irq_domain/c6x: Convert c6x to use generic irq_domain support.

The C6X IRQ support was copied almost verbatim from the PowerPC virtual IRQ
code. The PowerPC code was used as the basis for generic irq_domain support,
so this patch mostly copies what what done to arch/powerpc by Grant Likely
in his irq_domain patch series.

Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 13 insertions, 598 deletions

diff --git a/arch/c6x/kernel/irq.c b/arch/c6x/kernel/irq.c
index 0929e4b2b244..3d5ac600a38b 100644
--- a/arch/c6x/kernel/irq.c
+++ b/arch/c6x/kernel/irq.c
@@ -73,10 +73,10 @@ asmlinkage void c6x_do_IRQ(unsigned int prio, struct pt_regs *regs)
         set_irq_regs(old_regs);
 }
 
-static struct irq_host *core_host;
+static struct irq_domain *core_domain;
 
-static int core_host_map(struct irq_host *h, unsigned int virq,
-                         irq_hw_number_t hw)
+static int core_domain_map(struct irq_domain *h, unsigned int virq,
+                           irq_hw_number_t hw)
 {
         if (hw < 4 || hw >= NR_PRIORITY_IRQS)
                 return -EINVAL;
@@ -86,8 +86,8 @@ static int core_host_map(struct irq_host *h, unsigned int virq,
         return 0;
 }
 
-static struct irq_host_ops core_host_ops = {
-        .map = core_host_map,
+static struct irq_domain_ops core_domain_ops = {
+        .map = core_domain_map,
 };
 
 void __init init_IRQ(void)
@@ -100,10 +100,11 @@ void __init init_IRQ(void)
         np = of_find_compatible_node(NULL, NULL, "ti,c64x+core-pic");
         if (np != NULL) {
                 /* create the core host */
-                core_host = irq_alloc_host(np, IRQ_HOST_MAP_PRIORITY, 0,
-                                           &core_host_ops, 0);
-                if (core_host)
-                        irq_set_default_host(core_host);
+                core_domain = irq_domain_add_legacy(np, NR_PRIORITY_IRQS,
+                                                    0, 0, &core_domain_ops,
+                                                    NULL);
+                if (core_domain)
+                        irq_set_default_host(core_domain);
                 of_node_put(np);
         }
 
@@ -128,601 +129,15 @@ int arch_show_interrupts(struct seq_file *p, int prec)
         return 0;
 }
 
-/*
- * IRQ controller and virtual interrupts
- */
-
-/* The main irq map itself is an array of NR_IRQ entries containing the
- * associate host and irq number. An entry with a host of NULL is free.
- * An entry can be allocated if it's free, the allocator always then sets
- * hwirq first to the host's invalid irq number and then fills ops.
- */
-struct irq_map_entry {
-        irq_hw_number_t hwirq;
-        struct irq_host *host;
-};
-
-static LIST_HEAD(irq_hosts);
-static DEFINE_RAW_SPINLOCK(irq_big_lock);
-static DEFINE_MUTEX(revmap_trees_mutex);
-static struct irq_map_entry irq_map[NR_IRQS];
-static unsigned int irq_virq_count = NR_IRQS;
-static struct irq_host *irq_default_host;
-
 irq_hw_number_t irqd_to_hwirq(struct irq_data *d)
 {
-        return irq_map[d->irq].hwirq;
+        return d->hwirq;
 }
 EXPORT_SYMBOL_GPL(irqd_to_hwirq);
 
