1 files changed, 123 insertions, 0 deletions
diff --git a/cpu/arm_cortexa8/mx51/timer.c b/cpu/arm_cortexa8/mx51/timer.c
new file mode 100644
index 0000000..ff982be
--- /dev/null
+++ b/cpu/arm_cortexa8/mx51/timer.c
@@ -0,0 +1,123 @@
+/*
+ * (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/arch/mx51.h>
+
+/* General purpose timers registers */
+#define GPTCR   __REG(GPT1_BASE_ADDR)	/* Control register */
+#define GPTPR  	__REG(GPT1_BASE_ADDR + 0x4)	/* Prescaler register */
+#define GPTSR   __REG(GPT1_BASE_ADDR + 0x8)	/* Status register */
+#define GPTCNT 	__REG(GPT1_BASE_ADDR + 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 inline void setup_gpt()
+{
+	int i;
+	static int init_done;
+
+	if (init_done)
+	    return;
+
+	init_done = 1;
+
+	/* 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;
+}
+
+/* nothing really to do with interrupts, just starts up a counter. */
+int timer_init(void)
+{
+	setup_gpt();
+
+	return 0;
+}
+
+void reset_timer(void)
+{
+	reset_timer_masked();
+}
+
+void reset_timer_masked(void)
+{
+	GPTCR = 0;
+	/* Freerun Mode, PERCLK1 input */
+	GPTCR = GPTCR_CLKSOURCE_32 | GPTCR_TEN;
+}
+
+ulong get_timer_masked(void)
+{
+	ulong val = GPTCNT;
+	return val;
+}
+
+ulong get_timer(ulong base)
+{
+	return get_timer_masked() - base;
+}
+
+void set_timer(ulong t)
+{
+}
+
+/* delay x useconds AND perserve advance timstamp value */
+void udelay(unsigned long usec)
+{
+	ulong tmo, tmp;
+
+	setup_gpt();
+
+	/* if "big" number, spread normalization to seconds */
+	if (usec >= 1000) {
+		/* start to normalize for usec to ticks per sec */
+		tmo = usec / 1000;
+		/* find number of "ticks" to wait to achieve target */
+		tmo *= CONFIG_SYS_HZ;
+		tmo /= 1000;	/* finish normalize. */
+	} else {/* else small number, don't kill it prior to HZ multiply */
+		tmo = usec * CONFIG_SYS_HZ;
+		tmo /= (1000 * 1000);
+	}
+
+	tmp = get_timer(0);	/* get current timestamp */
+	/* if setting this forward will roll time stamp */
+	if ((tmo + tmp + 1) < tmp)
+		 /* reset "advancing" timestamp to 0, set lastinc value */
+		reset_timer_masked();
+	else	/* else, set advancing stamp wake up time */
+		tmo += tmp;
+	while (get_timer_masked() < tmo)	/* loop till event */
+		 /*NOP*/;
+}