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 SUSE Linux Products GmbH 2009
16 *
17 * Authors: Alexander Graf <agraf@suse.de>
18 */
19
20#include <asm/ppc_asm.h>
21#include <asm/kvm_asm.h>
22#include <asm/reg.h>
23#include <asm/page.h>
24#include <asm/asm-offsets.h>
25#include <asm/exception-64s.h>
26
27#if defined(CONFIG_PPC_BOOK3S_64)
28#define FUNC(name) 		GLUE(.,name)
29#elif defined(CONFIG_PPC_BOOK3S_32)
30#define FUNC(name)		name
31#endif /* CONFIG_PPC_BOOK3S_XX */
32
33#define VCPU_LOAD_NVGPRS(vcpu) \
34	PPC_LL	r14, VCPU_GPR(R14)(vcpu); \
35	PPC_LL	r15, VCPU_GPR(R15)(vcpu); \
36	PPC_LL	r16, VCPU_GPR(R16)(vcpu); \
37	PPC_LL	r17, VCPU_GPR(R17)(vcpu); \
38	PPC_LL	r18, VCPU_GPR(R18)(vcpu); \
39	PPC_LL	r19, VCPU_GPR(R19)(vcpu); \
40	PPC_LL	r20, VCPU_GPR(R20)(vcpu); \
41	PPC_LL	r21, VCPU_GPR(R21)(vcpu); \
42	PPC_LL	r22, VCPU_GPR(R22)(vcpu); \
43	PPC_LL	r23, VCPU_GPR(R23)(vcpu); \
44	PPC_LL	r24, VCPU_GPR(R24)(vcpu); \
45	PPC_LL	r25, VCPU_GPR(R25)(vcpu); \
46	PPC_LL	r26, VCPU_GPR(R26)(vcpu); \
47	PPC_LL	r27, VCPU_GPR(R27)(vcpu); \
48	PPC_LL	r28, VCPU_GPR(R28)(vcpu); \
49	PPC_LL	r29, VCPU_GPR(R29)(vcpu); \
50	PPC_LL	r30, VCPU_GPR(R30)(vcpu); \
51	PPC_LL	r31, VCPU_GPR(R31)(vcpu); \
52
53/*****************************************************************************
54 *                                                                           *
55 *     Guest entry / exit code that is in kernel module memory (highmem)     *
56 *                                                                           *
57 ****************************************************************************/
58
59/* Registers:
60 *  r3: kvm_run pointer
61 *  r4: vcpu pointer
62 */
63_GLOBAL(__kvmppc_vcpu_run)
64
65kvm_start_entry:
66	/* Write correct stack frame */
67	mflr	r0
68	PPC_STL	r0,PPC_LR_STKOFF(r1)
69
70	/* Save host state to the stack */
71	PPC_STLU r1, -SWITCH_FRAME_SIZE(r1)
72
73	/* Save r3 (kvm_run) and r4 (vcpu) */
74	SAVE_2GPRS(3, r1)
75
76	/* Save non-volatile registers (r14 - r31) */
77	SAVE_NVGPRS(r1)
78
79	/* Save CR */
80	mfcr	r14
81	stw	r14, _CCR(r1)
82
83	/* Save LR */
84	PPC_STL	r0, _LINK(r1)
85
86	/* Load non-volatile guest state from the vcpu */
87	VCPU_LOAD_NVGPRS(r4)
88
89kvm_start_lightweight:
90
91#ifdef CONFIG_PPC_BOOK3S_64
92	PPC_LL	r3, VCPU_HFLAGS(r4)
93	rldicl	r3, r3, 0, 63		/* r3 &= 1 */
94	stb	r3, HSTATE_RESTORE_HID5(r13)
95
96	/* Load up guest SPRG3 value, since it's user readable */
97	ld	r3, VCPU_SHARED(r4)
98	ld	r3, VCPU_SHARED_SPRG3(r3)
99	mtspr	SPRN_SPRG3, r3
100#endif /* CONFIG_PPC_BOOK3S_64 */
101
102	PPC_LL	r4, VCPU_SHADOW_MSR(r4)	/* get shadow_msr */
103
104	/* Jump to segment patching handler and into our guest */
105	bl	FUNC(kvmppc_entry_trampoline)
106	nop
107
108/*
109 * This is the handler in module memory. It gets jumped at from the
110 * lowmem trampoline code, so it's basically the guest exit code.
