arch/sparc/kernel/sun4d_irq.c - arm/linux-arm64-legacy - Git at Google

 /*
  *  arch/sparc/kernel/sun4d_irq.c:
  *			SS1000/SC2000 interrupt handling.
  *
  *  Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
  *  Heavily based on arch/sparc/kernel/irq.c.
  */

 #include <linux/errno.h>
 #include <linux/linkage.h>
 #include <linux/kernel_stat.h>
 #include <linux/signal.h>
 #include <linux/sched.h>
 #include <linux/ptrace.h>
 #include <linux/interrupt.h>
 #include <linux/slab.h>
 #include <linux/random.h>
 #include <linux/init.h>
 #include <linux/smp.h>
 #include <linux/spinlock.h>
 #include <linux/seq_file.h>

 #include <asm/ptrace.h>
 #include <asm/processor.h>
 #include <asm/system.h>
 #include <asm/psr.h>
 #include <asm/smp.h>
 #include <asm/vaddrs.h>
 #include <asm/timer.h>
 #include <asm/openprom.h>
 #include <asm/oplib.h>
 #include <asm/traps.h>
 #include <asm/irq.h>
 #include <asm/io.h>
 #include <asm/pgalloc.h>
 #include <asm/pgtable.h>
 #include <asm/sbus.h>
 #include <asm/sbi.h>
 #include <asm/cacheflush.h>
 #include <asm/irq_regs.h>

 #include "irq.h"

 /* If you trust current SCSI layer to handle different SCSI IRQs, enable this. I don't trust it... -jj */
 /* #define DISTRIBUTE_IRQS */

 struct sun4d_timer_regs *sun4d_timers;
 #define TIMER_IRQ	10

 #define MAX_STATIC_ALLOC	4
 extern struct irqaction static_irqaction[MAX_STATIC_ALLOC];
 extern int static_irq_count;
 unsigned char cpu_leds[32];
 #ifdef CONFIG_SMP
 static unsigned char sbus_tid[32];
 #endif

 static struct irqaction *irq_action[NR_IRQS];
 extern spinlock_t irq_action_lock;

 static struct sbus_action {
 	struct irqaction *action;
 	/* For SMP this needs to be extended */
 } *sbus_actions;

 static int pil_to_sbus[] = {
 	0, 0, 1, 2, 0, 3, 0, 4, 0, 5, 0, 6, 0, 7, 0, 0,
 };

 static int sbus_to_pil[] = {
 	0, 2, 3, 5, 7, 9, 11, 13,
 };

 static int nsbi;
 #ifdef CONFIG_SMP
 DEFINE_SPINLOCK(sun4d_imsk_lock);
 #endif

 int show_sun4d_interrupts(struct seq_file *p, void *v)
 {
 	int i = *(loff_t *) v, j = 0, k = 0, sbusl;
 	struct irqaction * action;
 	unsigned long flags;
 #ifdef CONFIG_SMP
 	int x;
 #endif

 	spin_lock_irqsave(&irq_action_lock, flags);
 	if (i < NR_IRQS) {
 		sbusl = pil_to_sbus[i];
 		if (!sbusl) {
 	 		action = *(i + irq_action);
 			if (!action)
 		        	goto out_unlock;
 		} else {
 			for (j = 0; j < nsbi; j++) {
 				for (k = 0; k < 4; k++)
 					if ((action = sbus_actions [(j << 5) + (sbusl << 2) + k].action))
 						goto found_it;
 			}
 			goto out_unlock;
 		}
 found_it:	seq_printf(p, "%3d: ", i);
 #ifndef CONFIG_SMP
 		seq_printf(p, "%10u ", kstat_irqs(i));
 #else
 		for_each_online_cpu(x)
 			seq_printf(p, "%10u ",
 			       kstat_cpu(cpu_logical_map(x)).irqs[i]);
 #endif
 		seq_printf(p, "%c %s",
 			(action->flags & IRQF_DISABLED) ? '+' : ' ',
 			action->name);
 		action = action->next;
 		for (;;) {
 			for (; action; action = action->next) {
 				seq_printf(p, ",%s %s",
 					(action->flags & IRQF_DISABLED) ? " +" : "",
 					action->name);
 			}
 			if (!sbusl) break;
 			k++;
 			if (k < 4)
 				action = sbus_actions [(j << 5) + (sbusl << 2) + k].action;
 			else {
 				j++;
 				if (j == nsbi) break;
 				k = 0;
 				action = sbus_actions [(j << 5) + (sbusl << 2)].action;
 			}
 		}
 		seq_putc(p, '\n');
 	}
 out_unlock:
 	spin_unlock_irqrestore(&irq_action_lock, flags);
 	return 0;
 }

 void sun4d_free_irq(unsigned int irq, void *dev_id)
 {
 	struct irqaction *action, **actionp;
 	struct irqaction *tmp = NULL;
         unsigned long flags;

