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-rw-r--r--arch/mips/mips-boards/atlas/atlas_int.c142
1 files changed, 142 insertions, 0 deletions
diff --git a/arch/mips/mips-boards/atlas/atlas_int.c b/arch/mips/mips-boards/atlas/atlas_int.c
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+++ b/arch/mips/mips-boards/atlas/atlas_int.c
@@ -0,0 +1,142 @@
+/*
+ * Carsten Langgaard, carstenl@mips.com
+ * Copyright (C) 1999,2000 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.
+ *
+ * ########################################################################
+ *
+ * Routines for generic manipulation of the interrupts found on the MIPS
+ * Atlas board.
+ *
+ */
+#include <linux/compiler.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+
+#include <asm/irq.h>
+#include <asm/io.h>
+#include <asm/mips-boards/atlas.h>
+#include <asm/mips-boards/atlasint.h>
+#include <asm/gdb-stub.h>
+
+
+static struct atlas_ictrl_regs *atlas_hw0_icregs;
+
+extern asmlinkage void mipsIRQ(void);
+
+#if 0
+#define DEBUG_INT(x...) printk(x)
+#else
+#define DEBUG_INT(x...)
+#endif
+
+void disable_atlas_irq(unsigned int irq_nr)
+{
+ atlas_hw0_icregs->intrsten = (1 << (irq_nr-ATLASINT_BASE));
+ iob();
+}
+
+void enable_atlas_irq(unsigned int irq_nr)
+{
+ atlas_hw0_icregs->intseten = (1 << (irq_nr-ATLASINT_BASE));
+ iob();
+}
+
+static unsigned int startup_atlas_irq(unsigned int irq)
+{
+ enable_atlas_irq(irq);
+ return 0; /* never anything pending */
+}
+
+#define shutdown_atlas_irq disable_atlas_irq
+
+#define mask_and_ack_atlas_irq disable_atlas_irq
+
+static void end_atlas_irq(unsigned int irq)
+{
+ if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+ enable_atlas_irq(irq);
+}
+
+static struct hw_interrupt_type atlas_irq_type = {
+ "Atlas",
+ startup_atlas_irq,
+ shutdown_atlas_irq,
+ enable_atlas_irq,
+ disable_atlas_irq,
+ mask_and_ack_atlas_irq,
+ end_atlas_irq,
+ NULL
+};
+
+static inline int ls1bit32(unsigned int x)
+{
+ int b = 31, s;
+
+ s = 16; if (x << 16 == 0) s = 0; b -= s; x <<= s;
+ s = 8; if (x << 8 == 0) s = 0; b -= s; x <<= s;
+ s = 4; if (x << 4 == 0) s = 0; b -= s; x <<= s;
+ s = 2; if (x << 2 == 0) s = 0; b -= s; x <<= s;
+ s = 1; if (x << 1 == 0) s = 0; b -= s;
+
+ return b;
+}
+
+void atlas_hw0_irqdispatch(struct pt_regs *regs)
+{
+ unsigned long int_status;
+ int irq;
+
+ int_status = atlas_hw0_icregs->intstatus;
+
+ /* if int_status == 0, then the interrupt has already been cleared */
+ if (unlikely(int_status == 0))
+ return;
+
+ irq = ATLASINT_BASE + ls1bit32(int_status);
+
+ DEBUG_INT("atlas_hw0_irqdispatch: irq=%d\n", irq);
+
+ do_IRQ(irq, regs);
+}
+
+void __init arch_init_irq(void)
+{
+ int i;
+
+ atlas_hw0_icregs = (struct atlas_ictrl_regs *)ioremap (ATLAS_ICTRL_REGS_BASE, sizeof(struct atlas_ictrl_regs *));
+
+ /*
+ * Mask out all interrupt by writing "1" to all bit position in
+ * the interrupt reset reg.
+ */
+ atlas_hw0_icregs->intrsten = 0xffffffff;
+
+ /* Now safe to set the exception vector. */
+ set_except_vector(0, mipsIRQ);
+
+ for (i = ATLASINT_BASE; i <= ATLASINT_END; i++) {
+ irq_desc[i].status = IRQ_DISABLED;
+ irq_desc[i].action = 0;
+ irq_desc[i].depth = 1;
+ irq_desc[i].handler = &atlas_irq_type;
+ spin_lock_init(&irq_desc[i].lock);
+ }
+}
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