kernel: add standard clock system

kernel/clock.c

@@ -0,0 +1,29 @@
+#include <socks/clock.h>
+#include <socks/printk.h>
+#include <socks/compiler.h>
+
+static clock_ticks_t ticks_per_sec = 0;
+volatile clock_ticks_t clock_ticks = 0;
+
+clock_ticks_t clock_hz(void)
+{
+	return ticks_per_sec;
+}
+
+void clock_calibrate(clock_ticks_t hz)
+{
+	ticks_per_sec = hz;
+}
+
+void clock_advance(clock_ticks_t ticks)
+{
+	clock_ticks += ticks;
+}
+
+void clock_wait(clock_ticks_t ticks)
+{
+	clock_ticks_t end = clock_ticks + ticks;
+	while (clock_ticks < end) {
+
+	}
+}