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#define VCPU_GPR(n)     (VCPU_GPRS + (n * 4))
29
30/* The host stack layout: */
31#define HOST_R1         0 /* Implied by stwu. */
32#define HOST_CALLEE_LR  4
33#define HOST_RUN        8
34/* r2 is special: it holds 'current', and it made nonvolatile in the
35 * kernel with the -ffixed-r2 gcc option. */
36#define HOST_R2         12
37#define HOST_NV_GPRS    16
38#define HOST_NV_GPR(n)  (HOST_NV_GPRS + ((n - 14) * 4))
39#define HOST_MIN_STACK_SIZE (HOST_NV_GPR(31) + 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
56_GLOBAL(kvmppc_handler_\ivor_nr)
57	/* Get pointer to vcpu and record exit number. */
58	mtspr	SPRN_SPRG_WSCRATCH0, r4
59	mfspr	r4, SPRN_SPRG_RVCPU
60	stw	r5, VCPU_GPR(r5)(r4)
61	stw	r6, VCPU_GPR(r6)(r4)
62	mfctr	r5
63	lis	r6, kvmppc_resume_host@h
64	stw	r5, VCPU_CTR(r4)
65	li	r5, \ivor_nr
66	ori	r6, r6, kvmppc_resume_host@l
67	mtctr	r6
68	bctr
69.endm
70
71_GLOBAL(kvmppc_handlers_start)
72KVM_HANDLER BOOKE_INTERRUPT_CRITICAL
73KVM_HANDLER BOOKE_INTERRUPT_MACHINE_CHECK
74KVM_HANDLER BOOKE_INTERRUPT_DATA_STORAGE
75KVM_HANDLER BOOKE_INTERRUPT_INST_STORAGE
76KVM_HANDLER BOOKE_INTERRUPT_EXTERNAL
77KVM_HANDLER BOOKE_INTERRUPT_ALIGNMENT
78KVM_HANDLER BOOKE_INTERRUPT_PROGRAM
79KVM_HANDLER BOOKE_INTERRUPT_FP_UNAVAIL
80KVM_HANDLER BOOKE_INTERRUPT_SYSCALL
81KVM_HANDLER BOOKE_INTERRUPT_AP_UNAVAIL
82KVM_HANDLER BOOKE_INTERRUPT_DECREMENTER
83KVM_HANDLER BOOKE_INTERRUPT_FIT
84KVM_HANDLER BOOKE_INTERRUPT_WATCHDOG
85KVM_HANDLER BOOKE_INTERRUPT_DTLB_MISS
86KVM_HANDLER BOOKE_INTERRUPT_ITLB_MISS
87KVM_HANDLER BOOKE_INTERRUPT_DEBUG
88KVM_HANDLER BOOKE_INTERRUPT_SPE_UNAVAIL
89KVM_HANDLER BOOKE_INTERRUPT_SPE_FP_DATA
90KVM_HANDLER BOOKE_INTERRUPT_SPE_FP_ROUND
91
92_GLOBAL(kvmppc_handler_len)
93	.long kvmppc_handler_1 - kvmppc_handler_0
94
95
96/* Registers:
97 *  SPRG_SCRATCH0: guest r4
98 *  r4: vcpu pointer
99 *  r5: KVM exit number
100 */
101_GLOBAL(kvmppc_resume_host)
102	stw	r3, VCPU_GPR(r3)(r4)
103	mfcr	r3
104	stw	r3, VCPU_CR(r4)
105	stw	r7, VCPU_GPR(r7)(r4)
106	stw	r8, VCPU_GPR(r8)(r4)
107	stw	r9, VCPU_GPR(r9)(r4)
108
109	li	r6, 1
110	slw	r6, r6, r5
111
112#ifdef CONFIG_KVM_EXIT_TIMING
113	/* save exit time */
1141:
115	mfspr	r7, SPRN_TBRU
116	mfspr	r8, SPRN_TBRL
117	mfspr	r9, SPRN_TBRU
118	cmpw	r9, r7
119	bne	1b
120	stw	r8, VCPU_TIMING_EXIT_TBL(r4)
121	stw	r9, VCPU_TIMING_EXIT_TBU(r4)
122#endif
123
124	/* Save the faulting instruction and all GPRs for emulation. */
