Line data    Source code

       1             : /* SPDX-License-Identifier: GPL-2.0 */
       2             : #ifndef _ASM_X86_I8259_H
       3             : #define _ASM_X86_I8259_H
       4             : 
       5             : #include <linux/delay.h>
       6             : #include <asm/io.h>
       7             : 
       8             : extern unsigned int cached_irq_mask;
       9             : 
      10             : #define __byte(x, y)            (((unsigned char *)&(y))[x])
      11             : #define cached_master_mask      (__byte(0, cached_irq_mask))
      12             : #define cached_slave_mask       (__byte(1, cached_irq_mask))
      13             : 
      14             : /* i8259A PIC registers */
      15             : #define PIC_MASTER_CMD          0x20
      16             : #define PIC_MASTER_IMR          0x21
      17             : #define PIC_MASTER_ISR          PIC_MASTER_CMD
      18             : #define PIC_MASTER_POLL         PIC_MASTER_ISR
      19             : #define PIC_MASTER_OCW3         PIC_MASTER_ISR
      20             : #define PIC_SLAVE_CMD           0xa0
      21             : #define PIC_SLAVE_IMR           0xa1
      22             : 
      23             : /* i8259A PIC related value */
      24             : #define PIC_CASCADE_IR          2
      25             : #define MASTER_ICW4_DEFAULT     0x01
      26             : #define SLAVE_ICW4_DEFAULT      0x01
      27             : #define PIC_ICW4_AEOI           2
      28             : 
      29             : extern raw_spinlock_t i8259A_lock;
      30             : 
      31             : /* the PIC may need a careful delay on some platforms, hence specific calls */
      32             : static inline unsigned char inb_pic(unsigned int port)
      33             : {
      34             :         unsigned char value = inb(port);
      35             : 
      36             :         /*
      37             :          * delay for some accesses to PIC on motherboard or in chipset
      38             :          * must be at least one microsecond, so be safe here:
      39             :          */
      40             :         udelay(2);
      41             : 
      42             :         return value;
      43             : }
      44             : 
      45           8 : static inline void outb_pic(unsigned char value, unsigned int port)
      46             : {
      47           8 :         outb(value, port);
      48             :         /*
      49             :          * delay for some accesses to PIC on motherboard or in chipset
      50             :          * must be at least one microsecond, so be safe here:
      51             :          */
      52           8 :         udelay(2);
      53           1 : }
      54             : 
      55             : extern struct irq_chip i8259A_chip;
      56             : 
      57             : struct legacy_pic {
      58             :         int nr_legacy_irqs;
      59             :         struct irq_chip *chip;
      60             :         void (*mask)(unsigned int irq);
      61             :         void (*unmask)(unsigned int irq);
      62             :         void (*mask_all)(void);
      63             :         void (*restore_mask)(void);
      64             :         void (*init)(int auto_eoi);
      65             :         int (*probe)(void);
      66             :         int (*irq_pending)(unsigned int irq);
      67             :         void (*make_irq)(unsigned int irq);
      68             : };
      69             : 
      70             : extern struct legacy_pic *legacy_pic;
      71             : extern struct legacy_pic null_legacy_pic;
      72             : 
      73           0 : static inline bool has_legacy_pic(void)
      74             : {
      75           0 :         return legacy_pic != &null_legacy_pic;
      76             : }
      77             : 
      78         716 : static inline int nr_legacy_irqs(void)
      79             : {
      80         716 :         return legacy_pic->nr_legacy_irqs;
      81             : }
      82             : 
      83             : #endif /* _ASM_X86_I8259_H */