irq.c

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	bucket->flags |= IBF_INPROGRESS;

	floppy_interrupt(irq, dev_cookie, regs);
	upa_writel(ICLR_IDLE, bucket->iclr);

	bucket->flags &= ~IBF_INPROGRESS;

	irq_exit();
}
#endif

/* The following assumes that the branch lies before the place we
 * are branching to.  This is the case for a trap vector...
 * You have been warned.
 */
#define SPARC_BRANCH(dest_addr, inst_addr) \
          (0x10800000 | ((((dest_addr)-(inst_addr))>>2)&0x3fffff))

#define SPARC_NOP (0x01000000)

static void install_fast_irq(unsigned int cpu_irq,
			     irqreturn_t (*handler)(int, void *, struct pt_regs *))
{
	extern unsigned long sparc64_ttable_tl0;
	unsigned long ttent = (unsigned long) &sparc64_ttable_tl0;
	unsigned int *insns;

	ttent += 0x820;
	ttent += (cpu_irq - 1) << 5;
	insns = (unsigned int *) ttent;
	insns[0] = SPARC_BRANCH(((unsigned long) handler),
				((unsigned long)&insns[0]));
	insns[1] = SPARC_NOP;
	__asm__ __volatile__("membar #StoreStore; flush %0" : : "r" (ttent));
}

int request_fast_irq(unsigned int irq,
		     irqreturn_t (*handler)(int, void *, struct pt_regs *),
		     unsigned long irqflags, const char *name, void *dev_id)
{
	struct irqaction *action;
	struct ino_bucket *bucket = __bucket(irq);
	unsigned long flags;

	/* No pil0 dummy buckets allowed here. */
	if (bucket < &ivector_table[0] ||
	    bucket >= &ivector_table[NUM_IVECS]) {
		unsigned int *caller;

		__asm__ __volatile__("mov %%i7, %0" : "=r" (caller));
		printk(KERN_CRIT "request_fast_irq: Old style IRQ registry attempt "
		       "from %p, irq %08x.\n", caller, irq);
		return -EINVAL;
	}	
	
	if (!handler)
		return -EINVAL;

	if ((bucket->pil == 0) || (bucket->pil == 14)) {
		printk("request_fast_irq: Trying to register shared IRQ 0 or 14.\n");
		return -EBUSY;
	}

	spin_lock_irqsave(&irq_action_lock, flags);

	action = *(bucket->pil + irq_action);
	if (action) {
		if (action->flags & SA_SHIRQ)
			panic("Trying to register fast irq when already shared.\n");
		if (irqflags & SA_SHIRQ)
			panic("Trying to register fast irq as shared.\n");
		printk("request_fast_irq: Trying to register yet already owned.\n");
		spin_unlock_irqrestore(&irq_action_lock, flags);
		return -EBUSY;
	}

	/*
	 * We do not check for SA_SAMPLE_RANDOM in this path. Neither do we
	 * support smp intr affinity in this path.
	 */
	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", bucket->pil, name);
	}
	if (action == NULL)
		action = (struct irqaction *)kmalloc(sizeof(struct irqaction),
						     GFP_ATOMIC);
	if (!action) {
		spin_unlock_irqrestore(&irq_action_lock, flags);
		return -ENOMEM;
	}
	install_fast_irq(bucket->pil, handler);

	bucket->irq_info = action;
	bucket->flags |= IBF_ACTIVE;

	action->handler = handler;
	action->flags = irqflags;
	action->dev_id = NULL;
	action->name = name;
	action->next = NULL;
	put_ino_in_irqaction(action, irq);
	put_smpaff_in_irqaction(action, CPU_MASK_NONE);

	*(bucket->pil + irq_action) = action;
	enable_irq(irq);

	spin_unlock_irqrestore(&irq_action_lock, flags);

#ifdef CONFIG_SMP
	distribute_irqs();
#endif
	return 0;
}

/* We really don't need these at all on the Sparc.  We only have
 * stubs here because they are exported to modules.
 */
unsigned long probe_irq_on(void)
{
	return 0;
}

EXPORT_SYMBOL(probe_irq_on);

int probe_irq_off(unsigned long mask)
{
	return 0;
}

EXPORT_SYMBOL(probe_irq_off);

