new rng, some rework of I/O

1 files changed, 21 insertions, 3 deletions

diff --git a/kernel/timer.c b/kernel/timer.c
index 571fcbe..2fbd8eb 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -1,10 +1,11 @@
 #include <stdint.h>
+#include "io.h"
 #include "isr.h"
 #include "timer.h"
 
-uint64_t current_tick_data = 0;
+volatile uint64_t current_tick_data = 0;
 
-const uint64_t *current_tick = &current_tick_data;
+volatile const uint64_t *current_tick = &current_tick_data;
 
 static void timer_callback(struct regs_t regs)
 {
@@ -12,7 +13,24 @@ static void timer_callback(struct regs_t regs)
     ++current_tick_data;
 }
 
-void timer_init(void)
+void timer_init(uint32_t freq)
 {
     set_interrupt_handler(IRQ(0), timer_callback);
+
+    current_tick_data = 0;
+
+    uint32_t divisor = PIT_FREQ / freq;
+
+    uint8_t hi = (divisor >> 8) & 0xFF;
+    uint8_t lo = (divisor >> 0) & 0xFF;
+
+    outb(0x43, 0x36);
+    outb(0x40, lo);
+    outb(0x40, hi);
+}
+
+void timer_delay(uint64_t ticks)
+{
+    uint64_t end = *current_tick + ticks;
+    while(*current_tick <= end);
 }