stacks: Don't update the A20 settings if they haven't changed

The A20 setting is almost always enabled - only issue an outb() if the
A20 is actually changing.  This reduces the number of outb() calls.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
3 files changed
tree: c33661243dc30366b5fe3360a0ae513637834cb6
  1. docs/
  2. scripts/
  3. src/
  4. vgasrc/
  5. .gitignore
  6. COPYING
  7. COPYING.LESSER
  8. Makefile
  9. README