111 *
112 */
113
114.global kvmppc_handler_highmem
115kvmppc_handler_highmem:
116
117	/*
118	 * Register usage at this point:
119	 *
120	 * R1       = host R1
121	 * R2       = host R2
122	 * R12      = exit handler id
123	 * R13      = PACA
124	 * SVCPU.*  = guest *
125	 *
126	 */
127
128	/* R7 = vcpu */
129	PPC_LL	r7, GPR4(r1)
130
131#ifdef CONFIG_PPC_BOOK3S_64
132	/*
133	 * Reload kernel SPRG3 value.
134	 * No need to save guest value as usermode can't modify SPRG3.
135	 */
136	ld	r3, PACA_SPRG3(r13)
137	mtspr	SPRN_SPRG3, r3
138#endif /* CONFIG_PPC_BOOK3S_64 */
139
140	PPC_STL	r14, VCPU_GPR(R14)(r7)
141	PPC_STL	r15, VCPU_GPR(R15)(r7)
142	PPC_STL	r16, VCPU_GPR(R16)(r7)
143	PPC_STL	r17, VCPU_GPR(R17)(r7)
144	PPC_STL	r18, VCPU_GPR(R18)(r7)
145	PPC_STL	r19, VCPU_GPR(R19)(r7)
146	PPC_STL	r20, VCPU_GPR(R20)(r7)
147	PPC_STL	r21, VCPU_GPR(R21)(r7)
148	PPC_STL	r22, VCPU_GPR(R22)(r7)
149	PPC_STL	r23, VCPU_GPR(R23)(r7)
150	PPC_STL	r24, VCPU_GPR(R24)(r7)
151	PPC_STL	r25, VCPU_GPR(R25)(r7)
152	PPC_STL	r26, VCPU_GPR(R26)(r7)
153	PPC_STL	r27, VCPU_GPR(R27)(r7)
154	PPC_STL	r28, VCPU_GPR(R28)(r7)
155	PPC_STL	r29, VCPU_GPR(R29)(r7)
156	PPC_STL	r30, VCPU_GPR(R30)(r7)
157	PPC_STL	r31, VCPU_GPR(R31)(r7)
158
159	/* Pass the exit number as 3rd argument to kvmppc_handle_exit */
160	mr	r5, r12
161
162	/* Restore r3 (kvm_run) and r4 (vcpu) */
163	REST_2GPRS(3, r1)
164	bl	FUNC(kvmppc_handle_exit)
165
166	/* If RESUME_GUEST, get back in the loop */
167	cmpwi	r3, RESUME_GUEST
168	beq	kvm_loop_lightweight
169
170	cmpwi	r3, RESUME_GUEST_NV
171	beq	kvm_loop_heavyweight
172
173kvm_exit_loop:
174
175	PPC_LL	r4, _LINK(r1)
176	mtlr	r4
177
178	lwz	r14, _CCR(r1)
179	mtcr	r14
180
181	/* Restore non-volatile host registers (r14 - r31) */
182	REST_NVGPRS(r1)
183
184	addi    r1, r1, SWITCH_FRAME_SIZE
185	blr
186
187kvm_loop_heavyweight:
188
189	PPC_LL	r4, _LINK(r1)
190	PPC_STL r4, (PPC_LR_STKOFF + SWITCH_FRAME_SIZE)(r1)
191
192	/* Load vcpu and cpu_run */
193	REST_2GPRS(3, r1)
194
195	/* Load non-volatile guest state from the vcpu */
196	VCPU_LOAD_NVGPRS(r4)
197
198	/* Jump back into the beginning of this function */
199	b	kvm_start_lightweight
200
201kvm_loop_lightweight:
202
203	/* We'll need the vcpu pointer */
204	REST_GPR(4, r1)
205
206	/* Jump back into the beginning of this function */
207	b	kvm_start_lightweight
208