MFC r270299 (dumbbell): vt_vga: When clearing video memory, don't read from it

The goal is to clear the video memory, in case an application drew to
  it. So the content shouldn't be loaded in the latches, it can't be
  trusted anyway.

  This improves a bit the window switch speed.

Sponsored by:	The FreeBSD Foundation
This commit is contained in:
emaste 2014-09-04 19:22:01 +00:00
parent f4cd1af86e
commit c3376ddfe1

View File

@ -609,7 +609,6 @@ vga_initialize(struct vt_device *vd, int textmode)
* planes. * planes.
*/ */
for (ofs = 0; ofs < VT_VGA_MEMSIZE; ofs++) { for (ofs = 0; ofs < VT_VGA_MEMSIZE; ofs++) {
MEM_READ1(sc, ofs);
MEM_WRITE1(sc, ofs, 0); MEM_WRITE1(sc, ofs, 0);
} }
} }