From patchwork Tue Apr 23 11:23:02 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Borntraeger X-Patchwork-Id: 238888 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id B07E12C0159 for ; Tue, 23 Apr 2013 21:23:29 +1000 (EST) Received: from localhost ([::1]:56986 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UUbJn-00006J-TW for incoming@patchwork.ozlabs.org; Tue, 23 Apr 2013 07:23:27 -0400 Received: from eggs.gnu.org ([208.118.235.92]:49431) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UUbJL-0008Ve-DM for qemu-devel@nongnu.org; Tue, 23 Apr 2013 07:23:01 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UUbJH-0000b5-Dj for qemu-devel@nongnu.org; Tue, 23 Apr 2013 07:22:59 -0400 Received: from e06smtp17.uk.ibm.com ([195.75.94.113]:55205) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UUbJH-0000af-5K for qemu-devel@nongnu.org; Tue, 23 Apr 2013 07:22:55 -0400 Received: from /spool/local by e06smtp17.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Lets stop the guest with a disabled wait. Signed-off-by: Christian Borntraeger --- pc-bios/s390-ccw/main.c | 2 ++ pc-bios/s390-ccw/s390-ccw.h | 3 +++ pc-bios/s390-ccw/start.S | 15 +++++++++++++++ 3 files changed, 20 insertions(+) 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 @@ char stack[PAGE_SIZE * 8] __attribute__((__aligned__(PAGE_SIZE))); void virtio_panic(const char *string) { sclp_print(string); + disabled_wait(); while (1) { } } @@ -52,5 +53,6 @@ int main(void) 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 @@ typedef unsigned long long __u64; #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 + * 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 @@ _start: 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