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Diffstat (limited to 'src/cpu/p6/apic_timer.c')
-rw-r--r--src/cpu/p6/apic_timer.c26
1 files changed, 26 insertions, 0 deletions
diff --git a/src/cpu/p6/apic_timer.c b/src/cpu/p6/apic_timer.c
new file mode 100644
index 0000000000..fa7e9b905f
--- /dev/null
+++ b/src/cpu/p6/apic_timer.c
@@ -0,0 +1,26 @@
+#include <stdint.h>
+#include <delay.h>
+#include <cpu/p6/msr.h>
+#include <cpu/p6/apic.h>
+
+void init_timer(void)
+{
+ /* Set the apic timer to no interrupts and periodic mode */
+ apic_write(APIC_LVTT, (1 << 17)|(1<< 16)|(0 << 12)|(0 << 0));
+ /* Set the divider to 1, no divider */
+ apic_write(APIC_TDCR, APIC_TDR_DIV_1);
+ /* Set the initial counter to 0xffffffff */
+ apic_write(APIC_TMICT, 0xffffffff);
+}
+
+void udelay(unsigned usecs)
+{
+ uint32_t start, value, ticks;
+ /* Calculate the number of ticks to run, our FSB runs a 200Mhz */
+ ticks = usecs * 200;
+ start = apic_read(APIC_TMCCT);
+ do {
+ value = apic_read(APIC_TMCCT);
+ } while((start - value) < ticks);
+
+}