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Diffstat (limited to 'arch/arm/cpu/tegra-common/timer.c')
-rw-r--r--arch/arm/cpu/tegra-common/timer.c111
1 files changed, 111 insertions, 0 deletions
diff --git a/arch/arm/cpu/tegra-common/timer.c b/arch/arm/cpu/tegra-common/timer.c
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+++ b/arch/arm/cpu/tegra-common/timer.c
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+/*
+ * (C) Copyright 2010,2011
+ * NVIDIA Corporation <www.nvidia.com>
+ *
+ * (C) Copyright 2008
+ * Texas Instruments
+ *
+ * Richard Woodruff <r-woodruff2@ti.com>
+ * Syed Moahmmed Khasim <khasim@ti.com>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Marius Groeger <mgroeger@sysgo.de>
+ * Alex Zuepke <azu@sysgo.de>
+ *
+ * (C) Copyright 2002
+ * Gary Jennejohn, DENX Software Engineering, <garyj@denx.de>
+ *
+ * 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/tegra20.h>
+#include <asm/arch/timer.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* counter runs at 1MHz */
+#define TIMER_CLK 1000000
+#define TIMER_LOAD_VAL 0xffffffff
+
+/* timer without interrupts */
+ulong get_timer(ulong base)
+{
+ return get_timer_masked() - base;
+}
+
+/* delay x useconds */
+void __udelay(unsigned long usec)
+{
+ long tmo = usec * (TIMER_CLK / 1000) / 1000;
+ unsigned long now, last = timer_get_us();
+
+ while (tmo > 0) {
+ now = timer_get_us();
+ if (last > now) /* count up timer overflow */
+ tmo -= TIMER_LOAD_VAL - last + now;
+ else
+ tmo -= now - last;
+ last = now;
+ }
+}
+
+ulong get_timer_masked(void)
+{
+ ulong now;
+
+ /* current tick value */
+ now = timer_get_us() / (TIMER_CLK / CONFIG_SYS_HZ);
+
+ if (now >= gd->lastinc) /* normal mode (non roll) */
+ /* move stamp forward with absolute diff ticks */
+ gd->tbl += (now - gd->lastinc);
+ else /* we have rollover of incrementer */
+ gd->tbl += ((TIMER_LOAD_VAL / (TIMER_CLK / CONFIG_SYS_HZ))
+ - gd->lastinc) + now;
+ gd->lastinc = now;
+ return gd->tbl;
+}
+
+/*
+ * This function is derived from PowerPC code (read timebase as long long).
+ * On ARM it just returns the timer value.
+ */
+unsigned long long get_ticks(void)
+{
+ return get_timer(0);
+}
+
+/*
+ * 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 CONFIG_SYS_HZ;
+}
+
+unsigned long timer_get_us(void)
+{
+ struct timerus *timer_base = (struct timerus *)NV_PA_TMRUS_BASE;
+
+ return readl(&timer_base->cntr_1us);
+}