aboutsummaryrefslogtreecommitdiff
path: root/hw/i8254.c
diff options
context:
space:
mode:
authoraliguori <aliguori@c046a42c-6fe2-441c-8c8c-71466251a162>2008-12-17 23:28:44 +0000
committeraliguori <aliguori@c046a42c-6fe2-441c-8c8c-71466251a162>2008-12-17 23:28:44 +0000
commit16b29ae1807b024bd5052301550f5d47dae958a2 (patch)
treeeeeb5072d4548b91f2111f3127737a374d89cab2 /hw/i8254.c
parent0bacd1300dbcd7f56bdbf1ca73438b6a68c31b8f (diff)
downloadqemu-16b29ae1807b024bd5052301550f5d47dae958a2.zip
qemu-16b29ae1807b024bd5052301550f5d47dae958a2.tar.gz
qemu-16b29ae1807b024bd5052301550f5d47dae958a2.tar.bz2
Add HPET emulation to qemu (Beth Kon)
This patch adds HPET emulation. It can be disabled with -disable-hpet. An hpet provides a more finely granular clocksource than otherwise available on PC. This means that latency-dependent applications (e.g. multimedia) will generally be smoother when using the HPET. Signed-off-by: Beth Kon <eak@us.ibm.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6081 c046a42c-6fe2-441c-8c8c-71466251a162
Diffstat (limited to 'hw/i8254.c')
-rw-r--r--hw/i8254.c21
1 files changed, 21 insertions, 0 deletions
diff --git a/hw/i8254.c b/hw/i8254.c
index 4813b03..1625787 100644
--- a/hw/i8254.c
+++ b/hw/i8254.c
@@ -463,6 +463,27 @@ static void pit_reset(void *opaque)
}
}
+/* When HPET is operating in legacy mode, i8254 timer0 is disabled */
+void hpet_pit_disable(void) {
+ PITChannelState *s;
+ s = &pit_state.channels[0];
+ qemu_del_timer(s->irq_timer);
+}
+
+/* When HPET is reset or leaving legacy mode, it must reenable i8254
+ * timer 0
+ */
+
+void hpet_pit_enable(void)
+{
+ PITState *pit = &pit_state;
+ PITChannelState *s;
+ s = &pit->channels[0];
+ s->mode = 3;
+ s->gate = 1;
+ pit_load_count(s, 0);
+}
+
PITState *pit_init(int base, qemu_irq irq)
{
PITState *pit = &pit_state;