3 files changed, 407 insertions, 16 deletions

diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig
index 225086b2652e..4f2eb2b1f23b 100644
--- a/kernel/irq/Kconfig
+++ b/kernel/irq/Kconfig
@@ -55,6 +55,11 @@ config GENERIC_IRQ_CHIP
 config IRQ_DOMAIN
         bool
 
+# Support for hierarchical irq domains
+config IRQ_DOMAIN_HIERARCHY
+        bool
+        select IRQ_DOMAIN
+
 config HANDLE_DOMAIN_IRQ
         bool
 
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index e5202f00cabc..72a93086216b 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -15,6 +15,7 @@
 #include <linux/module.h>
 #include <linux/interrupt.h>
 #include <linux/kernel_stat.h>
+#include <linux/irqdomain.h>
 
 #include <trace/events/irq.h>
 
@@ -178,6 +179,7 @@ int irq_startup(struct irq_desc *desc, bool resend)
         irq_state_clr_disabled(desc);
         desc->depth = 0;
 
+        irq_domain_activate_irq(&desc->irq_data);
         if (desc->irq_data.chip->irq_startup) {
                 ret = desc->irq_data.chip->irq_startup(&desc->irq_data);
                 irq_state_clr_masked(desc);
@@ -199,6 +201,7 @@ void irq_shutdown(struct irq_desc *desc)
                 desc->irq_data.chip->irq_disable(&desc->irq_data);
         else
                 desc->irq_data.chip->irq_mask(&desc->irq_data);
+        irq_domain_deactivate_irq(&desc->irq_data);
         irq_state_set_masked(desc);
 }
 
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 6534ff6ce02e..43f3be6fac70 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -23,6 +23,10 @@ static DEFINE_MUTEX(irq_domain_mutex);
 static DEFINE_MUTEX(revmap_trees_mutex);
 static struct irq_domain *irq_default_domain;
 
+static int irq_domain_alloc_descs(int virq, unsigned int nr_irqs,
+                                  irq_hw_number_t hwirq, int node);
+static void irq_domain_check_hierarchy(struct irq_domain *domain);
+
 /**
  * __irq_domain_add() - Allocate a new irq_domain data structure
  * @of_node: optional device-tree node of the interrupt controller
@@ -30,7 +34,7 @@ static struct irq_domain *irq_default_domain;
  * @hwirq_max: Maximum number of interrupts supported by controller
  * @direct_max: Maximum value of direct maps; Use ~0 for no limit; 0 for no
  *              direct mapping
- * @ops: map/unmap domain callbacks
+ * @ops: domain callbacks
  * @host_data: Controller private data pointer
  *
  * Allocates and initialize and irq_domain structure.
@@ -56,6 +60,7 @@ struct irq_domain *__irq_domain_add(struct device_node *of_node, int size,
         domain->hwirq_max = hwirq_max;
         domain->revmap_size = size;
         domain->revmap_direct_max_irq = direct_max;
+        irq_domain_check_hierarchy(domain);
 
         mutex_lock(&irq_domain_mutex);
         list_add(&domain->link, &irq_domain_list);
@@ -109,7 +114,7 @@ EXPORT_SYMBOL_GPL(irq_domain_remove);
  * @first_irq: first number of irq block assigned to the domain,
  *      pass zero to assign irqs on-the-fly. If first_irq is non-zero, then
  *      pre-map all of the irqs in the domain to virqs starting at first_irq.
- * @ops: map/unmap domain callbacks
+ * @ops: domain callbacks
  * @host_data: Controller private data pointer
  *
  * Allocates an irq_domain, and optionally if first_irq is positive then also
@@ -174,10 +179,8 @@ struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
 
         domain = __irq_domain_add(of_node, first_hwirq + size,
                                   first_hwirq + size, 0, ops, host_data);
-        if (!domain)
-                return NULL;
-
-        irq_domain_associate_many(domain, first_irq, first_hwirq, size);
+        if (domain)
+                irq_domain_associate_many(domain, first_irq, first_hwirq, size);
 
         return domain;
 }
@@ -388,7 +391,6 @@ EXPORT_SYMBOL_GPL(irq_create_direct_mapping);
 unsigned int irq_create_mapping(struct irq_domain *domain,
                                 irq_hw_number_t hwirq)
 {
-        unsigned int hint;
         int virq;
 
         pr_debug("irq_create_mapping(0x%p, 0x%lx)\n", domain, hwirq);
@@ -410,12 +412,8 @@ unsigned int irq_create_mapping(struct irq_domain *domain,
         }
 