 irq_hw_number_t virq_to_hw(unsigned int virq)
 {
-        return irq_map[virq].hwirq;
+        struct irq_data *irq_data = irq_get_irq_data(virq);
+        return WARN_ON(!irq_data) ? 0 : irq_data->hwirq;
 }
 EXPORT_SYMBOL_GPL(virq_to_hw);
-
-bool virq_is_host(unsigned int virq, struct irq_host *host)
-{
-        return irq_map[virq].host == host;
-}
-EXPORT_SYMBOL_GPL(virq_is_host);
-
-static int default_irq_host_match(struct irq_host *h, struct device_node *np)
-{
-        return h->of_node != NULL && h->of_node == np;
-}
-
-struct irq_host *irq_alloc_host(struct device_node *of_node,
-                                unsigned int revmap_type,
-                                unsigned int revmap_arg,
-                                struct irq_host_ops *ops,
-                                irq_hw_number_t inval_irq)
-{
-        struct irq_host *host;
-        unsigned int size = sizeof(struct irq_host);
-        unsigned int i;
-        unsigned int *rmap;
-        unsigned long flags;
-
-        /* Allocate structure and revmap table if using linear mapping */
-        if (revmap_type == IRQ_HOST_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;
-
-        raw_spin_lock_irqsave(&irq_big_lock, flags);
-
-        /* Check for the priority controller. */
-        if (revmap_type == IRQ_HOST_MAP_PRIORITY) {
-                if (irq_map[0].host != NULL) {
-                        raw_spin_unlock_irqrestore(&irq_big_lock, flags);
-                        of_node_put(host->of_node);
-                        kfree(host);
-                        return NULL;
-                }
-                irq_map[0].host = host;
-        }
-
-        list_add(&host->link, &irq_hosts);
-        raw_spin_unlock_irqrestore(&irq_big_lock, flags);
-
-        /* Additional setups per revmap type */
-        switch (revmap_type) {
-        case IRQ_HOST_MAP_PRIORITY:
-                /* 0 is always the invalid number for priority */
-                host->inval_irq = 0;
-                /* setup us as the host for all priority interrupts */
-                for (i = 1; i < NR_PRIORITY_IRQS; i++) {
-                        irq_map[i].hwirq = i;
-                        smp_wmb();
-                        irq_map[i].host = host;
-                        smp_wmb();
-
-                        ops->map(host, i, i);
-                }
-                break;
-        case IRQ_HOST_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;
-                smp_wmb();
-                host->revmap_data.linear.revmap = rmap;
-                break;
-        case IRQ_HOST_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_host *irq_find_host(struct device_node *node)
-{
-        struct irq_host *h, *found = NULL;
-        unsigned long flags;
-
-        /* 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...
-         */
-        raw_spin_lock_irqsave(&irq_big_lock, flags);
-        list_for_each_entry(h, &irq_hosts, link)
-                if (h->ops->match(h, node)) {
-                        found = h;
-                        break;
-                }
-        raw_spin_unlock_irqrestore(&irq_big_lock, flags);
-        return found;
-}
-EXPORT_SYMBOL_GPL(irq_find_host);
-
-void irq_set_default_host(struct irq_host *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 < NR_PRIORITY_IRQS);
-        if (count < NR_IRQS)
-                irq_virq_count = count;
-}
-
-static int irq_setup_virq(struct irq_host *host, unsigned int virq,
-                            irq_hw_number_t hwirq)
-{
-        int res;
-
-        res = irq_alloc_desc_at(virq, 0);
-        if (res != virq) {
-                pr_debug("irq: -> allocating desc failed\n");
-                goto error;
-        }
-
-        /* map it */
-        smp_wmb();
-        irq_map[virq].hwirq = hwirq;
-        smp_mb();
-
-        if (host->ops->map(host, virq, hwirq)) {
-                pr_debug("irq: -> mapping failed, freeing\n");
-                goto errdesc;
-        }
-
-        irq_clear_status_flags(virq, IRQ_NOREQUEST);
-
-        return 0;
-
-errdesc:
-        irq_free_descs(virq, 1);
-error:
-        irq_free_virt(virq, 1);
-        return -1;
-}
-
-unsigned int irq_create_direct_mapping(struct irq_host *host)
-{
-        unsigned int virq;
-
-        if (host == NULL)
-                host = irq_default_host;
-
-        BUG_ON(host == NULL);
-        WARN_ON(host->revmap_type != IRQ_HOST_MAP_NOMAP);
-
-        virq = irq_alloc_virt(host, 1, 0);
-        if (virq == NO_IRQ) {
-                pr_debug("irq: create_direct virq allocation failed\n");
-                return NO_IRQ;
-        }
-
-        pr_debug("irq: create_direct obtained virq %d\n", virq);
-
-        if (irq_setup_virq(host, virq, virq))
-                return NO_IRQ;
-
-        return virq;
-}
-
-unsigned int irq_create_mapping(struct irq_host *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;
-        }
-
-        /* Allocate a virtual interrupt number */
-        hint = hwirq % irq_virq_count;
-        virq = irq_alloc_virt(host, 1, hint);
-        if (virq == NO_IRQ) {
-                pr_debug("irq: -> virq allocation failed\n");
-                return NO_IRQ;
-        }
-
-        if (irq_setup_virq(host, virq, hwirq))
-                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_host *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_host *host;
-        irq_hw_number_t hwirq;
-
-        if (virq == NO_IRQ)
-                return;
-
-        /* Never unmap priority interrupts */
-        if (virq < NR_PRIORITY_IRQS)
-                return;
-
-        host = irq_map[virq].host;
-        if (WARN_ON(host == NULL))
-                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_map[virq].hwirq;
