s390-bios: decouple cio setup from virtio

Move channel i/o setup code out to a separate function. This decouples cio
setup from the virtio code path and allows us to make use of it for booting
dasd devices.

Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
Acked-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Collin Walling <walling@linux.ibm.com>
Reviewed-by: Farhan Ali <alifm@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <1554388475-18329-3-git-send-email-jjherne@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

1 files changed, 13 insertions, 7 deletions

diff --git a/pc-bios/s390-ccw/main.c b/pc-bios/s390-ccw/main.c
index 544851d672..e82fe2ce23 100644
--- a/pc-bios/s390-ccw/main.c
+++ b/pc-bios/s390-ccw/main.c
@@ -99,6 +99,18 @@ static void menu_setup(void)
     }
 }
 
+/*
+ * Initialize the channel I/O subsystem so we can talk to our ipl/boot device.
+ */
+static void css_setup(void)
+{
+    /*
+     * Unconditionally enable mss support. In every sane configuration this
+     * will succeed; and even if it doesn't, stsch_err() can handle it.
+     */
+    enable_mss_facility();
+}
+
 static void virtio_setup(void)
 {
     Schib schib;
@@ -109,13 +121,6 @@ static void virtio_setup(void)
     VDev *vdev = virtio_get_device();
     QemuIplParameters *early_qipl = (QemuIplParameters *)QIPL_ADDRESS;
 
-    /*
-     * We unconditionally enable mss support. In every sane configuration,
-     * this will succeed; and even if it doesn't, stsch_err() can deal
-     * with the consequences.
-     */
-    enable_mss_facility();
-
     sclp_get_loadparm_ascii(loadparm_str);
     memcpy(ldp + 10, loadparm_str, LOADPARM_LEN);
     sclp_print(ldp);
@@ -168,6 +173,7 @@ static void virtio_setup(void)
 int main(void)
 {
     sclp_setup();
+    css_setup();
     virtio_setup();
 
     zipl_load(); /* no return */