summaryrefslogtreecommitdiff
path: root/arch/arm64/kvm/hyp/hyp-entry.S
blob: 3488894397ffa528f951a2337c0f12bd5035c089 (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
/*
 * Copyright (C) 2015 - ARM Ltd
 * Author: Marc Zyngier <marc.zyngier@arm.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <linux/linkage.h>

#include <asm/alternative.h>
#include <asm/assembler.h>
#include <asm/cpufeature.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_mmu.h>

	.text
	.pushsection	.hyp.text, "ax"

.macro	save_x0_to_x3
	stp	x0, x1, [sp, #-16]!
	stp	x2, x3, [sp, #-16]!
.endm

.macro	restore_x0_to_x3
	ldp	x2, x3, [sp], #16
	ldp	x0, x1, [sp], #16
.endm

.macro do_el2_call
	/*
	 * Shuffle the parameters before calling the function
	 * pointed to in x0. Assumes parameters in x[1,2,3].
	 */
	sub	sp, sp, #16
	str	lr, [sp]
	mov	lr, x0
	mov	x0, x1
	mov	x1, x2
	mov	x2, x3
	blr	lr
	ldr	lr, [sp]
	add	sp, sp, #16
.endm

ENTRY(__vhe_hyp_call)
	do_el2_call
	/*
	 * We used to rely on having an exception return to get
	 * an implicit isb. In the E2H case, we don't have it anymore.
	 * rather than changing all the leaf functions, just do it here
	 * before returning to the rest of the kernel.
	 */
	isb
	ret
ENDPROC(__vhe_hyp_call)
	
el1_sync:				// Guest trapped into EL2
	save_x0_to_x3

alternative_if_not ARM64_HAS_VIRT_HOST_EXTN
	mrs	x1, esr_el2
alternative_else
	mrs	x1, esr_el1
alternative_endif
	lsr	x2, x1, #ESR_ELx_EC_SHIFT

	cmp	x2, #ESR_ELx_EC_HVC64
	b.ne	el1_trap

	mrs	x3, vttbr_el2		// If vttbr is valid, the 64bit guest
	cbnz	x3, el1_trap		// called HVC

	/* Here, we're pretty sure the host called HVC. */
	restore_x0_to_x3

	/* Check for __hyp_get_vectors */
	cbnz	x0, 1f
	mrs	x0, vbar_el2
	b	2f

1:
	/*
	 * Perform the EL2 call
	 */
	kern_hyp_va	x0
	do_el2_call

2:	eret

el1_trap:
	/*
	 * x1: ESR
	 * x2: ESR_EC
	 */

	/* Guest accessed VFP/SIMD registers, save host, restore Guest */
	cmp	x2, #ESR_ELx_EC_FP_ASIMD
	b.eq	__fpsimd_guest_restore

	mrs	x0, tpidr_el2
	mov	x1, #ARM_EXCEPTION_TRAP
	b	__guest_exit

el1_irq:
	save_x0_to_x3
	mrs	x0, tpidr_el2
	mov	x1, #ARM_EXCEPTION_IRQ
	b	__guest_exit

ENTRY(__hyp_do_panic)
	mov	lr, #(PSR_F_BIT | PSR_I_BIT | PSR_A_BIT | PSR_D_BIT |\
		      PSR_MODE_EL1h)
	msr	spsr_el2, lr
	ldr	lr, =panic
	msr	elr_el2, lr
	eret
ENDPROC(__hyp_do_panic)

.macro invalid_vector	label, target = __hyp_panic
	.align	2
\label:
	b \target
ENDPROC(\label)
.endm

	/* None of these should ever happen */
	invalid_vector	el2t_sync_invalid
	invalid_vector	el2t_irq_invalid
	invalid_vector	el2t_fiq_invalid
	invalid_vector	el2t_error_invalid
	invalid_vector	el2h_sync_invalid
	invalid_vector	el2h_irq_invalid
	invalid_vector	el2h_fiq_invalid
	invalid_vector	el2h_error_invalid
	invalid_vector	el1_sync_invalid
	invalid_vector	el1_irq_invalid
	invalid_vector	el1_fiq_invalid
	invalid_vector	el1_error_invalid

	.ltorg

	.align 11

ENTRY(__kvm_hyp_vector)
	ventry	el2t_sync_invalid		// Synchronous EL2t
	ventry	el2t_irq_invalid		// IRQ EL2t
	ventry	el2t_fiq_invalid		// FIQ EL2t
	ventry	el2t_error_invalid		// Error EL2t

	ventry	el2h_sync_invalid		// Synchronous EL2h
	ventry	el2h_irq_invalid		// IRQ EL2h
	ventry	el2h_fiq_invalid		// FIQ EL2h
	ventry	el2h_error_invalid		// Error EL2h

	ventry	el1_sync			// Synchronous 64-bit EL1
	ventry	el1_irq				// IRQ 64-bit EL1
	ventry	el1_fiq_invalid			// FIQ 64-bit EL1
	ventry	el1_error_invalid		// Error 64-bit EL1

	ventry	el1_sync			// Synchronous 32-bit EL1
	ventry	el1_irq				// IRQ 32-bit EL1
	ventry	el1_fiq_invalid			// FIQ 32-bit EL1
	ventry	el1_error_invalid		// Error 32-bit EL1
ENDPROC(__kvm_hyp_vector)