1/*
2 *  This file contains idle entry/exit functions for POWER7,
3 *  POWER8 and POWER9 CPUs.
4 *
5 *  This program is free software; you can redistribute it and/or
6 *  modify it under the terms of the GNU General Public License
7 *  as published by the Free Software Foundation; either version
8 *  2 of the License, or (at your option) any later version.
9 */
10
11#include <linux/threads.h>
12#include <asm/processor.h>
13#include <asm/page.h>
14#include <asm/cputable.h>
15#include <asm/thread_info.h>
16#include <asm/ppc_asm.h>
17#include <asm/asm-offsets.h>
18#include <asm/ppc-opcode.h>
19#include <asm/hw_irq.h>
20#include <asm/kvm_book3s_asm.h>
21#include <asm/opal.h>
22#include <asm/cpuidle.h>
23#include <asm/book3s/64/mmu-hash.h>
24#include <asm/mmu.h>
25
26#undef DEBUG
27
28/*
29 * Use unused space in the interrupt stack to save and restore
30 * registers for winkle support.
31 */
32#define _SDR1	GPR3
33#define _RPR	GPR4
34#define _SPURR	GPR5
35#define _PURR	GPR6
36#define _TSCR	GPR7
37#define _DSCR	GPR8
38#define _AMOR	GPR9
39#define _WORT	GPR10
40#define _WORC	GPR11
41#define _PTCR	GPR12
42
43#define PSSCR_EC_ESL_MASK_SHIFTED          (PSSCR_EC | PSSCR_ESL) >> 16
44
45	.text
46
47/*
48 * Used by threads before entering deep idle states. Saves SPRs
49 * in interrupt stack frame
50 */
51save_sprs_to_stack:
52	/*
53	 * Note all register i.e per-core, per-subcore or per-thread is saved
54	 * here since any thread in the core might wake up first
55	 */
56BEGIN_FTR_SECTION
57	mfspr	r3,SPRN_PTCR
58	std	r3,_PTCR(r1)
59	/*
60	 * Note - SDR1 is dropped in Power ISA v3. Hence not restoring
61	 * SDR1 here
62	 */
63FTR_SECTION_ELSE
64	mfspr	r3,SPRN_SDR1
65	std	r3,_SDR1(r1)
66ALT_FTR_SECTION_END_IFSET(CPU_FTR_ARCH_300)
67	mfspr	r3,SPRN_RPR
68	std	r3,_RPR(r1)
69	mfspr	r3,SPRN_SPURR
70	std	r3,_SPURR(r1)
71	mfspr	r3,SPRN_PURR
72	std	r3,_PURR(r1)
73	mfspr	r3,SPRN_TSCR
74	std	r3,_TSCR(r1)
75	mfspr	r3,SPRN_DSCR
76	std	r3,_DSCR(r1)
77	mfspr	r3,SPRN_AMOR
78	std	r3,_AMOR(r1)
79	mfspr	r3,SPRN_WORT
80	std	r3,_WORT(r1)
81	mfspr	r3,SPRN_WORC
82	std	r3,_WORC(r1)
83
84	blr
85
86/*
87 * Used by threads when the lock bit of core_idle_state is set.
88 * Threads will spin in HMT_LOW until the lock bit is cleared.
89 * r14 - pointer to core_idle_state
90 * r15 - used to load contents of core_idle_state
91 * r9  - used as a temporary variable
92 */
93
94core_idle_lock_held:
95	HMT_LOW
963:	lwz	r15,0(r14)
97	andi.   r15,r15,PNV_CORE_IDLE_LOCK_BIT
98	bne	3b
99	HMT_MEDIUM
100	lwarx	r15,0,r14
101	andi.	r9,r15,PNV_CORE_IDLE_LOCK_BIT
102	bne	core_idle_lock_held
103	blr
104
105/*
106 * Pass requested state in r3:
107 *	r3 - PNV_THREAD_NAP/SLEEP/WINKLE in POWER8
108 *	   - Requested STOP state in POWER9
109 *
110 * To check IRQ_HAPPENED in r4
111 * 	0 - don't check
112 * 	1 - check
113 *
114 * Address to 'rfid' to in r5
115 */
116_GLOBAL(pnv_powersave_common)
117	/* Use r3 to pass state nap/sleep/winkle */
118	/* NAP is a state loss, we create a regs frame on the
119	 * stack, fill it up with the state we care about and
120	 * stick a pointer to it in PACAR1. We really only
121	 * need to save PC, some CR bits and the NV GPRs,
122	 * but for now an interrupt frame will do.
