1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright 2016 NXP Semiconductor, Inc.
4 */
5
6 #include <common.h>
7 #include <linux/libfdt.h>
8 #include <fdt_support.h>
9 #include <linux/sizes.h>
10 #include <linux/kernel.h>
11 #include <asm/psci.h>
12 #ifdef CONFIG_ARMV8_SEC_FIRMWARE_SUPPORT
13 #include <asm/armv8/sec_firmware.h>
14 #endif
15
fdt_psci(void * fdt)16 int fdt_psci(void *fdt)
17 {
18 #if defined(CONFIG_ARMV7_PSCI) || defined(CONFIG_ARMV8_PSCI) || \
19 defined(CONFIG_SEC_FIRMWARE_ARMV8_PSCI)
20 int nodeoff;
21 unsigned int psci_ver = 0;
22 int tmp;
23
24 nodeoff = fdt_path_offset(fdt, "/cpus");
25 if (nodeoff < 0) {
26 printf("couldn't find /cpus\n");
27 return nodeoff;
28 }
29
30 /* add 'enable-method = "psci"' to each cpu node */
31 for (tmp = fdt_first_subnode(fdt, nodeoff);
32 tmp >= 0;
33 tmp = fdt_next_subnode(fdt, tmp)) {
34 const struct fdt_property *prop;
35 int len;
36
37 prop = fdt_get_property(fdt, tmp, "device_type", &len);
38 if (!prop)
39 continue;
40 if (len < 4)
41 continue;
42 if (strcmp(prop->data, "cpu"))
43 continue;
44
45 /*
46 * Not checking rv here, our approach is to skip over errors in
47 * individual cpu nodes, hopefully some of the nodes are
48 * processed correctly and those will boot
49 */
50 fdt_setprop_string(fdt, tmp, "enable-method", "psci");
51 }
52
53 nodeoff = fdt_path_offset(fdt, "/psci");
54 if (nodeoff >= 0)
55 goto init_psci_node;
56
57 nodeoff = fdt_path_offset(fdt, "/");
58 if (nodeoff < 0)
59 return nodeoff;
60
61 nodeoff = fdt_add_subnode(fdt, nodeoff, "psci");
62 if (nodeoff < 0)
63 return nodeoff;
64
65 init_psci_node:
66 #ifdef CONFIG_ARMV8_SEC_FIRMWARE_SUPPORT
67 psci_ver = sec_firmware_support_psci_version();
68 #elif defined(CONFIG_ARMV7_PSCI_1_0) || defined(CONFIG_ARMV8_PSCI)
69 psci_ver = ARM_PSCI_VER_1_0;
70 #elif defined(CONFIG_ARMV7_PSCI_0_2)
71 psci_ver = ARM_PSCI_VER_0_2;
72 #endif
73 if (psci_ver >= ARM_PSCI_VER_1_0) {
74 tmp = fdt_setprop_string(fdt, nodeoff,
75 "compatible", "arm,psci-1.0");
76 if (tmp)
77 return tmp;
78 }
79
80 if (psci_ver >= ARM_PSCI_VER_0_2) {
81 tmp = fdt_appendprop_string(fdt, nodeoff,
82 "compatible", "arm,psci-0.2");
83 if (tmp)
84 return tmp;
85 }
86
87 #ifndef CONFIG_ARMV8_SEC_FIRMWARE_SUPPORT
88 /*
89 * The Secure firmware framework isn't able to support PSCI version 0.1.
90 */
91 if (psci_ver < ARM_PSCI_VER_0_2) {
92 tmp = fdt_appendprop_string(fdt, nodeoff,
93 "compatible", "arm,psci");
94 if (tmp)
95 return tmp;
96 tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_suspend",
97 ARM_PSCI_FN_CPU_SUSPEND);
98 if (tmp)
99 return tmp;
100 tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_off",
101 ARM_PSCI_FN_CPU_OFF);
102 if (tmp)
103 return tmp;
104 tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_on",
105 ARM_PSCI_FN_CPU_ON);
106 if (tmp)
107 return tmp;
108 tmp = fdt_setprop_u32(fdt, nodeoff, "migrate",
109 ARM_PSCI_FN_MIGRATE);
110 if (tmp)
111 return tmp;
112 }
113 #endif
114
115 tmp = fdt_setprop_string(fdt, nodeoff, "method", "smc");
116 if (tmp)
117 return tmp;
118
119 tmp = fdt_setprop_string(fdt, nodeoff, "status", "okay");
120 if (tmp)
121 return tmp;
122
123 #endif
124 return 0;
125 }
126