summaryrefslogtreecommitdiff
path: root/arch/powerpc/kvm/book3s_interrupts.S
blob: f7ad99d972ce344148fe4c7e05873b1f72aa93aa (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
/* SPDX-License-Identifier: GPL-2.0-only */
/*
 *
 * Copyright SUSE Linux Products GmbH 2009
 *
 * Authors: Alexander Graf <agraf@suse.de>
 */

#include <asm/ppc_asm.h>
#include <asm/kvm_asm.h>
#include <asm/reg.h>
#include <asm/page.h>
#include <asm/asm-offsets.h>
#include <asm/exception-64s.h>
#include <asm/asm-compat.h>

#if defined(CONFIG_PPC_BOOK3S_64)
#ifdef PPC64_ELF_ABI_v2
#define FUNC(name) 		name
#else
#define FUNC(name) 		GLUE(.,name)
#endif
#define GET_SHADOW_VCPU(reg)    addi	reg, r13, PACA_SVCPU

#elif defined(CONFIG_PPC_BOOK3S_32)
#define FUNC(name)		name
#define GET_SHADOW_VCPU(reg)	lwz     reg, (THREAD + THREAD_KVM_SVCPU)(r2)

#endif /* CONFIG_PPC_BOOK3S_XX */

#define VCPU_LOAD_NVGPRS(vcpu) \
	PPC_LL	r14, VCPU_GPR(R14)(vcpu); \
	PPC_LL	r15, VCPU_GPR(R15)(vcpu); \
	PPC_LL	r16, VCPU_GPR(R16)(vcpu); \
	PPC_LL	r17, VCPU_GPR(R17)(vcpu); \
	PPC_LL	r18, VCPU_GPR(R18)(vcpu); \
	PPC_LL	r19, VCPU_GPR(R19)(vcpu); \
	PPC_LL	r20, VCPU_GPR(R20)(vcpu); \
	PPC_LL	r21, VCPU_GPR(R21)(vcpu); \
	PPC_LL	r22, VCPU_GPR(R22)(vcpu); \
	PPC_LL	r23, VCPU_GPR(R23)(vcpu); \
	PPC_LL	r24, VCPU_GPR(R24)(vcpu); \
	PPC_LL	r25, VCPU_GPR(R25)(vcpu); \
	PPC_LL	r26, VCPU_GPR(R26)(vcpu); \
	PPC_LL	r27, VCPU_GPR(R27)(vcpu); \
	PPC_LL	r28, VCPU_GPR(R28)(vcpu); \
	PPC_LL	r29, VCPU_GPR(R29)(vcpu); \
	PPC_LL	r30, VCPU_GPR(R30)(vcpu); \
	PPC_LL	r31, VCPU_GPR(R31)(vcpu); \

/*****************************************************************************
 *                                                                           *
 *     Guest entry / exit code that is in kernel module memory (highmem)     *
 *                                                                           *
 ****************************************************************************/

/* Registers:
 *  r3: kvm_run pointer
 *  r4: vcpu pointer
 */
_GLOBAL(__kvmppc_vcpu_run)

kvm_start_entry:
	/* Write correct stack frame */
	mflr	r0
	PPC_STL	r0,PPC_LR_STKOFF(r1)

	/* Save host state to the stack */
	PPC_STLU r1, -SWITCH_FRAME_SIZE(r1)

	/* Save r3 (kvm_run) and r4 (vcpu) */
	SAVE_2GPRS(3, r1)

	/* Save non-volatile registers (r14 - r31) */
	SAVE_NVGPRS(r1)

	/* Save CR */
	mfcr	r14
	stw	r14, _CCR(r1)

	/* Save LR */
	PPC_STL	r0, _LINK(r1)

	/* Load non-volatile guest state from the vcpu */
	VCPU_LOAD_NVGPRS(r4)

kvm_start_lightweight:
	/* Copy registers into shadow vcpu so we can access them in real mode */
	mr	r3, r4
	bl	FUNC(kvmppc_copy_to_svcpu)
	nop
	REST_GPR(4, r1)

#ifdef CONFIG_PPC_BOOK3S_64
	/* Get the dcbz32 flag */
	PPC_LL	r3, VCPU_HFLAGS(r4)
	rldicl	r3, r3, 0, 63		/* r3 &= 1 */
	stb	r3, HSTATE_RESTORE_HID5(r13)

