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
  38 struct device_node;
  39 struct irq_domain;
  40 struct 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  */
  60 struct 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  */
  86 struct 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
 115 struct irq_domain *irq_domain_add_simple(struct device_node *of_node,
 116                                          unsigned int size,
 117                                          unsigned int first_irq,
 118                                          const struct irq_domain_ops *ops,
 119                                          void *host_data);
 120 struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
 121                                          unsigned int size,
 122                                          unsigned int first_irq,
 123                                          irq_hw_number_t first_hwirq,
 124                                          const struct irq_domain_ops *ops,
 125                                          void *host_data);
 126 struct irq_domain *irq_domain_add_linear(struct device_node *of_node,
 127                                          unsigned int size,
 128                                          const struct irq_domain_ops *ops,
 129                                          void *host_data);
 130 struct irq_domain *irq_domain_add_nomap(struct device_node *of_node,
 131                                          unsigned int max_irq,
 132                                          const struct irq_domain_ops *ops,
 133                                          void *host_data);
 134 struct irq_domain *irq_domain_add_tree(struct device_node *of_node,
 135                                          const struct irq_domain_ops *ops,
 136                                          void *host_data);
 137
 138 extern struct irq_domain *irq_find_host(struct device_node *node);
 139 extern void irq_set_default_host(struct irq_domain *host);
 140
 141 static inline struct irq_domain *irq_domain_add_legacy_isa(
 142                                 struct device_node *of_node,
 143                                 const struct irq_domain_ops *ops,
 144                                 void *host_data)
 145 {
 146         return irq_domain_add_legacy(of_node, NUM_ISA_INTERRUPTS, 0, 0, ops,
 147                                      host_data);
 148 }
 149
 150 extern void irq_domain_remove(struct irq_domain *host);
 151
 152 extern int irq_domain_associate_many(struct irq_domain *domain,
 153                                      unsigned int irq_base,
 154                                      irq_hw_number_t hwirq_base, int count);
 155 static inline int irq_domain_associate(struct irq_domain *domain, unsigned int irq,
 156                                         irq_hw_number_t hwirq)
 157 {
 158         return irq_domain_associate_many(domain, irq, hwirq, 1);
 159 }
 160
 161 extern unsigned int irq_create_mapping(struct irq_domain *host,
 162                                        irq_hw_number_t hwirq);
 163 extern void irq_dispose_mapping(unsigned int virq);
 164 extern unsigned int irq_find_mapping(struct irq_domain *host,
 165                                      irq_hw_number_t hwirq);
 166 extern unsigned int irq_create_direct_mapping(struct irq_domain *host);
 167 extern int irq_create_strict_mappings(struct irq_domain *domain,
 168                                       unsigned int irq_base,
 169                                       irq_hw_number_t hwirq_base, int count);
 170
 171 static inline int irq_create_identity_mapping(struct irq_domain *host,
 172                                               irq_hw_number_t hwirq)
 173 {
 174         return irq_create_strict_mappings(host, hwirq, hwirq, 1);
 175 }
 176
 177 extern unsigned int irq_linear_revmap(struct irq_domain *host,
 178                                       irq_hw_number_t hwirq);
 179
 180 extern const struct irq_domain_ops irq_domain_simple_ops;
 181
 182 /* stock xlate functions */
 183 int irq_domain_xlate_onecell(struct irq_domain *d, struct device_node *ctrlr,
 184                         const u32 *intspec, unsigned int intsize,
 185                         irq_hw_number_t *out_hwirq, unsigned int *out_type);
 186 int irq_domain_xlate_twocell(struct irq_domain *d, struct device_node *ctrlr,
 187                         const u32 *intspec, unsigned int intsize,
 188                         irq_hw_number_t *out_hwirq, unsigned int *out_type);
 189 int irq_domain_xlate_onetwocell(struct irq_domain *d, struct device_node *ctrlr,
 190                         const u32 *intspec, unsigned int intsize,
 191                         irq_hw_number_t *out_hwirq, unsigned int *out_type);
 192
 193 #if defined(CONFIG_OF_IRQ)
 194 extern void irq_domain_generate_simple(const struct of_device_id *match,
 195                                         u64 phys_base, unsigned int irq_start);
 196 #else /* CONFIG_OF_IRQ */
 197 static inline void irq_domain_generate_simple(const struct of_device_id *match,
 198                                         u64 phys_base, unsigned int irq_start) { }
 199 #endif /* !CONFIG_OF_IRQ */
 200
 201 #else /* CONFIG_IRQ_DOMAIN */
 202 static inline void irq_dispose_mapping(unsigned int virq) { }
 203 #endif /* !CONFIG_IRQ_DOMAIN */
 204
 205 #endif /* _LINUX_IRQDOMAIN_H */