s390x/sclp: reporting the maximum nested topology entries

The maximum nested topology entries is used by the guest to
know how many nested topology are available on the machine.

Let change the MNEST value from 2 to 4 in the SCLP READ INFO
structure now that we support books and drawers.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-ID: <20231016183925.2384704-6-nsg@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

diff --git a/hw/s390x/sclp.c b/hw/s390x/sclp.c
index eff74479f458788f0b37becde8dcfe690b398673..d339cbb7e403dfe6b89cd6df8d4ef2e037b7da35 100644 (file)
--- a/hw/s390x/sclp.c
+++ b/hw/s390x/sclp.c
@@ -20,6 +20,7 @@
 #include "hw/s390x/event-facility.h"
 #include "hw/s390x/s390-pci-bus.h"
 #include "hw/s390x/ipl.h"
+#include "hw/s390x/cpu-topology.h"
 
 static inline SCLPDevice *get_sclp_device(void)
 {
@@ -123,6 +124,10 @@ static void read_SCP_info(SCLPDevice *sclp, SCCB *sccb)
         return;
     }
 
+    if (s390_has_topology()) {
+        read_info->stsi_parm = SCLP_READ_SCP_INFO_MNEST;
+    }
+
     /* CPU information */
     prepare_cpu_entries(machine, entries_start, &cpu_count);
     read_info->entries_cpu = cpu_to_be16(cpu_count);

diff --git a/include/hw/s390x/sclp.h b/include/hw/s390x/sclp.h
index c49051e17ea4ee12e9be080555f0fa4aff49330a..9aef6d9370126fcbfb9e2f07bcec1fc6046f508f 100644 (file)
--- a/include/hw/s390x/sclp.h
+++ b/include/hw/s390x/sclp.h
@@ -112,12 +112,13 @@ typedef struct CPUEntry {
 } QEMU_PACKED CPUEntry;
 
 #define SCLP_READ_SCP_INFO_FIXED_CPU_OFFSET     128
-#define SCLP_READ_SCP_INFO_MNEST                2
+#define SCLP_READ_SCP_INFO_MNEST                4
 typedef struct ReadInfo {
     SCCBHeader h;
     uint16_t rnmax;
     uint8_t rnsize;
-    uint8_t  _reserved1[16 - 11];       /* 11-15 */
+    uint8_t  _reserved1[15 - 11];       /* 11-14 */
+    uint8_t stsi_parm;                  /* 15-15 */
     uint16_t entries_cpu;               /* 16-17 */
     uint16_t offset_cpu;                /* 18-19 */
     uint8_t  _reserved2[24 - 20];       /* 20-23 */