 	spin_lock_irqsave(&irq_action_lock, flags);
 	if (irq < 15)
 		actionp = irq + irq_action;
 	else
 		actionp = &(sbus_actions[irq - (1 << 5)].action);
 	action = *actionp;
 	if (!action) {
 		printk("Trying to free free IRQ%d\n",irq);
 		goto out_unlock;
 	}
 	if (dev_id) {
 		for (; action; action = action->next) {
 			if (action->dev_id == dev_id)
 				break;
 			tmp = action;
 		}
 		if (!action) {
 			printk("Trying to free free shared IRQ%d\n",irq);
 			goto out_unlock;
 		}
 	} else if (action->flags & IRQF_SHARED) {
 		printk("Trying to free shared IRQ%d with NULL device ID\n", irq);
 		goto out_unlock;
 	}
 	if (action->flags & SA_STATIC_ALLOC)
 	{
 		/* This interrupt is marked as specially allocated
 		 * so it is a bad idea to free it.
 		 */
 		printk("Attempt to free statically allocated IRQ%d (%s)\n",
 		       irq, action->name);
 		goto out_unlock;
 	}

 	if (action && tmp)
 		tmp->next = action->next;
 	else
 		*actionp = action->next;

 	spin_unlock_irqrestore(&irq_action_lock, flags);

 	synchronize_irq(irq);

 	spin_lock_irqsave(&irq_action_lock, flags);

 	kfree(action);

 	if (!(*actionp))
 		__disable_irq(irq);

 out_unlock:
 	spin_unlock_irqrestore(&irq_action_lock, flags);
 }

 extern void unexpected_irq(int, void *, struct pt_regs *);

 void sun4d_handler_irq(int irq, struct pt_regs * regs)
 {
 	struct pt_regs *old_regs;
 	struct irqaction * action;
 	int cpu = smp_processor_id();
 	/* SBUS IRQ level (1 - 7) */
 	int sbusl = pil_to_sbus[irq];

 	/* FIXME: Is this necessary?? */
 	cc_get_ipen();

 	cc_set_iclr(1 << irq);

 	old_regs = set_irq_regs(regs);
 	irq_enter();
 	kstat_cpu(cpu).irqs[irq]++;
 	if (!sbusl) {
 		action = *(irq + irq_action);
 		if (!action)
 			unexpected_irq(irq, NULL, regs);
 		do {
 			action->handler(irq, action->dev_id);
 			action = action->next;
 		} while (action);
 	} else {
 		int bus_mask = bw_get_intr_mask(sbusl) & 0x3ffff;
 		int sbino;
 		struct sbus_action *actionp;
 		unsigned mask, slot;
 		int sbil = (sbusl << 2);

 		bw_clear_intr_mask(sbusl, bus_mask);

 		/* Loop for each pending SBI */
 		for (sbino = 0; bus_mask; sbino++, bus_mask >>= 1)
 			if (bus_mask & 1) {
 				mask = acquire_sbi(SBI2DEVID(sbino), 0xf << sbil);
 				mask &= (0xf << sbil);
 				actionp = sbus_actions + (sbino << 5) + (sbil);
 				/* Loop for each pending SBI slot */
 				for (slot = (1 << sbil); mask; slot <<= 1, actionp++)
 					if (mask & slot) {
 						mask &= ~slot;
 						action = actionp->action;

 						if (!action)
 							unexpected_irq(irq, NULL, regs);
 						do {
 							action->handler(irq, action->dev_id);
 							action = action->next;
 						} while (action);
 						release_sbi(SBI2DEVID(sbino), slot);
 					}
 			}
 	}
 	irq_exit();
 	set_irq_regs(old_regs);
 }

 int sun4d_request_irq(unsigned int irq,
 		irq_handler_t handler,
 		unsigned long irqflags, const char * devname, void *dev_id)
 {
 	struct irqaction *action, *tmp = NULL, **actionp;
 	unsigned long flags;
 	int ret;

 	if(irq > 14 && irq < (1 << 5)) {
 		ret = -EINVAL;
 		goto out;
 	}

 	if (!handler) {
 		ret = -EINVAL;
 		goto out;
 	}

 	spin_lock_irqsave(&irq_action_lock, flags);

 	if (irq >= (1 << 5))
 		actionp = &(sbus_actions[irq - (1 << 5)].action);
 	else
 		actionp = irq + irq_action;
 	action = *actionp;

 	if (action) {
 		if ((action->flags & IRQF_SHARED) && (irqflags & IRQF_SHARED)) {
 			for (tmp = action; tmp->next; tmp = tmp->next);
 		} else {
 			ret = -EBUSY;
 			goto out_unlock;
 		}
 		if ((action->flags & IRQF_DISABLED) ^ (irqflags & IRQF_DISABLED)) {
 			printk("Attempt to mix fast and slow interrupts on IRQ%d denied\n", irq);
 			ret = -EBUSY;
 			goto out_unlock;
 		}
 		action = NULL;		/* Or else! */
 	}

