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+/*
+ * (C) Copyright 2004
+ * Texas Instruments
+ * Richard Woodruff <r-woodruff2@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, <gj@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/arch/bits.h>
+#include <asm/arch/omap2420.h>
+
+#define TIMER_LOAD_VAL 0
+
+/* macro to read the 32 bit timer */
+#define READ_TIMER (*volatile ulong*(CFG_TIMERBASE+TCRR))
+
+static ulong timestamp;
+static ulong lastinc;
+
+/*
+ * nothing really to do with interrupts, just starts up a counter.
+ */
+int interrupt_init(void)
+{
+ int32_t val;
+
+ /* Start the counter ticking up */
+ /* reload value on overflow*/
+ *((int32_t *) (CFG_TIMERBASE + TLDR)) = TIMER_LOAD_VAL;
+ /* mask to enable timer*/
+ val = (CFG_PVT << 2) | BIT5 | BIT1 | BIT0;
+ *((int32_t *) (CFG_TIMERBASE + TCLR)) = val; /* start timer */
+
+ reset_timer_masked(); /* init the timestamp and lastinc value */
+
+ return(0);
+}
+/*
+ * timer without interrupts
+ */
+void reset_timer(void)
+{
+ reset_timer_masked();
+}
+
+ulong get_timer(ulong base)
+{
+ return get_timer_masked() - base;
+}
+
+void set_timer(ulong t)
+{
+ timestamp = t;
+}
+
+/* delay x useconds AND perserve advance timstamp value */
+void udelay(unsigned long usec)
+{
+ ulong tmo, tmp;
+
+ /* 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 *= CFG_HZ;
+ /* finish normalize. */
+ tmo /= 1000;
+ } else {
+ /* else small number, don't kill it prior to HZ multiply */
+ tmo = usec * CFG_HZ;
+ tmo /= (1000*1000);
+ }
+ /* get current timestamp */
+ tmp = get_timer(0);
+ if ((tmo + tmp + 1) < tmp)
+ /* setting this forward will roll time stamp */
+ /* 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*/;
+}
+
+void reset_timer_masked(void)
+{
+ /* reset time */
+ /* capture current incrementer value time */
+ lastinc = READ_TIMER;
+ /* start "advancing" time stamp from 0 */
+ timestamp = 0;
+}
+
+ulong get_timer_masked(void)
+{
+ ulong now = READ_TIMER; /* current tick value */
+
+ /* normal mode (non roll) */
+ if (now >= lastinc)
+ /* move stamp forward with absolute diff ticks */
+ timestamp += (now - lastinc);
+ else
+ /* we have rollover of incrementer */
+ timestamp += (0xFFFFFFFF - lastinc) + now;
+ lastinc = now;
+ return timestamp;
+}
+
+/* waits specified delay value and resets timestamp */
+void udelay_masked(unsigned long usec)
+{
+ ulong tmo;
+ ulong endtime;
+ signed long diff;
+
+ if (usec >= 1000) {
+ /* "big" number, spread normalization to seconds */
+ /* start to normalize for usec to ticks per sec */
+ tmo = usec / 1000;
+ /* find number of "ticks" to wait to achieve target */
+ tmo *= CFG_HZ;
+ tmo /= 1000;/* finish normalize. */
+ } else {
+ /* else small number, don't kill it prior to HZ multiply */
+ tmo = usec * CFG_HZ;
+ tmo /= (1000*1000);
+ }
+ endtime = get_timer_masked() + tmo;
+
+ do {
+ ulong now = get_timer_masked();
+ diff = endtime - now;
+ } while (diff >= 0);
+}
+
+/*
+ * 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)
+{
+ ulong tbclk;
+ tbclk = CFG_HZ;
+ return tbclk;
+}