--- /dev/null
+/*
+ * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
+ * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
+ *
+ * This file contains the interrupt descriptor management code
+ *
+ * Detailed information is available in Documentation/DocBook/genericirq
+ *
+ */
+#include <linux/irq.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+#include <linux/radix-tree.h>
+#include <linux/bitmap.h>
+
+#include "internals.h"
+
+/*
+ * lockdep: we want to handle all irq_desc locks as a single lock-class:
+ */
+static struct lock_class_key irq_desc_lock_class;
+
+#if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_HARDIRQS)
+static void __init init_irq_default_affinity(void)
+{
+ alloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT);
+ cpumask_setall(irq_default_affinity);
+}
+#else
+static void __init init_irq_default_affinity(void)
+{
+}
+#endif
+
+#ifdef CONFIG_SMP
+static int alloc_masks(struct irq_desc *desc, gfp_t gfp, int node)
+{
+ if (!zalloc_cpumask_var_node(&desc->irq_data.affinity, gfp, node))
+ return -ENOMEM;
+
+#ifdef CONFIG_GENERIC_PENDING_IRQ
+ if (!zalloc_cpumask_var_node(&desc->pending_mask, gfp, node)) {
+ free_cpumask_var(desc->irq_data.affinity);
+ return -ENOMEM;
+ }
+#endif
+ return 0;
+}
+
+static void desc_smp_init(struct irq_desc *desc, int node)
+{
+ desc->irq_data.node = node;
+ cpumask_copy(desc->irq_data.affinity, irq_default_affinity);
+#ifdef CONFIG_GENERIC_PENDING_IRQ
+ cpumask_clear(desc->pending_mask);
+#endif
+}
+
+static inline int desc_node(struct irq_desc *desc)
+{
+ return desc->irq_data.node;
+}
+
+#else
+static inline int
+alloc_masks(struct irq_desc *desc, gfp_t gfp, int node) { return 0; }
+static inline void desc_smp_init(struct irq_desc *desc, int node) { }
+static inline int desc_node(struct irq_desc *desc) { return 0; }
+#endif
+
+static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node)
+{
+ int cpu;
+
+ desc->irq_data.irq = irq;
+ desc->irq_data.chip = &no_irq_chip;
+ desc->irq_data.chip_data = NULL;
+ desc->irq_data.handler_data = NULL;
+ desc->irq_data.msi_desc = NULL;
+ desc->status = IRQ_DEFAULT_INIT_FLAGS;
+ desc->handle_irq = handle_bad_irq;
+ desc->depth = 1;
+ desc->irq_count = 0;
+ desc->irqs_unhandled = 0;
+ desc->name = NULL;
+ for_each_possible_cpu(cpu)
+ *per_cpu_ptr(desc->kstat_irqs, cpu) = 0;
+ desc_smp_init(desc, node);
+}
+
+int nr_irqs = NR_IRQS;
+EXPORT_SYMBOL_GPL(nr_irqs);
+
+static DEFINE_MUTEX(sparse_irq_lock);
+static DECLARE_BITMAP(allocated_irqs, IRQ_BITMAP_BITS);
+
+#ifdef CONFIG_SPARSE_IRQ
+
+static RADIX_TREE(irq_desc_tree, GFP_KERNEL);
+
+static void irq_insert_desc(unsigned int irq, struct irq_desc *desc)
+{
+ radix_tree_insert(&irq_desc_tree, irq, desc);
+}
+
+struct irq_desc *irq_to_desc(unsigned int irq)
+{
+ return radix_tree_lookup(&irq_desc_tree, irq);
+}
+
+static void delete_irq_desc(unsigned int irq)
+{
+ radix_tree_delete(&irq_desc_tree, irq);
+}
+
+#ifdef CONFIG_SMP
+static void free_masks(struct irq_desc *desc)
+{
+#ifdef CONFIG_GENERIC_PENDING_IRQ
+ free_cpumask_var(desc->pending_mask);
+#endif
+ free_cpumask_var(desc->irq_data.affinity);
+}
+#else
+static inline void free_masks(struct irq_desc *desc) { }
+#endif
+
+static struct irq_desc *alloc_desc(int irq, int node)
+{
+ struct irq_desc *desc;
+ gfp_t gfp = GFP_KERNEL;
+
+ desc = kzalloc_node(sizeof(*desc), gfp, node);
+ if (!desc)
+ return NULL;
+ /* allocate based on nr_cpu_ids */
