1/*
2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License, version 2, as
4 * published by the Free Software Foundation.
5 *
6 * This program is distributed in the hope that it will be useful,
7 * but WITHOUT ANY WARRANTY; without even the implied warranty of
8 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
9 * GNU General Public License for more details.
10 *
11 * You should have received a copy of the GNU General Public License
12 * along with this program; if not, write to the Free Software
13 * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
14 *
15 * Copyright IBM Corp. 2007
16 * Copyright 2011 Freescale Semiconductor, Inc.
17 *
18 * Authors: Hollis Blanchard <hollisb@us.ibm.com>
19 */
20
21#include <asm/ppc_asm.h>
22#include <asm/kvm_asm.h>
23#include <asm/reg.h>
24#include <asm/mmu-44x.h>
25#include <asm/page.h>
26#include <asm/asm-offsets.h>
27
28/* The host stack layout: */
29#define HOST_R1         0 /* Implied by stwu. */
30#define HOST_CALLEE_LR  4
31#define HOST_RUN        8
32/* r2 is special: it holds 'current', and it made nonvolatile in the
33 * kernel with the -ffixed-r2 gcc option. */
34#define HOST_R2         12
35#define HOST_CR         16
36#define HOST_NV_GPRS    20
37#define __HOST_NV_GPR(n)  (HOST_NV_GPRS + ((n - 14) * 4))
38#define HOST_NV_GPR(n)  __HOST_NV_GPR(__REG_##n)
39#define HOST_MIN_STACK_SIZE (HOST_NV_GPR(R31) + 4)
40#define HOST_STACK_SIZE (((HOST_MIN_STACK_SIZE + 15) / 16) * 16) /* Align. */
41#define HOST_STACK_LR   (HOST_STACK_SIZE + 4) /* In caller stack frame. */
42
43#define NEED_INST_MASK ((1<<BOOKE_INTERRUPT_PROGRAM) | \
44                        (1<<BOOKE_INTERRUPT_DTLB_MISS) | \
45                        (1<<BOOKE_INTERRUPT_DEBUG))
46
47#define NEED_DEAR_MASK ((1<<BOOKE_INTERRUPT_DATA_STORAGE) | \
48                        (1<<BOOKE_INTERRUPT_DTLB_MISS))
49
50#define NEED_ESR_MASK ((1<<BOOKE_INTERRUPT_DATA_STORAGE) | \
51                       (1<<BOOKE_INTERRUPT_INST_STORAGE) | \
52                       (1<<BOOKE_INTERRUPT_PROGRAM) | \
53                       (1<<BOOKE_INTERRUPT_DTLB_MISS))
54
55.macro KVM_HANDLER ivor_nr scratch srr0
56_GLOBAL(kvmppc_handler_\ivor_nr)
57	/* Get pointer to vcpu and record exit number. */
58	mtspr	\scratch , r4
59	mfspr	r4, SPRN_SPRG_RVCPU
60	stw	r3, VCPU_GPR(R3)(r4)
61	stw	r5, VCPU_GPR(R5)(r4)
62	stw	r6, VCPU_GPR(R6)(r4)
63	mfspr	r3, \scratch
64	mfctr	r5
65	stw	r3, VCPU_GPR(R4)(r4)
66	stw	r5, VCPU_CTR(r4)
67	mfspr	r3, \srr0
68	lis	r6, kvmppc_resume_host@h
69	stw	r3, VCPU_PC(r4)
70	li	r5, \ivor_nr
71	ori	r6, r6, kvmppc_resume_host@l
72	mtctr	r6
