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authorGrant Likely <grant.likely@secretlab.ca>2012-02-16 01:37:49 -0700
committerGrant Likely <grant.likely@secretlab.ca>2012-02-16 01:37:49 -0700
commitcc79ca691c292e9fd44f589c7940b9654e22f2f6 (patch)
tree4efe01e4f4a92f97dba326923e0a7a8af4b3bf87 /arch/powerpc
parent6d9285b00f776eebe459a858ebf07b56c36c60d2 (diff)
irq_domain: Move irq_domain code from powerpc to kernel/irq
This patch only moves the code. It doesn't make any changes, and the code is still only compiled for powerpc. Follow-on patches will generalize the code for other architectures. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Milton Miller <miltonm@bga.com> Tested-by: Olof Johansson <olof@lixom.net>
Diffstat (limited to 'arch/powerpc')
-rw-r--r--arch/powerpc/Kconfig1
-rw-r--r--arch/powerpc/include/asm/irq.h144
-rw-r--r--arch/powerpc/kernel/irq.c502
3 files changed, 1 insertions, 646 deletions
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 1919634a9b3..303703d716f 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -135,6 +135,7 @@ config PPC
select HAVE_GENERIC_HARDIRQS
select HAVE_SPARSE_IRQ
select IRQ_PER_CPU
+ select IRQ_DOMAIN
select GENERIC_IRQ_SHOW
select GENERIC_IRQ_SHOW_LEVEL
select IRQ_FORCED_THREADING
diff --git a/arch/powerpc/include/asm/irq.h b/arch/powerpc/include/asm/irq.h
index f80f262e059..728cc30d04e 100644
--- a/arch/powerpc/include/asm/irq.h
+++ b/arch/powerpc/include/asm/irq.h
@@ -42,155 +42,11 @@ extern atomic_t ppc_n_lost_interrupts;
/* Same thing, used by the generic IRQ code */
#define NR_IRQS_LEGACY NUM_ISA_INTERRUPTS
-/*
- * The host code and data structures are fairly agnostic to the fact that
- * we use an open firmware device-tree. We do have references to struct
- * device_node in two places: in irq_find_host() to find the host matching
- * a given interrupt controller node, and of course as an argument to its
- * counterpart host->ops->match() callback. However, those are treated as
- * generic pointers by the core and the fact that it's actually a device-node
- * pointer is purely a convention between callers and implementation. This
- * code could thus be used on other architectures by replacing those two
- * by some sort of arch-specific void * "token" used to identify interrupt
- * controllers.
- */
-
struct irq_data;
extern irq_hw_number_t irqd_to_hwirq(struct irq_data *d);
extern irq_hw_number_t virq_to_hw(unsigned int virq);
/**
- * irq_alloc_host - Allocate a new irq_domain data structure
- * @of_node: optional device-tree node of the interrupt controller
- * @revmap_type: type of reverse mapping to use
- * @revmap_arg: for IRQ_DOMAIN_MAP_LINEAR linear only: size of the map
- * @ops: map/unmap host callbacks
- * @inval_irq: provide a hw number in that host space that is always invalid
- *
- * Allocates and initialize and irq_domain structure. Note that in the case of
- * IRQ_DOMAIN_MAP_LEGACY, the map() callback will be called before this returns
- * for all legacy interrupts except 0 (which is always the invalid irq for
- * a legacy controller). For a IRQ_DOMAIN_MAP_LINEAR, the map is allocated by
- * this call as well. For a IRQ_DOMAIN_MAP_TREE, the radix tree will be allocated
- * later during boot automatically (the reverse mapping will use the slow path
- * until that happens).
- */
-extern struct irq_domain *irq_alloc_host(struct device_node *of_node,
- unsigned int revmap_type,
- unsigned int revmap_arg,
- struct irq_domain_ops *ops,
- irq_hw_number_t inval_irq);
-
-
-/**
- * irq_find_host - Locates a host for a given device node
- * @node: device-tree node of the interrupt controller
- */
-extern struct irq_domain *irq_find_host(struct device_node *node);
-
-
-/**
- * irq_set_default_host - Set a "default" host
- * @host: default host pointer
- *
- * For convenience, it's possible to set a "default" host that will be used
- * whenever NULL is passed to irq_create_mapping(). It makes life easier for
- * platforms that want to manipulate a few hard coded interrupt numbers that
- * aren't properly represented in the device-tree.
