powerpc: add PVR mask support

IBM POWERPC processors encode PVR as a CPU family in higher 16 bits and
a CPU version in lower 16 bits. Since there is no significant change
in behavior between versions, there is no point to add every single CPU
version in QEMU's CPU list. Also, new CPU versions of already supported
CPU won't break the existing code.

This adds PVR value/mask support for KVM, i.e. for -cpu host option.

As CPU family class name for POWER7 is "POWER7-family", there is no need
to touch aliases.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Alexander Graf <agraf@suse.de>

target-ppc/cpu-models.c

@@ -44,6 +44,7 @@
         PowerPCCPUClass *pcc = POWERPC_CPU_CLASS(oc);                       \
                                                                             \
         pcc->pvr          = _pvr;                                           \
+        pcc->pvr_mask     = CPU_POWERPC_DEFAULT_MASK;                       \
         pcc->svr          = _svr;                                           \
         dc->desc          = _desc;                                          \
     }                                                                       \

target-ppc/cpu-models.h

@@ -39,6 +39,7 @@ extern PowerPCCPUAlias ppc_cpu_aliases[];
 /*****************************************************************************/
 /* PVR definitions for most known PowerPC                                    */
 enum {
+    CPU_POWERPC_DEFAULT_MASK       = 0xFFFFFFFF,
     /* PowerPC 401 family */
     /* Generic PowerPC 401 */
 #define CPU_POWERPC_401              CPU_POWERPC_401G2
@@ -552,10 +553,14 @@ enum {
     CPU_POWERPC_POWER6             = 0x003E0000,
     CPU_POWERPC_POWER6_5           = 0x0F000001, /* POWER6 in POWER5 mode */
     CPU_POWERPC_POWER6A            = 0x0F000002,
+    CPU_POWERPC_POWER7_BASE        = 0x003F0000,
+    CPU_POWERPC_POWER7_MASK        = 0xFFFF0000,
     CPU_POWERPC_POWER7_v20         = 0x003F0200,
     CPU_POWERPC_POWER7_v21         = 0x003F0201,
     CPU_POWERPC_POWER7_v23         = 0x003F0203,
     CPU_POWERPC_POWER7P_v21        = 0x004A0201,
+    CPU_POWERPC_POWER8_BASE        = 0x004B0000,
+    CPU_POWERPC_POWER8_MASK        = 0xFFFF0000,
     CPU_POWERPC_POWER8_v10         = 0x004B0100,
     CPU_POWERPC_970                = 0x00390202,
     CPU_POWERPC_970FX_v10          = 0x00391100,

target-ppc/cpu-qom.h

@@ -54,6 +54,7 @@ typedef struct PowerPCCPUClass {
     void (*parent_reset)(CPUState *cpu);
 
     uint32_t pvr;
+    uint32_t pvr_mask;
     uint32_t svr;
     uint64_t insns_flags;
     uint64_t insns_flags2;
@@ -99,6 +100,7 @@ static inline PowerPCCPU *ppc_env_get_cpu(CPUPPCState *env)
 #define ENV_OFFSET offsetof(PowerPCCPU, env)
 
 PowerPCCPUClass *ppc_cpu_class_by_pvr(uint32_t pvr);
+PowerPCCPUClass *ppc_cpu_class_by_pvr_mask(uint32_t pvr);
 
 void ppc_cpu_do_interrupt(CPUState *cpu);
 void ppc_cpu_dump_state(CPUState *cpu, FILE *f, fprintf_function cpu_fprintf,

target-ppc/kvm.c

@@ -1745,6 +1745,7 @@ static void kvmppc_host_cpu_class_init(ObjectClass *oc, void *data)
     uint32_t icache_size = kvmppc_read_int_cpu_dt("i-cache-size");
 
