s390x/ipl: Provide ipl parameter block

Right now we return the ipl parameter block only if the guest
specified one. Let's fill in the parameter block when bootindex
parameter is available and not booting from an external kernel.
Signed-off-by: NAlexander Yarygin <yarygin@linux.vnet.ibm.com>
Reviewed-by: NDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: NCornelia Huck <cornelia.huck@de.ibm.com>

hw/s390x/ipl.c

@@ -238,6 +238,12 @@ static uint64_t s390_update_iplstate(S390IPLState *ipl)
             ipl->cssid = ccw_dev->sch->cssid;
             ipl->ssid = ccw_dev->sch->ssid;
             ipl->devno = ccw_dev->sch->devno;
+            ipl->iplb.len = cpu_to_be32(S390_IPLB_MIN_CCW_LEN);
+            ipl->iplb.blk0_len =
+                cpu_to_be32(S390_IPLB_MIN_CCW_LEN - S390_IPLB_HEADER_LEN);
+            ipl->iplb.pbt = S390_IPL_TYPE_CCW;
+            ipl->iplb.ccw.devno = cpu_to_be16(ccw_dev->sch->devno);
+            ipl->iplb_valid = true;
             goto out;
         }
     }
@@ -292,6 +298,7 @@ static void s390_ipl_reset(DeviceState *dev)
 
     if (!ipl->reipl_requested) {
         ipl->iplb_valid = false;
+        memset(&ipl->iplb, 0, sizeof(IplParameterBlock));
     }
     ipl->reipl_requested = false;
 }

hw/s390x/ipl.h

@@ -102,6 +102,7 @@ typedef struct S390IPLState S390IPLState;
 #define S390_IPL_TYPE_FCP 0x00
 #define S390_IPL_TYPE_CCW 0x02
 
+#define S390_IPLB_HEADER_LEN 8
 #define S390_IPLB_MIN_CCW_LEN 200
 #define S390_IPLB_MIN_FCP_LEN 384