 	/* If this is flagged as statically allocated then we use our
 	 * private struct which is never freed.
 	 */
 	if (irqflags & SA_STATIC_ALLOC) {
 		if (static_irq_count < MAX_STATIC_ALLOC)
 			action = &static_irqaction[static_irq_count++];
 		else
 			printk("Request for IRQ%d (%s) SA_STATIC_ALLOC failed using kmalloc\n", irq, devname);
 	}

 	if (action == NULL)
 		action = kmalloc(sizeof(struct irqaction),
 						     GFP_ATOMIC);

 	if (!action) {
 		ret = -ENOMEM;
 		goto out_unlock;
 	}

 	action->handler = handler;
 	action->flags = irqflags;
 	cpus_clear(action->mask);
 	action->name = devname;
 	action->next = NULL;
 	action->dev_id = dev_id;

 	if (tmp)
 		tmp->next = action;
 	else
 		*actionp = action;

 	__enable_irq(irq);

 	ret = 0;
 out_unlock:
 	spin_unlock_irqrestore(&irq_action_lock, flags);
 out:
 	return ret;
 }

 static void sun4d_disable_irq(unsigned int irq)
 {
 #ifdef CONFIG_SMP
 	int tid = sbus_tid[(irq >> 5) - 1];
 	unsigned long flags;
 #endif

 	if (irq < NR_IRQS) return;
 #ifdef CONFIG_SMP
 	spin_lock_irqsave(&sun4d_imsk_lock, flags);
 	cc_set_imsk_other(tid, cc_get_imsk_other(tid) | (1 << sbus_to_pil[(irq >> 2) & 7]));
 	spin_unlock_irqrestore(&sun4d_imsk_lock, flags);
 #else
 	cc_set_imsk(cc_get_imsk() | (1 << sbus_to_pil[(irq >> 2) & 7]));
 #endif
 }

 static void sun4d_enable_irq(unsigned int irq)
 {
 #ifdef CONFIG_SMP
 	int tid = sbus_tid[(irq >> 5) - 1];
 	unsigned long flags;
 #endif

 	if (irq < NR_IRQS) return;
 #ifdef CONFIG_SMP
 	spin_lock_irqsave(&sun4d_imsk_lock, flags);
 	cc_set_imsk_other(tid, cc_get_imsk_other(tid) & ~(1 << sbus_to_pil[(irq >> 2) & 7]));
 	spin_unlock_irqrestore(&sun4d_imsk_lock, flags);
 #else
 	cc_set_imsk(cc_get_imsk() & ~(1 << sbus_to_pil[(irq >> 2) & 7]));
 #endif
 }

 #ifdef CONFIG_SMP
 static void sun4d_set_cpu_int(int cpu, int level)
 {
 	sun4d_send_ipi(cpu, level);
 }

 static void sun4d_clear_ipi(int cpu, int level)
 {
 }

 static void sun4d_set_udt(int cpu)
 {
 }

 /* Setup IRQ distribution scheme. */
 void __init sun4d_distribute_irqs(void)
 {
 	struct device_node *dp;

 #ifdef DISTRIBUTE_IRQS
 	cpumask_t sbus_serving_map;

 	sbus_serving_map = cpu_present_map;
 	for_each_node_by_name(dp, "sbi") {
 		int board = of_getintprop_default(dp, "board#", 0);

 		if ((board * 2) == boot_cpu_id && cpu_isset(board * 2 + 1, cpu_present_map))
 			sbus_tid[board] = (board * 2 + 1);
 		else if (cpu_isset(board * 2, cpu_present_map))
 			sbus_tid[board] = (board * 2);
 		else if (cpu_isset(board * 2 + 1, cpu_present_map))
 			sbus_tid[board] = (board * 2 + 1);
 		else
 			sbus_tid[board] = 0xff;
 		if (sbus_tid[board] != 0xff)
 			cpu_clear(sbus_tid[board], sbus_serving_map);
 	}
 	for_each_node_by_name(dp, "sbi") {
 		int board = of_getintprop_default(dp, "board#", 0);
 		if (sbus_tid[board] == 0xff) {
 			int i = 31;

 			if (cpus_empty(sbus_serving_map))
 				sbus_serving_map = cpu_present_map;
 			while (cpu_isset(i, sbus_serving_map))
 				i--;
 			sbus_tid[board] = i;
 			cpu_clear(i, sbus_serving_map);
 		}
 	}
 	for_each_node_by_name(dp, "sbi") {
 		int devid = of_getintprop_default(dp, "device-id", 0);
 		int board = of_getintprop_default(dp, "board#", 0);
 		printk("sbus%d IRQs directed to CPU%d\n", board, sbus_tid[board]);
 		set_sbi_tid(devid, sbus_tid[board] << 3);
 	}
 #else
 	int cpuid = cpu_logical_map(1);

 	if (cpuid == -1)
 		cpuid = cpu_logical_map(0);
 	for_each_node_by_name(dp, "sbi") {
 		int devid = of_getintprop_default(dp, "device-id", 0);
 		int board = of_getintprop_default(dp, "board#", 0);
 		sbus_tid[board] = cpuid;
 		set_sbi_tid(devid, cpuid << 3);
 	}
 	printk("All sbus IRQs directed to CPU%d\n", cpuid);
 #endif
 }
 #endif

 static void sun4d_clear_clock_irq(void)
 {
 	volatile unsigned int clear_intr;
 	clear_intr = sun4d_timers->l10_timer_limit;
 }

 static void sun4d_clear_profile_irq(int cpu)
 {
 	bw_get_prof_limit(cpu);
 }

 static void sun4d_load_profile_irq(int cpu, unsigned int limit)
 {
 	bw_set_prof_limit(cpu, limit);
 }

 static void __init sun4d_init_timers(irq_handler_t counter_fn)
 {
 	int irq;
 	int cpu;
 	struct resource r;
 	int mid;

