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Diffstat (limited to 'arch/arm/cpu/armv7/mx51/timer.c')
-rw-r--r--arch/arm/cpu/armv7/mx51/timer.c119
1 files changed, 119 insertions, 0 deletions
diff --git a/arch/arm/cpu/armv7/mx51/timer.c b/arch/arm/cpu/armv7/mx51/timer.c
new file mode 100644
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+++ b/arch/arm/cpu/armv7/mx51/timer.c
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+/*
+ * (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 <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 */
+
+static ulong timestamp;
+static ulong lastinc;
+
+int timer_init(void)
+{
+ int i;
+
+ /* 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);
+ reset_timer_masked();
+ return 0;
+}
+
+void reset_timer(void)
+{
+ reset_timer_masked();
+}
+
+void reset_timer_masked(void)
+{
+ ulong val = __raw_readl(&cur_gpt->counter);
+ lastinc = val / (CONFIG_MX51_CLK32 / CONFIG_SYS_HZ);
+ timestamp = 0;
+}
+
+ulong get_timer_masked(void)
+{
+ ulong val = __raw_readl(&cur_gpt->counter);
+ val /= (CONFIG_MX51_CLK32 / CONFIG_SYS_HZ);
+ if (val >= lastinc)
+ timestamp += (val - lastinc);
+ else
+ timestamp += ((0xFFFFFFFF / (CONFIG_MX51_CLK32 / CONFIG_SYS_HZ))
+ - lastinc) + val;
+ lastinc = val;
+ return val;
+}
+
+ulong get_timer(ulong base)
+{
+ return get_timer_masked() - base;
+}
+
+void set_timer(ulong t)
+{
+ timestamp = t;
+}
+
+/* delay x useconds AND preserve advance timestamp value */
+void __udelay(unsigned long usec)
+{
+ unsigned long now, start, tmo;
+ tmo = usec * (CONFIG_MX51_CLK32 / 1000) / 1000;
+
+ if (!tmo)
+ tmo = 1;
+
+ now = start = readl(&cur_gpt->counter);
+
+ while ((now - start) < tmo)
+ now = readl(&cur_gpt->counter);
+
+}