xref: /openbmc/linux/arch/powerpc/kernel/exceptions-64s.S (revision b24413180f5600bcb3bb70fbed5cf186b60864bd)
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * This file contains the 64-bit "server" PowerPC variant
4 * of the low level exception handling including exception
5 * vectors, exception return, part of the slb and stab
6 * handling and other fixed offset specific things.
7 *
8 * This file is meant to be #included from head_64.S due to
9 * position dependent assembly.
10 *
11 * Most of this originates from head_64.S and thus has the same
12 * copyright history.
13 *
14 */
15
16#include <asm/hw_irq.h>
17#include <asm/exception-64s.h>
18#include <asm/ptrace.h>
19#include <asm/cpuidle.h>
20#include <asm/head-64.h>
21
22/*
23 * There are a few constraints to be concerned with.
24 * - Real mode exceptions code/data must be located at their physical location.
25 * - Virtual mode exceptions must be mapped at their 0xc000... location.
26 * - Fixed location code must not call directly beyond the __end_interrupts
27 *   area when built with CONFIG_RELOCATABLE. LOAD_HANDLER / bctr sequence
28 *   must be used.
29 * - LOAD_HANDLER targets must be within first 64K of physical 0 /
30 *   virtual 0xc00...
31 * - Conditional branch targets must be within +/-32K of caller.
32 *
33 * "Virtual exceptions" run with relocation on (MSR_IR=1, MSR_DR=1), and
34 * therefore don't have to run in physically located code or rfid to
35 * virtual mode kernel code. However on relocatable kernels they do have
36 * to branch to KERNELBASE offset because the rest of the kernel (outside
37 * the exception vectors) may be located elsewhere.
38 *
39 * Virtual exceptions correspond with physical, except their entry points
40 * are offset by 0xc000000000000000 and also tend to get an added 0x4000
41 * offset applied. Virtual exceptions are enabled with the Alternate
42 * Interrupt Location (AIL) bit set in the LPCR. However this does not
43 * guarantee they will be delivered virtually. Some conditions (see the ISA)
44 * cause exceptions to be delivered in real mode.
45 *
46 * It's impossible to receive interrupts below 0x300 via AIL.
47 *
48 * KVM: None of the virtual exceptions are from the guest. Anything that
49 * escalated to HV=1 from HV=0 is delivered via real mode handlers.
50 *
51 *
52 * We layout physical memory as follows:
53 * 0x0000 - 0x00ff : Secondary processor spin code
54 * 0x0100 - 0x18ff : Real mode pSeries interrupt vectors
55 * 0x1900 - 0x3fff : Real mode trampolines
56 * 0x4000 - 0x58ff : Relon (IR=1,DR=1) mode pSeries interrupt vectors
57 * 0x5900 - 0x6fff : Relon mode trampolines
58 * 0x7000 - 0x7fff : FWNMI data area
59 * 0x8000 -   .... : Common interrupt handlers, remaining early
60 *                   setup code, rest of kernel.
61 *
62 * We could reclaim 0x4000-0x42ff for real mode trampolines if the space
63 * is necessary. Until then it's more consistent to explicitly put VIRT_NONE
64 * vectors there.
65 */
66OPEN_FIXED_SECTION(real_vectors,        0x0100, 0x1900)
67OPEN_FIXED_SECTION(real_trampolines,    0x1900, 0x4000)
68OPEN_FIXED_SECTION(virt_vectors,        0x4000, 0x5900)
69OPEN_FIXED_SECTION(virt_trampolines,    0x5900, 0x7000)
70#if defined(CONFIG_PPC_PSERIES) || defined(CONFIG_PPC_POWERNV)
71/*
72 * Data area reserved for FWNMI option.
73 * This address (0x7000) is fixed by the RPA.
74 * pseries and powernv need to keep the whole page from
75 * 0x7000 to 0x8000 free for use by the firmware
76 */
77ZERO_FIXED_SECTION(fwnmi_page,          0x7000, 0x8000)
78OPEN_TEXT_SECTION(0x8000)
79#else
80OPEN_TEXT_SECTION(0x7000)
81#endif
82
83USE_FIXED_SECTION(real_vectors)
84
85/*
86 * This is the start of the interrupt handlers for pSeries
87 * This code runs with relocation off.
88 * Code from here to __end_interrupts gets copied down to real
89 * address 0x100 when we are running a relocatable kernel.
90 * Therefore any relative branches in this section must only
91 * branch to labels in this section.
92 */
93	.globl __start_interrupts
94__start_interrupts:
95
96/* No virt vectors corresponding with 0x0..0x100 */
97EXC_VIRT_NONE(0x4000, 0x100)
98
99
100#ifdef CONFIG_PPC_P7_NAP
101	/*
102	 * If running native on arch 2.06 or later, check if we are waking up
103	 * from nap/sleep/winkle, and branch to idle handler. This tests SRR1
104	 * bits 46:47. A non-0 value indicates that we are coming from a power
105	 * saving state. The idle wakeup handler initially runs in real mode,
106	 * but we branch to the 0xc000... address so we can turn on relocation
107	 * with mtmsr.
108	 */
109#define IDLETEST(n)							\
110	BEGIN_FTR_SECTION ;						\
111	mfspr	r10,SPRN_SRR1 ;						\
112	rlwinm.	r10,r10,47-31,30,31 ;					\
113	beq-	1f ;							\
114	cmpwi	cr3,r10,2 ;						\
115	BRANCH_TO_C000(r10, system_reset_idle_common) ;			\
1161:									\
117	END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
118#else
119#define IDLETEST NOTEST
120#endif
121
122EXC_REAL_BEGIN(system_reset, 0x100, 0x100)
123	SET_SCRATCH0(r13)
124	/*
125	 * MSR_RI is not enabled, because PACA_EXNMI and nmi stack is
126	 * being used, so a nested NMI exception would corrupt it.
127	 */
128	EXCEPTION_PROLOG_PSERIES_NORI(PACA_EXNMI, system_reset_common, EXC_STD,
129				 IDLETEST, 0x100)
130
131EXC_REAL_END(system_reset, 0x100, 0x100)
132EXC_VIRT_NONE(0x4100, 0x100)
133
134#ifdef CONFIG_PPC_P7_NAP
135EXC_COMMON_BEGIN(system_reset_idle_common)
136	mfspr	r12,SPRN_SRR1
137	b	pnv_powersave_wakeup
138#endif
139
140EXC_COMMON_BEGIN(system_reset_common)
141	/*
142	 * Increment paca->in_nmi then enable MSR_RI. SLB or MCE will be able
143	 * to recover, but nested NMI will notice in_nmi and not recover
144	 * because of the use of the NMI stack. in_nmi reentrancy is tested in
145	 * system_reset_exception.
146	 */
147	lhz	r10,PACA_IN_NMI(r13)
148	addi	r10,r10,1
149	sth	r10,PACA_IN_NMI(r13)
150	li	r10,MSR_RI
151	mtmsrd 	r10,1
152
153	mr	r10,r1
154	ld	r1,PACA_NMI_EMERG_SP(r13)
155	subi	r1,r1,INT_FRAME_SIZE
156	EXCEPTION_COMMON_NORET_STACK(PACA_EXNMI, 0x100,
157			system_reset, system_reset_exception,
158			ADD_NVGPRS;ADD_RECONCILE)
159
160	/*
161	 * The stack is no longer in use, decrement in_nmi.
162	 */
163	lhz	r10,PACA_IN_NMI(r13)
164	subi	r10,r10,1
165	sth	r10,PACA_IN_NMI(r13)
166
167	b	ret_from_except
168
169#ifdef CONFIG_PPC_PSERIES
170/*
171 * Vectors for the FWNMI option.  Share common code.
172 */
173TRAMP_REAL_BEGIN(system_reset_fwnmi)
174	SET_SCRATCH0(r13)		/* save r13 */
175	/* See comment at system_reset exception */
176	EXCEPTION_PROLOG_PSERIES_NORI(PACA_EXNMI, system_reset_common,
177						EXC_STD, NOTEST, 0x100)
178#endif /* CONFIG_PPC_PSERIES */
179
180
181EXC_REAL_BEGIN(machine_check, 0x200, 0x100)
182	/* This is moved out of line as it can be patched by FW, but
183	 * some code path might still want to branch into the original
184	 * vector
185	 */
186	SET_SCRATCH0(r13)		/* save r13 */
187	EXCEPTION_PROLOG_0(PACA_EXMC)
188BEGIN_FTR_SECTION
189	b	machine_check_powernv_early
190FTR_SECTION_ELSE
191	b	machine_check_pSeries_0
192ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
193EXC_REAL_END(machine_check, 0x200, 0x100)
194EXC_VIRT_NONE(0x4200, 0x100)
195TRAMP_REAL_BEGIN(machine_check_powernv_early)
196BEGIN_FTR_SECTION
197	EXCEPTION_PROLOG_1(PACA_EXMC, NOTEST, 0x200)
198	/*
199	 * Register contents:
200	 * R13		= PACA
201	 * R9		= CR
202	 * Original R9 to R13 is saved on PACA_EXMC
203	 *
204	 * Switch to mc_emergency stack and handle re-entrancy (we limit
205	 * the nested MCE upto level 4 to avoid stack overflow).
206	 * Save MCE registers srr1, srr0, dar and dsisr and then set ME=1
207	 *
208	 * We use paca->in_mce to check whether this is the first entry or
209	 * nested machine check. We increment paca->in_mce to track nested
210	 * machine checks.
211	 *
212	 * If this is the first entry then set stack pointer to
213	 * paca->mc_emergency_sp, otherwise r1 is already pointing to
214	 * stack frame on mc_emergency stack.
215	 *
216	 * NOTE: We are here with MSR_ME=0 (off), which means we risk a
217	 * checkstop if we get another machine check exception before we do
218	 * rfid with MSR_ME=1.
219	 *
220	 * This interrupt can wake directly from idle. If that is the case,
221	 * the machine check is handled then the idle wakeup code is called
222	 * to restore state. In that case, the POWER9 DD1 idle PACA workaround
223	 * is not applied in the early machine check code, which will cause
224	 * bugs.