123	 */
124	mflr	r0
125	std	r0,16(r1)
126	stdu	r1,-INT_FRAME_SIZE(r1)
127	std	r0,_LINK(r1)
128	std	r0,_NIP(r1)
129
130	/* Hard disable interrupts */
131	mfmsr	r9
132	rldicl	r9,r9,48,1
133	rotldi	r9,r9,16
134	mtmsrd	r9,1			/* hard-disable interrupts */
135
136	/* Check if something happened while soft-disabled */
137	lbz	r0,PACAIRQHAPPENED(r13)
138	andi.	r0,r0,~PACA_IRQ_HARD_DIS@l
139	beq	1f
140	cmpwi	cr0,r4,0
141	beq	1f
142	addi	r1,r1,INT_FRAME_SIZE
143	ld	r0,16(r1)
144	li	r3,0			/* Return 0 (no nap) */
145	mtlr	r0
146	blr
147
1481:	/* We mark irqs hard disabled as this is the state we'll
149	 * be in when returning and we need to tell arch_local_irq_restore()
150	 * about it
151	 */
152	li	r0,PACA_IRQ_HARD_DIS
153	stb	r0,PACAIRQHAPPENED(r13)
154
155	/* We haven't lost state ... yet */
156	li	r0,0
157	stb	r0,PACA_NAPSTATELOST(r13)
158
159	/* Continue saving state */
160	SAVE_GPR(2, r1)
161	SAVE_NVGPRS(r1)
162	mfcr	r4
163	std	r4,_CCR(r1)
164	std	r9,_MSR(r1)
165	std	r1,PACAR1(r13)
166
167	/*
168	 * Go to real mode to do the nap, as required by the architecture.
169	 * Also, we need to be in real mode before setting hwthread_state,
170	 * because as soon as we do that, another thread can switch
171	 * the MMU context to the guest.
172	 */
173	LOAD_REG_IMMEDIATE(r7, MSR_IDLE)
174	li	r6, MSR_RI
175	andc	r6, r9, r6
176	mtmsrd	r6, 1		/* clear RI before setting SRR0/1 */
177	mtspr	SPRN_SRR0, r5
178	mtspr	SPRN_SRR1, r7
179	rfid
180
181	.globl pnv_enter_arch207_idle_mode
182pnv_enter_arch207_idle_mode:
183#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
184	/* Tell KVM we're entering idle */
185	li	r4,KVM_HWTHREAD_IN_IDLE
186	/******************************************************/
187	/*  N O T E   W E L L    ! ! !    N O T E   W E L L   */
188	/* The following store to HSTATE_HWTHREAD_STATE(r13)  */
189	/* MUST occur in real mode, i.e. with the MMU off,    */
190	/* and the MMU must stay off until we clear this flag */
191	/* and test HSTATE_HWTHREAD_REQ(r13) in the system    */
192	/* reset interrupt vector in exceptions-64s.S.        */
193	/* The reason is that another thread can switch the   */
194	/* MMU to a guest context whenever this flag is set   */
195	/* to KVM_HWTHREAD_IN_IDLE, and if the MMU was on,    */
196	/* that would potentially cause this thread to start  */
197	/* executing instructions from guest memory in        */
198	/* hypervisor mode, leading to a host crash or data   */
199	/* corruption, or worse.                              */
200	/******************************************************/
201	stb	r4,HSTATE_HWTHREAD_STATE(r13)
202#endif
203	stb	r3,PACA_THREAD_IDLE_STATE(r13)
204	cmpwi	cr3,r3,PNV_THREAD_SLEEP
205	bge	cr3,2f
206	IDLE_STATE_ENTER_SEQ_NORET(PPC_NAP)
207	/* No return */
2082:
209	/* Sleep or winkle */
210	lbz	r7,PACA_THREAD_MASK(r13)
211	ld	r14,PACA_CORE_IDLE_STATE_PTR(r13)
212lwarx_loop1:
213	lwarx	r15,0,r14
214
215	andi.   r9,r15,PNV_CORE_IDLE_LOCK_BIT
216	bnel	core_idle_lock_held
217
218	andc	r15,r15,r7			/* Clear thread bit */
219
220	andi.	r15,r15,PNV_CORE_IDLE_THREAD_BITS
221
222/*
223 * If cr0 = 0, then current thread is the last thread of the core entering
224 * sleep. Last thread needs to execute the hardware bug workaround code if
225 * required by the platform.
