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