document SCSI_REVPRI, MAPPEDCOPY, BUFFERS_UNMANAGED

SCCS-vsn: sys/hp300/DOC/Options 8.2

diff --git a/usr/src/sys/hp300/DOC/Options b/usr/src/sys/hp300/DOC/Options
index 573770d..f6a8ac1 100644 (file)
--- a/usr/src/sys/hp300/DOC/Options
+++ b/usr/src/sys/hp300/DOC/Options
@@ -100,3 +100,28 @@ STACKCHECK
           exception frame has been popped.
        This option can degrade performance considerably, use it only if
        you suspect a problem with kernel stacks.
           exception frame has been popped.
        This option can degrade performance considerably, use it only if
        you suspect a problem with kernel stacks.

+
+SCSI_REVPRI
+       Changes autoconf to start matching logical SCSI devices starting
+       at slave 6 and working backwards instead of starting at slave 0
+       and working up.  Later releases of the HP boot ROM search for
+       boot devices in this manner.  This is apparently the order in
+       which priority is given to slaves on the host adaptor.  Define
+       this if you use wildcarding and want to stay in sync with the
+       boot ROM's strategy.
+
+MAPPEDCOPY
+       Use page remapping to do large copyin/copyouts.  When defined
+       the default is to use mapped copy for operations on one page
+       or more except on machines with virtually-indexed caches.
+       See initcpu() in machdep.c
+
+BUFFERS_UNMANAGED
+       Set up the buffer cache "below" the machine independent VM.
+       Normally, in startup() we use vm_map operations to initially
+       assign physical memory to the buffers.  This creates a map with
+       a huge number of map entries (twice the number of buffers)
+       which serve no purpose since remaining buffer operations
+       (i.e. pagemove) work below the MI layer anyway.  Defining this
+       symbol will cause startup() to use pmap operations to map the
+       initial pages leaving the buffer_map one big entry.