irq_domain/powerpc: Use common irq_domain structure instead of irq_host

This patch drops the powerpc-specific irq_host structures and uses the common
irq_domain strucutres defined in linux/irqdomain.h.  It also fixes all
the users to use the new structure names.

Renaming irq_host to irq_domain has been discussed for a long time, and this
patch is a step in the process of generalizing the powerpc virq code to be
usable by all architecture.

An astute reader will notice that this patch actually removes the irq_host
structure instead of renaming it.  This is because the irq_domain structure
already exists in include/linux/irqdomain.h and has the needed data members.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>

arch/powerpc/include/asm/ehv_pic.h

@@ -25,7 +25,7 @@
 
 struct ehv_pic {
 	/* The remapper for this EHV_PIC */
-	struct irq_host	*irqhost;
+	struct irq_domain	*irqhost;
 
 	/* The "linux" controller struct */
 	struct irq_chip	hc_irq;

arch/powerpc/include/asm/i8259.h

@@ -6,7 +6,7 @@
 
 extern void i8259_init(struct device_node *node, unsigned long intack_addr);
 extern unsigned int i8259_irq(void);
-extern struct irq_host *i8259_get_host(void);
+extern struct irq_domain *i8259_get_host(void);
 
 #endif /* __KERNEL__ */
 #endif /* _ASM_POWERPC_I8259_H */

arch/powerpc/include/asm/irq.h

@@ -9,6 +9,7 @@
  * 2 of the License, or (at your option) any later version.
  */
 
+#include <linux/irqdomain.h>
 #include <linux/threads.h>
 #include <linux/list.h>
 #include <linux/radix-tree.h>
@@ -41,20 +42,7 @@ extern atomic_t ppc_n_lost_interrupts;
 /* Same thing, used by the generic IRQ code */
 #define NR_IRQS_LEGACY		NUM_ISA_INTERRUPTS
 
-/* This type is the placeholder for a hardware interrupt number. It has to
- * be big enough to enclose whatever representation is used by a given
- * platform.
- */
-typedef unsigned long irq_hw_number_t;
-
-/* Interrupt controller "host" 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 host
- * structure is generally created by the PIC code for a given PIC instance
- * (though a host can cover more than one PIC if they have a flat number
- * model). It's the host 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 fairly agnostic to the fact that
  * 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
@@ -66,98 +54,40 @@ typedef unsigned long irq_hw_number_t;
  * by some sort of arch-specific void * "token" used to identify interrupt
  * controllers.
  */
-struct irq_host;
-struct radix_tree_root;
-
-/* Functions below are provided by the host and called whenever a new mapping
- * is created or an old mapping is disposed. The host 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_host_ops {
-	/* Match an interrupt controller device node to a host, returns
-	 * 1 on a match
-	 */
-	int (*match)(struct irq_host *h, struct device_node *node);
-
-	/* Create or update a mapping between a virtual irq number and a hw
-	 * irq number. This is called only once for a given mapping.
-	 */
-	int (*map)(struct irq_host *h, unsigned int virq, irq_hw_number_t hw);
-
-	/* Dispose of such a mapping */
-	void (*unmap)(struct irq_host *h, unsigned int virq);
-
-	/* Translate device-tree interrupt specifier from raw format coming
-	 * from the firmware to a irq_hw_number_t (interrupt line number) and
-	 * type (sense) that can be passed to set_irq_type(). In the absence
-	 * of this callback, irq_create_of_mapping() and irq_of_parse_and_map()
-	 * will return the hw number in the first cell and IRQ_TYPE_NONE for
-	 * the type (which amount to keeping whatever default value the
-	 * interrupt controller has for that line)
-	 */
-	int (*xlate)(struct irq_host *h, struct device_node *ctrler,
-		     const u32 *intspec, unsigned int intsize,
-		     irq_hw_number_t *out_hwirq, unsigned int *out_type);
-};
-
-struct irq_host {
-	struct list_head	link;
-
-	/* type of reverse mapping technique */
-	unsigned int		revmap_type;
-#define IRQ_HOST_MAP_LEGACY     0 /* legacy 8259, gets irqs 1..15 */
-#define IRQ_HOST_MAP_NOMAP	1 /* no fast reverse mapping */
-#define IRQ_HOST_MAP_LINEAR	2 /* linear map of interrupts */
-#define IRQ_HOST_MAP_TREE	3 /* radix tree */
-	union {
-		struct {
-			unsigned int size;
-			unsigned int *revmap;
-		} linear;
-		struct radix_tree_root tree;
-	} revmap_data;
-	struct irq_host_ops	*ops;
-	void			*host_data;
-	irq_hw_number_t		inval_irq;
-
-	/* Optional device node pointer */
-	struct device_node	*of_node;
-};
 
 struct irq_data;
 extern irq_hw_number_t irqd_to_hwirq(struct irq_data *d);
 extern irq_hw_number_t virq_to_hw(unsigned int virq);
-extern bool virq_is_host(unsigned int virq, struct irq_host *host);
+extern bool virq_is_host(unsigned int virq, struct irq_domain *host);
 
