patch-2.4.19 linux-2.4.19/arch/ppc64/kernel/irq.c

Next file: linux-2.4.19/arch/ppc64/kernel/lmb.c
Previous file: linux-2.4.19/arch/ppc64/kernel/ioctl32.c
Back to the patch index
Back to the overall index

diff -urN linux-2.4.18/arch/ppc64/kernel/irq.c linux-2.4.19/arch/ppc64/kernel/irq.c
@@ -0,0 +1,973 @@
+/*
+ * 
+ *
+ *  arch/ppc/kernel/irq.c
+ *
+ *  Derived from arch/i386/kernel/irq.c
+ *    Copyright (C) 1992 Linus Torvalds
+ *  Adapted from arch/i386 by Gary Thomas
+ *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *  Updated and modified by Cort Dougan (cort@cs.nmt.edu)
+ *    Copyright (C) 1996 Cort Dougan
+ *  Adapted for Power Macintosh by Paul Mackerras
+ *    Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au)
+ *  Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
+ * 
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * This file contains the code used by various IRQ handling routines:
+ * asking for different IRQ's should be done through these routines
+ * instead of just grabbing them. Thus setups with different IRQ numbers
+ * shouldn't result in any weird surprises, and installing new handlers
+ * should be easier.
+ */
+
+
+#include <linux/ptrace.h>
+#include <linux/errno.h>
+#include <linux/threads.h>
+#include <linux/kernel_stat.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/ioport.h>
+#include <linux/interrupt.h>
+#include <linux/timex.h>
+#include <linux/config.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/pci.h>
+#include <linux/delay.h>
+#include <linux/irq.h>
+#include <linux/proc_fs.h>
+#include <linux/random.h>
+
+#include <asm/uaccess.h>
+#include <asm/bitops.h>
+#include <asm/system.h>
+#include <asm/io.h>
+#include <asm/pgtable.h>
+#include <asm/irq.h>
+#include <asm/cache.h>
+#include <asm/prom.h>
+#include <asm/ptrace.h>
+#include <asm/iSeries/LparData.h>
+#include <asm/machdep.h>
+#include <asm/paca.h>
+
+#include "local_irq.h"
+
+atomic_t ipi_recv;
+atomic_t ipi_sent;
+void enable_irq(unsigned int irq_nr);
+void disable_irq(unsigned int irq_nr);
+
+#ifdef CONFIG_SMP
+extern void iSeries_smp_message_recv( struct pt_regs * );
+#endif
+
+volatile unsigned char *chrp_int_ack_special;
+static void register_irq_proc (unsigned int irq);
+
+irq_desc_t irq_desc[NR_IRQS] __cacheline_aligned =
+	{ [0 ... NR_IRQS-1] = { 0, NULL, NULL, 0, SPIN_LOCK_UNLOCKED}};
+	
+int ppc_spurious_interrupts = 0;
+struct irqaction *ppc_irq_action[NR_IRQS];
+unsigned long lpEvent_count = 0;
+#ifdef CONFIG_XMON
+extern void xmon(struct pt_regs *regs);
+extern int xmon_bpt(struct pt_regs *regs);
+extern int xmon_sstep(struct pt_regs *regs);
+extern int xmon_iabr_match(struct pt_regs *regs);
+extern int xmon_dabr_match(struct pt_regs *regs);
+extern void (*xmon_fault_handler)(struct pt_regs *regs);
+#endif
+#ifdef CONFIG_XMON
+extern void (*debugger)(struct pt_regs *regs);
+extern int (*debugger_bpt)(struct pt_regs *regs);
+extern int (*debugger_sstep)(struct pt_regs *regs);
+extern int (*debugger_iabr_match)(struct pt_regs *regs);
+extern int (*debugger_dabr_match)(struct pt_regs *regs);
+extern void (*debugger_fault_handler)(struct pt_regs *regs);
+#endif
+
+/* nasty hack for shared irq's since we need to do kmalloc calls but
+ * can't very early in the boot when we need to do a request irq.
+ * this needs to be removed.