- */
-extern void irq_set_default_host(struct irq_domain *host);
-
-
-/**
- * irq_set_virq_count - Set the maximum number of virt irqs
- * @count: number of linux virtual irqs, capped with NR_IRQS
- *
- * This is mainly for use by platforms like iSeries who want to program
- * the virtual irq number in the controller to avoid the reverse mapping
- */
-extern void irq_set_virq_count(unsigned int count);
-
-
-/**
- * irq_create_mapping - Map a hardware interrupt into linux virq space
- * @host: host owning this hardware interrupt or NULL for default host
- * @hwirq: hardware irq number in that host space
- *
- * Only one mapping per hardware interrupt is permitted. Returns a linux
- * virq number.
- * If the sense/trigger is to be specified, set_irq_type() should be called
- * on the number returned from that call.
- */
-extern unsigned int irq_create_mapping(struct irq_domain *host,
- irq_hw_number_t hwirq);
-
-
-/**
- * irq_dispose_mapping - Unmap an interrupt
- * @virq: linux virq number of the interrupt to unmap
- */
-extern void irq_dispose_mapping(unsigned int virq);
-
-/**
- * irq_find_mapping - Find a linux virq from an hw irq number.
- * @host: host owning this hardware interrupt
- * @hwirq: hardware irq number in that host space
- *
- * This is a slow path, for use by generic code. It's expected that an
- * irq controller implementation directly calls the appropriate low level
- * mapping function.
- */
-extern unsigned int irq_find_mapping(struct irq_domain *host,
- irq_hw_number_t hwirq);
-
-/**
- * irq_create_direct_mapping - Allocate a virq for direct mapping
- * @host: host to allocate the virq for or NULL for default host
- *
- * This routine is used for irq controllers which can choose the hardware
- * interrupt numbers they generate. In such a case it's simplest to use
- * the linux virq as the hardware interrupt number.
- */
-extern unsigned int irq_create_direct_mapping(struct irq_domain *host);
-
-/**
- * irq_radix_revmap_insert - Insert a hw irq to linux virq number mapping.
- * @host: host owning this hardware interrupt
- * @virq: linux irq number
- * @hwirq: hardware irq number in that host space
- *
- * This is for use by irq controllers that use a radix tree reverse
- * mapping for fast lookup.
- */
-extern void irq_radix_revmap_insert(struct irq_domain *host, unsigned int virq,
- irq_hw_number_t hwirq);
-
-/**
- * irq_radix_revmap_lookup - Find a linux virq from a hw irq number.
- * @host: host owning this hardware interrupt
- * @hwirq: hardware irq number in that host space
- *
- * This is a fast path, for use by irq controller code that uses radix tree
- * revmaps
- */
-extern unsigned int irq_radix_revmap_lookup(struct irq_domain *host,
- irq_hw_number_t hwirq);
-
-/**
- * irq_linear_revmap - Find a linux virq from a hw irq number.
