xref: /linux/arch/powerpc/kernel/secure_boot.c (revision 31a6a07eefeb4c84bd6730fbe9e95fd9221712cf)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2019 IBM Corporation
4  * Author: Nayna Jain
5  */
6 #include <linux/types.h>
7 #include <linux/of.h>
8 #include <linux/secure_boot.h>
9 #include <linux/string_choices.h>
10 #include <asm/secure_boot.h>
11 
12 static struct device_node *get_ppc_fw_sb_node(void)
13 {
14 	static const struct of_device_id ids[] = {
15 		{ .compatible = "ibm,secureboot", },
16 		{ .compatible = "ibm,secureboot-v1", },
17 		{ .compatible = "ibm,secureboot-v2", },
18 		{},
19 	};
20 
21 	return of_find_matching_node(NULL, ids);
22 }
23 
24 bool is_ppc_secureboot_enabled(void)
25 {
26 	struct device_node *node;
27 	bool enabled = false;
28 	u32 secureboot;
29 
30 	node = get_ppc_fw_sb_node();
31 	enabled = of_property_read_bool(node, "os-secureboot-enforcing");
32 	of_node_put(node);
33 
34 	if (enabled)
35 		goto out;
36 
37 	node = of_find_node_by_path("/");
38 	if (!of_property_read_u32(node, "ibm,secure-boot", &secureboot))
39 		enabled = (secureboot > 1);
40 	of_node_put(node);
41 
42 out:
43 	pr_info("Secure boot mode %s\n", str_enabled_disabled(enabled));
44 
45 	return enabled;
46 }
47 
48 bool arch_get_secureboot(void)
49 {
50 	return is_ppc_secureboot_enabled();
51 }
52 
53 bool is_ppc_trustedboot_enabled(void)
54 {
55 	struct device_node *node;
56 	bool enabled = false;
57 	u32 trustedboot;
58 
59 	node = get_ppc_fw_sb_node();
60 	enabled = of_property_read_bool(node, "trusted-enabled");
61 	of_node_put(node);
62 
63 	if (enabled)
64 		goto out;
65 
66 	node = of_find_node_by_path("/");
67 	if (!of_property_read_u32(node, "ibm,trusted-boot", &trustedboot))
68 		enabled = (trustedboot > 0);
69 	of_node_put(node);
70 
71 out:
72 	pr_info("Trusted boot mode %s\n", str_enabled_disabled(enabled));
73 
74 	return enabled;
75 }
76