+ * -- Cort
+ */
+#define IRQ_KMALLOC_ENTRIES 8
+static int cache_bitmask = 0;
+static struct irqaction malloc_cache[IRQ_KMALLOC_ENTRIES];
+extern int mem_init_done;
+
+void *irq_kmalloc(size_t size, int pri)
+{
+	unsigned int i;
+	if ( mem_init_done )
+		return kmalloc(size,pri);
+	for ( i = 0; i < IRQ_KMALLOC_ENTRIES ; i++ )
+		if ( ! ( cache_bitmask & (1<<i) ) ) {
+			cache_bitmask |= (1<<i);
+			return (void *)(&malloc_cache[i]);
+		}
+	return 0;
+}
+
+void irq_kfree(void *ptr)
+{
+	unsigned int i;
+	for ( i = 0 ; i < IRQ_KMALLOC_ENTRIES ; i++ )
+		if ( ptr == &malloc_cache[i] ) {
+			cache_bitmask &= ~(1<<i);
+			return;
+		}
+	kfree(ptr);
+}
+
+int
+setup_irq(unsigned int irq, struct irqaction * new)
+{
+	int shared = 0;
+	unsigned long flags;
+	struct irqaction *old, **p;
+	irq_desc_t *desc = irq_desc + irq;
+
+	/*
+	 * Some drivers like serial.c use request_irq() heavily,
+	 * so we have to be careful not to interfere with a
+	 * running system.
+	 */
+	if (new->flags & SA_SAMPLE_RANDOM) {
+		/*
+		 * This function might sleep, we want to call it first,
+		 * outside of the atomic block.
+		 * Yes, this might clear the entropy pool if the wrong
+		 * driver is attempted to be loaded, without actually
+		 * installing a new handler, but is this really a problem,
+		 * only the sysadmin is able to do this.
+		 */
+		rand_initialize_irq(irq);
+	}
+
+	/*
+	 * The following block of code has to be executed atomically
+	 */
+	spin_lock_irqsave(&desc->lock,flags);
+	p = &desc->action;
+	if ((old = *p) != NULL) {
+		/* Can't share interrupts unless both agree to */
+		if (!(old->flags & new->flags & SA_SHIRQ)) {
+			spin_unlock_irqrestore(&desc->lock,flags);
+			return -EBUSY;
+		}
+
+		/* add new interrupt at end of irq queue */
+		do {
+			p = &old->next;
+			old = *p;
+		} while (old);
+		shared = 1;
+	}
+
+	*p = new;
+
+	if (!shared) {
+		desc->depth = 0;
+		desc->status &= ~(IRQ_DISABLED | IRQ_AUTODETECT | IRQ_WAITING);
+		unmask_irq(irq);
+	}
+	spin_unlock_irqrestore(&desc->lock,flags);
+
+	register_irq_proc(irq);
+	return 0;
+}
+
+/* This could be promoted to a real free_irq() ... */
+static int
+do_free_irq(int irq, void* dev_id)
+{
+	irq_desc_t *desc;
+	struct irqaction **p;
+	unsigned long flags;
+
+	desc = irq_desc + irq;
+	spin_lock_irqsave(&desc->lock,flags);
+	p = &desc->action;
+	for (;;) {
+		struct irqaction * action = *p;
+		if (action) {
+			struct irqaction **pp = p;
+			p = &action->next;
+			if (action->dev_id != dev_id)
+				continue;
+
+			/* Found it - now remove it from the list of entries */
+			*pp = action->next;
+			if (!desc->action) {
+				desc->status |= IRQ_DISABLED;
+				mask_irq(irq);
+			}
+			spin_unlock_irqrestore(&desc->lock,flags);
+
+#ifdef CONFIG_SMP
+			/* Wait to make sure it's not being used on another CPU */
+			while (desc->status & IRQ_INPROGRESS)
+				barrier();
+#endif
+			irq_kfree(action);
+			return 0;
+		}
+		printk("Trying to free free IRQ%d\n",irq);
+		spin_unlock_irqrestore(&desc->lock,flags);
+		break;
+	}
+	return -ENOENT;
+}
+
+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;
+	int retval;
+
+	if (irq >= NR_IRQS)
+		return -EINVAL;
+	if (!handler)
+		/* We could implement really free_irq() instead of that... */
+		return do_free_irq(irq, dev_id);
+	
+	action = (struct irqaction *)
+		irq_kmalloc(sizeof(struct irqaction), GFP_KERNEL);
+	if (!action) {
+		printk(KERN_ERR "irq_kmalloc() failed for irq %d !\n", irq);
+		return -ENOMEM;
+	}
+	
+	action->handler = handler;
+	action->flags = irqflags;					
+	action->mask = 0;
+	action->name = devname;
+	action->dev_id = dev_id;
+	action->next = NULL;
+	
+	retval = setup_irq(irq, action);
+	if (retval)
+		kfree(action);
+		
+	return 0;
+}
+
+void free_irq(unsigned int irq, void *dev_id)
+{
+	request_irq(irq, NULL, 0, NULL, dev_id);
+}
+
+/*
+ * Generic enable/disable code: this just calls
+ * down into the PIC-specific version for the actual
+ * hardware disable after having gotten the irq
+ * controller lock. 
