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-rw-r--r--cpu/nios/interrupts.c184
1 files changed, 184 insertions, 0 deletions
diff --git a/cpu/nios/interrupts.c b/cpu/nios/interrupts.c
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+++ b/cpu/nios/interrupts.c
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+/*
+ * (C) Copyright 2000-2002
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * (C) Copyright 2003, Psyent Corporation <www.psyent.com>
+ * Scott McNutt <smcnutt@psyent.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 <nios.h>
+#include <nios-io.h>
+#include <asm/ptrace.h>
+#include <common.h>
+#include <command.h>
+
+/****************************************************************************/
+
+struct irq_action {
+ interrupt_handler_t *handler;
+ void *arg;
+ int count;
+};
+
+static struct irq_action irq_vecs[64];
+
+/*************************************************************************/
+volatile ulong timestamp = 0;
+
+void reset_timer (void)
+{
+ timestamp = 0;
+}
+
+ulong get_timer (ulong base)
+{
+ return (timestamp - base);
+}
+
+void set_timer (ulong t)
+{
+ timestamp = t;
+}
+
+
+/* The board must handle this interrupt if a timer is not
+ * provided.
+ */
+#if defined(CFG_NIOS_TMRBASE)
+void timer_interrupt (struct pt_regs *regs)
+{
+ /* Interrupt is cleared by writing anything to the
+ * status register.
+ */
+ nios_timer_t *tmr = (nios_timer_t *)CFG_NIOS_TMRBASE;
+ tmr->status = 0;
+ timestamp += CFG_NIOS_TMRMS;
+}
+#endif
+
+/*************************************************************************/
+int disable_interrupts (void)
+{
+ int val = 0;
+
+ /* Writing anything to CLR_IE disables interrupts */
+ val = rdctl (CTL_STATUS);
+ wrctl (CTL_CLR_IE, 0);
+ return (val & STATUS_IE);
+}
+
+void enable_interrupts( void )
+{
+ /* Writing anything SET_IE enables interrupts */
+ wrctl (CTL_SET_IE, 0);
+}
+
+void external_interrupt (struct pt_regs *regs)
+{
+ unsigned vec;
+
+ vec = (regs->status & STATUS_IPRI) >> 9; /* ipri */
+
+ irq_vecs[vec].count++;
+ if (irq_vecs[vec].handler != NULL) {
+ (*irq_vecs[vec].handler)(irq_vecs[vec].arg);
+ } else {
+ /* A sad side-effect of masking a bogus interrupt is
+ * that lower priority interrupts will also be disabled.
+ * This is probably not what we want ... so hang insted.
+ */
+ printf ("Unhandled interrupt: 0x%x\n", vec);
+ disable_interrupts ();
+ hang ();
+ }
+}
+
+/*************************************************************************/
+int interrupt_init (void)
+{
+ int vec;
+
+#if defined(CFG_NIOS_TMRBASE)
+ nios_timer_t *tmr = (nios_timer_t *)CFG_NIOS_TMRBASE;
+
+ tmr->control &= ~NIOS_TIMER_ITO;
+ tmr->control |= NIOS_TIMER_STOP;
+#endif
+
+ for (vec=0; vec<64; vec++ ) {
+ irq_vecs[vec].handler = NULL;
+ irq_vecs[vec].arg = NULL;
+ irq_vecs[vec].count = 0;
+ }
+
+ /* Need timus interruptus -- start the lopri timer */
+#if defined(CFG_NIOS_TMRBASE)
+ tmr->control |= ( NIOS_TIMER_ITO |
+ NIOS_TIMER_CONT |
+ NIOS_TIMER_START );
+ ipri (CFG_NIOS_TMRIRQ + 1);
+#endif
+ enable_interrupts ();
+ return (0);
+}
+
+void irq_install_handler (int vec, interrupt_handler_t *handler, void *arg)
+{
+ struct irq_action *irqa = irq_vecs;
+ int i = vec;
+ int flag;
+
+ if (irqa[i].handler != NULL) {
+ printf ("Interrupt vector %d: handler 0x%x "
+ "replacing 0x%x\n",
+ vec, (uint)handler, (uint)irqa[i].handler);
+ }
+
+ flag = disable_interrupts ();
+ irqa[i].handler = handler;
+ irqa[i].arg = arg;
+ if (flag )
+ enable_interrupts ();
+}
+
+/*************************************************************************/
+#if (CONFIG_COMMANDS & CFG_CMD_IRQ)
+int do_irqinfo (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+{
+ int vec;
+
+ printf ("\nInterrupt-Information:\n");
+ printf ("Nr Routine Arg CouIt's ok to cnt\n");
+
+ for (vec=0; vec<64; vec++) {
+ if (irq_vecs[vec].handler != NULL) {
+ printf ("%02d %08lx %08lx %d\n",
+ vec,
+ (ulong)irq_vecs[vec].handler<<1,
+ (ulong)irq_vecs[vec].arg,
+ irq_vecs[vec].count);
+ }
+ }
+
+ return (0);
+}
+#endif /* CONFIG_COMMANDS & CFG_CMD_IRQ */