diff -ur /usr/ports/x11/XFree86/work/xc/programs/Xserver/hw/xfree86/os-support/shared/bios_devmem.c programs/Xserver/hw/xfree86/os-support/shared/bios_devmem.c
--- /usr/ports/x11/XFree86/work/xc/programs/Xserver/hw/xfree86/os-support/shared/bios_devmem.c	Mon Dec 23 06:50:58 1996
+++ programs/Xserver/hw/xfree86/os-support/shared/bios_devmem.c	Tue Dec  8 10:05:56 1998
@@ -60,25 +60,7 @@
    *  re: boundaries and sizes and such...
    */
 
-/*
- * The Jensen lacks dense memory, thus we have to address the bus via
- * the sparse addressing scheme.
- *
- * Martin Ostermann (ost@comnets.rwth-aachen.de) - Apr.-Sep. 1996
- */
-
-#ifdef TEST_JENSEN_CODE /* define to test the Sparse addressing on a non-Jensen */
-#define SPARSE (5)
-#define isJensen (1)
-#else
-#define isJensen (!_bus_base())
-#define SPARSE (7)
-#endif
-
-extern unsigned long _bus_base(void);
-extern unsigned long _bus_base_sparse(void);
-#define BUS_BASE (isJensen ? _bus_base_sparse() : _bus_base())
-#define JENSEN_SHIFT(x) (isJensen ? ((long)x<<SPARSE) : (long)x)
+extern u_int64_t dense_base(void);
 
 #define SIZE (64*1024)
 
@@ -92,8 +74,8 @@
 		return(-1);
 	}
 
-	base = mmap((caddr_t)0, JENSEN_SHIFT(SIZE), PROT_READ,
-		    MAP_SHARED, fd, (off_t)(JENSEN_SHIFT(Base) + BUS_BASE));
+	base = mmap((caddr_t)0, SIZE, PROT_READ,
+		    MAP_SHARED, fd, (off_t)Base + dense_base());
 
 	if (base == (caddr_t)-1UL)
 	{
@@ -102,9 +84,9 @@
 		return(-1);
 	}
 
-	SlowBCopyFromBus(base+JENSEN_SHIFT(Offset), Buf, Len);
+	SlowBCopyFromBus(base+Offset, Buf, Len);
 
-	munmap((caddr_t)JENSEN_SHIFT(base), JENSEN_SHIFT(SIZE));
+	munmap((caddr_t)base, SIZE);
 	close(fd);
 	return(Len);