	/* Load up guest SPRG3 value, since it's user readable */
	lwz	r3, VCPU_SHAREDBE(r4)
	cmpwi	r3, 0
	ld	r5, VCPU_SHARED(r4)
	beq	sprg3_little_endian
sprg3_big_endian:
#ifdef __BIG_ENDIAN__
	ld	r3, VCPU_SHARED_SPRG3(r5)
#else
	addi	r5, r5, VCPU_SHARED_SPRG3
	ldbrx	r3, 0, r5
#endif
	b	after_sprg3_load
sprg3_little_endian:
#ifdef __LITTLE_ENDIAN__
	ld	r3, VCPU_SHARED_SPRG3(r5)
#else
	addi	r5, r5, VCPU_SHARED_SPRG3
	ldbrx	r3, 0, r5
#endif

after_sprg3_load:
	mtspr	SPRN_SPRG3, r3
#endif /* CONFIG_PPC_BOOK3S_64 */

	PPC_LL	r4, VCPU_SHADOW_MSR(r4)	/* get shadow_msr */

	/* Jump to segment patching handler and into our guest */
	bl	FUNC(kvmppc_entry_trampoline)
	nop

/*
 * This is the handler in module memory. It gets jumped at from the
 * lowmem trampoline code, so it's basically the guest exit code.
 *
 */

	/*
	 * Register usage at this point:
	 *
	 * R1       = host R1
	 * R2       = host R2
	 * R12      = exit handler id
	 * R13      = PACA
	 * SVCPU.*  = guest *
	 * MSR.EE   = 1
	 *
	 */

	PPC_LL	r3, GPR4(r1)		/* vcpu pointer */

	/*
	 * kvmppc_copy_from_svcpu can clobber volatile registers, save
	 * the exit handler id to the vcpu and restore it from there later.
	 */
	stw	r12, VCPU_TRAP(r3)

	/* Transfer reg values from shadow vcpu back to vcpu struct */

	bl	FUNC(kvmppc_copy_from_svcpu)
	nop

#ifdef CONFIG_PPC_BOOK3S_64
	/*
	 * Reload kernel SPRG3 value.
	 * No need to save guest value as usermode can't modify SPRG3.
	 */
	ld	r3, PACA_SPRG_VDSO(r13)
	mtspr	SPRN_SPRG_VDSO_WRITE, r3
#endif /* CONFIG_PPC_BOOK3S_64 */

	/* R7 = vcpu */
	PPC_LL	r7, GPR4(r1)

	PPC_STL	r14, VCPU_GPR(R14)(r7)
	PPC_STL	r15, VCPU_GPR(R15)(r7)
	PPC_STL	r16, VCPU_GPR(R16)(r7)
	PPC_STL	r17, VCPU_GPR(R17)(r7)
	PPC_STL	r18, VCPU_GPR(R18)(r7)
	PPC_STL	r19, VCPU_GPR(R19)(r7)
	PPC_STL	r20, VCPU_GPR(R20)(r7)
	PPC_STL	r21, VCPU_GPR(R21)(r7)
	PPC_STL	r22, VCPU_GPR(R22)(r7)
	PPC_STL	r23, VCPU_GPR(R23)(r7)
	PPC_STL	r24, VCPU_GPR(R24)(r7)
	PPC_STL	r25, VCPU_GPR(R25)(r7)
	PPC_STL	r26, VCPU_GPR(R26)(r7)
	PPC_STL	r27, VCPU_GPR(R27)(r7)
	PPC_STL	r28, VCPU_GPR(R28)(r7)
	PPC_STL	r29, VCPU_GPR(R29)(r7)
	PPC_STL	r30, VCPU_GPR(R30)(r7)
	PPC_STL	r31, VCPU_GPR(R31)(r7)

	/* Pass the exit number as 3rd argument to kvmppc_handle_exit */
	lwz	r5, VCPU_TRAP(r7)

	/* Restore r3 (kvm_run) and r4 (vcpu) */
	REST_2GPRS(3, r1)
	bl	FUNC(kvmppc_handle_exit_pr)

	/* If RESUME_GUEST, get back in the loop */
	cmpwi	r3, RESUME_GUEST
	beq	kvm_loop_lightweight

	cmpwi	r3, RESUME_GUEST_NV
	beq	kvm_loop_heavyweight

kvm_exit_loop:

	PPC_LL	r4, _LINK(r1)
	mtlr	r4

	lwz	r14, _CCR(r1)
	mtcr	r14

	/* Restore non-volatile host registers (r14 - r31) */
	REST_NVGPRS(r1)

	addi    r1, r1, SWITCH_FRAME_SIZE
	blr

kvm_loop_heavyweight:

	PPC_LL	r4, _LINK(r1)
	PPC_STL r4, (PPC_LR_STKOFF + SWITCH_FRAME_SIZE)(r1)

	/* Load vcpu and cpu_run */
	REST_2GPRS(3, r1)

	/* Load non-volatile guest state from the vcpu */
	VCPU_LOAD_NVGPRS(r4)

	/* Jump back into the beginning of this function */
	b	kvm_start_lightweight

kvm_loop_lightweight:

	/* We'll need the vcpu pointer */
	REST_GPR(4, r1)

	/* Jump back into the beginning of this function */
	b	kvm_start_lightweight