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Diffstat (limited to 'arch/mips/mipssim/sim_int.c')
-rw-r--r--arch/mips/mipssim/sim_int.c88
1 files changed, 88 insertions, 0 deletions
diff --git a/arch/mips/mipssim/sim_int.c b/arch/mips/mipssim/sim_int.c
new file mode 100644
index 000000000000..d86b37235cf6
--- /dev/null
+++ b/arch/mips/mipssim/sim_int.c
@@ -0,0 +1,88 @@
+/*
+ * Copyright (C) 1999, 2005 MIPS Technologies, Inc. All rights reserved.
+ *
+ * This program is free software; you can distribute it and/or modify it
+ * under the terms of the GNU General Public License (Version 2) as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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 <linux/init.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+#include <asm/mips-boards/simint.h>
+#include <asm/irq_cpu.h>
+
+static inline int clz(unsigned long x)
+{
+ __asm__ (
+ " .set push \n"
+ " .set mips32 \n"
+ " clz %0, %1 \n"
+ " .set pop \n"
+ : "=r" (x)
+ : "r" (x));
+
+ return x;
+}
+
+/*
+ * Version of ffs that only looks at bits 12..15.
+ */
+static inline unsigned int irq_ffs(unsigned int pending)
+{
+#if defined(CONFIG_CPU_MIPS32) || defined(CONFIG_CPU_MIPS64)
+ return -clz(pending) + 31 - CAUSEB_IP;
+#else
+ unsigned int a0 = 7;
+ unsigned int t0;
+
+ t0 = s0 & 0xf000;
+ t0 = t0 < 1;
+ t0 = t0 << 2;
+ a0 = a0 - t0;
+ s0 = s0 << t0;
+
+ t0 = s0 & 0xc000;
+ t0 = t0 < 1;
+ t0 = t0 << 1;
+ a0 = a0 - t0;
+ s0 = s0 << t0;
+
+ t0 = s0 & 0x8000;
+ t0 = t0 < 1;
+ /* t0 = t0 << 2; */
+ a0 = a0 - t0;
+ /* s0 = s0 << t0; */
+
+ return a0;
+#endif
+}
+
+asmlinkage void plat_irq_dispatch(void)
+{
+ unsigned int pending = read_c0_cause() & read_c0_status() & ST0_IM;
+ int irq;
+
+ irq = irq_ffs(pending);
+
+ if (irq > 0)
+ do_IRQ(MIPSCPU_INT_BASE + irq);
+ else
+ spurious_interrupt();
+}
+
+void __init arch_init_irq(void)
+{
+ mips_cpu_irq_init();
+}