+ */
+ 
+/**
+ *	disable_irq_nosync - disable an irq without waiting
+ *	@irq: Interrupt to disable
+ *
+ *	Disable the selected interrupt line. Disables of an interrupt
+ *	stack. Unlike disable_irq(), this function does not ensure existing
+ *	instances of the IRQ handler have completed before returning.
+ *
+ *	This function may be called from IRQ context.
+ */
+ 
+ void disable_irq_nosync(unsigned int irq)
+{
+	irq_desc_t *desc = irq_desc + irq;
+	unsigned long flags;
+
+	spin_lock_irqsave(&desc->lock, flags);
+	if (!desc->depth++) {
+		if (!(desc->status & IRQ_PER_CPU))
+			desc->status |= IRQ_DISABLED;
+		mask_irq(irq);
+	}
+	spin_unlock_irqrestore(&desc->lock, flags);
+}
+
+/**
+ *	disable_irq - disable an irq and wait for completion
+ *	@irq: Interrupt to disable
+ *
+ *	Disable the selected interrupt line. Disables of an interrupt
+ *	stack. That is for two disables you need two enables. This
+ *	function waits for any pending IRQ handlers for this interrupt
+ *	to complete before returning. If you use this function while
+ *	holding a resource the IRQ handler may need you will deadlock.
+ *
+ *	This function may be called - with care - from IRQ context.
+ */
+ 
+void disable_irq(unsigned int irq)
+{
+	disable_irq_nosync(irq);
+
+	if (!local_irq_count(smp_processor_id())) {
+		do {
+			barrier();
+		} while (irq_desc[irq].status & IRQ_INPROGRESS);
+	}
+}
+
+/**
+ *	enable_irq - enable interrupt handling on an irq
+ *	@irq: Interrupt to enable
+ *
+ *	Re-enables the processing of interrupts on this IRQ line
+ *	providing no disable_irq calls are now in effect.
+ *
+ *	This function may be called from IRQ context.
