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 7 extern unsigned int cached_irq_mask; 8 9 #define __byte(x, y) (((unsigned char *)&(y))[x]) 10 #define cached_master_mask (__byte(0, cached_irq_mask)) 11 #define cached_slave_mask (__byte(1, cached_irq_mask)) 12 13 /* i8259A PIC registers */ 14 #define PIC_MASTER_CMD 0x20 15 #define PIC_MASTER_IMR 0x21 16 #define PIC_MASTER_ISR PIC_MASTER_CMD 17 #define PIC_MASTER_POLL PIC_MASTER_ISR 18 #define PIC_MASTER_OCW3 PIC_MASTER_ISR 19 #define PIC_SLAVE_CMD 0xa0 20 #define PIC_SLAVE_IMR 0xa1 21 22 /* i8259A PIC related value */ 23 #define PIC_CASCADE_IR 2 24 #define MASTER_ICW4_DEFAULT 0x01 25 #define SLAVE_ICW4_DEFAULT 0x01 26 #define PIC_ICW4_AEOI 2 27 28 extern raw_spinlock_t i8259A_lock; 29 30 /* the PIC may need a careful delay on some platforms, hence specific calls */ 31 static inline unsigned char inb_pic(unsigned int port) 32 { 33 unsigned char value = inb(port); 34 35 /* 36 * delay for some accesses to PIC on motherboard or in chipset 37 * must be at least one microsecond, so be safe here: 38 */ 39 udelay(2); 40 41 return value; 42 } 43 44 static inline void outb_pic(unsigned char value, unsigned int port) 45 { 46 outb(value, port); 47 /* 48 * delay for some accesses to PIC on motherboard or in chipset 49 * must be at least one microsecond, so be safe here: 50 */ 51 udelay(2); 52 } 53 54 extern struct irq_chip i8259A_chip; 55 56 struct legacy_pic { 57 int nr_legacy_irqs; 58 struct irq_chip *chip; 59 void (*mask)(unsigned int irq); 60 void (*unmask)(unsigned int irq); 61 void (*mask_all)(void); 62 void (*restore_mask)(void); 63 void (*init)(int auto_eoi); 64 int (*probe)(void); 65 int (*irq_pending)(unsigned int irq); 66 void (*make_irq)(unsigned int irq); 67 }; 68 69 extern struct legacy_pic *legacy_pic; 70 extern struct legacy_pic null_legacy_pic; 71 72 static inline bool has_legacy_pic(void) 73 { 74 return legacy_pic != &null_legacy_pic; 75 } 76 77 static inline int nr_legacy_irqs(void) 78 { 79 return legacy_pic->nr_legacy_irqs; 80 } 81 82 #endif /* _ASM_X86_I8259_H */ 83