LXR linux/include/linux/irqdomain.h

   1/*
   2 * irq_domain - IRQ translation domains
   3 *
   4 * Translation infrastructure between hw and linux irq numbers.  This is
   5 * helpful for interrupt controllers to implement mapping between hardware
   6 * irq numbers and the Linux irq number space.
   7 *
   8 * irq_domains also have a hook for translating device tree interrupt
   9 * representation into a hardware irq number that can be mapped back to a
  10 * Linux irq number without any extra platform support code.
  11 *
  12 * Interrupt controller "domain" data structure. This could be defined as a
  13 * irq domain controller. That is, it handles the mapping between hardware
  14 * and virtual interrupt numbers for a given interrupt domain. The domain
  15 * structure is generally created by the PIC code for a given PIC instance
  16 * (though a domain can cover more than one PIC if they have a flat number
  17 * model). It's the domain callbacks that are responsible for setting the
  18 * irq_chip on a given irq_desc after it's been mapped.
  19 *
  20 * The host code and data structures are agnostic to whether or not
  21 * we use an open firmware device-tree. We do have references to struct
  22 * device_node in two places: in irq_find_host() to find the host matching
  23 * a given interrupt controller node, and of course as an argument to its
  24 * counterpart domain->ops->match() callback. However, those are treated as
  25 * generic pointers by the core and the fact that it's actually a device-node
  26 * pointer is purely a convention between callers and implementation. This
  27 * code could thus be used on other architectures by replacing those two
  28 * by some sort of arch-specific void * "token" used to identify interrupt
  29 * controllers.
  30 */
  31
  32#ifndef _LINUX_IRQDOMAIN_H
  33#define _LINUX_IRQDOMAIN_H
  34
  35#include <linux/types.h>
  36#include <linux/radix-tree.h>
  37
  38struct device_node;
  39struct irq_domain;
  40struct of_device_id;
  41
  42/* Number of irqs reserved for a legacy isa controller */
  43#define NUM_ISA_INTERRUPTS      16
  44
  45/**
  46 * struct irq_domain_ops - Methods for irq_domain objects
  47 * @match: Match an interrupt controller device node to a host, returns
  48 *         1 on a match
  49 * @map: Create or update a mapping between a virtual irq number and a hw
  50 *       irq number. This is called only once for a given mapping.
  51 * @unmap: Dispose of such a mapping
  52 * @xlate: Given a device tree node and interrupt specifier, decode
  53 *         the hardware irq number and linux irq type value.
  54 *
  55 * Functions below are provided by the driver and called whenever a new mapping
  56 * is created or an old mapping is disposed. The driver can then proceed to
  57 * whatever internal data structures management is required. It also needs
  58 * to setup the irq_desc when returning from map().
  59 */
  60struct irq_domain_ops {
  61        int (*match)(struct irq_domain *d, struct device_node *node);
  62        int (*map)(struct irq_domain *d, unsigned int virq, irq_hw_number_t hw);
  63        void (*unmap)(struct irq_domain *d, unsigned int virq);
  64        int (*xlate)(struct irq_domain *d, struct device_node *node,
  65                     const u32 *intspec, unsigned int intsize,
  66                     unsigned long *out_hwirq, unsigned int *out_type);
  67};
  68
  69/**
  70 * struct irq_domain - Hardware interrupt number translation object
  71 * @link: Element in global irq_domain list.
  72 * @revmap_type: Method used for reverse mapping hwirq numbers to linux irq. This
  73 *               will be one of the IRQ_DOMAIN_MAP_* values.
  74 * @revmap_data: Revmap method specific data.
  75 * @ops: pointer to irq_domain methods
  76 * @host_data: private data pointer for use by owner.  Not touched by irq_domain
  77 *             core code.
  78 * @irq_base: Start of irq_desc range assigned to the irq_domain.  The creator
  79 *            of the irq_domain is responsible for allocating the array of
  80 *            irq_desc structures.
  81 * @nr_irq: Number of irqs managed by the irq domain
  82 * @hwirq_base: Starting number for hwirqs managed by the irq domain
  83 * @of_node: (optional) Pointer to device tree nodes associated with the
  84 *           irq_domain.  Used when decoding device tree interrupt specifiers.
