| /* |
| * Copyright (c) 2018 Intel Corporation |
| * |
| * SPDX-License-Identifier: Apache-2.0 |
| */ |
| #include "shared-page.h" |
| |
| /* Super-primitive VGA text console output-only "terminal" driver */ |
| |
| static inline unsigned short *vga_row(int row) |
| { |
| return ((unsigned short *)0xb8000) + 80 * row; |
| } |
| |
| /* Foreground color is four bit, high to low: "intensity", red, green, |
| * blue. Normal text is low intensity, so 0b0111 (7) is standard. |
| * The high nybble is the background color. |
| */ |
| static inline void vga_put(int ch, int color, int row, int col) |
| { |
| unsigned short *rp = vga_row(row); |
| |
| rp[col] = (color << 8) | ch; |
| } |
| |
| static inline void vgacon_putc(char c) |
| { |
| if (_shared.vgacol == 80) { |
| for (int r = 0; r < 24; r++) { |
| for (int c = 0; c < 80; c++) { |
| vga_row(r)[c] = vga_row(r+1)[c]; |
| } |
| } |
| for (int c = 0; c < 80; c++) { |
| vga_row(24)[c] = 0x9000; |
| } |
| _shared.vgacol = 0; |
| } |
| |
| if (c == '\n') { |
| _shared.vgacol = 80; |
| } else if (c == '\r') { |
| _shared.vgacol = 0; |
| } else { |
| vga_put(c, 0x1f, 24, _shared.vgacol++); |
| } |
| } |
