * when it happnes, it messes up the hardclock interval and system clock,
+ * which leads to the infamous "calcru: negative time" problem.
+ */
+void
+i8254_restore(void)
+{
+	u_long ef;
+
+	ef = read_eflags();
+	disable_intr();
+	outb(TIMER_MODE, TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT);
+	outb(TIMER_CNTR0, timer0_max_count & 0xff);
+	outb(TIMER_CNTR0, timer0_max_count >> 8);
+	CLOCK_UNLOCK();
+	write_eflags(ef);
+}
+
+/*
  * Initialize 8254 timer 0 early so that it can be used in DELAY().
  * XXX initialization of other timers is unintentionally left blank.
  */
diff --git a/sys/amd64/include/clock.h b/sys/amd64/include/clock.h
index f5c654a6a64f..8d0e2d3ef20e 100644
--- a/sys/amd64/include/clock.h
+++ b/sys/amd64/include/clock.h
@@ -44,6 +44,7 @@ int	acquire_timer1 __P((int mode));
 int	release_timer1 __P((void));
 #endif
 int	sysbeep __P((int pitch, int period));
+void	i8254_restore __P((void));
 
 #endif /* KERNEL */
 
diff --git a/sys/amd64/isa/clock.c b/sys/amd64/isa/clock.c
index c65974141b01..4d393b041365 100644
--- a/sys/amd64/isa/clock.c
+++ b/sys/amd64/isa/clock.c
@@ -691,6 +691,28 @@ set_timer_freq(u_int freq, int intr_freq)
 }
 
 /*
+ * i8254_restore is called from apm_default_resume() to reload
+ * the countdown register.
+ * this should not be necessary but there are broken laptops that
+ * do not restore the countdown register on resume.
+ * when it happnes, it messes up the hardclock interval and system clock,
+ * which leads to the infamous "calcru: negative time" problem.
+ */
+void
+i8254_restore(void)
+{
+	u_long ef;
+
+	ef = read_eflags();
+	disable_intr();
+	outb(TIMER_MODE, TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT);
+	outb(TIMER_CNTR0, timer0_max_count & 0xff);
+	outb(TIMER_CNTR0, timer0_max_count >> 8);
+	CLOCK_UNLOCK();
+	write_eflags(ef);
+}
+
+/*
  * Initialize 8254 timer 0 early so that it can be used in DELAY().
  * XXX initialization of other timers is unintentionally left blank.
  */
diff --git a/sys/i386/apm/apm.c b/sys/i386/apm/apm.c
index 96860f6a9d67..9630f02e5281 100644
--- a/sys/i386/apm/apm.c
+++ b/sys/i386/apm/apm.c
@@ -404,6 +404,7 @@ apm_default_resume(void *arg)
 
 	/* modified for adjkerntz */
 	pl = splsoftclock();
+	i8254_restore();		/* restore timer_freq and hz */
 	inittodr(0);			/* adjust time to RTC */
 	microtime(&resume_time);
 	getmicrotime(&tmp_time);
diff --git a/sys/i386/bios/apm.c b/sys/i386/bios/apm.c
index 96860f6a9d67..9630f02e5281 100644
--- a/sys/i386/bios/apm.c
+++ b/sys/i386/bios/apm.c
@@ -404,6 +404,7 @@ apm_default_resume(void *arg)
 
 	/* modified for adjkerntz */
 	pl = splsoftclock();
+	i8254_restore();		/* restore timer_freq and hz */
 	inittodr(0);			/* adjust time to RTC */
 	microtime(&resume_time);
 	getmicrotime(&tmp_time);
diff --git a/sys/i386/i386/tsc.c b/sys/i386/i386/tsc.c
index c65974141b01..4d393b041365 100644
--- a/sys/i386/i386/tsc.c
+++ b/sys/i386/i386/tsc.c
@@ -691,6 +691,28 @@ set_timer_freq(u_int freq, int intr_freq)
 }
 