225	 */
226	mr	r11,r1			/* Save r1 */
227	lhz	r10,PACA_IN_MCE(r13)
228	cmpwi	r10,0			/* Are we in nested machine check */
229	bne	0f			/* Yes, we are. */
230	/* First machine check entry */
231	ld	r1,PACAMCEMERGSP(r13)	/* Use MC emergency stack */
2320:	subi	r1,r1,INT_FRAME_SIZE	/* alloc stack frame */
233	addi	r10,r10,1		/* increment paca->in_mce */
234	sth	r10,PACA_IN_MCE(r13)
235	/* Limit nested MCE to level 4 to avoid stack overflow */
236	cmpwi	r10,4
237	bgt	2f			/* Check if we hit limit of 4 */
238	std	r11,GPR1(r1)		/* Save r1 on the stack. */
239	std	r11,0(r1)		/* make stack chain pointer */
240	mfspr	r11,SPRN_SRR0		/* Save SRR0 */
241	std	r11,_NIP(r1)
242	mfspr	r11,SPRN_SRR1		/* Save SRR1 */
243	std	r11,_MSR(r1)
244	mfspr	r11,SPRN_DAR		/* Save DAR */
245	std	r11,_DAR(r1)
246	mfspr	r11,SPRN_DSISR		/* Save DSISR */
247	std	r11,_DSISR(r1)
248	std	r9,_CCR(r1)		/* Save CR in stackframe */
249	/* Save r9 through r13 from EXMC save area to stack frame. */
250	EXCEPTION_PROLOG_COMMON_2(PACA_EXMC)
251	mfmsr	r11			/* get MSR value */
252	ori	r11,r11,MSR_ME		/* turn on ME bit */
253	ori	r11,r11,MSR_RI		/* turn on RI bit */
254	LOAD_HANDLER(r12, machine_check_handle_early)
2551:	mtspr	SPRN_SRR0,r12
256	mtspr	SPRN_SRR1,r11
257	rfid
258	b	.	/* prevent speculative execution */
2592:
260	/* Stack overflow. Stay on emergency stack and panic.
261	 * Keep the ME bit off while panic-ing, so that if we hit
262	 * another machine check we checkstop.
263	 */
264	addi	r1,r1,INT_FRAME_SIZE	/* go back to previous stack frame */
265	ld	r11,PACAKMSR(r13)
266	LOAD_HANDLER(r12, unrecover_mce)
267	li	r10,MSR_ME
268	andc	r11,r11,r10		/* Turn off MSR_ME */
269	b	1b
270	b	.	/* prevent speculative execution */
271END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
272
273TRAMP_REAL_BEGIN(machine_check_pSeries)
274	.globl machine_check_fwnmi
275machine_check_fwnmi:
276	SET_SCRATCH0(r13)		/* save r13 */
277	EXCEPTION_PROLOG_0(PACA_EXMC)
278machine_check_pSeries_0:
279	EXCEPTION_PROLOG_1(PACA_EXMC, KVMTEST_PR, 0x200)
280	/*
281	 * MSR_RI is not enabled, because PACA_EXMC is being used, so a
282	 * nested machine check corrupts it. machine_check_common enables
283	 * MSR_RI.
284	 */
285	EXCEPTION_PROLOG_PSERIES_1_NORI(machine_check_common, EXC_STD)
286
287TRAMP_KVM_SKIP(PACA_EXMC, 0x200)
288
289EXC_COMMON_BEGIN(machine_check_common)
290	/*
291	 * Machine check is different because we use a different
292	 * save area: PACA_EXMC instead of PACA_EXGEN.
293	 */
294	mfspr	r10,SPRN_DAR
295	std	r10,PACA_EXMC+EX_DAR(r13)
296	mfspr	r10,SPRN_DSISR
297	stw	r10,PACA_EXMC+EX_DSISR(r13)
298	EXCEPTION_PROLOG_COMMON(0x200, PACA_EXMC)
299	FINISH_NAP
300	RECONCILE_IRQ_STATE(r10, r11)
301	ld	r3,PACA_EXMC+EX_DAR(r13)
302	lwz	r4,PACA_EXMC+EX_DSISR(r13)
303	/* Enable MSR_RI when finished with PACA_EXMC */
304	li	r10,MSR_RI
305	mtmsrd 	r10,1
306	std	r3,_DAR(r1)
307	std	r4,_DSISR(r1)
308	bl	save_nvgprs
309	addi	r3,r1,STACK_FRAME_OVERHEAD
310	bl	machine_check_exception
311	b	ret_from_except
312
313#define MACHINE_CHECK_HANDLER_WINDUP			\
314	/* Clear MSR_RI before setting SRR0 and SRR1. */\
315	li	r0,MSR_RI;				\
316	mfmsr	r9;		/* get MSR value */	\
317	andc	r9,r9,r0;				\
318	mtmsrd	r9,1;		/* Clear MSR_RI */	\
319	/* Move original SRR0 and SRR1 into the respective regs */	\
320	ld	r9,_MSR(r1);				\
321	mtspr	SPRN_SRR1,r9;				\
322	ld	r3,_NIP(r1);				\
323	mtspr	SPRN_SRR0,r3;				\
324	ld	r9,_CTR(r1);				\
325	mtctr	r9;					\
326	ld	r9,_XER(r1);				\
327	mtxer	r9;					\
328	ld	r9,_LINK(r1);				\
329	mtlr	r9;					\
330	REST_GPR(0, r1);				\
331	REST_8GPRS(2, r1);				\
332	REST_GPR(10, r1);				\
333	ld	r11,_CCR(r1);				\
334	mtcr	r11;					\
335	/* Decrement paca->in_mce. */			\
336	lhz	r12,PACA_IN_MCE(r13);			\
337	subi	r12,r12,1;				\
338	sth	r12,PACA_IN_MCE(r13);			\
339	REST_GPR(11, r1);				\
340	REST_2GPRS(12, r1);				\
341	/* restore original r1. */			\
342	ld	r1,GPR1(r1)
343
344#ifdef CONFIG_PPC_P7_NAP
345/*
346 * This is an idle wakeup. Low level machine check has already been
347 * done. Queue the event then call the idle code to do the wake up.
348 */
349EXC_COMMON_BEGIN(machine_check_idle_common)
350	bl	machine_check_queue_event
351
352	/*
353	 * We have not used any non-volatile GPRs here, and as a rule
354	 * most exception code including machine check does not.
355	 * Therefore PACA_NAPSTATELOST does not need to be set. Idle
356	 * wakeup will restore volatile registers.
357	 *
358	 * Load the original SRR1 into r3 for pnv_powersave_wakeup_mce.
359	 *
360	 * Then decrement MCE nesting after finishing with the stack.
361	 */
362	ld	r3,_MSR(r1)
363
364	lhz	r11,PACA_IN_MCE(r13)
365	subi	r11,r11,1
366	sth	r11,PACA_IN_MCE(r13)
367
368	/* Turn off the RI bit because SRR1 is used by idle wakeup code. */
369	/* Recoverability could be improved by reducing the use of SRR1. */
370	li	r11,0
371	mtmsrd	r11,1
372
373	b	pnv_powersave_wakeup_mce
374#endif
375	/*
376	 * Handle machine check early in real mode. We come here with
377	 * ME=1, MMU (IR=0 and DR=0) off and using MC emergency stack.
378	 */
379EXC_COMMON_BEGIN(machine_check_handle_early)
380	std	r0,GPR0(r1)	/* Save r0 */
381	EXCEPTION_PROLOG_COMMON_3(0x200)
382	bl	save_nvgprs
383	addi	r3,r1,STACK_FRAME_OVERHEAD
384	bl	machine_check_early
385	std	r3,RESULT(r1)	/* Save result */
386	ld	r12,_MSR(r1)
387
388#ifdef	CONFIG_PPC_P7_NAP
389	/*
390	 * Check if thread was in power saving mode. We come here when any
391	 * of the following is true:
392	 * a. thread wasn't in power saving mode
393	 * b. thread was in power saving mode with no state loss,
394	 *    supervisor state loss or hypervisor state loss.
395	 *
396	 * Go back to nap/sleep/winkle mode again if (b) is true.
397	 */
398	BEGIN_FTR_SECTION
399	rlwinm.	r11,r12,47-31,30,31
400	bne	machine_check_idle_common
401	END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
402#endif
403
404	/*
405	 * Check if we are coming from hypervisor userspace. If yes then we
406	 * continue in host kernel in V mode to deliver the MC event.
407	 */
408	rldicl.	r11,r12,4,63		/* See if MC hit while in HV mode. */
409	beq	5f
410	andi.	r11,r12,MSR_PR		/* See if coming from user. */
411	bne	9f			/* continue in V mode if we are. */
412
4135:
414#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
415	/*
416	 * We are coming from kernel context. Check if we are coming from
417	 * guest. if yes, then we can continue. We will fall through
418	 * do_kvm_200->kvmppc_interrupt to deliver the MC event to guest.
419	 */
420	lbz	r11,HSTATE_IN_GUEST(r13)
421	cmpwi	r11,0			/* Check if coming from guest */
422	bne	9f			/* continue if we are. */
423#endif
424	/*
425	 * At this point we are not sure about what context we come from.
426	 * Queue up the MCE event and return from the interrupt.
427	 * But before that, check if this is an un-recoverable exception.
428	 * If yes, then stay on emergency stack and panic.
429	 */
430	andi.	r11,r12,MSR_RI
431	bne	2f
4321:	mfspr	r11,SPRN_SRR0
433	LOAD_HANDLER(r10,unrecover_mce)
434	mtspr	SPRN_SRR0,r10
435	ld	r10,PACAKMSR(r13)
436	/*
437	 * We are going down. But there are chances that we might get hit by
438	 * another MCE during panic path and we may run into unstable state
439	 * with no way out. Hence, turn ME bit off while going down, so that
440	 * when another MCE is hit during panic path, system will checkstop
441	 * and hypervisor will get restarted cleanly by SP.
442	 */
443	li	r3,MSR_ME
444	andc	r10,r10,r3		/* Turn off MSR_ME */
445	mtspr	SPRN_SRR1,r10
446	rfid
447	b	.
