limine/common/drivers/vga_textmode.c

369 lines
11 KiB
C

#if defined (BIOS)
#include <stdint.h>
#include <stddef.h>
#include <stdbool.h>
#include <drivers/vga_textmode.h>
#include <sys/cpu.h>
#include <lib/real.h>
#include <lib/libc.h>
#include <lib/misc.h>
#include <lib/term.h>
#include <mm/pmm.h>
#define VIDEO_BOTTOM ((VD_ROWS * VD_COLS) - 1)
static void draw_cursor(struct textmode_context *ctx) {
uint8_t pal = ctx->back_buffer[ctx->cursor_offset + 1];
ctx->video_mem[ctx->cursor_offset + 1] = ((pal & 0xf0) >> 4) | ((pal & 0x0f) << 4);
}
static void text_save_state(struct flanterm_context *_ctx) {
struct textmode_context *ctx = (void *)_ctx;
ctx->saved_state_text_palette = ctx->text_palette;
ctx->saved_state_cursor_offset = ctx->cursor_offset;
}
static void text_restore_state(struct flanterm_context *_ctx) {
struct textmode_context *ctx = (void *)_ctx;
ctx->text_palette = ctx->saved_state_text_palette;
ctx->cursor_offset = ctx->saved_state_cursor_offset;
}
static void text_swap_palette(struct flanterm_context *_ctx) {
struct textmode_context *ctx = (void *)_ctx;
ctx->text_palette = (ctx->text_palette << 4) | (ctx->text_palette >> 4);
}
static void text_scroll(struct flanterm_context *_ctx) {
struct textmode_context *ctx = (void *)_ctx;
// move the text up by one row
for (size_t i = _ctx->scroll_top_margin * VD_COLS;
i < (_ctx->scroll_bottom_margin - 1) * VD_COLS; i++) {
ctx->back_buffer[i] = ctx->back_buffer[i + VD_COLS];
}
// clear the last line of the screen
for (size_t i = (_ctx->scroll_bottom_margin - 1) * VD_COLS;
i < _ctx->scroll_bottom_margin * VD_COLS; i += 2) {
ctx->back_buffer[i] = ' ';
ctx->back_buffer[i + 1] = ctx->text_palette;
}
}
static void text_revscroll(struct flanterm_context *_ctx) {
struct textmode_context *ctx = (void *)_ctx;
// move the text up by one row
for (size_t i = (_ctx->scroll_bottom_margin - 1) * VD_COLS - 2; ; i--) {
ctx->back_buffer[i + VD_COLS] = ctx->back_buffer[i];
if (i == _ctx->scroll_top_margin * VD_COLS) {
break;
}
}
// clear the first line of the screen
for (size_t i = _ctx->scroll_top_margin * VD_COLS;
i < (_ctx->scroll_top_margin + 1) * VD_COLS; i += 2) {
ctx->back_buffer[i] = ' ';
ctx->back_buffer[i + 1] = ctx->text_palette;
}
}
static void text_clear(struct flanterm_context *_ctx, bool move) {
struct textmode_context *ctx = (void *)_ctx;
for (size_t i = 0; i < VIDEO_BOTTOM; i += 2) {
ctx->back_buffer[i] = ' ';
ctx->back_buffer[i + 1] = ctx->text_palette;
}
if (move) {
ctx->cursor_offset = 0;
}
}
static void text_full_refresh(struct flanterm_context *_ctx) {
struct textmode_context *ctx = (void *)_ctx;
for (size_t i = 0; i < VD_ROWS * VD_COLS; i++) {
ctx->video_mem[i] = ctx->front_buffer[i];
ctx->back_buffer[i] = ctx->front_buffer[i];
}
if (_ctx->cursor_enabled) {
draw_cursor(ctx);
ctx->old_cursor_offset = ctx->cursor_offset;
}
}
static void text_double_buffer_flush(struct flanterm_context *_ctx) {
struct textmode_context *ctx = (void *)_ctx;
if (_ctx->cursor_enabled) {
draw_cursor(ctx);
}
if (ctx->cursor_offset != ctx->old_cursor_offset || _ctx->cursor_enabled == false) {
ctx->video_mem[ctx->old_cursor_offset + 1] = ctx->back_buffer[ctx->old_cursor_offset + 1];
}
for (size_t i = 0; i < VD_ROWS * VD_COLS; i++) {
if (ctx->back_buffer[i] == ctx->front_buffer[i]) {