73	bctr
74.endm
75
76_GLOBAL(kvmppc_handlers_start)
77KVM_HANDLER BOOKE_INTERRUPT_CRITICAL SPRN_SPRG_RSCRATCH_CRIT SPRN_CSRR0
78KVM_HANDLER BOOKE_INTERRUPT_MACHINE_CHECK  SPRN_SPRG_RSCRATCH_MC SPRN_MCSRR0
79KVM_HANDLER BOOKE_INTERRUPT_DATA_STORAGE SPRN_SPRG_RSCRATCH0 SPRN_SRR0
80KVM_HANDLER BOOKE_INTERRUPT_INST_STORAGE SPRN_SPRG_RSCRATCH0 SPRN_SRR0
81KVM_HANDLER BOOKE_INTERRUPT_EXTERNAL SPRN_SPRG_RSCRATCH0 SPRN_SRR0
82KVM_HANDLER BOOKE_INTERRUPT_ALIGNMENT SPRN_SPRG_RSCRATCH0 SPRN_SRR0
83KVM_HANDLER BOOKE_INTERRUPT_PROGRAM SPRN_SPRG_RSCRATCH0 SPRN_SRR0
84KVM_HANDLER BOOKE_INTERRUPT_FP_UNAVAIL SPRN_SPRG_RSCRATCH0 SPRN_SRR0
85KVM_HANDLER BOOKE_INTERRUPT_SYSCALL SPRN_SPRG_RSCRATCH0 SPRN_SRR0
86KVM_HANDLER BOOKE_INTERRUPT_AP_UNAVAIL SPRN_SPRG_RSCRATCH0 SPRN_SRR0
87KVM_HANDLER BOOKE_INTERRUPT_DECREMENTER SPRN_SPRG_RSCRATCH0 SPRN_SRR0
88KVM_HANDLER BOOKE_INTERRUPT_FIT SPRN_SPRG_RSCRATCH0 SPRN_SRR0
89KVM_HANDLER BOOKE_INTERRUPT_WATCHDOG SPRN_SPRG_RSCRATCH_CRIT SPRN_CSRR0
90KVM_HANDLER BOOKE_INTERRUPT_DTLB_MISS SPRN_SPRG_RSCRATCH0 SPRN_SRR0
91KVM_HANDLER BOOKE_INTERRUPT_ITLB_MISS SPRN_SPRG_RSCRATCH0 SPRN_SRR0
92KVM_HANDLER BOOKE_INTERRUPT_DEBUG SPRN_SPRG_RSCRATCH_CRIT SPRN_CSRR0
93KVM_HANDLER BOOKE_INTERRUPT_SPE_UNAVAIL SPRN_SPRG_RSCRATCH0 SPRN_SRR0
94KVM_HANDLER BOOKE_INTERRUPT_SPE_FP_DATA SPRN_SPRG_RSCRATCH0 SPRN_SRR0
95KVM_HANDLER BOOKE_INTERRUPT_SPE_FP_ROUND SPRN_SPRG_RSCRATCH0 SPRN_SRR0
96
97_GLOBAL(kvmppc_handler_len)
98	.long kvmppc_handler_1 - kvmppc_handler_0
99
100/* Registers:
101 *  SPRG_SCRATCH0: guest r4
102 *  r4: vcpu pointer
103 *  r5: KVM exit number
104 */
105_GLOBAL(kvmppc_resume_host)
106	mfcr	r3
107	stw	r3, VCPU_CR(r4)
108	stw	r7, VCPU_GPR(R7)(r4)
109	stw	r8, VCPU_GPR(R8)(r4)
110	stw	r9, VCPU_GPR(R9)(r4)
111
112	li	r6, 1
113	slw	r6, r6, r5
114
115#ifdef CONFIG_KVM_EXIT_TIMING
116	/* save exit time */
1171:
118	mfspr	r7, SPRN_TBRU
119	mfspr	r8, SPRN_TBRL
120	mfspr	r9, SPRN_TBRU
121	cmpw	r9, r7
122	bne	1b
123	stw	r8, VCPU_TIMING_EXIT_TBL(r4)
124	stw	r9, VCPU_TIMING_EXIT_TBU(r4)
125#endif
126
127	/* Save the faulting instruction and all GPRs for emulation. */
128	andi.	r7, r6, NEED_INST_MASK
129	beq	..skip_inst_copy
130	mfspr	r9, SPRN_SRR0
131	mfmsr	r8
132	ori	r7, r8, MSR_DS
133	mtmsr	r7
134	isync
135	lwz	r9, 0(r9)
136	mtmsr	r8
137	isync
138	stw	r9, VCPU_LAST_INST(r4)
139
140	stw	r15, VCPU_GPR(R15)(r4)
141	stw	r16, VCPU_GPR(R16)(r4)
142	stw	r17, VCPU_GPR(R17)(r4)
143	stw	r18, VCPU_GPR(R18)(r4)
144	stw	r19, VCPU_GPR(R19)(r4)
145	stw	r20, VCPU_GPR(R20)(r4)
146	stw	r21, VCPU_GPR(R21)(r4)
147	stw	r22, VCPU_GPR(R22)(r4)