4482:
449	/*
450	 * Check if we have successfully handled/recovered from error, if not
451	 * then stay on emergency stack and panic.
452	 */
453	ld	r3,RESULT(r1)	/* Load result */
454	cmpdi	r3,0		/* see if we handled MCE successfully */
455
456	beq	1b		/* if !handled then panic */
457	/*
458	 * Return from MC interrupt.
459	 * Queue up the MCE event so that we can log it later, while
460	 * returning from kernel or opal call.
461	 */
462	bl	machine_check_queue_event
463	MACHINE_CHECK_HANDLER_WINDUP
464	rfid
4659:
466	/* Deliver the machine check to host kernel in V mode. */
467	MACHINE_CHECK_HANDLER_WINDUP
468	b	machine_check_pSeries
469
470EXC_COMMON_BEGIN(unrecover_mce)
471	/* Invoke machine_check_exception to print MCE event and panic. */
472	addi	r3,r1,STACK_FRAME_OVERHEAD
473	bl	machine_check_exception
474	/*
475	 * We will not reach here. Even if we did, there is no way out. Call
476	 * unrecoverable_exception and die.
477	 */
4781:	addi	r3,r1,STACK_FRAME_OVERHEAD
479	bl	unrecoverable_exception
480	b	1b
481
482
483EXC_REAL(data_access, 0x300, 0x80)
484EXC_VIRT(data_access, 0x4300, 0x80, 0x300)
485TRAMP_KVM_SKIP(PACA_EXGEN, 0x300)
486
487EXC_COMMON_BEGIN(data_access_common)
488	/*
489	 * Here r13 points to the paca, r9 contains the saved CR,
490	 * SRR0 and SRR1 are saved in r11 and r12,
491	 * r9 - r13 are saved in paca->exgen.
492	 */
493	mfspr	r10,SPRN_DAR
494	std	r10,PACA_EXGEN+EX_DAR(r13)
495	mfspr	r10,SPRN_DSISR
496	stw	r10,PACA_EXGEN+EX_DSISR(r13)
497	EXCEPTION_PROLOG_COMMON(0x300, PACA_EXGEN)
498	RECONCILE_IRQ_STATE(r10, r11)
499	ld	r12,_MSR(r1)
500	ld	r3,PACA_EXGEN+EX_DAR(r13)
501	lwz	r4,PACA_EXGEN+EX_DSISR(r13)
502	li	r5,0x300
503	std	r3,_DAR(r1)
504	std	r4,_DSISR(r1)
505BEGIN_MMU_FTR_SECTION
506	b	do_hash_page		/* Try to handle as hpte fault */
507MMU_FTR_SECTION_ELSE
508	b	handle_page_fault
509ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)
510
511
512EXC_REAL_BEGIN(data_access_slb, 0x380, 0x80)
513	SET_SCRATCH0(r13)
514	EXCEPTION_PROLOG_0(PACA_EXSLB)
515	EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST_PR, 0x380)
516	mr	r12,r3	/* save r3 */
517	mfspr	r3,SPRN_DAR
518	mfspr	r11,SPRN_SRR1
519	crset	4*cr6+eq
520	BRANCH_TO_COMMON(r10, slb_miss_common)
521EXC_REAL_END(data_access_slb, 0x380, 0x80)
522
523EXC_VIRT_BEGIN(data_access_slb, 0x4380, 0x80)
524	SET_SCRATCH0(r13)
525	EXCEPTION_PROLOG_0(PACA_EXSLB)
526	EXCEPTION_PROLOG_1(PACA_EXSLB, NOTEST, 0x380)
527	mr	r12,r3	/* save r3 */
528	mfspr	r3,SPRN_DAR
529	mfspr	r11,SPRN_SRR1
530	crset	4*cr6+eq
531	BRANCH_TO_COMMON(r10, slb_miss_common)
532EXC_VIRT_END(data_access_slb, 0x4380, 0x80)
533TRAMP_KVM_SKIP(PACA_EXSLB, 0x380)
534
535
536EXC_REAL(instruction_access, 0x400, 0x80)
537EXC_VIRT(instruction_access, 0x4400, 0x80, 0x400)
538TRAMP_KVM(PACA_EXGEN, 0x400)
539
540EXC_COMMON_BEGIN(instruction_access_common)
541	EXCEPTION_PROLOG_COMMON(0x400, PACA_EXGEN)
542	RECONCILE_IRQ_STATE(r10, r11)
543	ld	r12,_MSR(r1)
544	ld	r3,_NIP(r1)
545	andis.	r4,r12,DSISR_BAD_FAULT_64S@h
546	li	r5,0x400
547	std	r3,_DAR(r1)
548	std	r4,_DSISR(r1)
549BEGIN_MMU_FTR_SECTION
550	b	do_hash_page		/* Try to handle as hpte fault */
551MMU_FTR_SECTION_ELSE
552	b	handle_page_fault
553ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)
554
555
556EXC_REAL_BEGIN(instruction_access_slb, 0x480, 0x80)
557	SET_SCRATCH0(r13)
558	EXCEPTION_PROLOG_0(PACA_EXSLB)
559	EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST_PR, 0x480)
560	mr	r12,r3	/* save r3 */
561	mfspr	r3,SPRN_SRR0		/* SRR0 is faulting address */
562	mfspr	r11,SPRN_SRR1
563	crclr	4*cr6+eq
564	BRANCH_TO_COMMON(r10, slb_miss_common)
565EXC_REAL_END(instruction_access_slb, 0x480, 0x80)
566
567EXC_VIRT_BEGIN(instruction_access_slb, 0x4480, 0x80)
568	SET_SCRATCH0(r13)
569	EXCEPTION_PROLOG_0(PACA_EXSLB)
570	EXCEPTION_PROLOG_1(PACA_EXSLB, NOTEST, 0x480)
571	mr	r12,r3	/* save r3 */
572	mfspr	r3,SPRN_SRR0		/* SRR0 is faulting address */
573	mfspr	r11,SPRN_SRR1
574	crclr	4*cr6+eq
575	BRANCH_TO_COMMON(r10, slb_miss_common)
576EXC_VIRT_END(instruction_access_slb, 0x4480, 0x80)
577TRAMP_KVM(PACA_EXSLB, 0x480)
578
579
580/*
581 * This handler is used by the 0x380 and 0x480 SLB miss interrupts, as well as
582 * the virtual mode 0x4380 and 0x4480 interrupts if AIL is enabled.
583 */
584EXC_COMMON_BEGIN(slb_miss_common)
585	/*
586	 * r13 points to the PACA, r9 contains the saved CR,
587	 * r12 contains the saved r3,
588	 * r11 contain the saved SRR1, SRR0 is still ready for return
589	 * r3 has the faulting address
590	 * r9 - r13 are saved in paca->exslb.
591 	 * cr6.eq is set for a D-SLB miss, clear for a I-SLB miss
592	 * We assume we aren't going to take any exceptions during this
593	 * procedure.
594	 */
595	mflr	r10
596	stw	r9,PACA_EXSLB+EX_CCR(r13)	/* save CR in exc. frame */
597	std	r10,PACA_EXSLB+EX_LR(r13)	/* save LR */
598
599	/*
600	 * Test MSR_RI before calling slb_allocate_realmode, because the
601	 * MSR in r11 gets clobbered. However we still want to allocate
602	 * SLB in case MSR_RI=0, to minimise the risk of getting stuck in
603	 * recursive SLB faults. So use cr5 for this, which is preserved.
604	 */
605	andi.	r11,r11,MSR_RI	/* check for unrecoverable exception */
606	cmpdi	cr5,r11,MSR_RI
607
608	crset	4*cr0+eq
609#ifdef CONFIG_PPC_STD_MMU_64
610BEGIN_MMU_FTR_SECTION
611	bl	slb_allocate
612END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX)
613#endif
614
615	ld	r10,PACA_EXSLB+EX_LR(r13)
616	lwz	r9,PACA_EXSLB+EX_CCR(r13)	/* get saved CR */
617	mtlr	r10
618
619	beq-	8f		/* if bad address, make full stack frame */
620
621	bne-	cr5,2f		/* if unrecoverable exception, oops */
622
623	/* All done -- return from exception. */
624
625.machine	push
626.machine	"power4"
627	mtcrf	0x80,r9
628	mtcrf	0x04,r9		/* MSR[RI] indication is in cr5 */
629	mtcrf	0x02,r9		/* I/D indication is in cr6 */
630	mtcrf	0x01,r9		/* slb_allocate uses cr0 and cr7 */
631.machine	pop
632
633	RESTORE_CTR(r9, PACA_EXSLB)
634	RESTORE_PPR_PACA(PACA_EXSLB, r9)
635	mr	r3,r12
636	ld	r9,PACA_EXSLB+EX_R9(r13)
637	ld	r10,PACA_EXSLB+EX_R10(r13)
638	ld	r11,PACA_EXSLB+EX_R11(r13)
639	ld	r12,PACA_EXSLB+EX_R12(r13)
640	ld	r13,PACA_EXSLB+EX_R13(r13)
641	rfid
642	b	.	/* prevent speculative execution */
643
6442:	std     r3,PACA_EXSLB+EX_DAR(r13)
645	mr	r3,r12
646	mfspr	r11,SPRN_SRR0
647	mfspr	r12,SPRN_SRR1
648	LOAD_HANDLER(r10,unrecov_slb)
649	mtspr	SPRN_SRR0,r10
650	ld	r10,PACAKMSR(r13)
651	mtspr	SPRN_SRR1,r10
652	rfid
653	b	.
654
6558:	std     r3,PACA_EXSLB+EX_DAR(r13)
656	mr	r3,r12
657	mfspr	r11,SPRN_SRR0
658	mfspr	r12,SPRN_SRR1
659	LOAD_HANDLER(r10,bad_addr_slb)
660	mtspr	SPRN_SRR0,r10
661	ld	r10,PACAKMSR(r13)
662	mtspr	SPRN_SRR1,r10
663	rfid
664	b	.