 	/* Map the User Timer registers. */
 	memset(&r, 0, sizeof(r));
 #ifdef CONFIG_SMP
 	r.start = CSR_BASE(boot_cpu_id)+BW_TIMER_LIMIT;
 #else
 	r.start = CSR_BASE(0)+BW_TIMER_LIMIT;
 #endif
 	r.flags = 0xf;
 	sun4d_timers = (struct sun4d_timer_regs *) sbus_ioremap(&r, 0,
 	    PAGE_SIZE, "user timer");

 	sun4d_timers->l10_timer_limit =  (((1000000/HZ) + 1) << 10);
 	master_l10_counter = &sun4d_timers->l10_cur_count;
 	master_l10_limit = &sun4d_timers->l10_timer_limit;

 	irq = request_irq(TIMER_IRQ,
 			  counter_fn,
 			  (IRQF_DISABLED | SA_STATIC_ALLOC),
 			  "timer", NULL);
 	if (irq) {
 		prom_printf("time_init: unable to attach IRQ%d\n",TIMER_IRQ);
 		prom_halt();
 	}

 	/* Enable user timer free run for CPU 0 in BW */
 	/* bw_set_ctrl(0, bw_get_ctrl(0) | BW_CTRL_USER_TIMER); */

 	cpu = 0;
 	while (!cpu_find_by_instance(cpu, NULL, &mid)) {
 		sun4d_load_profile_irq(mid >> 3, 0);
 		cpu++;
 	}

 #ifdef CONFIG_SMP
 	{
 		unsigned long flags;
 		extern unsigned long lvl14_save[4];
 		struct tt_entry *trap_table = &sparc_ttable[SP_TRAP_IRQ1 + (14 - 1)];
 		extern unsigned int real_irq_entry[], smp4d_ticker[];
 		extern unsigned int patchme_maybe_smp_msg[];

 		/* Adjust so that we jump directly to smp4d_ticker */
 		lvl14_save[2] += smp4d_ticker - real_irq_entry;

 		/* For SMP we use the level 14 ticker, however the bootup code
 		 * has copied the firmware's level 14 vector into the boot cpu's
 		 * trap table, we must fix this now or we get squashed.
 		 */
 		local_irq_save(flags);
 		patchme_maybe_smp_msg[0] = 0x01000000; /* NOP out the branch */
 		trap_table->inst_one = lvl14_save[0];
 		trap_table->inst_two = lvl14_save[1];
 		trap_table->inst_three = lvl14_save[2];
 		trap_table->inst_four = lvl14_save[3];
 		local_flush_cache_all();
 		local_irq_restore(flags);
 	}
 #endif
 }

 void __init sun4d_init_sbi_irq(void)
 {
 	struct device_node *dp;

 	nsbi = 0;
 	for_each_node_by_name(dp, "sbi")
 		nsbi++;
 	sbus_actions = kzalloc (nsbi * 8 * 4 * sizeof(struct sbus_action), GFP_ATOMIC);
 	if (!sbus_actions) {
 		prom_printf("SUN4D: Cannot allocate sbus_actions, halting.\n");
 		prom_halt();
 	}
 	for_each_node_by_name(dp, "sbi") {
 		int devid = of_getintprop_default(dp, "device-id", 0);
 		int board = of_getintprop_default(dp, "board#", 0);
 		unsigned int mask;

 #ifdef CONFIG_SMP
 		{
 			extern unsigned char boot_cpu_id;

 			set_sbi_tid(devid, boot_cpu_id << 3);
 			sbus_tid[board] = boot_cpu_id;
 		}
 #endif
 		/* Get rid of pending irqs from PROM */
 		mask = acquire_sbi(devid, 0xffffffff);
 		if (mask) {
 			printk ("Clearing pending IRQs %08x on SBI %d\n", mask, board);
 			release_sbi(devid, mask);
 		}
 	}
 }

 void __init sun4d_init_IRQ(void)
 {
 	local_irq_disable();