         /* Allocate a virtual interrupt number */
-        hint = hwirq % nr_irqs;
-        if (hint == 0)
-                hint++;
-        virq = irq_alloc_desc_from(hint, of_node_to_nid(domain->of_node));
-        if (virq <= 0)
-                virq = irq_alloc_desc_from(1, of_node_to_nid(domain->of_node));
+        virq = irq_domain_alloc_descs(-1, 1, hwirq,
+                                      of_node_to_nid(domain->of_node));
         if (virq <= 0) {
                 pr_debug("-> virq allocation failed\n");
                 return 0;
@@ -471,7 +469,7 @@ unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data)
         struct irq_domain *domain;
         irq_hw_number_t hwirq;
         unsigned int type = IRQ_TYPE_NONE;
-        unsigned int virq;
+        int virq;
 
         domain = irq_data->np ? irq_find_host(irq_data->np) : irq_default_domain;
         if (!domain) {
@@ -480,6 +478,11 @@ unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data)
                 return 0;
         }
 
+        if (irq_domain_is_hierarchy(domain)) {
+                virq = irq_domain_alloc_irqs(domain, 1, NUMA_NO_NODE, irq_data);
+                return virq <= 0 ? 0 : virq;
+        }
+
         /* If domain has no translation, then we assume interrupt line */
         if (domain->ops->xlate == NULL)
                 hwirq = irq_data->args[0];
@@ -540,8 +543,8 @@ unsigned int irq_find_mapping(struct irq_domain *domain,
                 return 0;
 
         if (hwirq < domain->revmap_direct_max_irq) {
-                data = irq_get_irq_data(hwirq);
-                if (data && (data->domain == domain) && (data->hwirq == hwirq))
+                data = irq_domain_get_irq_data(domain, hwirq);
+                if (data && data->hwirq == hwirq)
                         return hwirq;
         }
 
