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diff --git a/cpu/arm1176/s3c64xx/timer.c b/cpu/arm1176/s3c64xx/timer.c
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+/*
+ * (C) Copyright 2003
+ * Texas Instruments <www.ti.com>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Marius Groeger <mgroeger@sysgo.de>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Alex Zuepke <azu@sysgo.de>
+ *
+ * (C) Copyright 2002-2004
+ * Gary Jennejohn, DENX Software Engineering, <garyj@denx.de>
+ *
+ * (C) Copyright 2004
+ * Philippe Robin, ARM Ltd. <philippe.robin@arm.com>
+ *
+ * (C) Copyright 2008
+ * Guennadi Liakhovetki, DENX Software Engineering, <lg@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/proc-armv/ptrace.h>
+#include <s3c6400.h>
+#include <div64.h>
+
+static ulong timer_load_val;
+
+#define PRESCALER 167
+
+static s3c64xx_timers *s3c64xx_get_base_timers(void)
+{
+ return (s3c64xx_timers *)ELFIN_TIMER_BASE;
+}
+
+/* macro to read the 16 bit timer */
+static inline ulong read_timer(void)
+{
+ s3c64xx_timers *const timers = s3c64xx_get_base_timers();
+
+ return timers->TCNTO4;
+}
+
+/* Internal tick units */
+/* Last decremneter snapshot */
+static unsigned long lastdec;
+/* Monotonic incrementing timer */
+static unsigned long long timestamp;
+
+int timer_init(void)
+{
+ s3c64xx_timers *const timers = s3c64xx_get_base_timers();
+
+ /* use PWM Timer 4 because it has no output */
+ /*
+ * We use the following scheme for the timer:
+ * Prescaler is hard fixed at 167, divider at 1/4.
+ * This gives at PCLK frequency 66MHz approx. 10us ticks
+ * The timer is set to wrap after 100s, at 66MHz this obviously
+ * happens after 10,000,000 ticks. A long variable can thus
+ * keep values up to 40,000s, i.e., 11 hours. This should be
+ * enough for most uses:-) Possible optimizations: select a
+ * binary-friendly frequency, e.g., 1ms / 128. Also calculate
+ * the prescaler automatically for other PCLK frequencies.
+ */
+ timers->TCFG0 = PRESCALER << 8;
+ if (timer_load_val == 0) {
+ timer_load_val = get_PCLK() / PRESCALER * (100 / 4); /* 100s */
+ timers->TCFG1 = (timers->TCFG1 & ~0xf0000) | 0x20000;
+ }
+
+ /* load value for 10 ms timeout */
+ lastdec = timers->TCNTB4 = timer_load_val;
+ /* auto load, manual update of Timer 4 */
+ timers->TCON = (timers->TCON & ~0x00700000) | TCON_4_AUTO |
+ TCON_4_UPDATE;
+
+ /* auto load, start Timer 4 */
+ timers->TCON = (timers->TCON & ~0x00700000) | TCON_4_AUTO | COUNT_4_ON;
+ timestamp = 0;
+
+ return 0;
+}
+
+/*
+ * timer without interrupts
+ */
+
+/*
+ * 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)
+{
+ ulong now = read_timer();
+
+ if (lastdec >= now) {
+ /* normal mode */
+ timestamp += lastdec - now;
+ } else {
+ /* we have an overflow ... */
+ timestamp += lastdec + timer_load_val - now;
+ }
+ lastdec = now;
+
+ return timestamp;
+}
+
+/*
+ * 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)
+{
+ /* We overrun in 100s */
+ return (ulong)(timer_load_val / 100);
+}
+
+void reset_timer_masked(void)
+{
+ /* reset time */
+ lastdec = read_timer();
+ timestamp = 0;
+}
+
+void reset_timer(void)
+{
+ reset_timer_masked();
+}
+
+ulong get_timer_masked(void)
+{
+ unsigned long long res = get_ticks();
+ do_div (res, (timer_load_val / (100 * CONFIG_SYS_HZ)));
+ return res;
+}
+
+ulong get_timer(ulong base)
+{
+ return get_timer_masked() - base;
+}
+
+void set_timer(ulong t)
+{
+ timestamp = t * (timer_load_val / (100 * CONFIG_SYS_HZ));
+}
+
+void udelay(unsigned long usec)
+{
+ unsigned long long tmp;
+ ulong tmo;
+
+ tmo = (usec + 9) / 10;
+ tmp = get_ticks() + tmo; /* get current timestamp */
+
+ while (get_ticks() < tmp)/* loop till event */
+ /*NOP*/;
+}