1/*
2 * This file contains the 64-bit "server" PowerPC variant
3 * of the low level exception handling including exception
4 * vectors, exception return, part of the slb and stab
5 * handling and other fixed offset specific things.
6 *
7 * This file is meant to be #included from head_64.S due to
8 * position dependent assembly.
9 *
10 * Most of this originates from head_64.S and thus has the same
11 * copyright history.
12 *
13 */
14
15#include <asm/hw_irq.h>
16#include <asm/exception-64s.h>
17#include <asm/ptrace.h>
18#include <asm/cpuidle.h>
19#include <asm/head-64.h>
20
21/*
22 * There are a few constraints to be concerned with.
23 * - Real mode exceptions code/data must be located at their physical location.
24 * - Virtual mode exceptions must be mapped at their 0xc000... location.
25 * - Fixed location code must not call directly beyond the __end_interrupts
26 *   area when built with CONFIG_RELOCATABLE. LOAD_HANDLER / bctr sequence
27 *   must be used.
28 * - LOAD_HANDLER targets must be within first 64K of physical 0 /
29 *   virtual 0xc00...
30 * - Conditional branch targets must be within +/-32K of caller.
31 *
32 * "Virtual exceptions" run with relocation on (MSR_IR=1, MSR_DR=1), and
33 * therefore don't have to run in physically located code or rfid to
34 * virtual mode kernel code. However on relocatable kernels they do have
35 * to branch to KERNELBASE offset because the rest of the kernel (outside
36 * the exception vectors) may be located elsewhere.
37 *
38 * Virtual exceptions correspond with physical, except their entry points
39 * are offset by 0xc000000000000000 and also tend to get an added 0x4000
40 * offset applied. Virtual exceptions are enabled with the Alternate
41 * Interrupt Location (AIL) bit set in the LPCR. However this does not
42 * guarantee they will be delivered virtually. Some conditions (see the ISA)
43 * cause exceptions to be delivered in real mode.
44 *
45 * It's impossible to receive interrupts below 0x300 via AIL.
46 *
47 * KVM: None of the virtual exceptions are from the guest. Anything that
48 * escalated to HV=1 from HV=0 is delivered via real mode handlers.
49 *
50 *
51 * We layout physical memory as follows:
52 * 0x0000 - 0x00ff : Secondary processor spin code
53 * 0x0100 - 0x18ff : Real mode pSeries interrupt vectors
54 * 0x1900 - 0x3fff : Real mode trampolines
55 * 0x4000 - 0x58ff : Relon (IR=1,DR=1) mode pSeries interrupt vectors
56 * 0x5900 - 0x6fff : Relon mode trampolines
57 * 0x7000 - 0x7fff : FWNMI data area
58 * 0x8000 -   .... : Common interrupt handlers, remaining early
59 *                   setup code, rest of kernel.
60 *
61 * We could reclaim 0x4000-0x42ff for real mode trampolines if the space
62 * is necessary. Until then it's more consistent to explicitly put VIRT_NONE
63 * vectors there.
64 */
65OPEN_FIXED_SECTION(real_vectors,        0x0100, 0x1900)
66OPEN_FIXED_SECTION(real_trampolines,    0x1900, 0x4000)
67OPEN_FIXED_SECTION(virt_vectors,        0x4000, 0x5900)
68OPEN_FIXED_SECTION(virt_trampolines,    0x5900, 0x7000)
69#if defined(CONFIG_PPC_PSERIES) || defined(CONFIG_PPC_POWERNV)
70/*
71 * Data area reserved for FWNMI option.
72 * This address (0x7000) is fixed by the RPA.
73 * pseries and powernv need to keep the whole page from
74 * 0x7000 to 0x8000 free for use by the firmware
75 */
76ZERO_FIXED_SECTION(fwnmi_page,          0x7000, 0x8000)
77OPEN_TEXT_SECTION(0x8000)
78#else
79OPEN_TEXT_SECTION(0x7000)
80#endif
81
82USE_FIXED_SECTION(real_vectors)
83
84/*
85 * This is the start of the interrupt handlers for pSeries
86 * This code runs with relocation off.
87 * Code from here to __end_interrupts gets copied down to real
88 * address 0x100 when we are running a relocatable kernel.
89 * Therefore any relative branches in this section must only
90 * branch to labels in this section.
91 */
92	.globl __start_interrupts
93__start_interrupts:
94
95/* No virt vectors corresponding with 0x0..0x100 */
96EXC_VIRT_NONE(0x4000, 0x100)
97
98
99#ifdef CONFIG_PPC_P7_NAP
100	/*
101	 * If running native on arch 2.06 or later, check if we are waking up
102	 * from nap/sleep/winkle, and branch to idle handler. This tests SRR1
103	 * bits 46:47. A non-0 value indicates that we are coming from a power
104	 * saving state. The idle wakeup handler initially runs in real mode,
105	 * but we branch to the 0xc000... address so we can turn on relocation
106	 * with mtmsr.
107	 */
108#define IDLETEST(n)							\
109	BEGIN_FTR_SECTION ;						\
110	mfspr	r10,SPRN_SRR1 ;						\
111	rlwinm.	r10,r10,47-31,30,31 ;					\
112	beq-	1f ;							\
113	cmpwi	cr3,r10,2 ;						\
114	BRANCH_TO_C000(r10, system_reset_idle_common) ;			\
1151:									\
116	END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
117#else
118#define IDLETEST NOTEST
119#endif
120
121EXC_REAL_BEGIN(system_reset, 0x100, 0x100)
122	SET_SCRATCH0(r13)
123	/*
124	 * MSR_RI is not enabled, because PACA_EXNMI and nmi stack is
125	 * being used, so a nested NMI exception would corrupt it.
126	 */
127	EXCEPTION_PROLOG_PSERIES_NORI(PACA_EXNMI, system_reset_common, EXC_STD,
128				 IDLETEST, 0x100)
129
130EXC_REAL_END(system_reset, 0x100, 0x100)
131EXC_VIRT_NONE(0x4100, 0x100)
132
133#ifdef CONFIG_PPC_P7_NAP
134EXC_COMMON_BEGIN(system_reset_idle_common)
135	mfspr	r12,SPRN_SRR1
136	b	pnv_powersave_wakeup
137#endif
138
139EXC_COMMON_BEGIN(system_reset_common)
140	/*
141	 * Increment paca->in_nmi then enable MSR_RI. SLB or MCE will be able
142	 * to recover, but nested NMI will notice in_nmi and not recover
143	 * because of the use of the NMI stack. in_nmi reentrancy is tested in
144	 * system_reset_exception.
145	 */
146	lhz	r10,PACA_IN_NMI(r13)
147	addi	r10,r10,1
148	sth	r10,PACA_IN_NMI(r13)
149	li	r10,MSR_RI
150	mtmsrd 	r10,1
151
152	mr	r10,r1
153	ld	r1,PACA_NMI_EMERG_SP(r13)
154	subi	r1,r1,INT_FRAME_SIZE
155	EXCEPTION_COMMON_NORET_STACK(PACA_EXNMI, 0x100,
156			system_reset, system_reset_exception,
157			ADD_NVGPRS;ADD_RECONCILE)
158
159	/*
160	 * The stack is no longer in use, decrement in_nmi.
161	 */
162	lhz	r10,PACA_IN_NMI(r13)
163	subi	r10,r10,1
164	sth	r10,PACA_IN_NMI(r13)
165
166	b	ret_from_except
167
168#ifdef CONFIG_PPC_PSERIES
169/*
170 * Vectors for the FWNMI option.  Share common code.
171 */
172TRAMP_REAL_BEGIN(system_reset_fwnmi)
173	SET_SCRATCH0(r13)		/* save r13 */
174	/* See comment at system_reset exception */
175	EXCEPTION_PROLOG_PSERIES_NORI(PACA_EXNMI, system_reset_common,
176						EXC_STD, NOTEST, 0x100)
177#endif /* CONFIG_PPC_PSERIES */
178
179
180EXC_REAL_BEGIN(machine_check, 0x200, 0x100)
181	/* This is moved out of line as it can be patched by FW, but
182	 * some code path might still want to branch into the original
183	 * vector
184	 */
185	SET_SCRATCH0(r13)		/* save r13 */
186	EXCEPTION_PROLOG_0(PACA_EXMC)
187BEGIN_FTR_SECTION
188	b	machine_check_powernv_early
189FTR_SECTION_ELSE
190	b	machine_check_pSeries_0
191ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
192EXC_REAL_END(machine_check, 0x200, 0x100)
193EXC_VIRT_NONE(0x4200, 0x100)
194TRAMP_REAL_BEGIN(machine_check_powernv_early)
195BEGIN_FTR_SECTION
196	EXCEPTION_PROLOG_1(PACA_EXMC, NOTEST, 0x200)
197	/*
198	 * Register contents:
199	 * R13		= PACA
200	 * R9		= CR
201	 * Original R9 to R13 is saved on PACA_EXMC
202	 *
203	 * Switch to mc_emergency stack and handle re-entrancy (we limit
204	 * the nested MCE upto level 4 to avoid stack overflow).
205	 * Save MCE registers srr1, srr0, dar and dsisr and then set ME=1
206	 *
207	 * We use paca->in_mce to check whether this is the first entry or
208	 * nested machine check. We increment paca->in_mce to track nested
209	 * machine checks.
210	 *
211	 * If this is the first entry then set stack pointer to
212	 * paca->mc_emergency_sp, otherwise r1 is already pointing to
213	 * stack frame on mc_emergency stack.
214	 *
215	 * NOTE: We are here with MSR_ME=0 (off), which means we risk a
216	 * checkstop if we get another machine check exception before we do
217	 * rfid with MSR_ME=1.
218	 *
219	 * This interrupt can wake directly from idle. If that is the case,
220	 * the machine check is handled then the idle wakeup code is called
221	 * to restore state. In that case, the POWER9 DD1 idle PACA workaround
222	 * is not applied in the early machine check code, which will cause
223	 * bugs.
