irqdomain: Port system to new API

The following merge commit chose the irq_domain implementation
from AU_LINUX_ANDROID_ICS.04.00.04.00.126 instead of the version
in v3.4.

commit f132c6cf77251e011e1dad0ec88c0b1fda16d5aa
Merge: 23016de 3f6240f
Author: Steve Muckle <smuckle@codeaurora.org>
Date:   Wed Jun 6 18:30:57 2012 -0700

    Merge commit 'AU_LINUX_ANDROID_ICS.04.00.04.00.126' into
    msm-3.4

Since this version is inconsistent with the upstream,
port the irq_domain framework to the version in v3.4 and
makes all necessary changes to clients that are out of spec.

Details of client ports are below.

-Update the qpnp-int driver for revmap irq_domain API. The revmap
irq_domain implementation introduces a reverse lookup scheme using
a radix tree. This scheme is useful for controllers like qpnp-int
that require a large range of hwirqs.

-Bring the ARM GIC driver up to v3.4, being careful
to port existing CAF changes.

-Partially port the gpio-msm-common driver to the new irq_domain API.
Enable the gpio-msm-common driver to work with the new irq_domain
API using a linear revmap. It is not a full port since irq_domain
is still only registered for Device Tree configurations. It should
be registered even for legacy configurations.

In addition, the irq_domains .map function should be setting all
the fields currently done in msm_gpio_probe(). That's not
currently possible since msm_gpio_probe is invoked
unconditionally - even from Device Tree configurations.

Finally, gpio-msm-common should be converted into a real
platform_device so that probe() is invoked due to driver and
device matching.

Change-Id: I19fa50171bd244759fb6076e3cddc70896d8727b
Signed-off-by: Michael Bohan <mbohan@codeaurora.org>
diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
index ed6bb39..c65740d 100644
--- a/include/linux/irqdomain.h
+++ b/include/linux/irqdomain.h
@@ -9,106 +9,178 @@
  * representation into a hardware irq number that can be mapped back to a
  * Linux irq number without any extra platform support code.
  *
- * irq_domain is expected to be embedded in an interrupt controller's private
- * data structure.
+ * Interrupt controller "domain" data structure. This could be defined as a
+ * irq domain controller. That is, it handles the mapping between hardware
+ * and virtual interrupt numbers for a given interrupt domain. The domain
+ * structure is generally created by the PIC code for a given PIC instance
+ * (though a domain can cover more than one PIC if they have a flat number
+ * model). It's the domain callbacks that are responsible for setting the
+ * irq_chip on a given irq_desc after it's been mapped.
+ *
+ * The host code and data structures are agnostic to whether or not
+ * we use an open firmware device-tree. We do have references to struct
+ * device_node in two places: in irq_find_host() to find the host matching
+ * a given interrupt controller node, and of course as an argument to its
+ * counterpart domain->ops->match() callback. However, those are treated as
+ * generic pointers by the core and the fact that it's actually a device-node
+ * pointer is purely a convention between callers and implementation. This
+ * code could thus be used on other architectures by replacing those two
+ * by some sort of arch-specific void * "token" used to identify interrupt
+ * controllers.
  */
+
 #ifndef _LINUX_IRQDOMAIN_H
 #define _LINUX_IRQDOMAIN_H
 
-#include <linux/irq.h>
-#include <linux/mod_devicetable.h>
+#include <linux/types.h>
+#include <linux/radix-tree.h>
 
-#ifdef CONFIG_IRQ_DOMAIN
 struct device_node;
 struct irq_domain;
+struct of_device_id;
+
+/* Number of irqs reserved for a legacy isa controller */
+#define NUM_ISA_INTERRUPTS	16
 
