kexts: fbcon: add 8x16 bitmap font

kexts/drivers/tty/fbcon/extension.yaml

@@ -8,3 +8,4 @@ sources:
   - main.c
   - fbcon.c
   - vgacon.c
+  - u_vga16.c

kexts/drivers/tty/fbcon/fbcon.c

@@ -1,4 +1,5 @@
 #include <socks/tty.h>
+#include "u_vga16.h"
 #include "fbcon.h"
 
 #define CELL_WIDTH 8
@@ -87,5 +88,7 @@ kern_status_t init_fbcon_console(struct device *tty, struct device *fb)
 	priv->tty_ops = &fbcon_ops;
 	tty->dev_priv = priv;
 
+	memset(priv->fb_pixels, 0x00, fb_mode.fb_yres * fb_mode.fb_stride);
+
 	return KERN_OK;
 }

kexts/drivers/tty/fbcon/u_vga16.h

@@ -0,0 +1,15 @@
+#ifndef U_VGA16_H_
+#define U_VGA16_H_
+
+struct bitmap_font {
+	unsigned char Width;		///< max. character width
+	unsigned char Height;		///< character height
+	unsigned short Chars;		///< number of characters in font
+	const unsigned char *Widths;	///< width of each character
+	const unsigned short *Index;	///< encoding to character index
+	const unsigned char *Bitmap;	///< bitmap of all characters
+};
+
+extern const struct bitmap_font fbcon_font;
+
+#endif