EDID: add fields specialized to the needs of framebuffers

Now that we have horizontal display areas that are not multiples of 32  bytes,
things are more complex. We add three struct members (x, y resolution and
bytes per line) which are to be filled in by the mainboard as it sets the mode.

In future, the EDID code may take a stab at initializing these but the values are
context-dependent.

Change-Id: Ib9102d6bbf8c66931f5adb1029a04b881a982cfe
Signed-off-by: Ronald G. Minnich <rminnich@google.com>
Reviewed-on: https://gerrit.chromium.org/gerrit/60514
Tested-by: Ronald G. Minnich <rminnich@chromium.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Commit-Queue: Ronald G. Minnich <rminnich@chromium.org>
Reviewed-on: http://review.coreboot.org/4336
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

src/include/edid.h

@@ -55,6 +55,14 @@ struct edid {
 	unsigned int vso;
 	unsigned int vspw;
 	unsigned int vborder;
+	/* 3 variables needed for coreboot framebuffer.
+	 * In most cases, they are the same as the ha
+	 * and va variables, but not always, as in the
+	 * case of a 1366 wide display.
+	 */
+	u32 x_resolution;
+	u32 y_resolution;
+	u32 bytes_per_line;
 	/* it is unlikely we need these things. */
 	/* if one of these is non-zero, use that one. */
 	unsigned int aspect_landscape;