  85 */
  86struct irq_domain {
  87        struct list_head link;
  88
  89        /* type of reverse mapping_technique */
  90        unsigned int revmap_type;
  91        union {
  92                struct {
  93                        unsigned int size;
  94                        unsigned int first_irq;
  95                        irq_hw_number_t first_hwirq;
  96                } legacy;
  97                struct {
  98                        unsigned int size;
  99                        unsigned int *revmap;
 100                } linear;
 101                struct {
 102                        unsigned int max_irq;
 103                } nomap;
 104                struct radix_tree_root tree;
 105        } revmap_data;
 106        const struct irq_domain_ops *ops;
 107        void *host_data;
 108        irq_hw_number_t inval_irq;
 109
 110        /* Optional device node pointer */
 111        struct device_node *of_node;
 112};
 113
 114#ifdef CONFIG_IRQ_DOMAIN
 115struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
 116                                         unsigned int size,
 117                                         unsigned int first_irq,
 118                                         irq_hw_number_t first_hwirq,
 119                                         const struct irq_domain_ops *ops,
 120                                         void *host_data);
 121struct irq_domain *irq_domain_add_linear(struct device_node *of_node,
 122                                         unsigned int size,
 123                                         const struct irq_domain_ops *ops,
 124                                         void *host_data);
 125struct irq_domain *irq_domain_add_nomap(struct device_node *of_node,
 126                                         unsigned int max_irq,
 127                                         const struct irq_domain_ops *ops,
 128                                         void *host_data);
 129struct irq_domain *irq_domain_add_tree(struct device_node *of_node,
 130                                         const struct irq_domain_ops *ops,
 131                                         void *host_data);
 132
 133extern struct irq_domain *irq_find_host(struct device_node *node);
 134extern void irq_set_default_host(struct irq_domain *host);
 135
 136static inline struct irq_domain *irq_domain_add_legacy_isa(
 137                                struct device_node *of_node,
 138                                const struct irq_domain_ops *ops,
 139                                void *host_data)
 140{
 141        return irq_domain_add_legacy(of_node, NUM_ISA_INTERRUPTS, 0, 0, ops,
 142                                     host_data);
 143}
 144
 145extern void irq_domain_remove(struct irq_domain *host);
 146
 147extern unsigned int irq_create_mapping(struct irq_domain *host,
 148                                       irq_hw_number_t hwirq);
 149extern void irq_dispose_mapping(unsigned int virq);
 150extern unsigned int irq_find_mapping(struct irq_domain *host,
 151                                     irq_hw_number_t hwirq);
 152extern unsigned int irq_create_direct_mapping(struct irq_domain *host);
 153extern void irq_radix_revmap_insert(struct irq_domain *host, unsigned int virq,
 154                                    irq_hw_number_t hwirq);
 155extern unsigned int irq_radix_revmap_lookup(struct irq_domain *host,
 156                                            irq_hw_number_t hwirq);
 157extern unsigned int irq_linear_revmap(struct irq_domain *host,
 158                                      irq_hw_number_t hwirq);
 159
 160extern const struct irq_domain_ops irq_domain_simple_ops;
 161
 162/* stock xlate functions */
 163int irq_domain_xlate_onecell(struct irq_domain *d, struct device_node *ctrlr,
 164                        const u32 *intspec, unsigned int intsize,
 165                        irq_hw_number_t *out_hwirq, unsigned int *out_type);
 166int irq_domain_xlate_twocell(struct irq_domain *d, struct device_node *ctrlr,
 167                        const u32 *intspec, unsigned int intsize,
 168                        irq_hw_number_t *out_hwirq, unsigned int *out_type);
 169int irq_domain_xlate_onetwocell(struct irq_domain *d, struct device_node *ctrlr,
 170                        const u32 *intspec, unsigned int intsize,
 171                        irq_hw_number_t *out_hwirq, unsigned int *out_type);
 172
 173#if defined(CONFIG_OF_IRQ)
 174extern void irq_domain_generate_simple(const struct of_device_id *match,
 175                                        u64 phys_base, unsigned int irq_start);
 176#else /* CONFIG_OF_IRQ */
 177static inline void irq_domain_generate_simple(const struct of_device_id *match,
 178                                        u64 phys_base, unsigned int irq_start) { }
 179#endif /* !CONFIG_OF_IRQ */
 180
 181#else /* CONFIG_IRQ_DOMAIN */
 182static inline void irq_dispose_mapping(unsigned int virq) { }
 183#endif /* !CONFIG_IRQ_DOMAIN */
 184
 185#endif /* _LINUX_IRQDOMAIN_H */
 186