alistair23-linux/include/linux/irqdomain.h
Grant Likely cef5075c8c irqdomain: merge linear and tree reverse mappings.
Keeping them separate makes irq_domain more complex and adds a lot of
code (as proven by the diffstat).  Merging them simplifies the whole
scheme.  This change makes it so both the tree and linear methods can be
used by the same irq_domain instance.  If the hwirq is less than the
->linear_size, then the linear map is used to reverse map the hwirq.
Otherwise the radix tree is used.  The test for which map to use is no
more expensive that the existing code, so the performance of fast path
is preserved.

It also means that complex interrupt controllers can use both the
linear map and a tree in the same domain.  This may be useful for an
interrupt controller with a base set of core irqs and a large number
of GPIOs which might be used as irqs.  The linear map could cover the
core irqs, and the tree used for thas irqs.  The linear map could
cover the core irqs, and the tree used for the gpios.

v2: Drop reorganization of revmap data

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>
2013-06-10 11:52:09 +01:00

214 lines
8.1 KiB
C

/*
* irq_domain - IRQ translation domains
*
* Translation infrastructure between hw and linux irq numbers. This is
* helpful for interrupt controllers to implement mapping between hardware
* irq numbers and the Linux irq number space.
*
* irq_domains also have a hook for translating device tree interrupt
* representation into a hardware irq number that can be mapped back to a
* Linux irq number without any extra platform support code.
*
* 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/types.h>
#include <linux/radix-tree.h>
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
* @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 {
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);
};
extern struct irq_domain_ops irq_generic_chip_ops;
struct irq_domain_chip_generic;
/**
* struct irq_domain - Hardware interrupt number translation object
* @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.
* @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
* @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 link;
const char *name;
/* type of reverse mapping_technique */
unsigned int revmap_type;
struct {
struct {
unsigned int size;
} linear;
struct {
unsigned int max_irq;
} nomap;
struct radix_tree_root tree;
} revmap_data;
const struct irq_domain_ops *ops;
void *host_data;
irq_hw_number_t inval_irq;
/* Optional device node pointer */
struct device_node *of_node;
/* Optional pointer to generic interrupt chips */
struct irq_domain_chip_generic *gc;
/* Linear reverse map */
unsigned int linear_revmap[];
};
#define IRQ_DOMAIN_MAP_NOMAP 1 /* no fast reverse mapping */
#define IRQ_DOMAIN_MAP_LINEAR 2 /* linear map of interrupts */
#ifdef CONFIG_IRQ_DOMAIN
struct irq_domain *irq_domain_add_simple(struct device_node *of_node,
unsigned int size,
unsigned int first_irq,
const struct irq_domain_ops *ops,
void *host_data);
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);
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)
{
return irq_domain_add_legacy(of_node, NUM_ISA_INTERRUPTS, 0, 0, ops,
host_data);
}
static inline struct irq_domain *irq_domain_add_tree(struct device_node *of_node,
const struct irq_domain_ops *ops,
void *host_data)
{
return irq_domain_add_linear(of_node, 0, ops, host_data);
}
extern void irq_domain_remove(struct irq_domain *host);
extern int irq_domain_associate_many(struct irq_domain *domain,
unsigned int irq_base,
irq_hw_number_t hwirq_base, int count);
static inline int irq_domain_associate(struct irq_domain *domain, unsigned int irq,
irq_hw_number_t hwirq)
{
return irq_domain_associate_many(domain, irq, hwirq, 1);
}
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 int irq_create_strict_mappings(struct irq_domain *domain,
unsigned int irq_base,
irq_hw_number_t hwirq_base, int count);
static inline int irq_create_identity_mapping(struct irq_domain *host,
irq_hw_number_t hwirq)
{
return irq_create_strict_mappings(host, hwirq, hwirq, 1);
}
extern unsigned int irq_linear_revmap(struct irq_domain *host,
irq_hw_number_t hwirq);
extern const struct irq_domain_ops irq_domain_simple_ops;
/* 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_OF_IRQ)
extern void irq_domain_generate_simple(const struct of_device_id *match,
u64 phys_base, unsigned int irq_start);
#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_OF_IRQ */
#else /* CONFIG_IRQ_DOMAIN */
static inline void irq_dispose_mapping(unsigned int virq) { }
#endif /* !CONFIG_IRQ_DOMAIN */
#endif /* _LINUX_IRQDOMAIN_H */