665
666EXC_COMMON_BEGIN(unrecov_slb)
667	EXCEPTION_PROLOG_COMMON(0x4100, PACA_EXSLB)
668	RECONCILE_IRQ_STATE(r10, r11)
669	bl	save_nvgprs
6701:	addi	r3,r1,STACK_FRAME_OVERHEAD
671	bl	unrecoverable_exception
672	b	1b
673
674EXC_COMMON_BEGIN(bad_addr_slb)
675	EXCEPTION_PROLOG_COMMON(0x380, PACA_EXSLB)
676	RECONCILE_IRQ_STATE(r10, r11)
677	ld	r3, PACA_EXSLB+EX_DAR(r13)
678	std	r3, _DAR(r1)
679	beq	cr6, 2f
680	li	r10, 0x480		/* fix trap number for I-SLB miss */
681	std	r10, _TRAP(r1)
6822:	bl	save_nvgprs
683	addi	r3, r1, STACK_FRAME_OVERHEAD
684	bl	slb_miss_bad_addr
685	b	ret_from_except
686
687EXC_REAL_BEGIN(hardware_interrupt, 0x500, 0x100)
688	.globl hardware_interrupt_hv;
689hardware_interrupt_hv:
690	BEGIN_FTR_SECTION
691		_MASKABLE_EXCEPTION_PSERIES(0x500, hardware_interrupt_common,
692					    EXC_HV, SOFTEN_TEST_HV)
693	FTR_SECTION_ELSE
694		_MASKABLE_EXCEPTION_PSERIES(0x500, hardware_interrupt_common,
695					    EXC_STD, SOFTEN_TEST_PR)
696	ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
697EXC_REAL_END(hardware_interrupt, 0x500, 0x100)
698
699EXC_VIRT_BEGIN(hardware_interrupt, 0x4500, 0x100)
700	.globl hardware_interrupt_relon_hv;
701hardware_interrupt_relon_hv:
702	BEGIN_FTR_SECTION
703		_MASKABLE_RELON_EXCEPTION_PSERIES(0x500, hardware_interrupt_common, EXC_HV, SOFTEN_TEST_HV)
704	FTR_SECTION_ELSE
705		_MASKABLE_RELON_EXCEPTION_PSERIES(0x500, hardware_interrupt_common, EXC_STD, SOFTEN_TEST_PR)
706	ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
707EXC_VIRT_END(hardware_interrupt, 0x4500, 0x100)
708
709TRAMP_KVM(PACA_EXGEN, 0x500)
710TRAMP_KVM_HV(PACA_EXGEN, 0x500)
711EXC_COMMON_ASYNC(hardware_interrupt_common, 0x500, do_IRQ)
712
713
714EXC_REAL(alignment, 0x600, 0x100)
715EXC_VIRT(alignment, 0x4600, 0x100, 0x600)
716TRAMP_KVM(PACA_EXGEN, 0x600)
717EXC_COMMON_BEGIN(alignment_common)
718	mfspr	r10,SPRN_DAR
719	std	r10,PACA_EXGEN+EX_DAR(r13)
720	mfspr	r10,SPRN_DSISR
721	stw	r10,PACA_EXGEN+EX_DSISR(r13)
722	EXCEPTION_PROLOG_COMMON(0x600, PACA_EXGEN)
723	ld	r3,PACA_EXGEN+EX_DAR(r13)
724	lwz	r4,PACA_EXGEN+EX_DSISR(r13)
725	std	r3,_DAR(r1)
726	std	r4,_DSISR(r1)
727	bl	save_nvgprs
728	RECONCILE_IRQ_STATE(r10, r11)
729	addi	r3,r1,STACK_FRAME_OVERHEAD
730	bl	alignment_exception
731	b	ret_from_except
732
733
734EXC_REAL(program_check, 0x700, 0x100)
735EXC_VIRT(program_check, 0x4700, 0x100, 0x700)
736TRAMP_KVM(PACA_EXGEN, 0x700)
737EXC_COMMON_BEGIN(program_check_common)
738	/*
739	 * It's possible to receive a TM Bad Thing type program check with
740	 * userspace register values (in particular r1), but with SRR1 reporting
741	 * that we came from the kernel. Normally that would confuse the bad
742	 * stack logic, and we would report a bad kernel stack pointer. Instead
743	 * we switch to the emergency stack if we're taking a TM Bad Thing from
744	 * the kernel.
745	 */
746	li	r10,MSR_PR		/* Build a mask of MSR_PR ..	*/
747	oris	r10,r10,0x200000@h	/* .. and SRR1_PROGTM		*/
748	and	r10,r10,r12		/* Mask SRR1 with that.		*/
749	srdi	r10,r10,8		/* Shift it so we can compare	*/
750	cmpldi	r10,(0x200000 >> 8)	/* .. with an immediate.	*/
751	bne 1f				/* If != go to normal path.	*/
752
753	/* SRR1 had PR=0 and SRR1_PROGTM=1, so use the emergency stack	*/
754	andi.	r10,r12,MSR_PR;		/* Set CR0 correctly for label	*/
755					/* 3 in EXCEPTION_PROLOG_COMMON	*/
756	mr	r10,r1			/* Save r1			*/
757	ld	r1,PACAEMERGSP(r13)	/* Use emergency stack		*/
758	subi	r1,r1,INT_FRAME_SIZE	/* alloc stack frame		*/
759	b 3f				/* Jump into the macro !!	*/
7601:	EXCEPTION_PROLOG_COMMON(0x700, PACA_EXGEN)
761	bl	save_nvgprs
762	RECONCILE_IRQ_STATE(r10, r11)
763	addi	r3,r1,STACK_FRAME_OVERHEAD
764	bl	program_check_exception
765	b	ret_from_except
766
767
768EXC_REAL(fp_unavailable, 0x800, 0x100)
769EXC_VIRT(fp_unavailable, 0x4800, 0x100, 0x800)
770TRAMP_KVM(PACA_EXGEN, 0x800)
771EXC_COMMON_BEGIN(fp_unavailable_common)
772	EXCEPTION_PROLOG_COMMON(0x800, PACA_EXGEN)
773	bne	1f			/* if from user, just load it up */
774	bl	save_nvgprs
775	RECONCILE_IRQ_STATE(r10, r11)
776	addi	r3,r1,STACK_FRAME_OVERHEAD
777	bl	kernel_fp_unavailable_exception
778	BUG_OPCODE
7791:
780#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
781BEGIN_FTR_SECTION
782	/* Test if 2 TM state bits are zero.  If non-zero (ie. userspace was in
783	 * transaction), go do TM stuff
784	 */
785	rldicl.	r0, r12, (64-MSR_TS_LG), (64-2)
786	bne-	2f
787END_FTR_SECTION_IFSET(CPU_FTR_TM)
788#endif
789	bl	load_up_fpu
790	b	fast_exception_return
791#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
7922:	/* User process was in a transaction */
793	bl	save_nvgprs
794	RECONCILE_IRQ_STATE(r10, r11)
795	addi	r3,r1,STACK_FRAME_OVERHEAD
796	bl	fp_unavailable_tm
797	b	ret_from_except
798#endif
799
800
801EXC_REAL_MASKABLE(decrementer, 0x900, 0x80)
802EXC_VIRT_MASKABLE(decrementer, 0x4900, 0x80, 0x900)
803TRAMP_KVM(PACA_EXGEN, 0x900)
804EXC_COMMON_ASYNC(decrementer_common, 0x900, timer_interrupt)
805
806
807EXC_REAL_HV(hdecrementer, 0x980, 0x80)
808EXC_VIRT_HV(hdecrementer, 0x4980, 0x80, 0x980)
809TRAMP_KVM_HV(PACA_EXGEN, 0x980)
810EXC_COMMON(hdecrementer_common, 0x980, hdec_interrupt)
811
812
813EXC_REAL_MASKABLE(doorbell_super, 0xa00, 0x100)
814EXC_VIRT_MASKABLE(doorbell_super, 0x4a00, 0x100, 0xa00)
815TRAMP_KVM(PACA_EXGEN, 0xa00)
816#ifdef CONFIG_PPC_DOORBELL
817EXC_COMMON_ASYNC(doorbell_super_common, 0xa00, doorbell_exception)
818#else
819EXC_COMMON_ASYNC(doorbell_super_common, 0xa00, unknown_exception)
820#endif
821
822
823EXC_REAL(trap_0b, 0xb00, 0x100)
824EXC_VIRT(trap_0b, 0x4b00, 0x100, 0xb00)
825TRAMP_KVM(PACA_EXGEN, 0xb00)
826EXC_COMMON(trap_0b_common, 0xb00, unknown_exception)
827
828/*
829 * system call / hypercall (0xc00, 0x4c00)
830 *
831 * The system call exception is invoked with "sc 0" and does not alter HV bit.
832 * There is support for kernel code to invoke system calls but there are no
833 * in-tree users.
834 *
835 * The hypercall is invoked with "sc 1" and sets HV=1.
836 *
837 * In HPT, sc 1 always goes to 0xc00 real mode. In RADIX, sc 1 can go to
838 * 0x4c00 virtual mode.
839 *
840 * Call convention:
841 *
842 * syscall register convention is in Documentation/powerpc/syscall64-abi.txt
843 *
844 * For hypercalls, the register convention is as follows:
845 * r0 volatile
846 * r1-2 nonvolatile
847 * r3 volatile parameter and return value for status
848 * r4-r10 volatile input and output value
849 * r11 volatile hypercall number and output value
850 * r12 volatile input and output value
851 * r13-r31 nonvolatile
852 * LR nonvolatile
853 * CTR volatile
854 * XER volatile
855 * CR0-1 CR5-7 volatile
856 * CR2-4 nonvolatile
857 * Other registers nonvolatile
858 *
859 * The intersection of volatile registers that don't contain possible
860 * inputs is: cr0, xer, ctr. We may use these as scratch regs upon entry
861 * without saving, though xer is not a good idea to use, as hardware may
862 * interpret some bits so it may be costly to change them.
863 */
864#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
865	/*
866	 * There is a little bit of juggling to get syscall and hcall
867	 * working well. Save r13 in ctr to avoid using SPRG scratch
868	 * register.