125	andi.	r7, r6, NEED_INST_MASK
126	beq	..skip_inst_copy
127	mfspr	r9, SPRN_SRR0
128	mfmsr	r8
129	ori	r7, r8, MSR_DS
130	mtmsr	r7
131	isync
132	lwz	r9, 0(r9)
133	mtmsr	r8
134	isync
135	stw	r9, VCPU_LAST_INST(r4)
136
137	stw	r15, VCPU_GPR(r15)(r4)
138	stw	r16, VCPU_GPR(r16)(r4)
139	stw	r17, VCPU_GPR(r17)(r4)
140	stw	r18, VCPU_GPR(r18)(r4)
141	stw	r19, VCPU_GPR(r19)(r4)
142	stw	r20, VCPU_GPR(r20)(r4)
143	stw	r21, VCPU_GPR(r21)(r4)
144	stw	r22, VCPU_GPR(r22)(r4)
145	stw	r23, VCPU_GPR(r23)(r4)
146	stw	r24, VCPU_GPR(r24)(r4)
147	stw	r25, VCPU_GPR(r25)(r4)
148	stw	r26, VCPU_GPR(r26)(r4)
149	stw	r27, VCPU_GPR(r27)(r4)
150	stw	r28, VCPU_GPR(r28)(r4)
151	stw	r29, VCPU_GPR(r29)(r4)
152	stw	r30, VCPU_GPR(r30)(r4)
153	stw	r31, VCPU_GPR(r31)(r4)
154..skip_inst_copy:
155
156	/* Also grab DEAR and ESR before the host can clobber them. */
157
158	andi.	r7, r6, NEED_DEAR_MASK
159	beq	..skip_dear
160	mfspr	r9, SPRN_DEAR
161	stw	r9, VCPU_FAULT_DEAR(r4)
162..skip_dear:
163
164	andi.	r7, r6, NEED_ESR_MASK
165	beq	..skip_esr
166	mfspr	r9, SPRN_ESR
167	stw	r9, VCPU_FAULT_ESR(r4)
168..skip_esr:
169
170	/* Save remaining volatile guest register state to vcpu. */
171	stw	r0, VCPU_GPR(r0)(r4)
172	stw	r1, VCPU_GPR(r1)(r4)
173	stw	r2, VCPU_GPR(r2)(r4)
174	stw	r10, VCPU_GPR(r10)(r4)
175	stw	r11, VCPU_GPR(r11)(r4)
176	stw	r12, VCPU_GPR(r12)(r4)
177	stw	r13, VCPU_GPR(r13)(r4)
178	stw	r14, VCPU_GPR(r14)(r4) /* We need a NV GPR below. */
179	mflr	r3
180	stw	r3, VCPU_LR(r4)
181	mfxer	r3
182	stw	r3, VCPU_XER(r4)
183	mfspr	r3, SPRN_SPRG_RSCRATCH0
184	stw	r3, VCPU_GPR(r4)(r4)
185	mfspr	r3, SPRN_SRR0
186	stw	r3, VCPU_PC(r4)
187
188	/* Restore host stack pointer and PID before IVPR, since the host
189	 * exception handlers use them. */
190	lwz	r1, VCPU_HOST_STACK(r4)
191	lwz	r3, VCPU_HOST_PID(r4)
192	mtspr	SPRN_PID, r3
193
194#ifdef CONFIG_FSL_BOOKE
195	/* we cheat and know that Linux doesn't use PID1 which is always 0 */
196	lis	r3, 0
197	mtspr	SPRN_PID1, r3
198#endif
199
200	/* Restore host IVPR before re-enabling interrupts. We cheat and know
201	 * that Linux IVPR is always 0xc0000000. */
202	lis	r3, 0xc000
203	mtspr	SPRN_IVPR, r3
204
205	/* Switch to kernel stack and jump to handler. */
206	LOAD_REG_ADDR(r3, kvmppc_handle_exit)
207	mtctr	r3
208	lwz	r3, HOST_RUN(r1)
209	lwz	r2, HOST_R2(r1)
210	mr	r14, r4 /* Save vcpu pointer. */
211
212	bctrl	/* kvmppc_handle_exit() */
213
214	/* Restore vcpu pointer and the nonvolatiles we used. */
