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  #define PIC_ELCR1		0x4d0
23  #define PIC_ELCR2		0x4d1
24  
25  /* i8259A PIC related value */
26  #define PIC_CASCADE_IR		2
27  #define MASTER_ICW4_DEFAULT	0x01
28  #define SLAVE_ICW4_DEFAULT	0x01
29  #define PIC_ICW4_AEOI		2
30  
31  extern raw_spinlock_t i8259A_lock;
32  
33  /* the PIC may need a careful delay on some platforms, hence specific calls */
inb_pic(unsigned int port)34  static inline unsigned char inb_pic(unsigned int port)
35  {
36  	unsigned char value = inb(port);
37  
38  	/*
39  	 * delay for some accesses to PIC on motherboard or in chipset
40  	 * must be at least one microsecond, so be safe here:
41  	 */
42  	udelay(2);
43  
44  	return value;
45  }
46  
outb_pic(unsigned char value,unsigned int port)47  static inline void outb_pic(unsigned char value, unsigned int port)
48  {
49  	outb(value, port);
50  	/*
51  	 * delay for some accesses to PIC on motherboard or in chipset
52  	 * must be at least one microsecond, so be safe here:
53  	 */
54  	udelay(2);
55  }
56  
57  extern struct irq_chip i8259A_chip;
58  
59  struct legacy_pic {
60  	int nr_legacy_irqs;
61  	struct irq_chip *chip;
62  	void (*mask)(unsigned int irq);
63  	void (*unmask)(unsigned int irq);
64  	void (*mask_all)(void);
65  	void (*restore_mask)(void);
66  	void (*init)(int auto_eoi);
67  	int (*probe)(void);
68  	int (*irq_pending)(unsigned int irq);
69  	void (*make_irq)(unsigned int irq);
70  };
71  
72  void legacy_pic_pcat_compat(void);
73  
74  extern struct legacy_pic *legacy_pic;
75  extern struct legacy_pic null_legacy_pic;
76  
has_legacy_pic(void)77  static inline bool has_legacy_pic(void)
78  {
79  	return legacy_pic != &null_legacy_pic;
80  }
81  
nr_legacy_irqs(void)82  static inline int nr_legacy_irqs(void)
83  {
84  	return legacy_pic->nr_legacy_irqs;
85  }
86  
87  #endif /* _ASM_X86_I8259_H */
88