148	stw	r23, VCPU_GPR(R23)(r4)
149	stw	r24, VCPU_GPR(R24)(r4)
150	stw	r25, VCPU_GPR(R25)(r4)
151	stw	r26, VCPU_GPR(R26)(r4)
152	stw	r27, VCPU_GPR(R27)(r4)
153	stw	r28, VCPU_GPR(R28)(r4)
154	stw	r29, VCPU_GPR(R29)(r4)
155	stw	r30, VCPU_GPR(R30)(r4)
156	stw	r31, VCPU_GPR(R31)(r4)
157..skip_inst_copy:
158
159	/* Also grab DEAR and ESR before the host can clobber them. */
160
161	andi.	r7, r6, NEED_DEAR_MASK
162	beq	..skip_dear
163	mfspr	r9, SPRN_DEAR
164	stw	r9, VCPU_FAULT_DEAR(r4)
165..skip_dear:
166
167	andi.	r7, r6, NEED_ESR_MASK
168	beq	..skip_esr
169	mfspr	r9, SPRN_ESR
170	stw	r9, VCPU_FAULT_ESR(r4)
171..skip_esr:
172
173	/* Save remaining volatile guest register state to vcpu. */
174	stw	r0, VCPU_GPR(R0)(r4)
175	stw	r1, VCPU_GPR(R1)(r4)
176	stw	r2, VCPU_GPR(R2)(r4)
177	stw	r10, VCPU_GPR(R10)(r4)
178	stw	r11, VCPU_GPR(R11)(r4)
179	stw	r12, VCPU_GPR(R12)(r4)
180	stw	r13, VCPU_GPR(R13)(r4)
181	stw	r14, VCPU_GPR(R14)(r4) /* We need a NV GPR below. */
182	mflr	r3
183	stw	r3, VCPU_LR(r4)
184	mfxer	r3
185	stw	r3, VCPU_XER(r4)
186
187	/* Restore host stack pointer and PID before IVPR, since the host
188	 * exception handlers use them. */
189	lwz	r1, VCPU_HOST_STACK(r4)
190	lwz	r3, VCPU_HOST_PID(r4)
191	mtspr	SPRN_PID, r3
192
193#ifdef CONFIG_FSL_BOOKE
194	/* we cheat and know that Linux doesn't use PID1 which is always 0 */
195	lis	r3, 0
196	mtspr	SPRN_PID1, r3
197#endif
198
199	/* Restore host IVPR before re-enabling interrupts. We cheat and know
200	 * that Linux IVPR is always 0xc0000000. */
201	lis	r3, 0xc000
202	mtspr	SPRN_IVPR, r3
203
204	/* Switch to kernel stack and jump to handler. */
205	LOAD_REG_ADDR(r3, kvmppc_handle_exit)
206	mtctr	r3
207	lwz	r3, HOST_RUN(r1)
208	lwz	r2, HOST_R2(r1)
209	mr	r14, r4 /* Save vcpu pointer. */
210
211	bctrl	/* kvmppc_handle_exit() */
212
213	/* Restore vcpu pointer and the nonvolatiles we used. */
214	mr	r4, r14
215	lwz	r14, VCPU_GPR(R14)(r4)
216
217	/* Sometimes instruction emulation must restore complete GPR state. */
218	andi.	r5, r3, RESUME_FLAG_NV
219	beq	..skip_nv_load
220	lwz	r15, VCPU_GPR(R15)(r4)
221	lwz	r16, VCPU_GPR(R16)(r4)
222	lwz	r17, VCPU_GPR(R17)(r4)
223	lwz	r18, VCPU_GPR(R18)(r4)
224	lwz	r19, VCPU_GPR(R19)(r4)
225	lwz	r20, VCPU_GPR(R20)(r4)
226	lwz	r21, VCPU_GPR(R21)(r4)
227	lwz	r22, VCPU_GPR(R22)(r4)
228	lwz	r23, VCPU_GPR(R23)(r4)
229	lwz	r24, VCPU_GPR(R24)(r4)
230	lwz	r25, VCPU_GPR(R25)(r4)
231	lwz	r26, VCPU_GPR(R26)(r4)
232	lwz	r27, VCPU_GPR(R27)(r4)
233	lwz	r28, VCPU_GPR(R28)(r4)
234	lwz	r29, VCPU_GPR(R29)(r4)
235	lwz	r30, VCPU_GPR(R30)(r4)
236	lwz	r31, VCPU_GPR(R31)(r4)
237..skip_nv_load:
238
