diff --git a/arch/powerpc/include/asm/opal.h b/arch/powerpc/include/asm/opal.h
index 3dea31c1080c..eb95b675109b 100644
--- a/arch/powerpc/include/asm/opal.h
+++ b/arch/powerpc/include/asm/opal.h
@@ -161,6 +161,7 @@ struct opal_sg_list {
 #define OPAL_PCI_EEH_FREEZE_SET			97
 #define OPAL_HANDLE_HMI				98
 #define OPAL_CONFIG_CPU_IDLE_STATE		99
+#define OPAL_SLW_SET_REG			100
 #define OPAL_REGISTER_DUMP_REGION		101
 #define OPAL_UNREGISTER_DUMP_REGION		102
 #define OPAL_WRITE_TPO				103
@@ -176,6 +177,7 @@ struct opal_sg_list {
  */
 #define OPAL_PM_NAP_ENABLED	0x00010000
 #define OPAL_PM_SLEEP_ENABLED	0x00020000
+#define OPAL_PM_WINKLE_ENABLED	0x00040000
 #define OPAL_PM_SLEEP_ENABLED_ER1	0x00080000
 
 #ifndef __ASSEMBLY__
@@ -913,6 +915,7 @@ int64_t opal_sensor_read(uint32_t sensor_hndl, int token, __be32 *sensor_data);
 int64_t opal_handle_hmi(void);
 int64_t opal_register_dump_region(uint32_t id, uint64_t start, uint64_t end);
 int64_t opal_unregister_dump_region(uint32_t id);
+int64_t opal_slw_set_reg(uint64_t cpu_pir, uint64_t sprn, uint64_t val);
 int64_t opal_pci_set_phb_cxl_mode(uint64_t phb_id, uint64_t mode, uint64_t pe_number);
 int64_t opal_ipmi_send(uint64_t interface, struct opal_ipmi_msg *msg,
 		uint64_t msg_len);
diff --git a/arch/powerpc/include/asm/paca.h b/arch/powerpc/include/asm/paca.h
index a0a16847bd40..e5f22c6c4bf9 100644
--- a/arch/powerpc/include/asm/paca.h
+++ b/arch/powerpc/include/asm/paca.h
@@ -158,6 +158,8 @@ struct paca_struct {
 	u8 thread_idle_state;		/* PNV_THREAD_RUNNING/NAP/SLEEP	*/
 	/* Mask to indicate thread id in core */
 	u8 thread_mask;
+	/* Mask to denote subcore sibling threads */
+	u8 subcore_sibling_mask;
 #endif
 
 #ifdef CONFIG_PPC_BOOK3S_64
diff --git a/arch/powerpc/include/asm/ppc-opcode.h b/arch/powerpc/include/asm/ppc-opcode.h
index 6f8536208049..5155be7c0d48 100644
--- a/arch/powerpc/include/asm/ppc-opcode.h
+++ b/arch/powerpc/include/asm/ppc-opcode.h
@@ -194,6 +194,7 @@
 
 #define PPC_INST_NAP			0x4c000364
 #define PPC_INST_SLEEP			0x4c0003a4
+#define PPC_INST_WINKLE			0x4c0003e4
 
 /* A2 specific instructions */
 #define PPC_INST_ERATWE			0x7c0001a6
@@ -374,6 +375,7 @@
 
 #define PPC_NAP			stringify_in_c(.long PPC_INST_NAP)
 #define PPC_SLEEP		stringify_in_c(.long PPC_INST_SLEEP)
+#define PPC_WINKLE		stringify_in_c(.long PPC_INST_WINKLE)
 
