/* * Carsten Langgaard, carstenl@mips.com * Copyright (C) 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/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/irq.h>#include <asm/mips-boards/atlas.h>#include <asm/mips-boards/atlasint.h>#ifdef CONFIG_REMOTE_DEBUG#include <asm/gdb-stub.h>#endifstruct atlas_ictrl_regs *atlas_hw0_icregs	= (struct atlas_ictrl_regs *)ATLAS_ICTRL_REGS_BASE;extern asmlinkage void mipsIRQ(void);extern void do_IRQ(int irq, struct pt_regs *regs);unsigned long spurious_count = 0;irq_desc_t irq_desc[NR_IRQS];#if 0#define DEBUG_INT(x...) printk(x)#else#define DEBUG_INT(x...)#endifvoid disable_atlas_irq(unsigned int irq_nr){	atlas_hw0_icregs->intrsten = (1 << irq_nr);}void enable_atlas_irq(unsigned int irq_nr){	atlas_hw0_icregs->intseten = (1 << irq_nr);}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_irqstatic 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};int get_irq_list(char *buf){	int i, len = 0;	int num = 0;	struct irqaction *action;	for (i = 0; i < ATLASINT_END; i++, num++) {		action = irq_desc[i].action;		if (!action) 			continue;		len += sprintf(buf+len, "%2d: %8d %c %s",			num, kstat.irqs[0][num],			(action->flags & SA_INTERRUPT) ? '+' : ' ',			action->name);		for (action=action->next; action; action = action->next) {			len += sprintf(buf+len, ",%s %s",				(action->flags & SA_INTERRUPT) ? " +" : "",				action->name);		}		len += sprintf(buf+len, " [hw0]\n");	}	return len;}int request_irq(unsigned int irq, 		void (*handler)(int, void *, struct pt_regs *),		unsigned long irqflags, 		const char * devname,		void *dev_id){          struct irqaction *action;	DEBUG_INT("request_irq: irq=%d, devname = %s\n", irq, devname);        if (irq >= ATLASINT_END)	        return -EINVAL;	if (!handler)	        return -EINVAL;	action = (struct irqaction *)kmalloc(sizeof(struct irqaction), GFP_KERNEL);	if(!action)	        return -ENOMEM;	action->handler = handler;	action->flags = irqflags;	action->mask = 0;	action->name = devname;	action->dev_id = dev_id;	action->next = 0;	irq_desc[irq].action = action;	enable_atlas_irq(irq);	return 0;}void free_irq(unsigned int irq, void *dev_id){	struct irqaction *action;	if (irq >= ATLASINT_END) {		printk("Trying to free IRQ%d\n",irq);		return;	}	action = irq_desc[irq].action;	irq_desc[irq].action = NULL;	disable_atlas_irq(irq);	kfree(action);}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){	struct irqaction *action;	unsigned long int_status;	int irq, cpu = smp_processor_id();	int_status = atlas_hw0_icregs->intstatus; 	/* 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("atlas_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);		spurious_count++;		return;	}	irq_enter(cpu, irq);	kstat.irqs[0][irq]++;	action->handler(irq, action->dev_id, regs);	irq_exit(cpu, irq);	return;		}unsigned long probe_irq_on (void){	return 0;}int probe_irq_off (unsigned long irqs){	return 0;}#ifdef CONFIG_REMOTE_DEBUGextern void breakpoint(void);extern int remote_debug;#endifvoid __init init_IRQ(void){	int i;	/* 	 * 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 = 0; 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;	}#ifdef CONFIG_REMOTE_DEBUG	if (remote_debug) {		set_debug_traps();		breakpoint();	}#endif}