xref: /freebsd/sys/arm/arm/hypervisor-stub.S (revision d29771a722acf17b3d2693e237c0da7ce866997f)
1/*
2 * Copyright (C) 2015 Mihai Carabas <mihai.carabas@gmail.com>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include "assym.inc"
28#include <sys/syscall.h>
29#include <machine/asm.h>
30#include <machine/asmacros.h>
31#include <machine/armreg.h>
32#include <machine/sysreg.h>
33#if defined(__ARM_ARCH_7VE__) || defined(__clang__)
34.arch_extension virt
35#endif
36
37ASENTRY_NP(hypervisor_stub_vect_install)
38
39	/* Install hypervisor stub vectors. */
40	adr	r0, hypervisor_stub_vect
41	mcr	CP15_HVBAR(r0)
42
43	/* Disable all the traps in the hypervisor. */
44	mov	r0, #0
45	mcr	CP15_HCR(r0)
46	mcr	CP15_HCPTR(r0)
47	mcr	CP15_HSTR(r0)
48	mcr	CP15_HSCTLR(r0)
49
50	/* Don't disable access to perf-mon from PL0,1 and preserve HPMN. */
51	mrc	CP15_HDCR(r0)
52	and	r0, #(ARM_CP15_HDCR_HPMN)
53	/*  Caller implicit instruction barrier in the ERET. */
54	mcr	CP15_HDCR(r0)
55
56	RET
57
58END(hypervisor_stub_vect_install)
59
60ASENTRY_NP(hypervisor_stub_trap)
61	/*
62	 * If the first parameter is -1 than return the
63	 * exception vector (HVBAR), otherwise set it to
64	 * the value of it.
65	 */
66	cmp	r0, #-1
67	mrceq	CP15_HVBAR(r0)
68	mcrne	CP15_HVBAR(r0)
69	ERET
70END(hypervisor_stub_trap)
71
72	.globl hypervisor_stub_vect
73	.align 5
74_C_LABEL(hypervisor_stub_vect):
75	.word 0 /* Reset */
76	.word 0 /* undev */
77	.word 0 /* SMC */
78	.word 0 /* PABT */
79	.word 0 /* DABT */
80	b	hypervisor_stub_trap /* HYP-Mode */
81	.word 0 /* FIQ */
82	.word 0 /* IRQ */
83
84