 /* BHRB instructions */
 #define PPC_CLRBHRB		stringify_in_c(.long PPC_INST_CLRBHRB)
diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h
index f5c45b37c0d4..bf117d8fb45f 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -453,6 +453,7 @@ enum idle_boot_override {IDLE_NO_OVERRIDE = 0, IDLE_POWERSAVE_OFF};
 extern int powersave_nap;	/* set if nap mode can be used in idle loop */
 extern unsigned long power7_nap(int check_irq);
 extern unsigned long power7_sleep(void);
+extern unsigned long power7_winkle(void);
 extern void flush_instruction_cache(void);
 extern void hard_reset_now(void);
 extern void poweroff_now(void);
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index a68ee15964b3..1c874fb533bb 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -373,6 +373,7 @@
 #define SPRN_DBAT7L	0x23F	/* Data BAT 7 Lower Register */
 #define SPRN_DBAT7U	0x23E	/* Data BAT 7 Upper Register */
 #define SPRN_PPR	0x380	/* SMT Thread status Register */
+#define SPRN_TSCR	0x399	/* Thread Switch Control Register */
 
 #define SPRN_DEC	0x016		/* Decrement Register */
 #define SPRN_DER	0x095		/* Debug Enable Regsiter */
@@ -730,6 +731,7 @@
 #define SPRN_BESCR	806	/* Branch event status and control register */
 #define   BESCR_GE	0x8000000000000000ULL /* Global Enable */
 #define SPRN_WORT	895	/* Workload optimization register - thread */
+#define SPRN_WORC	863	/* Workload optimization register - core */
 
 #define SPRN_PMC1	787
 #define SPRN_PMC2	788
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index bbd27fe0c039..f68de7a73faa 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -733,6 +733,8 @@ int main(void)
 			offsetof(struct paca_struct, thread_idle_state));
 	DEFINE(PACA_THREAD_MASK,
 			offsetof(struct paca_struct, thread_mask));
+	DEFINE(PACA_SUBCORE_SIBLING_MASK,
+			offsetof(struct paca_struct, subcore_sibling_mask));
 #endif
 
 	return 0;
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index 289fe718ecd4..c2df8150bd7a 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -102,9 +102,7 @@ system_reset_pSeries:
 #ifdef CONFIG_PPC_P7_NAP
 BEGIN_FTR_SECTION
 	/* Running native on arch 2.06 or later, check if we are
-	 * waking up from nap. We only handle no state loss and
-	 * supervisor state loss. We do -not- handle hypervisor
-	 * state loss at this time.
+	 * waking up from nap/sleep/winkle.
 	 */
 	mfspr	r13,SPRN_SRR1
 	rlwinm.	r13,r13,47-31,30,31
@@ -112,7 +110,16 @@ BEGIN_FTR_SECTION
 
 	cmpwi	cr3,r13,2
 
+	/*
+	 * Check if last bit of HSPGR0 is set. This indicates whether we are
+	 * waking up from winkle.
+	 */
 	GET_PACA(r13)
+	clrldi	r5,r13,63
+	clrrdi	r13,r13,1
+	cmpwi	cr4,r5,1
+	mtspr	SPRN_HSPRG0,r13
+
 	lbz	r0,PACA_THREAD_IDLE_STATE(r13)
 	cmpwi   cr2,r0,PNV_THREAD_NAP
 	bgt     cr2,8f				/* Either sleep or Winkle */
diff --git a/arch/powerpc/kernel/idle_power7.S b/arch/powerpc/kernel/idle_power7.S
index 0f2c113c8ca5..05adc8bbdef8 100644
--- a/arch/powerpc/kernel/idle_power7.S
+++ b/arch/powerpc/kernel/idle_power7.S
@@ -19,9 +19,24 @@
 #include <asm/kvm_book3s_asm.h>
 #include <asm/opal.h>
 #include <asm/cpuidle.h>
+#include <asm/mmu-hash64.h>
 
 #undef DEBUG
 
+/*
+ * Use unused space in the interrupt stack to save and restore
+ * registers for winkle support.
+ */
+#define _SDR1	GPR3
+#define _RPR	GPR4
+#define _SPURR	GPR5
+#define _PURR	GPR6
+#define _TSCR	GPR7
+#define _DSCR	GPR8
+#define _AMOR	GPR9
+#define _WORT	GPR10
+#define _WORC	GPR11
+
 /* Idle state entry routines */
 
