[src/trunk]: src/sys/arch/landisk/landisk PR 51724 - landisk fails to reboot.

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

details:   https://anonhg.NetBSD.org/src/rev/66b7b8aea5fb
branches:  trunk
changeset: 349637:66b7b8aea5fb
user:      uwe <uwe%NetBSD.org@localhost>
date:      Sat Dec 17 01:32:22 2016 +0000

description:
PR 51724 - landisk fails to reboot.

machine_reset() - instead of trying to cause an invalid data access
that gcc will optimize away, just use "trapa" instruction.

G/c assignment to EXPEVT, it will be set by the actual reset.  That
assignment has been probably cargo-culted from cpu_reset() that
manually jumps to 0xa0000000 (the reset address) instead of triggering
a reset.

TODO: This code should be SuperH generic cpu_reset().

diffstat:

 sys/arch/landisk/landisk/machdep.c |  7 +++----
 1 files changed, 3 insertions(+), 4 deletions(-)

diffs (28 lines):

diff -r 21f3b362a210 -r 66b7b8aea5fb sys/arch/landisk/landisk/machdep.c
--- a/sys/arch/landisk/landisk/machdep.c        Sat Dec 17 01:10:38 2016 +0000
+++ b/sys/arch/landisk/landisk/machdep.c        Sat Dec 17 01:32:22 2016 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: machdep.c,v 1.19 2016/12/17 01:10:38 uwe Exp $ */
+/*     $NetBSD: machdep.c,v 1.20 2016/12/17 01:32:22 uwe Exp $ */
 
 /*-
  * Copyright (c) 1996, 1997, 1998 The NetBSD Foundation, Inc.
@@ -65,7 +65,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: machdep.c,v 1.19 2016/12/17 01:10:38 uwe Exp $");
+__KERNEL_RCSID(0, "$NetBSD: machdep.c,v 1.20 2016/12/17 01:32:22 uwe Exp $");
 
 #include "opt_ddb.h"
 #include "opt_kgdb.h"
@@ -375,8 +375,7 @@
 {
 
        _cpu_exception_suspend();
-       _reg_write_4(SH_(EXPEVT), EXPEVT_RESET_MANUAL);
-       (void)*(volatile uint32_t *)0x80000001; /* CPU shutdown */
+       asm("trapa #0");
 
        /*NOTREACHED*/
        for (;;) {