@@ -709,3 +712,383 @@ const struct irq_domain_ops irq_domain_simple_ops = {
         .xlate = irq_domain_xlate_onetwocell,
 };
 EXPORT_SYMBOL_GPL(irq_domain_simple_ops);
+
+static int irq_domain_alloc_descs(int virq, unsigned int cnt,
+                                  irq_hw_number_t hwirq, int node)
+{
+        unsigned int hint;
+
+        if (virq >= 0) {
+                virq = irq_alloc_descs(virq, virq, cnt, node);
+        } else {
+                hint = hwirq % nr_irqs;
+                if (hint == 0)
+                        hint++;
+                virq = irq_alloc_descs_from(hint, cnt, node);
+                if (virq <= 0 && hint > 1)
+                        virq = irq_alloc_descs_from(1, cnt, node);
+        }
+
+        return virq;
+}
+
+#ifdef  CONFIG_IRQ_DOMAIN_HIERARCHY
+static void irq_domain_insert_irq(int virq)
+{
+        struct irq_data *data;
+
+        for (data = irq_get_irq_data(virq); data; data = data->parent_data) {
+                struct irq_domain *domain = data->domain;
+                irq_hw_number_t hwirq = data->hwirq;
+
+                if (hwirq < domain->revmap_size) {
+                        domain->linear_revmap[hwirq] = virq;
+                } else {
+                        mutex_lock(&revmap_trees_mutex);
+                        radix_tree_insert(&domain->revmap_tree, hwirq, data);
+                        mutex_unlock(&revmap_trees_mutex);
+                }
+
+                /* If not already assigned, give the domain the chip's name */
+                if (!domain->name && data->chip)
+                        domain->name = data->chip->name;
+        }
+
+        irq_clear_status_flags(virq, IRQ_NOREQUEST);
+}
+
+static void irq_domain_remove_irq(int virq)
+{
+        struct irq_data *data;
+
+        irq_set_status_flags(virq, IRQ_NOREQUEST);
+        irq_set_chip_and_handler(virq, NULL, NULL);
+        synchronize_irq(virq);
+        smp_mb();
+
+        for (data = irq_get_irq_data(virq); data; data = data->parent_data) {
+                struct irq_domain *domain = data->domain;
+                irq_hw_number_t hwirq = data->hwirq;
+
+                if (hwirq < domain->revmap_size) {
+                        domain->linear_revmap[hwirq] = 0;
+                } else {
+                        mutex_lock(&revmap_trees_mutex);
+                        radix_tree_delete(&domain->revmap_tree, hwirq);
+                        mutex_unlock(&revmap_trees_mutex);
+                }
+        }
+}
+
+static struct irq_data *irq_domain_insert_irq_data(struct irq_domain *domain,
+                                                   struct irq_data *child)
+{
+        struct irq_data *irq_data;
+
+        irq_data = kzalloc_node(sizeof(*irq_data), GFP_KERNEL, child->node);
+        if (irq_data) {
+                child->parent_data = irq_data;
+                irq_data->irq = child->irq;
+                irq_data->node = child->node;
+                irq_data->domain = domain;
+        }
+
+        return irq_data;
+}
+
+static void irq_domain_free_irq_data(unsigned int virq, unsigned int nr_irqs)
+{
+        struct irq_data *irq_data, *tmp;
+        int i;
+
+        for (i = 0; i < nr_irqs; i++) {
+                irq_data = irq_get_irq_data(virq + i);
+                tmp = irq_data->parent_data;
+                irq_data->parent_data = NULL;
+                irq_data->domain = NULL;
+
+                while (tmp) {
+                        irq_data = tmp;
+                        tmp = tmp->parent_data;
+                        kfree(irq_data);
+                }
+        }
+}
+
+static int irq_domain_alloc_irq_data(struct irq_domain *domain,
+                                     unsigned int virq, unsigned int nr_irqs)
+{
+        struct irq_data *irq_data;
+        struct irq_domain *parent;
+        int i;
+
+        /* The outermost irq_data is embedded in struct irq_desc */
+        for (i = 0; i < nr_irqs; i++) {
+                irq_data = irq_get_irq_data(virq + i);
+                irq_data->domain = domain;
+
+                for (parent = domain->parent; parent; parent = parent->parent) {
+                        irq_data = irq_domain_insert_irq_data(parent, irq_data);
+                        if (!irq_data) {
+                                irq_domain_free_irq_data(virq, i + 1);
+                                return -ENOMEM;
+                        }