+ desc->kstat_irqs = alloc_percpu(unsigned int);
+ if (!desc->kstat_irqs)
+ goto err_desc;
+
+ if (alloc_masks(desc, gfp, node))
+ goto err_kstat;
+
+ raw_spin_lock_init(&desc->lock);
+ lockdep_set_class(&desc->lock, &irq_desc_lock_class);
+
+ desc_set_defaults(irq, desc, node);
+
+ return desc;
+
+err_kstat:
+ free_percpu(desc->kstat_irqs);
+err_desc:
+ kfree(desc);
+ return NULL;
+}
+
+static void free_desc(unsigned int irq)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+
+ unregister_irq_proc(irq, desc);
+
+ mutex_lock(&sparse_irq_lock);
+ delete_irq_desc(irq);
+ mutex_unlock(&sparse_irq_lock);
+
+ free_masks(desc);
+ free_percpu(desc->kstat_irqs);
+ kfree(desc);
+}
+
+static int alloc_descs(unsigned int start, unsigned int cnt, int node)
+{
+ struct irq_desc *desc;
+ int i;
+
+ for (i = 0; i < cnt; i++) {
+ desc = alloc_desc(start + i, node);
+ if (!desc)
+ goto err;
+ mutex_lock(&sparse_irq_lock);
+ irq_insert_desc(start + i, desc);
+ mutex_unlock(&sparse_irq_lock);
+ }
+ return start;
+
+err:
+ for (i--; i >= 0; i--)
+ free_desc(start + i);
+
+ mutex_lock(&sparse_irq_lock);
+ bitmap_clear(allocated_irqs, start, cnt);
+ mutex_unlock(&sparse_irq_lock);
+ return -ENOMEM;
+}
+
+struct irq_desc * __ref irq_to_desc_alloc_node(unsigned int irq, int node)
+{
+ int res = irq_alloc_descs(irq, irq, 1, node);
+
+ if (res == -EEXIST || res == irq)
+ return irq_to_desc(irq);
+ return NULL;
+}
+
+int __init early_irq_init(void)
+{
+ int i, initcnt, node = first_online_node;
+ struct irq_desc *desc;
+
+ init_irq_default_affinity();
+
+ /* Let arch update nr_irqs and return the nr of preallocated irqs */
+ initcnt = arch_probe_nr_irqs();
+ printk(KERN_INFO "NR_IRQS:%d nr_irqs:%d %d\n", NR_IRQS, nr_irqs, initcnt);
+
+ if (WARN_ON(nr_irqs > IRQ_BITMAP_BITS))
+ nr_irqs = IRQ_BITMAP_BITS;
+
+ if (WARN_ON(initcnt > IRQ_BITMAP_BITS))
+ initcnt = IRQ_BITMAP_BITS;
+
+ if (initcnt > nr_irqs)
+ nr_irqs = initcnt;
+
+ for (i = 0; i < initcnt; i++) {
+ desc = alloc_desc(i, node);
+ set_bit(i, allocated_irqs);
+ irq_insert_desc(i, desc);
+ }
+ return arch_early_irq_init();
+}
+
+#else /* !CONFIG_SPARSE_IRQ */
+
+struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
+ [0 ... NR_IRQS-1] = {
+ .status = IRQ_DEFAULT_INIT_FLAGS,
+ .handle_irq = handle_bad_irq,
+ .depth = 1,
+ .lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock),
+ }
+};
+
+int __init early_irq_init(void)
+{
+ int count, i, node = first_online_node;
+ struct irq_desc *desc;
+
+ init_irq_default_affinity();
+
+ printk(KERN_INFO "NR_IRQS:%d\n", NR_IRQS);
+
+ desc = irq_desc;
+ count = ARRAY_SIZE(irq_desc);
+
+ for (i = 0; i < count; i++) {
+ desc[i].irq_data.irq = i;
+ desc[i].irq_data.chip = &no_irq_chip;
+ /* TODO : do this allocation on-demand ... */
+ desc[i].kstat_irqs = alloc_percpu(unsigned int);
+ alloc_masks(desc + i, GFP_KERNEL, node);
+ desc_smp_init(desc + i, node);
+ lockdep_set_class(&desc[i].lock, &irq_desc_lock_class);
+ }
+ return arch_early_irq_init();
+}
+
+struct irq_desc *irq_to_desc(unsigned int irq)
+{
+ return (irq < NR_IRQS) ? irq_desc + irq : NULL;
+}
+
+struct irq_desc *irq_to_desc_alloc_node(unsigned int irq, int node)
+{
+ return irq_to_desc(irq);
+}
+
+static void free_desc(unsigned int irq)
+{
+ dynamic_irq_cleanup(irq);
+}
+
+static inline int alloc_descs(unsigned int start, unsigned int cnt, int node)
+{
+#if defined(CONFIG_KSTAT_IRQS_ONDEMAND)
+ struct irq_desc *desc;
+ unsigned int i;