- * @host: host owning this hardware interrupt
- * @hwirq: hardware irq number in that host space
- *
- * This is a fast path, for use by irq controller code that uses linear
- * revmaps. It does fallback to the slow path if the revmap doesn't exist
- * yet and will create the revmap entry with appropriate locking
- */
-
-extern unsigned int irq_linear_revmap(struct irq_domain *host,
- irq_hw_number_t hwirq);
-
-
-/**
* irq_early_init - Init irq remapping subsystem
*/
extern void irq_early_init(void);
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
index 269fbd5ac62..e3673ff6b7a 100644
--- a/arch/powerpc/kernel/irq.c
+++ b/arch/powerpc/kernel/irq.c
@@ -486,17 +486,6 @@ void do_softirq(void)
local_irq_restore(flags);
}
-
-/*
- * IRQ controller and virtual interrupts
- */
-
-static LIST_HEAD(irq_domain_list);
-static DEFINE_MUTEX(irq_domain_mutex);
-static DEFINE_MUTEX(revmap_trees_mutex);
-static unsigned int irq_virq_count = NR_IRQS;
-static struct irq_domain *irq_default_host;
-
irq_hw_number_t irqd_to_hwirq(struct irq_data *d)
{
return d->hwirq;
@@ -510,362 +499,6 @@ irq_hw_number_t virq_to_hw(unsigned int virq)
}
EXPORT_SYMBOL_GPL(virq_to_hw);
-static int default_irq_host_match(struct irq_domain *h, struct device_node *np)
-{
- return h->of_node != NULL && h->of_node == np;
-}
-
-struct irq_domain *irq_alloc_host(struct device_node *of_node,
- unsigned int revmap_type,
- unsigned int revmap_arg,
- struct irq_domain_ops *ops,
- irq_hw_number_t inval_irq)
-{
- struct irq_domain *host, *h;
- unsigned int size = sizeof(struct irq_domain);
- unsigned int i;
- unsigned int *rmap;
-
- /* Allocate structure and revmap table if using linear mapping */
- if (revmap_type == IRQ_DOMAIN_MAP_LINEAR)
- size += revmap_arg * sizeof(unsigned int);
- host = kzalloc(size, GFP_KERNEL);
- if (host == NULL)
- return NULL;
-
- /* Fill structure */
- host->revmap_type = revmap_type;
- host->inval_irq = inval_irq;
- host->ops = ops;
- host->of_node = of_node_get(of_node);
-
- if (host->ops->match == NULL)
- host->ops->match = default_irq_host_match;
-
- mutex_lock(&irq_domain_mutex);
- /* Make sure only one legacy controller can be created */
- if (revmap_type == IRQ_DOMAIN_MAP_LEGACY) {
- list_for_each_entry(h, &irq_domain_list, link) {
- if (WARN_ON(h->revmap_type == IRQ_DOMAIN_MAP_LEGACY)) {
- mutex_unlock(&irq_domain_mutex);
- of_node_put(host->of_node);
- kfree(host);
- return NULL;
- }
- }
- }
- list_add(&host->link, &irq_domain_list);
- mutex_unlock(&irq_domain_mutex);
-
- /* Additional setups per revmap type */
- switch(revmap_type) {
- case IRQ_DOMAIN_MAP_LEGACY:
- /* 0 is always the invalid number for legacy */
- host->inval_irq = 0;
- /* setup us as the host for all legacy interrupts */
- for (i = 1; i < NUM_ISA_INTERRUPTS; i++) {
- struct irq_data *irq_data = irq_get_irq_data(i);
- irq_data->hwirq = i;
- irq_data->domain = host;
-
- /* Legacy flags are left to default at this point,
- * one can then use irq_create_mapping() to
- * explicitly change them
- */
- ops->map(host, i, i);
-
- /* Clear norequest flags */
- irq_clear_status_flags(i, IRQ_NOREQUEST);
- }
- break;
- case IRQ_DOMAIN_MAP_LINEAR:
- rmap = (unsigned int *)(host + 1);
- for (i = 0; i < revmap_arg; i++)
- rmap[i] = NO_IRQ;
- host->revmap_data.linear.size = revmap_arg;
- host->revmap_data.linear.revmap = rmap;
- break;
- case IRQ_DOMAIN_MAP_TREE:
- INIT_RADIX_TREE(&host->revmap_data.tree, GFP_KERNEL);
- break;
- default:
- break;
- }
-
- pr_debug("irq: Allocated host of type %d @0x%p\n", revmap_type, host);
-
- return host;
-}
-
-struct irq_domain *irq_find_host(struct device_node *node)
-{
- struct irq_domain *h, *found = NULL;
-
- /* We might want to match the legacy controller last since
- * it might potentially be set to match all interrupts in
- * the absence of a device node. This isn't a problem so far
- * yet though...