 /*
+ * i8254_restore is called from apm_default_resume() to reload
+ * the countdown register.
+ * this should not be necessary but there are broken laptops that
+ * do not restore the countdown register on resume.
+ * when it happnes, it messes up the hardclock interval and system clock,
+ * which leads to the infamous "calcru: negative time" problem.
+ */
+void
+i8254_restore(void)
+{
+	u_long ef;
+
+	ef = read_eflags();
+	disable_intr();
+	outb(TIMER_MODE, TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT);
+	outb(TIMER_CNTR0, timer0_max_count & 0xff);
+	outb(TIMER_CNTR0, timer0_max_count >> 8);
+	CLOCK_UNLOCK();
+	write_eflags(ef);
+}
+
+/*
  * Initialize 8254 timer 0 early so that it can be used in DELAY().
  * XXX initialization of other timers is unintentionally left blank.
  */
diff --git a/sys/i386/include/clock.h b/sys/i386/include/clock.h
index f5c654a6a64f..8d0e2d3ef20e 100644
--- a/sys/i386/include/clock.h
+++ b/sys/i386/include/clock.h
@@ -44,6 +44,7 @@ int	acquire_timer1 __P((int mode));
 int	release_timer1 __P((void));
 #endif
 int	sysbeep __P((int pitch, int period));
+void	i8254_restore __P((void));
 
 #endif /* KERNEL */
 
diff --git a/sys/i386/isa/clock.c b/sys/i386/isa/clock.c
index c65974141b01..4d393b041365 100644
--- a/sys/i386/isa/clock.c
+++ b/sys/i386/isa/clock.c
@@ -691,6 +691,28 @@ set_timer_freq(u_int freq, int intr_freq)
 }
 
 /*
+ * i8254_restore is called from apm_default_resume() to reload
+ * the countdown register.
+ * this should not be necessary but there are broken laptops that
+ * do not restore the countdown register on resume.
+ * when it happnes, it messes up the hardclock interval and system clock,
+ * which leads to the infamous "calcru: negative time" problem.
+ */
+void
+i8254_restore(void)
+{
+	u_long ef;
+
+	ef = read_eflags();
+	disable_intr();
+	outb(TIMER_MODE, TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT);
+	outb(TIMER_CNTR0, timer0_max_count & 0xff);
+	outb(TIMER_CNTR0, timer0_max_count >> 8);
+	CLOCK_UNLOCK();
+	write_eflags(ef);
+}
+
+/*
  * Initialize 8254 timer 0 early so that it can be used in DELAY().
  * XXX initialization of other timers is unintentionally left blank.
  */
diff --git a/sys/isa/atrtc.c b/sys/isa/atrtc.c
index c65974141b01..4d393b041365 100644
--- a/sys/isa/atrtc.c
+++ b/sys/isa/atrtc.c
@@ -691,6 +691,28 @@ set_timer_freq(u_int freq, int intr_freq)
 }
 
 /*
+ * i8254_restore is called from apm_default_resume() to reload
+ * the countdown register.
+ * this should not be necessary but there are broken laptops that
+ * do not restore the countdown register on resume.
+ * when it happnes, it messes up the hardclock interval and system clock,
+ * which leads to the infamous "calcru: negative time" problem.
+ */
+void
+i8254_restore(void)
+{
+	u_long ef;
+
+	ef = read_eflags();
+	disable_intr();
+	outb(TIMER_MODE, TIMER_SEL0 | TIMER_RATEGEN | TIMER_16BIT);
+	outb(TIMER_CNTR0, timer0_max_count & 0xff);
+	outb(TIMER_CNTR0, timer0_max_count >> 8);
+	CLOCK_UNLOCK();
+	write_eflags(ef);
+}
+
+/*
  * Initialize 8254 timer 0 early so that it can be used in DELAY().
  * XXX initialization of other timers is unintentionally left blank.
  */