Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq updates from Thomas Gleixner:
 "The irq department provides:

   - Support for MSI to wire bridges and a first user of it

   - More ACPI support for ARM/GIC

   - A new TS-4800 interrupt controller driver

   - RCU based free of interrupt descriptors to support the upcoming
     Intel VMD technology without introducing a locking nightmare

   - The usual pile of fixes and updates to drivers and core code"

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (41 commits)
  irqchip/omap-intc: Add support for spurious irq handling
  irqchip/zevio: Use irq_data_get_chip_type() helper
  irqchip/omap-intc: Remove duplicate setup for IRQ chip type handler
  irqchip/ts4800: Add TS-4800 interrupt controller
  irqchip/ts4800: Add documentation for TS-4800 interrupt controller
  irq/platform-MSI: Increase the maximum MSIs the MSI framework can support
  irqchip/gicv2m: Miscellaneous fixes for v2m resources and SPI ranges
  irqchip/bcm2836: Make code more readable
  irqchip/bcm2836: Tolerate IRQs while no flag is set in ISR
  irqchip/bcm2836: Add SMP support for the 2836
  irqchip/bcm2836: Fix initialization of the LOCAL_IRQ_CNT timers
  irqchip/gic-v2m: acpi: Introducing GICv2m ACPI support
  irqchip/gic-v2m: Refactor to prepare for ACPI support
  irqdomain: Introduce is_fwnode_irqchip helper
  acpi: pci: Setup MSI domain for ACPI based pci devices
  genirq/msi: Export functions to allow MSI domains in modules
  irqchip/mbigen: Implement the mbigen irq chip operation functions
  irqchip/mbigen: Create irq domain for each mbigen device
  irqchip/mgigen: Add platform device driver for mbigen device
  dt-bindings: Documents the mbigen bindings
  ...

kernel/irq/chip.c

@@ -338,7 +338,6 @@ void handle_nested_irq(unsigned int irq)
 	raw_spin_lock_irq(&desc->lock);
 
 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
-	kstat_incr_irqs_this_cpu(desc);
 
 	action = desc->action;
 	if (unlikely(!action || irqd_irq_disabled(&desc->irq_data))) {
@@ -346,6 +345,7 @@ void handle_nested_irq(unsigned int irq)
 		goto out_unlock;
 	}
 
+	kstat_incr_irqs_this_cpu(desc);
 	irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS);
 	raw_spin_unlock_irq(&desc->lock);
 
@@ -412,13 +412,13 @@ void handle_simple_irq(struct irq_desc *desc)
 		goto out_unlock;
 
 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
-	kstat_incr_irqs_this_cpu(desc);
 
 	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
 		desc->istate |= IRQS_PENDING;
 		goto out_unlock;
 	}
 
+	kstat_incr_irqs_this_cpu(desc);
 	handle_irq_event(desc);
 
 out_unlock:
@@ -462,7 +462,6 @@ void handle_level_irq(struct irq_desc *desc)
 		goto out_unlock;
 
 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
-	kstat_incr_irqs_this_cpu(desc);
 
 	/*
 	 * If its disabled or no action available
@@ -473,6 +472,7 @@ void handle_level_irq(struct irq_desc *desc)
 		goto out_unlock;
 	}
 
+	kstat_incr_irqs_this_cpu(desc);
 	handle_irq_event(desc);
 
 	cond_unmask_irq(desc);
@@ -532,7 +532,6 @@ void handle_fasteoi_irq(struct irq_desc *desc)
 		goto out;
 
 	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
-	kstat_incr_irqs_this_cpu(desc);
 
 	/*
 	 * If its disabled or no action available
@@ -544,6 +543,7 @@ void handle_fasteoi_irq(struct irq_desc *desc)
 		goto out;
 	}
 
+	kstat_incr_irqs_this_cpu(desc);
 	if (desc->istate & IRQS_ONESHOT)
 		mask_irq(desc);
 
