diff --git a/include/hw/s390x/sclp.h b/include/hw/s390x/sclp.h
index d3ade40a5a..712fd68123 100644
--- a/include/hw/s390x/sclp.h
+++ b/include/hw/s390x/sclp.h
@@ -112,6 +112,7 @@ typedef struct CPUEntry {
} QEMU_PACKED CPUEntry;
#define SCLP_READ_SCP_INFO_FIXED_CPU_OFFSET 128
+#define SCLP_READ_SCP_INFO_MNEST 2
typedef struct ReadInfo {
SCCBHeader h;
uint16_t rnmax;
diff --git a/target/s390x/cpu.h b/target/s390x/cpu.h
index d654267a71..e1f6925856 100644
--- a/target/s390x/cpu.h
+++ b/target/s390x/cpu.h
@@ -560,6 +560,25 @@ typedef struct SysIB_322 {
} SysIB_322;
QEMU_BUILD_BUG_ON(sizeof(SysIB_322) != 4096);
+#define S390_TOPOLOGY_MAG 6
+#define S390_TOPOLOGY_MAG6 0
+#define S390_TOPOLOGY_MAG5 1
+#define S390_TOPOLOGY_MAG4 2
+#define S390_TOPOLOGY_MAG3 3
+#define S390_TOPOLOGY_MAG2 4
+#define S390_TOPOLOGY_MAG1 5
+/* Configuration topology */
+typedef struct SysIB_151x {
+ uint8_t reserved0[2];
+ uint16_t length;
+ uint8_t mag[S390_TOPOLOGY_MAG];
+ uint8_t reserved1;
+ uint8_t mnest;
+ uint32_t reserved2;
+ char tle[];
+} QEMU_PACKED QEMU_ALIGNED(8) SysIB_151x;
+QEMU_BUILD_BUG_ON(sizeof(SysIB_151x) != 16);
+
typedef union SysIB {
SysIB_111 sysib_111;
SysIB_121 sysib_121;
@@ -567,9 +586,62 @@ typedef union SysIB {
SysIB_221 sysib_221;
SysIB_222 sysib_222;
SysIB_322 sysib_322;
+ SysIB_151x sysib_151x;
} SysIB;
QEMU_BUILD_BUG_ON(sizeof(SysIB) != 4096);
+/*
+ * CPU Topology List provided by STSI with fc=15 provides a list
+ * of two different Topology List Entries (TLE) types to specify
+ * the topology hierarchy.
+ *
+ * - Container Topology List Entry
+ * Defines a container to contain other Topology List Entries
+ * of any type, nested containers or CPU.
+ * - CPU Topology List Entry
+ * Specifies the CPUs position, type, entitlement and polarization
+ * of the CPUs contained in the last Container TLE.
+ *
+ * There can be theoretically up to five levels of containers, QEMU
+ * uses only three levels, the drawer's, book's and socket's level.
+ *
+ * A container of with a nesting level (NL) greater than 1 can only
+ * contain another container of nesting level NL-1.
+ *
+ * A container of nesting level 1 (socket), contains as many CPU TLE
+ * as needed to describe the position and qualities of all CPUs inside
+ * the container.
+ * The qualities of a CPU are polarization, entitlement and type.
+ *
+ * The CPU TLE defines the position of the CPUs of identical qualities
+ * using a 64bits mask which first bit has its offset defined by
+ * the CPU address orgin field of the CPU TLE like in:
+ * CPU address = origin * 64 + bit position within the mask
+ *
+ */
+/* Container type Topology List Entry */
+typedef struct SysIBTl_container {
+ uint8_t nl;
+ uint8_t reserved[6];
+ uint8_t id;
+} QEMU_PACKED QEMU_ALIGNED(8) SysIBTl_container;
+QEMU_BUILD_BUG_ON(sizeof(SysIBTl_container) != 8);
+
+/* CPU type Topology List Entry */
+typedef struct SysIBTl_cpu {
+ uint8_t nl;
+ uint8_t reserved0[3];
+#define SYSIB_TLE_POLARITY_MASK 0x03
+#define SYSIB_TLE_DEDICATED 0x04
+ uint8_t entitlement;
+ uint8_t type;
+ uint16_t origin;
+ uint64_t mask;
+} QEMU_PACKED QEMU_ALIGNED(8) SysIBTl_cpu;
+QEMU_BUILD_BUG_ON(sizeof(SysIBTl_cpu) != 16);
+
+void insert_stsi_15_1_x(S390CPU *cpu, int sel2, __u64 addr, uint8_t ar);