-        switch (host->revmap_type) {
-        case IRQ_HOST_MAP_LINEAR:
-                if (hwirq < host->revmap_data.linear.size)
-                        host->revmap_data.linear.revmap[hwirq] = NO_IRQ;
-                break;
-        case IRQ_HOST_MAP_TREE:
-                mutex_lock(&revmap_trees_mutex);
-                radix_tree_delete(&host->revmap_data.tree, hwirq);
-                mutex_unlock(&revmap_trees_mutex);
-                break;
-        }
-
-        /* Destroy map */
-        smp_mb();
-        irq_map[virq].hwirq = host->inval_irq;
-
-        irq_free_descs(virq, 1);
-        /* Free it */
-        irq_free_virt(virq, 1);
-}
-EXPORT_SYMBOL_GPL(irq_dispose_mapping);
-
-unsigned int irq_find_mapping(struct irq_host *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;
-
-        /* Slow path does a linear search of the map */
-        i = hint;
-        do  {
-                if (irq_map[i].host == host &&
-                    irq_map[i].hwirq == hwirq)
-                        return i;
-                i++;
-                if (i >= irq_virq_count)
-                        i = 4;
-        } while (i != hint);
-        return NO_IRQ;
-}
-EXPORT_SYMBOL_GPL(irq_find_mapping);
-
-unsigned int irq_radix_revmap_lookup(struct irq_host *host,
-                                     irq_hw_number_t hwirq)
-{
-        struct irq_map_entry *ptr;
-        unsigned int virq;
-
-        if (WARN_ON_ONCE(host->revmap_type != IRQ_HOST_MAP_TREE))
-                return irq_find_mapping(host, hwirq);
-
-        /*
-         * The ptr returned references the static global irq_map.
-         * but freeing an irq can delete nodes along the path to
-         * do the lookup via call_rcu.
-         */
-        rcu_read_lock();
-        ptr = 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.
-         */
-        if (ptr)
-                virq = ptr - irq_map;
-        else
-                virq = irq_find_mapping(host, hwirq);
-
-        return virq;
-}
-
-void irq_radix_revmap_insert(struct irq_host *host, unsigned int virq,
-                             irq_hw_number_t hwirq)
-{
-        if (WARN_ON(host->revmap_type != IRQ_HOST_MAP_TREE))
-                return;
-
-        if (virq != NO_IRQ) {
-                mutex_lock(&revmap_trees_mutex);
-                radix_tree_insert(&host->revmap_data.tree, hwirq,
-                                  &irq_map[virq]);
-                mutex_unlock(&revmap_trees_mutex);
-        }
-}
-
-unsigned int irq_linear_revmap(struct irq_host *host,
-                               irq_hw_number_t hwirq)
-{
-        unsigned int *revmap;
-
-        if (WARN_ON_ONCE(host->revmap_type != IRQ_HOST_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];
-}
-
-unsigned int irq_alloc_virt(struct irq_host *host,
-                            unsigned int count,
-                            unsigned int hint)
-{
-        unsigned long flags;
-        unsigned int i, j, found = NO_IRQ;
-
-        if (count == 0 || count > (irq_virq_count - NR_PRIORITY_IRQS))
-                return NO_IRQ;
-
-        raw_spin_lock_irqsave(&irq_big_lock, flags);
-
-        /* Use hint for 1 interrupt if any */
-        if (count == 1 && hint >= NR_PRIORITY_IRQS &&
-            hint < irq_virq_count && irq_map[hint].host == NULL) {
-                found = hint;
-                goto hint_found;
-        }
-
-        /* Look for count consecutive numbers in the allocatable
-         * (non-legacy) space
-         */
-        for (i = NR_PRIORITY_IRQS, j = 0; i < irq_virq_count; i++) {
-                if (irq_map[i].host != NULL)
-                        j = 0;
-                else
-                        j++;
-
-                if (j == count) {
-                        found = i - count + 1;
-                        break;
-                }
-        }
-        if (found == NO_IRQ) {
-                raw_spin_unlock_irqrestore(&irq_big_lock, flags);
-                return NO_IRQ;
-        }
- hint_found:
-        for (i = found; i < (found + count); i++) {
-                irq_map[i].hwirq = host->inval_irq;
-                smp_wmb();
-                irq_map[i].host = host;
-        }
-        raw_spin_unlock_irqrestore(&irq_big_lock, flags);
-        return found;
-}
-
-void irq_free_virt(unsigned int virq, unsigned int count)
-{
-        unsigned long flags;
-        unsigned int i;
-
-        WARN_ON(virq < NR_PRIORITY_IRQS);
-        WARN_ON(count == 0 || (virq + count) > irq_virq_count);
-
-        if (virq < NR_PRIORITY_IRQS) {
-                if (virq + count < NR_PRIORITY_IRQS)
-                        return;
-                count  -= NR_PRIORITY_IRQS - virq;
-                virq = NR_PRIORITY_IRQS;
-        }
-
-        if (count > irq_virq_count || virq > irq_virq_count - count) {
-                if (virq > irq_virq_count)
-                        return;
-                count = irq_virq_count - virq;
-        }
-
-        raw_spin_lock_irqsave(&irq_big_lock, flags);
-        for (i = virq; i < (virq + count); i++) {
-                struct irq_host *host;
-
-                host = irq_map[i].host;
-                irq_map[i].hwirq = host->inval_irq;
-                smp_wmb();
-                irq_map[i].host = NULL;
-        }
-        raw_spin_unlock_irqrestore(&irq_big_lock, flags);
-}
-
-#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  ", irq_map[i].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 (irq_map[i].host && irq_map[i].host->of_node)
-                                p = irq_map[i].host->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;
-}
-device_initcall(irq_debugfs_init);
-#endif /* CONFIG_VIRQ_DEBUG */