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
  69extern struct irq_domain_ops irq_generic_chip_ops;
  70
  71struct irq_domain_chip_generic;
  72
  73/**
  74 * struct irq_domain - Hardware interrupt number translation object
  75 * @link: Element in global irq_domain list.
  76 * @name: Name of interrupt domain
  77 * @ops: pointer to irq_domain methods
  78 * @host_data: private data pointer for use by owner.  Not touched by irq_domain
  79 *             core code.
  80 *
  81 * Optional elements
  82 * @of_node: Pointer to device tree nodes associated with the irq_domain. Used
  83 *           when decoding device tree interrupt specifiers.
  84 * @gc: Pointer to a list of generic chips. There is a helper function for
  85 *      setting up one or more generic chips for interrupt controllers
  86 *      drivers using the generic chip library which uses this pointer.
  87 *
  88 * Revmap data, used internally by irq_domain
  89 * @revmap_direct_max_irq: The largest hwirq that can be set for controllers that
  90 *                         support direct mapping
  91 * @revmap_size: Size of the linear map table @linear_revmap[]
  92 * @revmap_tree: Radix map tree for hwirqs that don't fit in the linear map
  93 * @linear_revmap: Linear table of hwirq->virq reverse mappings
  94 */
  95struct irq_domain {
  96        struct list_head link;
  97        const char *name;
  98        const struct irq_domain_ops *ops;
  99        void *host_data;
 100
 101        /* Optional data */
 102        struct device_node *of_node;
 103        struct irq_domain_chip_generic *gc;
 104
 105        /* reverse map data. The linear map gets appended to the irq_domain */
 106        irq_hw_number_t hwirq_max;
 107        unsigned int revmap_direct_max_irq;
 108        unsigned int revmap_size;
 109        struct radix_tree_root revmap_tree;
 110        unsigned int linear_revmap[];
 111};
 112
 113#ifdef CONFIG_IRQ_DOMAIN
 114struct irq_domain *__irq_domain_add(struct device_node *of_node, int size,
 115                                    irq_hw_number_t hwirq_max, int direct_max,
 116                                    const struct irq_domain_ops *ops,
 117                                    void *host_data);
 118struct irq_domain *irq_domain_add_simple(struct device_node *of_node,
 119                                         unsigned int size,
 120                                         unsigned int first_irq,
 121                                         const struct irq_domain_ops *ops,
 122                                         void *host_data);
 123struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
 124                                         unsigned int size,
 125                                         unsigned int first_irq,
 126                                         irq_hw_number_t first_hwirq,
 127                                         const struct irq_domain_ops *ops,
 128                                         void *host_data);
 129extern struct irq_domain *irq_find_host(struct device_node *node);
 130extern void irq_set_default_host(struct irq_domain *host);
 131
 132/**
 133 * irq_domain_add_linear() - Allocate and register a linear revmap irq_domain.
 134 * @of_node: pointer to interrupt controller's device tree node.
 135 * @size: Number of interrupts in the domain.
 136 * @ops: map/unmap domain callbacks
 137 * @host_data: Controller private data pointer
 138 */
 139static inline struct irq_domain *irq_domain_add_linear(struct device_node *of_node,
 140                                         unsigned int size,
 141                                         const struct irq_domain_ops *ops,
 142                                         void *host_data)
 143{
 144        return __irq_domain_add(of_node, size, size, 0, ops, host_data);
 145}
 146static inline struct irq_domain *irq_domain_add_nomap(struct device_node *of_node,
 147                                         unsigned int max_irq,
 148                                         const struct irq_domain_ops *ops,
 149                                         void *host_data)
 150{
 151        return __irq_domain_add(of_node, 0, max_irq, max_irq, ops, host_data);
 152}
 153static inline struct irq_domain *irq_domain_add_legacy_isa(
 154                                struct device_node *of_node,
 155                                const struct irq_domain_ops *ops,
 156                                void *host_data)
 157{
 158        return irq_domain_add_legacy(of_node, NUM_ISA_INTERRUPTS, 0, 0, ops,
 159                                     host_data);
 160}
 161static inline struct irq_domain *irq_domain_add_tree(struct device_node *of_node,
 162                                         const struct irq_domain_ops *ops,
 163                                         void *host_data)
 164{
 165        return __irq_domain_add(of_node, 0, ~0, 0, ops, host_data);
 166}
 167
 168extern void irq_domain_remove(struct irq_domain *host);
 169
 170extern int irq_domain_associate(struct irq_domain *domain, unsigned int irq,
 171                                        irq_hw_number_t hwirq);
 172extern void irq_domain_associate_many(struct irq_domain *domain,
 173                                      unsigned int irq_base,
 174                                      irq_hw_number_t hwirq_base, int count);
 175
 176extern unsigned int irq_create_mapping(struct irq_domain *host,
 177                                       irq_hw_number_t hwirq);
 178extern void irq_dispose_mapping(unsigned int virq);
 179
 180/**
 181 * irq_linear_revmap() - Find a linux irq from a hw irq number.
 182 * @domain: domain owning this hardware interrupt
 183 * @hwirq: hardware irq number in that domain space
 184 *
 185 * This is a fast path alternative to irq_find_mapping() that can be
 186 * called directly by irq controller code to save a handful of
 187 * instructions. It is always safe to call, but won't find irqs mapped
 188 * using the radix tree.
 189 */
 190static inline unsigned int irq_linear_revmap(struct irq_domain *domain,
 191                                             irq_hw_number_t hwirq)
 192{
 193        return hwirq < domain->revmap_size ? domain->linear_revmap[hwirq] : 0;
 194}
 195extern unsigned int irq_find_mapping(struct irq_domain *host,
 196                                     irq_hw_number_t hwirq);
 197extern unsigned int irq_create_direct_mapping(struct irq_domain *host);
 198extern int irq_create_strict_mappings(struct irq_domain *domain,
 199                                      unsigned int irq_base,
 200                                      irq_hw_number_t hwirq_base, int count);
 201
 202static inline int irq_create_identity_mapping(struct irq_domain *host,
 203                                              irq_hw_number_t hwirq)
 204{
 205        return irq_create_strict_mappings(host, hwirq, hwirq, 1);
 206}
 207
 208extern const struct irq_domain_ops irq_domain_simple_ops;
 209
 210/* stock xlate functions */
 211int irq_domain_xlate_onecell(struct irq_domain *d, struct device_node *ctrlr,
 212                        const u32 *intspec, unsigned int intsize,
 213                        irq_hw_number_t *out_hwirq, unsigned int *out_type);
 214int irq_domain_xlate_twocell(struct irq_domain *d, struct device_node *ctrlr,
 215                        const u32 *intspec, unsigned int intsize,
 216                        irq_hw_number_t *out_hwirq, unsigned int *out_type);
 217int irq_domain_xlate_onetwocell(struct irq_domain *d, struct device_node *ctrlr,
 218                        const u32 *intspec, unsigned int intsize,
 219                        irq_hw_number_t *out_hwirq, unsigned int *out_type);
 220
 221#else /* CONFIG_IRQ_DOMAIN */
 222static inline void irq_dispose_mapping(unsigned int virq) { }
 223#endif /* !CONFIG_IRQ_DOMAIN */
 224
 225#endif /* _LINUX_IRQDOMAIN_H */
 226