1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2018 Andrew Turner
5 *
6 * This software was developed by SRI International and the University of
7 * Cambridge Computer Laboratory under DARPA/AFRL contract FA8750-10-C-0237
8 * ("CTSRD"), as part of the DARPA CRASH research programme.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#include "opt_acpi.h"
33#include "opt_platform.h"
34
35#include <sys/param.h>
36#include <sys/systm.h>
37#include <sys/kernel.h>
38
39#include <dev/psci/psci.h>
40#include <dev/psci/smccc.h>
41
42#define	SMCCC_VERSION_1_0	0x10000
43
44/* Assume 1.0 until we detect a later version */
45static uint32_t	smccc_version;
46
47void
48smccc_init(void)
49{
50	int32_t features;
51	uint32_t ret;
52
53	smccc_version = SMCCC_VERSION_1_0;
54	features = psci_features(SMCCC_VERSION);
55	if (features != PSCI_RETVAL_NOT_SUPPORTED) {
56		ret = psci_call(SMCCC_VERSION, 0, 0, 0);
57		/* This should always be the case as we checked it above */
58		if (ret > 0)
59			smccc_version = ret;
60	}
61
62	if (bootverbose) {
63		printf("Found SMCCC version %u.%u\n",
64		    SMCCC_VERSION_MAJOR(smccc_version),
65		    SMCCC_VERSION_MINOR(smccc_version));
66	}
67}
68
69uint32_t
70smccc_get_version(void)
71{
72	MPASS(smccc_version != 0);
73	return (smccc_version);
74}
75
76int32_t
77smccc_arch_features(uint32_t smccc_func_id)
78{
79
80	MPASS(smccc_version != 0);
81	if (smccc_version == SMCCC_VERSION_1_0)
82		return (PSCI_RETVAL_NOT_SUPPORTED);
83
84	return (psci_call(SMCCC_ARCH_FEATURES, smccc_func_id, 0, 0));
85}
86
87/*
88 * The SMCCC handler for Spectre variant 2: Branch target injection.
89 * (CVE-2017-5715)
90 */
91int
92smccc_arch_workaround_1(void)
93{
94
95	MPASS(smccc_version != 0);
96	KASSERT(smccc_version != SMCCC_VERSION_1_0,
97	    ("SMCCC arch workaround 1 called with an invalid SMCCC interface"));
98	return (psci_call(SMCCC_ARCH_WORKAROUND_1, 0, 0, 0));
99}
100
101int
102smccc_arch_workaround_2(int enable)
103{
104
105	MPASS(smccc_version != 0);
106	KASSERT(smccc_version != SMCCC_VERSION_1_0,
107	    ("SMCCC arch workaround 2 called with an invalid SMCCC interface"));
108	return (psci_call(SMCCC_ARCH_WORKAROUND_2, enable, 0, 0));
109}
110