224	 */
225	mr	r11,r1			/* Save r1 */
226	lhz	r10,PACA_IN_MCE(r13)
227	cmpwi	r10,0			/* Are we in nested machine check */
228	bne	0f			/* Yes, we are. */
229	/* First machine check entry */
230	ld	r1,PACAMCEMERGSP(r13)	/* Use MC emergency stack */
2310:	subi	r1,r1,INT_FRAME_SIZE	/* alloc stack frame */
232	addi	r10,r10,1		/* increment paca->in_mce */
233	sth	r10,PACA_IN_MCE(r13)
234	/* Limit nested MCE to level 4 to avoid stack overflow */
235	cmpwi	r10,4
236	bgt	2f			/* Check if we hit limit of 4 */
237	std	r11,GPR1(r1)		/* Save r1 on the stack. */
238	std	r11,0(r1)		/* make stack chain pointer */
239	mfspr	r11,SPRN_SRR0		/* Save SRR0 */
240	std	r11,_NIP(r1)
241	mfspr	r11,SPRN_SRR1		/* Save SRR1 */
242	std	r11,_MSR(r1)
243	mfspr	r11,SPRN_DAR		/* Save DAR */
244	std	r11,_DAR(r1)
245	mfspr	r11,SPRN_DSISR		/* Save DSISR */
246	std	r11,_DSISR(r1)
247	std	r9,_CCR(r1)		/* Save CR in stackframe */
248	/* Save r9 through r13 from EXMC save area to stack frame. */
249	EXCEPTION_PROLOG_COMMON_2(PACA_EXMC)
250	mfmsr	r11			/* get MSR value */
251	ori	r11,r11,MSR_ME		/* turn on ME bit */
252	ori	r11,r11,MSR_RI		/* turn on RI bit */
253	LOAD_HANDLER(r12, machine_check_handle_early)
2541:	mtspr	SPRN_SRR0,r12
255	mtspr	SPRN_SRR1,r11
256	rfid
257	b	.	/* prevent speculative execution */
2582:
259	/* Stack overflow. Stay on emergency stack and panic.
260	 * Keep the ME bit off while panic-ing, so that if we hit
261	 * another machine check we checkstop.
262	 */
263	addi	r1,r1,INT_FRAME_SIZE	/* go back to previous stack frame */
264	ld	r11,PACAKMSR(r13)
265	LOAD_HANDLER(r12, unrecover_mce)
266	li	r10,MSR_ME
267	andc	r11,r11,r10		/* Turn off MSR_ME */
268	b	1b
269	b	.	/* prevent speculative execution */
270END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
271
272TRAMP_REAL_BEGIN(machine_check_pSeries)
273	.globl machine_check_fwnmi
274machine_check_fwnmi:
275	SET_SCRATCH0(r13)		/* save r13 */
276	EXCEPTION_PROLOG_0(PACA_EXMC)
277machine_check_pSeries_0:
278	EXCEPTION_PROLOG_1(PACA_EXMC, KVMTEST_PR, 0x200)
279	/*
280	 * MSR_RI is not enabled, because PACA_EXMC is being used, so a
281	 * nested machine check corrupts it. machine_check_common enables
282	 * MSR_RI.
283	 */
284	EXCEPTION_PROLOG_PSERIES_1_NORI(machine_check_common, EXC_STD)
285
286TRAMP_KVM_SKIP(PACA_EXMC, 0x200)
287
288EXC_COMMON_BEGIN(machine_check_common)
289	/*
290	 * Machine check is different because we use a different
291	 * save area: PACA_EXMC instead of PACA_EXGEN.
292	 */
293	mfspr	r10,SPRN_DAR
294	std	r10,PACA_EXMC+EX_DAR(r13)
295	mfspr	r10,SPRN_DSISR
296	stw	r10,PACA_EXMC+EX_DSISR(r13)
297	EXCEPTION_PROLOG_COMMON(0x200, PACA_EXMC)
298	FINISH_NAP
299	RECONCILE_IRQ_STATE(r10, r11)
300	ld	r3,PACA_EXMC+EX_DAR(r13)
301	lwz	r4,PACA_EXMC+EX_DSISR(r13)
302	/* Enable MSR_RI when finished with PACA_EXMC */
303	li	r10,MSR_RI
304	mtmsrd 	r10,1
305	std	r3,_DAR(r1)
306	std	r4,_DSISR(r1)
307	bl	save_nvgprs
308	addi	r3,r1,STACK_FRAME_OVERHEAD
309	bl	machine_check_exception
310	b	ret_from_except
311
312#define MACHINE_CHECK_HANDLER_WINDUP			\
313	/* Clear MSR_RI before setting SRR0 and SRR1. */\
314	li	r0,MSR_RI;				\
315	mfmsr	r9;		/* get MSR value */	\
316	andc	r9,r9,r0;				\
317	mtmsrd	r9,1;		/* Clear MSR_RI */	\
318	/* Move original SRR0 and SRR1 into the respective regs */	\
319	ld	r9,_MSR(r1);				\
320	mtspr	SPRN_SRR1,r9;				\
321	ld	r3,_NIP(r1);				\
322	mtspr	SPRN_SRR0,r3;				\
323	ld	r9,_CTR(r1);				\
324	mtctr	r9;					\
325	ld	r9,_XER(r1);				\
326	mtxer	r9;					\
327	ld	r9,_LINK(r1);				\
328	mtlr	r9;					\
329	REST_GPR(0, r1);				\
330	REST_8GPRS(2, r1);				\
331	REST_GPR(10, r1);				\
332	ld	r11,_CCR(r1);				\
333	mtcr	r11;					\
334	/* Decrement paca->in_mce. */			\
335	lhz	r12,PACA_IN_MCE(r13);			\
336	subi	r12,r12,1;				\
337	sth	r12,PACA_IN_MCE(r13);			\
338	REST_GPR(11, r1);				\
339	REST_2GPRS(12, r1);				\
340	/* restore original r1. */			\
341	ld	r1,GPR1(r1)
342
343#ifdef CONFIG_PPC_P7_NAP
344/*
345 * This is an idle wakeup. Low level machine check has already been
346 * done. Queue the event then call the idle code to do the wake up.
347 */
348EXC_COMMON_BEGIN(machine_check_idle_common)
349	bl	machine_check_queue_event
350
351	/*
352	 * We have not used any non-volatile GPRs here, and as a rule
353	 * most exception code including machine check does not.
354	 * Therefore PACA_NAPSTATELOST does not need to be set. Idle
355	 * wakeup will restore volatile registers.
356	 *
357	 * Load the original SRR1 into r3 for pnv_powersave_wakeup_mce.
358	 *
359	 * Then decrement MCE nesting after finishing with the stack.
360	 */
361	ld	r3,_MSR(r1)
362
363	lhz	r11,PACA_IN_MCE(r13)
364	subi	r11,r11,1
365	sth	r11,PACA_IN_MCE(r13)
366
367	/* Turn off the RI bit because SRR1 is used by idle wakeup code. */
368	/* Recoverability could be improved by reducing the use of SRR1. */
369	li	r11,0
370	mtmsrd	r11,1
371
372	b	pnv_powersave_wakeup_mce
373#endif
374	/*
375	 * Handle machine check early in real mode. We come here with
376	 * ME=1, MMU (IR=0 and DR=0) off and using MC emergency stack.
377	 */
378EXC_COMMON_BEGIN(machine_check_handle_early)
379	std	r0,GPR0(r1)	/* Save r0 */
380	EXCEPTION_PROLOG_COMMON_3(0x200)
381	bl	save_nvgprs
382	addi	r3,r1,STACK_FRAME_OVERHEAD
383	bl	machine_check_early
384	std	r3,RESULT(r1)	/* Save result */
385	ld	r12,_MSR(r1)
386
387#ifdef	CONFIG_PPC_P7_NAP
388	/*
389	 * Check if thread was in power saving mode. We come here when any
390	 * of the following is true:
391	 * a. thread wasn't in power saving mode
392	 * b. thread was in power saving mode with no state loss,
393	 *    supervisor state loss or hypervisor state loss.
394	 *
395	 * Go back to nap/sleep/winkle mode again if (b) is true.
396	 */
397	BEGIN_FTR_SECTION
398	rlwinm.	r11,r12,47-31,30,31
399	bne	machine_check_idle_common
400	END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
401#endif
402
403	/*
404	 * Check if we are coming from hypervisor userspace. If yes then we
405	 * continue in host kernel in V mode to deliver the MC event.
406	 */
407	rldicl.	r11,r12,4,63		/* See if MC hit while in HV mode. */
408	beq	5f
409	andi.	r11,r12,MSR_PR		/* See if coming from user. */
410	bne	9f			/* continue in V mode if we are. */
411
4125:
413#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
414	/*
415	 * We are coming from kernel context. Check if we are coming from
416	 * guest. if yes, then we can continue. We will fall through
417	 * do_kvm_200->kvmppc_interrupt to deliver the MC event to guest.
418	 */
419	lbz	r11,HSTATE_IN_GUEST(r13)
420	cmpwi	r11,0			/* Check if coming from guest */
421	bne	9f			/* continue if we are. */
422#endif
423	/*
424	 * At this point we are not sure about what context we come from.
425	 * Queue up the MCE event and return from the interrupt.
426	 * But before that, check if this is an un-recoverable exception.
427	 * If yes, then stay on emergency stack and panic.
428	 */
429	andi.	r11,r12,MSR_RI
430	bne	2f
4311:	mfspr	r11,SPRN_SRR0
432	LOAD_HANDLER(r10,unrecover_mce)
433	mtspr	SPRN_SRR0,r10
434	ld	r10,PACAKMSR(r13)
435	/*
436	 * We are going down. But there are chances that we might get hit by
437	 * another MCE during panic path and we may run into unstable state
438	 * with no way out. Hence, turn ME bit off while going down, so that
439	 * when another MCE is hit during panic path, system will checkstop
440	 * and hypervisor will get restarted cleanly by SP.
