1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Trusted Foundations support for ARM CPUs
4  *
5  * Copyright (c) 2013, NVIDIA Corporation.
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/init.h>
10 #include <linux/of.h>
11 
12 #include <linux/firmware/trusted_foundations.h>
13 
14 #include <asm/firmware.h>
15 #include <asm/hardware/cache-l2x0.h>
16 #include <asm/outercache.h>
17 
18 #define TF_CACHE_MAINT		0xfffff100
19 
20 #define TF_CACHE_ENABLE		1
21 #define TF_CACHE_DISABLE	2
22 
23 #define TF_SET_CPU_BOOT_ADDR_SMC 0xfffff200
24 
25 #define TF_CPU_PM		0xfffffffc
26 #define TF_CPU_PM_S3		0xffffffe3
27 #define TF_CPU_PM_S2		0xffffffe6
28 #define TF_CPU_PM_S2_NO_MC_CLK	0xffffffe5
29 #define TF_CPU_PM_S1		0xffffffe4
30 #define TF_CPU_PM_S1_NOFLUSH_L2	0xffffffe7
31 
32 static unsigned long cpu_boot_addr;
33 
34 static void tf_generic_smc(u32 type, u32 arg1, u32 arg2)
35 {
36 	register u32 r0 asm("r0") = type;
37 	register u32 r1 asm("r1") = arg1;
38 	register u32 r2 asm("r2") = arg2;
39 
40 	asm volatile(
41 		".arch_extension	sec\n\t"
42 		"stmfd	sp!, {r4 - r11}\n\t"
43 		__asmeq("%0", "r0")
44 		__asmeq("%1", "r1")
45 		__asmeq("%2", "r2")
46 		"mov	r3, #0\n\t"
47 		"mov	r4, #0\n\t"
48 		"smc	#0\n\t"
49 		"ldmfd	sp!, {r4 - r11}\n\t"
50 		:
51 		: "r" (r0), "r" (r1), "r" (r2)
52 		: "memory", "r3", "r12", "lr");
53 }
54 
55 static int tf_set_cpu_boot_addr(int cpu, unsigned long boot_addr)
56 {
57 	cpu_boot_addr = boot_addr;
58 	tf_generic_smc(TF_SET_CPU_BOOT_ADDR_SMC, cpu_boot_addr, 0);
59 
60 	return 0;
61 }
62 
63 static int tf_prepare_idle(unsigned long mode)
64 {
65 	switch (mode) {
66 	case TF_PM_MODE_LP0:
67 		tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S3, cpu_boot_addr);
68 		break;
69 
70 	case TF_PM_MODE_LP1:
71 		tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S2, cpu_boot_addr);
72 		break;
73 
74 	case TF_PM_MODE_LP1_NO_MC_CLK:
75 		tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S2_NO_MC_CLK,
76 			       cpu_boot_addr);
77 		break;
78 
79 	case TF_PM_MODE_LP2:
80 		tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S1, cpu_boot_addr);
81 		break;
82 
83 	case TF_PM_MODE_LP2_NOFLUSH_L2:
84 		tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S1_NOFLUSH_L2,
85 			       cpu_boot_addr);
86 		break;
87 
88 	default:
89 		return -EINVAL;
90 	}
91 
92 	return 0;
93 }
94 
95 #ifdef CONFIG_CACHE_L2X0
96 static void tf_cache_write_sec(unsigned long val, unsigned int reg)
97 {
98 	u32 l2x0_way_mask = 0xff;
99 
100 	switch (reg) {
101 	case L2X0_CTRL:
102 		if (l2x0_saved_regs.aux_ctrl & L310_AUX_CTRL_ASSOCIATIVITY_16)
103 			l2x0_way_mask = 0xffff;
104 
105 		if (val == L2X0_CTRL_EN)
106 			tf_generic_smc(TF_CACHE_MAINT, TF_CACHE_ENABLE,
107 				       l2x0_saved_regs.aux_ctrl);
108 		else
109 			tf_generic_smc(TF_CACHE_MAINT, TF_CACHE_DISABLE,
110 				       l2x0_way_mask);
111 		break;
112 
113 	default:
114 		break;
115 	}
116 }
117 
118 static int tf_init_cache(void)
119 {
120 	outer_cache.write_sec = tf_cache_write_sec;
121 
122 	return 0;
123 }
124 #endif /* CONFIG_CACHE_L2X0 */
125 
126 static const struct firmware_ops trusted_foundations_ops = {
127 	.set_cpu_boot_addr = tf_set_cpu_boot_addr,
128 	.prepare_idle = tf_prepare_idle,
129 #ifdef CONFIG_CACHE_L2X0
130 	.l2x0_init = tf_init_cache,
131 #endif
132 };
133 
134 void register_trusted_foundations(struct trusted_foundations_platform_data *pd)
135 {
136 	/*
137 	 * we are not using version information for now since currently
138 	 * supported SMCs are compatible with all TF releases
139 	 */
140 	register_firmware_ops(&trusted_foundations_ops);
141 }
142 
143 void of_register_trusted_foundations(void)
144 {
145 	struct device_node *node;
146 	struct trusted_foundations_platform_data pdata;
147 	int err;
148 
149 	node = of_find_compatible_node(NULL, NULL, "tlm,trusted-foundations");
150 	if (!node)
151 		return;
152 
153 	err = of_property_read_u32(node, "tlm,version-major",
154 				   &pdata.version_major);
155 	if (err != 0)
156 		panic("Trusted Foundation: missing version-major property\n");
157 	err = of_property_read_u32(node, "tlm,version-minor",
158 				   &pdata.version_minor);
159 	if (err != 0)
160 		panic("Trusted Foundation: missing version-minor property\n");
161 	register_trusted_foundations(&pdata);
162 }
163 
164 bool trusted_foundations_registered(void)
165 {
166 	return firmware_ops == &trusted_foundations_ops;
167 }
168