continue;
}
ctx->front_buffer[i] = ctx->back_buffer[i];
if (_ctx->cursor_enabled && i == ctx->cursor_offset + 1) {
continue;
}
ctx->video_mem[i] = ctx->back_buffer[i];
}
if (_ctx->cursor_enabled) {
ctx->old_cursor_offset = ctx->cursor_offset;
}
}
static void text_get_cursor_pos(struct flanterm_context *_ctx, size_t *x, size_t *y) {
struct textmode_context *ctx = (void *)_ctx;
*x = (ctx->cursor_offset % VD_COLS) / 2;
*y = ctx->cursor_offset / VD_COLS;
}
static void text_move_character(struct flanterm_context *_ctx, size_t new_x, size_t new_y, size_t old_x, size_t old_y) {
struct textmode_context *ctx = (void *)_ctx;
if (old_x >= VD_COLS / 2 || old_y >= VD_ROWS
|| new_x >= VD_COLS / 2 || new_y >= VD_ROWS) {
return;
}
ctx->back_buffer[new_y * VD_COLS + new_x * 2] = ctx->back_buffer[old_y * VD_COLS + old_x * 2];
}
static void text_set_cursor_pos(struct flanterm_context *_ctx, size_t x, size_t y) {
struct textmode_context *ctx = (void *)_ctx;
if (x >= VD_COLS / 2) {
if ((int)x < 0) {
x = 0;
} else {
x = VD_COLS / 2 - 1;
}
}
if (y >= VD_ROWS) {
if ((int)y < 0) {
y = 0;
} else {
y = VD_ROWS - 1;
}
}
ctx->cursor_offset = y * VD_COLS + x * 2;
}
static uint8_t ansi_colours[] = { 0, 4, 2, 6, 1, 5, 3, 7 };
static void text_set_text_fg(struct flanterm_context *_ctx, size_t fg) {
struct textmode_context *ctx = (void *)_ctx;
ctx->text_palette = (ctx->text_palette & 0xf0) | ansi_colours[fg];
}
static void text_set_text_bg(struct flanterm_context *_ctx, size_t bg) {
struct textmode_context *ctx = (void *)_ctx;
ctx->text_palette = (ctx->text_palette & 0x0f) | (ansi_colours[bg] << 4);
}
static void text_set_text_fg_bright(struct flanterm_context *_ctx, size_t fg) {
struct textmode_context *ctx = (void *)_ctx;
ctx->text_palette = (ctx->text_palette & 0xf0) | (ansi_colours[fg] | (1 << 3));
}
static void text_set_text_bg_bright(struct flanterm_context *_ctx, size_t bg) {
struct textmode_context *ctx = (void *)_ctx;
ctx->text_palette = (ctx->text_palette & 0x0f) | ((ansi_colours[bg] | (1 << 3)) << 4);
}
static void text_set_text_fg_rgb(struct flanterm_context *ctx, uint32_t n) {
(void)ctx;
(void)n;
}
static void text_set_text_bg_rgb(struct flanterm_context *ctx, uint32_t n) {
(void)ctx;
(void)n;
}
static void text_set_text_fg_default(struct flanterm_context *_ctx) {
struct textmode_context *ctx = (void *)_ctx;
ctx->text_palette = (ctx->text_palette & 0xf0) | 7;
}
static void text_set_text_bg_default(struct flanterm_context *_ctx) {
struct textmode_context *ctx = (void *)_ctx;
ctx->text_palette &= 0x0f;
}
static void text_set_text_fg_default_bright(struct flanterm_context *_ctx) {
struct textmode_context *ctx = (void *)_ctx;
ctx->text_palette = (ctx->text_palette & 0xf0) | (7 | (1 << 3));
}
static void text_set_text_bg_default_bright(struct flanterm_context *_ctx) {
struct textmode_context *ctx = (void *)_ctx;
ctx->text_palette = (ctx->text_palette & 0x0f) | ((1 << 3) << 4);
}
static void text_putchar(struct flanterm_context *_ctx, uint8_t c) {
struct textmode_context *ctx = (void *)_ctx;
ctx->back_buffer[ctx->cursor_offset] = c;
ctx->back_buffer[ctx->cursor_offset + 1] = ctx->text_palette;
if (ctx->cursor_offset / VD_COLS == _ctx->scroll_bottom_margin - 1
&& ctx->cursor_offset % VD_COLS == VD_COLS - 2) {
if (_ctx->scroll_enabled) {
