3 files changed, 9 insertions, 3 deletions
diff --git a/kernel/drivers/acpi.c b/kernel/drivers/acpi.c
index 15007d7..4c7a1a8 100644
--- a/kernel/drivers/acpi.c
+++ b/kernel/drivers/acpi.c
@@ -78,11 +78,12 @@ void hpet_install(int period)
 {
 	if (hpet && hpet->legacy_replacement && hpet->comparator_count > 0) {
 		struct hpet_registers *r = (struct hpet_registers *)hpet->address.phys;
-		printf("HPET tick period: %dns\n", r->tick_period / 1000000);
+		printf("HPET tick period: %dns\n", HPET_MAX_PERIOD / r->tick_period);
 		if ((r->timer0 & hpet_periodic_support) == hpet_periodic_support) {
 			r->config |= hpet_enable;
 			r->config |= hpet_legacy_replacement;
 			r->timer0 |= hpet_periodic | hpet_set_accumulator | hpet_enable_timer;
+			assert(r->tick_period + period < HPET_MAX_PERIOD);
 			r->timer_comparator0 = r->tick_period + period;
 			r->timer_comparator0 = period;
 		}
diff --git a/kernel/drivers/timer.c b/kernel/drivers/timer.c
index 788e286..8029a2a 100644
--- a/kernel/drivers/timer.c
+++ b/kernel/drivers/timer.c
@@ -22,7 +22,10 @@ u32 timer_get()
 
 void timer_handler()
 {
-	timer_ticks++;
+	if (timer_ticks >= U32_MAX)
+		timer_ticks = 0;
+	else
+		timer_ticks++;
 }
 
 // "Delay" function with CPU sleep
diff --git a/kernel/inc/acpi.h b/kernel/inc/acpi.h
index 3a25098..6cebf9b 100644
--- a/kernel/inc/acpi.h
+++ b/kernel/inc/acpi.h
@@ -11,6 +11,8 @@
 #define FADT_MAGIC "FACP"
 #define HPET_MAGIC "HPET"
 
+#define HPET_MAX_PERIOD 0x05F5E100
+
 struct address_structure {
 	u8 address_space_id;
 	u8 register_bit_width;
@@ -110,6 +112,6 @@ struct fadt *fadt;
 struct hpet *hpet;
 
 void acpi_install();
-void hpet_install(int period);
+void hpet_install(int frequency);
 
 #endif