 #define	IDLE_STATE_ENTER_SEQ(IDLE_INST)				\
@@ -124,8 +139,8 @@ power7_enter_nap_mode:
 	stb	r4,HSTATE_HWTHREAD_STATE(r13)
 #endif
 	stb	r3,PACA_THREAD_IDLE_STATE(r13)
-	cmpwi	cr1,r3,PNV_THREAD_SLEEP
-	bge	cr1,2f
+	cmpwi	cr3,r3,PNV_THREAD_SLEEP
+	bge	cr3,2f
 	IDLE_STATE_ENTER_SEQ(PPC_NAP)
 	/* No return */
 2:
@@ -154,7 +169,8 @@ pnv_fastsleep_workaround_at_entry:
 	bne-	lwarx_loop1
 	isync
 
-common_enter: /* common code for all the threads entering sleep */
+common_enter: /* common code for all the threads entering sleep or winkle */
+	bgt	cr3,enter_winkle
 	IDLE_STATE_ENTER_SEQ(PPC_SLEEP)
 
 fastsleep_workaround_at_entry:
@@ -175,6 +191,30 @@ fastsleep_workaround_at_entry:
 	stw	r0,0(r14)
 	b	common_enter
 
+enter_winkle:
+	/*
+	 * Note all register i.e per-core, per-subcore or per-thread is saved
+	 * here since any thread in the core might wake up first
+	 */
+	mfspr	r3,SPRN_SDR1
+	std	r3,_SDR1(r1)
+	mfspr	r3,SPRN_RPR
+	std	r3,_RPR(r1)
+	mfspr	r3,SPRN_SPURR
+	std	r3,_SPURR(r1)
+	mfspr	r3,SPRN_PURR
+	std	r3,_PURR(r1)
+	mfspr	r3,SPRN_TSCR
+	std	r3,_TSCR(r1)
+	mfspr	r3,SPRN_DSCR
+	std	r3,_DSCR(r1)
+	mfspr	r3,SPRN_AMOR
+	std	r3,_AMOR(r1)
+	mfspr	r3,SPRN_WORT
+	std	r3,_WORT(r1)
+	mfspr	r3,SPRN_WORC
+	std	r3,_WORC(r1)
+	IDLE_STATE_ENTER_SEQ(PPC_WINKLE)
 
 _GLOBAL(power7_idle)
 	/* Now check if user or arch enabled NAP mode */
@@ -197,6 +237,12 @@ _GLOBAL(power7_sleep)
 	b	power7_powersave_common
 	/* No return */
 
+_GLOBAL(power7_winkle)
+	li	r3,3
+	li	r4,1
+	b	power7_powersave_common
+	/* No return */
+
 #define CHECK_HMI_INTERRUPT						\
 	mfspr	r0,SPRN_SRR1;						\
 BEGIN_FTR_SECTION_NESTED(66);						\
@@ -250,11 +296,23 @@ lwarx_loop2:
 	bne	core_idle_lock_held
 
 	cmpwi	cr2,r15,0
+	lbz	r4,PACA_SUBCORE_SIBLING_MASK(r13)
+	and	r4,r4,r15
+	cmpwi	cr1,r4,0	/* Check if first in subcore */
+
+	/*
+	 * At this stage
+	 * cr1 - 0b0100 if first thread to wakeup in subcore
+	 * cr2 - 0b0100 if first thread to wakeup in core
+	 * cr3-  0b0010 if waking up from sleep or winkle
+	 * cr4 - 0b0100 if waking up from winkle
+	 */
+
 	or	r15,r15,r7		/* Set thread bit */
 
-	beq	cr2,first_thread
+	beq	cr1,first_thread_in_subcore
 
-	/* Not first thread in core to wake up */
+	/* Not first thread in subcore to wake up */
 	stwcx.	r15,0,r14
 	bne-	lwarx_loop2
 	isync
@@ -269,13 +327,36 @@ core_idle_lock_loop:
 	HMT_MEDIUM
 	b	lwarx_loop2
 
-first_thread:
-	/* First thread in core to wakeup */
+first_thread_in_subcore:
+	/* First thread in subcore to wakeup */
 	ori	r15,r15,PNV_CORE_IDLE_LOCK_BIT
 	stwcx.	r15,0,r14
 	bne-	lwarx_loop2
 	isync
 
