blob: 22370b9cecc41c6b67c8279332958ebf06c09df4 [file] [log] [blame]
/*
* -----------------------------------------------------------------------
*
* Copyright 2009 Intel Corporation; author: H. Peter Anvin
*
* This program 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, Inc., 53 Temple Place Ste 330,
* Boston MA 02111-1307, USA; either version 2 of the License, or
* (at your option) any later version; incorporated herein by reference.
*
* -----------------------------------------------------------------------
*
* serirq.c
*
* Serial port IRQ code
*
* We don't know what IRQ, if any, we have, so map all of them...
*/
#include <sys/io.h>
#include <string.h>
#include <fs.h>
#include "bios.h"
static char serial_buf[serial_buf_size];
static unsigned short SerialIRQPort; /* Serial port w IRQ service */
char *SerialHead = serial_buf; /* Head of serial port rx buffer */
char *SerialTail = serial_buf; /* Tail of serial port rx buffer */
static unsigned char IRQMask[2]; /* PIC IRQ mask status */
static unsigned int oldirq[16];
typedef void (*irqhandler_t)(void);
void sirq_cleanup(void);
static void irq_common(unsigned short old_irq)
{
char *dst;
irqhandler_t next;
char val;
dst = SerialHead;
next = (irqhandler_t)oldirq[old_irq];
/* LSR */
val = inb(SerialPort + 5);
/* Received data */
while (val & 1) {
/* RDR */
*dst++ = inb(SerialPort);
/* LSR */
val = inb(SerialPort + 5);
if ((val & FlowIgnore) == FlowIgnore) {
/* Wrap around if necessary */
dst = (char *)((unsigned long)dst & (serial_buf_size - 1));
/* Would this cause overflow? */
if (dst != SerialTail)
SerialHead = dst;
}
}
/* Chain to next handler */
next();
}
#define SERIAL_IRQ_HANDLER(n) \
static void serstub_irq##n(void) \
{ \
irq_common(n); \
}
SERIAL_IRQ_HANDLER(0);
SERIAL_IRQ_HANDLER(1);
SERIAL_IRQ_HANDLER(2);
SERIAL_IRQ_HANDLER(3);
SERIAL_IRQ_HANDLER(4);
SERIAL_IRQ_HANDLER(5);
SERIAL_IRQ_HANDLER(6);
SERIAL_IRQ_HANDLER(7);
SERIAL_IRQ_HANDLER(8);
SERIAL_IRQ_HANDLER(9);
SERIAL_IRQ_HANDLER(10);
SERIAL_IRQ_HANDLER(11);
SERIAL_IRQ_HANDLER(12);
SERIAL_IRQ_HANDLER(13);
SERIAL_IRQ_HANDLER(14);
SERIAL_IRQ_HANDLER(15);
static inline void save_irq_vectors(uint32_t *src, uint32_t *dst)
{
int i;
for (i = 0; i < 8; i++)
*dst++ = *src++;
}
static inline void install_irq_vectors(uint32_t *dst, int first)
{
if (first) {
*dst++ = (uint32_t)serstub_irq0;
*dst++ = (uint32_t)serstub_irq1;
*dst++ = (uint32_t)serstub_irq2;
*dst++ = (uint32_t)serstub_irq3;
*dst++ = (uint32_t)serstub_irq4;
*dst++ = (uint32_t)serstub_irq5;
*dst++ = (uint32_t)serstub_irq6;
*dst++ = (uint32_t)serstub_irq7;
} else {
*dst++ = (uint32_t)serstub_irq8;
*dst++ = (uint32_t)serstub_irq9;
*dst++ = (uint32_t)serstub_irq10;
*dst++ = (uint32_t)serstub_irq11;
*dst++ = (uint32_t)serstub_irq12;
*dst++ = (uint32_t)serstub_irq13;
*dst++ = (uint32_t)serstub_irq14;
*dst++ = (uint32_t)serstub_irq15;
}
}
__export void sirq_install(void)
{
char val, val2;
sirq_cleanup();
save_irq_vectors((uint32_t *)(4 * 0x8), oldirq);
save_irq_vectors((uint32_t *)(4 * 0x70), &oldirq[8]);
install_irq_vectors((uint32_t *)(4 * 0x8), 1);
install_irq_vectors((uint32_t *)(4 * 0x70), 0);
SerialIRQPort = SerialPort;
/* Clear DLAB (should already be...) */
outb(0x3, SerialIRQPort + 5);
io_delay();
/* Enable receive interrupt */
outb(0x1, SerialIRQPort + 1);
io_delay();
/*
* Enable all the interrupt lines at the PIC. Some BIOSes only
* enable the timer interrupts and other interrupts actively
* in use by the BIOS.
*/
/* Secondary PIC mask register */
val = inb(0xA1);
val2 = inb(0x21);
IRQMask[0] = val;
IRQMask[1] = val2;
io_delay();
/* Remove all interrupt masks */
outb(0x21, 0);
outb(0xA1, 0);
}
__export void sirq_cleanup_nowipe(void)
{
uint32_t *dst;
int i;
if (!SerialIRQPort)
return;
/* Clear DLAB */
outb(0x3, SerialIRQPort + 5);
io_delay();
/* Clear IER */
outb(0x0, SerialIRQPort + 1);
io_delay();
/* Restore PIC masks */
outb(IRQMask[0], 0x21);
outb(IRQMask[1], 0xA1);
/* Restore the original interrupt vectors */
dst = (uint32_t *)(4 * 0x8);
for (i = 0; i < 8; i++)
*dst++ = oldirq[i];
dst = (uint32_t *)(4 * 0x70);
for (i = 8; i < 16; i++)
*dst++ = oldirq[i];
/* No active interrupt system */
SerialIRQPort = 0;
}
void sirq_cleanup(void)
{
sirq_cleanup_nowipe();
memset(SerialHead, 0x0, serial_buf_size);
}