#ifdef CONFIG_SMP
static int retarget_one_irq(struct irqaction *p, int goal_cpu)
{
	struct ino_bucket *bucket = get_ino_in_irqaction(p) + ivector_table;
	unsigned long imap = bucket->imap;
	unsigned int tid;

	while (!cpu_online(goal_cpu)) {
		if (++goal_cpu >= NR_CPUS)
			goal_cpu = 0;
	}

	if (tlb_type == cheetah || tlb_type == cheetah_plus) {
		tid = goal_cpu << 26;
		tid &= IMAP_AID_SAFARI;
	} else if (this_is_starfire == 0) {
		tid = goal_cpu << 26;
		tid &= IMAP_TID_UPA;
	} else {
		tid = (starfire_translate(imap, goal_cpu) << 26);
		tid &= IMAP_TID_UPA;
	}
	upa_writel(tid | IMAP_VALID, imap);

	while (!cpu_online(goal_cpu)) {
		if (++goal_cpu >= NR_CPUS)
			goal_cpu = 0;
	}

	return goal_cpu;
}

/* Called from request_irq. */
static void distribute_irqs(void)
{
	unsigned long flags;
	int cpu, level;

	spin_lock_irqsave(&irq_action_lock, flags);
	cpu = 0;

	/*
	 * Skip the timer at [0], and very rare error/power intrs at [15].
	 * Also level [12], it causes problems on Ex000 systems.
	 */
	for (level = 1; level < NR_IRQS; level++) {
		struct irqaction *p = irq_action[level];
		if (level == 12) continue;
		while(p) {
			cpu = retarget_one_irq(p, cpu);
			p = p->next;
		}
	}
	spin_unlock_irqrestore(&irq_action_lock, flags);
}
#endif


struct sun5_timer *prom_timers;
static u64 prom_limit0, prom_limit1;

static void map_prom_timers(void)
{
	unsigned int addr[3];
	int tnode, err;

	/* PROM timer node hangs out in the top level of device siblings... */
	tnode = prom_finddevice("/counter-timer");

	/* Assume if node is not present, PROM uses different tick mechanism
	 * which we should not care about.
	 */
	if (tnode == 0 || tnode == -1) {
		prom_timers = (struct sun5_timer *) 0;
		return;
	}

	/* If PROM is really using this, it must be mapped by him. */
	err = prom_getproperty(tnode, "address", (char *)addr, sizeof(addr));
	if (err == -1) {
		prom_printf("PROM does not have timer mapped, trying to continue.\n");
		prom_timers = (struct sun5_timer *) 0;
		return;
	}
	prom_timers = (struct sun5_timer *) ((unsigned long)addr[0]);
}

static void kill_prom_timer(void)
{
	if (!prom_timers)
		return;

	/* Save them away for later. */
	prom_limit0 = prom_timers->limit0;
	prom_limit1 = prom_timers->limit1;

	/* Just as in sun4c/sun4m PROM uses timer which ticks at IRQ 14.
	 * We turn both off here just to be paranoid.
	 */
	prom_timers->limit0 = 0;
	prom_timers->limit1 = 0;

	/* Wheee, eat the interrupt packet too... */
	__asm__ __volatile__(
"	mov	0x40, %%g2\n"
"	ldxa	[%%g0] %0, %%g1\n"
"	ldxa	[%%g2] %1, %%g1\n"
"	stxa	%%g0, [%%g0] %0\n"
"	membar	#Sync\n"
	: /* no outputs */
	: "i" (ASI_INTR_RECEIVE), "i" (ASI_INTR_R)
	: "g1", "g2");
}

void enable_prom_timer(void)
{
	if (!prom_timers)
		return;

	/* Set it to whatever was there before. */
	prom_timers->limit1 = prom_limit1;
	prom_timers->count1 = 0;
	prom_timers->limit0 = prom_limit0;
	prom_timers->count0 = 0;
}

void init_irqwork_curcpu(void)
{
	register struct irq_work_struct *workp asm("o2");
	unsigned long tmp;
	int cpu = hard_smp_processor_id();

	memset(__irq_work + cpu, 0, sizeof(*workp));

	/* Make sure we are called with PSTATE_IE disabled.  */
	__asm__ __volatile__("rdpr	%%pstate, %0\n\t"
			     : "=r" (tmp));
	if (tmp & PSTATE_IE) {
		prom_printf("BUG: init_irqwork_curcpu() called with "
			    "PSTATE_IE enabled, bailing.\n");
		__asm__ __volatile__("mov	%%i7, %0\n\t"
				     : "=r" (tmp));
		prom_printf("BUG: Called from %lx\n", tmp);
		prom_halt();
	}

