drvs/video: add useful defines and constants for working with VGA

1 files changed, 45 insertions, 0 deletions

diff --git a/drivers/video/vga.h b/drivers/video/vga.h
new file mode 100644
index 0000000..e7ff29f
--- /dev/null
+++ b/drivers/video/vga.h
@@ -0,0 +1,45 @@
+#ifndef DRIVERS_VIDEO_VGA_H
+#define DRIVERS_VIDEO_VGA_H
+
+#include <stddef.h>
+
+/* VGA Video RAM base addresses */
+#define VGA_VRAM_BC 0xB8000 // Color
+#define VGA_VRAM_BM 0xB0000 // Monochrome
+
+/* VGA index register ports */
+#define VGA_CRTC_IC 0x3D4 // Color
+#define VGA_CRTC_IM 0x3B4 // Monochrome
+
+/* VGA data register ports */
+#define VGA_CRTC_DC 0x3D5 // Color
+#define VGA_CRTC_DM 0x3B5 // Monochorme
+
+/* VGA CRTC register indices */
+#define VGA_CRTC_CURSOR_H 0x0E
+#define VGA_CRTC_CURSOR_L 0x0F
+
+/* Hardware text mode color constants. */
+enum vga_colors {
+	VGA_COLOR_BLACK = 0,
+	VGA_COLOR_BLUE = 1,
+	VGA_COLOR_GREEN = 2,
+	VGA_COLOR_CYAN = 3,
+	VGA_COLOR_RED = 4,
+	VGA_COLOR_MAGENTA = 5,
+	VGA_COLOR_BROWN = 6,
+	VGA_COLOR_LIGHT_GREY = 7,
+	VGA_COLOR_DARK_GREY = 8,
+	VGA_COLOR_LIGHT_BLUE = 9,
+	VGA_COLOR_LIGHT_GREEN = 10,
+	VGA_COLOR_LIGHT_CYAN = 11,
+	VGA_COLOR_LIGHT_RED = 12,
+	VGA_COLOR_LIGHT_MAGENTA = 13,
+	VGA_COLOR_LIGHT_BROWN = 14,
+	VGA_COLOR_WHITE = 15
+};
+
+#define VGA_ENTRY_COLOR(fg, bg) ((uint8_t)(fg | bg << 4))
+#define VGA_ENTRY(uc, color) ((uint16_t) uc | (uint16_t) color << 8)
+
+#endif /* DRIVERS_VIDEO_VGA_H */