From: Hans-Joachim Picht <hpicht@redhat.com>
Date: Tue, 22 Sep 2009 22:12:44 +0200
Subject: [s390] set preferred s390 console based on conmode
Message-id: 20090922201244.GB32244@blc4eb509856389.ibm.com
O-Subject: [RHEL5 U5 PATCH 1/1] s390 - kernel: set preferred s390 console based on conmode
Bugzilla: 520461
RH-Acked-by: Pete Zaitcev <zaitcev@redhat.com>

Description
============
setup_arch() unconditionally sets the preferred console to ttyS.
This breaks the use of 3270 devices as the console for displaying
kernel messages.

Provide a new function to set the default preferred console for s390:
The preferred console depends on the conmode parameter that is used
to switch between 3270 and 3215 terminal/console mode.

Bugzilla
=========

BZ 520461
https://bugzilla.redhat.com/show_bug.cgi?id=520461

Upstream status of the patch:
=============================

The patch is upstream as of kernel version 2.6.31

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=637952ca689013339b977558061fa4ca8e07e1c1

Test status:
============

The patch has been tested and fixes the problem.
The fix has been verified by the IBM test department.

Please ACK.

With best regards,

	Hans

diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index bf01463..f74b846 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -200,6 +200,14 @@ static int __init condev_setup(char *str)
 
 __setup("condev=", condev_setup);
 
+static void __init set_preferred_console(void)
+{
+	if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
+		add_preferred_console("ttyS", 0, NULL);
+	if (CONSOLE_IS_3270)
+		add_preferred_console("tty3270", 0, NULL);
+}
+
 static int __init conmode_setup(char *str)
 {
 #if defined(CONFIG_SCLP_CONSOLE)
@@ -214,6 +222,7 @@ static int __init conmode_setup(char *str)
 	if (strncmp(str, "3270", 5) == 0)
 		SET_CONSOLE_3270;
 #endif
+	set_preferred_console();
         return 1;
 }
 
@@ -896,9 +905,6 @@ static void __init setup_hwcaps(void)
 void __init
 setup_arch(char **cmdline_p)
 {
-	/* set up preferred console */
-	add_preferred_console("ttyS", 0, NULL);
-
         /*
          * print what head.S has found out about the machine
          */
@@ -961,6 +967,7 @@ setup_arch(char **cmdline_p)
 
         /* Setup default console */
 	conmode_default();
+	set_preferred_console();
 
 	/* Setup zfcpdump support */
 	setup_zfcpdump(console_devno);