1 files changed, 149 insertions, 0 deletions
diff --git a/arch/arm/imx-common/timer.c b/arch/arm/imx-common/timer.c
new file mode 100644
index 0000000000..e2725e1a64
--- /dev/null
+++ b/arch/arm/imx-common/timer.c
@@ -0,0 +1,149 @@
+/*
+ * (C) Copyright 2007
+ * Sascha Hauer, Pengutronix
+ *
+ * (C) Copyright 2009 Freescale Semiconductor, Inc.
+ *
+ * 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/io.h>
+#include <div64.h>
+#include <asm/arch/imx-regs.h>
+
+/* General purpose timers registers */
+struct mxc_gpt {
+	unsigned int control;
+	unsigned int prescaler;
+	unsigned int status;
+	unsigned int nouse[6];
+	unsigned int counter;
+};
+
+static struct mxc_gpt *cur_gpt = (struct mxc_gpt *)GPT1_BASE_ADDR;
+
+/* 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 */
+#define CLK_32KHZ		32768		/* 32Khz input */
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define timestamp (gd->tbl)
+#define lastinc (gd->lastinc)
+
+static inline unsigned long long tick_to_time(unsigned long long tick)
+{
+	tick *= CONFIG_SYS_HZ;
+	do_div(tick, CLK_32KHZ);
+
+	return tick;
+}
+
+static inline unsigned long long us_to_tick(unsigned long long usec)
+{
+	usec = usec * CLK_32KHZ + 999999;
+	do_div(usec, 1000000);
+
+	return usec;
+}
+
+int timer_init(void)
+{
+	int i;
+	ulong val;
+
+	/* setup GP Timer 1 */
+	__raw_writel(GPTCR_SWR, &cur_gpt->control);
+
+	/* We have no udelay by now */
+	for (i = 0; i < 100; i++)
+		__raw_writel(0, &cur_gpt->control);
+
+	__raw_writel(0, &cur_gpt->prescaler); /* 32Khz */
+
+	/* Freerun Mode, PERCLK1 input */
+	i = __raw_readl(&cur_gpt->control);
+	__raw_writel(i | GPTCR_CLKSOURCE_32 | GPTCR_TEN, &cur_gpt->control);
+
+	val = __raw_readl(&cur_gpt->counter);
+	lastinc = val / (CLK_32KHZ / CONFIG_SYS_HZ);
+	timestamp = 0;
+
+	return 0;
+}
+
+unsigned long long get_ticks(void)
+{
+	ulong now = __raw_readl(&cur_gpt->counter); /* 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_MX25_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;
+}
+
+/* delay x useconds AND preserve 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*/;
+}
+
+/*
+ * This function is derived from PowerPC code (timebase clock frequency).
+ * On ARM it returns the number of timer ticks per second.
+ */
+ulong get_tbclk(void)
+{
+	return CLK_32KHZ;
+}