+                }
+        }
+
+        return 0;
+}
+
+/**
+ * irq_domain_get_irq_data - Get irq_data associated with @virq and @domain
+ * @domain:     domain to match
+ * @virq:       IRQ number to get irq_data
+ */
+struct irq_data *irq_domain_get_irq_data(struct irq_domain *domain,
+                                         unsigned int virq)
+{
+        struct irq_data *irq_data;
+
+        for (irq_data = irq_get_irq_data(virq); irq_data;
+             irq_data = irq_data->parent_data)
+                if (irq_data->domain == domain)
+                        return irq_data;
+
+        return NULL;
+}
+
+/**
+ * irq_domain_set_hwirq_and_chip - Set hwirq and irqchip of @virq at @domain
+ * @domain:     Interrupt domain to match
+ * @virq:       IRQ number
+ * @hwirq:      The hwirq number
+ * @chip:       The associated interrupt chip
+ * @chip_data:  The associated chip data
+ */
+int irq_domain_set_hwirq_and_chip(struct irq_domain *domain, unsigned int virq,
+                                  irq_hw_number_t hwirq, struct irq_chip *chip,
+                                  void *chip_data)
+{
+        struct irq_data *irq_data = irq_domain_get_irq_data(domain, virq);
+
+        if (!irq_data)
+                return -ENOENT;
+
+        irq_data->hwirq = hwirq;
+        irq_data->chip = chip ? chip : &no_irq_chip;
+        irq_data->chip_data = chip_data;
+
+        return 0;
+}
+
+/**
+ * irq_domain_reset_irq_data - Clear hwirq, chip and chip_data in @irq_data
+ * @irq_data:   The pointer to irq_data
+ */
+void irq_domain_reset_irq_data(struct irq_data *irq_data)
+{
+        irq_data->hwirq = 0;
+        irq_data->chip = &no_irq_chip;
+        irq_data->chip_data = NULL;
+}
+
+/**
+ * irq_domain_free_irqs_common - Clear irq_data and free the parent
+ * @domain:     Interrupt domain to match
+ * @virq:       IRQ number to start with
+ * @nr_irqs:    The number of irqs to free
+ */
+void irq_domain_free_irqs_common(struct irq_domain *domain, unsigned int virq,
+                                 unsigned int nr_irqs)
+{
+        struct irq_data *irq_data;
+        int i;
+
+        for (i = 0; i < nr_irqs; i++) {
+                irq_data = irq_domain_get_irq_data(domain, virq + i);
+                if (irq_data)
+                        irq_domain_reset_irq_data(irq_data);
+        }
+        irq_domain_free_irqs_parent(domain, virq, nr_irqs);
+}
+
+/**
+ * irq_domain_free_irqs_top - Clear handler and handler data, clear irqdata and free parent
+ * @domain:     Interrupt domain to match
+ * @virq:       IRQ number to start with
+ * @nr_irqs:    The number of irqs to free
+ */
+void irq_domain_free_irqs_top(struct irq_domain *domain, unsigned int virq,
+                              unsigned int nr_irqs)
+{
+        int i;
+
+        for (i = 0; i < nr_irqs; i++) {
+                irq_set_handler_data(virq + i, NULL);
+                irq_set_handler(virq + i, NULL);
+        }
+        irq_domain_free_irqs_common(domain, virq, nr_irqs);
+}
+
+/**
+ * __irq_domain_alloc_irqs - Allocate IRQs from domain
+ * @domain:     domain to allocate from
+ * @irq_base:   allocate specified IRQ nubmer if irq_base >= 0
+ * @nr_irqs:    number of IRQs to allocate
+ * @node:       NUMA node id for memory allocation
+ * @arg:        domain specific argument
+ * @realloc:    IRQ descriptors have already been allocated if true
+ *
+ * Allocate IRQ numbers and initialized all data structures to support
+ * hierarchy IRQ domains.
+ * Parameter @realloc is mainly to support legacy IRQs.
+ * Returns error code or allocated IRQ number
+ *
+ * The whole process to setup an IRQ has been split into two steps.
+ * The first step, __irq_domain_alloc_irqs(), is to allocate IRQ
+ * descriptor and required hardware resources. The second step,
+ * irq_domain_activate_irq(), is to program hardwares with preallocated
+ * resources. In this way, it's easier to rollback when failing to
+ * allocate resources.
+ */
+int __irq_domain_alloc_irqs(struct irq_domain *domain, int irq_base,
+                            unsigned int nr_irqs, int node, void *arg,
+                            bool realloc)
+{
+        int i, ret, virq;
+
+        if (domain == NULL) {
+                domain = irq_default_domain;
+                if (WARN(!domain, "domain is NULL; cannot allocate IRQ\n"))
+                        return -EINVAL;
+        }
+