+ */
+ 
+void enable_irq(unsigned int irq)
+{
+	irq_desc_t *desc = irq_desc + irq;
+	unsigned long flags;
+
+	spin_lock_irqsave(&desc->lock, flags);
+	switch (desc->depth) {
+	case 1: {
+		unsigned int status = desc->status & ~IRQ_DISABLED;
+		desc->status = status;
+		if ((status & (IRQ_PENDING | IRQ_REPLAY)) == IRQ_PENDING) {
+			desc->status = status | IRQ_REPLAY;
+			hw_resend_irq(desc->handler,irq);
+		}
+		unmask_irq(irq);
+		/* fall-through */
+	}
+	default:
+		desc->depth--;
+		break;
+	case 0:
+		printk("enable_irq(%u) unbalanced\n", irq);
+	}
+	spin_unlock_irqrestore(&desc->lock, flags);
+}
+
+/* one would think this function has one foot in the grave */
+int get_irq_list(char *buf)
+{
+   int i, len = 0, j;
+   struct irqaction * action;
+
+   len += sprintf(buf+len, "           ");
+   for (j=0; j<smp_num_cpus; j++)
+       len += sprintf(buf+len, "CPU%d       ",j);
+   *(char *)(buf+len++) = '\n';
+
+   for (i = 0 ; i < NR_IRQS ; i++) {
+       action = irq_desc[i].action;
+       if ( !action || !action->handler )
+           continue;
+       len += sprintf(buf+len, "%3d: ", i);
+#ifdef CONFIG_SMP
+       for (j = 0; j < smp_num_cpus; j++)
+           len += sprintf(buf+len, "%10u ",
+               kstat.irqs[cpu_logical_map(j)][i]);
+#else
+       len += sprintf(buf+len, "%10u ", kstat_irqs(i));
+#endif /* CONFIG_SMP */
+if ( irq_desc[i].handler )
+len += sprintf(buf+len, " %s ", irq_desc[i].handler->typename );
+else
+len += sprintf(buf+len, "  None      ");
+len += sprintf(buf+len, "%s", (irq_desc[i].status & IRQ_LEVEL) ? "Level " : "Edge  ");
+len += sprintf(buf+len, "    %s",action->name);
+for (action=action->next; action; action = action->next) {
+len += sprintf(buf+len, ", %s", action->name);
+}
+len += sprintf(buf+len, "\n");
+}
+#ifdef CONFIG_SMP
+/* should this be per processor send/receive? */
+len += sprintf(buf+len, "IPI (recv/sent): %10u/%u\n",
+atomic_read(&ipi_recv), atomic_read(&ipi_sent));
+#endif
+len += sprintf(buf+len, "BAD: %10u\n", ppc_spurious_interrupts);
+return len;
+}
+
+
+
+int show_interrupts(struct seq_file *p, void *v)
+{
+	int i, j;
+	struct irqaction * action;
+
+	seq_printf(p, "           ");
+	for (j=0; j<smp_num_cpus; j++)
+		seq_printf(p, "CPU%d       ",j);
+	seq_putc(p, '\n');
+
+	for (i = 0 ; i < NR_IRQS ; i++) {
+		action = irq_desc[i].action;
+		if (!action || !action->handler)
+			continue;
+		seq_printf(p, "%3d: ", i);		
+#ifdef CONFIG_SMP
+		for (j = 0; j < smp_num_cpus; j++)
+			seq_printf(p, "%10u ",
+				kstat.irqs[cpu_logical_map(j)][i]);
+#else		
+		seq_printf(p, "%10u ", kstat_irqs(i));
+#endif /* CONFIG_SMP */
+		if (irq_desc[i].handler)		
+			seq_printf(p, " %s ", irq_desc[i].handler->typename );
+		else
+			seq_printf(p, "  None      ");
+		seq_printf(p, "%s", (irq_desc[i].status & IRQ_LEVEL) ? "Level " : "Edge  ");
+		seq_printf(p, "    %s",action->name);
+		for (action=action->next; action; action = action->next)
+			seq_printf(p, ", %s", action->name);
+		seq_putc(p, '\n');
+	}
+#ifdef CONFIG_SMP
+	/* should this be per processor send/receive? */
+	seq_printf(p, "IPI (recv/sent): %10u/%u\n",
+		       atomic_read(&ipi_recv), atomic_read(&ipi_sent));
+#endif		
+	seq_printf(p, "BAD: %10u\n", ppc_spurious_interrupts);
+	return 0;
+}
+
+static inline void
+handle_irq_event(int irq, struct pt_regs *regs, struct irqaction *action)
+{
+	int status = 0;
+
+	if (!(action->flags & SA_INTERRUPT))
+		__sti();
+
+	do {
+		status |= action->flags;
+		action->handler(irq, action->dev_id, regs);
+		action = action->next;
+	} while (action);
+	if (status & SA_SAMPLE_RANDOM)
+		add_interrupt_randomness(irq);
+	__cli();
+}
+
+/*
+ * Eventually, this should take an array of interrupts and an array size
+ * so it can dispatch multiple interrupts.
