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 extern struct irq_domain_ops irq_generic_chip_ops;
  70
  71 struct irq_domain_chip_generic;
  72
  73 /**
  74  * struct irq_domain - Hardware interrupt number translation object
  75  * @link: Element in global irq_domain list.
  76  * @revmap_type: Method used for reverse mapping hwirq numbers to linux irq. This
  77  *               will be one of the IRQ_DOMAIN_MAP_* values.
  78  * @revmap_data: Revmap method specific data.
  79  * @ops: pointer to irq_domain methods
  80  * @host_data: private data pointer for use by owner.  Not touched by irq_domain
  81  *             core code.
  82  * @irq_base: Start of irq_desc range assigned to the irq_domain.  The creator
  83  *            of the irq_domain is responsible for allocating the array of
  84  *            irq_desc structures.
  85  * @nr_irq: Number of irqs managed by the irq domain
  86  * @hwirq_base: Starting number for hwirqs managed by the irq domain
  87  * @of_node: (optional) Pointer to device tree nodes associated with the
  88  *           irq_domain.  Used when decoding device tree interrupt specifiers.
  89  */
  90 struct irq_domain {
  91         struct list_head link;
  92
  93         /* type of reverse mapping_technique */
  94         unsigned int revmap_type;
  95         union {
  96                 struct {
  97                         unsigned int size;
  98                         unsigned int first_irq;
  99                         irq_hw_number_t first_hwirq;
 100                 } legacy;
 101                 struct {
 102                         unsigned int size;
 103                         unsigned int *revmap;
 104                 } linear;
 105                 struct {
 106                         unsigned int max_irq;
 107                 } nomap;
 108                 struct radix_tree_root tree;
 109         } revmap_data;
 110         const struct irq_domain_ops *ops;
 111         void *host_data;
 112         irq_hw_number_t inval_irq;
 113
 114         /* Optional device node pointer */
 115         struct device_node *of_node;
 116         /* Optional pointer to generic interrupt chips */
 117         struct irq_domain_chip_generic *gc;
 118 };
 119
 120 #define IRQ_DOMAIN_MAP_LEGACY 0 /* driver allocated fixed range of irqs.
 121                                  * ie. legacy 8259, gets irqs 1..15 */
 122 #define IRQ_DOMAIN_MAP_NOMAP 1 /* no fast reverse mapping */
 123 #define IRQ_DOMAIN_MAP_LINEAR 2 /* linear map of interrupts */
 124 #define IRQ_DOMAIN_MAP_TREE 3 /* radix tree */
 125
 126 #ifdef CONFIG_IRQ_DOMAIN
 127 struct irq_domain *irq_domain_add_simple(struct device_node *of_node,
 128                                          unsigned int size,
 129                                          unsigned int first_irq,
 130                                          const struct irq_domain_ops *ops,
 131                                          void *host_data);
 132 struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
 133                                          unsigned int size,
 134                                          unsigned int first_irq,
 135                                          irq_hw_number_t first_hwirq,
 136                                          const struct irq_domain_ops *ops,
 137                                          void *host_data);
 138 struct irq_domain *irq_domain_add_linear(struct device_node *of_node,
 139                                          unsigned int size,
 140                                          const struct irq_domain_ops *ops,
 141                                          void *host_data);
 142 struct irq_domain *irq_domain_add_nomap(struct device_node *of_node,
 143                                          unsigned int max_irq,
 144                                          const struct irq_domain_ops *ops,
 145                                          void *host_data);
 146 struct irq_domain *irq_domain_add_tree(struct device_node *of_node,
 147                                          const struct irq_domain_ops *ops,
 148                                          void *host_data);
 149
 150 extern struct irq_domain *irq_find_host(struct device_node *node);
 151 extern void irq_set_default_host(struct irq_domain *host);
 152
 153 static 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 }
 161
 162 extern void irq_domain_remove(struct irq_domain *host);
 163
 164 extern int irq_domain_associate_many(struct irq_domain *domain,
 165                                      unsigned int irq_base,
 166                                      irq_hw_number_t hwirq_base, int count);
 167 static inline int irq_domain_associate(struct irq_domain *domain, unsigned int irq,
 168                                         irq_hw_number_t hwirq)
 169 {
 170         return irq_domain_associate_many(domain, irq, hwirq, 1);
 171 }
 172
 173 extern unsigned int irq_create_mapping(struct irq_domain *host,
 174                                        irq_hw_number_t hwirq);
 175 extern void irq_dispose_mapping(unsigned int virq);
 176 extern unsigned int irq_find_mapping(struct irq_domain *host,
 177                                      irq_hw_number_t hwirq);
 178 extern unsigned int irq_create_direct_mapping(struct irq_domain *host);
 179 extern int irq_create_strict_mappings(struct irq_domain *domain,
 180                                       unsigned int irq_base,
 181                                       irq_hw_number_t hwirq_base, int count);
 182
 183 static inline int irq_create_identity_mapping(struct irq_domain *host,
 184                                               irq_hw_number_t hwirq)
 185 {
 186         return irq_create_strict_mappings(host, hwirq, hwirq, 1);
 187 }
 188
 189 extern unsigned int irq_linear_revmap(struct irq_domain *host,
 190                                       irq_hw_number_t hwirq);
 191
 192 extern const struct irq_domain_ops irq_domain_simple_ops;
 193
 194 /* stock xlate functions */
 195 int irq_domain_xlate_onecell(struct irq_domain *d, struct device_node *ctrlr,
 196                         const u32 *intspec, unsigned int intsize,
 197                         irq_hw_number_t *out_hwirq, unsigned int *out_type);
 198 int irq_domain_xlate_twocell(struct irq_domain *d, struct device_node *ctrlr,
 199                         const u32 *intspec, unsigned int intsize,
 200                         irq_hw_number_t *out_hwirq, unsigned int *out_type);
 201 int irq_domain_xlate_onetwocell(struct irq_domain *d, struct device_node *ctrlr,
 202                         const u32 *intspec, unsigned int intsize,
 203                         irq_hw_number_t *out_hwirq, unsigned int *out_type);
 204
 205 #if defined(CONFIG_OF_IRQ)
 206 extern void irq_domain_generate_simple(const struct of_device_id *match,
 207                                         u64 phys_base, unsigned int irq_start);
 208 #else /* CONFIG_OF_IRQ */
 209 static inline void irq_domain_generate_simple(const struct of_device_id *match,
 210                                         u64 phys_base, unsigned int irq_start) { }
 211 #endif /* !CONFIG_OF_IRQ */
 212
 213 #else /* CONFIG_IRQ_DOMAIN */
 214 static inline void irq_dispose_mapping(unsigned int virq) { }
 215 #endif /* !CONFIG_IRQ_DOMAIN */
 216
 217 #endif /* _LINUX_IRQDOMAIN_H */