1 /*
2  * Copyright (c) 2013, NVIDIA Corporation.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; either version 2 of the License, or
7  * (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  */
14 
15 /*
16  * Support for the Trusted Foundations secure monitor.
17  *
18  * Trusted Foundation comes active on some ARM consumer devices (most
19  * Tegra-based devices sold on the market are concerned). Such devices can only
20  * perform some basic operations, like setting the CPU reset vector, through
21  * SMC calls to the secure monitor. The calls are completely specific to
22  * Trusted Foundations, and do *not* follow the SMC calling convention or the
23  * PSCI standard.
24  */
25 
26 #ifndef __ASM_ARM_TRUSTED_FOUNDATIONS_H
27 #define __ASM_ARM_TRUSTED_FOUNDATIONS_H
28 
29 #include <linux/kconfig.h>
30 #include <linux/printk.h>
31 #include <linux/bug.h>
32 #include <linux/of.h>
33 #include <linux/cpu.h>
34 #include <linux/smp.h>
35 
36 struct trusted_foundations_platform_data {
37 	unsigned int version_major;
38 	unsigned int version_minor;
39 };
40 
41 #if IS_ENABLED(CONFIG_TRUSTED_FOUNDATIONS)
42 
43 void register_trusted_foundations(struct trusted_foundations_platform_data *pd);
44 void of_register_trusted_foundations(void);
45 
46 #else /* CONFIG_TRUSTED_FOUNDATIONS */
47 
register_trusted_foundations(struct trusted_foundations_platform_data * pd)48 static inline void register_trusted_foundations(
49 				   struct trusted_foundations_platform_data *pd)
50 {
51 	/*
52 	 * If the system requires TF and we cannot provide it, continue booting
53 	 * but disable features that cannot be provided.
54 	 */
55 	pr_err("No support for Trusted Foundations, continuing in degraded mode.\n");
56 	pr_err("Secondary processors as well as CPU PM will be disabled.\n");
57 #if IS_ENABLED(CONFIG_SMP)
58 	setup_max_cpus = 0;
59 #endif
60 	cpu_idle_poll_ctrl(true);
61 }
62 
of_register_trusted_foundations(void)63 static inline void of_register_trusted_foundations(void)
64 {
65 	/*
66 	 * If we find the target should enable TF but does not support it,
67 	 * fail as the system won't be able to do much anyway
68 	 */
69 	if (of_find_compatible_node(NULL, NULL, "tlm,trusted-foundations"))
70 		register_trusted_foundations(NULL);
71 }
72 #endif /* CONFIG_TRUSTED_FOUNDATIONS */
73 
74 #endif
75