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/*
RCC-Project
Copyright (C) 2026 Richard Qin
This file is part of RCC-Project.
RCC-Project is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3 of the License, or (at your option) any
later version.
RCC-Project is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with
RCC-Project; see the file COPYING. If not see
<http://www.gnu.org/licenses/>.
*/
#include "bios.h"
#include "io.h"
#define PIC1_COMMAND 0x0020u
#define PIC1_DATA 0x0021u
#define PIC2_COMMAND 0x00A0u
#define PIC2_DATA 0x00A1u
#define PIC_ICW1_INIT 0x11u
#define PIC_ICW4_8086 0x01u
#define PIC1_VECTOR_BASE 0x08u
#define PIC2_VECTOR_BASE 0x70u
#define PIC1_CASCADE_ID 0x04u
#define PIC2_CASCADE_ID 0x02u
#define PIC1_MASK_DEFAULT 0xF8u
#define PIC2_MASK_DEFAULT 0xFFu
void
pic_init (void)
{
io_out8 (PIC1_COMMAND, PIC_ICW1_INIT);
io_out8 (PIC2_COMMAND, PIC_ICW1_INIT);
io_out8 (PIC1_DATA, PIC1_VECTOR_BASE);
io_out8 (PIC2_DATA, PIC2_VECTOR_BASE);
io_out8 (PIC1_DATA, PIC1_CASCADE_ID);
io_out8 (PIC2_DATA, PIC2_CASCADE_ID);
io_out8 (PIC1_DATA, PIC_ICW4_8086);
io_out8 (PIC2_DATA, PIC_ICW4_8086);
/*
* Keep the timer, keyboard, and cascade lines enabled.
* All other master IRQ lines remain masked.
*/
io_out8 (PIC1_DATA, PIC1_MASK_DEFAULT);
io_out8 (PIC2_DATA, PIC2_MASK_DEFAULT);
}
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