/*
* Copyright (c) 2001-2004 Jakub Jermar
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - 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.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
/** @addtogroup genarch_drivers
* @{
*/
/**
* @file
* @brief EGA driver.
*/
#include <genarch/drivers/ega/ega.h>
#include <putchar.h>
#include <mm/page.h>
#include <mm/as.h>
#include <mm/slab.h>
#include <arch/mm/page.h>
#include <synch/spinlock.h>
#include <arch/types.h>
#include <arch/asm.h>
#include <memstr.h>
#include <console/chardev.h>
#include <console/console.h>
#include <sysinfo/sysinfo.h>
#include <ddi/ddi.h>
/*
* The EGA driver.
* Simple and short. Function for displaying characters and "scrolling".
*/
SPINLOCK_INITIALIZE(egalock);
static uint32_t ega_cursor;
static uint8_t *videoram;
static uint8_t *backbuf;
static ioport8_t *ega_base;
#define SPACE 0x20
#define STYLE 0x07
#define EMPTY_CHAR (STYLE << 8 | SPACE)
/*
* This function takes care of scrolling.
*/
static void ega_check_cursor(void)
{
if (ega_cursor < EGA_SCREEN)
return;
memmove((void *) videoram
, (void *) (videoram
+ EGA_COLS
* 2), (EGA_SCREEN - EGA_COLS) * 2);
memmove((void *) backbuf
, (void *) (backbuf
+ EGA_COLS
* 2), (EGA_SCREEN - EGA_COLS) * 2);
memsetw(videoram + (EGA_SCREEN - EGA_COLS) * 2, EGA_COLS, EMPTY_CHAR);
memsetw(backbuf + (EGA_SCREEN - EGA_COLS) * 2, EGA_COLS, EMPTY_CHAR);
ega_cursor = ega_cursor - EGA_COLS;
}
static void ega_show_cursor(void)
{
pio_write_8(ega_base + EGA_INDEX_REG, 0x0a);
uint8_t stat = pio_read_8(ega_base + EGA_DATA_REG);
pio_write_8(ega_base + EGA_INDEX_REG, 0x0a);
pio_write_8(ega_base + EGA_DATA_REG, stat & (~(1 << 5)));
}
static void ega_move_cursor(void)
{
pio_write_8(ega_base + EGA_INDEX_REG, 0x0e);
pio_write_8(ega_base + EGA_DATA_REG, (uint8_t) ((ega_cursor >> 8) & 0xff));
pio_write_8(ega_base + EGA_INDEX_REG, 0x0f);
pio_write_8(ega_base + EGA_DATA_REG, (uint8_t) (ega_cursor & 0xff));
}
static void ega_sync_cursor(void)
{
pio_write_8(ega_base + EGA_INDEX_REG, 0x0e);
uint8_t hi = pio_read_8(ega_base + EGA_DATA_REG);
pio_write_8(ega_base + EGA_INDEX_REG, 0x0f);
uint8_t lo = pio_read_8(ega_base + EGA_DATA_REG);
ega_cursor = (hi << 8) | lo;
if (ega_cursor >= EGA_SCREEN)
ega_cursor = 0;
if ((ega_cursor % EGA_COLS) != 0)
ega_cursor = (ega_cursor + EGA_COLS) - ega_cursor % EGA_COLS;
memsetw(videoram + ega_cursor * 2, EGA_SCREEN - ega_cursor, EMPTY_CHAR);
memsetw(backbuf + ega_cursor * 2, EGA_SCREEN - ega_cursor, EMPTY_CHAR);
ega_check_cursor();
ega_move_cursor();
ega_show_cursor();
}
static void ega_display_char(char ch, bool silent)
{
backbuf[ega_cursor * 2] = ch;
backbuf[ega_cursor * 2 + 1] = STYLE;
if (!silent) {
videoram[ega_cursor * 2] = ch;
videoram[ega_cursor * 2 + 1] = STYLE;
}
}
static void ega_putchar(outdev_t *dev __attribute__((unused)), const char ch, bool silent)
{
ipl_t ipl;
ipl = interrupts_disable();
spinlock_lock(&egalock);
switch (ch) {
case '\n':
ega_cursor = (ega_cursor + EGA_COLS) - ega_cursor % EGA_COLS;
break;
case '\t':
ega_cursor = (ega_cursor + 8) - ega_cursor % 8;
break;
case '\b':
if (ega_cursor % EGA_COLS)
ega_cursor--;
break;
default:
ega_display_char(ch, silent);
ega_cursor++;
break;
}
ega_check_cursor();
if (!silent)
ega_move_cursor();
spinlock_unlock(&egalock);
interrupts_restore(ipl);
}
static outdev_t ega_console;
static outdev_operations_t ega_ops = {
.write = ega_putchar
};
void ega_init(ioport8_t *base, uintptr_t videoram_phys)
{
/* Initialize the software structure. */
ega_base = base;
backbuf
= (uint8_t *) malloc(EGA_VRAM_SIZE
, 0); if (!backbuf)
panic("Unable to allocate backbuffer.");
videoram = (uint8_t *) hw_map(videoram_phys, EGA_VRAM_SIZE);
/* Synchronize the back buffer and cursor position. */
memcpy(backbuf
, videoram
, EGA_VRAM_SIZE
); ega_sync_cursor();
outdev_initialize("ega", &ega_console, &ega_ops);
stdout = &ega_console;
sysinfo_set_item_val("fb", NULL, true);
sysinfo_set_item_val("fb.kind", NULL, 2);
sysinfo_set_item_val("fb.width", NULL, EGA_COLS);
sysinfo_set_item_val("fb.height", NULL, EGA_ROWS);
sysinfo_set_item_val("fb.blinking", NULL, true);
sysinfo_set_item_val("fb.address.physical", NULL, videoram_phys);
}
void ega_redraw(void)
{
memcpy(videoram
, backbuf
, EGA_VRAM_SIZE
); ega_move_cursor();
ega_show_cursor();
}
/** @}
*/