441	 */
442	li	r3,MSR_ME
443	andc	r10,r10,r3		/* Turn off MSR_ME */
444	mtspr	SPRN_SRR1,r10
445	rfid
446	b	.
4472:
448	/*
449	 * Check if we have successfully handled/recovered from error, if not
450	 * then stay on emergency stack and panic.
451	 */
452	ld	r3,RESULT(r1)	/* Load result */
453	cmpdi	r3,0		/* see if we handled MCE successfully */
454
455	beq	1b		/* if !handled then panic */
456	/*
457	 * Return from MC interrupt.
458	 * Queue up the MCE event so that we can log it later, while
459	 * returning from kernel or opal call.
460	 */
461	bl	machine_check_queue_event
462	MACHINE_CHECK_HANDLER_WINDUP
463	rfid
4649:
465	/* Deliver the machine check to host kernel in V mode. */
466	MACHINE_CHECK_HANDLER_WINDUP
467	b	machine_check_pSeries
468
469EXC_COMMON_BEGIN(unrecover_mce)
470	/* Invoke machine_check_exception to print MCE event and panic. */
471	addi	r3,r1,STACK_FRAME_OVERHEAD
472	bl	machine_check_exception
473	/*
474	 * We will not reach here. Even if we did, there is no way out. Call
475	 * unrecoverable_exception and die.
476	 */
4771:	addi	r3,r1,STACK_FRAME_OVERHEAD
478	bl	unrecoverable_exception
479	b	1b
480
481
482EXC_REAL(data_access, 0x300, 0x80)
483EXC_VIRT(data_access, 0x4300, 0x80, 0x300)
484TRAMP_KVM_SKIP(PACA_EXGEN, 0x300)
485
486EXC_COMMON_BEGIN(data_access_common)
487	/*
488	 * Here r13 points to the paca, r9 contains the saved CR,
489	 * SRR0 and SRR1 are saved in r11 and r12,
490	 * r9 - r13 are saved in paca->exgen.
491	 */
492	mfspr	r10,SPRN_DAR
493	std	r10,PACA_EXGEN+EX_DAR(r13)
494	mfspr	r10,SPRN_DSISR
495	stw	r10,PACA_EXGEN+EX_DSISR(r13)
496	EXCEPTION_PROLOG_COMMON(0x300, PACA_EXGEN)
497	RECONCILE_IRQ_STATE(r10, r11)
498	ld	r12,_MSR(r1)
499	ld	r3,PACA_EXGEN+EX_DAR(r13)
500	lwz	r4,PACA_EXGEN+EX_DSISR(r13)
501	li	r5,0x300
502	std	r3,_DAR(r1)
503	std	r4,_DSISR(r1)
504BEGIN_MMU_FTR_SECTION
505	b	do_hash_page		/* Try to handle as hpte fault */
506MMU_FTR_SECTION_ELSE
507	b	handle_page_fault
508ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)
509
510
511EXC_REAL_BEGIN(data_access_slb, 0x380, 0x80)
512	SET_SCRATCH0(r13)
513	EXCEPTION_PROLOG_0(PACA_EXSLB)
514	EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST_PR, 0x380)
515	mr	r12,r3	/* save r3 */
516	mfspr	r3,SPRN_DAR
517	mfspr	r11,SPRN_SRR1
518	crset	4*cr6+eq
519	BRANCH_TO_COMMON(r10, slb_miss_common)
520EXC_REAL_END(data_access_slb, 0x380, 0x80)
521
522EXC_VIRT_BEGIN(data_access_slb, 0x4380, 0x80)
523	SET_SCRATCH0(r13)
524	EXCEPTION_PROLOG_0(PACA_EXSLB)
525	EXCEPTION_PROLOG_1(PACA_EXSLB, NOTEST, 0x380)
526	mr	r12,r3	/* save r3 */
527	mfspr	r3,SPRN_DAR
528	mfspr	r11,SPRN_SRR1
529	crset	4*cr6+eq
530	BRANCH_TO_COMMON(r10, slb_miss_common)
531EXC_VIRT_END(data_access_slb, 0x4380, 0x80)
532TRAMP_KVM_SKIP(PACA_EXSLB, 0x380)
533
534
535EXC_REAL(instruction_access, 0x400, 0x80)
536EXC_VIRT(instruction_access, 0x4400, 0x80, 0x400)
537TRAMP_KVM(PACA_EXGEN, 0x400)
538
539EXC_COMMON_BEGIN(instruction_access_common)
540	EXCEPTION_PROLOG_COMMON(0x400, PACA_EXGEN)
541	RECONCILE_IRQ_STATE(r10, r11)
542	ld	r12,_MSR(r1)
543	ld	r3,_NIP(r1)
544	andis.	r4,r12,0x5820
545	li	r5,0x400
546	std	r3,_DAR(r1)
547	std	r4,_DSISR(r1)
548BEGIN_MMU_FTR_SECTION
549	b	do_hash_page		/* Try to handle as hpte fault */
550MMU_FTR_SECTION_ELSE
551	b	handle_page_fault
552ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)
553
554
555EXC_REAL_BEGIN(instruction_access_slb, 0x480, 0x80)
556	SET_SCRATCH0(r13)
557	EXCEPTION_PROLOG_0(PACA_EXSLB)
558	EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST_PR, 0x480)
559	mr	r12,r3	/* save r3 */
560	mfspr	r3,SPRN_SRR0		/* SRR0 is faulting address */
561	mfspr	r11,SPRN_SRR1
562	crclr	4*cr6+eq
563	BRANCH_TO_COMMON(r10, slb_miss_common)
564EXC_REAL_END(instruction_access_slb, 0x480, 0x80)
565
566EXC_VIRT_BEGIN(instruction_access_slb, 0x4480, 0x80)
567	SET_SCRATCH0(r13)
568	EXCEPTION_PROLOG_0(PACA_EXSLB)
569	EXCEPTION_PROLOG_1(PACA_EXSLB, NOTEST, 0x480)
570	mr	r12,r3	/* save r3 */
571	mfspr	r3,SPRN_SRR0		/* SRR0 is faulting address */
572	mfspr	r11,SPRN_SRR1
573	crclr	4*cr6+eq
574	BRANCH_TO_COMMON(r10, slb_miss_common)
575EXC_VIRT_END(instruction_access_slb, 0x4480, 0x80)
576TRAMP_KVM(PACA_EXSLB, 0x480)
577
578
579/*
580 * This handler is used by the 0x380 and 0x480 SLB miss interrupts, as well as
581 * the virtual mode 0x4380 and 0x4480 interrupts if AIL is enabled.
582 */
583EXC_COMMON_BEGIN(slb_miss_common)
584	/*
585	 * r13 points to the PACA, r9 contains the saved CR,
586	 * r12 contains the saved r3,
587	 * r11 contain the saved SRR1, SRR0 is still ready for return
588	 * r3 has the faulting address
589	 * r9 - r13 are saved in paca->exslb.
590 	 * cr6.eq is set for a D-SLB miss, clear for a I-SLB miss
591	 * We assume we aren't going to take any exceptions during this
592	 * procedure.
593	 */
594	mflr	r10
595	stw	r9,PACA_EXSLB+EX_CCR(r13)	/* save CR in exc. frame */
596	std	r10,PACA_EXSLB+EX_LR(r13)	/* save LR */
597
598	/*
599	 * Test MSR_RI before calling slb_allocate_realmode, because the
600	 * MSR in r11 gets clobbered. However we still want to allocate
601	 * SLB in case MSR_RI=0, to minimise the risk of getting stuck in
602	 * recursive SLB faults. So use cr5 for this, which is preserved.
603	 */
604	andi.	r11,r11,MSR_RI	/* check for unrecoverable exception */
605	cmpdi	cr5,r11,MSR_RI
606
607	crset	4*cr0+eq
608#ifdef CONFIG_PPC_STD_MMU_64
609BEGIN_MMU_FTR_SECTION
610	bl	slb_allocate
611END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX)
612#endif
613
614	ld	r10,PACA_EXSLB+EX_LR(r13)
615	lwz	r9,PACA_EXSLB+EX_CCR(r13)	/* get saved CR */
616	mtlr	r10
617
618	beq-	8f		/* if bad address, make full stack frame */
619
620	bne-	cr5,2f		/* if unrecoverable exception, oops */
621
622	/* All done -- return from exception. */
623
624.machine	push
625.machine	"power4"
626	mtcrf	0x80,r9
627	mtcrf	0x04,r9		/* MSR[RI] indication is in cr5 */
628	mtcrf	0x02,r9		/* I/D indication is in cr6 */
629	mtcrf	0x01,r9		/* slb_allocate uses cr0 and cr7 */
630.machine	pop
631
632	RESTORE_CTR(r9, PACA_EXSLB)
633	RESTORE_PPR_PACA(PACA_EXSLB, r9)
634	mr	r3,r12
635	ld	r9,PACA_EXSLB+EX_R9(r13)
636	ld	r10,PACA_EXSLB+EX_R10(r13)
637	ld	r11,PACA_EXSLB+EX_R11(r13)
638	ld	r12,PACA_EXSLB+EX_R12(r13)
639	ld	r13,PACA_EXSLB+EX_R13(r13)
640	rfid
641	b	.	/* prevent speculative execution */
642
6432:	std     r3,PACA_EXSLB+EX_DAR(r13)
644	mr	r3,r12
645	mfspr	r11,SPRN_SRR0
646	mfspr	r12,SPRN_SRR1
647	LOAD_HANDLER(r10,unrecov_slb)
648	mtspr	SPRN_SRR0,r10
649	ld	r10,PACAKMSR(r13)
650	mtspr	SPRN_SRR1,r10
651	rfid
652	b	.
