sortix-mirror/kernel/x86-family/pic.cpp

119 lines
3.7 KiB
C++

/*
* Copyright (c) 2011, 2012, 2013, 2014 Jonas 'Sortie' Termansen.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
* x86-family/pic.cpp
* Driver for the Programmable Interrupt Controller.
*/
#include <stdint.h>
#include <sortix/kernel/cpu.h>
#include <sortix/kernel/interrupt.h>
#include <sortix/kernel/ioport.h>
#include <sortix/kernel/kernel.h>
#include "pic.h"
namespace Sortix {
namespace PIC {
const uint16_t PIC_MASTER = 0x20;
const uint16_t PIC_SLAVE = 0xA0;
const uint16_t PIC_COMMAND = 0x00;
const uint16_t PIC_DATA = 0x01;
const uint8_t PIC_CMD_ENDINTR = 0x20;
const uint8_t PIC_ICW1_ICW4 = 0x01; // ICW4 (not) needed
const uint8_t PIC_ICW1_SINGLE = 0x02; // Single (cascade) mode
const uint8_t PIC_ICW1_INTERVAL4 = 0x04; // Call address interval 4 (8)
const uint8_t PIC_ICW1_LEVEL = 0x08; // Level triggered (edge) mode
const uint8_t PIC_CMD_INIT = 0x10;
const uint8_t PIC_MODE_8086 = 0x01; // 8086/88 (MCS-80/85) mode
const uint8_t PIC_MODE_AUTO = 0x02; // Auto (normal) EOI
const uint8_t PIC_MODE_BUF_SLAVE = 0x08; // Buffered mode/slave
const uint8_t PIC_MODE_BUF_MASTER = 0x0C; // Buffered mode/master
const uint8_t PIC_MODE_SFNM = 0x10; // Special fully nested (not)
const uint8_t PIC_READ_IRR = 0x0A;
const uint8_t PIC_READ_ISR = 0x0B;
static uint16_t ReadRegister(uint8_t ocw3)
{
outport8(PIC_MASTER + PIC_COMMAND, ocw3);
outport8(PIC_SLAVE + PIC_COMMAND, ocw3);
return inport8(PIC_MASTER + PIC_COMMAND) << 0 |
inport8(PIC_SLAVE + PIC_COMMAND) << 8;
}
uint16_t ReadIRR()
{
return ReadRegister(PIC_READ_IRR);
}
uint16_t ReadISR()
{
return ReadRegister(PIC_READ_ISR);
}
extern "C" void ReprogramPIC()
{
uint8_t master_mask = 0;
uint8_t slave_mask = 0;
outport8(PIC_MASTER + PIC_COMMAND, PIC_CMD_INIT | PIC_ICW1_ICW4);
outport8(PIC_SLAVE + PIC_COMMAND, PIC_CMD_INIT | PIC_ICW1_ICW4);
outport8(PIC_MASTER + PIC_DATA, Interrupt::IRQ0);
outport8(PIC_SLAVE + PIC_DATA, Interrupt::IRQ8);
outport8(PIC_MASTER + PIC_DATA, 0x04); // Slave PIC at IRQ2
outport8(PIC_SLAVE + PIC_DATA, 0x02); // Cascade Identity
outport8(PIC_MASTER + PIC_DATA, PIC_MODE_8086);
outport8(PIC_SLAVE + PIC_DATA, PIC_MODE_8086);
outport8(PIC_MASTER + PIC_DATA, master_mask);
outport8(PIC_SLAVE + PIC_DATA, slave_mask);
}
extern "C" void DeprogramPIC()
{
uint8_t master_mask = 0;
uint8_t slave_mask = 0;
outport8(PIC_MASTER + PIC_COMMAND, PIC_CMD_INIT | PIC_ICW1_ICW4);
outport8(PIC_SLAVE + PIC_COMMAND, PIC_CMD_INIT | PIC_ICW1_ICW4);
outport8(PIC_MASTER + PIC_DATA, 0x08);
outport8(PIC_SLAVE + PIC_DATA, 0x70);
outport8(PIC_MASTER + PIC_DATA, 0x04); // Slave PIC at IRQ2
outport8(PIC_SLAVE + PIC_DATA, 0x02); // Cascade Identity
outport8(PIC_MASTER + PIC_DATA, PIC_MODE_8086);
outport8(PIC_SLAVE + PIC_DATA, PIC_MODE_8086);
outport8(PIC_MASTER + PIC_DATA, master_mask);
outport8(PIC_SLAVE + PIC_DATA, slave_mask);
}
void SendMasterEOI()
{
outport8(PIC_MASTER, PIC_CMD_ENDINTR);
}
void SendSlaveEOI()
{
outport8(PIC_SLAVE, PIC_CMD_ENDINTR);
}
void SendEOI(unsigned int irq)
{
if ( 8 <= irq )
SendSlaveEOI();
SendMasterEOI();
}
} // namespace PIC
} // namespace Sortix