869	 *
870	 * Userspace syscalls have already saved the PPR, hcalls must save
871	 * it before setting HMT_MEDIUM.
872	 */
873#define SYSCALL_KVMTEST							\
874	mtctr	r13;							\
875	GET_PACA(r13);							\
876	std	r10,PACA_EXGEN+EX_R10(r13);				\
877	KVMTEST_PR(0xc00); /* uses r10, branch to do_kvm_0xc00_system_call */ \
878	HMT_MEDIUM;							\
879	mfctr	r9;
880
881#else
882#define SYSCALL_KVMTEST							\
883	HMT_MEDIUM;							\
884	mr	r9,r13;							\
885	GET_PACA(r13);
886#endif
887
888#define LOAD_SYSCALL_HANDLER(reg)					\
889	__LOAD_HANDLER(reg, system_call_common)
890
891#define SYSCALL_FASTENDIAN_TEST					\
892BEGIN_FTR_SECTION						\
893	cmpdi	r0,0x1ebe ; 					\
894	beq-	1f ;						\
895END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE)				\
896
897/*
898 * After SYSCALL_KVMTEST, we reach here with PACA in r13, r13 in r9,
899 * and HMT_MEDIUM.
900 */
901#define SYSCALL_REAL	 					\
902	mfspr	r11,SPRN_SRR0 ;					\
903	mfspr	r12,SPRN_SRR1 ;					\
904	LOAD_SYSCALL_HANDLER(r10) ; 				\
905	mtspr	SPRN_SRR0,r10 ; 				\
906	ld	r10,PACAKMSR(r13) ;				\
907	mtspr	SPRN_SRR1,r10 ; 				\
908	rfid ; 							\
909	b	. ;	/* prevent speculative execution */
910
911#define SYSCALL_FASTENDIAN					\
912	/* Fast LE/BE switch system call */			\
9131:	mfspr	r12,SPRN_SRR1 ;					\
914	xori	r12,r12,MSR_LE ;				\
915	mtspr	SPRN_SRR1,r12 ;					\
916	mr	r13,r9 ;					\
917	rfid ;		/* return to userspace */		\
918	b	. ;	/* prevent speculative execution */
919
920#if defined(CONFIG_RELOCATABLE)
921	/*
922	 * We can't branch directly so we do it via the CTR which
923	 * is volatile across system calls.
924	 */
925#define SYSCALL_VIRT						\
926	LOAD_SYSCALL_HANDLER(r10) ;				\
927	mtctr	r10 ;						\
928	mfspr	r11,SPRN_SRR0 ;					\
929	mfspr	r12,SPRN_SRR1 ;					\
930	li	r10,MSR_RI ;					\
931	mtmsrd 	r10,1 ;						\
932	bctr ;
933#else
934	/* We can branch directly */
935#define SYSCALL_VIRT						\
936	mfspr	r11,SPRN_SRR0 ;					\
937	mfspr	r12,SPRN_SRR1 ;					\
938	li	r10,MSR_RI ;					\
939	mtmsrd 	r10,1 ;			/* Set RI (EE=0) */	\
940	b	system_call_common ;
941#endif
942
943EXC_REAL_BEGIN(system_call, 0xc00, 0x100)
944	SYSCALL_KVMTEST /* loads PACA into r13, and saves r13 to r9 */
945	SYSCALL_FASTENDIAN_TEST
946	SYSCALL_REAL
947	SYSCALL_FASTENDIAN
948EXC_REAL_END(system_call, 0xc00, 0x100)
949
950EXC_VIRT_BEGIN(system_call, 0x4c00, 0x100)
951	SYSCALL_KVMTEST /* loads PACA into r13, and saves r13 to r9 */
952	SYSCALL_FASTENDIAN_TEST
953	SYSCALL_VIRT
954	SYSCALL_FASTENDIAN
955EXC_VIRT_END(system_call, 0x4c00, 0x100)
956
957#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
958	/*
959	 * This is a hcall, so register convention is as above, with these
960	 * differences:
961	 * r13 = PACA
962	 * ctr = orig r13
963	 * orig r10 saved in PACA
964	 */
965TRAMP_KVM_BEGIN(do_kvm_0xc00)
966	 /*
967	  * Save the PPR (on systems that support it) before changing to
968	  * HMT_MEDIUM. That allows the KVM code to save that value into the
969	  * guest state (it is the guest's PPR value).
970	  */
971	OPT_GET_SPR(r10, SPRN_PPR, CPU_FTR_HAS_PPR)
972	HMT_MEDIUM
973	OPT_SAVE_REG_TO_PACA(PACA_EXGEN+EX_PPR, r10, CPU_FTR_HAS_PPR)
974	mfctr	r10
975	SET_SCRATCH0(r10)
976	std	r9,PACA_EXGEN+EX_R9(r13)
977	mfcr	r9
978	KVM_HANDLER(PACA_EXGEN, EXC_STD, 0xc00)
979#endif
980
981
982EXC_REAL(single_step, 0xd00, 0x100)
983EXC_VIRT(single_step, 0x4d00, 0x100, 0xd00)
984TRAMP_KVM(PACA_EXGEN, 0xd00)
985EXC_COMMON(single_step_common, 0xd00, single_step_exception)
986
987EXC_REAL_OOL_HV(h_data_storage, 0xe00, 0x20)
988EXC_VIRT_OOL_HV(h_data_storage, 0x4e00, 0x20, 0xe00)
989TRAMP_KVM_HV_SKIP(PACA_EXGEN, 0xe00)
990EXC_COMMON_BEGIN(h_data_storage_common)
991	mfspr   r10,SPRN_HDAR
992	std     r10,PACA_EXGEN+EX_DAR(r13)
993	mfspr   r10,SPRN_HDSISR
994	stw     r10,PACA_EXGEN+EX_DSISR(r13)
995	EXCEPTION_PROLOG_COMMON(0xe00, PACA_EXGEN)
996	bl      save_nvgprs
997	RECONCILE_IRQ_STATE(r10, r11)
998	addi    r3,r1,STACK_FRAME_OVERHEAD
999	bl      unknown_exception
1000	b       ret_from_except
1001
1002
1003EXC_REAL_OOL_HV(h_instr_storage, 0xe20, 0x20)
1004EXC_VIRT_OOL_HV(h_instr_storage, 0x4e20, 0x20, 0xe20)
1005TRAMP_KVM_HV(PACA_EXGEN, 0xe20)
1006EXC_COMMON(h_instr_storage_common, 0xe20, unknown_exception)
1007
1008
1009EXC_REAL_OOL_HV(emulation_assist, 0xe40, 0x20)
1010EXC_VIRT_OOL_HV(emulation_assist, 0x4e40, 0x20, 0xe40)
1011TRAMP_KVM_HV(PACA_EXGEN, 0xe40)
1012EXC_COMMON(emulation_assist_common, 0xe40, emulation_assist_interrupt)
1013
1014
1015/*
1016 * hmi_exception trampoline is a special case. It jumps to hmi_exception_early
1017 * first, and then eventaully from there to the trampoline to get into virtual
1018 * mode.
1019 */
1020__EXC_REAL_OOL_HV_DIRECT(hmi_exception, 0xe60, 0x20, hmi_exception_early)
1021__TRAMP_REAL_OOL_MASKABLE_HV(hmi_exception, 0xe60)
1022EXC_VIRT_NONE(0x4e60, 0x20)
1023TRAMP_KVM_HV(PACA_EXGEN, 0xe60)
1024TRAMP_REAL_BEGIN(hmi_exception_early)
1025	EXCEPTION_PROLOG_1(PACA_EXGEN, KVMTEST_HV, 0xe60)
1026	mr	r10,r1			/* Save r1 */
1027	ld	r1,PACAEMERGSP(r13)	/* Use emergency stack for realmode */
1028	subi	r1,r1,INT_FRAME_SIZE	/* alloc stack frame		*/
1029	mfspr	r11,SPRN_HSRR0		/* Save HSRR0 */
1030	mfspr	r12,SPRN_HSRR1		/* Save HSRR1 */
1031	EXCEPTION_PROLOG_COMMON_1()
1032	EXCEPTION_PROLOG_COMMON_2(PACA_EXGEN)
1033	EXCEPTION_PROLOG_COMMON_3(0xe60)
1034	addi	r3,r1,STACK_FRAME_OVERHEAD
1035	BRANCH_LINK_TO_FAR(hmi_exception_realmode) /* Function call ABI */
1036	/* Windup the stack. */
1037	/* Move original HSRR0 and HSRR1 into the respective regs */
1038	ld	r9,_MSR(r1)
1039	mtspr	SPRN_HSRR1,r9
1040	ld	r3,_NIP(r1)
1041	mtspr	SPRN_HSRR0,r3
1042	ld	r9,_CTR(r1)
1043	mtctr	r9
1044	ld	r9,_XER(r1)
1045	mtxer	r9
1046	ld	r9,_LINK(r1)
1047	mtlr	r9
1048	REST_GPR(0, r1)
1049	REST_8GPRS(2, r1)
1050	REST_GPR(10, r1)
1051	ld	r11,_CCR(r1)
1052	mtcr	r11
1053	REST_GPR(11, r1)
1054	REST_2GPRS(12, r1)
1055	/* restore original r1. */
1056	ld	r1,GPR1(r1)
1057
1058	/*
1059	 * Go to virtual mode and pull the HMI event information from
1060	 * firmware.