 /**
  * struct irq_domain_ops - Methods for irq_domain objects
- * @to_irq: (optional) given a local hardware irq number, return the linux
- *          irq number.  If to_irq is not implemented, then the irq_domain
- *          will use this translation: irq = (domain->irq_base + hwirq)
- * @dt_translate: Given a device tree node and interrupt specifier, decode
- *                the hardware irq number and linux irq type value.
+ * @match: Match an interrupt controller device node to a host, returns
+ *         1 on a match
+ * @map: Create or update a mapping between a virtual irq number and a hw
+ *       irq number. This is called only once for a given mapping.
+ * @unmap: Dispose of such a mapping
+ * @xlate: Given a device tree node and interrupt specifier, decode
+ *         the hardware irq number and linux irq type value.
+ *
+ * Functions below are provided by the driver and called whenever a new mapping
+ * is created or an old mapping is disposed. The driver can then proceed to
+ * whatever internal data structures management is required. It also needs
+ * to setup the irq_desc when returning from map().
  */
 struct irq_domain_ops {
-	unsigned int (*to_irq)(struct irq_domain *d, unsigned long hwirq);
-
-#ifdef CONFIG_OF
-	int (*dt_translate)(struct irq_domain *d, struct device_node *node,
-			    const u32 *intspec, unsigned int intsize,
-			    unsigned long *out_hwirq, unsigned int *out_type);
-#endif /* CONFIG_OF */
+	int (*match)(struct irq_domain *d, struct device_node *node);
+	int (*map)(struct irq_domain *d, unsigned int virq, irq_hw_number_t hw);
+	void (*unmap)(struct irq_domain *d, unsigned int virq);
+	int (*xlate)(struct irq_domain *d, struct device_node *node,
+		     const u32 *intspec, unsigned int intsize,
+		     unsigned long *out_hwirq, unsigned int *out_type);
 };
 
 /**
  * struct irq_domain - Hardware interrupt number translation object
- * @list: Element in global irq_domain list.
+ * @link: Element in global irq_domain list.
+ * @revmap_type: Method used for reverse mapping hwirq numbers to linux irq. This
+ *               will be one of the IRQ_DOMAIN_MAP_* values.
+ * @revmap_data: Revmap method specific data.
+ * @ops: pointer to irq_domain methods
+ * @host_data: private data pointer for use by owner.  Not touched by irq_domain
+ *             core code.
  * @irq_base: Start of irq_desc range assigned to the irq_domain.  The creator
  *            of the irq_domain is responsible for allocating the array of
  *            irq_desc structures.
  * @nr_irq: Number of irqs managed by the irq domain
  * @hwirq_base: Starting number for hwirqs managed by the irq domain
- * @ops: pointer to irq_domain methods
- * @priv: private data pointer for use by owner.  Not touched by irq_domain
- *        core code.
  * @of_node: (optional) Pointer to device tree nodes associated with the
  *           irq_domain.  Used when decoding device tree interrupt specifiers.
  */
 struct irq_domain {
-	struct list_head list;
-	unsigned int irq_base;
-	unsigned int nr_irq;
-	unsigned int hwirq_base;
+	struct list_head link;
+
+	/* type of reverse mapping_technique */
+	unsigned int revmap_type;
+	union {
+		struct {
+			unsigned int size;
+			unsigned int first_irq;
+			irq_hw_number_t first_hwirq;
+		} legacy;
+		struct {
+			unsigned int size;
+			unsigned int *revmap;
+		} linear;
+		struct {
+			unsigned int max_irq;
+		} nomap;
+		struct radix_tree_root tree;
+	} revmap_data;
 	const struct irq_domain_ops *ops;
-	void *priv;
+	void *host_data;
+	irq_hw_number_t inval_irq;
+
+	/* Optional device node pointer */
 	struct device_node *of_node;
 };
 
-/**
- * irq_domain_to_irq() - Translate from a hardware irq to a linux irq number
- *
- * Returns the linux irq number associated with a hardware irq.  By default,
- * the mapping is irq == domain->irq_base + hwirq, but this mapping can
- * be overridden if the irq_domain implements a .to_irq() hook.
- */
-static inline unsigned int irq_domain_to_irq(struct irq_domain *d,
-					     unsigned long hwirq)
+#ifdef CONFIG_IRQ_DOMAIN
+struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
+					 unsigned int size,
+					 unsigned int first_irq,
+					 irq_hw_number_t first_hwirq,
+					 const struct irq_domain_ops *ops,
+					 void *host_data);
+struct irq_domain *irq_domain_add_linear(struct device_node *of_node,
+					 unsigned int size,
+					 const struct irq_domain_ops *ops,
+					 void *host_data);
+struct irq_domain *irq_domain_add_nomap(struct device_node *of_node,
+					 unsigned int max_irq,
+					 const struct irq_domain_ops *ops,
+					 void *host_data);
+struct irq_domain *irq_domain_add_tree(struct device_node *of_node,
+					 const struct irq_domain_ops *ops,
+					 void *host_data);
+
+extern struct irq_domain *irq_find_host(struct device_node *node);
+extern void irq_set_default_host(struct irq_domain *host);
+
+static inline struct irq_domain *irq_domain_add_legacy_isa(
+				struct device_node *of_node,
+				const struct irq_domain_ops *ops,
+				void *host_data)
 {
-	if (d->ops->to_irq)
-		return d->ops->to_irq(d, hwirq);
-	if (WARN_ON(hwirq < d->hwirq_base))
-		return 0;
-	return d->irq_base + hwirq - d->hwirq_base;
+	return irq_domain_add_legacy(of_node, NUM_ISA_INTERRUPTS, 0, 0, ops,
+				     host_data);
 }
+extern struct irq_domain *irq_find_host(struct device_node *node);
+extern void irq_set_default_host(struct irq_domain *host);
 
