[src/trunk]: src/sys/arch/vax/vax Add code to support loading of kernel direc...

[ragge <ragge%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/5098dbd6cc0e
branches:  trunk
changeset: 494465:5098dbd6cc0e
user:      ragge <ragge%NetBSD.org@localhost>
date:      Thu Jul 06 17:37:40 2000 +0000

description:
Add code to support loading of kernel directly via MOP.
This is only intended for development purposes, not production use.

diffstat:

 sys/arch/vax/vax/subr.s |  54 +++++++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 52 insertions(+), 2 deletions(-)

diffs (72 lines):

diff -r ab3517f5e497 -r 5098dbd6cc0e sys/arch/vax/vax/subr.s
--- a/sys/arch/vax/vax/subr.s   Thu Jul 06 17:36:22 2000 +0000
+++ b/sys/arch/vax/vax/subr.s   Thu Jul 06 17:37:40 2000 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: subr.s,v 1.48 2000/06/10 14:59:38 ragge Exp $     */
+/*     $NetBSD: subr.s,v 1.49 2000/07/06 17:37:40 ragge Exp $     */
 
 /*
  * Copyright (c) 1994 Ludd, University of Lule}, Sweden.
@@ -49,11 +49,61 @@
 
                .text
 
+#ifdef KERNEL_LOADABLE_BY_MOP
+/*
+ * This is a little tricky. The kernel is not loaded at the correct 
+ * address, so the kernel must first be relocated, then copied, then
+ * jump back to the correct address.
+ */
+/* Copy routine */
+cps:
+2:     movb    (r0)+,(r1)+
+       cmpl    r0,r7
+       bneq    2b
+
+3:     clrb    (r1)+
+       incl    r0
+       cmpl    r0,r6
+       bneq    3b
+       clrl    -(sp)
+       movl    sp,ap
+       movl    $_cca,r7
+       movl    r8,(r7)
+       movpsl  -(sp)
+       pushl   r2
+       rei
+cpe:
+
+/* Copy the copy routine */
+1:     movab   cps,r0
+       movab   cpe,r1
+       movl    $0x300000,sp
+       movl    sp,r3
+4:     movb    (r0)+,(r3)+
+       cmpl    r0,r1
+       bneq    4b
+       movl    r7,r8
+/* Ok, copy routine copied, set registers and rei */
+       movab   _edata,r7
+       movab   _end,r6
+       movl    $0x80000000,r1
+       movl    $0x80000200,r0
+       subl3   $0x200,r6,r9
+       movab   2f,r2
+       subl2   $0x200,r2
+       movpsl  -(sp)
+       pushab  4(sp)
+       rei
+
 /*
  * First entry routine from boot. This should be in a file called locore.
  */
+JSBENTRY(start)
+       brb     1b                              # Netbooted starts here
+#else
 ASENTRY(start, 0)
-       bisl3   $0x80000000,r9,_esym            # End of loaded code
+#endif
+2:     bisl3   $0x80000000,r9,_esym            # End of loaded code
        pushl   $0x1f0000                       # Push a nice PSL
        pushl   $to                             # Address to jump to
        rei                                     # change to kernel stack