239	/* Should we return to the guest? */
240	andi.	r5, r3, RESUME_FLAG_HOST
241	beq	lightweight_exit
242
243	srawi	r3, r3, 2 /* Shift -ERR back down. */
244
245heavyweight_exit:
246	/* Not returning to guest. */
247
248#ifdef CONFIG_SPE
249	/* save guest SPEFSCR and load host SPEFSCR */
250	mfspr	r9, SPRN_SPEFSCR
251	stw	r9, VCPU_SPEFSCR(r4)
252	lwz	r9, VCPU_HOST_SPEFSCR(r4)
253	mtspr	SPRN_SPEFSCR, r9
254#endif
255
256	/* We already saved guest volatile register state; now save the
257	 * non-volatiles. */
258	stw	r15, VCPU_GPR(R15)(r4)
259	stw	r16, VCPU_GPR(R16)(r4)
260	stw	r17, VCPU_GPR(R17)(r4)
261	stw	r18, VCPU_GPR(R18)(r4)
262	stw	r19, VCPU_GPR(R19)(r4)
263	stw	r20, VCPU_GPR(R20)(r4)
264	stw	r21, VCPU_GPR(R21)(r4)
265	stw	r22, VCPU_GPR(R22)(r4)
266	stw	r23, VCPU_GPR(R23)(r4)
267	stw	r24, VCPU_GPR(R24)(r4)
268	stw	r25, VCPU_GPR(R25)(r4)
269	stw	r26, VCPU_GPR(R26)(r4)
270	stw	r27, VCPU_GPR(R27)(r4)
271	stw	r28, VCPU_GPR(R28)(r4)
272	stw	r29, VCPU_GPR(R29)(r4)
273	stw	r30, VCPU_GPR(R30)(r4)
274	stw	r31, VCPU_GPR(R31)(r4)
275
276	/* Load host non-volatile register state from host stack. */
277	lwz	r14, HOST_NV_GPR(R14)(r1)
278	lwz	r15, HOST_NV_GPR(R15)(r1)
279	lwz	r16, HOST_NV_GPR(R16)(r1)
280	lwz	r17, HOST_NV_GPR(R17)(r1)
281	lwz	r18, HOST_NV_GPR(R18)(r1)
282	lwz	r19, HOST_NV_GPR(R19)(r1)
283	lwz	r20, HOST_NV_GPR(R20)(r1)
284	lwz	r21, HOST_NV_GPR(R21)(r1)
285	lwz	r22, HOST_NV_GPR(R22)(r1)
286	lwz	r23, HOST_NV_GPR(R23)(r1)
287	lwz	r24, HOST_NV_GPR(R24)(r1)
288	lwz	r25, HOST_NV_GPR(R25)(r1)
289	lwz	r26, HOST_NV_GPR(R26)(r1)
290	lwz	r27, HOST_NV_GPR(R27)(r1)
291	lwz	r28, HOST_NV_GPR(R28)(r1)
292	lwz	r29, HOST_NV_GPR(R29)(r1)
293	lwz	r30, HOST_NV_GPR(R30)(r1)
294	lwz	r31, HOST_NV_GPR(R31)(r1)
295
296	/* Return to kvm_vcpu_run(). */
297	lwz	r4, HOST_STACK_LR(r1)
298	lwz	r5, HOST_CR(r1)
299	addi	r1, r1, HOST_STACK_SIZE
300	mtlr	r4
301	mtcr	r5
302	/* r3 still contains the return code from kvmppc_handle_exit(). */
303	blr
304
305
306/* Registers:
307 *  r3: kvm_run pointer
308 *  r4: vcpu pointer
309 */
310_GLOBAL(__kvmppc_vcpu_run)
311	stwu	r1, -HOST_STACK_SIZE(r1)
312	stw	r1, VCPU_HOST_STACK(r4)	/* Save stack pointer to vcpu. */
313
314	/* Save host state to stack. */
315	stw	r3, HOST_RUN(r1)
316	mflr	r3
317	stw	r3, HOST_STACK_LR(r1)
318	mfcr	r5
319	stw	r5, HOST_CR(r1)
320
321	/* Save host non-volatile register state to stack. */
322	stw	r14, HOST_NV_GPR(R14)(r1)
323	stw	r15, HOST_NV_GPR(R15)(r1)
324	stw	r16, HOST_NV_GPR(R16)(r1)
325	stw	r17, HOST_NV_GPR(R17)(r1)
326	stw	r18, HOST_NV_GPR(R18)(r1)
327	stw	r19, HOST_NV_GPR(R19)(r1)
328	stw	r20, HOST_NV_GPR(R20)(r1)
