zephyr/drivers/interrupt_controller/i8259.c

66 lines
1.8 KiB
C

/*
* Copyright (c) 2010-2015 Wind River Systems, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* @file
* @brief Disable Intel 8259A PIC (Programmable Interrupt Controller)
*
* This module disables the Intel 8259A PIC (Programmable Interrupt Controller)
* to prevent it from generating spurious interrupts.
*/
#include <nanokernel.h>
#include <arch/cpu.h>
#include <toolchain.h>
#include <sections.h>
#include <device.h>
#include <init.h>
#include <board.h>
/* programmable interrupt controller info (pair of cascaded 8259A devices) */
#define PIC_MASTER_BASE_ADRS 0x20
#define PIC_SLAVE_BASE_ADRS 0xa0
#define PIC_REG_ADDR_INTERVAL 1
/* register definitions */
#define PIC_ADRS(baseAdrs, reg) (baseAdrs + (reg * PIC_REG_ADDR_INTERVAL))
#define PIC_PORT2(base) PIC_ADRS(base, 0x01) /* port 2 */
#define PIC_DISABLE 0xff /* Disable PIC command */
/**
*
* @brief Initialize the Intel 8259A PIC device driver
*
* This routine disables the 8259A PIC device to prevent it from
* generating spurious interrupts.
*
* @return N/A
*/
int _i8259_init(struct device *unused)
{
ARG_UNUSED(unused);
sys_out8(PIC_DISABLE, PIC_PORT2(PIC_SLAVE_BASE_ADRS));
sys_out8(PIC_DISABLE, PIC_PORT2(PIC_MASTER_BASE_ADRS));
return 0;
}
SYS_INIT(_i8259_init, PRE_KERNEL_1, CONFIG_KERNEL_INIT_PRIORITY_DEFAULT);