-#define irq_domain_for_each_hwirq(d, hw) \
-	for (hw = d->hwirq_base; hw < d->hwirq_base + d->nr_irq; hw++)
 
-#define irq_domain_for_each_irq(d, hw, irq) \
-	for (hw = d->hwirq_base, irq = irq_domain_to_irq(d, hw); \
-	     hw < d->hwirq_base + d->nr_irq; \
-	     hw++, irq = irq_domain_to_irq(d, hw))
-
+extern unsigned int irq_create_mapping(struct irq_domain *host,
+				       irq_hw_number_t hwirq);
 extern void irq_dispose_mapping(unsigned int virq);
+extern unsigned int irq_find_mapping(struct irq_domain *host,
+				     irq_hw_number_t hwirq);
+extern unsigned int irq_create_direct_mapping(struct irq_domain *host);
+extern void irq_radix_revmap_insert(struct irq_domain *host, unsigned int virq,
+				    irq_hw_number_t hwirq);
+extern unsigned int irq_radix_revmap_lookup(struct irq_domain *host,
+					    irq_hw_number_t hwirq);
+extern unsigned int irq_linear_revmap(struct irq_domain *host,
+				      irq_hw_number_t hwirq);
 
-extern int irq_domain_add(struct irq_domain *domain);
-extern void irq_domain_del(struct irq_domain *domain);
-extern void irq_domain_register(struct irq_domain *domain);
-extern void irq_domain_register_irq(struct irq_domain *domain, int hwirq);
-extern void irq_domain_unregister(struct irq_domain *domain);
-extern void irq_domain_unregister_irq(struct irq_domain *domain, int hwirq);
-extern int irq_domain_find_free_range(unsigned int from, unsigned int cnt);
+extern const struct irq_domain_ops irq_domain_simple_ops;
 
-extern struct irq_domain_ops irq_domain_simple_ops;
-#endif /* CONFIG_IRQ_DOMAIN */
+/* stock xlate functions */
+int irq_domain_xlate_onecell(struct irq_domain *d, struct device_node *ctrlr,
+			const u32 *intspec, unsigned int intsize,
+			irq_hw_number_t *out_hwirq, unsigned int *out_type);
+int irq_domain_xlate_twocell(struct irq_domain *d, struct device_node *ctrlr,
+			const u32 *intspec, unsigned int intsize,
+			irq_hw_number_t *out_hwirq, unsigned int *out_type);
+int irq_domain_xlate_onetwocell(struct irq_domain *d, struct device_node *ctrlr,
+			const u32 *intspec, unsigned int intsize,
+			irq_hw_number_t *out_hwirq, unsigned int *out_type);
 
-#if defined(CONFIG_IRQ_DOMAIN) && defined(CONFIG_OF_IRQ)
-extern void irq_domain_add_simple(struct device_node *controller, int irq_base);
+#if defined(CONFIG_OF_IRQ)
 extern void irq_domain_generate_simple(const struct of_device_id *match,
 					u64 phys_base, unsigned int irq_start);
-#else /* CONFIG_IRQ_DOMAIN && CONFIG_OF_IRQ */
+#else /* CONFIG_OF_IRQ */
 static inline void irq_domain_generate_simple(const struct of_device_id *match,
 					u64 phys_base, unsigned int irq_start) { }
-#endif /* CONFIG_IRQ_DOMAIN && CONFIG_OF_IRQ */
+#endif /* !CONFIG_OF_IRQ */
+
+#else /* CONFIG_IRQ_DOMAIN */
+static inline void irq_dispose_mapping(unsigned int virq) { }
+#endif /* !CONFIG_IRQ_DOMAIN */
 
 #endif /* _LINUX_IRQDOMAIN_H */