329	stw	r21, HOST_NV_GPR(R21)(r1)
330	stw	r22, HOST_NV_GPR(R22)(r1)
331	stw	r23, HOST_NV_GPR(R23)(r1)
332	stw	r24, HOST_NV_GPR(R24)(r1)
333	stw	r25, HOST_NV_GPR(R25)(r1)
334	stw	r26, HOST_NV_GPR(R26)(r1)
335	stw	r27, HOST_NV_GPR(R27)(r1)
336	stw	r28, HOST_NV_GPR(R28)(r1)
337	stw	r29, HOST_NV_GPR(R29)(r1)
338	stw	r30, HOST_NV_GPR(R30)(r1)
339	stw	r31, HOST_NV_GPR(R31)(r1)
340
341	/* Load guest non-volatiles. */
342	lwz	r14, VCPU_GPR(R14)(r4)
343	lwz	r15, VCPU_GPR(R15)(r4)
344	lwz	r16, VCPU_GPR(R16)(r4)
345	lwz	r17, VCPU_GPR(R17)(r4)
346	lwz	r18, VCPU_GPR(R18)(r4)
347	lwz	r19, VCPU_GPR(R19)(r4)
348	lwz	r20, VCPU_GPR(R20)(r4)
349	lwz	r21, VCPU_GPR(R21)(r4)
350	lwz	r22, VCPU_GPR(R22)(r4)
351	lwz	r23, VCPU_GPR(R23)(r4)
352	lwz	r24, VCPU_GPR(R24)(r4)
353	lwz	r25, VCPU_GPR(R25)(r4)
354	lwz	r26, VCPU_GPR(R26)(r4)
355	lwz	r27, VCPU_GPR(R27)(r4)
356	lwz	r28, VCPU_GPR(R28)(r4)
357	lwz	r29, VCPU_GPR(R29)(r4)
358	lwz	r30, VCPU_GPR(R30)(r4)
359	lwz	r31, VCPU_GPR(R31)(r4)
360
361#ifdef CONFIG_SPE
362	/* save host SPEFSCR and load guest SPEFSCR */
363	mfspr	r3, SPRN_SPEFSCR
364	stw	r3, VCPU_HOST_SPEFSCR(r4)
365	lwz	r3, VCPU_SPEFSCR(r4)
366	mtspr	SPRN_SPEFSCR, r3
367#endif
368
369lightweight_exit:
370	stw	r2, HOST_R2(r1)
371
372	mfspr	r3, SPRN_PID
373	stw	r3, VCPU_HOST_PID(r4)
374	lwz	r3, VCPU_SHADOW_PID(r4)
375	mtspr	SPRN_PID, r3
376
377#ifdef CONFIG_FSL_BOOKE
378	lwz	r3, VCPU_SHADOW_PID1(r4)
379	mtspr	SPRN_PID1, r3
380#endif
381
382#ifdef CONFIG_44x
383	iccci	0, 0 /* XXX hack */
384#endif
385
386	/* Load some guest volatiles. */
387	lwz	r0, VCPU_GPR(R0)(r4)
388	lwz	r2, VCPU_GPR(R2)(r4)
389	lwz	r9, VCPU_GPR(R9)(r4)
390	lwz	r10, VCPU_GPR(R10)(r4)
391	lwz	r11, VCPU_GPR(R11)(r4)
392	lwz	r12, VCPU_GPR(R12)(r4)
393	lwz	r13, VCPU_GPR(R13)(r4)
394	lwz	r3, VCPU_LR(r4)
395	mtlr	r3
396	lwz	r3, VCPU_XER(r4)
397	mtxer	r3
398
399	/* Switch the IVPR. XXX If we take a TLB miss after this we're screwed,
400	 * so how do we make sure vcpu won't fault? */
401	lis	r8, kvmppc_booke_handlers@ha
402	lwz	r8, kvmppc_booke_handlers@l(r8)
403	mtspr	SPRN_IVPR, r8
404
405	/* Save vcpu pointer for the exception handlers. */
406	mtspr	SPRN_SPRG_WVCPU, r4
407
408	lwz	r5, VCPU_SHARED(r4)
409
410	/* Can't switch the stack pointer until after IVPR is switched,
411	 * because host interrupt handlers would get confused. */
412	lwz	r1, VCPU_GPR(R1)(r4)
413
414	/*
415	 * Host interrupt handlers may have clobbered these
416	 * guest-readable SPRGs, or the guest kernel may have
417	 * written directly to the shared area, so we
418	 * need to reload them here with the guest's values.
