include/linux/irq.h

   1 #ifndef __irq_h
   2 #define __irq_h
   3
   4 /*
   5  * Please do not include this file in generic code.  There is currently
   6  * no requirement for any architecture to implement anything held
   7  * within this file.
   8  *
   9  * Thanks. --rmk
  10  */
  11
  12 #include <linux/config.h>
  13 #include <asm/smp.h>            /* cpu_online_map */
  14
  15 #if !defined(CONFIG_ARCH_S390)
  16
  17 #include <linux/linkage.h>
  18 #include <linux/cache.h>
  19 #include <linux/spinlock.h>
  20 #include <linux/cpumask.h>
  21
  22 #include <asm/irq.h>
  23 #include <asm/ptrace.h>
  24
  25 /*
  26  * IRQ line status.
  27  */
  28 #define IRQ_INPROGRESS  1       /* IRQ handler active - do not enter! */
  29 #define IRQ_DISABLED    2       /* IRQ disabled - do not enter! */
  30 #define IRQ_PENDING     4       /* IRQ pending - replay on enable */
  31 #define IRQ_REPLAY      8       /* IRQ has been replayed but not acked yet */
  32 #define IRQ_AUTODETECT  16      /* IRQ is being autodetected */
  33 #define IRQ_WAITING     32      /* IRQ not yet seen - for autodetection */
  34 #define IRQ_LEVEL       64      /* IRQ level triggered */
  35 #define IRQ_MASKED      128     /* IRQ masked - shouldn't be seen again */
  36 #if defined(ARCH_HAS_IRQ_PER_CPU)
  37 # define IRQ_PER_CPU    256     /* IRQ is per CPU */
  38 # define CHECK_IRQ_PER_CPU(var) ((var) & IRQ_PER_CPU)
  39 #else
  40 # define CHECK_IRQ_PER_CPU(var) 0
  41 #endif
  42
  43 /*
  44  * Interrupt controller descriptor. This is all we need
  45  * to describe about the low-level hardware.
  46  */
  47 struct hw_interrupt_type {
  48         const char * typename;
  49         unsigned int (*startup)(unsigned int irq);
  50         void (*shutdown)(unsigned int irq);
  51         void (*enable)(unsigned int irq);
  52         void (*disable)(unsigned int irq);
  53         void (*ack)(unsigned int irq);
  54         void (*end)(unsigned int irq);
  55         void (*set_affinity)(unsigned int irq, cpumask_t dest);
  56         /* Currently used only by UML, might disappear one day.*/
  57 #ifdef CONFIG_IRQ_RELEASE_METHOD
  58         void (*release)(unsigned int irq, void *dev_id);
  59 #endif
  60 };
  61
  62 typedef struct hw_interrupt_type  hw_irq_controller;
  63
  64 /*
  65  * This is the "IRQ descriptor", which contains various information
  66  * about the irq, including what kind of hardware handling it has,
  67  * whether it is disabled etc etc.
  68  *
  69  * Pad this out to 32 bytes for cache and indexing reasons.
  70  */
  71 typedef struct irq_desc {
  72         hw_irq_controller *handler;
  73         void *handler_data;
  74         struct irqaction *action;       /* IRQ action list */
  75         unsigned int status;            /* IRQ status */
  76         unsigned int depth;             /* nested irq disables */
  77         unsigned int irq_count;         /* For detecting broken interrupts */
  78         unsigned int irqs_unhandled;
  79         spinlock_t lock;
  80 #if defined (CONFIG_GENERIC_PENDING_IRQ) || defined (CONFIG_IRQBALANCE)
  81         unsigned int move_irq;          /* Flag need to re-target intr dest*/
  82 #endif
  83 } ____cacheline_aligned irq_desc_t;
  84
  85 extern irq_desc_t irq_desc [NR_IRQS];
  86
  87 /* Return a pointer to the irq descriptor for IRQ.  */
  88 static inline irq_desc_t *
  89 irq_descp (int irq)
  90 {
  91         return irq_desc + irq;
  92 }
  93
  94 #include <asm/hw_irq.h> /* the arch dependent stuff */
  95
  96 extern int setup_irq(unsigned int irq, struct irqaction * new);
  97
  98 #ifdef CONFIG_GENERIC_HARDIRQS
  99 extern cpumask_t irq_affinity[NR_IRQS];
 100
 101 #ifdef CONFIG_SMP
 102 static inline void set_native_irq_info(int irq, cpumask_t mask)
 103 {
 104         irq_affinity[irq] = mask;
 105 }
 106 #else