653
6548:	std     r3,PACA_EXSLB+EX_DAR(r13)
655	mr	r3,r12
656	mfspr	r11,SPRN_SRR0
657	mfspr	r12,SPRN_SRR1
658	LOAD_HANDLER(r10,bad_addr_slb)
659	mtspr	SPRN_SRR0,r10
660	ld	r10,PACAKMSR(r13)
661	mtspr	SPRN_SRR1,r10
662	rfid
663	b	.
664
665EXC_COMMON_BEGIN(unrecov_slb)
666	EXCEPTION_PROLOG_COMMON(0x4100, PACA_EXSLB)
667	RECONCILE_IRQ_STATE(r10, r11)
668	bl	save_nvgprs
6691:	addi	r3,r1,STACK_FRAME_OVERHEAD
670	bl	unrecoverable_exception
671	b	1b
672
673EXC_COMMON_BEGIN(bad_addr_slb)
674	EXCEPTION_PROLOG_COMMON(0x380, PACA_EXSLB)
675	RECONCILE_IRQ_STATE(r10, r11)
676	ld	r3, PACA_EXSLB+EX_DAR(r13)
677	std	r3, _DAR(r1)
678	beq	cr6, 2f
679	li	r10, 0x480		/* fix trap number for I-SLB miss */
680	std	r10, _TRAP(r1)
6812:	bl	save_nvgprs
682	addi	r3, r1, STACK_FRAME_OVERHEAD
683	bl	slb_miss_bad_addr
684	b	ret_from_except
685
686EXC_REAL_BEGIN(hardware_interrupt, 0x500, 0x100)
687	.globl hardware_interrupt_hv;
688hardware_interrupt_hv:
689	BEGIN_FTR_SECTION
690		_MASKABLE_EXCEPTION_PSERIES(0x500, hardware_interrupt_common,
691					    EXC_HV, SOFTEN_TEST_HV)
692	FTR_SECTION_ELSE
693		_MASKABLE_EXCEPTION_PSERIES(0x500, hardware_interrupt_common,
694					    EXC_STD, SOFTEN_TEST_PR)
695	ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
696EXC_REAL_END(hardware_interrupt, 0x500, 0x100)
697
698EXC_VIRT_BEGIN(hardware_interrupt, 0x4500, 0x100)
699	.globl hardware_interrupt_relon_hv;
700hardware_interrupt_relon_hv:
701	BEGIN_FTR_SECTION
702		_MASKABLE_RELON_EXCEPTION_PSERIES(0x500, hardware_interrupt_common, EXC_HV, SOFTEN_TEST_HV)
703	FTR_SECTION_ELSE
704		_MASKABLE_RELON_EXCEPTION_PSERIES(0x500, hardware_interrupt_common, EXC_STD, SOFTEN_TEST_PR)
705	ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
706EXC_VIRT_END(hardware_interrupt, 0x4500, 0x100)
707
708TRAMP_KVM(PACA_EXGEN, 0x500)
709TRAMP_KVM_HV(PACA_EXGEN, 0x500)
710EXC_COMMON_ASYNC(hardware_interrupt_common, 0x500, do_IRQ)
711
712
713EXC_REAL(alignment, 0x600, 0x100)
714EXC_VIRT(alignment, 0x4600, 0x100, 0x600)
715TRAMP_KVM(PACA_EXGEN, 0x600)
716EXC_COMMON_BEGIN(alignment_common)
717	mfspr	r10,SPRN_DAR
718	std	r10,PACA_EXGEN+EX_DAR(r13)
719	mfspr	r10,SPRN_DSISR
720	stw	r10,PACA_EXGEN+EX_DSISR(r13)
721	EXCEPTION_PROLOG_COMMON(0x600, PACA_EXGEN)
722	ld	r3,PACA_EXGEN+EX_DAR(r13)
723	lwz	r4,PACA_EXGEN+EX_DSISR(r13)
724	std	r3,_DAR(r1)
725	std	r4,_DSISR(r1)
726	bl	save_nvgprs
727	RECONCILE_IRQ_STATE(r10, r11)
728	addi	r3,r1,STACK_FRAME_OVERHEAD
729	bl	alignment_exception
730	b	ret_from_except
731
732
733EXC_REAL(program_check, 0x700, 0x100)
734EXC_VIRT(program_check, 0x4700, 0x100, 0x700)
735TRAMP_KVM(PACA_EXGEN, 0x700)
736EXC_COMMON_BEGIN(program_check_common)
737	EXCEPTION_PROLOG_COMMON(0x700, PACA_EXGEN)
738	bl	save_nvgprs
739	RECONCILE_IRQ_STATE(r10, r11)
740	addi	r3,r1,STACK_FRAME_OVERHEAD
741	bl	program_check_exception
742	b	ret_from_except
743
744
745EXC_REAL(fp_unavailable, 0x800, 0x100)
746EXC_VIRT(fp_unavailable, 0x4800, 0x100, 0x800)
747TRAMP_KVM(PACA_EXGEN, 0x800)
748EXC_COMMON_BEGIN(fp_unavailable_common)
749	EXCEPTION_PROLOG_COMMON(0x800, PACA_EXGEN)
750	bne	1f			/* if from user, just load it up */
751	bl	save_nvgprs
752	RECONCILE_IRQ_STATE(r10, r11)
753	addi	r3,r1,STACK_FRAME_OVERHEAD
754	bl	kernel_fp_unavailable_exception
755	BUG_OPCODE
7561:
757#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
758BEGIN_FTR_SECTION
759	/* Test if 2 TM state bits are zero.  If non-zero (ie. userspace was in
760	 * transaction), go do TM stuff
761	 */
762	rldicl.	r0, r12, (64-MSR_TS_LG), (64-2)
763	bne-	2f
764END_FTR_SECTION_IFSET(CPU_FTR_TM)
765#endif
766	bl	load_up_fpu
767	b	fast_exception_return
768#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
7692:	/* User process was in a transaction */
770	bl	save_nvgprs
771	RECONCILE_IRQ_STATE(r10, r11)
772	addi	r3,r1,STACK_FRAME_OVERHEAD
773	bl	fp_unavailable_tm
774	b	ret_from_except
775#endif
776
777
778EXC_REAL_MASKABLE(decrementer, 0x900, 0x80)
779EXC_VIRT_MASKABLE(decrementer, 0x4900, 0x80, 0x900)
780TRAMP_KVM(PACA_EXGEN, 0x900)
781EXC_COMMON_ASYNC(decrementer_common, 0x900, timer_interrupt)
782
783
784EXC_REAL_HV(hdecrementer, 0x980, 0x80)
785EXC_VIRT_HV(hdecrementer, 0x4980, 0x80, 0x980)
786TRAMP_KVM_HV(PACA_EXGEN, 0x980)
787EXC_COMMON(hdecrementer_common, 0x980, hdec_interrupt)
788
789
790EXC_REAL_MASKABLE(doorbell_super, 0xa00, 0x100)
791EXC_VIRT_MASKABLE(doorbell_super, 0x4a00, 0x100, 0xa00)
792TRAMP_KVM(PACA_EXGEN, 0xa00)
793#ifdef CONFIG_PPC_DOORBELL
794EXC_COMMON_ASYNC(doorbell_super_common, 0xa00, doorbell_exception)
795#else
796EXC_COMMON_ASYNC(doorbell_super_common, 0xa00, unknown_exception)
797#endif
798
799
800EXC_REAL(trap_0b, 0xb00, 0x100)
801EXC_VIRT(trap_0b, 0x4b00, 0x100, 0xb00)
802TRAMP_KVM(PACA_EXGEN, 0xb00)
803EXC_COMMON(trap_0b_common, 0xb00, unknown_exception)
804
805/*
806 * system call / hypercall (0xc00, 0x4c00)
807 *
808 * The system call exception is invoked with "sc 0" and does not alter HV bit.
809 * There is support for kernel code to invoke system calls but there are no
810 * in-tree users.
811 *
812 * The hypercall is invoked with "sc 1" and sets HV=1.
813 *
814 * In HPT, sc 1 always goes to 0xc00 real mode. In RADIX, sc 1 can go to
815 * 0x4c00 virtual mode.
816 *
817 * Call convention:
818 *
819 * syscall register convention is in Documentation/powerpc/syscall64-abi.txt
820 *
821 * For hypercalls, the register convention is as follows:
822 * r0 volatile
823 * r1-2 nonvolatile
824 * r3 volatile parameter and return value for status
825 * r4-r10 volatile input and output value
826 * r11 volatile hypercall number and output value
827 * r12 volatile input and output value
828 * r13-r31 nonvolatile
829 * LR nonvolatile
830 * CTR volatile
831 * XER volatile
832 * CR0-1 CR5-7 volatile
833 * CR2-4 nonvolatile
834 * Other registers nonvolatile
835 *
836 * The intersection of volatile registers that don't contain possible
837 * inputs is: cr0, xer, ctr. We may use these as scratch regs upon entry
838 * without saving, though xer is not a good idea to use, as hardware may
839 * interpret some bits so it may be costly to change them.
840 */
841#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
842	/*
843	 * There is a little bit of juggling to get syscall and hcall
844	 * working well. Save r13 in ctr to avoid using SPRG scratch
845	 * register.
846	 *
847	 * Userspace syscalls have already saved the PPR, hcalls must save
848	 * it before setting HMT_MEDIUM.
849	 */
850#define SYSCALL_KVMTEST							\
851	mtctr	r13;							\
852	GET_PACA(r13);							\
853	std	r10,PACA_EXGEN+EX_R10(r13);				\
854	KVMTEST_PR(0xc00); /* uses r10, branch to do_kvm_0xc00_system_call */ \
855	HMT_MEDIUM;							\
856	mfctr	r9;
857
858#else
859#define SYSCALL_KVMTEST							\
860	HMT_MEDIUM;							\
861	mr	r9,r13;							\
862	GET_PACA(r13);
863#endif
864
865#define LOAD_SYSCALL_HANDLER(reg)					\
866	__LOAD_HANDLER(reg, system_call_common)
867
868#define SYSCALL_FASTENDIAN_TEST					\
869BEGIN_FTR_SECTION						\
870	cmpdi	r0,0x1ebe ; 					\
871	beq-	1f ;						\
872END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE)				\
873
874/*
875 * After SYSCALL_KVMTEST, we reach here with PACA in r13, r13 in r9,
876 * and HMT_MEDIUM.
