Dynamically choose the quality of the ACPI timer depending on whether

the fast or safe/slow method is in use.  Fast remains at 1000, slow is
now at 850 (always preferred to TSC).  Since the HPET has proven slower
than ACPI-fast on some systems, drop its quality to 900.  In the future,
it is hoped that HPET performance will improve as it is the main
timer Intel supports.  HPET may move back to 2000 in -current once RELENG_7
is branched to ensure that it gets tested.

Approved by:	re

2 files changed, 4 insertions, 2 deletions

diff --git a/sys/dev/acpica/acpi_hpet.c b/sys/dev/acpica/acpi_hpet.c
index f0efff3..56a9c9c 100644
--- a/sys/dev/acpica/acpi_hpet.c
+++ b/sys/dev/acpica/acpi_hpet.c
@@ -70,7 +70,7 @@ struct timecounter hpet_timecounter = {
 	.tc_get_timecount =	hpet_get_timecount,
 	.tc_counter_mask =	~0u,
 	.tc_name =		"HPET",
-	.tc_quality =		2000,
+	.tc_quality =		900,
 };
 
 static u_int
diff --git a/sys/dev/acpica/acpi_timer.c b/sys/dev/acpica/acpi_timer.c
index f83978e..73bd5ed 100644
--- a/sys/dev/acpica/acpi_timer.c
+++ b/sys/dev/acpica/acpi_timer.c
@@ -96,7 +96,7 @@ static struct timecounter acpi_timer_timecounter = {
 	0,				/* no default counter_mask */
 	0,				/* no default frequency */
 	"ACPI",				/* name */
-	1000				/* quality */
+	-1				/* quality (chosen later) */
 };
 
 static u_int
@@ -185,9 +185,11 @@ acpi_timer_probe(device_t dev)
     if (j == 10) {
 	acpi_timer_timecounter.tc_name = "ACPI-fast";
 	acpi_timer_timecounter.tc_get_timecount = acpi_timer_get_timecount;
+	acpi_timer_timecounter.tc_quality = 1000;
     } else {
 	acpi_timer_timecounter.tc_name = "ACPI-safe";
 	acpi_timer_timecounter.tc_get_timecount = acpi_timer_get_timecount_safe;
+	acpi_timer_timecounter.tc_quality = 850;
     }
     tc_init(&acpi_timer_timecounter);