 	BTFIXUPSET_CALL(enable_irq, sun4d_enable_irq, BTFIXUPCALL_NORM);
 	BTFIXUPSET_CALL(disable_irq, sun4d_disable_irq, BTFIXUPCALL_NORM);
 	BTFIXUPSET_CALL(clear_clock_irq, sun4d_clear_clock_irq, BTFIXUPCALL_NORM);
 	BTFIXUPSET_CALL(clear_profile_irq, sun4d_clear_profile_irq, BTFIXUPCALL_NORM);
 	BTFIXUPSET_CALL(load_profile_irq, sun4d_load_profile_irq, BTFIXUPCALL_NORM);
 	sparc_init_timers = sun4d_init_timers;
 #ifdef CONFIG_SMP
 	BTFIXUPSET_CALL(set_cpu_int, sun4d_set_cpu_int, BTFIXUPCALL_NORM);
 	BTFIXUPSET_CALL(clear_cpu_int, sun4d_clear_ipi, BTFIXUPCALL_NOP);
 	BTFIXUPSET_CALL(set_irq_udt, sun4d_set_udt, BTFIXUPCALL_NOP);
 #endif
 	/* Cannot enable interrupts until OBP ticker is disabled. */
 }
	/*
	* arch/sparc/kernel/sun4d_irq.c:
	* SS1000/SC2000 interrupt handling.
	*
	* Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
	* Heavily based on arch/sparc/kernel/irq.c.
	*/

	#include <linux/errno.h>
	#include <linux/linkage.h>
	#include <linux/kernel_stat.h>
	#include <linux/signal.h>
	#include <linux/sched.h>
	#include <linux/ptrace.h>
	#include <linux/interrupt.h>
	#include <linux/slab.h>
	#include <linux/random.h>
	#include <linux/init.h>
	#include <linux/smp.h>
	#include <linux/spinlock.h>
	#include <linux/seq_file.h>

	#include <asm/ptrace.h>
	#include <asm/processor.h>
	#include <asm/system.h>
	#include <asm/psr.h>
	#include <asm/smp.h>
	#include <asm/vaddrs.h>
	#include <asm/timer.h>
	#include <asm/openprom.h>
	#include <asm/oplib.h>
	#include <asm/traps.h>
	#include <asm/irq.h>
	#include <asm/io.h>
	#include <asm/pgalloc.h>
	#include <asm/pgtable.h>
	#include <asm/sbus.h>
	#include <asm/sbi.h>
	#include <asm/cacheflush.h>
	#include <asm/irq_regs.h>

	#include "irq.h"

	/* If you trust current SCSI layer to handle different SCSI IRQs, enable this. I don't trust it... -jj */
	/* #define DISTRIBUTE_IRQS */

	struct sun4d_timer_regs *sun4d_timers;
	#define TIMER_IRQ 10

	#define MAX_STATIC_ALLOC 4
	extern struct irqaction static_irqaction[MAX_STATIC_ALLOC];
	extern int static_irq_count;
	unsigned char cpu_leds[32];
	#ifdef CONFIG_SMP
	static unsigned char sbus_tid[32];
	#endif

	static struct irqaction *irq_action[NR_IRQS];
	extern spinlock_t irq_action_lock;

	static struct sbus_action {
	struct irqaction *action;
	/* For SMP this needs to be extended */
	} *sbus_actions;

	static int pil_to_sbus[] = {
	0, 0, 1, 2, 0, 3, 0, 4, 0, 5, 0, 6, 0, 7, 0, 0,
	};

	static int sbus_to_pil[] = {
	0, 2, 3, 5, 7, 9, 11, 13,
	};

	static int nsbi;
	#ifdef CONFIG_SMP
	DEFINE_SPINLOCK(sun4d_imsk_lock);
	#endif

	int show_sun4d_interrupts(struct seq_file p, void v)
	{
	int i = (loff_t ) v, j = 0, k = 0, sbusl;
	struct irqaction * action;
	unsigned long flags;
	#ifdef CONFIG_SMP
	int x;
	#endif

	spin_lock_irqsave(&irq_action_lock, flags);
	if (i < NR_IRQS) {
	sbusl = pil_to_sbus[i];
	if (!sbusl) {
	action = *(i + irq_action);
	if (!action)
	goto out_unlock;
	} else {
	for (j = 0; j < nsbi; j++) {
	for (k = 0; k < 4; k++)
	if ((action = sbus_actions [(j << 5) + (sbusl << 2) + k].action))
	goto found_it;
	}
	goto out_unlock;
	}
	found_it: seq_printf(p, "%3d: ", i);
	#ifndef CONFIG_SMP
	seq_printf(p, "%10u ", kstat_irqs(i));
	#else
	for_each_online_cpu(x)
	seq_printf(p, "%10u ",
	kstat_cpu(cpu_logical_map(x)).irqs[i]);
	#endif
	seq_printf(p, "%c %s",
	(action->flags & IRQF_DISABLED) ? '+' : ' ',
	action->name);
	action = action->next;
	for (;;) {
	for (; action; action = action->next) {
	seq_printf(p, ",%s %s",
	(action->flags & IRQF_DISABLED) ? " +" : "",
	action->name);
	}
	if (!sbusl) break;
	k++;
	if (k < 4)
	action = sbus_actions [(j << 5) + (sbusl << 2) + k].action;
	else {
	j++;
	if (j == nsbi) break;
	k = 0;
	action = sbus_actions [(j << 5) + (sbusl << 2)].action;
	}
	}
	seq_putc(p, '\n');
	}
	out_unlock:
	spin_unlock_irqrestore(&irq_action_lock, flags);
	return 0;
	}

	void sun4d_free_irq(unsigned int irq, void *dev_id)
	{
	struct irqaction action, *actionp;
	struct irqaction *tmp = NULL;
	unsigned long flags;