877 */
878#define SYSCALL_REAL	 					\
879	mfspr	r11,SPRN_SRR0 ;					\
880	mfspr	r12,SPRN_SRR1 ;					\
881	LOAD_SYSCALL_HANDLER(r10) ; 				\
882	mtspr	SPRN_SRR0,r10 ; 				\
883	ld	r10,PACAKMSR(r13) ;				\
884	mtspr	SPRN_SRR1,r10 ; 				\
885	rfid ; 							\
886	b	. ;	/* prevent speculative execution */
887
888#define SYSCALL_FASTENDIAN					\
889	/* Fast LE/BE switch system call */			\
8901:	mfspr	r12,SPRN_SRR1 ;					\
891	xori	r12,r12,MSR_LE ;				\
892	mtspr	SPRN_SRR1,r12 ;					\
893	mr	r13,r9 ;					\
894	rfid ;		/* return to userspace */		\
895	b	. ;	/* prevent speculative execution */
896
897#if defined(CONFIG_RELOCATABLE)
898	/*
899	 * We can't branch directly so we do it via the CTR which
900	 * is volatile across system calls.
901	 */
902#define SYSCALL_VIRT						\
903	LOAD_SYSCALL_HANDLER(r10) ;				\
904	mtctr	r10 ;						\
905	mfspr	r11,SPRN_SRR0 ;					\
906	mfspr	r12,SPRN_SRR1 ;					\
907	li	r10,MSR_RI ;					\
908	mtmsrd 	r10,1 ;						\
909	bctr ;
910#else
911	/* We can branch directly */
912#define SYSCALL_VIRT						\
913	mfspr	r11,SPRN_SRR0 ;					\
914	mfspr	r12,SPRN_SRR1 ;					\
915	li	r10,MSR_RI ;					\
916	mtmsrd 	r10,1 ;			/* Set RI (EE=0) */	\
917	b	system_call_common ;
918#endif
919
920EXC_REAL_BEGIN(system_call, 0xc00, 0x100)
921	SYSCALL_KVMTEST /* loads PACA into r13, and saves r13 to r9 */
922	SYSCALL_FASTENDIAN_TEST
923	SYSCALL_REAL
924	SYSCALL_FASTENDIAN
925EXC_REAL_END(system_call, 0xc00, 0x100)
926
927EXC_VIRT_BEGIN(system_call, 0x4c00, 0x100)
928	SYSCALL_KVMTEST /* loads PACA into r13, and saves r13 to r9 */
929	SYSCALL_FASTENDIAN_TEST
930	SYSCALL_VIRT
931	SYSCALL_FASTENDIAN
932EXC_VIRT_END(system_call, 0x4c00, 0x100)
933
934#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
935	/*
936	 * This is a hcall, so register convention is as above, with these
937	 * differences:
938	 * r13 = PACA
939	 * ctr = orig r13
940	 * orig r10 saved in PACA
941	 */
942TRAMP_KVM_BEGIN(do_kvm_0xc00)
943	 /*
944	  * Save the PPR (on systems that support it) before changing to
945	  * HMT_MEDIUM. That allows the KVM code to save that value into the
946	  * guest state (it is the guest's PPR value).
947	  */
948	OPT_GET_SPR(r10, SPRN_PPR, CPU_FTR_HAS_PPR)
949	HMT_MEDIUM
950	OPT_SAVE_REG_TO_PACA(PACA_EXGEN+EX_PPR, r10, CPU_FTR_HAS_PPR)
951	mfctr	r10
952	SET_SCRATCH0(r10)
953	std	r9,PACA_EXGEN+EX_R9(r13)
954	mfcr	r9
955	KVM_HANDLER(PACA_EXGEN, EXC_STD, 0xc00)
956#endif
957
958
959EXC_REAL(single_step, 0xd00, 0x100)
960EXC_VIRT(single_step, 0x4d00, 0x100, 0xd00)
961TRAMP_KVM(PACA_EXGEN, 0xd00)
962EXC_COMMON(single_step_common, 0xd00, single_step_exception)
963
964EXC_REAL_OOL_HV(h_data_storage, 0xe00, 0x20)
965EXC_VIRT_OOL_HV(h_data_storage, 0x4e00, 0x20, 0xe00)
966TRAMP_KVM_HV_SKIP(PACA_EXGEN, 0xe00)
967EXC_COMMON_BEGIN(h_data_storage_common)
968	mfspr   r10,SPRN_HDAR
969	std     r10,PACA_EXGEN+EX_DAR(r13)
970	mfspr   r10,SPRN_HDSISR
971	stw     r10,PACA_EXGEN+EX_DSISR(r13)
972	EXCEPTION_PROLOG_COMMON(0xe00, PACA_EXGEN)
973	bl      save_nvgprs
974	RECONCILE_IRQ_STATE(r10, r11)
975	addi    r3,r1,STACK_FRAME_OVERHEAD
976	bl      unknown_exception
977	b       ret_from_except
978
979
980EXC_REAL_OOL_HV(h_instr_storage, 0xe20, 0x20)
981EXC_VIRT_OOL_HV(h_instr_storage, 0x4e20, 0x20, 0xe20)
982TRAMP_KVM_HV(PACA_EXGEN, 0xe20)
983EXC_COMMON(h_instr_storage_common, 0xe20, unknown_exception)
984
985
986EXC_REAL_OOL_HV(emulation_assist, 0xe40, 0x20)
987EXC_VIRT_OOL_HV(emulation_assist, 0x4e40, 0x20, 0xe40)
988TRAMP_KVM_HV(PACA_EXGEN, 0xe40)
989EXC_COMMON(emulation_assist_common, 0xe40, emulation_assist_interrupt)
990
991
992/*
993 * hmi_exception trampoline is a special case. It jumps to hmi_exception_early
994 * first, and then eventaully from there to the trampoline to get into virtual
995 * mode.
996 */
997__EXC_REAL_OOL_HV_DIRECT(hmi_exception, 0xe60, 0x20, hmi_exception_early)
998__TRAMP_REAL_OOL_MASKABLE_HV(hmi_exception, 0xe60)
999EXC_VIRT_NONE(0x4e60, 0x20)
1000TRAMP_KVM_HV(PACA_EXGEN, 0xe60)
1001TRAMP_REAL_BEGIN(hmi_exception_early)
1002	EXCEPTION_PROLOG_1(PACA_EXGEN, KVMTEST_HV, 0xe60)
1003	mr	r10,r1			/* Save r1 */
1004	ld	r1,PACAEMERGSP(r13)	/* Use emergency stack for realmode */
1005	subi	r1,r1,INT_FRAME_SIZE	/* alloc stack frame		*/
1006	mfspr	r11,SPRN_HSRR0		/* Save HSRR0 */
1007	mfspr	r12,SPRN_HSRR1		/* Save HSRR1 */
1008	EXCEPTION_PROLOG_COMMON_1()
1009	EXCEPTION_PROLOG_COMMON_2(PACA_EXGEN)
1010	EXCEPTION_PROLOG_COMMON_3(0xe60)
1011	addi	r3,r1,STACK_FRAME_OVERHEAD
1012	BRANCH_LINK_TO_FAR(hmi_exception_realmode) /* Function call ABI */
1013	/* Windup the stack. */
1014	/* Move original HSRR0 and HSRR1 into the respective regs */
1015	ld	r9,_MSR(r1)
1016	mtspr	SPRN_HSRR1,r9
1017	ld	r3,_NIP(r1)
1018	mtspr	SPRN_HSRR0,r3
1019	ld	r9,_CTR(r1)
1020	mtctr	r9
1021	ld	r9,_XER(r1)
1022	mtxer	r9
1023	ld	r9,_LINK(r1)
1024	mtlr	r9
1025	REST_GPR(0, r1)
1026	REST_8GPRS(2, r1)
1027	REST_GPR(10, r1)
1028	ld	r11,_CCR(r1)
1029	mtcr	r11
1030	REST_GPR(11, r1)
1031	REST_2GPRS(12, r1)
1032	/* restore original r1. */
1033	ld	r1,GPR1(r1)
1034
1035	/*
1036	 * Go to virtual mode and pull the HMI event information from
1037	 * firmware.
