1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2017 Masahiro Yamada <yamada.masahiro@socionext.com>
4 *
5 * Based on drivers/firmware/psci.c from Linux:
6 * Copyright (C) 2015 ARM Limited
7 */
8
9 #include <common.h>
10 #include <command.h>
11 #include <dm.h>
12 #include <irq_func.h>
13 #include <log.h>
14 #include <dm/lists.h>
15 #include <efi_loader.h>
16 #include <linux/delay.h>
17 #include <linux/libfdt.h>
18 #include <linux/arm-smccc.h>
19 #include <linux/errno.h>
20 #include <linux/printk.h>
21 #include <linux/psci.h>
22 #include <asm/system.h>
23
24 #define DRIVER_NAME "psci"
25
26 #define PSCI_METHOD_HVC 1
27 #define PSCI_METHOD_SMC 2
28
29 #if CONFIG_IS_ENABLED(EFI_LOADER)
30 int __efi_runtime_data psci_method;
31 #else
32 int psci_method __attribute__ ((section(".data")));
33 #endif
34
invoke_psci_fn(unsigned long function_id,unsigned long arg0,unsigned long arg1,unsigned long arg2)35 unsigned long __efi_runtime invoke_psci_fn
36 (unsigned long function_id, unsigned long arg0,
37 unsigned long arg1, unsigned long arg2)
38 {
39 struct arm_smccc_res res;
40
41 /*
42 * In the __efi_runtime we need to avoid the switch statement. In some
43 * cases the compiler creates lookup tables to implement switch. These
44 * tables are not correctly relocated when SetVirtualAddressMap is
45 * called.
46 */
47 if (psci_method == PSCI_METHOD_SMC)
48 arm_smccc_smc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);
49 else if (psci_method == PSCI_METHOD_HVC)
50 arm_smccc_hvc(function_id, arg0, arg1, arg2, 0, 0, 0, 0, &res);
51 else
52 res.a0 = PSCI_RET_DISABLED;
53 return res.a0;
54 }
55
psci_bind(struct udevice * dev)56 static int psci_bind(struct udevice *dev)
57 {
58 /* No SYSTEM_RESET support for PSCI 0.1 */
59 if (device_is_compatible(dev, "arm,psci-0.2") ||
60 device_is_compatible(dev, "arm,psci-1.0")) {
61 int ret;
62
63 /* bind psci-sysreset optionally */
64 ret = device_bind_driver(dev, "psci-sysreset", "psci-sysreset",
65 NULL);
66 if (ret)
67 pr_debug("PSCI System Reset was not bound.\n");
68 }
69
70 return 0;
71 }
72
psci_probe(struct udevice * dev)73 static int psci_probe(struct udevice *dev)
74 {
75 const char *method;
76
77 #if defined(CONFIG_ARM64)
78 if (current_el() == 3)
79 return -EINVAL;
80 #endif
81
82 method = ofnode_read_string(dev_ofnode(dev), "method");
83 if (!method) {
84 pr_warn("missing \"method\" property\n");
85 return -ENXIO;
86 }
87
88 if (!strcmp("hvc", method)) {
89 psci_method = PSCI_METHOD_HVC;
90 } else if (!strcmp("smc", method)) {
91 psci_method = PSCI_METHOD_SMC;
92 } else {
93 pr_warn("invalid \"method\" property: %s\n", method);
94 return -EINVAL;
95 }
96
97 return 0;
98 }
99
100 /**
101 * void do_psci_probe() - probe PSCI firmware driver
102 *
103 * Ensure that psci_method is initialized.
104 */
do_psci_probe(void)105 static void __maybe_unused do_psci_probe(void)
106 {
107 struct udevice *dev;
108
109 uclass_get_device_by_name(UCLASS_FIRMWARE, DRIVER_NAME, &dev);
110 }
111
112 #if IS_ENABLED(CONFIG_EFI_LOADER) && IS_ENABLED(CONFIG_PSCI_RESET)
efi_reset_system_init(void)113 efi_status_t efi_reset_system_init(void)
114 {
115 do_psci_probe();
116 return EFI_SUCCESS;
117 }
118
efi_reset_system(enum efi_reset_type reset_type,efi_status_t reset_status,unsigned long data_size,void * reset_data)119 void __efi_runtime EFIAPI efi_reset_system(enum efi_reset_type reset_type,
120 efi_status_t reset_status,
121 unsigned long data_size,
122 void *reset_data)
123 {
124 if (reset_type == EFI_RESET_COLD ||
125 reset_type == EFI_RESET_WARM ||
126 reset_type == EFI_RESET_PLATFORM_SPECIFIC) {
127 invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
128 } else if (reset_type == EFI_RESET_SHUTDOWN) {
129 invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
130 }
131 while (1)
132 ;
133 }
134 #endif /* IS_ENABLED(CONFIG_EFI_LOADER) && IS_ENABLED(CONFIG_PSCI_RESET) */
135
136 #ifdef CONFIG_PSCI_RESET
reset_misc(void)137 void reset_misc(void)
138 {
139 do_psci_probe();
140 invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
141 }
142 #endif /* CONFIG_PSCI_RESET */
143
144 #ifdef CONFIG_CMD_POWEROFF
do_poweroff(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])145 int do_poweroff(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
146 {
147 do_psci_probe();
148
149 puts("poweroff ...\n");
150 udelay(50000); /* wait 50 ms */
151
152 disable_interrupts();
153 invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
154 enable_interrupts();
155
156 log_err("Power off not supported on this platform\n");
157 return CMD_RET_FAILURE;
158 }
159 #endif
160
161 static const struct udevice_id psci_of_match[] = {
162 { .compatible = "arm,psci" },
163 { .compatible = "arm,psci-0.2" },
164 { .compatible = "arm,psci-1.0" },
165 {},
166 };
167
168 U_BOOT_DRIVER(psci) = {
169 .name = DRIVER_NAME,
170 .id = UCLASS_FIRMWARE,
171 .of_match = psci_of_match,
172 .bind = psci_bind,
173 .probe = psci_probe,
174 };
175