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#ifdef __KERNEL__
#ifndef _ASM_POWERPC_IRQ_H
#define _ASM_POWERPC_IRQ_H
/*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/threads.h>
#include <linux/list.h>
#include <linux/radix-tree.h>
#include <asm/types.h>
#include <asm/atomic.h>
#define get_irq_desc(irq) (&irq_desc[(irq)])
/* Define a way to iterate across irqs. */
#define for_each_irq(i) \
for ((i) = 0; (i) < NR_IRQS; ++(i))
extern atomic_t ppc_n_lost_interrupts;
#ifdef CONFIG_PPC_MERGE
/* This number is used when no interrupt has been assigned */
#define NO_IRQ (0)
/* This is a special irq number to return from get_irq() to tell that
* no interrupt happened _and_ ignore it (don't count it as bad). Some
* platforms like iSeries rely on that.
*/
#define NO_IRQ_IGNORE ((unsigned int)-1)
/* Total number of virq in the platform (make it a CONFIG_* option ? */
#define NR_IRQS 512
/* Number of irqs reserved for the legacy controller */
#define NUM_ISA_INTERRUPTS 16
/* 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
* a given interrupt controller node, and of course as an argument to its
* counterpart host->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.
*/
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);
/* Update of such a mapping */
void (*remap)(struct irq_host *h, unsigned int virq, irq_hw_number_t hw);
/* 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,
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;
};
/* The main irq map itself is an array of NR_IRQ entries containing the
* associate host and irq number. An entry with a host of NULL is free.
* An entry can be allocated if it's free, the allocator always then sets
* hwirq first to the host's invalid irq number and then fills ops.
*/
struct irq_map_entry {
irq_hw_number_t hwirq;
struct irq_host *host;
};
extern struct irq_map_entry irq_map[NR_IRQS];
extern irq_hw_number_t virq_to_hw(unsigned int virq);
/**
* irq_alloc_host - Allocate a new irq_host data structure
* @node: 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
* @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
* 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
* later during boot automatically (the reverse mapping will use the slow path
* until that happens).
*/
extern struct irq_host *irq_alloc_host(unsigned int revmap_type,
unsigned int revmap_arg,
struct irq_host_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);
/**
* irq_set_default_host - Set a "default" host
* @host: default host pointer
*
* For convenience, it's possible to set a "default" host that will be used
* whenever NULL is passed to irq_create_mapping(). It makes life easier for
* 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);
/**
* irq_set_virq_count - Set the maximum number of virt irqs
* @count: number of linux virtual irqs, capped with NR_IRQS
*
* This is mainly for use by platforms like iSeries who want to program
* the virtual irq number in the controller to avoid the reverse mapping
*/
extern void irq_set_virq_count(unsigned int count);
/**
* irq_create_mapping - Map a hardware interrupt into linux virq space
* @host: host owning this hardware interrupt or NULL for default host
* @hwirq: hardware irq number in that host space
*
* Only one mapping per hardware interrupt is permitted. Returns a linux
* virq number.
* 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,
irq_hw_number_t hwirq);
/**
* irq_dispose_mapping - Unmap an interrupt
* @virq: linux virq number of the interrupt to unmap
*/
extern void irq_dispose_mapping(unsigned int virq);
/**
* irq_find_mapping - Find a linux virq from an hw irq number.
* @host: host owning this hardware interrupt
* @hwirq: hardware irq number in that host space
*
* This is a slow path, for use by generic code. It's expected that an
* irq controller implementation directly calls the appropriate low level
* mapping function.
*/
extern unsigned int irq_find_mapping(struct irq_host *host,
irq_hw_number_t hwirq);
/**
* irq_create_direct_mapping - Allocate a virq for direct mapping
* @host: host to allocate the virq for or NULL for default host
*
* This routine is used for irq controllers which can choose the hardware
* 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);
/**
* irq_radix_revmap - Find a linux virq from a hw irq number.
* @host: host owning this hardware interrupt
* @hwirq: hardware irq number in that host space
*
* This is a fast path, for use by irq controller code that uses radix tree
* revmaps
*/
extern unsigned int irq_radix_revmap(struct irq_host *host,
irq_hw_number_t hwirq);
/**
* irq_linear_revmap - Find a linux virq from a hw irq number.
* @host: host owning this hardware interrupt
* @hwirq: hardware irq number in that host space
*
* This is a fast path, for use by irq controller code that uses linear
* revmaps. It does fallback to the slow path if the revmap doesn't exist
* yet and will create the revmap entry with appropriate locking
*/
extern unsigned int irq_linear_revmap(struct irq_host *host,
irq_hw_number_t hwirq);
/**
* irq_alloc_virt - Allocate virtual irq numbers
* @host: host owning these new virtual irqs
* @count: number of consecutive numbers to allocate
* @hint: pass a hint number, the allocator will try to use a 1:1 mapping
*
* This is a low level function that is used internally by irq_create_mapping()
* 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,
unsigned int count,
unsigned int hint);
/**
* irq_free_virt - Free virtual irq numbers
* @virq: virtual irq number of the first interrupt to free
* @count: number of interrupts to free
*
* This function is the opposite of irq_alloc_virt. It will not clear reverse
* maps, this should be done previously by unmap'ing the interrupt. In fact,
* all interrupts covered by the range being freed should have been unmapped
* prior to calling this.
*/
extern void irq_free_virt(unsigned int virq, unsigned int count);
/* -- OF helpers -- */
/* irq_create_of_mapping - Map a hardware interrupt into linux virq space
* @controller: Device node of the interrupt controller
* @inspec: Interrupt specifier from the device-tree
* @intsize: Size of the interrupt specifier from t
|