+	/*
+	 * If waking up from sleep, subcore state is not lost. Hence
+	 * skip subcore state restore
+	 */
+	bne	cr4,subcore_state_restored
+
+	/* Restore per-subcore state */
+	ld      r4,_SDR1(r1)
+	mtspr   SPRN_SDR1,r4
+	ld      r4,_RPR(r1)
+	mtspr   SPRN_RPR,r4
+	ld	r4,_AMOR(r1)
+	mtspr	SPRN_AMOR,r4
+
+subcore_state_restored:
+	/*
+	 * Check if the thread is also the first thread in the core. If not,
+	 * skip to clear_lock.
+	 */
+	bne	cr2,clear_lock
+
+first_thread_in_core:
+
 	/*
 	 * First thread in the core waking up from fastsleep. It needs to
 	 * call the fastsleep workaround code if the platform requires it.
@@ -296,12 +377,62 @@ timebase_resync:
 	bl	opal_call_realmode;
 	/* TODO: Check r3 for failure */
 
+	/*
+	 * If waking up from sleep, per core state is not lost, skip to
+	 * clear_lock.
+	 */
+	bne	cr4,clear_lock
+
+	/* Restore per core state */
+	ld	r4,_TSCR(r1)
+	mtspr	SPRN_TSCR,r4
+	ld	r4,_WORC(r1)
+	mtspr	SPRN_WORC,r4
+
 clear_lock:
 	andi.	r15,r15,PNV_CORE_IDLE_THREAD_BITS
 	lwsync
 	stw	r15,0(r14)
 
 common_exit:
+	/*
+	 * Common to all threads.
+	 *
+	 * If waking up from sleep, hypervisor state is not lost. Hence
+	 * skip hypervisor state restore.
+	 */
+	bne	cr4,hypervisor_state_restored
+
+	/* Waking up from winkle */
+
+	/* Restore per thread state */
+	bl	__restore_cpu_power8
+
+	/* Restore SLB  from PACA */
+	ld	r8,PACA_SLBSHADOWPTR(r13)
+
+	.rept	SLB_NUM_BOLTED
+	li	r3, SLBSHADOW_SAVEAREA
+	LDX_BE	r5, r8, r3
+	addi	r3, r3, 8
+	LDX_BE	r6, r8, r3
+	andis.	r7,r5,SLB_ESID_V@h
+	beq	1f
+	slbmte	r6,r5
+1:	addi	r8,r8,16
+	.endr
+
+	ld	r4,_SPURR(r1)
+	mtspr	SPRN_SPURR,r4
+	ld	r4,_PURR(r1)
+	mtspr	SPRN_PURR,r4
+	ld	r4,_DSCR(r1)
+	mtspr	SPRN_DSCR,r4
+	ld	r4,_WORT(r1)
+	mtspr	SPRN_WORT,r4
+
+hypervisor_state_restored:
+
 	li	r5,PNV_THREAD_RUNNING
 	stb     r5,PACA_THREAD_IDLE_STATE(r13)
 
diff --git a/arch/powerpc/platforms/powernv/opal-wrappers.S b/arch/powerpc/platforms/powernv/opal-wrappers.S
index 78289ed7058c..54eca8b3b288 100644
--- a/arch/powerpc/platforms/powernv/opal-wrappers.S
+++ b/arch/powerpc/platforms/powernv/opal-wrappers.S
@@ -284,6 +284,7 @@ OPAL_CALL(opal_sensor_read,			OPAL_SENSOR_READ);
 OPAL_CALL(opal_get_param,			OPAL_GET_PARAM);
 OPAL_CALL(opal_set_param,			OPAL_SET_PARAM);
 OPAL_CALL(opal_handle_hmi,			OPAL_HANDLE_HMI);
+OPAL_CALL(opal_slw_set_reg,			OPAL_SLW_SET_REG);
 OPAL_CALL(opal_register_dump_region,		OPAL_REGISTER_DUMP_REGION);
 OPAL_CALL(opal_unregister_dump_region,		OPAL_UNREGISTER_DUMP_REGION);
 OPAL_CALL(opal_pci_set_phb_cxl_mode,		OPAL_PCI_SET_PHB_CXL_MODE);
diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c
index 2e9b53bb73e2..b700a329c31d 100644
--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -41,6 +41,7 @@
 #include <asm/code-patching.h>
 
