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-rw-r--r--arch/arm/cpu/arm1136/mx35/timer.c120
1 files changed, 120 insertions, 0 deletions
diff --git a/arch/arm/cpu/arm1136/mx35/timer.c b/arch/arm/cpu/arm1136/mx35/timer.c
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index 0000000000..db1e2c9d41
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+++ b/arch/arm/cpu/arm1136/mx35/timer.c
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+/*
+ * (C) Copyright 2007
+ * Sascha Hauer, Pengutronix
+ *
+ * (C) Copyright 2008-2009 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 <asm/arch/imx-regs.h>
+
+/* General purpose timers bitfields */
+#define GPTCR_SWR (1<<15) /* Software reset */
+#define GPTCR_FRR (1<<9) /* Freerun / restart */
+#define GPTCR_CLKSOURCE_32 (0x100<<6) /* Clock source */
+#define GPTCR_CLKSOURCE_IPG (0x001<<6) /* Clock source */
+#define GPTCR_TEN (1) /* Timer enable */
+#define GPTPR_VAL (66)
+
+int timer_init(void)
+{
+ int i;
+ struct gpt_regs *gpt = (struct gpt_regs *)GPT1_BASE_ADDR;
+
+ /* setup GP Timer 1 */
+ writel(GPTCR_SWR, &gpt->ctrl);
+ for (i = 0; i < 100; i++)
+ writel(0, &gpt->ctrl); /* We have no udelay by now */
+
+ writel(GPTPR_VAL, &gpt->pre);
+ /* Freerun Mode, PERCLK1 input */
+ writel(readl(&gpt->ctrl) |
+ GPTCR_CLKSOURCE_IPG | GPTCR_TEN,
+ &gpt->ctrl);
+
+ return 0;
+}
+
+void reset_timer_masked(void)
+{
+ struct gpt_regs *gpt = (struct gpt_regs *)GPT1_BASE_ADDR;
+
+ writel(0, &gpt->ctrl);
+ /* Freerun Mode, PERCLK1 input */
+ writel(GPTCR_CLKSOURCE_IPG | GPTCR_TEN,
+ &gpt->ctrl);
+}
+
+inline ulong get_timer_masked(void)
+{
+
+ struct gpt_regs *gpt = (struct gpt_regs *)GPT1_BASE_ADDR;
+ ulong val = readl(&gpt->counter);
+
+ return val;
+}
+
+void reset_timer(void)
+{
+ reset_timer_masked();
+}
+
+ulong get_timer(ulong base)
+{
+ ulong tmp;
+
+ tmp = get_timer_masked();
+
+ if (tmp <= (base * 1000)) {
+ /* Overflow */
+ tmp += (0xffffffff - base);
+ }
+
+ return (tmp / 1000) - base;
+}
+
+void set_timer(ulong t)
+{
+}
+
+/*
+ * delay x useconds AND preserve advance timstamp value
+ * GPTCNT is now supposed to tick 1 by 1 us.
+ */
+void __udelay(unsigned long usec)
+{
+ ulong tmp;
+
+ tmp = get_timer_masked(); /* get current timestamp */
+
+ /* if setting this forward will roll time stamp */
+ if ((usec + tmp + 1) < tmp) {
+ /* reset "advancing" timestamp to 0, set lastinc value */
+ reset_timer_masked();
+ } else {
+ /* else, set advancing stamp wake up time */
+ tmp += usec;
+ }
+
+ while (get_timer_masked() < tmp) /* loop till event */
+ /*NOP*/;
+}
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