text_scroll(_ctx);
ctx->cursor_offset -= ctx->cursor_offset % VD_COLS;
}
} else if (ctx->cursor_offset >= (VIDEO_BOTTOM - 1)) {
ctx->cursor_offset -= ctx->cursor_offset % VD_COLS;
} else {
ctx->cursor_offset += 2;
}
}
static void text_deinit(struct flanterm_context *_ctx, void (*_free)(void *, size_t)) {
struct textmode_context *ctx = (void *)_ctx;
if (ctx->back_buffer != NULL) {
_free(ctx->back_buffer, VD_ROWS * VD_COLS);
ctx->back_buffer = NULL;
}
if (ctx->front_buffer != NULL) {
_free(ctx->front_buffer, VD_ROWS * VD_COLS);
ctx->front_buffer = NULL;
}
pmm_free(ctx, sizeof(struct textmode_context));
}
void vga_textmode_init(bool managed) {
term_notready();
if (quiet) {
return;
}
if (current_video_mode != 0x3) {
struct rm_regs r = {0};
r.eax = 0x0003;
rm_int(0x10, &r, &r);
current_video_mode = 0x3;
}
terms = ext_mem_alloc(sizeof(void *));
terms_i = 1;
terms[0] = ext_mem_alloc(sizeof(struct textmode_context));
struct flanterm_context *term = terms[0];
struct textmode_context *ctx = (void *)term;
if (ctx->back_buffer == NULL) {
ctx->back_buffer = ext_mem_alloc(VD_ROWS * VD_COLS);
} else {
memset(ctx->back_buffer, 0, VD_ROWS * VD_COLS);
}
if (ctx->front_buffer == NULL) {
ctx->front_buffer = ext_mem_alloc(VD_ROWS * VD_COLS);
} else {
memset(ctx->front_buffer, 0, VD_ROWS * VD_COLS);
}
ctx->cursor_offset = 0;
ctx->text_palette = 0x07;
ctx->video_mem = (volatile uint8_t *)0xb8000;
text_clear(term, false);
// VGA cursor code taken from: https://wiki.osdev.org/Text_Mode_Cursor
if (!managed) {
term->cursor_enabled = false;
outb(0x3d4, 0x0a);
outb(0x3d5, (inb(0x3d5) & 0xc0) | 14);
outb(0x3d4, 0x0b);
outb(0x3d5, (inb(0x3d5) & 0xe0) | 15);
outb(0x3d4, 0x0f);
outb(0x3d5, 0);
outb(0x3d4, 0x0e);
outb(0x3d5, 0);
struct rm_regs r = {0};
r.eax = 0x0200;
rm_int(0x10, &r, &r);
} else {
outb(0x3d4, 0x0a);
outb(0x3d5, 0x20);
}
text_double_buffer_flush(term);
if (managed && serial) {
term->cols = 80;
term->rows = 24;
} else {
term->cols = 80;
term->rows = 25;
}
term->raw_putchar = text_putchar;
term->clear = text_clear;
term->set_cursor_pos = text_set_cursor_pos;
term->get_cursor_pos = text_get_cursor_pos;
term->set_text_fg = text_set_text_fg;
term->set_text_bg = text_set_text_bg;
term->set_text_fg_bright = text_set_text_fg_bright;
term->set_text_bg_bright = text_set_text_bg_bright;
term->set_text_fg_rgb = text_set_text_fg_rgb;
term->set_text_bg_rgb = text_set_text_bg_rgb;
term->set_text_fg_default = text_set_text_fg_default;
term->set_text_bg_default = text_set_text_bg_default;
term->set_text_fg_default_bright = text_set_text_fg_default_bright;
term->set_text_bg_default_bright = text_set_text_bg_default_bright;
term->move_character = text_move_character;
term->scroll = text_scroll;
term->revscroll = text_revscroll;
term->swap_palette = text_swap_palette;
term->save_state = text_save_state;
term->restore_state = text_restore_state;
term->double_buffer_flush = text_double_buffer_flush;
term->full_refresh = text_full_refresh;
term->deinit = text_deinit;
flanterm_context_reinit(term);
if (!managed) {
term->cursor_enabled = false;
}
term->full_refresh(term);
if (!managed) {
term->deinit(term, pmm_free);
pmm_free(terms, sizeof(void *));
terms_i = 0;
terms = NULL;
term_backend = _NOT_READY;
} else {
term_backend = TEXTMODE;
}
}
#endif