1038	 */
1039	.globl hmi_exception_after_realmode
1040hmi_exception_after_realmode:
1041	SET_SCRATCH0(r13)
1042	EXCEPTION_PROLOG_0(PACA_EXGEN)
1043	b	tramp_real_hmi_exception
1044
1045EXC_COMMON_ASYNC(hmi_exception_common, 0xe60, handle_hmi_exception)
1046
1047
1048EXC_REAL_OOL_MASKABLE_HV(h_doorbell, 0xe80, 0x20)
1049EXC_VIRT_OOL_MASKABLE_HV(h_doorbell, 0x4e80, 0x20, 0xe80)
1050TRAMP_KVM_HV(PACA_EXGEN, 0xe80)
1051#ifdef CONFIG_PPC_DOORBELL
1052EXC_COMMON_ASYNC(h_doorbell_common, 0xe80, doorbell_exception)
1053#else
1054EXC_COMMON_ASYNC(h_doorbell_common, 0xe80, unknown_exception)
1055#endif
1056
1057
1058EXC_REAL_OOL_MASKABLE_HV(h_virt_irq, 0xea0, 0x20)
1059EXC_VIRT_OOL_MASKABLE_HV(h_virt_irq, 0x4ea0, 0x20, 0xea0)
1060TRAMP_KVM_HV(PACA_EXGEN, 0xea0)
1061EXC_COMMON_ASYNC(h_virt_irq_common, 0xea0, do_IRQ)
1062
1063
1064EXC_REAL_NONE(0xec0, 0x20)
1065EXC_VIRT_NONE(0x4ec0, 0x20)
1066EXC_REAL_NONE(0xee0, 0x20)
1067EXC_VIRT_NONE(0x4ee0, 0x20)
1068
1069
1070EXC_REAL_OOL(performance_monitor, 0xf00, 0x20)
1071EXC_VIRT_OOL(performance_monitor, 0x4f00, 0x20, 0xf00)
1072TRAMP_KVM(PACA_EXGEN, 0xf00)
1073EXC_COMMON_ASYNC(performance_monitor_common, 0xf00, performance_monitor_exception)
1074
1075
1076EXC_REAL_OOL(altivec_unavailable, 0xf20, 0x20)
1077EXC_VIRT_OOL(altivec_unavailable, 0x4f20, 0x20, 0xf20)
1078TRAMP_KVM(PACA_EXGEN, 0xf20)
1079EXC_COMMON_BEGIN(altivec_unavailable_common)
1080	EXCEPTION_PROLOG_COMMON(0xf20, PACA_EXGEN)
1081#ifdef CONFIG_ALTIVEC
1082BEGIN_FTR_SECTION
1083	beq	1f
1084#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1085  BEGIN_FTR_SECTION_NESTED(69)
1086	/* Test if 2 TM state bits are zero.  If non-zero (ie. userspace was in
1087	 * transaction), go do TM stuff
1088	 */
1089	rldicl.	r0, r12, (64-MSR_TS_LG), (64-2)
1090	bne-	2f
1091  END_FTR_SECTION_NESTED(CPU_FTR_TM, CPU_FTR_TM, 69)
1092#endif
1093	bl	load_up_altivec
1094	b	fast_exception_return
1095#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
10962:	/* User process was in a transaction */
1097	bl	save_nvgprs
1098	RECONCILE_IRQ_STATE(r10, r11)
1099	addi	r3,r1,STACK_FRAME_OVERHEAD
1100	bl	altivec_unavailable_tm
1101	b	ret_from_except
1102#endif
11031:
1104END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
1105#endif
1106	bl	save_nvgprs
1107	RECONCILE_IRQ_STATE(r10, r11)
1108	addi	r3,r1,STACK_FRAME_OVERHEAD
1109	bl	altivec_unavailable_exception
1110	b	ret_from_except
1111
1112
1113EXC_REAL_OOL(vsx_unavailable, 0xf40, 0x20)
1114EXC_VIRT_OOL(vsx_unavailable, 0x4f40, 0x20, 0xf40)
1115TRAMP_KVM(PACA_EXGEN, 0xf40)
1116EXC_COMMON_BEGIN(vsx_unavailable_common)
1117	EXCEPTION_PROLOG_COMMON(0xf40, PACA_EXGEN)
1118#ifdef CONFIG_VSX
1119BEGIN_FTR_SECTION
1120	beq	1f
1121#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1122  BEGIN_FTR_SECTION_NESTED(69)
1123	/* Test if 2 TM state bits are zero.  If non-zero (ie. userspace was in
1124	 * transaction), go do TM stuff
1125	 */
1126	rldicl.	r0, r12, (64-MSR_TS_LG), (64-2)
1127	bne-	2f
1128  END_FTR_SECTION_NESTED(CPU_FTR_TM, CPU_FTR_TM, 69)
1129#endif
1130	b	load_up_vsx
1131#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
11322:	/* User process was in a transaction */
1133	bl	save_nvgprs
1134	RECONCILE_IRQ_STATE(r10, r11)
1135	addi	r3,r1,STACK_FRAME_OVERHEAD
1136	bl	vsx_unavailable_tm
1137	b	ret_from_except
1138#endif
11391:
1140END_FTR_SECTION_IFSET(CPU_FTR_VSX)
1141#endif
1142	bl	save_nvgprs
1143	RECONCILE_IRQ_STATE(r10, r11)
1144	addi	r3,r1,STACK_FRAME_OVERHEAD
1145	bl	vsx_unavailable_exception
1146	b	ret_from_except
1147
1148
1149EXC_REAL_OOL(facility_unavailable, 0xf60, 0x20)
1150EXC_VIRT_OOL(facility_unavailable, 0x4f60, 0x20, 0xf60)
1151TRAMP_KVM(PACA_EXGEN, 0xf60)
1152EXC_COMMON(facility_unavailable_common, 0xf60, facility_unavailable_exception)
1153
1154
1155EXC_REAL_OOL_HV(h_facility_unavailable, 0xf80, 0x20)
1156EXC_VIRT_OOL_HV(h_facility_unavailable, 0x4f80, 0x20, 0xf80)
1157TRAMP_KVM_HV(PACA_EXGEN, 0xf80)
1158EXC_COMMON(h_facility_unavailable_common, 0xf80, facility_unavailable_exception)
1159
1160
1161EXC_REAL_NONE(0xfa0, 0x20)
1162EXC_VIRT_NONE(0x4fa0, 0x20)
1163EXC_REAL_NONE(0xfc0, 0x20)
1164EXC_VIRT_NONE(0x4fc0, 0x20)
1165EXC_REAL_NONE(0xfe0, 0x20)
1166EXC_VIRT_NONE(0x4fe0, 0x20)
1167
1168EXC_REAL_NONE(0x1000, 0x100)
1169EXC_VIRT_NONE(0x5000, 0x100)
1170EXC_REAL_NONE(0x1100, 0x100)
1171EXC_VIRT_NONE(0x5100, 0x100)
1172
1173#ifdef CONFIG_CBE_RAS
1174EXC_REAL_HV(cbe_system_error, 0x1200, 0x100)
1175EXC_VIRT_NONE(0x5200, 0x100)
1176TRAMP_KVM_HV_SKIP(PACA_EXGEN, 0x1200)
1177EXC_COMMON(cbe_system_error_common, 0x1200, cbe_system_error_exception)
1178#else /* CONFIG_CBE_RAS */
1179EXC_REAL_NONE(0x1200, 0x100)
1180EXC_VIRT_NONE(0x5200, 0x100)
1181#endif
1182
1183
1184EXC_REAL(instruction_breakpoint, 0x1300, 0x100)
1185EXC_VIRT(instruction_breakpoint, 0x5300, 0x100, 0x1300)
1186TRAMP_KVM_SKIP(PACA_EXGEN, 0x1300)
1187EXC_COMMON(instruction_breakpoint_common, 0x1300, instruction_breakpoint_exception)
1188
1189EXC_REAL_NONE(0x1400, 0x100)
1190EXC_VIRT_NONE(0x5400, 0x100)
1191
1192EXC_REAL_BEGIN(denorm_exception_hv, 0x1500, 0x100)
1193	mtspr	SPRN_SPRG_HSCRATCH0,r13
1194	EXCEPTION_PROLOG_0(PACA_EXGEN)
1195	EXCEPTION_PROLOG_1(PACA_EXGEN, NOTEST, 0x1500)
1196
1197#ifdef CONFIG_PPC_DENORMALISATION
1198	mfspr	r10,SPRN_HSRR1
1199	mfspr	r11,SPRN_HSRR0		/* save HSRR0 */
1200	andis.	r10,r10,(HSRR1_DENORM)@h /* denorm? */
1201	addi	r11,r11,-4		/* HSRR0 is next instruction */
1202	bne+	denorm_assist
1203#endif
1204
1205	KVMTEST_PR(0x1500)
1206	EXCEPTION_PROLOG_PSERIES_1(denorm_common, EXC_HV)
1207EXC_REAL_END(denorm_exception_hv, 0x1500, 0x100)
1208
1209#ifdef CONFIG_PPC_DENORMALISATION
1210EXC_VIRT_BEGIN(denorm_exception, 0x5500, 0x100)
1211	b	exc_real_0x1500_denorm_exception_hv
1212EXC_VIRT_END(denorm_exception, 0x5500, 0x100)
1213#else
1214EXC_VIRT_NONE(0x5500, 0x100)
1215#endif
1216
1217TRAMP_KVM_SKIP(PACA_EXGEN, 0x1500)
1218
1219#ifdef CONFIG_PPC_DENORMALISATION
1220TRAMP_REAL_BEGIN(denorm_assist)
1221BEGIN_FTR_SECTION
1222/*
1223 * To denormalise we need to move a copy of the register to itself.
1224 * For POWER6 do that here for all FP regs.
1225 */
1226	mfmsr	r10
1227	ori	r10,r10,(MSR_FP|MSR_FE0|MSR_FE1)
1228	xori	r10,r10,(MSR_FE0|MSR_FE1)
1229	mtmsrd	r10
1230	sync
1231
1232#define FMR2(n)  fmr (n), (n) ; fmr n+1, n+1
1233#define FMR4(n)  FMR2(n) ; FMR2(n+2)
1234#define FMR8(n)  FMR4(n) ; FMR4(n+4)
1235#define FMR16(n) FMR8(n) ; FMR8(n+8)
1236#define FMR32(n) FMR16(n) ; FMR16(n+16)
1237	FMR32(0)
1238
1239FTR_SECTION_ELSE
1240/*
1241 * To denormalise we need to move a copy of the register to itself.
1242 * For POWER7 do that here for the first 32 VSX registers only.
1243 */
1244	mfmsr	r10
1245	oris	r10,r10,MSR_VSX@h
1246	mtmsrd	r10
1247	sync
1248
1249#define XVCPSGNDP2(n) XVCPSGNDP(n,n,n) ; XVCPSGNDP(n+1,n+1,n+1)
1250#define XVCPSGNDP4(n) XVCPSGNDP2(n) ; XVCPSGNDP2(n+2)
1251#define XVCPSGNDP8(n) XVCPSGNDP4(n) ; XVCPSGNDP4(n+4)
1252#define XVCPSGNDP16(n) XVCPSGNDP8(n) ; XVCPSGNDP8(n+8)
1253#define XVCPSGNDP32(n) XVCPSGNDP16(n) ; XVCPSGNDP16(n+16)
1254	XVCPSGNDP32(0)
1255
1256ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_206)
1257
1258BEGIN_FTR_SECTION
1259	b	denorm_done
1260END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
1261/*
1262 * To denormalise we need to move a copy of the register to itself.