226 * Make the workaround call unconditionally here. The below branch call is
227 * patched out when the idle states are discovered if the platform does not
228 * require it.
229 */
230.global pnv_fastsleep_workaround_at_entry
231pnv_fastsleep_workaround_at_entry:
232	beq	fastsleep_workaround_at_entry
233
234	stwcx.	r15,0,r14
235	bne-	lwarx_loop1
236	isync
237
238common_enter: /* common code for all the threads entering sleep or winkle */
239	bgt	cr3,enter_winkle
240	IDLE_STATE_ENTER_SEQ_NORET(PPC_SLEEP)
241
242fastsleep_workaround_at_entry:
243	ori	r15,r15,PNV_CORE_IDLE_LOCK_BIT
244	stwcx.	r15,0,r14
245	bne-	lwarx_loop1
246	isync
247
248	/* Fast sleep workaround */
249	li	r3,1
250	li	r4,1
251	bl	opal_config_cpu_idle_state
252
253	/* Clear Lock bit */
254	li	r0,0
255	lwsync
256	stw	r0,0(r14)
257	b	common_enter
258
259enter_winkle:
260	bl	save_sprs_to_stack
261
262	IDLE_STATE_ENTER_SEQ_NORET(PPC_WINKLE)
263
264/*
265 * r3 - PSSCR value corresponding to the requested stop state.
266 */
267power_enter_stop:
268#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
269	/* Tell KVM we're entering idle */
270	li	r4,KVM_HWTHREAD_IN_IDLE
271	/* DO THIS IN REAL MODE!  See comment above. */
272	stb	r4,HSTATE_HWTHREAD_STATE(r13)
273#endif
274/*
275 * Check if we are executing the lite variant with ESL=EC=0
276 */
277	andis.   r4,r3,PSSCR_EC_ESL_MASK_SHIFTED
278	clrldi   r3,r3,60 /* r3 = Bits[60:63] = Requested Level (RL) */
279	bne	 1f
280	IDLE_STATE_ENTER_SEQ(PPC_STOP)
281	li	r3,0  /* Since we didn't lose state, return 0 */
282	b 	pnv_wakeup_noloss
283/*
284 * Check if the requested state is a deep idle state.
285 */
2861:	LOAD_REG_ADDRBASE(r5,pnv_first_deep_stop_state)
287	ld	r4,ADDROFF(pnv_first_deep_stop_state)(r5)
288	cmpd	r3,r4
289	bge	2f
290	IDLE_STATE_ENTER_SEQ_NORET(PPC_STOP)
2912:
292/*
293 * Entering deep idle state.
294 * Clear thread bit in PACA_CORE_IDLE_STATE, save SPRs to
295 * stack and enter stop
296 */
297	lbz     r7,PACA_THREAD_MASK(r13)
298	ld      r14,PACA_CORE_IDLE_STATE_PTR(r13)
299
300lwarx_loop_stop:
301	lwarx   r15,0,r14
302	andi.   r9,r15,PNV_CORE_IDLE_LOCK_BIT
303	bnel    core_idle_lock_held
304	andc    r15,r15,r7                      /* Clear thread bit */
305
306	stwcx.  r15,0,r14
307	bne-    lwarx_loop_stop
308	isync
309
310	bl	save_sprs_to_stack
311
312	IDLE_STATE_ENTER_SEQ_NORET(PPC_STOP)
313
314_GLOBAL(power7_idle)
315	/* Now check if user or arch enabled NAP mode */
316	LOAD_REG_ADDRBASE(r3,powersave_nap)
317	lwz	r4,ADDROFF(powersave_nap)(r3)
318	cmpwi	0,r4,0
319	beqlr
320	li	r3, 1
321	/* fall through */
322
323_GLOBAL(power7_nap)
324	mr	r4,r3
325	li	r3,PNV_THREAD_NAP
326	LOAD_REG_ADDR(r5, pnv_enter_arch207_idle_mode)
327	b	pnv_powersave_common
328	/* No return */
329
330_GLOBAL(power7_sleep)
331	li	r3,PNV_THREAD_SLEEP
332	li	r4,1
333	LOAD_REG_ADDR(r5, pnv_enter_arch207_idle_mode)
334	b	pnv_powersave_common
335	/* No return */
336
337_GLOBAL(power7_winkle)
338	li	r3,PNV_THREAD_WINKLE
339	li	r4,1
340	LOAD_REG_ADDR(r5, pnv_enter_arch207_idle_mode)
341	b	pnv_powersave_common
342	/* No return */
343
344#define CHECK_HMI_INTERRUPT						\
345	mfspr	r0,SPRN_SRR1;						\
346BEGIN_FTR_SECTION_NESTED(66);						\
