arch/x86/include/asm/i8259.h

   1 #ifndef _ASM_X86_I8259_H
   2 #define _ASM_X86_I8259_H
   3
   4 #include <linux/delay.h>
   5
   6 extern unsigned int cached_irq_mask;
   7
   8 #define __byte(x, y)            (((unsigned char *)&(y))[x])
   9 #define cached_master_mask      (__byte(0, cached_irq_mask))
  10 #define cached_slave_mask       (__byte(1, cached_irq_mask))
  11
  12 /* i8259A PIC registers */
  13 #define PIC_MASTER_CMD          0x20
  14 #define PIC_MASTER_IMR          0x21
  15 #define PIC_MASTER_ISR          PIC_MASTER_CMD
  16 #define PIC_MASTER_POLL         PIC_MASTER_ISR
  17 #define PIC_MASTER_OCW3         PIC_MASTER_ISR
  18 #define PIC_SLAVE_CMD           0xa0
  19 #define PIC_SLAVE_IMR           0xa1
  20
  21 /* i8259A PIC related value */
  22 #define PIC_CASCADE_IR          2
  23 #define MASTER_ICW4_DEFAULT     0x01
  24 #define SLAVE_ICW4_DEFAULT      0x01
  25 #define PIC_ICW4_AEOI           2
  26
  27 extern raw_spinlock_t i8259A_lock;
  28
  29 /* the PIC may need a careful delay on some platforms, hence specific calls */
  30 static inline unsigned char inb_pic(unsigned int port)
  31 {
  32         unsigned char value = inb(port);
  33
  34         /*
  35          * delay for some accesses to PIC on motherboard or in chipset
  36          * must be at least one microsecond, so be safe here:
  37          */
  38         udelay(2);
  39
  40         return value;
  41 }
  42
  43 static inline void outb_pic(unsigned char value, unsigned int port)
  44 {
  45         outb(value, port);
  46         /*
  47          * delay for some accesses to PIC on motherboard or in chipset
  48          * must be at least one microsecond, so be safe here:
  49          */
  50         udelay(2);
  51 }
  52
  53 extern struct irq_chip i8259A_chip;
  54
  55 struct legacy_pic {
  56         int nr_legacy_irqs;
  57         struct irq_chip *chip;
  58         void (*mask)(unsigned int irq);
  59         void (*unmask)(unsigned int irq);
  60         void (*mask_all)(void);
  61         void (*restore_mask)(void);
  62         void (*init)(int auto_eoi);
  63         int (*probe)(void);
  64         int (*irq_pending)(unsigned int irq);
  65         void (*make_irq)(unsigned int irq);
  66 };
  67
  68 extern struct legacy_pic *legacy_pic;
  69 extern struct legacy_pic null_legacy_pic;
  70
  71 static inline int nr_legacy_irqs(void)
  72 {
  73         return legacy_pic->nr_legacy_irqs;
  74 }
  75
  76 #endif /* _ASM_X86_I8259_H */