summaryrefslogtreecommitdiff
path: root/arch/mips/lasat/interrupt.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/mips/lasat/interrupt.c')
-rw-r--r--arch/mips/lasat/interrupt.c160
1 files changed, 160 insertions, 0 deletions
diff --git a/arch/mips/lasat/interrupt.c b/arch/mips/lasat/interrupt.c
new file mode 100644
index 00000000000..1148a2d20aa
--- /dev/null
+++ b/arch/mips/lasat/interrupt.c
@@ -0,0 +1,160 @@
+/*
+ * 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
+ * Lasat boards.
+ */
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+
+#include <asm/bootinfo.h>
+#include <asm/irq.h>
+#include <asm/lasat/lasatint.h>
+#include <asm/gdb-stub.h>
+
+static volatile int *lasat_int_status = NULL;
+static volatile int *lasat_int_mask = NULL;
+static volatile int lasat_int_mask_shift;
+
+extern asmlinkage void lasatIRQ(void);
+
+void disable_lasat_irq(unsigned int irq_nr)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ *lasat_int_mask &= ~(1 << irq_nr) << lasat_int_mask_shift;
+ local_irq_restore(flags);
+}
+
+void enable_lasat_irq(unsigned int irq_nr)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ *lasat_int_mask |= (1 << irq_nr) << lasat_int_mask_shift;
+ local_irq_restore(flags);
+}
+
+static unsigned int startup_lasat_irq(unsigned int irq)
+{
+ enable_lasat_irq(irq);
+
+ return 0; /* never anything pending */
+}
+
+#define shutdown_lasat_irq disable_lasat_irq
+
+#define mask_and_ack_lasat_irq disable_lasat_irq
+
+static void end_lasat_irq(unsigned int irq)
+{
+ if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+ enable_lasat_irq(irq);
+}
+
+static struct hw_interrupt_type lasat_irq_type = {
+ "Lasat",
+ startup_lasat_irq,
+ shutdown_lasat_irq,
+ enable_lasat_irq,
+ disable_lasat_irq,
+ mask_and_ack_lasat_irq,
+ end_lasat_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;
+}
+
+static unsigned long (* get_int_status)(void);
+
+static unsigned long get_int_status_100(void)
+{
+ return *lasat_int_status & *lasat_int_mask;
+}
+
+static unsigned long get_int_status_200(void)
+{
+ unsigned long int_status;
+
+ int_status = *lasat_int_status;
+ int_status &= (int_status >> LASATINT_MASK_SHIFT_200) & 0xffff;
+ return int_status;
+}
+
+void lasat_hw0_irqdispatch(struct pt_regs *regs)
+{
+ unsigned long int_status;
+ int irq;
+
+ int_status = get_int_status();
+
+ /* if int_status == 0, then the interrupt has already been cleared */
+ if (int_status) {
+ irq = ls1bit32(int_status);
+
+ do_IRQ(irq, regs);
+ }
+}
+
+void __init arch_init_irq(void)
+{
+ int i;
+
+ switch (mips_machtype) {
+ case MACH_LASAT_100:
+ lasat_int_status = (void *)LASAT_INT_STATUS_REG_100;
+ lasat_int_mask = (void *)LASAT_INT_MASK_REG_100;
+ lasat_int_mask_shift = LASATINT_MASK_SHIFT_100;
+ get_int_status = get_int_status_100;
+ *lasat_int_mask = 0;
+ break;
+ case MACH_LASAT_200:
+ lasat_int_status = (void *)LASAT_INT_STATUS_REG_200;
+ lasat_int_mask = (void *)LASAT_INT_MASK_REG_200;
+ lasat_int_mask_shift = LASATINT_MASK_SHIFT_200;
+ get_int_status = get_int_status_200;
+ *lasat_int_mask &= 0xffff;
+ break;
+ default:
+ panic("arch_init_irq: mips_machtype incorrect");
+ }
+
+ /* Now safe to set the exception vector. */
+ set_except_vector(0, lasatIRQ);
+
+ for (i = 0; i <= LASATINT_END; i++) {
+ irq_desc[i].status = IRQ_DISABLED;
+ irq_desc[i].action = 0;
+ irq_desc[i].depth = 1;
+ irq_desc[i].handler = &lasat_irq_type;
+ }
+}