genirq: Generic chip: Add linear irq domain support
Provide infrastructure for irq chip implementations which work on
linear irq domains.
- Interface to allocate multiple generic chips which are associated to
the irq domain.
- Interface to get the generic chip pointer for a particular hardware
interrupt in the domain.
- irq domain mapping function to install the chip for a particular
interrupt.
Note: This lacks a removal function for now.
[ Sebastian Hesselbarth: Mask cache and pointer math fixups ]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jean-Francois Moine <moinejf@free.fr>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Cc: Gregory Clement <gregory.clement@free-electrons.com>
Cc: Gerlando Falauto <gerlando.falauto@keymile.com>
Cc: Rob Landley <rob@landley.net>
Acked-by: Grant Likely <grant.likely@linaro.org>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Link: http://lkml.kernel.org/r/20130506142539.450634298@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/kernel/irq/generic-chip.c b/kernel/irq/generic-chip.c
index 3deb333..8743d62 100644
--- a/kernel/irq/generic-chip.c
+++ b/kernel/irq/generic-chip.c
@@ -7,6 +7,7 @@
#include <linux/irq.h>
#include <linux/slab.h>
#include <linux/export.h>
+#include <linux/irqdomain.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/syscore_ops.h>
@@ -244,6 +245,90 @@
}
}
+/**
+ * irq_alloc_domain_generic_chip - Allocate generic chips for an irq domain
+ * @d: irq domain for which to allocate chips
+ * @irqs_per_chip: Number of interrupts each chip handles
+ * @num_ct: Number of irq_chip_type instances associated with this
+ * @name: Name of the irq chip
+ * @handler: Default flow handler associated with these chips
+ * @clr: IRQ_* bits to clear in the mapping function
+ * @set: IRQ_* bits to set in the mapping function
+ */
+int irq_alloc_domain_generic_chips(struct irq_domain *d, int irqs_per_chip,
+ int num_ct, const char *name,
+ irq_flow_handler_t handler,
+ unsigned int clr, unsigned int set,
+ enum irq_gc_flags gcflags)
+{
+ struct irq_domain_chip_generic *dgc;
+ struct irq_chip_generic *gc;
+ int numchips, sz, i;
+ unsigned long flags;
+ void *tmp;
+
+ if (d->gc)
+ return -EBUSY;
+
+ if (d->revmap_type != IRQ_DOMAIN_MAP_LINEAR)
+ return -EINVAL;
+
+ numchips = d->revmap_data.linear.size / irqs_per_chip;
+ if (!numchips)
+ return -EINVAL;
+
+ /* Allocate a pointer, generic chip and chiptypes for each chip */
+ sz = sizeof(*dgc) + numchips * sizeof(gc);
+ sz += numchips * (sizeof(*gc) + num_ct * sizeof(struct irq_chip_type));
+
+ tmp = dgc = kzalloc(sz, GFP_KERNEL);
+ if (!dgc)
+ return -ENOMEM;
+ dgc->irqs_per_chip = irqs_per_chip;
+ dgc->num_chips = numchips;
+ dgc->irq_flags_to_set = set;
+ dgc->irq_flags_to_clear = clr;
+ dgc->gc_flags = gcflags;
+ d->gc = dgc;
+
+ /* Calc pointer to the first generic chip */
+ tmp += sizeof(*dgc) + numchips * sizeof(gc);
+ for (i = 0; i < numchips; i++) {
+ /* Store the pointer to the generic chip */
+ dgc->gc[i] = gc = tmp;
+ irq_init_generic_chip(gc, name, num_ct, i * irqs_per_chip,
+ NULL, handler);
+ gc->domain = d;
+ raw_spin_lock_irqsave(&gc_lock, flags);
+ list_add_tail(&gc->list, &gc_list);
+ raw_spin_unlock_irqrestore(&gc_lock, flags);
+ /* Calc pointer to the next generic chip */
+ tmp += sizeof(*gc) + num_ct * sizeof(struct irq_chip_type);
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(irq_alloc_domain_generic_chips);
+
+/**
+ * irq_get_domain_generic_chip - Get a pointer to the generic chip of a hw_irq
+ * @d: irq domain pointer
+ * @hw_irq: Hardware interrupt number
+ */
+struct irq_chip_generic *
+irq_get_domain_generic_chip(struct irq_domain *d, unsigned int hw_irq)
+{
+ struct irq_domain_chip_generic *dgc = d->gc;
+ int idx;
+
+ if (!dgc)
+ return NULL;
+ idx = hw_irq / dgc->irqs_per_chip;
+ if (idx >= dgc->num_chips)
+ return NULL;
+ return dgc->gc[idx];
+}
+EXPORT_SYMBOL_GPL(irq_get_domain_generic_chip);
+
/*
* Separate lockdep class for interrupt chip which can nest irq_desc
* lock.