215	mr	r4, r14
216	lwz	r14, VCPU_GPR(r14)(r4)
217
218	/* Sometimes instruction emulation must restore complete GPR state. */
219	andi.	r5, r3, RESUME_FLAG_NV
220	beq	..skip_nv_load
221	lwz	r15, VCPU_GPR(r15)(r4)
222	lwz	r16, VCPU_GPR(r16)(r4)
223	lwz	r17, VCPU_GPR(r17)(r4)
224	lwz	r18, VCPU_GPR(r18)(r4)
225	lwz	r19, VCPU_GPR(r19)(r4)
226	lwz	r20, VCPU_GPR(r20)(r4)
227	lwz	r21, VCPU_GPR(r21)(r4)
228	lwz	r22, VCPU_GPR(r22)(r4)
229	lwz	r23, VCPU_GPR(r23)(r4)
230	lwz	r24, VCPU_GPR(r24)(r4)
231	lwz	r25, VCPU_GPR(r25)(r4)
232	lwz	r26, VCPU_GPR(r26)(r4)
233	lwz	r27, VCPU_GPR(r27)(r4)
234	lwz	r28, VCPU_GPR(r28)(r4)
235	lwz	r29, VCPU_GPR(r29)(r4)
236	lwz	r30, VCPU_GPR(r30)(r4)
237	lwz	r31, VCPU_GPR(r31)(r4)
238..skip_nv_load:
239
240	/* Should we return to the guest? */
241	andi.	r5, r3, RESUME_FLAG_HOST
242	beq	lightweight_exit
243
244	srawi	r3, r3, 2 /* Shift -ERR back down. */
245
246heavyweight_exit:
247	/* Not returning to guest. */
248
249#ifdef CONFIG_SPE
250	/* save guest SPEFSCR and load host SPEFSCR */
251	mfspr	r9, SPRN_SPEFSCR
252	stw	r9, VCPU_SPEFSCR(r4)
253	lwz	r9, VCPU_HOST_SPEFSCR(r4)
254	mtspr	SPRN_SPEFSCR, r9
255#endif
256
257	/* We already saved guest volatile register state; now save the
258	 * non-volatiles. */
259	stw	r15, VCPU_GPR(r15)(r4)
260	stw	r16, VCPU_GPR(r16)(r4)
261	stw	r17, VCPU_GPR(r17)(r4)
262	stw	r18, VCPU_GPR(r18)(r4)
263	stw	r19, VCPU_GPR(r19)(r4)
264	stw	r20, VCPU_GPR(r20)(r4)
265	stw	r21, VCPU_GPR(r21)(r4)
266	stw	r22, VCPU_GPR(r22)(r4)
267	stw	r23, VCPU_GPR(r23)(r4)
268	stw	r24, VCPU_GPR(r24)(r4)
269	stw	r25, VCPU_GPR(r25)(r4)
270	stw	r26, VCPU_GPR(r26)(r4)
271	stw	r27, VCPU_GPR(r27)(r4)
272	stw	r28, VCPU_GPR(r28)(r4)
273	stw	r29, VCPU_GPR(r29)(r4)
274	stw	r30, VCPU_GPR(r30)(r4)
275	stw	r31, VCPU_GPR(r31)(r4)
276
277	/* Load host non-volatile register state from host stack. */
278	lwz	r14, HOST_NV_GPR(r14)(r1)
279	lwz	r15, HOST_NV_GPR(r15)(r1)
280	lwz	r16, HOST_NV_GPR(r16)(r1)
281	lwz	r17, HOST_NV_GPR(r17)(r1)
282	lwz	r18, HOST_NV_GPR(r18)(r1)
283	lwz	r19, HOST_NV_GPR(r19)(r1)
284	lwz	r20, HOST_NV_GPR(r20)(r1)
285	lwz	r21, HOST_NV_GPR(r21)(r1)
286	lwz	r22, HOST_NV_GPR(r22)(r1)
287	lwz	r23, HOST_NV_GPR(r23)(r1)
288	lwz	r24, HOST_NV_GPR(r24)(r1)
289	lwz	r25, HOST_NV_GPR(r25)(r1)
290	lwz	r26, HOST_NV_GPR(r26)(r1)
291	lwz	r27, HOST_NV_GPR(r27)(r1)
292	lwz	r28, HOST_NV_GPR(r28)(r1)
293	lwz	r29, HOST_NV_GPR(r29)(r1)
294	lwz	r30, HOST_NV_GPR(r30)(r1)
295	lwz	r31, HOST_NV_GPR(r31)(r1)
