xref: /openbmc/u-boot/arch/arm/lib/psci-dt.c (revision 9d466f2f)
1 /*
2  * Copyright 2016 NXP Semiconductor, Inc.
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #include <common.h>
8 #include <linux/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_ARMV7_PSCI) || defined(CONFIG_ARMV8_PSCI) || \
20 	defined(CONFIG_SEC_FIRMWARE_ARMV8_PSCI)
21 	int nodeoff;
22 	unsigned int psci_ver = 0;
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 	nodeoff = fdt_path_offset(fdt, "/psci");
55 	if (nodeoff >= 0)
56 		goto init_psci_node;
57 
58 	nodeoff = fdt_path_offset(fdt, "/");
59 	if (nodeoff < 0)
60 		return nodeoff;
61 
62 	nodeoff = fdt_add_subnode(fdt, nodeoff, "psci");
63 	if (nodeoff < 0)
64 		return nodeoff;
65 
66 init_psci_node:
67 #ifdef CONFIG_ARMV8_SEC_FIRMWARE_SUPPORT
68 	psci_ver = sec_firmware_support_psci_version();
69 #elif defined(CONFIG_ARMV7_PSCI_1_0) || defined(CONFIG_ARMV8_PSCI)
70 	psci_ver = ARM_PSCI_VER_1_0;
71 #endif
72 	if (psci_ver >= 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 	}
78 
79 	if (psci_ver >= ARM_PSCI_VER_0_2) {
80 		tmp = fdt_appendprop_string(fdt, nodeoff,
81 				"compatible", "arm,psci-0.2");
82 		if (tmp)
83 			return tmp;
84 	}
85 
86 #ifndef CONFIG_ARMV8_SEC_FIRMWARE_SUPPORT
87 	/*
88 	 * The Secure firmware framework isn't able to support PSCI version 0.1.
89 	 */
90 	if (psci_ver < ARM_PSCI_VER_0_2) {
91 		tmp = fdt_appendprop_string(fdt, nodeoff,
92 				"compatible", "arm,psci");
93 		if (tmp)
94 			return tmp;
95 		tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_suspend",
96 				ARM_PSCI_FN_CPU_SUSPEND);
97 		if (tmp)
98 			return tmp;
99 		tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_off",
100 				ARM_PSCI_FN_CPU_OFF);
101 		if (tmp)
102 			return tmp;
103 		tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_on",
104 				ARM_PSCI_FN_CPU_ON);
105 		if (tmp)
106 			return tmp;
107 		tmp = fdt_setprop_u32(fdt, nodeoff, "migrate",
108 				ARM_PSCI_FN_MIGRATE);
109 		if (tmp)
110 			return tmp;
111 	}
112 #endif
113 
114 	tmp = fdt_setprop_string(fdt, nodeoff, "method", "smc");
115 	if (tmp)
116 		return tmp;
117 
118 #endif
119 	return 0;
120 }
121