 107 static inline void set_native_irq_info(int irq, cpumask_t mask)
 108 {
 109 }
 110 #endif
 111
 112 #ifdef CONFIG_SMP
 113
 114 #if defined (CONFIG_GENERIC_PENDING_IRQ) || defined (CONFIG_IRQBALANCE)
 115 extern cpumask_t pending_irq_cpumask[NR_IRQS];
 116
 117 static inline void set_pending_irq(unsigned int irq, cpumask_t mask)
 118 {
 119         irq_desc_t *desc = irq_desc + irq;
 120         unsigned long flags;
 121
 122         spin_lock_irqsave(&desc->lock, flags);
 123         desc->move_irq = 1;
 124         pending_irq_cpumask[irq] = mask;
 125         spin_unlock_irqrestore(&desc->lock, flags);
 126 }
 127
 128 static inline void
 129 move_native_irq(int irq)
 130 {
 131         cpumask_t tmp;
 132         irq_desc_t *desc = irq_descp(irq);
 133
 134         if (likely (!desc->move_irq))
 135                 return;
 136
 137         desc->move_irq = 0;
 138
 139         if (likely(cpus_empty(pending_irq_cpumask[irq])))
 140                 return;
 141
 142         if (!desc->handler->set_affinity)
 143                 return;
 144
 145         /* note - we hold the desc->lock */
 146         cpus_and(tmp, pending_irq_cpumask[irq], cpu_online_map);
 147
 148         /*
 149          * If there was a valid mask to work with, please
 150          * do the disable, re-program, enable sequence.
 151          * This is *not* particularly important for level triggered
 152          * but in a edge trigger case, we might be setting rte
 153          * when an active trigger is comming in. This could
 154          * cause some ioapics to mal-function.
 155          * Being paranoid i guess!
 156          */
 157         if (unlikely(!cpus_empty(tmp))) {
 158                 desc->handler->disable(irq);
 159                 desc->handler->set_affinity(irq,tmp);
 160                 desc->handler->enable(irq);
 161         }
 162         cpus_clear(pending_irq_cpumask[irq]);
 163 }
 164
 165 #ifdef CONFIG_PCI_MSI
 166 /*
 167  * Wonder why these are dummies?
 168  * For e.g the set_ioapic_affinity_vector() calls the set_ioapic_affinity_irq()
 169  * counter part after translating the vector to irq info. We need to perform
 170  * this operation on the real irq, when we dont use vector, i.e when
 171  * pci_use_vector() is false.
 172  */
 173 static inline void move_irq(int irq)
 174 {
 175 }
 176
 177 static inline void set_irq_info(int irq, cpumask_t mask)
 178 {
 179 }
 180
 181 #else // CONFIG_PCI_MSI
 182
 183 static inline void move_irq(int irq)
 184 {
 185         move_native_irq(irq);
 186 }
 187
 188 static inline void set_irq_info(int irq, cpumask_t mask)
 189 {
 190         set_native_irq_info(irq, mask);
 191 }
 192 #endif // CONFIG_PCI_MSI
 193
 194 #else   // CONFIG_GENERIC_PENDING_IRQ || CONFIG_IRQBALANCE
 195
 196 #define move_irq(x)
 197 #define move_native_irq(x)
 198 #define set_pending_irq(x,y)
 199 static inline void set_irq_info(int irq, cpumask_t mask)
 200 {
 201         set_native_irq_info(irq, mask);
 202 }
 203
 204 #endif // CONFIG_GENERIC_PENDING_IRQ
 205
 206 #else // CONFIG_SMP
 207
 208 #define move_irq(x)
 209 #define move_native_irq(x)
 210
 211 #endif // CONFIG_SMP
 212
 213 extern int no_irq_affinity;
 214 extern int noirqdebug_setup(char *str);
 215
 216 extern fastcall int handle_IRQ_event(unsigned int irq, struct pt_regs *regs,
 217                                         struct irqaction *action);
 218 extern fastcall unsigned int __do_IRQ(unsigned int irq, struct pt_regs *regs);
 219 extern void note_interrupt(unsigned int irq, irq_desc_t *desc,
 220                                         int action_ret, struct pt_regs *regs);
 221 extern int can_request_irq(unsigned int irq, unsigned long irqflags);
 222
 223 extern void init_irq_proc(void);
 224 #endif
 225
 226 extern hw_irq_controller no_irq_type;  /* needed in every arch ? */
 227
 228 #endif
 229
 230 #endif /* __irq_h */