 #include "powernv.h"
+#include "subcore.h"
 
 static void __init pnv_setup_arch(void)
 {
@@ -293,6 +294,72 @@ static void __init pnv_setup_machdep_rtas(void)
 
 static u32 supported_cpuidle_states;
 
+int pnv_save_sprs_for_winkle(void)
+{
+	int cpu;
+	int rc;
+
+	/*
+	 * hid0, hid1, hid4, hid5, hmeer and lpcr values are symmetric accross
+	 * all cpus at boot. Get these reg values of current cpu and use the
+	 * same accross all cpus.
+	 */
+	uint64_t lpcr_val = mfspr(SPRN_LPCR);
+	uint64_t hid0_val = mfspr(SPRN_HID0);
+	uint64_t hid1_val = mfspr(SPRN_HID1);
+	uint64_t hid4_val = mfspr(SPRN_HID4);
+	uint64_t hid5_val = mfspr(SPRN_HID5);
+	uint64_t hmeer_val = mfspr(SPRN_HMEER);
+
+	for_each_possible_cpu(cpu) {
+		uint64_t pir = get_hard_smp_processor_id(cpu);
+		uint64_t hsprg0_val = (uint64_t)&paca[cpu];
+
+		/*
+		 * HSPRG0 is used to store the cpu's pointer to paca. Hence last
+		 * 3 bits are guaranteed to be 0. Program slw to restore HSPRG0
+		 * with 63rd bit set, so that when a thread wakes up at 0x100 we
+		 * can use this bit to distinguish between fastsleep and
+		 * deep winkle.
+		 */
+		hsprg0_val |= 1;
+
+		rc = opal_slw_set_reg(pir, SPRN_HSPRG0, hsprg0_val);
+		if (rc != 0)
+			return rc;
+
+		rc = opal_slw_set_reg(pir, SPRN_LPCR, lpcr_val);
+		if (rc != 0)
+			return rc;
+
+		/* HIDs are per core registers */
+		if (cpu_thread_in_core(cpu) == 0) {
+
+			rc = opal_slw_set_reg(pir, SPRN_HMEER, hmeer_val);
+			if (rc != 0)
+				return rc;
+
+			rc = opal_slw_set_reg(pir, SPRN_HID0, hid0_val);
+			if (rc != 0)
+				return rc;
+
+			rc = opal_slw_set_reg(pir, SPRN_HID1, hid1_val);
+			if (rc != 0)
+				return rc;
+
+			rc = opal_slw_set_reg(pir, SPRN_HID4, hid4_val);
+			if (rc != 0)
+				return rc;
+
+			rc = opal_slw_set_reg(pir, SPRN_HID5, hid5_val);
+			if (rc != 0)
+				return rc;
+		}
+	}
+
+	return 0;
+}
+
 static void pnv_alloc_idle_core_states(void)
 {
 	int i, j;
@@ -325,6 +392,11 @@ static void pnv_alloc_idle_core_states(void)
 			paca[cpu].thread_mask = 1 << j;
 		}
 	}
+
+	update_subcore_sibling_mask();
+
+	if (supported_cpuidle_states & OPAL_PM_WINKLE_ENABLED)
+		pnv_save_sprs_for_winkle();
 }
 
 u32 pnv_get_supported_cpuidle_states(void)
diff --git a/arch/powerpc/platforms/powernv/smp.c b/arch/powerpc/platforms/powernv/smp.c
index c0691d0fb385..6c551a28e899 100644
--- a/arch/powerpc/platforms/powernv/smp.c
+++ b/arch/powerpc/platforms/powernv/smp.c
@@ -167,12 +167,17 @@ static void pnv_smp_cpu_kill_self(void)
 	 */
 	mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) & ~(u64)LPCR_PECE1);
 	while (!generic_check_cpu_restart(cpu)) {
+
 		ppc64_runlatch_off();
-		if ((idle_states & OPAL_PM_SLEEP_ENABLED) ||
+
+		if (idle_states & OPAL_PM_WINKLE_ENABLED)
+			srr1 = power7_winkle();
+		else if ((idle_states & OPAL_PM_SLEEP_ENABLED) ||
 				(idle_states & OPAL_PM_SLEEP_ENABLED_ER1))
 			srr1 = power7_sleep();
 		else
 			srr1 = power7_nap(1);
+
 		ppc64_runlatch_on();
 