1061	 */
1062	.globl hmi_exception_after_realmode
1063hmi_exception_after_realmode:
1064	SET_SCRATCH0(r13)
1065	EXCEPTION_PROLOG_0(PACA_EXGEN)
1066	b	tramp_real_hmi_exception
1067
1068EXC_COMMON_ASYNC(hmi_exception_common, 0xe60, handle_hmi_exception)
1069
1070
1071EXC_REAL_OOL_MASKABLE_HV(h_doorbell, 0xe80, 0x20)
1072EXC_VIRT_OOL_MASKABLE_HV(h_doorbell, 0x4e80, 0x20, 0xe80)
1073TRAMP_KVM_HV(PACA_EXGEN, 0xe80)
1074#ifdef CONFIG_PPC_DOORBELL
1075EXC_COMMON_ASYNC(h_doorbell_common, 0xe80, doorbell_exception)
1076#else
1077EXC_COMMON_ASYNC(h_doorbell_common, 0xe80, unknown_exception)
1078#endif
1079
1080
1081EXC_REAL_OOL_MASKABLE_HV(h_virt_irq, 0xea0, 0x20)
1082EXC_VIRT_OOL_MASKABLE_HV(h_virt_irq, 0x4ea0, 0x20, 0xea0)
1083TRAMP_KVM_HV(PACA_EXGEN, 0xea0)
1084EXC_COMMON_ASYNC(h_virt_irq_common, 0xea0, do_IRQ)
1085
1086
1087EXC_REAL_NONE(0xec0, 0x20)
1088EXC_VIRT_NONE(0x4ec0, 0x20)
1089EXC_REAL_NONE(0xee0, 0x20)
1090EXC_VIRT_NONE(0x4ee0, 0x20)
1091
1092
1093EXC_REAL_OOL(performance_monitor, 0xf00, 0x20)
1094EXC_VIRT_OOL(performance_monitor, 0x4f00, 0x20, 0xf00)
1095TRAMP_KVM(PACA_EXGEN, 0xf00)
1096EXC_COMMON_ASYNC(performance_monitor_common, 0xf00, performance_monitor_exception)
1097
1098
1099EXC_REAL_OOL(altivec_unavailable, 0xf20, 0x20)
1100EXC_VIRT_OOL(altivec_unavailable, 0x4f20, 0x20, 0xf20)
1101TRAMP_KVM(PACA_EXGEN, 0xf20)
1102EXC_COMMON_BEGIN(altivec_unavailable_common)
1103	EXCEPTION_PROLOG_COMMON(0xf20, PACA_EXGEN)
1104#ifdef CONFIG_ALTIVEC
1105BEGIN_FTR_SECTION
1106	beq	1f
1107#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1108  BEGIN_FTR_SECTION_NESTED(69)
1109	/* Test if 2 TM state bits are zero.  If non-zero (ie. userspace was in
1110	 * transaction), go do TM stuff
1111	 */
1112	rldicl.	r0, r12, (64-MSR_TS_LG), (64-2)
1113	bne-	2f
1114  END_FTR_SECTION_NESTED(CPU_FTR_TM, CPU_FTR_TM, 69)
1115#endif
1116	bl	load_up_altivec
1117	b	fast_exception_return
1118#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
11192:	/* User process was in a transaction */
1120	bl	save_nvgprs
1121	RECONCILE_IRQ_STATE(r10, r11)
1122	addi	r3,r1,STACK_FRAME_OVERHEAD
1123	bl	altivec_unavailable_tm
1124	b	ret_from_except
1125#endif
11261:
1127END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
1128#endif
1129	bl	save_nvgprs
1130	RECONCILE_IRQ_STATE(r10, r11)
1131	addi	r3,r1,STACK_FRAME_OVERHEAD
1132	bl	altivec_unavailable_exception
1133	b	ret_from_except
1134
1135
1136EXC_REAL_OOL(vsx_unavailable, 0xf40, 0x20)
1137EXC_VIRT_OOL(vsx_unavailable, 0x4f40, 0x20, 0xf40)
1138TRAMP_KVM(PACA_EXGEN, 0xf40)
1139EXC_COMMON_BEGIN(vsx_unavailable_common)
1140	EXCEPTION_PROLOG_COMMON(0xf40, PACA_EXGEN)
1141#ifdef CONFIG_VSX
1142BEGIN_FTR_SECTION
1143	beq	1f
1144#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
1145  BEGIN_FTR_SECTION_NESTED(69)
1146	/* Test if 2 TM state bits are zero.  If non-zero (ie. userspace was in
1147	 * transaction), go do TM stuff
1148	 */
1149	rldicl.	r0, r12, (64-MSR_TS_LG), (64-2)
1150	bne-	2f
1151  END_FTR_SECTION_NESTED(CPU_FTR_TM, CPU_FTR_TM, 69)
1152#endif
1153	b	load_up_vsx
1154#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
11552:	/* User process was in a transaction */
1156	bl	save_nvgprs
1157	RECONCILE_IRQ_STATE(r10, r11)
1158	addi	r3,r1,STACK_FRAME_OVERHEAD
1159	bl	vsx_unavailable_tm
1160	b	ret_from_except
1161#endif
11621:
1163END_FTR_SECTION_IFSET(CPU_FTR_VSX)
1164#endif
1165	bl	save_nvgprs
1166	RECONCILE_IRQ_STATE(r10, r11)
1167	addi	r3,r1,STACK_FRAME_OVERHEAD
1168	bl	vsx_unavailable_exception
1169	b	ret_from_except
1170
1171
1172EXC_REAL_OOL(facility_unavailable, 0xf60, 0x20)
1173EXC_VIRT_OOL(facility_unavailable, 0x4f60, 0x20, 0xf60)
1174TRAMP_KVM(PACA_EXGEN, 0xf60)
1175EXC_COMMON(facility_unavailable_common, 0xf60, facility_unavailable_exception)
1176
1177
1178EXC_REAL_OOL_HV(h_facility_unavailable, 0xf80, 0x20)
1179EXC_VIRT_OOL_HV(h_facility_unavailable, 0x4f80, 0x20, 0xf80)
1180TRAMP_KVM_HV(PACA_EXGEN, 0xf80)
1181EXC_COMMON(h_facility_unavailable_common, 0xf80, facility_unavailable_exception)
1182
1183
1184EXC_REAL_NONE(0xfa0, 0x20)
1185EXC_VIRT_NONE(0x4fa0, 0x20)
1186EXC_REAL_NONE(0xfc0, 0x20)
1187EXC_VIRT_NONE(0x4fc0, 0x20)
1188EXC_REAL_NONE(0xfe0, 0x20)
1189EXC_VIRT_NONE(0x4fe0, 0x20)
1190
1191EXC_REAL_NONE(0x1000, 0x100)
1192EXC_VIRT_NONE(0x5000, 0x100)
1193EXC_REAL_NONE(0x1100, 0x100)
1194EXC_VIRT_NONE(0x5100, 0x100)
1195
1196#ifdef CONFIG_CBE_RAS
1197EXC_REAL_HV(cbe_system_error, 0x1200, 0x100)
1198EXC_VIRT_NONE(0x5200, 0x100)
1199TRAMP_KVM_HV_SKIP(PACA_EXGEN, 0x1200)
1200EXC_COMMON(cbe_system_error_common, 0x1200, cbe_system_error_exception)
1201#else /* CONFIG_CBE_RAS */
1202EXC_REAL_NONE(0x1200, 0x100)
1203EXC_VIRT_NONE(0x5200, 0x100)
1204#endif
1205
1206
1207EXC_REAL(instruction_breakpoint, 0x1300, 0x100)
1208EXC_VIRT(instruction_breakpoint, 0x5300, 0x100, 0x1300)
1209TRAMP_KVM_SKIP(PACA_EXGEN, 0x1300)
1210EXC_COMMON(instruction_breakpoint_common, 0x1300, instruction_breakpoint_exception)
1211
1212EXC_REAL_NONE(0x1400, 0x100)
1213EXC_VIRT_NONE(0x5400, 0x100)
1214
1215EXC_REAL_BEGIN(denorm_exception_hv, 0x1500, 0x100)
1216	mtspr	SPRN_SPRG_HSCRATCH0,r13
1217	EXCEPTION_PROLOG_0(PACA_EXGEN)
1218	EXCEPTION_PROLOG_1(PACA_EXGEN, NOTEST, 0x1500)
1219
1220#ifdef CONFIG_PPC_DENORMALISATION
1221	mfspr	r10,SPRN_HSRR1
1222	mfspr	r11,SPRN_HSRR0		/* save HSRR0 */
1223	andis.	r10,r10,(HSRR1_DENORM)@h /* denorm? */
1224	addi	r11,r11,-4		/* HSRR0 is next instruction */
1225	bne+	denorm_assist
1226#endif
1227
1228	KVMTEST_PR(0x1500)
1229	EXCEPTION_PROLOG_PSERIES_1(denorm_common, EXC_HV)
1230EXC_REAL_END(denorm_exception_hv, 0x1500, 0x100)
1231
1232#ifdef CONFIG_PPC_DENORMALISATION
1233EXC_VIRT_BEGIN(denorm_exception, 0x5500, 0x100)
1234	b	exc_real_0x1500_denorm_exception_hv
1235EXC_VIRT_END(denorm_exception, 0x5500, 0x100)
1236#else
1237EXC_VIRT_NONE(0x5500, 0x100)
1238#endif
1239
1240TRAMP_KVM_SKIP(PACA_EXGEN, 0x1500)
1241
1242#ifdef CONFIG_PPC_DENORMALISATION
1243TRAMP_REAL_BEGIN(denorm_assist)
1244BEGIN_FTR_SECTION
1245/*
1246 * To denormalise we need to move a copy of the register to itself.
1247 * For POWER6 do that here for all FP regs.
1248 */
1249	mfmsr	r10
1250	ori	r10,r10,(MSR_FP|MSR_FE0|MSR_FE1)
1251	xori	r10,r10,(MSR_FE0|MSR_FE1)
1252	mtmsrd	r10
1253	sync
1254
1255#define FMR2(n)  fmr (n), (n) ; fmr n+1, n+1
1256#define FMR4(n)  FMR2(n) ; FMR2(n+2)
1257#define FMR8(n)  FMR4(n) ; FMR4(n+4)
1258#define FMR16(n) FMR8(n) ; FMR8(n+8)
1259#define FMR32(n) FMR16(n) ; FMR16(n+16)
1260	FMR32(0)
1261
1262FTR_SECTION_ELSE
1263/*
1264 * To denormalise we need to move a copy of the register to itself.
1265 * For POWER7 do that here for the first 32 VSX registers only.