- */
- mutex_lock(&irq_domain_mutex);
- list_for_each_entry(h, &irq_domain_list, link)
- if (h->ops->match(h, node)) {
- found = h;
- break;
- }
- mutex_unlock(&irq_domain_mutex);
- return found;
-}
-EXPORT_SYMBOL_GPL(irq_find_host);
-
-void irq_set_default_host(struct irq_domain *host)
-{
- pr_debug("irq: Default host set to @0x%p\n", host);
-
- irq_default_host = host;
-}
-
-void irq_set_virq_count(unsigned int count)
-{
- pr_debug("irq: Trying to set virq count to %d\n", count);
-
- BUG_ON(count < NUM_ISA_INTERRUPTS);
- if (count < NR_IRQS)
- irq_virq_count = count;
-}
-
-static int irq_setup_virq(struct irq_domain *host, unsigned int virq,
- irq_hw_number_t hwirq)
-{
- struct irq_data *irq_data = irq_get_irq_data(virq);
-
- irq_data->hwirq = hwirq;
- irq_data->domain = host;
- if (host->ops->map(host, virq, hwirq)) {
- pr_debug("irq: -> mapping failed, freeing\n");
- irq_data->domain = NULL;
- irq_data->hwirq = 0;
- return -1;
- }
-
- irq_clear_status_flags(virq, IRQ_NOREQUEST);
-
- return 0;
-}
-
-unsigned int irq_create_direct_mapping(struct irq_domain *host)
-{
- unsigned int virq;
-
- if (host == NULL)
- host = irq_default_host;
-
- BUG_ON(host == NULL);
- WARN_ON(host->revmap_type != IRQ_DOMAIN_MAP_NOMAP);
-
- virq = irq_alloc_desc_from(1, 0);
- if (virq == NO_IRQ) {
- pr_debug("irq: create_direct virq allocation failed\n");
- return NO_IRQ;
- }
- if (virq >= irq_virq_count) {
- pr_err("ERROR: no free irqs available below %i maximum\n",
- irq_virq_count);
- irq_free_desc(virq);
- return 0;
- }
-
- pr_debug("irq: create_direct obtained virq %d\n", virq);
-
- if (irq_setup_virq(host, virq, virq)) {
- irq_free_desc(virq);
- return NO_IRQ;
- }
-
- return virq;
-}
-
-unsigned int irq_create_mapping(struct irq_domain *host,
- irq_hw_number_t hwirq)
-{
- unsigned int virq, hint;
-
- pr_debug("irq: irq_create_mapping(0x%p, 0x%lx)\n", host, hwirq);
-
- /* Look for default host if nececssary */
- if (host == NULL)
- host = irq_default_host;
- if (host == NULL) {
- printk(KERN_WARNING "irq_create_mapping called for"
- " NULL host, hwirq=%lx\n", hwirq);
- WARN_ON(1);
- return NO_IRQ;
- }
- pr_debug("irq: -> using host @%p\n", host);
-
- /* Check if mapping already exists */
- virq = irq_find_mapping(host, hwirq);
- if (virq != NO_IRQ) {
- pr_debug("irq: -> existing mapping on virq %d\n", virq);
- return virq;
- }
-
- /* Get a virtual interrupt number */
- if (host->revmap_type == IRQ_DOMAIN_MAP_LEGACY) {
- /* Handle legacy */
- virq = (unsigned int)hwirq;
- if (virq == 0 || virq >= NUM_ISA_INTERRUPTS)
- return NO_IRQ;
- return virq;
- } else {
- /* Allocate a virtual interrupt number */
- hint = hwirq % irq_virq_count;
- if (hint == 0)
- hint = 1;
- virq = irq_alloc_desc_from(hint, 0);
- if (!virq)
- virq = irq_alloc_desc_from(1, 0);
- if (virq == NO_IRQ) {
- pr_debug("irq: -> virq allocation failed\n");
- return NO_IRQ;
- }
- }
-
- if (irq_setup_virq(host, virq, hwirq)) {
- if (host->revmap_type != IRQ_DOMAIN_MAP_LEGACY)
- irq_free_desc(virq);
- return NO_IRQ;
- }
-
- pr_debug("irq: irq %lu on host %s mapped to virtual irq %u\n",
- hwirq, host->of_node ? host->of_node->full_name : "null", virq);
-
- return virq;
-}
-EXPORT_SYMBOL_GPL(irq_create_mapping);
-
-unsigned int irq_create_of_mapping(struct device_node *controller,
- const u32 *intspec, unsigned int intsize)
