x86: Add pic_unmask_irq() helper

This patch implements the pic_unmask_irq() helper and uses it where
applicable. This function zeros the corresponding bit from the IRQ
number in IMR register.

This patch doesn't implement the pic_mask_irq() helper since it is not
useful at this moment.
This commit is contained in:
Andre Guedes 2015-07-02 17:46:47 -03:00 committed by Jesus Sanchez-Palencia
parent b8056b9c97
commit 826ff7cb29
5 changed files with 55 additions and 5 deletions

View file

@ -1,6 +1,6 @@
CONTIKI_CPU_DIRS = . drivers
CONTIKI_SOURCEFILES += mtarch.c gdt.c helpers.S idt.c cpu.c rtc.c pit.c
CONTIKI_SOURCEFILES += mtarch.c gdt.c helpers.S idt.c cpu.c rtc.c pit.c pic.c
### Compiler definitions
CC = gcc

48
cpu/x86/drivers/pic.c Normal file
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@ -0,0 +1,48 @@
/*
* Copyright (C) 2015, Intel Corporation. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* 3. Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "drivers/pic.h"
void
pic_unmask_irq(unsigned int num)
{
uint16_t port;
uint8_t bitmap;
if(num <= 7) {
port = PIC1_DATA_PORT;
} else {
port = PIC2_DATA_PORT;
num -= 8;
}
bitmap = inb(port);
outb(port, bitmap & ~BIT(num));
}

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@ -38,6 +38,8 @@
#define PIC2_CMD_PORT 0xA0
#define PIC2_DATA_PORT 0xA1
void pic_unmask_irq(unsigned int num);
/* This function initializes the daisy-chained Master and Slave 8259 PICs.
* It is only called once, so let's give the compiler the option to inline it.
* For more information about the ICWs, please refer to http://stanislavs.org/helppc/8259.html.

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@ -30,6 +30,7 @@
#include <math.h>
#include "drivers/pic.h"
#include "pit.h"
#include "helpers.h"
#include "interrupt.h"
@ -75,6 +76,5 @@ pit_init(uint32_t ticks_rate, pit_int_callback cb)
outb(PIT_COUNTER0_PORT, divisor & 0xFF); /* Write least significant bytes first. */
outb(PIT_COUNTER0_PORT, (divisor >> 8) & 0xFF);
/* FIXME: Unmask IRQ0 from Master PIC. Add a pic_set_mask() or similar and call it here. */
outb(0x21, 0xfa);
pic_unmask_irq(0);
}

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@ -29,6 +29,7 @@
*/
#include "drivers/rtc.h"
#include "drivers/pic.h"
#include "helpers.h"
#include "interrupt.h"
@ -87,6 +88,5 @@ rtc_init(rtc_frequency_t frequency, void (*callback)(void))
outb(RTC_INDEX_REGISTER, 0x0B);
outb(RTC_TARGET_REGISTER, reg_b | BIT(6));
/* Unmask IRQ8 */
outb(0xA1, 0xFE);
pic_unmask_irq(8);
}