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-rw-r--r--arch/arm/cpu/ixp/timer.c135
1 files changed, 135 insertions, 0 deletions
diff --git a/arch/arm/cpu/ixp/timer.c b/arch/arm/cpu/ixp/timer.c
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+++ b/arch/arm/cpu/ixp/timer.c
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+/*
+ * (C) Copyright 2006
+ * Stefan Roese, DENX Software Engineering, sr@denx.de.
+ *
+ * (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>
+ *
+ * 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/ixp425.h>
+
+#ifdef CONFIG_TIMER_IRQ
+
+#define FREQ 66666666
+#define CLOCK_TICK_RATE (((FREQ / CONFIG_SYS_HZ & ~IXP425_OST_RELOAD_MASK) + 1) * CONFIG_SYS_HZ)
+#define LATCH ((CLOCK_TICK_RATE + CONFIG_SYS_HZ/2) / CONFIG_SYS_HZ) /* For divider */
+
+/*
+ * When interrupts are enabled, use timer 2 for time/delay generation...
+ */
+
+static volatile ulong timestamp;
+
+static void timer_isr(void *data)
+{
+ unsigned int *pTime = (unsigned int *)data;
+
+ (*pTime)++;
+
+ /*
+ * Reset IRQ source
+ */
+ *IXP425_OSST = IXP425_OSST_TIMER_2_PEND;
+}
+
+ulong get_timer (ulong base)
+{
+ return timestamp - base;
+}
+
+void reset_timer (void)
+{
+ timestamp = 0;
+}
+
+int timer_init (void)
+{
+ /* install interrupt handler for timer */
+ irq_install_handler(IXP425_TIMER_2_IRQ, timer_isr, (void *)&timestamp);
+
+ /* setup the Timer counter value */
+ *IXP425_OSRT2 = (LATCH & ~IXP425_OST_RELOAD_MASK) | IXP425_OST_ENABLE;
+
+ /* enable timer irq */
+ *IXP425_ICMR = (1 << IXP425_TIMER_2_IRQ);
+
+ return 0;
+}
+#else
+ulong get_timer (ulong base)
+{
+ return get_timer_masked () - base;
+}
+
+void ixp425_udelay(unsigned long usec)
+{
+ /*
+ * This function has a max usec, but since it is called from udelay
+ * we should not have to worry... be happy
+ */
+ unsigned long usecs = CONFIG_SYS_HZ/1000000L & ~IXP425_OST_RELOAD_MASK;
+
+ *IXP425_OSST = IXP425_OSST_TIMER_1_PEND;
+ usecs |= IXP425_OST_ONE_SHOT | IXP425_OST_ENABLE;
+ *IXP425_OSRT1 = usecs;
+ while (!(*IXP425_OSST & IXP425_OSST_TIMER_1_PEND));
+}
+
+void __udelay (unsigned long usec)
+{
+ while (usec--) ixp425_udelay(1);
+}
+
+static ulong reload_constant = 0xfffffff0;
+
+void reset_timer_masked (void)
+{
+ ulong reload = reload_constant | IXP425_OST_ONE_SHOT | IXP425_OST_ENABLE;
+
+ *IXP425_OSST = IXP425_OSST_TIMER_1_PEND;
+ *IXP425_OSRT1 = reload;
+}
+
+ulong get_timer_masked (void)
+{
+ /*
+ * Note that it is possible for this to wrap!
+ * In this case we return max.
+ */
+ ulong current = *IXP425_OST1;
+ if (*IXP425_OSST & IXP425_OSST_TIMER_1_PEND)
+ {
+ return reload_constant;
+ }
+ return (reload_constant - current);
+}
+
+int timer_init(void)
+{
+ return 0;
+}
+#endif