@@ -251,6 +336,66 @@
static struct lock_class_key irq_nested_lock_class;
/**
+ * irq_map_generic_chip - Map a generic chip for an irq domain
+ */
+static int irq_map_generic_chip(struct irq_domain *d, unsigned int virq,
+ irq_hw_number_t hw_irq)
+{
+ struct irq_data *data = irq_get_irq_data(virq);
+ struct irq_domain_chip_generic *dgc = d->gc;
+ struct irq_chip_generic *gc;
+ struct irq_chip_type *ct;
+ struct irq_chip *chip;
+ unsigned long flags;
+ int idx;
+
+ if (!d->gc)
+ return -ENODEV;
+
+ idx = hw_irq / dgc->irqs_per_chip;
+ if (idx >= dgc->num_chips)
+ return -EINVAL;
+ gc = dgc->gc[idx];
+
+ idx = hw_irq % dgc->irqs_per_chip;
+
+ if (test_bit(idx, &gc->installed))
+ return -EBUSY;
+
+ ct = gc->chip_types;
+ chip = &ct->chip;
+
+ /* We only init the cache for the first mapping of a generic chip */
+ if (!gc->installed) {
+ raw_spin_lock_irqsave(&gc->lock, flags);
+ irq_gc_init_mask_cache(gc, dgc->gc_flags);
+ raw_spin_unlock_irqrestore(&gc->lock, flags);
+ }
+
+ /* Mark the interrupt as installed */
+ set_bit(idx, &gc->installed);
+
+ if (dgc->gc_flags & IRQ_GC_INIT_NESTED_LOCK)
+ irq_set_lockdep_class(virq, &irq_nested_lock_class);
+
+ if (chip->irq_calc_mask)
+ chip->irq_calc_mask(data);
+ else
+ data->mask = 1 << idx;
+
+ irq_set_chip_and_handler(virq, chip, ct->handler);
+ irq_set_chip_data(virq, gc);
+ irq_modify_status(virq, dgc->irq_flags_to_clear, dgc->irq_flags_to_set);
+ return 0;
+}
+
+struct irq_domain_ops irq_generic_chip_ops = {
+ .map = irq_map_generic_chip,
+ .xlate = irq_domain_xlate_onetwocell,
+};
+EXPORT_SYMBOL_GPL(irq_generic_chip_ops);
+
+/**
* irq_setup_generic_chip - Setup a range of interrupts with a generic chip
* @gc: Generic irq chip holding all data
* @msk: Bitmask holding the irqs to initialize relative to gc->irq_base
@@ -354,6 +499,24 @@
}
EXPORT_SYMBOL_GPL(irq_remove_generic_chip);
+static struct irq_data *irq_gc_get_irq_data(struct irq_chip_generic *gc)
+{
+ unsigned int virq;
+
+ if (!gc->domain)
+ return irq_get_irq_data(gc->irq_base);
+
+ /*
+ * We don't know which of the irqs has been actually
+ * installed. Use the first one.
+ */
+ if (!gc->installed)
+ return NULL;
+
+ virq = irq_find_mapping(gc->domain, gc->irq_base + __ffs(gc->installed));
+ return virq ? irq_get_irq_data(virq) : NULL;
+}
+
#ifdef CONFIG_PM
static int irq_gc_suspend(void)
{
@@ -362,8 +525,12 @@
list_for_each_entry(gc, &gc_list, list) {
struct irq_chip_type *ct = gc->chip_types;
- if (ct->chip.irq_suspend)
- ct->chip.irq_suspend(irq_get_irq_data(gc->irq_base));
+ if (ct->chip.irq_suspend) {
+ struct irq_data *data = irq_gc_get_irq_data(gc);
+
+ if (data)
+ ct->chip.irq_suspend(data);
+ }
}
return 0;
}
@@ -375,8 +542,12 @@
list_for_each_entry(gc, &gc_list, list) {
struct irq_chip_type *ct = gc->chip_types;
- if (ct->chip.irq_resume)
- ct->chip.irq_resume(irq_get_irq_data(gc->irq_base));
+ if (ct->chip.irq_resume) {
+ struct irq_data *data = irq_gc_get_irq_data(gc);
+
+ if (data)
+ ct->chip.irq_resume(data);
+ }
}
}
#else
@@ -391,8 +562,12 @@
list_for_each_entry(gc, &gc_list, list) {
struct irq_chip_type *ct = gc->chip_types;
- if (ct->chip.irq_pm_shutdown)
- ct->chip.irq_pm_shutdown(irq_get_irq_data(gc->irq_base));
+ if (ct->chip.irq_pm_shutdown) {
+ struct irq_data *data = irq_gc_get_irq_data(gc);
+
+ if (data)
+ ct->chip.irq_pm_shutdown(data);
+ }
}
}