@@ -950,6 +950,7 @@ void irq_chip_ack_parent(struct irq_data *data)
 	data = data->parent_data;
 	data->chip->irq_ack(data);
 }
+EXPORT_SYMBOL_GPL(irq_chip_ack_parent);
 
 /**
  * irq_chip_mask_parent - Mask the parent interrupt

kernel/irq/irqdesc.c

@@ -159,6 +159,7 @@ static struct irq_desc *alloc_desc(int irq, int node, struct module *owner)
 
 	raw_spin_lock_init(&desc->lock);
 	lockdep_set_class(&desc->lock, &irq_desc_lock_class);
+	init_rcu_head(&desc->rcu);
 
 	desc_set_defaults(irq, desc, node, owner);
 
@@ -171,6 +172,15 @@ err_desc:
 	return NULL;
 }
 
+static void delayed_free_desc(struct rcu_head *rhp)
+{
+	struct irq_desc *desc = container_of(rhp, struct irq_desc, rcu);
+
+	free_masks(desc);
+	free_percpu(desc->kstat_irqs);
+	kfree(desc);
+}
+
 static void free_desc(unsigned int irq)
 {
 	struct irq_desc *desc = irq_to_desc(irq);
@@ -187,9 +197,12 @@ static void free_desc(unsigned int irq)
 	delete_irq_desc(irq);
 	mutex_unlock(&sparse_irq_lock);
 
-	free_masks(desc);
-	free_percpu(desc->kstat_irqs);
-	kfree(desc);
+	/*
+	 * We free the descriptor, masks and stat fields via RCU. That
+	 * allows demultiplex interrupts to do rcu based management of
+	 * the child interrupts.
+	 */
+	call_rcu(&desc->rcu, delayed_free_desc);
 }
 
 static int alloc_descs(unsigned int start, unsigned int cnt, int node,

kernel/irq/irqdomain.c

@@ -60,6 +60,7 @@ struct fwnode_handle *irq_domain_alloc_fwnode(void *data)
 	fwid->fwnode.type = FWNODE_IRQCHIP;
 	return &fwid->fwnode;
 }
+EXPORT_SYMBOL_GPL(irq_domain_alloc_fwnode);
 
 /**
  * irq_domain_free_fwnode - Free a non-OF-backed fwnode_handle
@@ -70,13 +71,14 @@ void irq_domain_free_fwnode(struct fwnode_handle *fwnode)
 {
 	struct irqchip_fwid *fwid;
 
-	if (WARN_ON(fwnode->type != FWNODE_IRQCHIP))
+	if (WARN_ON(!is_fwnode_irqchip(fwnode)))
 		return;
 
 	fwid = container_of(fwnode, struct irqchip_fwid, fwnode);
 	kfree(fwid->name);
 	kfree(fwid);
 }
+EXPORT_SYMBOL_GPL(irq_domain_free_fwnode);
 
 /**
  * __irq_domain_add() - Allocate a new irq_domain data structure
@@ -1013,6 +1015,7 @@ struct irq_data *irq_domain_get_irq_data(struct irq_domain *domain,
 
 	return NULL;
 }
+EXPORT_SYMBOL_GPL(irq_domain_get_irq_data);
 
 /**
  * irq_domain_set_hwirq_and_chip - Set hwirq and irqchip of @virq at @domain
@@ -1125,9 +1128,9 @@ static void irq_domain_free_irqs_recursive(struct irq_domain *domain,
 	}
 }
 
-static int irq_domain_alloc_irqs_recursive(struct irq_domain *domain,
-					   unsigned int irq_base,
-					   unsigned int nr_irqs, void *arg)
+int irq_domain_alloc_irqs_recursive(struct irq_domain *domain,
+				    unsigned int irq_base,
+				    unsigned int nr_irqs, void *arg)
 {
 	int ret = 0;
 	struct irq_domain *parent = domain->parent;
@@ -1343,6 +1346,7 @@ struct irq_data *irq_domain_get_irq_data(struct irq_domain *domain,
 
 	return (irq_data && irq_data->domain == domain) ? irq_data : NULL;
 }
+EXPORT_SYMBOL_GPL(irq_domain_get_irq_data);
 
