diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h
index 7b52a9bb18..417b284318 100644
--- a/target/ppc/cpu.h
+++ b/target/ppc/cpu.h
@@ -1512,6 +1512,17 @@ struct PowerPCCPUClass {
     int  (*check_attn)(CPUPPCState *env);
 };
 
+static inline bool ppc_cpu_core_single_threaded(CPUState *cs)
+{
+    return cs->nr_threads == 1;
+}
+
+static inline bool ppc_cpu_lpar_single_threaded(CPUState *cs)
+{
+    return !(POWERPC_CPU(cs)->env.flags & POWERPC_FLAG_SMT_1LPAR) ||
+           ppc_cpu_core_single_threaded(cs);
+}
+
 ObjectClass *ppc_cpu_class_by_name(const char *name);
 PowerPCCPUClass *ppc_cpu_class_by_pvr(uint32_t pvr);
 PowerPCCPUClass *ppc_cpu_class_by_pvr_mask(uint32_t pvr);
diff --git a/target/ppc/cpu_init.c b/target/ppc/cpu_init.c
index 164bb62e63..81dd4e1a7a 100644
--- a/target/ppc/cpu_init.c
+++ b/target/ppc/cpu_init.c
@@ -6993,7 +6993,7 @@ static void ppc_cpu_realize(DeviceState *dev, Error **errp)
 
     pcc->parent_realize(dev, errp);
 
-    if (env_cpu(env)->nr_threads > 1) {
+    if (!ppc_cpu_core_single_threaded(cs)) {
         env->flags |= POWERPC_FLAG_SMT;
     }
 
diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c
index 5368bf2ff3..5ecd662f9e 100644
--- a/target/ppc/excp_helper.c
+++ b/target/ppc/excp_helper.c
@@ -3014,18 +3014,11 @@ static void msgsnd_core_tir(CPUPPCState *env, uint32_t target_tir, int irq)
 {
     PowerPCCPU *cpu = env_archcpu(env);
     CPUState *cs = env_cpu(env);
-    uint32_t nr_threads = cs->nr_threads;
 
-    if (!(env->flags & POWERPC_FLAG_SMT_1LPAR)) {
-        nr_threads = 1; /* msgsndp behaves as 1-thread in LPAR-per-thread mode*/
-    }
-
-    if (target_tir >= nr_threads) {
-        return;
-    }
-
-    if (nr_threads == 1) {
-        ppc_set_irq(cpu, irq, 1);
+    if (ppc_cpu_lpar_single_threaded(cs)) {
+        if (target_tir == 0) {
+            ppc_set_irq(cpu, irq, 1);
+        }
     } else {
         CPUState *ccs;
 
@@ -3080,7 +3073,7 @@ void helper_book3s_msgsnd(CPUPPCState *env, target_ulong rb)
         brdcast = true;
     }
 
-    if (cs->nr_threads == 1 || !brdcast) {
+    if (ppc_cpu_core_single_threaded(cs) || !brdcast) {
         ppc_set_irq(cpu, PPC_INTERRUPT_HDOORBELL, 1);
         return;
     }
diff --git a/target/ppc/misc_helper.c b/target/ppc/misc_helper.c
index 4d3c1bddd9..692e48e6bc 100644
--- a/target/ppc/misc_helper.c
+++ b/target/ppc/misc_helper.c
@@ -49,9 +49,8 @@ void helper_spr_core_write_generic(CPUPPCState *env, uint32_t sprn,
 {
     CPUState *cs = env_cpu(env);
     CPUState *ccs;
-    uint32_t nr_threads = cs->nr_threads;
 
-    if (nr_threads == 1) {
+    if (ppc_cpu_core_single_threaded(cs)) {
         env->spr[sprn] = val;
         return;
     }
@@ -196,7 +195,7 @@ void helper_store_ptcr(CPUPPCState *env, target_ulong val)
             return;
         }
 
-        if (cs->nr_threads == 1 || !(env->flags & POWERPC_FLAG_SMT_1LPAR)) {
+        if (ppc_cpu_lpar_single_threaded(cs)) {
             env->spr[SPR_PTCR] = val;
             tlb_flush(cs);
         } else {
@@ -243,16 +242,12 @@ target_ulong helper_load_dpdes(CPUPPCState *env)
 {
     CPUState *cs = env_cpu(env);
     CPUState *ccs;
-    uint32_t nr_threads = cs->nr_threads;
     target_ulong dpdes = 0;
 
     helper_hfscr_facility_check(env, HFSCR_MSGP, "load DPDES", HFSCR_IC_MSGP);
 
