1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 *
4 * Copyright SUSE Linux Products GmbH 2009
5 *
6 * Authors: Alexander Graf <agraf@suse.de>
7 */
8
9#include <asm/ppc_asm.h>
10#include <asm/kvm_asm.h>
11#include <asm/reg.h>
12#include <asm/page.h>
13#include <asm/asm-offsets.h>
14#include <asm/exception-64s.h>
15#include <asm/asm-compat.h>
16
17#if defined(CONFIG_PPC_BOOK3S_64)
18#ifdef CONFIG_PPC64_ELF_ABI_V2
19#define FUNC(name) name
20#else
21#define FUNC(name) GLUE(.,name)
22#endif
23#define GET_SHADOW_VCPU(reg) addi reg, r13, PACA_SVCPU
24
25#elif defined(CONFIG_PPC_BOOK3S_32)
26#define FUNC(name) name
27#define GET_SHADOW_VCPU(reg) lwz reg, (THREAD + THREAD_KVM_SVCPU)(r2)
28
29#endif /* CONFIG_PPC_BOOK3S_64 */
30
31#define VCPU_LOAD_NVGPRS(vcpu) \
32 PPC_LL r14, VCPU_GPR(R14)(vcpu); \
33 PPC_LL r15, VCPU_GPR(R15)(vcpu); \
34 PPC_LL r16, VCPU_GPR(R16)(vcpu); \
35 PPC_LL r17, VCPU_GPR(R17)(vcpu); \
36 PPC_LL r18, VCPU_GPR(R18)(vcpu); \
37 PPC_LL r19, VCPU_GPR(R19)(vcpu); \
38 PPC_LL r20, VCPU_GPR(R20)(vcpu); \
39 PPC_LL r21, VCPU_GPR(R21)(vcpu); \
40 PPC_LL r22, VCPU_GPR(R22)(vcpu); \
41 PPC_LL r23, VCPU_GPR(R23)(vcpu); \
42 PPC_LL r24, VCPU_GPR(R24)(vcpu); \
43 PPC_LL r25, VCPU_GPR(R25)(vcpu); \
44 PPC_LL r26, VCPU_GPR(R26)(vcpu); \
45 PPC_LL r27, VCPU_GPR(R27)(vcpu); \
46 PPC_LL r28, VCPU_GPR(R28)(vcpu); \
47 PPC_LL r29, VCPU_GPR(R29)(vcpu); \
48 PPC_LL r30, VCPU_GPR(R30)(vcpu); \
49 PPC_LL r31, VCPU_GPR(R31)(vcpu); \
50
51/*****************************************************************************
52 * *
53 * Guest entry / exit code that is in kernel module memory (highmem) *
54 * *
55 ****************************************************************************/
56
57/* Registers:
58 * r3: vcpu pointer
59 */
60_GLOBAL(__kvmppc_vcpu_run)
61
62kvm_start_entry:
63 /* Write correct stack frame */
64 mflr r0
65 PPC_STL r0,PPC_LR_STKOFF(r1)
66
67 /* Save host state to the stack */
68 PPC_STLU r1, -SWITCH_FRAME_SIZE(r1)
69
70 /* Save r3 (vcpu) */
71 SAVE_GPR(3, r1)
72
73 /* Save non-volatile registers (r14 - r31) */
74 SAVE_NVGPRS(r1)
75
76 /* Save CR */
77 mfcr r14
78 stw r14, _CCR(r1)
79
80 /* Save LR */
81 PPC_STL r0, _LINK(r1)
82
83 /* Load non-volatile guest state from the vcpu */
84 VCPU_LOAD_NVGPRS(r3)
85
86kvm_start_lightweight:
87 /* Copy registers into shadow vcpu so we can access them in real mode */
88 bl FUNC(kvmppc_copy_to_svcpu)
89 nop
90 REST_GPR(3, r1)
91
92#ifdef CONFIG_PPC_BOOK3S_64
93 /* Get the dcbz32 flag */
94 PPC_LL r0, VCPU_HFLAGS(r3)
95 rldicl r0, r0, 0, 63 /* r3 &= 1 */
96 stb r0, HSTATE_RESTORE_HID5(r13)
97
98 /* Load up guest SPRG3 value, since it's user readable */
99 lbz r4, VCPU_SHAREDBE(r3)
100 cmpwi r4, 0
101 ld r5, VCPU_SHARED(r3)
102 beq sprg3_little_endian
103sprg3_big_endian:
104#ifdef __BIG_ENDIAN__
105 ld r4, VCPU_SHARED_SPRG3(r5)
106#else
107 addi r5, r5, VCPU_SHARED_SPRG3
108 ldbrx r4, 0, r5
109#endif
110 b after_sprg3_load
111sprg3_little_endian:
112#ifdef __LITTLE_ENDIAN__
113 ld r4, VCPU_SHARED_SPRG3(r5)
114#else
115 addi r5, r5, VCPU_SHARED_SPRG3
116 ldbrx r4, 0, r5
117#endif
118
119after_sprg3_load:
120 mtspr SPRN_SPRG3, r4
121#endif /* CONFIG_PPC_BOOK3S_64 */
122
123 PPC_LL r4, VCPU_SHADOW_MSR(r3) /* get shadow_msr */
124
125 /* Jump to segment patching handler and into our guest */
126 bl FUNC(kvmppc_entry_trampoline)
127 nop
128
129/*
130 * This is the handler in module memory. It gets jumped at from the
131 * lowmem trampoline code, so it's basically the guest exit code.