+        if (!domain->ops->alloc) {
+                pr_debug("domain->ops->alloc() is NULL\n");
+                return -ENOSYS;
+        }
+
+        if (realloc && irq_base >= 0) {
+                virq = irq_base;
+        } else {
+                virq = irq_domain_alloc_descs(irq_base, nr_irqs, 0, node);
+                if (virq < 0) {
+                        pr_debug("cannot allocate IRQ(base %d, count %d)\n",
+                                 irq_base, nr_irqs);
+                        return virq;
+                }
+        }
+
+        if (irq_domain_alloc_irq_data(domain, virq, nr_irqs)) {
+                pr_debug("cannot allocate memory for IRQ%d\n", virq);
+                ret = -ENOMEM;
+                goto out_free_desc;
+        }
+
+        mutex_lock(&irq_domain_mutex);
+        ret = domain->ops->alloc(domain, virq, nr_irqs, arg);
+        if (ret < 0) {
+                mutex_unlock(&irq_domain_mutex);
+                goto out_free_irq_data;
+        }
+        for (i = 0; i < nr_irqs; i++)
+                irq_domain_insert_irq(virq + i);
+        mutex_unlock(&irq_domain_mutex);
+
+        return virq;
+
+out_free_irq_data:
+        irq_domain_free_irq_data(virq, nr_irqs);
+out_free_desc:
+        irq_free_descs(virq, nr_irqs);
+        return ret;
+}
+
+/**
+ * irq_domain_free_irqs - Free IRQ number and associated data structures
+ * @virq:       base IRQ number
+ * @nr_irqs:    number of IRQs to free
+ */
+void irq_domain_free_irqs(unsigned int virq, unsigned int nr_irqs)
+{
+        struct irq_data *data = irq_get_irq_data(virq);
+        int i;
+
+        if (WARN(!data || !data->domain || !data->domain->ops->free,
+                 "NULL pointer, cannot free irq\n"))
+                return;
+
+        mutex_lock(&irq_domain_mutex);
+        for (i = 0; i < nr_irqs; i++)
+                irq_domain_remove_irq(virq + i);
+        data->domain->ops->free(data->domain, virq, nr_irqs);
+        mutex_unlock(&irq_domain_mutex);
+
+        irq_domain_free_irq_data(virq, nr_irqs);
+        irq_free_descs(virq, nr_irqs);
+}
+
+/**
+ * irq_domain_activate_irq - Call domain_ops->activate recursively to activate
+ *                           interrupt
+ * @irq_data:   outermost irq_data associated with interrupt
+ *
+ * This is the second step to call domain_ops->activate to program interrupt
+ * controllers, so the interrupt could actually get delivered.
+ */
+void irq_domain_activate_irq(struct irq_data *irq_data)
+{
+        if (irq_data && irq_data->domain) {
+                struct irq_domain *domain = irq_data->domain;
+
+                if (irq_data->parent_data)
+                        irq_domain_activate_irq(irq_data->parent_data);
+                if (domain->ops->activate)
+                        domain->ops->activate(domain, irq_data);
+        }
+}
+
+/**
+ * irq_domain_deactivate_irq - Call domain_ops->deactivate recursively to
+ *                             deactivate interrupt
+ * @irq_data: outermost irq_data associated with interrupt
+ *
+ * It calls domain_ops->deactivate to program interrupt controllers to disable
+ * interrupt delivery.
+ */
+void irq_domain_deactivate_irq(struct irq_data *irq_data)
+{
+        if (irq_data && irq_data->domain) {
+                struct irq_domain *domain = irq_data->domain;
+
+                if (domain->ops->deactivate)
+                        domain->ops->deactivate(domain, irq_data);
+                if (irq_data->parent_data)
+                        irq_domain_deactivate_irq(irq_data->parent_data);
+        }
+}
+
+static void irq_domain_check_hierarchy(struct irq_domain *domain)
+{
+        /* Hierarchy irq_domains must implement callback alloc() */
+        if (domain->ops->alloc)
+                domain->flags |= IRQ_DOMAIN_FLAG_HIERARCHY;
+}
+#else   /* CONFIG_IRQ_DOMAIN_HIERARCHY */
+/**
+ * irq_domain_get_irq_data - Get irq_data associated with @virq and @domain
+ * @domain:     domain to match
+ * @virq:       IRQ number to get irq_data
+ */
+struct irq_data *irq_domain_get_irq_data(struct irq_domain *domain,
+                                         unsigned int virq)
+{
+        struct irq_data *irq_data = irq_get_irq_data(virq);
+
+        return (irq_data && irq_data->domain == domain) ? irq_data : NULL;
+}
+
+static void irq_domain_check_hierarchy(struct irq_domain *domain)
+{
+}
+#endif  /* CONFIG_IRQ_DOMAIN_HIERARCHY */