+ */
+void ppc_irq_dispatch_handler(struct pt_regs *regs, int irq)
+{
+	int status;
+	struct irqaction *action;
+	int cpu = smp_processor_id();
+	irq_desc_t *desc = irq_desc + irq;
+
+	kstat.irqs[cpu][irq]++;
+	spin_lock(&desc->lock);
+	ack_irq(irq);	
+	/*
+	   REPLAY is when Linux resends an IRQ that was dropped earlier
+	   WAITING is used by probe to mark irqs that are being tested
+	   */
+	status = desc->status & ~(IRQ_REPLAY | IRQ_WAITING);
+	if (!(status & IRQ_PER_CPU))
+		status |= IRQ_PENDING; /* we _want_ to handle it */
+
+	/*
+	 * If the IRQ is disabled for whatever reason, we cannot
+	 * use the action we have.
+	 */
+	action = NULL;
+	if (!(status & (IRQ_DISABLED | IRQ_INPROGRESS))) {
+		action = desc->action;
+		if (!action || !action->handler) {
+			ppc_spurious_interrupts++;
+			printk(KERN_DEBUG "Unhandled interrupt %x, disabled\n", irq);
+			/* We can't call disable_irq here, it would deadlock */
+			if (!desc->depth)
+				desc->depth = 1;
+			desc->status |= IRQ_DISABLED;
+			/* This is not a real spurrious interrupt, we
+			 * have to eoi it, so we jump to out
+			 */
+			mask_irq(irq);
+			goto out;
+		}
+		status &= ~IRQ_PENDING; /* we commit to handling */
+		if (!(status & IRQ_PER_CPU))
+			status |= IRQ_INPROGRESS; /* we are handling it */
+	}
+	desc->status = status;
+
+	/*
+	 * If there is no IRQ handler or it was disabled, exit early.
+	   Since we set PENDING, if another processor is handling
+	   a different instance of this same irq, the other processor
+	   will take care of it.
+	 */
+	if (!action)
+		goto out;
+
+
+	/*
+	 * Edge triggered interrupts need to remember
+	 * pending events.
+	 * This applies to any hw interrupts that allow a second
+	 * instance of the same irq to arrive while we are in do_IRQ
+	 * or in the handler. But the code here only handles the _second_
+	 * instance of the irq, not the third or fourth. So it is mostly
+	 * useful for irq hardware that does not mask cleanly in an
+	 * SMP environment.
+	 */
+	for (;;) {
+		spin_unlock(&desc->lock);
+		handle_irq_event(irq, regs, action);
+		spin_lock(&desc->lock);
+		
+		if (!(desc->status & IRQ_PENDING))
+			break;
+		desc->status &= ~IRQ_PENDING;
+	}
+	desc->status &= ~IRQ_INPROGRESS;
+out:
+	/*
+	 * The ->end() handler has to deal with interrupts which got
+	 * disabled while the handler was running.
