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 #define TF_CACHE_REENABLE	4
23 
24 #define TF_SET_CPU_BOOT_ADDR_SMC 0xfffff200
25 
26 #define TF_CPU_PM		0xfffffffc
27 #define TF_CPU_PM_S3		0xffffffe3
28 #define TF_CPU_PM_S2		0xffffffe6
29 #define TF_CPU_PM_S2_NO_MC_CLK	0xffffffe5
30 #define TF_CPU_PM_S1		0xffffffe4
31 #define TF_CPU_PM_S1_NOFLUSH_L2	0xffffffe7
32 
33 static unsigned long tf_idle_mode = TF_PM_MODE_NONE;
34 static unsigned long cpu_boot_addr;
35 
36 static void tf_generic_smc(u32 type, u32 arg1, u32 arg2)
37 {
38 	register u32 r0 asm("r0") = type;
39 	register u32 r1 asm("r1") = arg1;
40 	register u32 r2 asm("r2") = arg2;
41 
42 	asm volatile(
43 		".arch_extension	sec\n\t"
44 		"stmfd	sp!, {r4 - r11}\n\t"
45 		__asmeq("%0", "r0")
46 		__asmeq("%1", "r1")
47 		__asmeq("%2", "r2")
48 		"mov	r3, #0\n\t"
49 		"mov	r4, #0\n\t"
50 		"smc	#0\n\t"
51 		"ldmfd	sp!, {r4 - r11}\n\t"
52 		:
53 		: "r" (r0), "r" (r1), "r" (r2)
54 		: "memory", "r3", "r12", "lr");
55 }
56 
57 static int tf_set_cpu_boot_addr(int cpu, unsigned long boot_addr)
58 {
59 	cpu_boot_addr = boot_addr;
60 	tf_generic_smc(TF_SET_CPU_BOOT_ADDR_SMC, cpu_boot_addr, 0);
61 
62 	return 0;
63 }
64 
65 static int tf_prepare_idle(unsigned long mode)
66 {
67 	switch (mode) {
68 	case TF_PM_MODE_LP0:
69 		tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S3, cpu_boot_addr);
70 		break;
71 
72 	case TF_PM_MODE_LP1:
73 		tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S2, cpu_boot_addr);
74 		break;
75 
76 	case TF_PM_MODE_LP1_NO_MC_CLK:
77 		tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S2_NO_MC_CLK,
78 			       cpu_boot_addr);
79 		break;
80 
81 	case TF_PM_MODE_LP2:
82 		tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S1, cpu_boot_addr);
83 		break;
84 
85 	case TF_PM_MODE_LP2_NOFLUSH_L2:
86 		tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S1_NOFLUSH_L2,
87 			       cpu_boot_addr);
88 		break;
89 
90 	case TF_PM_MODE_NONE:
91 		break;
92 
93 	default:
94 		return -EINVAL;
95 	}
96 
97 	tf_idle_mode = mode;
98 
99 	return 0;
100 }
101 
102 #ifdef CONFIG_CACHE_L2X0
103 static void tf_cache_write_sec(unsigned long val, unsigned int reg)
104 {
105 	u32 enable_op, l2x0_way_mask = 0xff;
106 
107 	switch (reg) {
108 	case L2X0_CTRL:
109 		if (l2x0_saved_regs.aux_ctrl & L310_AUX_CTRL_ASSOCIATIVITY_16)
110 			l2x0_way_mask = 0xffff;
111 
112 		switch (tf_idle_mode) {
113 		case TF_PM_MODE_LP2:
114 			enable_op = TF_CACHE_REENABLE;
115 			break;
116 
117 		default:
118 			enable_op = TF_CACHE_ENABLE;
119 			break;
120 		}
121 
122 		if (val == L2X0_CTRL_EN)
123 			tf_generic_smc(TF_CACHE_MAINT, enable_op,
124 				       l2x0_saved_regs.aux_ctrl);
125 		else
126 			tf_generic_smc(TF_CACHE_MAINT, TF_CACHE_DISABLE,
127 				       l2x0_way_mask);
128 		break;
129 
130 	default:
131 		break;
132 	}
133 }
134 
135 static int tf_init_cache(void)
136 {
137 	outer_cache.write_sec = tf_cache_write_sec;
138 
139 	return 0;
140 }
141 #endif /* CONFIG_CACHE_L2X0 */
142 
143 static const struct firmware_ops trusted_foundations_ops = {
144 	.set_cpu_boot_addr = tf_set_cpu_boot_addr,
145 	.prepare_idle = tf_prepare_idle,
146 #ifdef CONFIG_CACHE_L2X0
147 	.l2x0_init = tf_init_cache,
148 #endif
149 };
150 
151 void register_trusted_foundations(struct trusted_foundations_platform_data *pd)
152 {
153 	/*
154 	 * we are not using version information for now since currently
155 	 * supported SMCs are compatible with all TF releases
156 	 */
157 	register_firmware_ops(&trusted_foundations_ops);
158 }
159 
160 void of_register_trusted_foundations(void)
161 {
162 	struct device_node *node;
163 	struct trusted_foundations_platform_data pdata;
164 	int err;
165 
166 	node = of_find_compatible_node(NULL, NULL, "tlm,trusted-foundations");
167 	if (!node)
168 		return;
169 
170 	err = of_property_read_u32(node, "tlm,version-major",
171 				   &pdata.version_major);
172 	if (err != 0)
173 		panic("Trusted Foundation: missing version-major property\n");
174 	err = of_property_read_u32(node, "tlm,version-minor",
175 				   &pdata.version_minor);
176 	if (err != 0)
177 		panic("Trusted Foundation: missing version-minor property\n");
178 	register_trusted_foundations(&pdata);
179 }
180 
181 bool trusted_foundations_registered(void)
182 {
183 	return firmware_ops == &trusted_foundations_ops;
184 }
185