patch-2.4.22 linux-2.4.22/arch/mips/lasat/interrupt.c

• Lines: 193
• Date: 2003-08-25 04:44:40.000000000 -0700
• Orig file: linux-2.4.21/arch/mips/lasat/interrupt.c
• Orig date: 1969-12-31 16:00:00.000000000 -0800

diff -urN linux-2.4.21/arch/mips/lasat/interrupt.c linux-2.4.22/arch/mips/lasat/interrupt.c
@@ -0,0 +1,192 @@
+/*
+ * 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/config.h>
+#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 mipsIRQ(void);
+
+#if 0
+#define DEBUG_INT(x...) printk(x)
+#else
+#define DEBUG_INT(x...)
+#endif
+
+void disable_lasat_irq(unsigned int irq_nr)
+{
+	unsigned long flags;
+	DEBUG_INT("disable_lasat_irq: %d", irq_nr);
+
+	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;
+	DEBUG_INT("enable_lasat_irq: %d", irq_nr);
+
+	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)
+{
+	struct irqaction *action;
+	unsigned long int_status;
+	int irq, cpu = smp_processor_id();
+
+	int_status = get_int_status();
+
+	/* if int_status == 0, then the interrupt has already been cleared */
+	if (int_status == 0)
+		return;
+
+	irq = ls1bit32(int_status);
+	action = irq_desc[irq].action;
+
+	DEBUG_INT("lasat_hw0_irqdispatch: irq=%d\n", irq);
+
+	/* if action == NULL, then we don't have a handler for the irq */
+	if (action == NULL) {
+		printk("No handler for hw0 irq: %i\n", irq);
+		atomic_inc(&irq_err_count);
+		return;
+	}
+
+	irq_enter(cpu, irq);
+	kstat.irqs[0][irq]++;
+	action->handler(irq, action->dev_id, regs);
+	irq_exit(cpu, irq);
+
+	return;		
+}
+
+void __init init_IRQ(void)
+{
+	int i;
+
+	init_generic_irq();
+
+	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("init_IRQ: mips_machtype incorrect");
+	}
+
+	/* Now safe to set the exception vector. */
+	set_except_vector(0, mipsIRQ);
+
+	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;
+	}
+}