1266 */
1267	mfmsr	r10
1268	oris	r10,r10,MSR_VSX@h
1269	mtmsrd	r10
1270	sync
1271
1272#define XVCPSGNDP2(n) XVCPSGNDP(n,n,n) ; XVCPSGNDP(n+1,n+1,n+1)
1273#define XVCPSGNDP4(n) XVCPSGNDP2(n) ; XVCPSGNDP2(n+2)
1274#define XVCPSGNDP8(n) XVCPSGNDP4(n) ; XVCPSGNDP4(n+4)
1275#define XVCPSGNDP16(n) XVCPSGNDP8(n) ; XVCPSGNDP8(n+8)
1276#define XVCPSGNDP32(n) XVCPSGNDP16(n) ; XVCPSGNDP16(n+16)
1277	XVCPSGNDP32(0)
1278
1279ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_206)
1280
1281BEGIN_FTR_SECTION
1282	b	denorm_done
1283END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
1284/*
1285 * To denormalise we need to move a copy of the register to itself.
1286 * For POWER8 we need to do that for all 64 VSX registers
1287 */
1288	XVCPSGNDP32(32)
1289denorm_done:
1290	mtspr	SPRN_HSRR0,r11
1291	mtcrf	0x80,r9
1292	ld	r9,PACA_EXGEN+EX_R9(r13)
1293	RESTORE_PPR_PACA(PACA_EXGEN, r10)
1294BEGIN_FTR_SECTION
1295	ld	r10,PACA_EXGEN+EX_CFAR(r13)
1296	mtspr	SPRN_CFAR,r10
1297END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
1298	ld	r10,PACA_EXGEN+EX_R10(r13)
1299	ld	r11,PACA_EXGEN+EX_R11(r13)
1300	ld	r12,PACA_EXGEN+EX_R12(r13)
1301	ld	r13,PACA_EXGEN+EX_R13(r13)
1302	HRFID
1303	b	.
1304#endif
1305
1306EXC_COMMON_HV(denorm_common, 0x1500, unknown_exception)
1307
1308
1309#ifdef CONFIG_CBE_RAS
1310EXC_REAL_HV(cbe_maintenance, 0x1600, 0x100)
1311EXC_VIRT_NONE(0x5600, 0x100)
1312TRAMP_KVM_HV_SKIP(PACA_EXGEN, 0x1600)
1313EXC_COMMON(cbe_maintenance_common, 0x1600, cbe_maintenance_exception)
1314#else /* CONFIG_CBE_RAS */
1315EXC_REAL_NONE(0x1600, 0x100)
1316EXC_VIRT_NONE(0x5600, 0x100)
1317#endif
1318
1319
1320EXC_REAL(altivec_assist, 0x1700, 0x100)
1321EXC_VIRT(altivec_assist, 0x5700, 0x100, 0x1700)
1322TRAMP_KVM(PACA_EXGEN, 0x1700)
1323#ifdef CONFIG_ALTIVEC
1324EXC_COMMON(altivec_assist_common, 0x1700, altivec_assist_exception)
1325#else
1326EXC_COMMON(altivec_assist_common, 0x1700, unknown_exception)
1327#endif
1328
1329
1330#ifdef CONFIG_CBE_RAS
1331EXC_REAL_HV(cbe_thermal, 0x1800, 0x100)
1332EXC_VIRT_NONE(0x5800, 0x100)
1333TRAMP_KVM_HV_SKIP(PACA_EXGEN, 0x1800)
1334EXC_COMMON(cbe_thermal_common, 0x1800, cbe_thermal_exception)
1335#else /* CONFIG_CBE_RAS */
1336EXC_REAL_NONE(0x1800, 0x100)
1337EXC_VIRT_NONE(0x5800, 0x100)
1338#endif
1339
1340#ifdef CONFIG_PPC_WATCHDOG
1341
1342#define MASKED_DEC_HANDLER_LABEL 3f
1343
1344#define MASKED_DEC_HANDLER(_H)				\
13453: /* soft-nmi */					\
1346	std	r12,PACA_EXGEN+EX_R12(r13);		\
1347	GET_SCRATCH0(r10);				\
1348	std	r10,PACA_EXGEN+EX_R13(r13);		\
1349	EXCEPTION_PROLOG_PSERIES_1(soft_nmi_common, _H)
1350
1351/*
1352 * Branch to soft_nmi_interrupt using the emergency stack. The emergency
1353 * stack is one that is usable by maskable interrupts so long as MSR_EE
1354 * remains off. It is used for recovery when something has corrupted the
1355 * normal kernel stack, for example. The "soft NMI" must not use the process
1356 * stack because we want irq disabled sections to avoid touching the stack
1357 * at all (other than PMU interrupts), so use the emergency stack for this,
1358 * and run it entirely with interrupts hard disabled.
1359 */
1360EXC_COMMON_BEGIN(soft_nmi_common)
1361	mr	r10,r1
1362	ld	r1,PACAEMERGSP(r13)
1363	subi	r1,r1,INT_FRAME_SIZE
1364	EXCEPTION_COMMON_NORET_STACK(PACA_EXGEN, 0x900,
1365			system_reset, soft_nmi_interrupt,
1366			ADD_NVGPRS;ADD_RECONCILE)
1367	b	ret_from_except
1368
1369#else /* CONFIG_PPC_WATCHDOG */
1370#define MASKED_DEC_HANDLER_LABEL 2f /* normal return */
1371#define MASKED_DEC_HANDLER(_H)
1372#endif /* CONFIG_PPC_WATCHDOG */
1373
1374/*
1375 * An interrupt came in while soft-disabled. We set paca->irq_happened, then:
1376 * - If it was a decrementer interrupt, we bump the dec to max and and return.
1377 * - If it was a doorbell we return immediately since doorbells are edge
1378 *   triggered and won't automatically refire.
1379 * - If it was a HMI we return immediately since we handled it in realmode
1380 *   and it won't refire.
1381 * - else we hard disable and return.
1382 * This is called with r10 containing the value to OR to the paca field.
1383 */
1384#define MASKED_INTERRUPT(_H)				\
1385masked_##_H##interrupt:					\
1386	std	r11,PACA_EXGEN+EX_R11(r13);		\
1387	lbz	r11,PACAIRQHAPPENED(r13);		\
1388	or	r11,r11,r10;				\
1389	stb	r11,PACAIRQHAPPENED(r13);		\
1390	cmpwi	r10,PACA_IRQ_DEC;			\
1391	bne	1f;					\
1392	lis	r10,0x7fff;				\
1393	ori	r10,r10,0xffff;				\
1394	mtspr	SPRN_DEC,r10;				\
1395	b	MASKED_DEC_HANDLER_LABEL;		\
13961:	andi.	r10,r10,(PACA_IRQ_DBELL|PACA_IRQ_HMI);	\
1397	bne	2f;					\
1398	mfspr	r10,SPRN_##_H##SRR1;			\
1399	xori	r10,r10,MSR_EE; /* clear MSR_EE */	\
1400	mtspr	SPRN_##_H##SRR1,r10;			\
14012:	mtcrf	0x80,r9;				\
1402	ld	r9,PACA_EXGEN+EX_R9(r13);		\
1403	ld	r10,PACA_EXGEN+EX_R10(r13);		\
1404	ld	r11,PACA_EXGEN+EX_R11(r13);		\
1405	/* returns to kernel where r13 must be set up, so don't restore it */ \
1406	##_H##rfid;					\
1407	b	.;					\
1408	MASKED_DEC_HANDLER(_H)
1409
1410/*
1411 * Real mode exceptions actually use this too, but alternate
1412 * instruction code patches (which end up in the common .text area)
1413 * cannot reach these if they are put there.
1414 */
1415USE_FIXED_SECTION(virt_trampolines)
1416	MASKED_INTERRUPT()
1417	MASKED_INTERRUPT(H)
1418
1419#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
1420TRAMP_REAL_BEGIN(kvmppc_skip_interrupt)
1421	/*
1422	 * Here all GPRs are unchanged from when the interrupt happened
1423	 * except for r13, which is saved in SPRG_SCRATCH0.
1424	 */
1425	mfspr	r13, SPRN_SRR0
1426	addi	r13, r13, 4
1427	mtspr	SPRN_SRR0, r13
1428	GET_SCRATCH0(r13)
1429	rfid
1430	b	.
1431
1432TRAMP_REAL_BEGIN(kvmppc_skip_Hinterrupt)
1433	/*
1434	 * Here all GPRs are unchanged from when the interrupt happened
1435	 * except for r13, which is saved in SPRG_SCRATCH0.
1436	 */
1437	mfspr	r13, SPRN_HSRR0
1438	addi	r13, r13, 4
1439	mtspr	SPRN_HSRR0, r13
1440	GET_SCRATCH0(r13)
1441	hrfid
1442	b	.
1443#endif
1444
1445/*
1446 * Ensure that any handlers that get invoked from the exception prologs
1447 * above are below the first 64KB (0x10000) of the kernel image because
1448 * the prologs assemble the addresses of these handlers using the
1449 * LOAD_HANDLER macro, which uses an ori instruction.
1450 */
1451
1452/*** Common interrupt handlers ***/
1453
1454
1455	/*
1456	 * Relocation-on interrupts: A subset of the interrupts can be delivered
1457	 * with IR=1/DR=1, if AIL==2 and MSR.HV won't be changed by delivering
1458	 * it.  Addresses are the same as the original interrupt addresses, but
1459	 * offset by 0xc000000000004000.
1460	 * It's impossible to receive interrupts below 0x300 via this mechanism.
1461	 * KVM: None of these traps are from the guest ; anything that escalated
1462	 * to HV=1 from HV=0 is delivered via real mode handlers.
1463	 */
1464
1465	/*
1466	 * This uses the standard macro, since the original 0x300 vector
1467	 * only has extra guff for STAB-based processors -- which never
1468	 * come here.
1469	 */
1470
1471EXC_COMMON_BEGIN(ppc64_runlatch_on_trampoline)
1472	b	__ppc64_runlatch_on
1473
1474USE_FIXED_SECTION(virt_trampolines)
1475	/*
1476	 * The __end_interrupts marker must be past the out-of-line (OOL)
1477	 * handlers, so that they are copied to real address 0x100 when running
1478	 * a relocatable kernel. This ensures they can be reached from the short
1479	 * trampoline handlers (like 0x4f00, 0x4f20, etc.) which branch
1480	 * directly, without using LOAD_HANDLER().
