xref: /openbmc/linux/arch/x86/include/asm/i8259.h (revision 30c7e5b123673d5e570e238dbada2fb68a87212c)
1b2441318SGreg Kroah-Hartman /* SPDX-License-Identifier: GPL-2.0 */
21965aae3SH. Peter Anvin #ifndef _ASM_X86_I8259_H
31965aae3SH. Peter Anvin #define _ASM_X86_I8259_H
4bb898558SAl Viro 
5bb898558SAl Viro #include <linux/delay.h>
6bb898558SAl Viro 
7bb898558SAl Viro extern unsigned int cached_irq_mask;
8bb898558SAl Viro 
9bb898558SAl Viro #define __byte(x, y)		(((unsigned char *)&(y))[x])
10bb898558SAl Viro #define cached_master_mask	(__byte(0, cached_irq_mask))
11bb898558SAl Viro #define cached_slave_mask	(__byte(1, cached_irq_mask))
12bb898558SAl Viro 
13bb898558SAl Viro /* i8259A PIC registers */
14bb898558SAl Viro #define PIC_MASTER_CMD		0x20
15bb898558SAl Viro #define PIC_MASTER_IMR		0x21
16bb898558SAl Viro #define PIC_MASTER_ISR		PIC_MASTER_CMD
17bb898558SAl Viro #define PIC_MASTER_POLL		PIC_MASTER_ISR
18bb898558SAl Viro #define PIC_MASTER_OCW3		PIC_MASTER_ISR
19bb898558SAl Viro #define PIC_SLAVE_CMD		0xa0
20bb898558SAl Viro #define PIC_SLAVE_IMR		0xa1
21bb898558SAl Viro 
22bb898558SAl Viro /* i8259A PIC related value */
23bb898558SAl Viro #define PIC_CASCADE_IR		2
24bb898558SAl Viro #define MASTER_ICW4_DEFAULT	0x01
25bb898558SAl Viro #define SLAVE_ICW4_DEFAULT	0x01
26bb898558SAl Viro #define PIC_ICW4_AEOI		2
27bb898558SAl Viro 
285619c280SThomas Gleixner extern raw_spinlock_t i8259A_lock;
29bb898558SAl Viro 
30bb898558SAl Viro /* the PIC may need a careful delay on some platforms, hence specific calls */
31bb898558SAl Viro static inline unsigned char inb_pic(unsigned int port)
32bb898558SAl Viro {
33bb898558SAl Viro 	unsigned char value = inb(port);
34bb898558SAl Viro 
35bb898558SAl Viro 	/*
36bb898558SAl Viro 	 * delay for some accesses to PIC on motherboard or in chipset
37bb898558SAl Viro 	 * must be at least one microsecond, so be safe here:
38bb898558SAl Viro 	 */
39bb898558SAl Viro 	udelay(2);
40bb898558SAl Viro 
41bb898558SAl Viro 	return value;
42bb898558SAl Viro }
43bb898558SAl Viro 
44bb898558SAl Viro static inline void outb_pic(unsigned char value, unsigned int port)
45bb898558SAl Viro {
46bb898558SAl Viro 	outb(value, port);
47bb898558SAl Viro 	/*
48bb898558SAl Viro 	 * delay for some accesses to PIC on motherboard or in chipset
49bb898558SAl Viro 	 * must be at least one microsecond, so be safe here:
50bb898558SAl Viro 	 */
51bb898558SAl Viro 	udelay(2);
52bb898558SAl Viro }
53bb898558SAl Viro 
54bb898558SAl Viro extern struct irq_chip i8259A_chip;
55bb898558SAl Viro 
56ef354866SJacob Pan struct legacy_pic {
57ef354866SJacob Pan 	int nr_legacy_irqs;
58ef354866SJacob Pan 	struct irq_chip *chip;
594305df94SThomas Gleixner 	void (*mask)(unsigned int irq);
604305df94SThomas Gleixner 	void (*unmask)(unsigned int irq);
61ef354866SJacob Pan 	void (*mask_all)(void);
62ef354866SJacob Pan 	void (*restore_mask)(void);
63ef354866SJacob Pan 	void (*init)(int auto_eoi);
648c058b0bSVitaly Kuznetsov 	int (*probe)(void);
65ef354866SJacob Pan 	int (*irq_pending)(unsigned int irq);
66ef354866SJacob Pan 	void (*make_irq)(unsigned int irq);
67ef354866SJacob Pan };
68ef354866SJacob Pan 
69ef354866SJacob Pan extern struct legacy_pic *legacy_pic;
70ef354866SJacob Pan extern struct legacy_pic null_legacy_pic;
71ef354866SJacob Pan 
72*30c7e5b1SPeter Zijlstra static inline bool has_legacy_pic(void)
73*30c7e5b1SPeter Zijlstra {
74*30c7e5b1SPeter Zijlstra 	return legacy_pic != &null_legacy_pic;
75*30c7e5b1SPeter Zijlstra }
76*30c7e5b1SPeter Zijlstra 
7795d76accSJiang Liu static inline int nr_legacy_irqs(void)
7895d76accSJiang Liu {
7995d76accSJiang Liu 	return legacy_pic->nr_legacy_irqs;
8095d76accSJiang Liu }
8195d76accSJiang Liu 
821965aae3SH. Peter Anvin #endif /* _ASM_X86_I8259_H */
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