30 lines
839 B
C
30 lines
839 B
C
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#include <kernel/pic.h>
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void PIC_remap() {
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unsigned char a1, a2;
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a1 = inb(PIC1_DATA); // save masks
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a2 = inb(PIC2_DATA);
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outb(PIC1_COMMAND, ICW1_INIT | ICW1_ICW4); // Start init sequence in cascade mode
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io_wait();
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outb(PIC2_COMMAND, ICW1_INIT | ICW1_ICW4);
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io_wait();
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outb(PIC1_DATA, PIC1_OFFSET); // ICW2: Master PIC vector offset
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io_wait();
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outb(PIC2_DATA, PIC2_OFFSET); // ICW2: Slave PIC vector offset
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io_wait();
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outb(PIC1_DATA, 4); // ICW3: tell Master PIC that theres a slave PIC at IRQ2 (0000 0100)
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io_wait();
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outb(PIC2_DATA, 2); // ICW3: tell Slave PIC its cascade identity (0000 0010)
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io_wait();
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outb(PIC1_DATA, ICW4_8086);
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io_wait();
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outb(PIC2_DATA, ICW4_8086);
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io_wait();
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outb(PIC1_DATA, a1); // restore saved masks
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outb(PIC2_DATA, a2);
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}
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