Default DMA-reachable address constraints to the whole address space, and

narrow these in the various ipXX_machdep.c. On IP22-like systems, narrow
them to 28 bit physical addresses, but unpessimize this by extending this
to 32 bit after autoconf, if no 28-bit limited hpc(4) device has been found.
Since physical memory on these systems start at 128MB, this means that Indigo
systems with more than 128MB memory will behave correctly (and so will Indy
systems with E++ boards and more than 128MB memory).

1 files changed, 2 insertions, 10 deletions

diff --git a/share/man/man4/man4.sgi/hpc.4 b/share/man/man4/man4.sgi/hpc.4
index ad259a038ed..d31d90c4abe 100644
--- a/share/man/man4/man4.sgi/hpc.4
+++ b/share/man/man4/man4.sgi/hpc.4
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: hpc.4,v 1.5 2012/03/29 08:47:35 jmc Exp $
+.\"	$OpenBSD: hpc.4,v 1.6 2012/04/03 21:17:34 miod Exp $
 .\"	$NetBSD: hpc.4,v 1.12 2008/04/30 13:10:56 martin Exp $
 .\"
 .\" Copyright (c) 2002 The NetBSD Foundation, Inc.
@@ -28,7 +28,7 @@
 .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 .\" POSSIBILITY OF SUCH DAMAGE.
 .\"
-.Dd $Mdocdate: March 29 2012 $
+.Dd $Mdocdate: April 3 2012 $
 .Dt HPC 4 sgi
 .Os
 .Sh NAME
@@ -81,11 +81,3 @@ Zilog 8530 (ZSCC) Serial Communications Controller
 .Xr gio 4 ,
 .Xr imc 4 ,
 .Xr intro 4
-.Sh BUGS
-.Nm
-revisions 1 and 1.5 support DMA buffer pointers of only 28 bits
-and may therefore only address 256 megabytes of memory.
-The R4k Indigo and Indy are the only systems that support sufficient
-memory to illustrate this drawback.
-A software workaround is not currently implemented.
-Revision 3, with 32-bit pointers, does not have this limitation.