A27R版本修改

A58-AMTLDR/Src/timer.c

@@ -0,0 +1,78 @@
+#include "amt630h.h"
+#include "timer.h"
+
+#define APBTMR_CONTROL_ENABLE			(1 << 0)
+/* 1: periodic, 0:free running. */
+#define APBTMR_CONTROL_MODE_PERIODIC	(1 << 1)
+#define APBTMR_CONTROL_INT_DISABLE		(1 << 2)
+
+#define TIMER_CLK		CLK_24MHZ
+#define TIMER_PERIOD	1000000
+#define TIMER_LOAD_VAL	0xffffffff
+
+static unsigned long timestamp;
+static unsigned long lastdec;
+
+void timer_init(void)
+{
+	rTIMER0_CONTROL = 0;
+	rTIMER0_LOAD_COUNT = TIMER_LOAD_VAL;
+	/* No timer interrupt */
+	rTIMER0_CONTROL =  APBTMR_CONTROL_INT_DISABLE |
+					   APBTMR_CONTROL_MODE_PERIODIC | APBTMR_CONTROL_ENABLE;
+}
+
+void udelay(unsigned long usec)
+{
+	long tmo = usec * (TIMER_CLK / TIMER_PERIOD);
+	unsigned long last = rTIMER0_CURRENT_VALUE;
+	unsigned long now;
+
+	while (tmo > 0) {
+		now = rTIMER0_CURRENT_VALUE;
+		if (last >= now)
+			tmo -= last - now;
+		else
+			tmo -= last + (TIMER_LOAD_VAL - now);
+		last = now;
+	}
+}
+
+void mdelay(unsigned long msec)
+{
+	udelay(1000*msec);
+}
+
+#if 0
+void reset_timer_masked (void)
+{
+	/* reset time */
+	lastdec = rTIMER0_CURRENT_VALUE;  /* capure current decrementer value time */
+	timestamp = 0;         /* start "advancing" time stamp from 0 */
+}
+#endif
+
+ULONG get_timer_masked (void)
+{
+	unsigned long now = rTIMER0_CURRENT_VALUE;            /* current tick value */
+
+	if (lastdec >= now) {            /* normal mode (non roll) */
+		/* normal mode */
+		timestamp += lastdec - now; /* move stamp fordward with absoulte diff ticks */
+	} else {                        /* we have overflow of the count down timer */
+		/* nts = ts + ld + (TLV - now)
+		 * ts=old stamp, ld=time that passed before passing through -1
+		 * (TLV-now) amount of time after passing though -1
+		 * nts = new "advancing time stamp"...it could also roll and cause problems.
+		 */
+		timestamp += lastdec + (TIMER_LOAD_VAL - now);
+	}
+	lastdec = now;
+
+	return timestamp / DIV_ROUND_UP(TIMER_CLK, TIMER_PERIOD) / 1000;
+}
+
+ULONG get_timer(ULONG base)
+{
+	return get_timer_masked () - base;
+}