9 Linear access to the frame buffer

Contents of this section

The stock BSD/386 1.1 kernel has problems when trying to mmap the frame buffer as a linear ( unbanked ) memory area in high memory. This patch removes the check in /sys/i386/isa/vga.c that disables mmapping the frame buffer in linear mode. Please consult the BSD/386 1.1 release notes for instructions on how to build a new kernel.

• save the patch below in a separate file.
• cd to /sys/i386/isa.
• apply the patch with ``patch -p <the_separate_patch_file''
• rebuild and install the new kernel.
• reboot.

*** vga.c.orig  Sun Dec 19 09:35:01 1993
--- vga.c       Mon Oct 24 01:38:44 1994
***************
*** 159,165 ****
  #if 0
        if (off + NBPG > vgap->vga_mem_size)
                return (-1);
! #else
        if (off + NBPG > IOM_END)
                return (-1);
  #endif
--- 159,165 ----
  #if 0
        if (off + NBPG > vgap->vga_mem_size)
                return (-1);
! /*#else*/
        if (off + NBPG > IOM_END)
                return (-1);
  #endif

$XConsortium: Bsdi.sgml,v 1.3 95/01/23 15:34:39 kaleb Exp $
$XFree86: xc/programs/Xserver/hw/xfree86/doc/sgml/Bsdi.sgml,v 3.9 1995/01/28 16:01:18 dawes Exp $

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