296
297	/* Return to kvm_vcpu_run(). */
298	lwz	r4, HOST_STACK_LR(r1)
299	addi	r1, r1, HOST_STACK_SIZE
300	mtlr	r4
301	/* r3 still contains the return code from kvmppc_handle_exit(). */
302	blr
303
304
305/* Registers:
306 *  r3: kvm_run pointer
307 *  r4: vcpu pointer
308 */
309_GLOBAL(__kvmppc_vcpu_run)
310	stwu	r1, -HOST_STACK_SIZE(r1)
311	stw	r1, VCPU_HOST_STACK(r4)	/* Save stack pointer to vcpu. */
312
313	/* Save host state to stack. */
314	stw	r3, HOST_RUN(r1)
315	mflr	r3
316	stw	r3, HOST_STACK_LR(r1)
317
318	/* Save host non-volatile register state to stack. */
319	stw	r14, HOST_NV_GPR(r14)(r1)
320	stw	r15, HOST_NV_GPR(r15)(r1)
321	stw	r16, HOST_NV_GPR(r16)(r1)
322	stw	r17, HOST_NV_GPR(r17)(r1)
323	stw	r18, HOST_NV_GPR(r18)(r1)
324	stw	r19, HOST_NV_GPR(r19)(r1)
325	stw	r20, HOST_NV_GPR(r20)(r1)
326	stw	r21, HOST_NV_GPR(r21)(r1)
327	stw	r22, HOST_NV_GPR(r22)(r1)
328	stw	r23, HOST_NV_GPR(r23)(r1)
329	stw	r24, HOST_NV_GPR(r24)(r1)
330	stw	r25, HOST_NV_GPR(r25)(r1)
331	stw	r26, HOST_NV_GPR(r26)(r1)
332	stw	r27, HOST_NV_GPR(r27)(r1)
333	stw	r28, HOST_NV_GPR(r28)(r1)
334	stw	r29, HOST_NV_GPR(r29)(r1)
335	stw	r30, HOST_NV_GPR(r30)(r1)
336	stw	r31, HOST_NV_GPR(r31)(r1)
337
338	/* Load guest non-volatiles. */
339	lwz	r14, VCPU_GPR(r14)(r4)
340	lwz	r15, VCPU_GPR(r15)(r4)
341	lwz	r16, VCPU_GPR(r16)(r4)
342	lwz	r17, VCPU_GPR(r17)(r4)
343	lwz	r18, VCPU_GPR(r18)(r4)
344	lwz	r19, VCPU_GPR(r19)(r4)
345	lwz	r20, VCPU_GPR(r20)(r4)
346	lwz	r21, VCPU_GPR(r21)(r4)
347	lwz	r22, VCPU_GPR(r22)(r4)
348	lwz	r23, VCPU_GPR(r23)(r4)
349	lwz	r24, VCPU_GPR(r24)(r4)
350	lwz	r25, VCPU_GPR(r25)(r4)
351	lwz	r26, VCPU_GPR(r26)(r4)
352	lwz	r27, VCPU_GPR(r27)(r4)
353	lwz	r28, VCPU_GPR(r28)(r4)
354	lwz	r29, VCPU_GPR(r29)(r4)
355	lwz	r30, VCPU_GPR(r30)(r4)
356	lwz	r31, VCPU_GPR(r31)(r4)
357
358#ifdef CONFIG_SPE
359	/* save host SPEFSCR and load guest SPEFSCR */
360	mfspr	r3, SPRN_SPEFSCR
361	stw	r3, VCPU_HOST_SPEFSCR(r4)
362	lwz	r3, VCPU_SPEFSCR(r4)
363	mtspr	SPRN_SPEFSCR, r3
364#endif
365
366lightweight_exit:
367	stw	r2, HOST_R2(r1)
368
369	mfspr	r3, SPRN_PID
370	stw	r3, VCPU_HOST_PID(r4)
371	lwz	r3, VCPU_SHADOW_PID(r4)
372	mtspr	SPRN_PID, r3
373
374#ifdef CONFIG_FSL_BOOKE
375	lwz	r3, VCPU_SHADOW_PID1(r4)
376	mtspr	SPRN_PID1, r3
377#endif
378
379#ifdef CONFIG_44x
380	iccci	0, 0 /* XXX hack */
381#endif
382
383	/* Load some guest volatiles. */
384	lwz	r0, VCPU_GPR(r0)(r4)
385	lwz	r2, VCPU_GPR(r2)(r4)
386	lwz	r9, VCPU_GPR(r9)(r4)