347	rlwinm	r0,r0,45-31,0xf;  /* extract wake reason field (P8) */	\
348FTR_SECTION_ELSE_NESTED(66);						\
349	rlwinm	r0,r0,45-31,0xe;  /* P7 wake reason field is 3 bits */	\
350ALT_FTR_SECTION_END_NESTED_IFSET(CPU_FTR_ARCH_207S, 66);		\
351	cmpwi	r0,0xa;			/* Hypervisor maintenance ? */	\
352	bne	20f;							\
353	/* Invoke opal call to handle hmi */				\
354	ld	r2,PACATOC(r13);					\
355	ld	r1,PACAR1(r13);						\
356	std	r3,ORIG_GPR3(r1);	/* Save original r3 */		\
357	li	r3,0;			/* NULL argument */		\
358	bl	hmi_exception_realmode;					\
359	nop;								\
360	ld	r3,ORIG_GPR3(r1);	/* Restore original r3 */	\
36120:	nop;
362
363/*
364 * r3 - The PSSCR value corresponding to the stop state.
365 * r4 - The PSSCR mask corrresonding to the stop state.
366 */
367_GLOBAL(power9_idle_stop)
368	mfspr   r5,SPRN_PSSCR
369	andc    r5,r5,r4
370	or      r3,r3,r5
371	mtspr 	SPRN_PSSCR,r3
372	LOAD_REG_ADDR(r5,power_enter_stop)
373	li	r4,1
374	b	pnv_powersave_common
375	/* No return */
376/*
377 * Called from reset vector. Check whether we have woken up with
378 * hypervisor state loss. If yes, restore hypervisor state and return
379 * back to reset vector.
380 *
381 * r13 - Contents of HSPRG0
382 * cr3 - set to gt if waking up with partial/complete hypervisor state loss
383 */
384_GLOBAL(pnv_restore_hyp_resource)
385BEGIN_FTR_SECTION
386	ld	r2,PACATOC(r13);
387	/*
388	 * POWER ISA 3. Use PSSCR to determine if we
389	 * are waking up from deep idle state
390	 */
391	LOAD_REG_ADDRBASE(r5,pnv_first_deep_stop_state)
392	ld	r4,ADDROFF(pnv_first_deep_stop_state)(r5)
393
394	mfspr	r5,SPRN_PSSCR
395	/*
396	 * 0-3 bits correspond to Power-Saving Level Status
397	 * which indicates the idle state we are waking up from
398	 */
399	rldicl  r5,r5,4,60
400	cmpd	cr4,r5,r4
401	bge	cr4,pnv_wakeup_tb_loss
402	/*
403	 * Waking up without hypervisor state loss. Return to
404	 * reset vector
405	 */
406	blr
407
408END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
409
410	/*
411	 * POWER ISA 2.07 or less.
412	 * Check if last bit of HSPGR0 is set. This indicates whether we are
413	 * waking up from winkle.
414	 */
415	clrldi	r5,r13,63
416	clrrdi	r13,r13,1
417
418	/* Now that we are sure r13 is corrected, load TOC */
419	ld	r2,PACATOC(r13);
420	cmpwi	cr4,r5,1
421	mtspr	SPRN_HSPRG0,r13
422
423	lbz	r0,PACA_THREAD_IDLE_STATE(r13)
424	cmpwi   cr2,r0,PNV_THREAD_NAP
425	bgt     cr2,pnv_wakeup_tb_loss	/* Either sleep or Winkle */
426
427	/*
428	 * We fall through here if PACA_THREAD_IDLE_STATE shows we are waking
429	 * up from nap. At this stage CR3 shouldn't contains 'gt' since that
430	 * indicates we are waking with hypervisor state loss from nap.
431	 */
432	bgt	cr3,.
433
434	blr	/* Return back to System Reset vector from where
435		   pnv_restore_hyp_resource was invoked */
436
437/*
438 * Called if waking up from idle state which can cause either partial or
439 * complete hyp state loss.
440 * In POWER8, called if waking up from fastsleep or winkle
441 * In POWER9, called if waking up from stop state >= pnv_first_deep_stop_state
442 *
443 * r13 - PACA
444 * cr3 - gt if waking up with partial/complete hypervisor state loss
445 * cr4 - gt or eq if waking up from complete hypervisor state loss.
