blob: a52ba6dc1fb2b7b5cee14a08be9952d4fcbb52c6 [file] [log] [blame]
/* SPDX-License-Identifier: GPL-2.0-or-later */
#include <pc80/vga.h>
#include <pc80/vga_io.h>
#include <string.h>
#include "vga.h"
/*
* pci io enable should've happened before
*/
void
vga_io_init(void)
{
vga_enable_mask(0x01, 0x01);
/* cr io is at 0x3D4/0x3D5 */
vga_misc_mask(0x01, 0x01);
/* clear cr0-7 protection */
vga_cr_mask(0x11, 0x00, 0x80);
}
/*
*
*/
static void
vga_fb_init(void)
{
vga_sr_write(0x02, 0x03);
vga_sr_write(0x03, 0x00);
vga_sr_write(0x04, 0x02); /* access all 256kB */
vga_gr_write(0x00, 0x00);
vga_gr_write(0x01, 0x00);
vga_gr_write(0x02, 0x00);
vga_gr_write(0x03, 0x00);
vga_gr_write(0x04, 0x00);
vga_gr_write(0x05, 0x10);
vga_gr_write(0x06, 0x0E); /* map at 0xB8000 */
vga_gr_write(0x07, 0x00);
vga_gr_write(0x08, 0xFF);
/* o/e enable: RAM enable */
vga_misc_mask(0x22, 0x22);
}
/*
*
*/
static void
vga_fb_clear(void)
{
memset((void *)VGA_FB, 0x00, 0x8000);
}
/*
*
*/
static void
vga_palette_init(void)
{
size_t i;
/* set up attribute registers */
for (i = 0; i < 0x10; i++)
vga_ar_write(i, i);
vga_ar_write(0x10, 0x0c);
vga_ar_write(0x11, 0x00);
vga_ar_write(0x12, 0x0F);
vga_ar_write(0x13, 0x08);
vga_ar_write(0x14, 0x00);
vga_palette_disable();
/* load actual palette */
vga_dac_mask_write(0xFF);
for (i = 0; i < 0x100; i++) {
vga_dac_write_address(i);
vga_dac_data_write(default_vga_palette[i].red);
vga_dac_data_write(default_vga_palette[i].green);
vga_dac_data_write(default_vga_palette[i].blue);
}
}
/*
*
*/
static void
vga_mode_set(int hdisplay, int hblankstart, int hsyncstart, int hsyncend,
int hblankend, int htotal, int vdisplay, int vblankstart,
int vsyncstart, int vsyncend, int vblankend, int vtotal,
int stride)
{
/* htotal: 2080 */
htotal /= 8;
htotal -= 5;
vga_cr_write(0x00, htotal);
/* hdisplay: 2048 */
hdisplay /= 8;
hdisplay -= 1;
vga_cr_write(0x01, hdisplay);
/* hblankstart: 2048 */
hblankstart /= 8;
hblankstart -= 1;
vga_cr_write(0x02, hblankstart);
/* hblankend: hblankstart + 512 */
hblankend /= 8;
hblankend -= 1;
vga_cr_mask(0x03, hblankend, 0x1F);
vga_cr_mask(0x05, hblankend << 2, 0x80);
/* hsyncstart: 255 * 8: 2040 */
vga_cr_write(0x04, hsyncstart / 8);
/* hsyncend: hsyncstart + 255 */
vga_cr_mask(0x05, hsyncend / 8, 0x1F);
/* vtotal: 1025 */
vtotal -= 2;
vga_cr_write(0x06, vtotal);
vga_cr_mask(0x07, vtotal >> 8, 0x01);
vga_cr_mask(0x07, vtotal >> 4, 0x20);
/* vdisplay: 1024 */
vdisplay -= 1;
vga_cr_write(0x12, vdisplay);
vga_cr_mask(0x07, vdisplay >> 7, 0x02);
vga_cr_mask(0x07, vdisplay >> 3, 0x40);
/* vblankstart: 1024 */
vblankstart -= 1;
vga_cr_write(0x15, vblankstart);
vga_cr_mask(0x07, vblankstart >> 5, 0x08);
vga_cr_mask(0x09, vblankstart >> 4, 0x20);
/* vblankend: vblankstart + 256 */
vblankend -= 1;
vga_cr_write(0x16, vblankend);
/* vsyncstart: 1023 */
vga_cr_write(0x10, vsyncstart);
vga_cr_mask(0x07, vsyncstart >> 6, 0x04);
vga_cr_mask(0x07, vsyncstart >> 2, 0x80);
/* vsyncend: vsyncstart + 16 */
vga_cr_mask(0x11, vsyncend, 0x0F);
/* stride */
vga_cr_write(0x13, stride / 8);
/* line compare */
vga_cr_write(0x18, 0xFF);
vga_cr_mask(0x07, 0x10, 0x10);
vga_cr_mask(0x09, 0x40, 0x40);
vga_misc_mask(0x44, 0xCC); /* set up clock: 27mhz and h/vsync */