-{
- struct irq_domain *host;
- irq_hw_number_t hwirq;
- unsigned int type = IRQ_TYPE_NONE;
- unsigned int virq;
-
- if (controller == NULL)
- host = irq_default_host;
- else
- host = irq_find_host(controller);
- if (host == NULL) {
- printk(KERN_WARNING "irq: no irq host found for %s !\n",
- controller->full_name);
- return NO_IRQ;
- }
-
- /* If host has no translation, then we assume interrupt line */
- if (host->ops->xlate == NULL)
- hwirq = intspec[0];
- else {
- if (host->ops->xlate(host, controller, intspec, intsize,
- &hwirq, &type))
- return NO_IRQ;
- }
-
- /* Create mapping */
- virq = irq_create_mapping(host, hwirq);
- if (virq == NO_IRQ)
- return virq;
-
- /* Set type if specified and different than the current one */
- if (type != IRQ_TYPE_NONE &&
- type != (irqd_get_trigger_type(irq_get_irq_data(virq))))
- irq_set_irq_type(virq, type);
- return virq;
-}
-EXPORT_SYMBOL_GPL(irq_create_of_mapping);
-
-void irq_dispose_mapping(unsigned int virq)
-{
- struct irq_data *irq_data = irq_get_irq_data(virq);
- struct irq_domain *host;
- irq_hw_number_t hwirq;
-
- if (virq == NO_IRQ || !irq_data)
- return;
-
- host = irq_data->domain;
- if (WARN_ON(host == NULL))
- return;
-
- /* Never unmap legacy interrupts */
- if (host->revmap_type == IRQ_DOMAIN_MAP_LEGACY)
- return;
-
- irq_set_status_flags(virq, IRQ_NOREQUEST);
-
- /* remove chip and handler */
- irq_set_chip_and_handler(virq, NULL, NULL);
-
- /* Make sure it's completed */
- synchronize_irq(virq);
-
- /* Tell the PIC about it */
- if (host->ops->unmap)
- host->ops->unmap(host, virq);
- smp_mb();
-
- /* Clear reverse map */
- hwirq = irq_data->hwirq;
- switch(host->revmap_type) {
- case IRQ_DOMAIN_MAP_LINEAR:
- if (hwirq < host->revmap_data.linear.size)
- host->revmap_data.linear.revmap[hwirq] = NO_IRQ;
- break;
- case IRQ_DOMAIN_MAP_TREE:
- mutex_lock(&revmap_trees_mutex);
- radix_tree_delete(&host->revmap_data.tree, hwirq);
- mutex_unlock(&revmap_trees_mutex);
- break;
- }
-
- /* Destroy map */
- irq_data->hwirq = host->inval_irq;
-
- irq_free_desc(virq);
-}
-EXPORT_SYMBOL_GPL(irq_dispose_mapping);
-
-unsigned int irq_find_mapping(struct irq_domain *host,
- irq_hw_number_t hwirq)
-{
- unsigned int i;
- unsigned int hint = hwirq % irq_virq_count;
-
- /* Look for default host if nececssary */
- if (host == NULL)
- host = irq_default_host;
- if (host == NULL)
- return NO_IRQ;
-
- /* legacy -> bail early */
- if (host->revmap_type == IRQ_DOMAIN_MAP_LEGACY)
- return hwirq;
-
- /* Slow path does a linear search of the map */
- if (hint == 0)
- hint = 1;
- i = hint;
- do {
- struct irq_data *data = irq_get_irq_data(i);
- if (data && (data->domain == host) && (data->hwirq == hwirq))
- return i;
- i++;
- if (i >= irq_virq_count)
- i = 1;
- } while(i != hint);
- return NO_IRQ;
-}
-EXPORT_SYMBOL_GPL(irq_find_mapping);
-
#ifdef CONFIG_SMP
int irq_choose_cpu(const struct cpumask *mask)
{
@@ -902,146 +535,11 @@ int irq_choose_cpu(const struct cpumask *mask)
}
#endif
-unsigned int irq_radix_revmap_lookup(struct irq_domain *host,
- irq_hw_number_t hwirq)
-{
- struct irq_data *irq_data;
-
- if (WARN_ON_ONCE(host->revmap_type != IRQ_DOMAIN_MAP_TREE))
- return irq_find_mapping(host, hwirq);
-
- /*
- * Freeing an irq can delete nodes along the path to
- * do the lookup via call_rcu.
