1 files changed, 170 insertions, 0 deletions
diff --git a/cpu/arm1136/mx31/timer.c b/cpu/arm1136/mx31/timer.c
new file mode 100644
index 0000000..29b484e
--- /dev/null
+++ b/cpu/arm1136/mx31/timer.c
@@ -0,0 +1,170 @@
+/*
+ * (C) Copyright 2007
+ * Sascha Hauer, Pengutronix
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <asm/arch/mx31-regs.h>
+#include <div64.h>
+
+#define TIMER_BASE 0x53f90000 /* General purpose timer 1 */
+
+/* General purpose timers registers */
+#define GPTCR	__REG(TIMER_BASE)		/* Control register	*/
+#define GPTPR	__REG(TIMER_BASE + 0x4)		/* Prescaler register	*/
+#define GPTSR	__REG(TIMER_BASE + 0x8)		/* Status register	*/
+#define GPTCNT	__REG(TIMER_BASE + 0x24)	/* Counter register	*/
+
+/* General purpose timers bitfields */
+#define GPTCR_SWR		(1 << 15)	/* Software reset	*/
+#define GPTCR_FRR		(1 << 9)	/* Freerun / restart	*/
+#define GPTCR_CLKSOURCE_32	(4 << 6)	/* Clock source		*/
+#define GPTCR_TEN		1		/* Timer enable		*/
+
+static ulong timestamp;
+static ulong lastinc;
+
+/* "time" is measured in 1 / CONFIG_SYS_HZ seconds, "tick" is internal timer period */
+#ifdef CONFIG_MX31_TIMER_HIGH_PRECISION
+/* ~0.4% error - measured with stop-watch on 100s boot-delay */
+static inline unsigned long long tick_to_time(unsigned long long tick)
+{
+	tick *= CONFIG_SYS_HZ;
+	do_div(tick, CONFIG_MX31_CLK32);
+	return tick;
+}
+
+static inline unsigned long long time_to_tick(unsigned long long time)
+{
+	time *= CONFIG_MX31_CLK32;
+	do_div(time, CONFIG_SYS_HZ);
+	return time;
+}
+
+static inline unsigned long long us_to_tick(unsigned long long us)
+{
+	us = us * CONFIG_MX31_CLK32 + 999999;
+	do_div(us, 1000000);
+	return us;
+}
+#else
+/* ~2% error */
+#define TICK_PER_TIME	((CONFIG_MX31_CLK32 + CONFIG_SYS_HZ / 2) / CONFIG_SYS_HZ)
+#define US_PER_TICK	(1000000 / CONFIG_MX31_CLK32)
+
+static inline unsigned long long tick_to_time(unsigned long long tick)
+{
+	do_div(tick, TICK_PER_TIME);
+	return tick;
+}
+
+static inline unsigned long long time_to_tick(unsigned long long time)
+{
+	return time * TICK_PER_TIME;
+}
+
+static inline unsigned long long us_to_tick(unsigned long long us)
+{
+	us += US_PER_TICK - 1;
+	do_div(us, US_PER_TICK);
+	return us;
+}
+#endif
+
+/* The 32768Hz 32-bit timer overruns in 131072 seconds */
+int timer_init (void)
+{
+	int i;
+
+	/* setup GP Timer 1 */
+	GPTCR = GPTCR_SWR;
+	for (i = 0; i < 100; i++)
+		GPTCR = 0; /* We have no udelay by now */
+	GPTPR = 0; /* 32Khz */
+	/* Freerun Mode, PERCLK1 input */
+	GPTCR |= GPTCR_CLKSOURCE_32 | GPTCR_TEN;
+
+	return 0;
+}
+
+void reset_timer_masked (void)
+{
+	/* reset time */
+	lastinc = GPTCNT; /* capture current incrementer value time */
+	timestamp = 0; /* start "advancing" time stamp from 0 */
+}
+
+void reset_timer(void)
+{
+	reset_timer_masked();
+}
+
+unsigned long long get_ticks (void)
+{
+	ulong now = GPTCNT; /* current tick value */
+
+	if (now >= lastinc)	/* normal mode (non roll) */
+		/* move stamp forward with absolut diff ticks */
+		timestamp += (now - lastinc);
+	else			/* we have rollover of incrementer */
+		timestamp += (0xFFFFFFFF - lastinc) + now;
+	lastinc = now;
+	return timestamp;
+}
+
+ulong get_timer_masked (void)
+{
+	/*
+	 * get_ticks() returns a long long (64 bit), it wraps in
+	 * 2^64 / CONFIG_MX31_CLK32 = 2^64 / 2^15 = 2^49 ~ 5 * 10^14 (s) ~
+	 * 5 * 10^9 days... and get_ticks() * CONFIG_SYS_HZ wraps in
+	 * 5 * 10^6 days - long enough.
+	 */
+	return tick_to_time(get_ticks());
+}
+
+ulong get_timer (ulong base)
+{
+	return get_timer_masked () - base;
+}
+
+void set_timer (ulong t)
+{
+	timestamp = time_to_tick(t);
+}
+
+/* delay x useconds AND perserve advance timstamp value */
+void udelay (unsigned long usec)
+{
+	unsigned long long tmp;
+	ulong tmo;
+
+	tmo = us_to_tick(usec);
+	tmp = get_ticks() + tmo;	/* get current timestamp */
+
+	while (get_ticks() < tmp)	/* loop till event */
+		 /*NOP*/;
+}
+
+void reset_cpu (ulong addr)
+{
+	__REG16(WDOG_BASE) = 4;
+}