xref: /linux/include/linux/firmware/trusted_foundations.h (revision 4f2c0a4acffbec01079c28f839422e64ddeff004)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * Copyright (c) 2013, NVIDIA Corporation.
4  */
5 
6 /*
7  * Support for the Trusted Foundations secure monitor.
8  *
9  * Trusted Foundation comes active on some ARM consumer devices (most
10  * Tegra-based devices sold on the market are concerned). Such devices can only
11  * perform some basic operations, like setting the CPU reset vector, through
12  * SMC calls to the secure monitor. The calls are completely specific to
13  * Trusted Foundations, and do *not* follow the SMC calling convention or the
14  * PSCI standard.
15  */
16 
17 #ifndef __FIRMWARE_TRUSTED_FOUNDATIONS_H
18 #define __FIRMWARE_TRUSTED_FOUNDATIONS_H
19 
20 #include <linux/printk.h>
21 #include <linux/bug.h>
22 #include <linux/of.h>
23 #include <linux/cpu.h>
24 #include <linux/smp.h>
25 #include <linux/types.h>
26 
27 #include <asm/hardware/cache-l2x0.h>
28 #include <asm/outercache.h>
29 
30 #define TF_PM_MODE_LP0			0
31 #define TF_PM_MODE_LP1			1
32 #define TF_PM_MODE_LP1_NO_MC_CLK	2
33 #define TF_PM_MODE_LP2			3
34 #define TF_PM_MODE_LP2_NOFLUSH_L2	4
35 #define TF_PM_MODE_NONE			5
36 
37 struct trusted_foundations_platform_data {
38 	unsigned int version_major;
39 	unsigned int version_minor;
40 };
41 
42 #if IS_ENABLED(CONFIG_TRUSTED_FOUNDATIONS)
43 
44 void register_trusted_foundations(struct trusted_foundations_platform_data *pd);
45 void of_register_trusted_foundations(void);
46 bool trusted_foundations_registered(void);
47 
48 #else /* CONFIG_TRUSTED_FOUNDATIONS */
tf_dummy_write_sec(unsigned long val,unsigned int reg)49 static inline void tf_dummy_write_sec(unsigned long val, unsigned int reg)
50 {
51 }
52 
register_trusted_foundations(struct trusted_foundations_platform_data * pd)53 static inline void register_trusted_foundations(
54 				   struct trusted_foundations_platform_data *pd)
55 {
56 	/*
57 	 * If the system requires TF and we cannot provide it, continue booting
58 	 * but disable features that cannot be provided.
59 	 */
60 	pr_err("No support for Trusted Foundations, continuing in degraded mode.\n");
61 	pr_err("Secondary processors as well as CPU PM will be disabled.\n");
62 #if IS_ENABLED(CONFIG_CACHE_L2X0)
63 	pr_err("L2X0 cache will be kept disabled.\n");
64 	outer_cache.write_sec = tf_dummy_write_sec;
65 #endif
66 #if IS_ENABLED(CONFIG_SMP)
67 	setup_max_cpus = 0;
68 #endif
69 	cpu_idle_poll_ctrl(true);
70 }
71 
of_register_trusted_foundations(void)72 static inline void of_register_trusted_foundations(void)
73 {
74 	struct device_node *np = of_find_compatible_node(NULL, NULL, "tlm,trusted-foundations");
75 
76 	if (!np)
77 		return;
78 	of_node_put(np);
79 	/*
80 	 * If we find the target should enable TF but does not support it,
81 	 * fail as the system won't be able to do much anyway
82 	 */
83 	register_trusted_foundations(NULL);
84 }
85 
trusted_foundations_registered(void)86 static inline bool trusted_foundations_registered(void)
87 {
88 	return false;
89 }
90 #endif /* CONFIG_TRUSTED_FOUNDATIONS */
91 
92 #endif
93