};
/* drivers/video/console/fbcon.c */
-extern char con2fb_map[MAX_NR_CONSOLES];
+extern signed char con2fb_map[MAX_NR_CONSOLES];
extern int set_con2fb_map(int unit, int newidx);
/*
* Scroll Method
*/
-/* Internal flags */
-#define __SCROLL_YPAN 0x001
-#define __SCROLL_YWRAP 0x002
-#define __SCROLL_YMOVE 0x003
-#define __SCROLL_YREDRAW 0x004
-#define __SCROLL_YMASK 0x00f
-#define __SCROLL_YFIXED 0x010
-#define __SCROLL_YNOMOVE 0x020
-#define __SCROLL_YPANREDRAW 0x040
-#define __SCROLL_YNOPARTIAL 0x080
-
-/* Only these should be used by the drivers */
-/* Which one should you use? If you have a fast card and slow bus,
- then probably just 0 to indicate fbcon should choose between
- YWRAP/YPAN+MOVE/YMOVE. On the other side, if you have a fast bus
- and even better if your card can do fonting (1->8/32bit painting),
- you should consider either SCROLL_YREDRAW (if your card is
- able to do neither YPAN/YWRAP), or SCROLL_YNOMOVE.
- The best is to test it with some real life scrolling (usually, not
- all lines on the screen are filled completely with non-space characters,
- and REDRAW performs much better on such lines, so don't cat a file
- with every line covering all screen columns, it would not be the right
- benchmark).
+/* There are several methods fbcon can use to move text around the screen:
+ *
+ * Operation Pan Wrap
+ *---------------------------------------------
+ * SCROLL_MOVE copyarea No No
+ * SCROLL_PAN_MOVE copyarea Yes No
+ * SCROLL_WRAP_MOVE copyarea No Yes
+ * SCROLL_REDRAW imageblit No No
+ * SCROLL_PAN_REDRAW imageblit Yes No
+ * SCROLL_WRAP_REDRAW imageblit No Yes
+ *
+ * (SCROLL_WRAP_REDRAW is not implemented yet)
+ *
+ * In general, fbcon will choose the best scrolling
+ * method based on the rule below:
+ *
+ * Pan/Wrap > accel imageblit > accel copyarea >
+ * soft imageblit > (soft copyarea)
+ *
+ * Exception to the rule: Pan + accel copyarea is
+ * preferred over Pan + accel imageblit.
+ *
+ * The above is typical for PCI/AGP cards. Unless
+ * overridden, fbcon will never use soft copyarea.
+ *
+ * If you need to override the above rule, set the
+ * appropriate flags in fb_info->flags. For example,
+ * to prefer copyarea over imageblit, set
+ * FBINFO_READS_FAST.
+ *
+ * Other notes:
+ * + use the hardware engine to move the text
+ * (hw-accelerated copyarea() and fillrect())
+ * + use hardware-supported panning on a large virtual screen
+ * + amifb can not only pan, but also wrap the display by N lines
+ * (i.e. visible line i = physical line (i+N) % yres).
+ * + read what's already rendered on the screen and
+ * write it in a different place (this is cfb_copyarea())
+ * + re-render the text to the screen
+ *
+ * Whether to use wrapping or panning can only be figured out at
+ * runtime (when we know whether our font height is a multiple
+ * of the pan/wrap step)
+ *
*/
-#define SCROLL_YREDRAW (__SCROLL_YFIXED|__SCROLL_YREDRAW)
-#define SCROLL_YNOMOVE (__SCROLL_YNOMOVE|__SCROLL_YPANREDRAW)
-/* SCROLL_YNOPARTIAL, used in combination with the above, is for video
- cards which can not handle using panning to scroll a portion of the
- screen without excessive flicker. Panning will only be used for
- whole screens.
- */
-/* Namespace consistency */
-#define SCROLL_YNOPARTIAL __SCROLL_YNOPARTIAL
+#define SCROLL_MOVE 0x001
+#define SCROLL_PAN_MOVE 0x002
+#define SCROLL_WRAP_MOVE 0x003
+#define SCROLL_REDRAW 0x004
+#define SCROLL_PAN_REDRAW 0x005
extern int fb_console_init(void);
git://git.onelab.eu / linux-2.6.git / blobdiff