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
70void legacy_pic_pcat_compat(void);
71
72extern struct legacy_pic *legacy_pic;
73extern struct legacy_pic null_legacy_pic;
74
75static inline bool has_legacy_pic(void)
76{
77	return legacy_pic != &null_legacy_pic;
78}
79
80static inline int nr_legacy_irqs(void)
81{
82	return legacy_pic->nr_legacy_irqs;
83}
84
85#endif /* _ASM_X86_I8259_H */
86