1 files changed, 145 insertions, 0 deletions
diff --git a/arch/arm/cpu/arm926ejs/at91/timer.c b/arch/arm/cpu/arm926ejs/at91/timer.c
new file mode 100644
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--- /dev/null
+++ b/arch/arm/cpu/arm926ejs/at91/timer.c
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+/*
+ * (C) Copyright 2007-2008
+ * Stelian Pop <stelian.pop@leadtechdesign.com>
+ * Lead Tech Design <www.leadtechdesign.com>
+ *
+ * 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/hardware.h>
+#include <asm/arch/at91_pit.h>
+#include <asm/arch/at91_pmc.h>
+#include <asm/arch/clk.h>
+#include <asm/arch/io.h>
+#include <div64.h>
+
+/*
+ * We're using the AT91CAP9/SAM9 PITC in 32 bit mode, by
+ * setting the 20 bit counter period to its maximum (0xfffff).
+ */
+#define TIMER_LOAD_VAL	0xfffff
+
+static ulong timestamp;
+static ulong lastinc;
+static ulong timer_freq;
+
+static inline unsigned long long tick_to_time(unsigned long long tick)
+{
+	tick *= CONFIG_SYS_HZ;
+	do_div(tick, timer_freq);
+
+	return tick;
+}
+
+static inline unsigned long long usec_to_tick(unsigned long long usec)
+{
+	usec *= timer_freq;
+	do_div(usec, 1000000);
+
+	return usec;
+}
+
+/* nothing really to do with interrupts, just starts up a counter. */
+int timer_init(void)
+{
+	at91_pmc_t *pmc = (at91_pmc_t *) AT91_PMC_BASE;
+	at91_pit_t *pit = (at91_pit_t *) AT91_PIT_BASE;
+	/*
+	 * Enable PITC Clock
+	 * The clock is already enabled for system controller in boot
+	 */
+	writel(1 << AT91_ID_SYS, &pmc->pcer);
+
+	/* Enable PITC */
+	writel(TIMER_LOAD_VAL | AT91_PIT_MR_EN , &pit->mr);
+
+	reset_timer_masked();
+
+	timer_freq = get_mck_clk_rate() >> 4;
+
+	return 0;
+}
+
+/*
+ * timer without interrupts
+ */
+unsigned long long get_ticks(void)
+{
+	at91_pit_t *pit = (at91_pit_t *) AT91_PIT_BASE;
+
+	ulong now = readl(&pit->piir);
+
+	if (now >= lastinc)	/* normal mode (non roll) */
+		/* move stamp forward with absolut diff ticks */
+		timestamp += (now - lastinc);
+	else			/* we have rollover of incrementer */
+		timestamp += (0xFFFFFFFF - lastinc) + now;
+	lastinc = now;
+	return timestamp;
+}
+
+void reset_timer_masked(void)
+{
+	/* reset time */
+	at91_pit_t *pit = (at91_pit_t *) AT91_PIT_BASE;
+
+	/* capture current incrementer value time */
+	lastinc = readl(&pit->piir);
+	timestamp = 0; /* start "advancing" time stamp from 0 */
+}
+
+ulong get_timer_masked(void)
+{
+	return tick_to_time(get_ticks());
+}
+
+void __udelay(unsigned long usec)
+{
+	unsigned long long tmp;
+	ulong tmo;
+
+	tmo = usec_to_tick(usec);
+	tmp = get_ticks() + tmo;	/* get current timestamp */
+
+	while (get_ticks() < tmp)	/* loop till event */
+		 /*NOP*/;
+}
+
+void reset_timer(void)
+{
+	reset_timer_masked();
+}
+
+ulong get_timer(ulong base)
+{
+	return get_timer_masked () - base;
+}
+
+/*
+ * 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 = CONFIG_SYS_HZ;
+	return tbclk;
+}