xen/arm: allow console=hvc0 to be omitted for guests
From: Ard Biesheuvel <ard.biesheuvel@linaro.org>
This patch registers hvc0 as the preferred console if no console
has been specified explicitly on the kernel command line.
The purpose is to allow platform agnostic kernels and boot images
(such as distro installers) to boot in a Xen/ARM domU without the
need to modify the command line by hand.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Julien Grall <julien.grall@linaro.org>
diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c
index 3463a9e..6c09cc4 100644
--- a/arch/arm/xen/enlighten.c
+++ b/arch/arm/xen/enlighten.c
@@ -24,6 +24,7 @@
#include <linux/cpuidle.h>
#include <linux/cpufreq.h>
#include <linux/cpu.h>
+#include <linux/console.h>
#include <linux/mm.h>
@@ -183,6 +184,9 @@
xen_start_info->flags |= SIF_INITDOMAIN|SIF_PRIVILEGED;
else
xen_start_info->flags &= ~(SIF_INITDOMAIN|SIF_PRIVILEGED);
+
+ if (!console_set_on_cmdline && !xen_initial_domain())
+ add_preferred_console("hvc", 0, NULL);
}
static int __init xen_guest_init(void)