1263 * For POWER8 we need to do that for all 64 VSX registers
1264 */
1265	XVCPSGNDP32(32)
1266denorm_done:
1267	mtspr	SPRN_HSRR0,r11
1268	mtcrf	0x80,r9
1269	ld	r9,PACA_EXGEN+EX_R9(r13)
1270	RESTORE_PPR_PACA(PACA_EXGEN, r10)
1271BEGIN_FTR_SECTION
1272	ld	r10,PACA_EXGEN+EX_CFAR(r13)
1273	mtspr	SPRN_CFAR,r10
1274END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
1275	ld	r10,PACA_EXGEN+EX_R10(r13)
1276	ld	r11,PACA_EXGEN+EX_R11(r13)
1277	ld	r12,PACA_EXGEN+EX_R12(r13)
1278	ld	r13,PACA_EXGEN+EX_R13(r13)
1279	HRFID
1280	b	.
1281#endif
1282
1283EXC_COMMON_HV(denorm_common, 0x1500, unknown_exception)
1284
1285
1286#ifdef CONFIG_CBE_RAS
1287EXC_REAL_HV(cbe_maintenance, 0x1600, 0x100)
1288EXC_VIRT_NONE(0x5600, 0x100)
1289TRAMP_KVM_HV_SKIP(PACA_EXGEN, 0x1600)
1290EXC_COMMON(cbe_maintenance_common, 0x1600, cbe_maintenance_exception)
1291#else /* CONFIG_CBE_RAS */
1292EXC_REAL_NONE(0x1600, 0x100)
1293EXC_VIRT_NONE(0x5600, 0x100)
1294#endif
1295
1296
1297EXC_REAL(altivec_assist, 0x1700, 0x100)
1298EXC_VIRT(altivec_assist, 0x5700, 0x100, 0x1700)
1299TRAMP_KVM(PACA_EXGEN, 0x1700)
1300#ifdef CONFIG_ALTIVEC
1301EXC_COMMON(altivec_assist_common, 0x1700, altivec_assist_exception)
1302#else
1303EXC_COMMON(altivec_assist_common, 0x1700, unknown_exception)
1304#endif
1305
1306
1307#ifdef CONFIG_CBE_RAS
1308EXC_REAL_HV(cbe_thermal, 0x1800, 0x100)
1309EXC_VIRT_NONE(0x5800, 0x100)
1310TRAMP_KVM_HV_SKIP(PACA_EXGEN, 0x1800)
1311EXC_COMMON(cbe_thermal_common, 0x1800, cbe_thermal_exception)
1312#else /* CONFIG_CBE_RAS */
1313EXC_REAL_NONE(0x1800, 0x100)
1314EXC_VIRT_NONE(0x5800, 0x100)
1315#endif
1316
1317#if defined(CONFIG_HARDLOCKUP_DETECTOR) && defined(CONFIG_HAVE_HARDLOCKUP_DETECTOR_ARCH)
1318
1319#define MASKED_DEC_HANDLER_LABEL 3f
1320
1321#define MASKED_DEC_HANDLER(_H)				\
13223: /* soft-nmi */					\
1323	std	r12,PACA_EXGEN+EX_R12(r13);		\
1324	GET_SCRATCH0(r10);				\
1325	std	r10,PACA_EXGEN+EX_R13(r13);		\
1326	EXCEPTION_PROLOG_PSERIES_1(soft_nmi_common, _H)
1327
1328/*
1329 * Branch to soft_nmi_interrupt using the emergency stack. The emergency
1330 * stack is one that is usable by maskable interrupts so long as MSR_EE
1331 * remains off. It is used for recovery when something has corrupted the
1332 * normal kernel stack, for example. The "soft NMI" must not use the process
1333 * stack because we want irq disabled sections to avoid touching the stack
1334 * at all (other than PMU interrupts), so use the emergency stack for this,
1335 * and run it entirely with interrupts hard disabled.
1336 */
1337EXC_COMMON_BEGIN(soft_nmi_common)
1338	mr	r10,r1
1339	ld	r1,PACAEMERGSP(r13)
1340	subi	r1,r1,INT_FRAME_SIZE
1341	EXCEPTION_COMMON_NORET_STACK(PACA_EXGEN, 0x900,
1342			system_reset, soft_nmi_interrupt,
1343			ADD_NVGPRS;ADD_RECONCILE)
1344	b	ret_from_except
1345
1346#else
1347#define MASKED_DEC_HANDLER_LABEL 2f /* normal return */
1348#define MASKED_DEC_HANDLER(_H)
1349#endif
1350
1351/*
1352 * An interrupt came in while soft-disabled. We set paca->irq_happened, then:
1353 * - If it was a decrementer interrupt, we bump the dec to max and and return.
1354 * - If it was a doorbell we return immediately since doorbells are edge
1355 *   triggered and won't automatically refire.
1356 * - If it was a HMI we return immediately since we handled it in realmode
1357 *   and it won't refire.
1358 * - else we hard disable and return.
1359 * This is called with r10 containing the value to OR to the paca field.
1360 */
1361#define MASKED_INTERRUPT(_H)				\
1362masked_##_H##interrupt:					\
1363	std	r11,PACA_EXGEN+EX_R11(r13);		\
1364	lbz	r11,PACAIRQHAPPENED(r13);		\
1365	or	r11,r11,r10;				\
1366	stb	r11,PACAIRQHAPPENED(r13);		\
1367	cmpwi	r10,PACA_IRQ_DEC;			\
1368	bne	1f;					\
1369	lis	r10,0x7fff;				\
1370	ori	r10,r10,0xffff;				\
1371	mtspr	SPRN_DEC,r10;				\
1372	b	MASKED_DEC_HANDLER_LABEL;		\
13731:	cmpwi	r10,PACA_IRQ_DBELL;			\
1374	beq	2f;					\
1375	cmpwi	r10,PACA_IRQ_HMI;			\
1376	beq	2f;					\
1377	mfspr	r10,SPRN_##_H##SRR1;			\
1378	rldicl	r10,r10,48,1; /* clear MSR_EE */	\
1379	rotldi	r10,r10,16;				\
1380	mtspr	SPRN_##_H##SRR1,r10;			\
13812:	mtcrf	0x80,r9;				\
1382	ld	r9,PACA_EXGEN+EX_R9(r13);		\
1383	ld	r10,PACA_EXGEN+EX_R10(r13);		\
1384	ld	r11,PACA_EXGEN+EX_R11(r13);		\
1385	GET_SCRATCH0(r13);				\
1386	##_H##rfid;					\
1387	b	.;					\
1388	MASKED_DEC_HANDLER(_H)
1389
1390/*
1391 * Real mode exceptions actually use this too, but alternate
1392 * instruction code patches (which end up in the common .text area)
1393 * cannot reach these if they are put there.
1394 */
1395USE_FIXED_SECTION(virt_trampolines)
1396	MASKED_INTERRUPT()
1397	MASKED_INTERRUPT(H)
1398
1399#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
1400TRAMP_REAL_BEGIN(kvmppc_skip_interrupt)
1401	/*
1402	 * Here all GPRs are unchanged from when the interrupt happened
1403	 * except for r13, which is saved in SPRG_SCRATCH0.
1404	 */
1405	mfspr	r13, SPRN_SRR0
1406	addi	r13, r13, 4
1407	mtspr	SPRN_SRR0, r13
1408	GET_SCRATCH0(r13)
1409	rfid
1410	b	.
1411
1412TRAMP_REAL_BEGIN(kvmppc_skip_Hinterrupt)
1413	/*
1414	 * Here all GPRs are unchanged from when the interrupt happened
1415	 * except for r13, which is saved in SPRG_SCRATCH0.
1416	 */
1417	mfspr	r13, SPRN_HSRR0
1418	addi	r13, r13, 4
1419	mtspr	SPRN_HSRR0, r13
1420	GET_SCRATCH0(r13)
1421	hrfid
1422	b	.
1423#endif
1424
1425/*
1426 * Ensure that any handlers that get invoked from the exception prologs
1427 * above are below the first 64KB (0x10000) of the kernel image because
1428 * the prologs assemble the addresses of these handlers using the
1429 * LOAD_HANDLER macro, which uses an ori instruction.
1430 */
1431
1432/*** Common interrupt handlers ***/
1433
1434
1435	/*
1436	 * Relocation-on interrupts: A subset of the interrupts can be delivered
1437	 * with IR=1/DR=1, if AIL==2 and MSR.HV won't be changed by delivering
1438	 * it.  Addresses are the same as the original interrupt addresses, but
1439	 * offset by 0xc000000000004000.
1440	 * It's impossible to receive interrupts below 0x300 via this mechanism.
1441	 * KVM: None of these traps are from the guest ; anything that escalated
1442	 * to HV=1 from HV=0 is delivered via real mode handlers.
1443	 */
1444
1445	/*
1446	 * This uses the standard macro, since the original 0x300 vector
1447	 * only has extra guff for STAB-based processors -- which never
1448	 * come here.
1449	 */
1450
1451EXC_COMMON_BEGIN(ppc64_runlatch_on_trampoline)
1452	b	__ppc64_runlatch_on
1453
1454USE_FIXED_SECTION(virt_trampolines)
1455	/*
1456	 * The __end_interrupts marker must be past the out-of-line (OOL)
1457	 * handlers, so that they are copied to real address 0x100 when running
1458	 * a relocatable kernel. This ensures they can be reached from the short
1459	 * trampoline handlers (like 0x4f00, 0x4f20, etc.) which branch
1460	 * directly, without using LOAD_HANDLER().