132 *
133 */
134
135 /*
136 * Register usage at this point:
137 *
138 * R1 = host R1
139 * R2 = host R2
140 * R12 = exit handler id
141 * R13 = PACA
142 * SVCPU.* = guest *
143 * MSR.EE = 1
144 *
145 */
146
147 PPC_LL r3, GPR3(r1) /* vcpu pointer */
148
149 /*
150 * kvmppc_copy_from_svcpu can clobber volatile registers, save
151 * the exit handler id to the vcpu and restore it from there later.
152 */
153 stw r12, VCPU_TRAP(r3)
154
155 /* Transfer reg values from shadow vcpu back to vcpu struct */
156
157 bl FUNC(kvmppc_copy_from_svcpu)
158 nop
159
160#ifdef CONFIG_PPC_BOOK3S_64
161 /*
162 * Reload kernel SPRG3 value.
163 * No need to save guest value as usermode can't modify SPRG3.
164 */
165 ld r3, PACA_SPRG_VDSO(r13)
166 mtspr SPRN_SPRG_VDSO_WRITE, r3
167#endif /* CONFIG_PPC_BOOK3S_64 */
168
169 /* R7 = vcpu */
170 PPC_LL r7, GPR3(r1)
171
172 PPC_STL r14, VCPU_GPR(R14)(r7)
173 PPC_STL r15, VCPU_GPR(R15)(r7)
174 PPC_STL r16, VCPU_GPR(R16)(r7)
175 PPC_STL r17, VCPU_GPR(R17)(r7)
176 PPC_STL r18, VCPU_GPR(R18)(r7)
177 PPC_STL r19, VCPU_GPR(R19)(r7)
178 PPC_STL r20, VCPU_GPR(R20)(r7)
179 PPC_STL r21, VCPU_GPR(R21)(r7)
180 PPC_STL r22, VCPU_GPR(R22)(r7)
181 PPC_STL r23, VCPU_GPR(R23)(r7)
182 PPC_STL r24, VCPU_GPR(R24)(r7)
183 PPC_STL r25, VCPU_GPR(R25)(r7)
184 PPC_STL r26, VCPU_GPR(R26)(r7)
185 PPC_STL r27, VCPU_GPR(R27)(r7)
186 PPC_STL r28, VCPU_GPR(R28)(r7)
187 PPC_STL r29, VCPU_GPR(R29)(r7)
188 PPC_STL r30, VCPU_GPR(R30)(r7)
189 PPC_STL r31, VCPU_GPR(R31)(r7)
190
191 /* Pass the exit number as 2nd argument to kvmppc_handle_exit */
192 lwz r4, VCPU_TRAP(r7)
193
194 /* Restore r3 (vcpu) */
195 REST_GPR(3, r1)
196 bl FUNC(kvmppc_handle_exit_pr)
197
198 /* If RESUME_GUEST, get back in the loop */
199 cmpwi r3, RESUME_GUEST
200 beq kvm_loop_lightweight
201
202 cmpwi r3, RESUME_GUEST_NV
203 beq kvm_loop_heavyweight
204
205kvm_exit_loop:
206
207 PPC_LL r4, _LINK(r1)
208 mtlr r4
209
210 lwz r14, _CCR(r1)
211 mtcr r14
212
213 /* Restore non-volatile host registers (r14 - r31) */
214 REST_NVGPRS(r1)
215
216 addi r1, r1, SWITCH_FRAME_SIZE
217 blr
218
219kvm_loop_heavyweight:
220
221 PPC_LL r4, _LINK(r1)
222 PPC_STL r4, (PPC_LR_STKOFF + SWITCH_FRAME_SIZE)(r1)
223
224 /* Load vcpu */
225 REST_GPR(3, r1)
226
227 /* Load non-volatile guest state from the vcpu */
228 VCPU_LOAD_NVGPRS(r3)
229
230 /* Jump back into the beginning of this function */
231 b kvm_start_lightweight
232
233kvm_loop_lightweight:
234
235 /* We'll need the vcpu pointer */
236 REST_GPR(3, r1)
237
238 /* Jump back into the beginning of this function */
239 b kvm_start_lightweight
240

source code of linux/arch/powerpc/kvm/book3s_interrupts.S