	spin_lock_irqsave(&irq_action_lock, flags);
	if (irq < 15)
	actionp = irq + irq_action;
	else
	actionp = &(sbus_actions[irq - (1 << 5)].action);
	action = *actionp;
	if (!action) {
	printk("Trying to free free IRQ%d\n",irq);
	goto out_unlock;
	}
	if (dev_id) {
	for (; action; action = action->next) {
	if (action->dev_id == dev_id)
	break;
	tmp = action;
	}
	if (!action) {
	printk("Trying to free free shared IRQ%d\n",irq);
	goto out_unlock;
	}
	} else if (action->flags & IRQF_SHARED) {
	printk("Trying to free shared IRQ%d with NULL device ID\n", irq);
	goto out_unlock;
	}
	if (action->flags & SA_STATIC_ALLOC)
	{
	/* This interrupt is marked as specially allocated
	* so it is a bad idea to free it.
	*/
	printk("Attempt to free statically allocated IRQ%d (%s)\n",
	irq, action->name);
	goto out_unlock;
	}

	if (action && tmp)
	tmp->next = action->next;
	else
	*actionp = action->next;

	spin_unlock_irqrestore(&irq_action_lock, flags);

	synchronize_irq(irq);

	spin_lock_irqsave(&irq_action_lock, flags);

	kfree(action);

	if (!(*actionp))
	__disable_irq(irq);

	out_unlock:
	spin_unlock_irqrestore(&irq_action_lock, flags);
	}

	extern void unexpected_irq(int, void , struct pt_regs );

	void sun4d_handler_irq(int irq, struct pt_regs * regs)
	{
	struct pt_regs *old_regs;
	struct irqaction * action;
	int cpu = smp_processor_id();
	/* SBUS IRQ level (1 - 7) */
	int sbusl = pil_to_sbus[irq];

	/* FIXME: Is this necessary?? */
	cc_get_ipen();

	cc_set_iclr(1 << irq);

	old_regs = set_irq_regs(regs);
	irq_enter();
	kstat_cpu(cpu).irqs[irq]++;
	if (!sbusl) {
	action = *(irq + irq_action);
	if (!action)
	unexpected_irq(irq, NULL, regs);
	do {
	action->handler(irq, action->dev_id);
	action = action->next;
	} while (action);
	} else {
	int bus_mask = bw_get_intr_mask(sbusl) & 0x3ffff;
	int sbino;
	struct sbus_action *actionp;
	unsigned mask, slot;
	int sbil = (sbusl << 2);

	bw_clear_intr_mask(sbusl, bus_mask);

	/* Loop for each pending SBI */
	for (sbino = 0; bus_mask; sbino++, bus_mask >>= 1)
	if (bus_mask & 1) {
	mask = acquire_sbi(SBI2DEVID(sbino), 0xf << sbil);
	mask &= (0xf << sbil);
	actionp = sbus_actions + (sbino << 5) + (sbil);
	/* Loop for each pending SBI slot */
	for (slot = (1 << sbil); mask; slot <<= 1, actionp++)
	if (mask & slot) {
	mask &= ~slot;
	action = actionp->action;

	if (!action)
	unexpected_irq(irq, NULL, regs);
	do {
	action->handler(irq, action->dev_id);
	action = action->next;
	} while (action);
	release_sbi(SBI2DEVID(sbino), slot);
	}
	}
	}
	irq_exit();
	set_irq_regs(old_regs);
	}

	int sun4d_request_irq(unsigned int irq,
	irq_handler_t handler,
	unsigned long irqflags, const char * devname, void *dev_id)
	{
	struct irqaction action, tmp = NULL, **actionp;
	unsigned long flags;
	int ret;

	if(irq > 14 && irq < (1 << 5)) {
	ret = -EINVAL;
	goto out;
	}

	if (!handler) {
	ret = -EINVAL;
	goto out;
	}

	spin_lock_irqsave(&irq_action_lock, flags);

	if (irq >= (1 << 5))
	actionp = &(sbus_actions[irq - (1 << 5)].action);
	else
	actionp = irq + irq_action;
	action = *actionp;

	if (action) {
	if ((action->flags & IRQF_SHARED) && (irqflags & IRQF_SHARED)) {
	for (tmp = action; tmp->next; tmp = tmp->next);
	} else {
	ret = -EBUSY;
	goto out_unlock;
	}
	if ((action->flags & IRQF_DISABLED) ^ (irqflags & IRQF_DISABLED)) {
	printk("Attempt to mix fast and slow interrupts on IRQ%d denied\n", irq);
	ret = -EBUSY;
	goto out_unlock;
	}
	action = NULL; /* Or else! */
	}