+	 */
+	if (irq_desc[irq].handler) {
+		if (irq_desc[irq].handler->end)
+			irq_desc[irq].handler->end(irq);
+		else if (irq_desc[irq].handler->enable)
+			irq_desc[irq].handler->enable(irq);
+	}
+	spin_unlock(&desc->lock);
+}
+
+int do_IRQ(struct pt_regs *regs, int isfake)
+{
+	int cpu = smp_processor_id();
+	int irq;
+	struct paca_struct *lpaca;
+	struct ItLpQueue * lpq;
+
+	/* if(cpu) udbg_printf("Entering do_IRQ\n");  */
+
+        irq_enter(cpu);
+
+	if (naca->platform != PLATFORM_ISERIES_LPAR) {
+	
+		/* every arch is required to have a get_irq -- Cort */
+		irq = ppc_md.get_irq( regs );
+
+		if ( irq >= 0 ) {
+			ppc_irq_dispatch_handler( regs, irq );
+			if (ppc_md.post_irq)
+				ppc_md.post_irq( regs, irq );
+		} else {
+			/* -2 means ignore, already handled */
+			if (irq != -2) {
+				printk(KERN_DEBUG "Bogus interrupt %d from PC = %lx\n",
+					irq, regs->nip);
+				ppc_spurious_interrupts++;
+			}
+		}
+	}
+	/* if on iSeries partition */
+	else {
+		lpaca = get_paca();
+#ifdef CONFIG_SMP
+		if ( lpaca->xLpPaca.xIntDword.xFields.xIpiCnt ) {
+			lpaca->xLpPaca.xIntDword.xFields.xIpiCnt = 0;
+			iSeries_smp_message_recv( regs );
+		}
+#endif /* CONFIG_SMP */
+		lpq = lpaca->lpQueuePtr;
+		if ( lpq && ItLpQueue_isLpIntPending( lpq ) )
+			lpEvent_count += ItLpQueue_process( lpq, regs );
+	}
+		
+        irq_exit(cpu);
+
+	if (naca->platform == PLATFORM_ISERIES_LPAR) {
+		if ( lpaca->xLpPaca.xIntDword.xFields.xDecrInt ) {
+			lpaca->xLpPaca.xIntDword.xFields.xDecrInt = 0;
+			/* Signal a fake decrementer interrupt */
+			timer_interrupt( regs );
+		}
+	}
+
+	if (softirq_pending(cpu))
+		do_softirq();
+
+	return 1; /* lets ret_from_int know we can do checks */
+}
+
+unsigned long probe_irq_on (void)
+{
+	return 0;
+}
+
+int probe_irq_off (unsigned long irqs)
+{
+	return 0;
+}
+
+unsigned int probe_irq_mask(unsigned long irqs)
+{
+	return 0;
+}
+
+void __init init_IRQ(void)
+{
+	static int once = 0;
+
+	if ( once )
+		return;
+	else
+		once++;
+	
+	ppc_md.init_IRQ();
+	if(ppc_md.init_ras_IRQ) ppc_md.init_ras_IRQ(); 
+}
+
+#ifdef CONFIG_SMP
+unsigned char global_irq_holder = NO_PROC_ID;
+
+static void show(char * str)
+{
+	int cpu = smp_processor_id();
+	int i;
+
+	printk("\n%s, CPU %d:\n", str, cpu);
+	printk("irq:  %d [ ", irqs_running());
+	for (i = 0; i < smp_num_cpus; i++)
+		printk("%u ", __brlock_array[i][BR_GLOBALIRQ_LOCK]);
+	printk("]\nbh:   %d [ ",
+		(spin_is_locked(&global_bh_lock) ? 1 : 0));
+	for (i = 0; i < smp_num_cpus; i++)
+		printk("%u ", local_bh_count(i));
+	printk("]\n");
+}
+
+#define MAXCOUNT 10000000
+
+void synchronize_irq(void)
+{
+	if (irqs_running()) {
+		cli();
+		sti();
+	}
+}
+
+static inline void get_irqlock(int cpu)
+{
+        int count;
+
+        if ((unsigned char)cpu == global_irq_holder)
+                return;
+
+        count = MAXCOUNT;
+again:
+        br_write_lock(BR_GLOBALIRQ_LOCK);
+        for (;;) {
+                spinlock_t *lock;
+
+                if (!irqs_running() &&
+                    (local_bh_count(smp_processor_id()) || !spin_is_locked(&global_bh_lock)))
+                        break;
+
+                br_write_unlock(BR_GLOBALIRQ_LOCK);
+                lock = &__br_write_locks[BR_GLOBALIRQ_LOCK].lock;
+                while (irqs_running() ||
+                       spin_is_locked(lock) ||
+                       (!local_bh_count(smp_processor_id()) && spin_is_locked(&global_bh_lock))) {
+                        if (!--count) {
+                                show("get_irqlock");
+                                count = (~0 >> 1);
+                        }
+                        __sti();
+                        barrier();
+                        __cli();
+                }
+                goto again;
+        }
+
+        global_irq_holder = cpu;
+}
+
+/*
+ * A global "cli()" while in an interrupt context
+ * turns into just a local cli(). Interrupts
+ * should use spinlocks for the (very unlikely)
+ * case that they ever want to protect against
+ * each other.