446 */
447_GLOBAL(pnv_wakeup_tb_loss)
448	ld	r1,PACAR1(r13)
449	/*
450	 * Before entering any idle state, the NVGPRs are saved in the stack
451	 * and they are restored before switching to the process context. Hence
452	 * until they are restored, they are free to be used.
453	 *
454	 * Save SRR1 and LR in NVGPRs as they might be clobbered in
455	 * opal_call() (called in CHECK_HMI_INTERRUPT). SRR1 is required
456	 * to determine the wakeup reason if we branch to kvm_start_guest. LR
457	 * is required to return back to reset vector after hypervisor state
458	 * restore is complete.
459	 */
460	mflr	r17
461	mfspr	r16,SPRN_SRR1
462BEGIN_FTR_SECTION
463	CHECK_HMI_INTERRUPT
464END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
465
466	lbz	r7,PACA_THREAD_MASK(r13)
467	ld	r14,PACA_CORE_IDLE_STATE_PTR(r13)
468lwarx_loop2:
469	lwarx	r15,0,r14
470	andi.	r9,r15,PNV_CORE_IDLE_LOCK_BIT
471	/*
472	 * Lock bit is set in one of the 2 cases-
473	 * a. In the sleep/winkle enter path, the last thread is executing
474	 * fastsleep workaround code.
475	 * b. In the wake up path, another thread is executing fastsleep
476	 * workaround undo code or resyncing timebase or restoring context
477	 * In either case loop until the lock bit is cleared.
478	 */
479	bnel	core_idle_lock_held
480
481	cmpwi	cr2,r15,0
482
483	/*
484	 * At this stage
485	 * cr2 - eq if first thread to wakeup in core
486	 * cr3-  gt if waking up with partial/complete hypervisor state loss
487	 * cr4 - gt or eq if waking up from complete hypervisor state loss.
488	 */
489
490	ori	r15,r15,PNV_CORE_IDLE_LOCK_BIT
491	stwcx.	r15,0,r14
492	bne-	lwarx_loop2
493	isync
494
495BEGIN_FTR_SECTION
496	lbz	r4,PACA_SUBCORE_SIBLING_MASK(r13)
497	and	r4,r4,r15
498	cmpwi	r4,0	/* Check if first in subcore */
499
500	or	r15,r15,r7		/* Set thread bit */
501	beq	first_thread_in_subcore
502END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
503
504	or	r15,r15,r7		/* Set thread bit */
505	beq	cr2,first_thread_in_core
506
507	/* Not first thread in core or subcore to wake up */
508	b	clear_lock
509
510first_thread_in_subcore:
511	/*
512	 * If waking up from sleep, subcore state is not lost. Hence
513	 * skip subcore state restore
514	 */
515	blt	cr4,subcore_state_restored
516
517	/* Restore per-subcore state */
518	ld      r4,_SDR1(r1)
519	mtspr   SPRN_SDR1,r4
520
521	ld      r4,_RPR(r1)
522	mtspr   SPRN_RPR,r4
523	ld	r4,_AMOR(r1)
524	mtspr	SPRN_AMOR,r4
525
526subcore_state_restored:
527	/*
528	 * Check if the thread is also the first thread in the core. If not,
529	 * skip to clear_lock.
530	 */
531	bne	cr2,clear_lock
532
533first_thread_in_core:
534
535	/*
536	 * First thread in the core waking up from any state which can cause
537	 * partial or complete hypervisor state loss. It needs to
538	 * call the fastsleep workaround code if the platform requires it.
539	 * Call it unconditionally here. The below branch instruction will
540	 * be patched out if the platform does not have fastsleep or does not
541	 * require the workaround. Patching will be performed during the
542	 * discovery of idle-states.
543	 */
544.global pnv_fastsleep_workaround_at_exit
545pnv_fastsleep_workaround_at_exit:
546	b	fastsleep_workaround_at_exit
547
548timebase_resync:
549	/*
550	 * Use cr3 which indicates that we are waking up with atleast partial
551	 * hypervisor state loss to determine if TIMEBASE RESYNC is needed.
552	 */
553	ble	cr3,clear_lock
554	/* Time base re-sync */
555	bl	opal_resync_timebase;
556	/*
557	 * If waking up from sleep, per core state is not lost, skip to
558	 * clear_lock.
