From: Jason J. Herne <jjherne@linux.ibm.com>
Date: Thu, 4 Apr 2019 14:34:32 +0000 (-0400)
Subject: s390-bios: Use control unit type to determine boot method
X-Git-Tag: v4.1.0-rc0~148^2^2~4
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=3668cb7ce864ee9351d5d20a1ec6b427cd0b3be4;p=thirdparty%2Fqemu.git

s390-bios: Use control unit type to determine boot method

The boot method is different depending on which device type we are
booting from. Let's examine the control unit type to determine if we're
a virtio device. We'll eventually add a case to check for a real dasd device
here as well.

Since we have to call enable_subchannel() in main now, might as well
remove that call from virtio.c : run_ccw(). This requires adding some
additional enable_subchannel calls to not break calls to
virtio_is_supported().

Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <1554388475-18329-14-git-send-email-jjherne@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
---

diff --git a/pc-bios/s390-ccw/main.c b/pc-bios/s390-ccw/main.c
index d3a161c6854..57a10138c65 100644
--- a/pc-bios/s390-ccw/main.c
+++ b/pc-bios/s390-ccw/main.c
@@ -76,6 +76,7 @@ static bool find_subch(int dev_no)
         /* Skip net devices since no IPLB is created and therefore no
          * network bootloader has been loaded
          */
+        enable_subchannel(blk_schid);
         if (virtio_is_supported(blk_schid) &&
             virtio_get_device_type() == VIRTIO_ID_NET && dev_no < 0) {
             continue;
@@ -198,13 +199,24 @@ static void virtio_setup(void)
 
 int main(void)
 {
+    uint16_t cutype;
+
     sclp_setup();
     css_setup();
     boot_setup();
     find_boot_device();
+    enable_subchannel(blk_schid);
 
-    virtio_setup();
-    zipl_load(); /* no return */
+    cutype = cu_type(blk_schid);
+    switch (cutype) {
+    case CU_TYPE_VIRTIO:
+        virtio_setup();
+        zipl_load(); /* no return */
+        break;
+    default:
+        print_int("Attempting to boot from unexpected device type", cutype);
+        panic("");
+    }
 
     panic("Failed to load OS from hard disk\n");
     return 0; /* make compiler happy */
diff --git a/pc-bios/s390-ccw/netmain.c b/pc-bios/s390-ccw/netmain.c
index 5189c0fc39e..f3542cb2cf1 100644
--- a/pc-bios/s390-ccw/netmain.c
+++ b/pc-bios/s390-ccw/netmain.c
@@ -476,6 +476,7 @@ static bool find_net_dev(Schib *schib, int dev_no)
         if (!schib->pmcw.dnv) {
             continue;
         }
+        enable_subchannel(net_schid);
         if (!virtio_is_supported(net_schid)) {
             continue;
         }
diff --git a/pc-bios/s390-ccw/virtio.c b/pc-bios/s390-ccw/virtio.c
index 35278eaee13..fb40ca98285 100644
--- a/pc-bios/s390-ccw/virtio.c
+++ b/pc-bios/s390-ccw/virtio.c
@@ -102,7 +102,6 @@ static int run_ccw(VDev *vdev, int cmd, void *ptr, int len, bool sli)
         ccw.flags |= CCW_FLAG_SLI;
     }
 
-    enable_subchannel(vdev->schid);
     return do_cio(vdev->schid, vdev->senseid.cu_type, ptr2u32(&ccw), CCW_FMT1);
 }