	/* Set interrupt globals.  */
	workp = &__irq_work[cpu];
	__asm__ __volatile__(
	"rdpr	%%pstate, %0\n\t"
	"wrpr	%0, %1, %%pstate\n\t"
	"mov	%2, %%g6\n\t"
	"wrpr	%0, 0x0, %%pstate\n\t"
	: "=&r" (tmp)
	: "i" (PSTATE_IG), "r" (workp));
}

/* Only invoked on boot processor. */
void __init init_IRQ(void)
{
	map_prom_timers();
	kill_prom_timer();
	memset(&ivector_table[0], 0, sizeof(ivector_table));

	/* We need to clear any IRQ's pending in the soft interrupt
	 * registers, a spurious one could be left around from the
	 * PROM timer which we just disabled.
	 */
	clear_softint(get_softint());

	/* Now that ivector table is initialized, it is safe
	 * to receive IRQ vector traps.  We will normally take
	 * one or two right now, in case some device PROM used
	 * to boot us wants to speak to us.  We just ignore them.
	 */
	__asm__ __volatile__("rdpr	%%pstate, %%g1\n\t"
			     "or	%%g1, %0, %%g1\n\t"
			     "wrpr	%%g1, 0x0, %%pstate"
			     : /* No outputs */
			     : "i" (PSTATE_IE)
			     : "g1");
}

static struct proc_dir_entry * root_irq_dir;
static struct proc_dir_entry * irq_dir [NUM_IVECS];

#ifdef CONFIG_SMP

static int irq_affinity_read_proc (char *page, char **start, off_t off,
			int count, int *eof, void *data)
{
	struct ino_bucket *bp = ivector_table + (long)data;
	struct irqaction *ap = bp->irq_info;
	cpumask_t mask;
	int len;

	mask = get_smpaff_in_irqaction(ap);
	if (cpus_empty(mask))
		mask = cpu_online_map;

	len = cpumask_scnprintf(page, count, mask);
	if (count - len < 2)
		return -EINVAL;
	len += sprintf(page + len, "\n");
	return len;
}

static inline void set_intr_affinity(int irq, cpumask_t hw_aff)
{
	struct ino_bucket *bp = ivector_table + irq;

	/* Users specify affinity in terms of hw cpu ids.
	 * As soon as we do this, handler_irq() might see and take action.
	 */
	put_smpaff_in_irqaction((struct irqaction *)bp->irq_info, hw_aff);

	/* Migration is simply done by the next cpu to service this
	 * interrupt.
	 */
}

static int irq_affinity_write_proc (struct file *file, const char __user *buffer,
					unsigned long count, void *data)
{
	int irq = (long) data, full_count = count, err;
	cpumask_t new_value;

	err = cpumask_parse(buffer, count, new_value);

	/*
	 * 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.
	 */
	cpus_and(new_value, new_value, cpu_online_map);
	if (cpus_empty(new_value))
		return -EINVAL;

	set_intr_affinity(irq, new_value);

	return full_count;
}

#endif

#define MAX_NAMELEN 10

static void register_irq_proc (unsigned int irq)
{
	char name [MAX_NAMELEN];

	if (!root_irq_dir || irq_dir[irq])
		return;

	memset(name, 0, MAX_NAMELEN);
	sprintf(name, "%x", irq);

	/* create /proc/irq/1234 */
	irq_dir[irq] = proc_mkdir(name, root_irq_dir);

#ifdef CONFIG_SMP
	/* XXX SMP affinity not supported on starfire yet. */
	if (this_is_starfire == 0) {
		struct proc_dir_entry *entry;

		/* create /proc/irq/1234/smp_affinity */
		entry = create_proc_entry("smp_affinity", 0600, irq_dir[irq]);

		if (entry) {
			entry->nlink = 1;
			entry->data = (void *)(long)irq;
			entry->read_proc = irq_affinity_read_proc;
			entry->write_proc = irq_affinity_write_proc;
		}
	}
#endif
}

void init_irq_proc (void)
{
	/* create /proc/irq */
	root_irq_dir = proc_mkdir("irq", NULL);
}