xref: /openbmc/u-boot/arch/arm/lib/psci-dt.c (revision 473af36a)
1 /*
2  * Copyright 2016 NXP Semiconductor, Inc.
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #include <common.h>
8 #include <libfdt.h>
9 #include <fdt_support.h>
10 #include <linux/sizes.h>
11 #include <linux/kernel.h>
12 #include <asm/psci.h>
13 #ifdef CONFIG_ARMV8_SEC_FIRMWARE_SUPPORT
14 #include <asm/armv8/sec_firmware.h>
15 #endif
16 
17 int fdt_psci(void *fdt)
18 {
19 #if defined(CONFIG_ARMV8_PSCI) || defined(CONFIG_ARMV7_PSCI)
20 	int nodeoff;
21 	unsigned int psci_ver = 0;
22 	char *psci_compt;
23 	int tmp;
24 
25 	nodeoff = fdt_path_offset(fdt, "/cpus");
26 	if (nodeoff < 0) {
27 		printf("couldn't find /cpus\n");
28 		return nodeoff;
29 	}
30 
31 	/* add 'enable-method = "psci"' to each cpu node */
32 	for (tmp = fdt_first_subnode(fdt, nodeoff);
33 	     tmp >= 0;
34 	     tmp = fdt_next_subnode(fdt, tmp)) {
35 		const struct fdt_property *prop;
36 		int len;
37 
38 		prop = fdt_get_property(fdt, tmp, "device_type", &len);
39 		if (!prop)
40 			continue;
41 		if (len < 4)
42 			continue;
43 		if (strcmp(prop->data, "cpu"))
44 			continue;
45 
46 		/*
47 		 * Not checking rv here, our approach is to skip over errors in
48 		 * individual cpu nodes, hopefully some of the nodes are
49 		 * processed correctly and those will boot
50 		 */
51 		fdt_setprop_string(fdt, tmp, "enable-method", "psci");
52 	}
53 
54 	/*
55 	 * The PSCI node might be called "/psci" or might be called something
56 	 * else but contain either of the compatible strings
57 	 * "arm,psci"/"arm,psci-0.2"
58 	 */
59 	nodeoff = fdt_path_offset(fdt, "/psci");
60 	if (nodeoff >= 0)
61 		goto init_psci_node;
62 
63 	nodeoff = fdt_node_offset_by_compatible(fdt, -1, "arm,psci");
64 	if (nodeoff >= 0)
65 		goto init_psci_node;
66 
67 	nodeoff = fdt_node_offset_by_compatible(fdt, -1, "arm,psci-0.2");
68 	if (nodeoff >= 0)
69 		goto init_psci_node;
70 
71 	nodeoff = fdt_node_offset_by_compatible(fdt, -1, "arm,psci-1.0");
72 	if (nodeoff >= 0)
73 		goto init_psci_node;
74 
75 	nodeoff = fdt_path_offset(fdt, "/");
76 	if (nodeoff < 0)
77 		return nodeoff;
78 
79 	nodeoff = fdt_add_subnode(fdt, nodeoff, "psci");
80 	if (nodeoff < 0)
81 		return nodeoff;
82 
83 init_psci_node:
84 #ifdef CONFIG_ARMV8_SEC_FIRMWARE_SUPPORT
85 	psci_ver = sec_firmware_support_psci_version();
86 #endif
87 	switch (psci_ver) {
88 	case 0x00010000:
89 		psci_compt = "arm,psci-1.0";
90 		break;
91 	case 0x00000002:
92 		psci_compt = "arm,psci-0.2";
93 		break;
94 	default:
95 		psci_compt = "arm,psci";
96 		break;
97 	}
98 
99 	tmp = fdt_setprop_string(fdt, nodeoff, "compatible", psci_compt);
100 	if (tmp)
101 		return tmp;
102 	tmp = fdt_setprop_string(fdt, nodeoff, "method", "smc");
103 	if (tmp)
104 		return tmp;
105 
106 #ifdef CONFIG_ARMV7_PSCI
107 	tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_suspend",
108 				ARM_PSCI_FN_CPU_SUSPEND);
109 	if (tmp)
110 		return tmp;
111 	tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_off", ARM_PSCI_FN_CPU_OFF);
112 	if (tmp)
113 		return tmp;
114 	tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_on", ARM_PSCI_FN_CPU_ON);
115 	if (tmp)
116 		return tmp;
117 	tmp = fdt_setprop_u32(fdt, nodeoff, "migrate", ARM_PSCI_FN_MIGRATE);
118 	if (tmp)
119 		return tmp;
120 #endif
121 #endif
122 	return 0;
123 }
124