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
8extern 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
29extern raw_spinlock_t i8259A_lock;
30
31/* the PIC may need a careful delay on some platforms, hence specific calls */
32static 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
45static inline void outb_pic(unsigned char value, unsigned int port)
46{
47 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 udelay(2);
53}
54
55extern struct irq_chip i8259A_chip;
56
57struct 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
70extern struct legacy_pic *legacy_pic;
71extern struct legacy_pic null_legacy_pic;
72
73static inline bool has_legacy_pic(void)
74{
75 return legacy_pic != &null_legacy_pic;
76}
77
78static inline int nr_legacy_irqs(void)
79{
80 return legacy_pic->nr_legacy_irqs;
81}
82
83#endif /* _ASM_X86_I8259_H */
84