-    if (!(env->flags & POWERPC_FLAG_SMT_1LPAR)) {
-        nr_threads = 1; /* DPDES behaves as 1-thread in LPAR-per-thread mode */
-    }
-
-    if (nr_threads == 1) {
+    /* DPDES behaves as 1-thread in LPAR-per-thread mode */
+    if (ppc_cpu_lpar_single_threaded(cs)) {
         if (env->pending_interrupts & PPC_INTERRUPT_DOORBELL) {
             dpdes = 1;
         }
@@ -279,21 +274,11 @@ void helper_store_dpdes(CPUPPCState *env, target_ulong val)
     PowerPCCPU *cpu = env_archcpu(env);
     CPUState *cs = env_cpu(env);
     CPUState *ccs;
-    uint32_t nr_threads = cs->nr_threads;
 
     helper_hfscr_facility_check(env, HFSCR_MSGP, "store DPDES", HFSCR_IC_MSGP);
 
-    if (!(env->flags & POWERPC_FLAG_SMT_1LPAR)) {
-        nr_threads = 1; /* DPDES behaves as 1-thread in LPAR-per-thread mode */
-    }
-
-    if (val & ~(nr_threads - 1)) {
-        qemu_log_mask(LOG_GUEST_ERROR, "Invalid DPDES register value "
-                      TARGET_FMT_lx"\n", val);
-        val &= (nr_threads - 1); /* Ignore the invalid bits */
-    }
-
-    if (nr_threads == 1) {
+    /* DPDES behaves as 1-thread in LPAR-per-thread mode */
+    if (ppc_cpu_lpar_single_threaded(cs)) {
         ppc_set_irq(cpu, PPC_INTERRUPT_DOORBELL, val & 0x1);
         return;
     }
diff --git a/target/ppc/timebase_helper.c b/target/ppc/timebase_helper.c
index 52f9e6669c..44cacf065e 100644
--- a/target/ppc/timebase_helper.c
+++ b/target/ppc/timebase_helper.c
@@ -63,9 +63,8 @@ void helper_store_purr(CPUPPCState *env, target_ulong val)
 {
     CPUState *cs = env_cpu(env);
     CPUState *ccs;
-    uint32_t nr_threads = cs->nr_threads;
 
-    if (nr_threads == 1 || !(env->flags & POWERPC_FLAG_SMT_1LPAR)) {
+    if (ppc_cpu_lpar_single_threaded(cs)) {
         cpu_ppc_store_purr(env, val);
         return;
     }
@@ -82,9 +81,8 @@ void helper_store_tbl(CPUPPCState *env, target_ulong val)
 {
     CPUState *cs = env_cpu(env);
     CPUState *ccs;
-    uint32_t nr_threads = cs->nr_threads;
 
-    if (nr_threads == 1 || !(env->flags & POWERPC_FLAG_SMT_1LPAR)) {
+    if (ppc_cpu_lpar_single_threaded(cs)) {
         cpu_ppc_store_tbl(env, val);
         return;
     }
@@ -99,9 +97,8 @@ void helper_store_tbu(CPUPPCState *env, target_ulong val)
 {
     CPUState *cs = env_cpu(env);
     CPUState *ccs;
-    uint32_t nr_threads = cs->nr_threads;
 
-    if (nr_threads == 1 || !(env->flags & POWERPC_FLAG_SMT_1LPAR)) {
+    if (ppc_cpu_lpar_single_threaded(cs)) {
         cpu_ppc_store_tbu(env, val);
         return;
     }
@@ -141,9 +138,8 @@ void helper_store_hdecr(CPUPPCState *env, target_ulong val)
 {
     CPUState *cs = env_cpu(env);
     CPUState *ccs;
-    uint32_t nr_threads = cs->nr_threads;
 
-    if (nr_threads == 1 || !(env->flags & POWERPC_FLAG_SMT_1LPAR)) {
+    if (ppc_cpu_lpar_single_threaded(cs)) {
         cpu_ppc_store_hdecr(env, val);
         return;
     }
@@ -158,9 +154,8 @@ void helper_store_vtb(CPUPPCState *env, target_ulong val)
 {
     CPUState *cs = env_cpu(env);
     CPUState *ccs;
-    uint32_t nr_threads = cs->nr_threads;
 
-    if (nr_threads == 1 || !(env->flags & POWERPC_FLAG_SMT_1LPAR)) {
+    if (ppc_cpu_lpar_single_threaded(cs)) {
         cpu_ppc_store_vtb(env, val);
         return;
     }
@@ -175,9 +170,8 @@ void helper_store_tbu40(CPUPPCState *env, target_ulong val)
 {
     CPUState *cs = env_cpu(env);
     CPUState *ccs;
-    uint32_t nr_threads = cs->nr_threads;
 
-    if (nr_threads == 1 || !(env->flags & POWERPC_FLAG_SMT_1LPAR)) {
+    if (ppc_cpu_lpar_single_threaded(cs)) {
         cpu_ppc_store_tbu40(env, val);
         return;
     }
@@ -288,7 +282,7 @@ static void write_tfmr(CPUPPCState *env, target_ulong val)
 {
     CPUState *cs = env_cpu(env);
 
-    if (cs->nr_threads == 1) {
+    if (ppc_cpu_core_single_threaded(cs)) {
         env->spr[SPR_TFMR] = val;
     } else {
         CPUState *ccs;
