xref: /openbmc/u-boot/arch/arm/lib/psci-dt.c (revision 2d2811c2)
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 	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)
69 	psci_ver = ARM_PSCI_VER_1_0;
70 #endif
71 	switch (psci_ver) {
72 	case ARM_PSCI_VER_1_0:
73 		tmp = fdt_setprop_string(fdt, nodeoff,
74 				"compatible", "arm,psci-1.0");
75 		if (tmp)
76 			return tmp;
77 	case ARM_PSCI_VER_0_2:
78 		tmp = fdt_appendprop_string(fdt, nodeoff,
79 				"compatible", "arm,psci-0.2");
80 		if (tmp)
81 			return tmp;
82 	default:
83 	/*
84 	 * The Secure firmware framework isn't able to support PSCI version 0.1.
85 	 */
86 #ifndef CONFIG_ARMV8_SEC_FIRMWARE_SUPPORT
87 		tmp = fdt_appendprop_string(fdt, nodeoff,
88 				"compatible", "arm,psci");
89 		if (tmp)
90 			return tmp;
91 		tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_suspend",
92 				ARM_PSCI_FN_CPU_SUSPEND);
93 		if (tmp)
94 			return tmp;
95 		tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_off",
96 				ARM_PSCI_FN_CPU_OFF);
97 		if (tmp)
98 			return tmp;
99 		tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_on",
100 				ARM_PSCI_FN_CPU_ON);
101 		if (tmp)
102 			return tmp;
103 		tmp = fdt_setprop_u32(fdt, nodeoff, "migrate",
104 				ARM_PSCI_FN_MIGRATE);
105 		if (tmp)
106 			return tmp;
107 #endif
108 		break;
109 	}
110 
111 	tmp = fdt_setprop_string(fdt, nodeoff, "method", "smc");
112 	if (tmp)
113 		return tmp;
114 
115 #endif
116 	return 0;
117 }
118