+ *
+ * If we already have local interrupts disabled,
+ * this will not turn a local disable into a
+ * global one (problems with spinlocks: this makes
+ * save_flags+cli+sti usable inside a spinlock).
+ */
+void __global_cli(void)
+{
+	unsigned long flags;
+	
+	__save_flags(flags);
+	if (flags & (1UL << 15)) {
+		int cpu = smp_processor_id();
+		__cli();
+		if (!local_irq_count(cpu))
+			get_irqlock(cpu);
+	}
+}
+
+void __global_sti(void)
+{
+	int cpu = smp_processor_id();
+
+	if (!local_irq_count(cpu))
+		release_irqlock(cpu);
+	__sti();
+}
+
+/*
+ * SMP flags value to restore to:
+ * 0 - global cli
+ * 1 - global sti
+ * 2 - local cli
+ * 3 - local sti
+ */
+unsigned long __global_save_flags(void)
+{
+	int retval;
+	int local_enabled;
+	unsigned long flags;
+
+	__save_flags(flags);
+	local_enabled = (flags >> 15) & 1;
+	/* default to local */
+	retval = 2 + local_enabled;
+
+	/* check for global flags if we're not in an interrupt */
+	if (!local_irq_count(smp_processor_id())) {
+		if (local_enabled)
+			retval = 1;
+		if (global_irq_holder == (unsigned char) smp_processor_id())
+			retval = 0;
+	}
+	return retval;
+}
+
+void __global_restore_flags(unsigned long flags)
+{
+	switch (flags) {
+	case 0:
+		__global_cli();
+		break;
+	case 1:
+		__global_sti();
+		break;
+	case 2:
+		__cli();
+		break;
+	case 3:
+		__sti();
+		break;
+	default:
+		printk("global_restore_flags: %016lx caller %p\n",
+			flags, __builtin_return_address(0));
+	}
+}
+
+#endif /* CONFIG_SMP */
+
+static struct proc_dir_entry * root_irq_dir;
+static struct proc_dir_entry * irq_dir [NR_IRQS];
+static struct proc_dir_entry * smp_affinity_entry [NR_IRQS];
+
+#ifdef CONFIG_IRQ_ALL_CPUS
+unsigned int irq_affinity [NR_IRQS] = { [0 ... NR_IRQS-1] = 0xffffffff};
+#else  /* CONFIG_IRQ_ALL_CPUS */
+unsigned int irq_affinity [NR_IRQS] = { [0 ... NR_IRQS-1] = 0x00000000};
+#endif /* CONFIG_IRQ_ALL_CPUS */
+
+#define HEX_DIGITS 8
+
+static int irq_affinity_read_proc (char *page, char **start, off_t off,
+			int count, int *eof, void *data)
+{
+	if (count < HEX_DIGITS+1)
+		return -EINVAL;
+	return sprintf (page, "%08x\n", irq_affinity[(int)(long)data]);
+}
+
+static unsigned int parse_hex_value (const char *buffer,
+		unsigned long count, unsigned long *ret)
+{
+	unsigned char hexnum [HEX_DIGITS];
+	unsigned long value;
+	int i;
+
+	if (!count)
+		return -EINVAL;
+	if (count > HEX_DIGITS)
+		count = HEX_DIGITS;
+	if (copy_from_user(hexnum, buffer, count))
+		return -EFAULT;
+
+	/*
+	 * Parse the first 8 characters as a hex string, any non-hex char
+	 * is end-of-string. '00e1', 'e1', '00E1', 'E1' are all the same.