	/* If this is flagged as statically allocated then we use our
	* private struct which is never freed.
	*/
	if (irqflags & SA_STATIC_ALLOC) {
	if (static_irq_count < MAX_STATIC_ALLOC)
	action = &static_irqaction[static_irq_count++];
	else
	printk("Request for IRQ%d (%s) SA_STATIC_ALLOC failed using kmalloc\n", irq, devname);
	}

	if (action == NULL)
	action = kmalloc(sizeof(struct irqaction),
	GFP_ATOMIC);

	if (!action) {
	ret = -ENOMEM;
	goto out_unlock;
	}

	action->handler = handler;
	action->flags = irqflags;
	cpus_clear(action->mask);
	action->name = devname;
	action->next = NULL;
	action->dev_id = dev_id;

	if (tmp)
	tmp->next = action;
	else
	*actionp = action;

	__enable_irq(irq);

	ret = 0;
	out_unlock:
	spin_unlock_irqrestore(&irq_action_lock, flags);
	out:
	return ret;
	}

	static void sun4d_disable_irq(unsigned int irq)
	{
	#ifdef CONFIG_SMP
	int tid = sbus_tid[(irq >> 5) - 1];
	unsigned long flags;
	#endif

	if (irq < NR_IRQS) return;
	#ifdef CONFIG_SMP
	spin_lock_irqsave(&sun4d_imsk_lock, flags);
	cc_set_imsk_other(tid, cc_get_imsk_other(tid) \| (1 << sbus_to_pil[(irq >> 2) & 7]));
	spin_unlock_irqrestore(&sun4d_imsk_lock, flags);
	#else
	cc_set_imsk(cc_get_imsk() \| (1 << sbus_to_pil[(irq >> 2) & 7]));
	#endif
	}

	static void sun4d_enable_irq(unsigned int irq)
	{
	#ifdef CONFIG_SMP
	int tid = sbus_tid[(irq >> 5) - 1];
	unsigned long flags;
	#endif

	if (irq < NR_IRQS) return;
	#ifdef CONFIG_SMP
	spin_lock_irqsave(&sun4d_imsk_lock, flags);
	cc_set_imsk_other(tid, cc_get_imsk_other(tid) & ~(1 << sbus_to_pil[(irq >> 2) & 7]));
	spin_unlock_irqrestore(&sun4d_imsk_lock, flags);
	#else
	cc_set_imsk(cc_get_imsk() & ~(1 << sbus_to_pil[(irq >> 2) & 7]));
	#endif
	}

	#ifdef CONFIG_SMP
	static void sun4d_set_cpu_int(int cpu, int level)
	{
	sun4d_send_ipi(cpu, level);
	}

	static void sun4d_clear_ipi(int cpu, int level)
	{
	}

	static void sun4d_set_udt(int cpu)
	{
	}

	/* Setup IRQ distribution scheme. */
	void __init sun4d_distribute_irqs(void)
	{
	struct device_node *dp;

	#ifdef DISTRIBUTE_IRQS
	cpumask_t sbus_serving_map;

	sbus_serving_map = cpu_present_map;
	for_each_node_by_name(dp, "sbi") {
	int board = of_getintprop_default(dp, "board#", 0);

	if ((board * 2) == boot_cpu_id && cpu_isset(board * 2 + 1, cpu_present_map))
	sbus_tid[board] = (board * 2 + 1);
	else if (cpu_isset(board * 2, cpu_present_map))
	sbus_tid[board] = (board * 2);
	else if (cpu_isset(board * 2 + 1, cpu_present_map))
	sbus_tid[board] = (board * 2 + 1);
	else
	sbus_tid[board] = 0xff;
	if (sbus_tid[board] != 0xff)
	cpu_clear(sbus_tid[board], sbus_serving_map);
	}
	for_each_node_by_name(dp, "sbi") {
	int board = of_getintprop_default(dp, "board#", 0);
	if (sbus_tid[board] == 0xff) {
	int i = 31;

	if (cpus_empty(sbus_serving_map))
	sbus_serving_map = cpu_present_map;
	while (cpu_isset(i, sbus_serving_map))
	i--;
	sbus_tid[board] = i;
	cpu_clear(i, sbus_serving_map);
	}
	}
	for_each_node_by_name(dp, "sbi") {
	int devid = of_getintprop_default(dp, "device-id", 0);
	int board = of_getintprop_default(dp, "board#", 0);
	printk("sbus%d IRQs directed to CPU%d\n", board, sbus_tid[board]);
	set_sbi_tid(devid, sbus_tid[board] << 3);
	}
	#else
	int cpuid = cpu_logical_map(1);

	if (cpuid == -1)
	cpuid = cpu_logical_map(0);
	for_each_node_by_name(dp, "sbi") {
	int devid = of_getintprop_default(dp, "device-id", 0);
	int board = of_getintprop_default(dp, "board#", 0);
	sbus_tid[board] = cpuid;
	set_sbi_tid(devid, cpuid << 3);
	}
	printk("All sbus IRQs directed to CPU%d\n", cpuid);
	#endif
	}
	#endif

	static void sun4d_clear_clock_irq(void)
	{
	volatile unsigned int clear_intr;
	clear_intr = sun4d_timers->l10_timer_limit;
	}

	static void sun4d_clear_profile_irq(int cpu)
	{
	bw_get_prof_limit(cpu);
	}

	static void sun4d_load_profile_irq(int cpu, unsigned int limit)
	{
	bw_set_prof_limit(cpu, limit);
	}

	static void __init sun4d_init_timers(irq_handler_t counter_fn)
	{
	int irq;
	int cpu;
	struct resource r;
	int mid;