559	 */
560	blt	cr4,clear_lock
561
562	/*
563	 * First thread in the core to wake up and its waking up with
564	 * complete hypervisor state loss. Restore per core hypervisor
565	 * state.
566	 */
567BEGIN_FTR_SECTION
568	ld	r4,_PTCR(r1)
569	mtspr	SPRN_PTCR,r4
570	ld	r4,_RPR(r1)
571	mtspr	SPRN_RPR,r4
572END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
573
574	ld	r4,_TSCR(r1)
575	mtspr	SPRN_TSCR,r4
576	ld	r4,_WORC(r1)
577	mtspr	SPRN_WORC,r4
578
579clear_lock:
580	andi.	r15,r15,PNV_CORE_IDLE_THREAD_BITS
581	lwsync
582	stw	r15,0(r14)
583
584common_exit:
585	/*
586	 * Common to all threads.
587	 *
588	 * If waking up from sleep, hypervisor state is not lost. Hence
589	 * skip hypervisor state restore.
590	 */
591	blt	cr4,hypervisor_state_restored
592
593	/* Waking up from winkle */
594
595BEGIN_MMU_FTR_SECTION
596	b	no_segments
597END_MMU_FTR_SECTION_IFSET(MMU_FTR_TYPE_RADIX)
598	/* Restore SLB  from PACA */
599	ld	r8,PACA_SLBSHADOWPTR(r13)
600
601	.rept	SLB_NUM_BOLTED
602	li	r3, SLBSHADOW_SAVEAREA
603	LDX_BE	r5, r8, r3
604	addi	r3, r3, 8
605	LDX_BE	r6, r8, r3
606	andis.	r7,r5,SLB_ESID_V@h
607	beq	1f
608	slbmte	r6,r5
6091:	addi	r8,r8,16
610	.endr
611no_segments:
612
613	/* Restore per thread state */
614
615	ld	r4,_SPURR(r1)
616	mtspr	SPRN_SPURR,r4
617	ld	r4,_PURR(r1)
618	mtspr	SPRN_PURR,r4
619	ld	r4,_DSCR(r1)
620	mtspr	SPRN_DSCR,r4
621	ld	r4,_WORT(r1)
622	mtspr	SPRN_WORT,r4
623
624	/* Call cur_cpu_spec->cpu_restore() */
625	LOAD_REG_ADDR(r4, cur_cpu_spec)
626	ld	r4,0(r4)
627	ld	r12,CPU_SPEC_RESTORE(r4)
628#ifdef PPC64_ELF_ABI_v1
629	ld	r12,0(r12)
630#endif
631	mtctr	r12
632	bctrl
633
634hypervisor_state_restored:
635
636	mtspr	SPRN_SRR1,r16
637	mtlr	r17
638	blr	/* Return back to System Reset vector from where
639		   pnv_restore_hyp_resource was invoked */
640
641fastsleep_workaround_at_exit:
642	li	r3,1
643	li	r4,0
644	bl	opal_config_cpu_idle_state
645	b	timebase_resync
646
647/*
648 * R3 here contains the value that will be returned to the caller
649 * of power7_nap.
650 */
651_GLOBAL(pnv_wakeup_loss)
652	ld	r1,PACAR1(r13)
653BEGIN_FTR_SECTION
654	CHECK_HMI_INTERRUPT
655END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
656	REST_NVGPRS(r1)
657	REST_GPR(2, r1)
658	ld	r6,_CCR(r1)
659	ld	r4,_MSR(r1)
660	ld	r5,_NIP(r1)
661	addi	r1,r1,INT_FRAME_SIZE
662	mtcr	r6
663	mtspr	SPRN_SRR1,r4
664	mtspr	SPRN_SRR0,r5
665	rfid
666
667/*
668 * R3 here contains the value that will be returned to the caller
669 * of power7_nap.
670 */
671_GLOBAL(pnv_wakeup_noloss)
672	lbz	r0,PACA_NAPSTATELOST(r13)
673	cmpwi	r0,0
674	bne	pnv_wakeup_loss
675BEGIN_FTR_SECTION
676	CHECK_HMI_INTERRUPT
677END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
678	ld	r1,PACAR1(r13)
679	ld	r6,_CCR(r1)
680	ld	r4,_MSR(r1)
681	ld	r5,_NIP(r1)
682	addi	r1,r1,INT_FRAME_SIZE
683	mtcr	r6
684	mtspr	SPRN_SRR1,r4
685	mtspr	SPRN_SRR0,r5
686	rfid
687