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author | fishsoupisgood <github@madingley.org> | 2019-04-29 01:17:54 +0100 |
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committer | fishsoupisgood <github@madingley.org> | 2019-05-27 03:43:43 +0100 |
commit | 3f2546b2ef55b661fd8dd69682b38992225e86f6 (patch) | |
tree | 65ca85f13617aee1dce474596800950f266a456c /roms/ipxe/src/arch/i386/include/pic8259.h | |
download | qemu-master.tar.gz qemu-master.tar.bz2 qemu-master.zip |
Diffstat (limited to 'roms/ipxe/src/arch/i386/include/pic8259.h')
-rw-r--r-- | roms/ipxe/src/arch/i386/include/pic8259.h | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/roms/ipxe/src/arch/i386/include/pic8259.h b/roms/ipxe/src/arch/i386/include/pic8259.h new file mode 100644 index 00000000..a07e97d3 --- /dev/null +++ b/roms/ipxe/src/arch/i386/include/pic8259.h @@ -0,0 +1,73 @@ +/* + * Basic support for controlling the 8259 Programmable Interrupt Controllers. + * + * Initially written by Michael Brown (mcb30). + */ + +FILE_LICENCE ( GPL2_OR_LATER ); + +#ifndef PIC8259_H +#define PIC8259_H + +#include <ipxe/io.h> + +/* For segoff_t */ +#include "realmode.h" + +#define IRQ_PIC_CUTOFF 8 + +/* 8259 register locations */ +#define PIC1_ICW1 0x20 +#define PIC1_OCW2 0x20 +#define PIC1_OCW3 0x20 +#define PIC1_ICR 0x20 +#define PIC1_IRR 0x20 +#define PIC1_ISR 0x20 +#define PIC1_ICW2 0x21 +#define PIC1_ICW3 0x21 +#define PIC1_ICW4 0x21 +#define PIC1_IMR 0x21 +#define PIC2_ICW1 0xa0 +#define PIC2_OCW2 0xa0 +#define PIC2_OCW3 0xa0 +#define PIC2_ICR 0xa0 +#define PIC2_IRR 0xa0 +#define PIC2_ISR 0xa0 +#define PIC2_ICW2 0xa1 +#define PIC2_ICW3 0xa1 +#define PIC2_ICW4 0xa1 +#define PIC2_IMR 0xa1 + +/* Register command values */ +#define OCW3_ID 0x08 +#define OCW3_READ_IRR 0x03 +#define OCW3_READ_ISR 0x02 +#define ICR_EOI_NON_SPECIFIC 0x20 +#define ICR_EOI_NOP 0x40 +#define ICR_EOI_SPECIFIC 0x60 +#define ICR_EOI_SET_PRIORITY 0xc0 + +/* Macros to enable/disable IRQs */ +#define IMR_REG(x) ( (x) < IRQ_PIC_CUTOFF ? PIC1_IMR : PIC2_IMR ) +#define IMR_BIT(x) ( 1 << ( (x) % IRQ_PIC_CUTOFF ) ) +#define irq_enabled(x) ( ( inb ( IMR_REG(x) ) & IMR_BIT(x) ) == 0 ) +#define enable_irq(x) outb ( inb( IMR_REG(x) ) & ~IMR_BIT(x), IMR_REG(x) ) +#define disable_irq(x) outb ( inb( IMR_REG(x) ) | IMR_BIT(x), IMR_REG(x) ) + +/* Macros for acknowledging IRQs */ +#define ICR_REG( irq ) ( (irq) < IRQ_PIC_CUTOFF ? PIC1_ICR : PIC2_ICR ) +#define ICR_VALUE( irq ) ( (irq) % IRQ_PIC_CUTOFF ) +#define CHAINED_IRQ 2 + +/* Utility macros to convert IRQ numbers to INT numbers and INT vectors */ +#define IRQ_INT( irq ) ( ( ( (irq) - IRQ_PIC_CUTOFF ) ^ 0x70 ) & 0x7f ) + +/* Other constants */ +#define IRQ_MAX 15 +#define IRQ_NONE -1U + +/* Function prototypes + */ +void send_eoi ( unsigned int irq ); + +#endif /* PIC8259_H */ |