1481	 */
1482	.align	7
1483	.globl	__end_interrupts
1484__end_interrupts:
1485DEFINE_FIXED_SYMBOL(__end_interrupts)
1486
1487#ifdef CONFIG_PPC_970_NAP
1488EXC_COMMON_BEGIN(power4_fixup_nap)
1489	andc	r9,r9,r10
1490	std	r9,TI_LOCAL_FLAGS(r11)
1491	ld	r10,_LINK(r1)		/* make idle task do the */
1492	std	r10,_NIP(r1)		/* equivalent of a blr */
1493	blr
1494#endif
1495
1496CLOSE_FIXED_SECTION(real_vectors);
1497CLOSE_FIXED_SECTION(real_trampolines);
1498CLOSE_FIXED_SECTION(virt_vectors);
1499CLOSE_FIXED_SECTION(virt_trampolines);
1500
1501USE_TEXT_SECTION()
1502
1503/*
1504 * Hash table stuff
1505 */
1506	.balign	IFETCH_ALIGN_BYTES
1507do_hash_page:
1508	#ifdef CONFIG_PPC_STD_MMU_64
1509	lis	r0,DSISR_BAD_FAULT_64S@h
1510	ori	r0,r0,DSISR_BAD_FAULT_64S@l
1511	and.	r0,r4,r0		/* weird error? */
1512	bne-	handle_page_fault	/* if not, try to insert a HPTE */
1513	CURRENT_THREAD_INFO(r11, r1)
1514	lwz	r0,TI_PREEMPT(r11)	/* If we're in an "NMI" */
1515	andis.	r0,r0,NMI_MASK@h	/* (i.e. an irq when soft-disabled) */
1516	bne	77f			/* then don't call hash_page now */
1517
1518	/*
1519	 * r3 contains the faulting address
1520	 * r4 msr
1521	 * r5 contains the trap number
1522	 * r6 contains dsisr
1523	 *
1524	 * at return r3 = 0 for success, 1 for page fault, negative for error
1525	 */
1526        mr 	r4,r12
1527	ld      r6,_DSISR(r1)
1528	bl	__hash_page		/* build HPTE if possible */
1529        cmpdi	r3,0			/* see if __hash_page succeeded */
1530
1531	/* Success */
1532	beq	fast_exc_return_irq	/* Return from exception on success */
1533
1534	/* Error */
1535	blt-	13f
1536
1537	/* Reload DSISR into r4 for the DABR check below */
1538	ld      r4,_DSISR(r1)
1539#endif /* CONFIG_PPC_STD_MMU_64 */
1540
1541/* Here we have a page fault that hash_page can't handle. */
1542handle_page_fault:
154311:	andis.  r0,r4,DSISR_DABRMATCH@h
1544	bne-    handle_dabr_fault
1545	ld	r4,_DAR(r1)
1546	ld	r5,_DSISR(r1)
1547	addi	r3,r1,STACK_FRAME_OVERHEAD
1548	bl	do_page_fault
1549	cmpdi	r3,0
1550	beq+	12f
1551	bl	save_nvgprs
1552	mr	r5,r3
1553	addi	r3,r1,STACK_FRAME_OVERHEAD
1554	lwz	r4,_DAR(r1)
1555	bl	bad_page_fault
1556	b	ret_from_except
1557
1558/* We have a data breakpoint exception - handle it */
1559handle_dabr_fault:
1560	bl	save_nvgprs
1561	ld      r4,_DAR(r1)
1562	ld      r5,_DSISR(r1)
1563	addi    r3,r1,STACK_FRAME_OVERHEAD
1564	bl      do_break
156512:	b       ret_from_except_lite
1566
1567
1568#ifdef CONFIG_PPC_STD_MMU_64
1569/* We have a page fault that hash_page could handle but HV refused
1570 * the PTE insertion
1571 */
157213:	bl	save_nvgprs
1573	mr	r5,r3
1574	addi	r3,r1,STACK_FRAME_OVERHEAD
1575	ld	r4,_DAR(r1)
1576	bl	low_hash_fault
1577	b	ret_from_except
1578#endif
1579
1580/*
1581 * We come here as a result of a DSI at a point where we don't want
1582 * to call hash_page, such as when we are accessing memory (possibly
1583 * user memory) inside a PMU interrupt that occurred while interrupts
1584 * were soft-disabled.  We want to invoke the exception handler for
1585 * the access, or panic if there isn't a handler.
1586 */
158777:	bl	save_nvgprs
1588	mr	r4,r3
1589	addi	r3,r1,STACK_FRAME_OVERHEAD
1590	li	r5,SIGSEGV
1591	bl	bad_page_fault
1592	b	ret_from_except
1593
1594/*
1595 * Here we have detected that the kernel stack pointer is bad.
1596 * R9 contains the saved CR, r13 points to the paca,
1597 * r10 contains the (bad) kernel stack pointer,
1598 * r11 and r12 contain the saved SRR0 and SRR1.
1599 * We switch to using an emergency stack, save the registers there,
1600 * and call kernel_bad_stack(), which panics.
1601 */
1602bad_stack:
1603	ld	r1,PACAEMERGSP(r13)
1604	subi	r1,r1,64+INT_FRAME_SIZE
1605	std	r9,_CCR(r1)
1606	std	r10,GPR1(r1)
1607	std	r11,_NIP(r1)
1608	std	r12,_MSR(r1)
1609	mfspr	r11,SPRN_DAR
1610	mfspr	r12,SPRN_DSISR
1611	std	r11,_DAR(r1)
1612	std	r12,_DSISR(r1)
1613	mflr	r10
1614	mfctr	r11
1615	mfxer	r12
1616	std	r10,_LINK(r1)
1617	std	r11,_CTR(r1)
1618	std	r12,_XER(r1)
1619	SAVE_GPR(0,r1)
1620	SAVE_GPR(2,r1)
1621	ld	r10,EX_R3(r3)
1622	std	r10,GPR3(r1)
1623	SAVE_GPR(4,r1)
1624	SAVE_4GPRS(5,r1)
1625	ld	r9,EX_R9(r3)
1626	ld	r10,EX_R10(r3)
1627	SAVE_2GPRS(9,r1)
1628	ld	r9,EX_R11(r3)
1629	ld	r10,EX_R12(r3)
1630	ld	r11,EX_R13(r3)
1631	std	r9,GPR11(r1)
1632	std	r10,GPR12(r1)
1633	std	r11,GPR13(r1)
1634BEGIN_FTR_SECTION
1635	ld	r10,EX_CFAR(r3)
1636	std	r10,ORIG_GPR3(r1)
1637END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
1638	SAVE_8GPRS(14,r1)
1639	SAVE_10GPRS(22,r1)
1640	lhz	r12,PACA_TRAP_SAVE(r13)
1641	std	r12,_TRAP(r1)
1642	addi	r11,r1,INT_FRAME_SIZE
1643	std	r11,0(r1)
1644	li	r12,0
1645	std	r12,0(r11)
1646	ld	r2,PACATOC(r13)
1647	ld	r11,exception_marker@toc(r2)
1648	std	r12,RESULT(r1)
1649	std	r11,STACK_FRAME_OVERHEAD-16(r1)
16501:	addi	r3,r1,STACK_FRAME_OVERHEAD
1651	bl	kernel_bad_stack
1652	b	1b
1653_ASM_NOKPROBE_SYMBOL(bad_stack);
1654
1655/*
1656 * When doorbell is triggered from system reset wakeup, the message is
1657 * not cleared, so it would fire again when EE is enabled.
1658 *
1659 * When coming from local_irq_enable, there may be the same problem if
1660 * we were hard disabled.
1661 *
1662 * Execute msgclr to clear pending exceptions before handling it.
1663 */
1664h_doorbell_common_msgclr:
1665	LOAD_REG_IMMEDIATE(r3, PPC_DBELL_MSGTYPE << (63-36))
1666	PPC_MSGCLR(3)
1667	b 	h_doorbell_common
1668
1669doorbell_super_common_msgclr:
1670	LOAD_REG_IMMEDIATE(r3, PPC_DBELL_MSGTYPE << (63-36))
1671	PPC_MSGCLRP(3)
1672	b 	doorbell_super_common
1673
1674/*
1675 * Called from arch_local_irq_enable when an interrupt needs
1676 * to be resent. r3 contains 0x500, 0x900, 0xa00 or 0xe80 to indicate
1677 * which kind of interrupt. MSR:EE is already off. We generate a
1678 * stackframe like if a real interrupt had happened.
1679 *
1680 * Note: While MSR:EE is off, we need to make sure that _MSR
1681 * in the generated frame has EE set to 1 or the exception
1682 * handler will not properly re-enable them.
1683 *
1684 * Note that we don't specify LR as the NIP (return address) for
1685 * the interrupt because that would unbalance the return branch
1686 * predictor.
1687 */
1688_GLOBAL(__replay_interrupt)
1689	/* We are going to jump to the exception common code which
1690	 * will retrieve various register values from the PACA which
1691	 * we don't give a damn about, so we don't bother storing them.
1692	 */
1693	mfmsr	r12
1694	LOAD_REG_ADDR(r11, replay_interrupt_return)
1695	mfcr	r9
1696	ori	r12,r12,MSR_EE
1697	cmpwi	r3,0x900
1698	beq	decrementer_common
1699	cmpwi	r3,0x500
1700BEGIN_FTR_SECTION
1701	beq	h_virt_irq_common
1702FTR_SECTION_ELSE
1703	beq	hardware_interrupt_common
1704ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_300)
1705BEGIN_FTR_SECTION
1706	cmpwi	r3,0xa00
1707	beq	h_doorbell_common_msgclr
1708	cmpwi	r3,0xe60
1709	beq	hmi_exception_common
1710FTR_SECTION_ELSE
1711	cmpwi	r3,0xa00
1712	beq	doorbell_super_common_msgclr
1713ALT_FTR_SECTION_END_IFSET(CPU_FTR_HVMODE)
1714replay_interrupt_return:
1715	blr
1716
1717_ASM_NOKPROBE_SYMBOL(__replay_interrupt)
1718