1461	 */
1462	.align	7
1463	.globl	__end_interrupts
1464__end_interrupts:
1465DEFINE_FIXED_SYMBOL(__end_interrupts)
1466
1467#ifdef CONFIG_PPC_970_NAP
1468EXC_COMMON_BEGIN(power4_fixup_nap)
1469	andc	r9,r9,r10
1470	std	r9,TI_LOCAL_FLAGS(r11)
1471	ld	r10,_LINK(r1)		/* make idle task do the */
1472	std	r10,_NIP(r1)		/* equivalent of a blr */
1473	blr
1474#endif
1475
1476CLOSE_FIXED_SECTION(real_vectors);
1477CLOSE_FIXED_SECTION(real_trampolines);
1478CLOSE_FIXED_SECTION(virt_vectors);
1479CLOSE_FIXED_SECTION(virt_trampolines);
1480
1481USE_TEXT_SECTION()
1482
1483/*
1484 * Hash table stuff
1485 */
1486	.balign	IFETCH_ALIGN_BYTES
1487do_hash_page:
1488#ifdef CONFIG_PPC_STD_MMU_64
1489	andis.	r0,r4,0xa450		/* weird error? */
1490	bne-	handle_page_fault	/* if not, try to insert a HPTE */
1491	CURRENT_THREAD_INFO(r11, r1)
1492	lwz	r0,TI_PREEMPT(r11)	/* If we're in an "NMI" */
1493	andis.	r0,r0,NMI_MASK@h	/* (i.e. an irq when soft-disabled) */
1494	bne	77f			/* then don't call hash_page now */
1495
1496	/*
1497	 * r3 contains the faulting address
1498	 * r4 msr
1499	 * r5 contains the trap number
1500	 * r6 contains dsisr
1501	 *
1502	 * at return r3 = 0 for success, 1 for page fault, negative for error
1503	 */
1504        mr 	r4,r12
1505	ld      r6,_DSISR(r1)
1506	bl	__hash_page		/* build HPTE if possible */
1507        cmpdi	r3,0			/* see if __hash_page succeeded */
1508
1509	/* Success */
1510	beq	fast_exc_return_irq	/* Return from exception on success */
1511
1512	/* Error */
1513	blt-	13f
1514
1515	/* Reload DSISR into r4 for the DABR check below */
1516	ld      r4,_DSISR(r1)
1517#endif /* CONFIG_PPC_STD_MMU_64 */
1518
1519/* Here we have a page fault that hash_page can't handle. */
1520handle_page_fault:
152111:	andis.  r0,r4,DSISR_DABRMATCH@h
1522	bne-    handle_dabr_fault
1523	ld	r4,_DAR(r1)
1524	ld	r5,_DSISR(r1)
1525	addi	r3,r1,STACK_FRAME_OVERHEAD
1526	bl	do_page_fault
1527	cmpdi	r3,0
1528	beq+	12f
1529	bl	save_nvgprs
1530	mr	r5,r3
1531	addi	r3,r1,STACK_FRAME_OVERHEAD
1532	lwz	r4,_DAR(r1)
1533	bl	bad_page_fault
1534	b	ret_from_except
1535
1536/* We have a data breakpoint exception - handle it */
1537handle_dabr_fault:
1538	bl	save_nvgprs
1539	ld      r4,_DAR(r1)
1540	ld      r5,_DSISR(r1)
1541	addi    r3,r1,STACK_FRAME_OVERHEAD
1542	bl      do_break
154312:	b       ret_from_except_lite
1544
1545
1546#ifdef CONFIG_PPC_STD_MMU_64
1547/* We have a page fault that hash_page could handle but HV refused
1548 * the PTE insertion
1549 */
155013:	bl	save_nvgprs
1551	mr	r5,r3
1552	addi	r3,r1,STACK_FRAME_OVERHEAD
1553	ld	r4,_DAR(r1)
1554	bl	low_hash_fault
1555	b	ret_from_except
1556#endif
1557
1558/*
1559 * We come here as a result of a DSI at a point where we don't want
1560 * to call hash_page, such as when we are accessing memory (possibly
1561 * user memory) inside a PMU interrupt that occurred while interrupts
1562 * were soft-disabled.  We want to invoke the exception handler for
1563 * the access, or panic if there isn't a handler.
1564 */
156577:	bl	save_nvgprs
1566	mr	r4,r3
1567	addi	r3,r1,STACK_FRAME_OVERHEAD
1568	li	r5,SIGSEGV
1569	bl	bad_page_fault
1570	b	ret_from_except
1571
1572/*
1573 * Here we have detected that the kernel stack pointer is bad.
1574 * R9 contains the saved CR, r13 points to the paca,
1575 * r10 contains the (bad) kernel stack pointer,
1576 * r11 and r12 contain the saved SRR0 and SRR1.
1577 * We switch to using an emergency stack, save the registers there,
1578 * and call kernel_bad_stack(), which panics.
1579 */
1580bad_stack:
1581	ld	r1,PACAEMERGSP(r13)
1582	subi	r1,r1,64+INT_FRAME_SIZE
1583	std	r9,_CCR(r1)
1584	std	r10,GPR1(r1)
1585	std	r11,_NIP(r1)
1586	std	r12,_MSR(r1)
1587	mfspr	r11,SPRN_DAR
1588	mfspr	r12,SPRN_DSISR
1589	std	r11,_DAR(r1)
1590	std	r12,_DSISR(r1)
1591	mflr	r10
1592	mfctr	r11
1593	mfxer	r12
1594	std	r10,_LINK(r1)
1595	std	r11,_CTR(r1)
1596	std	r12,_XER(r1)
1597	SAVE_GPR(0,r1)
1598	SAVE_GPR(2,r1)
1599	ld	r10,EX_R3(r3)
1600	std	r10,GPR3(r1)
1601	SAVE_GPR(4,r1)
1602	SAVE_4GPRS(5,r1)
1603	ld	r9,EX_R9(r3)
1604	ld	r10,EX_R10(r3)
1605	SAVE_2GPRS(9,r1)
1606	ld	r9,EX_R11(r3)
1607	ld	r10,EX_R12(r3)
1608	ld	r11,EX_R13(r3)
1609	std	r9,GPR11(r1)
1610	std	r10,GPR12(r1)
1611	std	r11,GPR13(r1)
1612BEGIN_FTR_SECTION
1613	ld	r10,EX_CFAR(r3)
1614	std	r10,ORIG_GPR3(r1)
1615END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
1616	SAVE_8GPRS(14,r1)
1617	SAVE_10GPRS(22,r1)
1618	lhz	r12,PACA_TRAP_SAVE(r13)
1619	std	r12,_TRAP(r1)
1620	addi	r11,r1,INT_FRAME_SIZE
1621	std	r11,0(r1)
1622	li	r12,0
1623	std	r12,0(r11)
1624	ld	r2,PACATOC(r13)
1625	ld	r11,exception_marker@toc(r2)
1626	std	r12,RESULT(r1)
1627	std	r11,STACK_FRAME_OVERHEAD-16(r1)
16281:	addi	r3,r1,STACK_FRAME_OVERHEAD
1629	bl	kernel_bad_stack
1630	b	1b
1631_ASM_NOKPROBE_SYMBOL(bad_stack);
1632
1633/*
1634 * When doorbell is triggered from system reset wakeup, the message is
1635 * not cleared, so it would fire again when EE is enabled.
1636 *
1637 * When coming from local_irq_enable, there may be the same problem if
1638 * we were hard disabled.
1639 *
1640 * Execute msgclr to clear pending exceptions before handling it.
1641 */
1642h_doorbell_common_msgclr:
1643	LOAD_REG_IMMEDIATE(r3, PPC_DBELL_MSGTYPE << (63-36))
1644	PPC_MSGCLR(3)
1645	b 	h_doorbell_common
1646
1647doorbell_super_common_msgclr:
1648	LOAD_REG_IMMEDIATE(r3, PPC_DBELL_MSGTYPE << (63-36))
1649	PPC_MSGCLRP(3)
1650	b 	doorbell_super_common
1651
1652/*
1653 * Called from arch_local_irq_enable when an interrupt needs
1654 * to be resent. r3 contains 0x500, 0x900, 0xa00 or 0xe80 to indicate
1655 * which kind of interrupt. MSR:EE is already off. We generate a
1656 * stackframe like if a real interrupt had happened.
1657 *
1658 * Note: While MSR:EE is off, we need to make sure that _MSR
1659 * in the generated frame has EE set to 1 or the exception
1660 * handler will not properly re-enable them.
1661 *
1662 * Note that we don't specify LR as the NIP (return address) for
1663 * the interrupt because that would unbalance the return branch
1664 * predictor.
1665 */
1666_GLOBAL(__replay_interrupt)
1667	/* We are going to jump to the exception common code which
1668	 * will retrieve various register values from the PACA which
1669	 * we don't give a damn about, so we don't bother storing them.
1670	 */
1671	mfmsr	r12
1672	LOAD_REG_ADDR(r11, 1f)
1673	mfcr	r9
1674	ori	r12,r12,MSR_EE
1675	cmpwi	r3,0x900
1676	beq	decrementer_common
1677	cmpwi	r3,0x500
1678	beq	hardware_interrupt_common
1679BEGIN_FTR_SECTION
1680	cmpwi	r3,0xe80
1681	beq	h_doorbell_common_msgclr
1682	cmpwi	r3,0xea0
1683	beq	h_virt_irq_common
1684	cmpwi	r3,0xe60
1685	beq	hmi_exception_common
1686FTR_SECTION_ELSE
1687	cmpwi	r3,0xa00
1688	beq	doorbell_super_common_msgclr
1689ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
16901:
1691	blr
1692
1693_ASM_NOKPROBE_SYMBOL(__replay_interrupt)
1694