vga_cr_mask(0x09, 0x00, 0x80); /* disable doublescan */
}
static void
vga_font_8x16_load(void)
{
unsigned char *p;
size_t i, j;
unsigned char sr2, sr4, gr5, gr6;
#define height 16
#define count 256
sr2 = vga_sr_read(0x02);
sr4 = vga_sr_read(0x04);
gr5 = vga_gr_read(0x05);
gr6 = vga_gr_read(0x06);
/* disable odd/even */
vga_sr_mask(0x04, 0x04, 0x04);
vga_gr_mask(0x05, 0x00, 0x10);
vga_gr_mask(0x06, 0x00, 0x02);
/* plane 2 */
vga_sr_write(0x02, 0x04);
p = (unsigned char *)VGA_FB;
for (i = 0; i < count; i++) {
for (j = 0; j < 32; j++) {
if (j < height)
*p = vga_font_8x16[i][j];
else
*p = 0x00;
p++;
}
}
vga_gr_write(0x06, gr6);
vga_gr_write(0x05, gr5);
vga_sr_write(0x04, sr4);
vga_sr_write(0x02, sr2);
/* set up font size */
vga_cr_mask(0x09, 16 - 1, 0x1F);
}
/*
*
*/
void
vga_cursor_enable(int enable)
{
if (enable)
vga_cr_mask(0x0A, 0x00, 0x20);
else
vga_cr_mask(0x0A, 0x20, 0x20);
}
/*
*
*/
void
vga_cursor_reset(void)
{
vga_cr_write(0x0A, 0x2E);
vga_cr_write(0x0B, 0x0E);
vga_cr_write(0x0E, 0x00);
vga_cr_write(0x0F, 0x00);
}
/*
*
*/
void
vga_cursor_set(unsigned int line, unsigned int character)
{
unsigned int offset = (VGA_COLUMNS * line + character) & 0xFFFF;
vga_cr_write(0x0A, 0x0E);
vga_cr_write(0x0B, 0x0E);
vga_cr_write(0x0E, offset >> 8);
vga_cr_write(0x0F, offset & 0xFF);
}
/*
*
*/
void
vga_frame_set(unsigned int line, unsigned int character)
{
unsigned int offset = (VGA_COLUMNS * line + character) & 0xFFFF;
vga_cr_write(0x0C, offset >> 8);
vga_cr_write(0x0D, offset & 0xFF);
}
static void
vga_write_at_offset(unsigned int line, unsigned int offset, const char *string)
{
if (!string)
return;
unsigned short *p = (unsigned short *)VGA_FB + (VGA_COLUMNS * line) + offset;
size_t i, len = strlen(string);
for (i = 0; i < (VGA_COLUMNS - offset); i++) {
if (i < len)
p[i] = 0x0F00 | string[i];
else
p[i] = 0x0F00;
}
}
/*
* simply fills a line with the given string.
*/
void
vga_line_write(unsigned int line, const char *string)
{
vga_write_at_offset(line, 0, string);
}
void
vga_write_text(enum VGA_TEXT_ALIGNMENT alignment, unsigned int line, const char *string)
{
char str[VGA_COLUMNS * VGA_LINES] = {0};
memcpy(str, string, strnlen(string, sizeof(str) - 1));
char *token = strtok(str, "\n");
while (token != NULL) {
size_t offset = VGA_COLUMNS - strnlen(token, VGA_COLUMNS);
switch (alignment) {
case VGA_TEXT_CENTER:
vga_write_at_offset(line++, offset/2, token);
break;
case VGA_TEXT_RIGHT:
vga_write_at_offset(line++, offset, token);
break;
case VGA_TEXT_LEFT:
default:
vga_write_at_offset(line++, 0, token);
break;
}
token = strtok(NULL, "\n");
}
}
/*
* set up everything to get a basic 80x25 textmode.
*/
void
vga_textmode_init(void)
{
vga_sr_write(0x00, 0x01); /* clear reset */
vga_sr_write(0x01, 0x00);
/* set up cr */
vga_cr_mask(0x03, 0x80, 0xE0);
vga_cr_mask(0x05, 0x00, 0x60);
vga_cr_write(0x08, 0x00);
vga_cr_write(0x14, 0x00); /* */
vga_cr_write(0x17, 0x23);
vga_palette_init();
vga_mode_set(640, 648, 680, 776, 792, 800,
400, 407, 412, 414, 442, 449, 320);
vga_cursor_reset();
vga_frame_set(0, 0);
vga_fb_init();
vga_fb_clear();
vga_font_8x16_load();
vga_sr_mask(0x00, 0x02, 0x02); /* take us out of reset */
vga_cr_mask(0x17, 0x80, 0x80); /* sync! */
}