+
+ for (i = 0; i < cnt; i++) {
+ desc = irq_to_desc(start + i);
+ if (desc && !desc->kstat_irqs) {
+ unsigned int __percpu *stats = alloc_percpu(unsigned int);
+
+ if (!stats)
+ return -1;
+ if (cmpxchg(&desc->kstat_irqs, NULL, stats) != NULL)
+ free_percpu(stats);
+ }
+ }
+#endif
+ return start;
+}
+#endif /* !CONFIG_SPARSE_IRQ */
+
+/* Dynamic interrupt handling */
+
+/**
+ * irq_free_descs - free irq descriptors
+ * @from: Start of descriptor range
+ * @cnt: Number of consecutive irqs to free
+ */
+void irq_free_descs(unsigned int from, unsigned int cnt)
+{
+ int i;
+
+ if (from >= nr_irqs || (from + cnt) > nr_irqs)
+ return;
+
+ for (i = 0; i < cnt; i++)
+ free_desc(from + i);
+
+ mutex_lock(&sparse_irq_lock);
+ bitmap_clear(allocated_irqs, from, cnt);
+ mutex_unlock(&sparse_irq_lock);
+}
+
+/**
+ * irq_alloc_descs - allocate and initialize a range of irq descriptors
+ * @irq: Allocate for specific irq number if irq >= 0
+ * @from: Start the search from this irq number
+ * @cnt: Number of consecutive irqs to allocate.
+ * @node: Preferred node on which the irq descriptor should be allocated
+ *
+ * Returns the first irq number or error code
+ */
+int __ref
+irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node)
+{
+ int start, ret;
+
+ if (!cnt)
+ return -EINVAL;
+
+ mutex_lock(&sparse_irq_lock);
+
+ start = bitmap_find_next_zero_area(allocated_irqs, nr_irqs, from, cnt, 0);
+ ret = -EEXIST;
+ if (irq >=0 && start != irq)
+ goto err;
+
+ ret = -ENOMEM;
+ if (start >= nr_irqs)
+ goto err;
+
+ bitmap_set(allocated_irqs, start, cnt);
+ mutex_unlock(&sparse_irq_lock);
+ return alloc_descs(start, cnt, node);
+
+err:
+ mutex_unlock(&sparse_irq_lock);
+ return ret;
+}
+
+/**
+ * irq_reserve_irqs - mark irqs allocated
+ * @from: mark from irq number
+ * @cnt: number of irqs to mark
+ *
+ * Returns 0 on success or an appropriate error code
+ */
+int irq_reserve_irqs(unsigned int from, unsigned int cnt)
+{
+ unsigned int start;
+ int ret = 0;
+
+ if (!cnt || (from + cnt) > nr_irqs)
+ return -EINVAL;
+
+ mutex_lock(&sparse_irq_lock);
+ start = bitmap_find_next_zero_area(allocated_irqs, nr_irqs, from, cnt, 0);
+ if (start == from)
+ bitmap_set(allocated_irqs, start, cnt);
+ else
+ ret = -EEXIST;
+ mutex_unlock(&sparse_irq_lock);
+ return ret;
+}
+
+/**
+ * irq_get_next_irq - get next allocated irq number
+ * @offset: where to start the search
+ *
+ * Returns next irq number after offset or nr_irqs if none is found.
+ */
+unsigned int irq_get_next_irq(unsigned int offset)
+{
+ return find_next_bit(allocated_irqs, nr_irqs, offset);
+}
+
+/**
+ * dynamic_irq_cleanup - cleanup a dynamically allocated irq
+ * @irq: irq number to initialize
+ */
+void dynamic_irq_cleanup(unsigned int irq)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&desc->lock, flags);
+ desc_set_defaults(irq, desc, desc_node(desc));
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+}
+
+unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+
+ return desc && desc->kstat_irqs ?
+ *per_cpu_ptr(desc->kstat_irqs, cpu) : 0;
+}
+
+#ifdef CONFIG_GENERIC_HARDIRQS
+unsigned int kstat_irqs(unsigned int irq)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+ int cpu;
+ int sum = 0;
+
+ if (!desc || !desc->kstat_irqs)
+ return 0;
+ for_each_possible_cpu(cpu)
+ sum += *per_cpu_ptr(desc->kstat_irqs, cpu);
+ return sum;
+}
+#endif /* CONFIG_GENERIC_HARDIRQS */
projects / mv-sheeva.git / blobdiff