     /* Now fix up the class with information we can query from the host */
+    pcc->pvr = mfpvr();
 
     if (vmx != -1) {
         /* Only override when we know what the host supports */
@@ -1794,6 +1795,9 @@ static int kvm_ppc_register_host_cpu_type(void)
     PowerPCCPUClass *pvr_pcc;
 
     pvr_pcc = ppc_cpu_class_by_pvr(host_pvr);
+    if (pvr_pcc == NULL) {
+        pvr_pcc = ppc_cpu_class_by_pvr_mask(host_pvr);
+    }
     if (pvr_pcc == NULL) {
         return -1;
     }

target-ppc/translate_init.c

@@ -7221,6 +7221,8 @@ POWERPC_FAMILY(POWER7)(ObjectClass *oc, void *data)
 
     dc->fw_name = "PowerPC,POWER7";
     dc->desc = "POWER7";
+    pcc->pvr = CPU_POWERPC_POWER7_BASE;
+    pcc->pvr_mask = CPU_POWERPC_POWER7_MASK;
     pcc->init_proc = init_proc_POWER7;
     pcc->check_pow = check_pow_nocheck;
     pcc->insns_flags = PPC_INSNS_BASE | PPC_ISEL | PPC_STRING | PPC_MFTB |
@@ -7256,6 +7258,8 @@ POWERPC_FAMILY(POWER8)(ObjectClass *oc, void *data)
 
     dc->fw_name = "PowerPC,POWER8";
     dc->desc = "POWER8";
+    pcc->pvr = CPU_POWERPC_POWER8_BASE;
+    pcc->pvr_mask = CPU_POWERPC_POWER8_MASK;
     pcc->init_proc = init_proc_POWER7;
     pcc->check_pow = check_pow_nocheck;
     pcc->insns_flags = PPC_INSNS_BASE | PPC_STRING | PPC_MFTB |
@@ -8188,6 +8192,44 @@ PowerPCCPUClass *ppc_cpu_class_by_pvr(uint32_t pvr)
     return pcc;
 }
 
+static gint ppc_cpu_compare_class_pvr_mask(gconstpointer a, gconstpointer b)
+{
+    ObjectClass *oc = (ObjectClass *)a;
+    uint32_t pvr = *(uint32_t *)b;
+    PowerPCCPUClass *pcc = (PowerPCCPUClass *)a;
+    gint ret;
+
+    /* -cpu host does a PVR lookup during construction */
+    if (unlikely(strcmp(object_class_get_name(oc),
+                        TYPE_HOST_POWERPC_CPU) == 0)) {
+        return -1;
+    }
+
+#if defined(TARGET_PPCEMB)
+    if (pcc->mmu_model != POWERPC_MMU_BOOKE) {
+        return -1;
+    }
+#endif
+    ret = (((pcc->pvr & pcc->pvr_mask) == (pvr & pcc->pvr_mask)) ? 0 : -1);
+
+    return ret;
+}
+
+PowerPCCPUClass *ppc_cpu_class_by_pvr_mask(uint32_t pvr)
+{
+    GSList *list, *item;
+    PowerPCCPUClass *pcc = NULL;
+
+    list = object_class_get_list(TYPE_POWERPC_CPU, true);
+    item = g_slist_find_custom(list, &pvr, ppc_cpu_compare_class_pvr_mask);
+    if (item != NULL) {
+        pcc = POWERPC_CPU_CLASS(item->data);
+    }
+    g_slist_free(list);
+
+    return pcc;
+}
+
 static gint ppc_cpu_compare_class_name(gconstpointer a, gconstpointer b)
 {
     ObjectClass *oc = (ObjectClass *)a;
@@ -8559,6 +8601,8 @@ static void ppc_cpu_class_init(ObjectClass *oc, void *data)
     DeviceClass *dc = DEVICE_CLASS(oc);
 
     pcc->parent_realize = dc->realize;
+    pcc->pvr = CPU_POWERPC_DEFAULT_MASK;
+    pcc->pvr_mask = CPU_POWERPC_DEFAULT_MASK;
     dc->realize = ppc_cpu_realizefn;
     dc->unrealize = ppc_cpu_unrealizefn;