- */
- rcu_read_lock();
- irq_data = radix_tree_lookup(&host->revmap_data.tree, hwirq);
- rcu_read_unlock();
-
- /*
- * If found in radix tree, then fine.
- * Else fallback to linear lookup - this should not happen in practice
- * as it means that we failed to insert the node in the radix tree.
- */
- return irq_data ? irq_data->irq : irq_find_mapping(host, hwirq);
-}
-
-void irq_radix_revmap_insert(struct irq_domain *host, unsigned int virq,
- irq_hw_number_t hwirq)
-{
- struct irq_data *irq_data = irq_get_irq_data(virq);
-
- if (WARN_ON(host->revmap_type != IRQ_DOMAIN_MAP_TREE))
- return;
-
- if (virq != NO_IRQ) {
- mutex_lock(&revmap_trees_mutex);
- radix_tree_insert(&host->revmap_data.tree, hwirq, irq_data);
- mutex_unlock(&revmap_trees_mutex);
- }
-}
-
-unsigned int irq_linear_revmap(struct irq_domain *host,
- irq_hw_number_t hwirq)
-{
- unsigned int *revmap;
-
- if (WARN_ON_ONCE(host->revmap_type != IRQ_DOMAIN_MAP_LINEAR))
- return irq_find_mapping(host, hwirq);
-
- /* Check revmap bounds */
- if (unlikely(hwirq >= host->revmap_data.linear.size))
- return irq_find_mapping(host, hwirq);
-
- /* Check if revmap was allocated */
- revmap = host->revmap_data.linear.revmap;
- if (unlikely(revmap == NULL))
- return irq_find_mapping(host, hwirq);
-
- /* Fill up revmap with slow path if no mapping found */
- if (unlikely(revmap[hwirq] == NO_IRQ))
- revmap[hwirq] = irq_find_mapping(host, hwirq);
-
- return revmap[hwirq];
-}
-
int arch_early_irq_init(void)
{
return 0;
}
-#ifdef CONFIG_VIRQ_DEBUG
-static int virq_debug_show(struct seq_file *m, void *private)
-{
- unsigned long flags;
- struct irq_desc *desc;
- const char *p;
- static const char none[] = "none";
- void *data;
- int i;
-
- seq_printf(m, "%-5s %-7s %-15s %-18s %s\n", "virq", "hwirq",
- "chip name", "chip data", "host name");
-
- for (i = 1; i < nr_irqs; i++) {
- desc = irq_to_desc(i);
- if (!desc)
- continue;
-
- raw_spin_lock_irqsave(&desc->lock, flags);
-
- if (desc->action && desc->action->handler) {
- struct irq_chip *chip;
-
- seq_printf(m, "%5d ", i);
- seq_printf(m, "0x%05lx ", desc->irq_data.hwirq);
-
- chip = irq_desc_get_chip(desc);
- if (chip && chip->name)
- p = chip->name;
- else
- p = none;
- seq_printf(m, "%-15s ", p);
-
- data = irq_desc_get_chip_data(desc);
- seq_printf(m, "0x%16p ", data);
-
- if (desc->irq_data.domain->of_node)
- p = desc->irq_data.domain->of_node->full_name;
- else
- p = none;
- seq_printf(m, "%s\n", p);
- }
-
- raw_spin_unlock_irqrestore(&desc->lock, flags);
- }
-
- return 0;
-}
-
-static int virq_debug_open(struct inode *inode, struct file *file)
-{
- return single_open(file, virq_debug_show, inode->i_private);
-}
-
-static const struct file_operations virq_debug_fops = {
- .open = virq_debug_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
-};
-
-static int __init irq_debugfs_init(void)
-{
- if (debugfs_create_file("virq_mapping", S_IRUGO, powerpc_debugfs_root,
- NULL, &virq_debug_fops) == NULL)
- return -ENOMEM;
-
- return 0;
-}
-__initcall(irq_debugfs_init);
-#endif /* CONFIG_VIRQ_DEBUG */
-
#ifdef CONFIG_PPC64
static int __init setup_noirqdistrib(char *str)
{