	/* Map the User Timer registers. */
	memset(&r, 0, sizeof(r));
	#ifdef CONFIG_SMP
	r.start = CSR_BASE(boot_cpu_id)+BW_TIMER_LIMIT;
	#else
	r.start = CSR_BASE(0)+BW_TIMER_LIMIT;
	#endif
	r.flags = 0xf;
	sun4d_timers = (struct sun4d_timer_regs *) sbus_ioremap(&r, 0,
	PAGE_SIZE, "user timer");

	sun4d_timers->l10_timer_limit = (((1000000/HZ) + 1) << 10);
	master_l10_counter = &sun4d_timers->l10_cur_count;
	master_l10_limit = &sun4d_timers->l10_timer_limit;

	irq = request_irq(TIMER_IRQ,
	counter_fn,
	(IRQF_DISABLED \| SA_STATIC_ALLOC),
	"timer", NULL);
	if (irq) {
	prom_printf("time_init: unable to attach IRQ%d\n",TIMER_IRQ);
	prom_halt();
	}

	/* Enable user timer free run for CPU 0 in BW */
	/* bw_set_ctrl(0, bw_get_ctrl(0) \| BW_CTRL_USER_TIMER); */

	cpu = 0;
	while (!cpu_find_by_instance(cpu, NULL, &mid)) {
	sun4d_load_profile_irq(mid >> 3, 0);
	cpu++;
	}

	#ifdef CONFIG_SMP
	{
	unsigned long flags;
	extern unsigned long lvl14_save[4];
	struct tt_entry *trap_table = &sparc_ttable[SP_TRAP_IRQ1 + (14 - 1)];
	extern unsigned int real_irq_entry[], smp4d_ticker[];
	extern unsigned int patchme_maybe_smp_msg[];

	/* Adjust so that we jump directly to smp4d_ticker */
	lvl14_save[2] += smp4d_ticker - real_irq_entry;

	/* For SMP we use the level 14 ticker, however the bootup code
	* has copied the firmware's level 14 vector into the boot cpu's
	* trap table, we must fix this now or we get squashed.
	*/
	local_irq_save(flags);
	patchme_maybe_smp_msg[0] = 0x01000000; /* NOP out the branch */
	trap_table->inst_one = lvl14_save[0];
	trap_table->inst_two = lvl14_save[1];
	trap_table->inst_three = lvl14_save[2];
	trap_table->inst_four = lvl14_save[3];
	local_flush_cache_all();
	local_irq_restore(flags);
	}
	#endif
	}

	void __init sun4d_init_sbi_irq(void)
	{
	struct device_node *dp;

	nsbi = 0;
	for_each_node_by_name(dp, "sbi")
	nsbi++;
	sbus_actions = kzalloc (nsbi * 8 * 4 * sizeof(struct sbus_action), GFP_ATOMIC);
	if (!sbus_actions) {
	prom_printf("SUN4D: Cannot allocate sbus_actions, halting.\n");
	prom_halt();
	}
	for_each_node_by_name(dp, "sbi") {
	int devid = of_getintprop_default(dp, "device-id", 0);
	int board = of_getintprop_default(dp, "board#", 0);
	unsigned int mask;

	#ifdef CONFIG_SMP
	{
	extern unsigned char boot_cpu_id;

	set_sbi_tid(devid, boot_cpu_id << 3);
	sbus_tid[board] = boot_cpu_id;
	}
	#endif
	/* Get rid of pending irqs from PROM */
	mask = acquire_sbi(devid, 0xffffffff);
	if (mask) {
	printk ("Clearing pending IRQs %08x on SBI %d\n", mask, board);
	release_sbi(devid, mask);
	}
	}
	}

	void __init sun4d_init_IRQ(void)
	{
	local_irq_disable();

	BTFIXUPSET_CALL(enable_irq, sun4d_enable_irq, BTFIXUPCALL_NORM);
	BTFIXUPSET_CALL(disable_irq, sun4d_disable_irq, BTFIXUPCALL_NORM);
	BTFIXUPSET_CALL(clear_clock_irq, sun4d_clear_clock_irq, BTFIXUPCALL_NORM);
	BTFIXUPSET_CALL(clear_profile_irq, sun4d_clear_profile_irq, BTFIXUPCALL_NORM);
	BTFIXUPSET_CALL(load_profile_irq, sun4d_load_profile_irq, BTFIXUPCALL_NORM);
	sparc_init_timers = sun4d_init_timers;
	#ifdef CONFIG_SMP
	BTFIXUPSET_CALL(set_cpu_int, sun4d_set_cpu_int, BTFIXUPCALL_NORM);
	BTFIXUPSET_CALL(clear_cpu_int, sun4d_clear_ipi, BTFIXUPCALL_NOP);
	BTFIXUPSET_CALL(set_irq_udt, sun4d_set_udt, BTFIXUPCALL_NOP);
	#endif
	/* Cannot enable interrupts until OBP ticker is disabled. */
	}