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 */ 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 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 77 static inline bool has_legacy_pic(void) 78 { 79 return legacy_pic != &null_legacy_pic; 80 } 81 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