419	 */
420	PPC_LD(r3, VCPU_SHARED_SPRG4, r5)
421	mtspr	SPRN_SPRG4W, r3
422	PPC_LD(r3, VCPU_SHARED_SPRG5, r5)
423	mtspr	SPRN_SPRG5W, r3
424	PPC_LD(r3, VCPU_SHARED_SPRG6, r5)
425	mtspr	SPRN_SPRG6W, r3
426	PPC_LD(r3, VCPU_SHARED_SPRG7, r5)
427	mtspr	SPRN_SPRG7W, r3
428
429#ifdef CONFIG_KVM_EXIT_TIMING
430	/* save enter time */
4311:
432	mfspr	r6, SPRN_TBRU
433	mfspr	r7, SPRN_TBRL
434	mfspr	r8, SPRN_TBRU
435	cmpw	r8, r6
436	bne	1b
437	stw	r7, VCPU_TIMING_LAST_ENTER_TBL(r4)
438	stw	r8, VCPU_TIMING_LAST_ENTER_TBU(r4)
439#endif
440
441	/* Finish loading guest volatiles and jump to guest. */
442	lwz	r3, VCPU_CTR(r4)
443	lwz	r5, VCPU_CR(r4)
444	lwz	r6, VCPU_PC(r4)
445	lwz	r7, VCPU_SHADOW_MSR(r4)
446	mtctr	r3
447	mtcr	r5
448	mtsrr0	r6
449	mtsrr1	r7
450	lwz	r5, VCPU_GPR(R5)(r4)
451	lwz	r6, VCPU_GPR(R6)(r4)
452	lwz	r7, VCPU_GPR(R7)(r4)
453	lwz	r8, VCPU_GPR(R8)(r4)
454
455	/* Clear any debug events which occurred since we disabled MSR[DE].
456	 * XXX This gives us a 3-instruction window in which a breakpoint
457	 * intended for guest context could fire in the host instead. */
458	lis	r3, 0xffff
459	ori	r3, r3, 0xffff
460	mtspr	SPRN_DBSR, r3
461
462	lwz	r3, VCPU_GPR(R3)(r4)
463	lwz	r4, VCPU_GPR(R4)(r4)
464	rfi
465
466#ifdef CONFIG_SPE
467_GLOBAL(kvmppc_save_guest_spe)
468	cmpi	0,r3,0
469	beqlr-
470	SAVE_32EVRS(0, r4, r3, VCPU_EVR)
471	evxor   evr6, evr6, evr6
472	evmwumiaa evr6, evr6, evr6
473	li	r4,VCPU_ACC
474	evstddx evr6, r4, r3		/* save acc */
475	blr
476
477_GLOBAL(kvmppc_load_guest_spe)
478	cmpi	0,r3,0
479	beqlr-
480	li      r4,VCPU_ACC
481	evlddx  evr6,r4,r3
482	evmra   evr6,evr6		/* load acc */
483	REST_32EVRS(0, r4, r3, VCPU_EVR)
484	blr
485#endif
486