 		/*
diff --git a/arch/powerpc/platforms/powernv/subcore.c b/arch/powerpc/platforms/powernv/subcore.c
index c87f96b79d1a..f60f80ada903 100644
--- a/arch/powerpc/platforms/powernv/subcore.c
+++ b/arch/powerpc/platforms/powernv/subcore.c
@@ -160,6 +160,18 @@ static void wait_for_sync_step(int step)
 	mb();
 }
 
+static void update_hid_in_slw(u64 hid0)
+{
+	u64 idle_states = pnv_get_supported_cpuidle_states();
+
+	if (idle_states & OPAL_PM_WINKLE_ENABLED) {
+		/* OPAL call to patch slw with the new HID0 value */
+		u64 cpu_pir = hard_smp_processor_id();
+
+		opal_slw_set_reg(cpu_pir, SPRN_HID0, hid0);
+	}
+}
+
 static void unsplit_core(void)
 {
 	u64 hid0, mask;
@@ -179,6 +191,7 @@ static void unsplit_core(void)
 	hid0 = mfspr(SPRN_HID0);
 	hid0 &= ~HID0_POWER8_DYNLPARDIS;
 	mtspr(SPRN_HID0, hid0);
+	update_hid_in_slw(hid0);
 
 	while (mfspr(SPRN_HID0) & mask)
 		cpu_relax();
@@ -215,6 +228,7 @@ static void split_core(int new_mode)
 	hid0  = mfspr(SPRN_HID0);
 	hid0 |= HID0_POWER8_DYNLPARDIS | split_parms[i].value;
 	mtspr(SPRN_HID0, hid0);
+	update_hid_in_slw(hid0);
 
 	/* Wait for it to happen */
 	while (!(mfspr(SPRN_HID0) & split_parms[i].mask))
@@ -251,6 +265,25 @@ bool cpu_core_split_required(void)
 	return true;
 }
 
+void update_subcore_sibling_mask(void)
+{
+	int cpu;
+	/*
+	 * sibling mask for the first cpu. Left shift this by required bits
+	 * to get sibling mask for the rest of the cpus.
+	 */
+	int sibling_mask_first_cpu =  (1 << threads_per_subcore) - 1;
+
+	for_each_possible_cpu(cpu) {
+		int tid = cpu_thread_in_core(cpu);
+		int offset = (tid / threads_per_subcore) * threads_per_subcore;
+		int mask = sibling_mask_first_cpu << offset;
+
+		paca[cpu].subcore_sibling_mask = mask;
+
+	}
+}
+
 static int cpu_update_split_mode(void *data)
 {
 	int cpu, new_mode = *(int *)data;
@@ -284,6 +317,7 @@ static int cpu_update_split_mode(void *data)
 		/* Make the new mode public */
 		subcores_per_core = new_mode;
 		threads_per_subcore = threads_per_core / subcores_per_core;
+		update_subcore_sibling_mask();
 
 		/* Make sure the new mode is written before we exit */
 		mb();
diff --git a/arch/powerpc/platforms/powernv/subcore.h b/arch/powerpc/platforms/powernv/subcore.h
index 148abc91debf..84e02ae52895 100644
--- a/arch/powerpc/platforms/powernv/subcore.h
+++ b/arch/powerpc/platforms/powernv/subcore.h
@@ -14,5 +14,12 @@
 #define SYNC_STEP_FINISHED	3	/* Set by secondary when split/unsplit is done */
 
 #ifndef __ASSEMBLY__
+
+#ifdef CONFIG_SMP
 void split_core_secondary_loop(u8 *state);
-#endif
+extern void update_subcore_sibling_mask(void);
+#else
+static inline void update_subcore_sibling_mask(void) { };
+#endif /* CONFIG_SMP */
+
+#endif /* __ASSEMBLY__ */