 /**
- * irq_alloc_host - Allocate a new irq_host data structure
+ * irq_alloc_host - Allocate a new irq_domain data structure
  * @of_node: optional device-tree node of the interrupt controller
  * @revmap_type: type of reverse mapping to use
- * @revmap_arg: for IRQ_HOST_MAP_LINEAR linear only: size of the map
+ * @revmap_arg: for IRQ_DOMAIN_MAP_LINEAR linear only: size of the map
  * @ops: map/unmap host callbacks
  * @inval_irq: provide a hw number in that host space that is always invalid
  *
- * Allocates and initialize and irq_host structure. Note that in the case of
- * IRQ_HOST_MAP_LEGACY, the map() callback will be called before this returns
+ * Allocates and initialize and irq_domain structure. Note that in the case of
+ * IRQ_DOMAIN_MAP_LEGACY, the map() callback will be called before this returns
  * for all legacy interrupts except 0 (which is always the invalid irq for
- * a legacy controller). For a IRQ_HOST_MAP_LINEAR, the map is allocated by
- * this call as well. For a IRQ_HOST_MAP_TREE, the radix tree will be allocated
+ * a legacy controller). For a IRQ_DOMAIN_MAP_LINEAR, the map is allocated by
+ * this call as well. For a IRQ_DOMAIN_MAP_TREE, the radix tree will be allocated
  * later during boot automatically (the reverse mapping will use the slow path
  * until that happens).
  */
-extern struct irq_host *irq_alloc_host(struct device_node *of_node,
+extern struct irq_domain *irq_alloc_host(struct device_node *of_node,
 				       unsigned int revmap_type,
 				       unsigned int revmap_arg,
-				       struct irq_host_ops *ops,
+				       struct irq_domain_ops *ops,
 				       irq_hw_number_t inval_irq);
 
 
 /**
  * irq_find_host - Locates a host for a given device node
  * @node: device-tree node of the interrupt controller
  */
-extern struct irq_host *irq_find_host(struct device_node *node);
+extern struct irq_domain *irq_find_host(struct device_node *node);
 
 
 /**
@@ -169,7 +99,7 @@ extern struct irq_host *irq_find_host(struct device_node *node);
  * platforms that want to manipulate a few hard coded interrupt numbers that
  * aren't properly represented in the device-tree.
  */
-extern void irq_set_default_host(struct irq_host *host);
+extern void irq_set_default_host(struct irq_domain *host);
 
 
 /**
@@ -192,7 +122,7 @@ extern void irq_set_virq_count(unsigned int count);
  * If the sense/trigger is to be specified, set_irq_type() should be called
  * on the number returned from that call.
  */
-extern unsigned int irq_create_mapping(struct irq_host *host,
+extern unsigned int irq_create_mapping(struct irq_domain *host,
 				       irq_hw_number_t hwirq);
 
 
@@ -211,7 +141,7 @@ extern void irq_dispose_mapping(unsigned int virq);
  * irq controller implementation directly calls the appropriate low level
  * mapping function.
  */
-extern unsigned int irq_find_mapping(struct irq_host *host,
+extern unsigned int irq_find_mapping(struct irq_domain *host,
 				     irq_hw_number_t hwirq);
 
 /**
@@ -222,7 +152,7 @@ extern unsigned int irq_find_mapping(struct irq_host *host,
  * interrupt numbers they generate. In such a case it's simplest to use
  * the linux virq as the hardware interrupt number.
  */
-extern unsigned int irq_create_direct_mapping(struct irq_host *host);
+extern unsigned int irq_create_direct_mapping(struct irq_domain *host);
 
 /**
  * irq_radix_revmap_insert - Insert a hw irq to linux virq number mapping.
@@ -233,7 +163,7 @@ extern unsigned int irq_create_direct_mapping(struct irq_host *host);
  * This is for use by irq controllers that use a radix tree reverse
  * mapping for fast lookup.
  */
-extern void irq_radix_revmap_insert(struct irq_host *host, unsigned int virq,
+extern void irq_radix_revmap_insert(struct irq_domain *host, unsigned int virq,
 				    irq_hw_number_t hwirq);
 
 /**
@@ -244,7 +174,7 @@ extern void irq_radix_revmap_insert(struct irq_host *host, unsigned int virq,
  * This is a fast path, for use by irq controller code that uses radix tree
  * revmaps
  */
-extern unsigned int irq_radix_revmap_lookup(struct irq_host *host,
+extern unsigned int irq_radix_revmap_lookup(struct irq_domain *host,
 					    irq_hw_number_t hwirq);
 
 /**
@@ -257,7 +187,7 @@ extern unsigned int irq_radix_revmap_lookup(struct irq_host *host,
  * yet and will create the revmap entry with appropriate locking
  */
 
-extern unsigned int irq_linear_revmap(struct irq_host *host,
+extern unsigned int irq_linear_revmap(struct irq_domain *host,
 				      irq_hw_number_t hwirq);
 
 
@@ -272,7 +202,7 @@ extern unsigned int irq_linear_revmap(struct irq_host *host,
  * and that can be used by some irq controllers implementations for things
  * like allocating ranges of numbers for MSIs. The revmaps are left untouched.
  */
-extern unsigned int irq_alloc_virt(struct irq_host *host,
+extern unsigned int irq_alloc_virt(struct irq_domain *host,
 				   unsigned int count,
 				   unsigned int hint);
 

arch/powerpc/include/asm/mpic.h

@@ -255,7 +255,7 @@ struct mpic
 	struct device_node *node;
 
 	/* The remapper for this MPIC */
-	struct irq_host		*irqhost;
+	struct irq_domain	*irqhost;
 
 	/* The "linux" controller struct */
 	struct irq_chip		hc_irq;

arch/powerpc/include/asm/xics.h

@@ -86,7 +86,7 @@ struct ics {
 extern unsigned int xics_default_server;
 extern unsigned int xics_default_distrib_server;
 extern unsigned int xics_interrupt_server_size;
-extern struct irq_host *xics_host;
+extern struct irq_domain *xics_host;
 
 struct xics_cppr {
 	unsigned char stack[MAX_NUM_PRIORITIES];