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-rw-r--r--arch/avr32/cpu/interrupts.c128
1 files changed, 128 insertions, 0 deletions
diff --git a/arch/avr32/cpu/interrupts.c b/arch/avr32/cpu/interrupts.c
new file mode 100644
index 0000000..d87c6e1
--- /dev/null
+++ b/arch/avr32/cpu/interrupts.c
@@ -0,0 +1,128 @@
+/*
+ * Copyright (C) 2004-2006 Atmel Corporation
+ *
+ * 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 <div64.h>
+
+#include <asm/errno.h>
+#include <asm/io.h>
+#include <asm/processor.h>
+#include <asm/sysreg.h>
+
+#include <asm/arch/hardware.h>
+
+#define HANDLER_MASK 0x00ffffff
+#define INTLEV_SHIFT 30
+#define INTLEV_MASK 0x00000003
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* Incremented whenever COUNT reaches 0xffffffff by timer_interrupt_handler */
+volatile unsigned long timer_overflow;
+
+/*
+ * Instead of dividing by get_tbclk(), multiply by this constant and
+ * right-shift the result by 32 bits.
+ */
+static unsigned long tb_factor;
+
+unsigned long get_tbclk(void)
+{
+ return gd->arch.cpu_hz;
+}
+
+unsigned long long get_ticks(void)
+{
+ unsigned long lo, hi_now, hi_prev;
+
+ do {
+ hi_prev = timer_overflow;
+ lo = sysreg_read(COUNT);
+ hi_now = timer_overflow;
+ } while (hi_prev != hi_now);
+
+ return ((unsigned long long)hi_now << 32) | lo;
+}
+
+unsigned long get_timer(unsigned long base)
+{
+ u64 now = get_ticks();
+
+ now *= tb_factor;
+ return (unsigned long)(now >> 32) - base;
+}
+
+/*
+ * For short delays only. It will overflow after a few seconds.
+ */
+void __udelay(unsigned long usec)
+{
+ unsigned long cycles;
+ unsigned long base;
+ unsigned long now;
+
+ base = sysreg_read(COUNT);
+ cycles = ((usec * (get_tbclk() / 10000)) + 50) / 100;
+
+ do {
+ now = sysreg_read(COUNT);
+ } while ((now - base) < cycles);
+}
+
+static int set_interrupt_handler(unsigned int nr, void (*handler)(void),
+ unsigned int priority)
+{
+ extern void _evba(void);
+ unsigned long intpr;
+ unsigned long handler_addr = (unsigned long)handler;
+
+ handler_addr -= (unsigned long)&_evba;
+
+ if ((handler_addr & HANDLER_MASK) != handler_addr
+ || (priority & INTLEV_MASK) != priority)
+ return -EINVAL;
+
+ intpr = (handler_addr & HANDLER_MASK);
+ intpr |= (priority & INTLEV_MASK) << INTLEV_SHIFT;
+ writel(intpr, (void *)ATMEL_BASE_INTC + 4 * nr);
+
+ return 0;
+}
+
+int timer_init(void)
+{
+ extern void timer_interrupt_handler(void);
+ u64 tmp;
+
+ sysreg_write(COUNT, 0);
+
+ tmp = (u64)CONFIG_SYS_HZ << 32;
+ tmp += gd->arch.cpu_hz / 2;
+ do_div(tmp, gd->arch.cpu_hz);
+ tb_factor = (u32)tmp;
+
+ if (set_interrupt_handler(0, &timer_interrupt_handler, 3))
+ return -EINVAL;
+
+ /* For all practical purposes, this gives us an overflow interrupt */
+ sysreg_write(COMPARE, 0xffffffff);
+ return 0;
+}
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