add wbadaddr routine for Harris write-only memory

SCCS-vsn: sys/tahoe/stand/machdep.c 1.3

diff --git a/usr/src/sys/tahoe/stand/machdep.c b/usr/src/sys/tahoe/stand/machdep.c
index 1e68fae..0eb474b 100644 (file)
--- a/usr/src/sys/tahoe/stand/machdep.c
+++ b/usr/src/sys/tahoe/stand/machdep.c
@@ -1,4 +1,4 @@
-/*     machdep.c       1.2     86/12/18        */
+/*     machdep.c       1.3     87/10/27        */

 
 #include "../tahoe/mem.h"
 #include "../tahoe/mtpr.h"
 
 #include "../tahoe/mem.h"
 #include "../tahoe/mtpr.h"


@@ -43,6 +43,31 @@ ENTRY(badaddr, R5|R4|R3|R2|R1)
 1:     bbc     $1,r4,1f; tstw  (r3)
 1:     bbc     $2,r4,1f; tstl  (r3)
 1:     clrl    r0                      # made it w/o machine checks
 1:     bbc     $1,r4,1f; tstw  (r3)
 1:     bbc     $2,r4,1f; tstl  (r3)
 1:     clrl    r0                      # made it w/o machine checks

+2:     movl    r2,*$BERVEC
+       mtpr    r1,$IPL
+       mtpr    r5,$SCBB
+       ret
+
+/*
+ * wbadaddr(addr, len, value)
+ *     see if write of value to addr with a len type instruction causes
+ *     a machine check
+ *     len is length of access (1=byte, 2=short, 4=long)
+ *     r0 = 0 means good(exists); r0 =1 means does not exist.
+ */
+ENTRY(wbadaddr, R5|R4|R3|R2|R1)
+       mfpr    $IPL,r1
+       mtpr    $HIGH,$IPL
+       mfpr    $SCBB,r5
+       mtpr    $0,$SCBB
+       movl    *$BERVEC,r2
+       movl    4(fp),r3
+       movl    8(fp),r4
+       movab   9f,*$BERVEC
+       bbc     $0,r4,1f; movb  15(fp), (r3)
+1:     bbc     $1,r4,1f; movw  14(fp), (r3)
+1:     bbc     $2,r4,1f; movl  12(fp), (r3)
+1:     clrl    r0                      # made it w/o machine checks

 2:     movl    r2,*$BERVEC
        mtpr    r1,$IPL
        mtpr    r5,$SCBB
 2:     movl    r2,*$BERVEC
        mtpr    r1,$IPL
        mtpr    r5,$SCBB