s390-ccw.img: replace while loop with a disabled wait on s390 bios
dont waste cpu power on an error condition. Lets stop the guest
with a disabled wait.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/pc-bios/s390-ccw/main.c b/pc-bios/s390-ccw/main.c
index 0913aac..67f4987 100644
--- a/pc-bios/s390-ccw/main.c
+++ b/pc-bios/s390-ccw/main.c
@@ -16,6 +16,7 @@
void virtio_panic(const char *string)
{
sclp_print(string);
+ disabled_wait();
while (1) { }
}
@@ -52,5 +53,6 @@
virtio_setup();
if (zipl_load() < 0)
sclp_print("Failed to load OS from hard disk\n");
+ disabled_wait();
while (1) { }
}
diff --git a/pc-bios/s390-ccw/s390-ccw.h b/pc-bios/s390-ccw/s390-ccw.h
index a03dbaf..8241b0a 100644
--- a/pc-bios/s390-ccw/s390-ccw.h
+++ b/pc-bios/s390-ccw/s390-ccw.h
@@ -45,6 +45,9 @@
#include "cio.h"
+/* start.s */
+void disabled_wait(void);
+
/* main.c */
void virtio_panic(const char *string);
diff --git a/pc-bios/s390-ccw/start.S b/pc-bios/s390-ccw/start.S
index c2b9a19..09deee7 100644
--- a/pc-bios/s390-ccw/start.S
+++ b/pc-bios/s390-ccw/start.S
@@ -3,6 +3,7 @@
* into the pc-bios directory of qemu.
*
* Copyright (c) 2013 Alexander Graf <agraf@suse.de>
+ * Copyright 2013 IBM Corp.
*
* This work is licensed under the terms of the GNU GPL, version 2 or (at
* your option) any later version. See the COPYING file in the top-level
@@ -14,3 +15,17 @@
larl %r15, stack + 0x8000 /* Set up stack */
j main /* And call C */
+
+/*
+ * void disabled_wait(void)
+ *
+ * stops the current guest cpu.
+ */
+ .globl disabled_wait
+disabled_wait:
+ larl %r1,disabled_wait_psw
+ lpswe 0(%r1)
+
+ .align 8
+disabled_wait_psw:
+ .quad 0x0002000180000000,0x0000000000000000