 /**
  * irq_domain_set_info - Set the complete data for a @virq in @domain

kernel/irq/manage.c

@@ -1743,6 +1743,31 @@ out:
 }
 EXPORT_SYMBOL_GPL(enable_percpu_irq);
 
+/**
+ * irq_percpu_is_enabled - Check whether the per cpu irq is enabled
+ * @irq:	Linux irq number to check for
+ *
+ * Must be called from a non migratable context. Returns the enable
+ * state of a per cpu interrupt on the current cpu.
+ */
+bool irq_percpu_is_enabled(unsigned int irq)
+{
+	unsigned int cpu = smp_processor_id();
+	struct irq_desc *desc;
+	unsigned long flags;
+	bool is_enabled;
+
+	desc = irq_get_desc_lock(irq, &flags, IRQ_GET_DESC_CHECK_PERCPU);
+	if (!desc)
+		return false;
+
+	is_enabled = cpumask_test_cpu(cpu, desc->percpu_enabled);
+	irq_put_desc_unlock(desc, flags);
+
+	return is_enabled;
+}
+EXPORT_SYMBOL_GPL(irq_percpu_is_enabled);
+
 void disable_percpu_irq(unsigned int irq)
 {
 	unsigned int cpu = smp_processor_id();

kernel/irq/msi.c

@@ -252,6 +252,60 @@ struct irq_domain *msi_create_irq_domain(struct fwnode_handle *fwnode,
 					   &msi_domain_ops, info);
 }
 
+int msi_domain_prepare_irqs(struct irq_domain *domain, struct device *dev,
+			    int nvec, msi_alloc_info_t *arg)
+{
+	struct msi_domain_info *info = domain->host_data;
+	struct msi_domain_ops *ops = info->ops;
+	int ret;
+
+	ret = ops->msi_check(domain, info, dev);
+	if (ret == 0)
+		ret = ops->msi_prepare(domain, dev, nvec, arg);
+
+	return ret;
+}
+
+int msi_domain_populate_irqs(struct irq_domain *domain, struct device *dev,
+			     int virq, int nvec, msi_alloc_info_t *arg)
+{
+	struct msi_domain_info *info = domain->host_data;
+	struct msi_domain_ops *ops = info->ops;
+	struct msi_desc *desc;
+	int ret = 0;
+
+	for_each_msi_entry(desc, dev) {
+		/* Don't even try the multi-MSI brain damage. */
+		if (WARN_ON(!desc->irq || desc->nvec_used != 1)) {
+			ret = -EINVAL;
+			break;
+		}
+
+		if (!(desc->irq >= virq && desc->irq < (virq + nvec)))
+			continue;
+
+		ops->set_desc(arg, desc);
+		/* Assumes the domain mutex is held! */
+		ret = irq_domain_alloc_irqs_recursive(domain, virq, 1, arg);
+		if (ret)
+			break;
+
+		irq_set_msi_desc_off(virq, 0, desc);
+	}
+
+	if (ret) {
+		/* Mop up the damage */
+		for_each_msi_entry(desc, dev) {
+			if (!(desc->irq >= virq && desc->irq < (virq + nvec)))
+				continue;
+
+			irq_domain_free_irqs_common(domain, desc->irq, 1);
+		}
+	}
+
+	return ret;
+}
+
 /**
  * msi_domain_alloc_irqs - Allocate interrupts from a MSI interrupt domain
  * @domain:	The domain to allocate from
@@ -270,9 +324,7 @@ int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,
 	struct msi_desc *desc;
 	int i, ret, virq = -1;
 
-	ret = ops->msi_check(domain, info, dev);
-	if (ret == 0)
-		ret = ops->msi_prepare(domain, dev, nvec, &arg);
+	ret = msi_domain_prepare_irqs(domain, dev, nvec, &arg);
 	if (ret)
 		return ret;