+	 */
+	value = 0;
+
+	for (i = 0; i < count; i++) {
+		unsigned int c = hexnum[i];
+
+		switch (c) {
+			case '0' ... '9': c -= '0'; break;
+			case 'a' ... 'f': c -= 'a'-10; break;
+			case 'A' ... 'F': c -= 'A'-10; break;
+		default:
+			goto out;
+		}
+		value = (value << 4) | c;
+	}
+out:
+	*ret = value;
+	return 0;
+}
+
+static int irq_affinity_write_proc (struct file *file, const char *buffer,
+					unsigned long count, void *data)
+{
+	int irq = (int)(long) data, full_count = count, err;
+	unsigned long new_value;
+
+	if (!irq_desc[irq].handler->set_affinity)
+		return -EIO;
+
+	err = parse_hex_value(buffer, count, &new_value);
+
+/* Why is this disabled ? --BenH */
+#if 0/*CONFIG_SMP*/
+	/*
+	 * Do not allow disabling IRQs completely - it's a too easy
+	 * way to make the system unusable accidentally :-) At least
+	 * one online CPU still has to be targeted.
+	 */
+	if (!(new_value & cpu_online_map))
+		return -EINVAL;
+#endif
+
+	irq_affinity[irq] = new_value;
+	irq_desc[irq].handler->set_affinity(irq, new_value);
+
+	return full_count;
+}
+
+static int prof_cpu_mask_read_proc (char *page, char **start, off_t off,
+			int count, int *eof, void *data)
+{
+	unsigned long *mask = (unsigned long *) data;
+	if (count < HEX_DIGITS+1)
+		return -EINVAL;
+	return sprintf (page, "%08lx\n", *mask);
+}
+
+static int prof_cpu_mask_write_proc (struct file *file, const char *buffer,
+					unsigned long count, void *data)
+{
+	unsigned long *mask = (unsigned long *) data, full_count = count, err;
+	unsigned long new_value;
+
+	err = parse_hex_value(buffer, count, &new_value);
+	if (err)
+		return err;
+
+	*mask = new_value;
+
+#ifdef CONFIG_PPC_ISERIES
+	{
+		unsigned i;
+		for (i=0; i<MAX_PACAS; ++i) {
+			if ( paca[i].prof_buffer && (new_value & 1) )
+				paca[i].prof_enabled = 1;
+			else
+				paca[i].prof_enabled = 0;
+			new_value >>= 1;
+		}
+	}
+#endif
+
+	return full_count;
+}
+
+#define MAX_NAMELEN 10
+
+static void register_irq_proc (unsigned int irq)
+{
+	struct proc_dir_entry *entry;
+	char name [MAX_NAMELEN];
+
+	if (!root_irq_dir || (irq_desc[irq].handler == NULL))
+		return;
+
+	memset(name, 0, MAX_NAMELEN);
+	sprintf(name, "%d", irq);
+
+	/* create /proc/irq/1234 */
+	irq_dir[irq] = proc_mkdir(name, root_irq_dir);
+
+	/* create /proc/irq/1234/smp_affinity */
+	entry = create_proc_entry("smp_affinity", 0600, irq_dir[irq]);
+
+	entry->nlink = 1;
+	entry->data = (void *)(long)irq;
+	entry->read_proc = irq_affinity_read_proc;
+	entry->write_proc = irq_affinity_write_proc;
+
+	smp_affinity_entry[irq] = entry;
+}
+
+unsigned long prof_cpu_mask = -1;
+
+void init_irq_proc (void)
+{
+	struct proc_dir_entry *entry;
+	int i;
+
+	/* create /proc/irq */
+	root_irq_dir = proc_mkdir("irq", 0);
+
+	/* create /proc/irq/prof_cpu_mask */
+	entry = create_proc_entry("prof_cpu_mask", 0600, root_irq_dir);
+
+	entry->nlink = 1;
+	entry->data = (void *)&prof_cpu_mask;
+	entry->read_proc = prof_cpu_mask_read_proc;
+	entry->write_proc = prof_cpu_mask_write_proc;
+
+	/*
+	 * Create entries for all existing IRQs.
+	 */
+	for (i = 0; i < NR_IRQS; i++) {
+		if (irq_desc[i].handler == NULL)
+			continue;
+		register_irq_proc(i);
+	}
+}
+
+void no_action(int irq, void *dev, struct pt_regs *regs)
+{
+}
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)