387	lwz	r10, VCPU_GPR(r10)(r4)
388	lwz	r11, VCPU_GPR(r11)(r4)
389	lwz	r12, VCPU_GPR(r12)(r4)
390	lwz	r13, VCPU_GPR(r13)(r4)
391	lwz	r3, VCPU_LR(r4)
392	mtlr	r3
393	lwz	r3, VCPU_XER(r4)
394	mtxer	r3
395
396	/* Switch the IVPR. XXX If we take a TLB miss after this we're screwed,
397	 * so how do we make sure vcpu won't fault? */
398	lis	r8, kvmppc_booke_handlers@ha
399	lwz	r8, kvmppc_booke_handlers@l(r8)
400	mtspr	SPRN_IVPR, r8
401
402	/* Save vcpu pointer for the exception handlers. */
403	mtspr	SPRN_SPRG_WVCPU, r4
404
405	/* Can't switch the stack pointer until after IVPR is switched,
406	 * because host interrupt handlers would get confused. */
407	lwz	r1, VCPU_GPR(r1)(r4)
408
409	/* Host interrupt handlers may have clobbered these guest-readable
410	 * SPRGs, so we need to reload them here with the guest's values. */
411	lwz	r3, VCPU_SPRG4(r4)
412	mtspr	SPRN_SPRG4W, r3
413	lwz	r3, VCPU_SPRG5(r4)
414	mtspr	SPRN_SPRG5W, r3
415	lwz	r3, VCPU_SPRG6(r4)
416	mtspr	SPRN_SPRG6W, r3
417	lwz	r3, VCPU_SPRG7(r4)
418	mtspr	SPRN_SPRG7W, r3
419
420#ifdef CONFIG_KVM_EXIT_TIMING
421	/* save enter time */
4221:
423	mfspr	r6, SPRN_TBRU
424	mfspr	r7, SPRN_TBRL
425	mfspr	r8, SPRN_TBRU
426	cmpw	r8, r6
427	bne	1b
428	stw	r7, VCPU_TIMING_LAST_ENTER_TBL(r4)
429	stw	r8, VCPU_TIMING_LAST_ENTER_TBU(r4)
430#endif
431
432	/* Finish loading guest volatiles and jump to guest. */
433	lwz	r3, VCPU_CTR(r4)
434	lwz	r5, VCPU_CR(r4)
435	lwz	r6, VCPU_PC(r4)
436	lwz	r7, VCPU_SHADOW_MSR(r4)
437	mtctr	r3
438	mtcr	r5
439	mtsrr0	r6
440	mtsrr1	r7
441	lwz	r5, VCPU_GPR(r5)(r4)
442	lwz	r6, VCPU_GPR(r6)(r4)
443	lwz	r7, VCPU_GPR(r7)(r4)
444	lwz	r8, VCPU_GPR(r8)(r4)
445
446	/* Clear any debug events which occurred since we disabled MSR[DE].
447	 * XXX This gives us a 3-instruction window in which a breakpoint
448	 * intended for guest context could fire in the host instead. */
449	lis	r3, 0xffff
450	ori	r3, r3, 0xffff
451	mtspr	SPRN_DBSR, r3
452
453	lwz	r3, VCPU_GPR(r3)(r4)
454	lwz	r4, VCPU_GPR(r4)(r4)
455	rfi
456
457#ifdef CONFIG_SPE
458_GLOBAL(kvmppc_save_guest_spe)
459	cmpi	0,r3,0
460	beqlr-
461	SAVE_32EVRS(0, r4, r3, VCPU_EVR)
462	evxor   evr6, evr6, evr6
463	evmwumiaa evr6, evr6, evr6
464	li	r4,VCPU_ACC
465	evstddx evr6, r4, r3		/* save acc */
466	blr
467
468_GLOBAL(kvmppc_load_guest_spe)
469	cmpi	0,r3,0
470	beqlr-
471	li      r4,VCPU_ACC
472	evlddx  evr6,r4,r3
473	evmra   evr6,evr6		/* load acc */
474	REST_32EVRS(0, r4, r3, VCPU_EVR)
475	blr
476#endif
477