2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License version 2 as
4 * published by the Free Software Foundation.
6 * This program is distributed in the hope that it will be useful,
7 * but WITHOUT ANY WARRANTY; without even the implied warranty of
8 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
9 * GNU General Public License for more details.
11 * Copyright (C) 2015 ARM Limited
14 #define pr_fmt(fmt) "psci: " fmt
16 #include <linux/errno.h>
17 #include <linux/linkage.h>
20 #include <linux/printk.h>
21 #include <linux/psci.h>
22 #include <linux/reboot.h>
24 #include <uapi/linux/psci.h>
26 #include <asm/cputype.h>
27 #include <asm/system_misc.h>
28 #include <asm/smp_plat.h>
31 * While a 64-bit OS can make calls with SMC32 calling conventions, for some
32 * calls it is necessary to use SMC64 to pass or return 64-bit values. For such
33 * calls PSCI_0_2_FN_NATIVE(x) will choose the appropriate (native-width)
37 #define PSCI_0_2_FN_NATIVE(name) PSCI_0_2_FN64_##name
39 #define PSCI_0_2_FN_NATIVE(name) PSCI_0_2_FN_##name
43 * The CPU any Trusted OS is resident on. The trusted OS may reject CPU_OFF
44 * calls to its resident CPU, so we must avoid issuing those. We never migrate
45 * a Trusted OS even if it claims to be capable of migration -- doing so will
46 * require cooperation with a Trusted OS driver.
48 static int resident_cpu = -1;
50 bool psci_tos_resident_on(int cpu)
52 return cpu == resident_cpu;
55 struct psci_operations psci_ops;
57 typedef unsigned long (psci_fn)(unsigned long, unsigned long,
58 unsigned long, unsigned long);
59 asmlinkage psci_fn __invoke_psci_fn_hvc;
60 asmlinkage psci_fn __invoke_psci_fn_smc;
61 static psci_fn *invoke_psci_fn;
71 static u32 psci_function_id[PSCI_FN_MAX];
73 #define PSCI_0_2_POWER_STATE_MASK \
74 (PSCI_0_2_POWER_STATE_ID_MASK | \
75 PSCI_0_2_POWER_STATE_TYPE_MASK | \
76 PSCI_0_2_POWER_STATE_AFFL_MASK)
78 #define PSCI_1_0_EXT_POWER_STATE_MASK \
79 (PSCI_1_0_EXT_POWER_STATE_ID_MASK | \
80 PSCI_1_0_EXT_POWER_STATE_TYPE_MASK)
82 static u32 psci_cpu_suspend_feature;
84 static inline bool psci_has_ext_power_state(void)
86 return psci_cpu_suspend_feature &
87 PSCI_1_0_FEATURES_CPU_SUSPEND_PF_MASK;
90 bool psci_power_state_loses_context(u32 state)
92 const u32 mask = psci_has_ext_power_state() ?
93 PSCI_1_0_EXT_POWER_STATE_TYPE_MASK :
94 PSCI_0_2_POWER_STATE_TYPE_MASK;
99 bool psci_power_state_is_valid(u32 state)
101 const u32 valid_mask = psci_has_ext_power_state() ?
102 PSCI_1_0_EXT_POWER_STATE_MASK :
103 PSCI_0_2_POWER_STATE_MASK;
105 return !(state & ~valid_mask);
108 static int psci_to_linux_errno(int errno)
111 case PSCI_RET_SUCCESS:
113 case PSCI_RET_NOT_SUPPORTED:
115 case PSCI_RET_INVALID_PARAMS:
116 case PSCI_RET_INVALID_ADDRESS:
118 case PSCI_RET_DENIED:
125 static u32 psci_get_version(void)
127 return invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
130 static int psci_cpu_suspend(u32 state, unsigned long entry_point)
135 fn = psci_function_id[PSCI_FN_CPU_SUSPEND];
136 err = invoke_psci_fn(fn, state, entry_point, 0);
137 return psci_to_linux_errno(err);
140 static int psci_cpu_off(u32 state)
145 fn = psci_function_id[PSCI_FN_CPU_OFF];
146 err = invoke_psci_fn(fn, state, 0, 0);
147 return psci_to_linux_errno(err);
150 static int psci_cpu_on(unsigned long cpuid, unsigned long entry_point)
155 fn = psci_function_id[PSCI_FN_CPU_ON];
156 err = invoke_psci_fn(fn, cpuid, entry_point, 0);
157 return psci_to_linux_errno(err);
160 static int psci_migrate(unsigned long cpuid)
165 fn = psci_function_id[PSCI_FN_MIGRATE];
166 err = invoke_psci_fn(fn, cpuid, 0, 0);
167 return psci_to_linux_errno(err);
170 static int psci_affinity_info(unsigned long target_affinity,
171 unsigned long lowest_affinity_level)
173 return invoke_psci_fn(PSCI_0_2_FN_NATIVE(AFFINITY_INFO),
174 target_affinity, lowest_affinity_level, 0);
177 static int psci_migrate_info_type(void)
179 return invoke_psci_fn(PSCI_0_2_FN_MIGRATE_INFO_TYPE, 0, 0, 0);
182 static unsigned long psci_migrate_info_up_cpu(void)
184 return invoke_psci_fn(PSCI_0_2_FN_NATIVE(MIGRATE_INFO_UP_CPU),
188 static int get_set_conduit_method(struct device_node *np)
192 pr_info("probing for conduit method from DT.\n");
194 if (of_property_read_string(np, "method", &method)) {
195 pr_warn("missing \"method\" property\n");
199 if (!strcmp("hvc", method)) {
200 invoke_psci_fn = __invoke_psci_fn_hvc;
201 } else if (!strcmp("smc", method)) {
202 invoke_psci_fn = __invoke_psci_fn_smc;
204 pr_warn("invalid \"method\" property: %s\n", method);
210 static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
212 invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
215 static void psci_sys_poweroff(void)
217 invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
220 static int __init psci_features(u32 psci_func_id)
222 return invoke_psci_fn(PSCI_1_0_FN_PSCI_FEATURES,
226 static void __init psci_init_cpu_suspend(void)
228 int feature = psci_features(psci_function_id[PSCI_FN_CPU_SUSPEND]);
230 if (feature != PSCI_RET_NOT_SUPPORTED)
231 psci_cpu_suspend_feature = feature;
235 * Detect the presence of a resident Trusted OS which may cause CPU_OFF to
236 * return DENIED (which would be fatal).
238 static void __init psci_init_migrate(void)
243 type = psci_ops.migrate_info_type();
245 if (type == PSCI_0_2_TOS_MP) {
246 pr_info("Trusted OS migration not required\n");
250 if (type == PSCI_RET_NOT_SUPPORTED) {
251 pr_info("MIGRATE_INFO_TYPE not supported.\n");
255 if (type != PSCI_0_2_TOS_UP_MIGRATE &&
256 type != PSCI_0_2_TOS_UP_NO_MIGRATE) {
257 pr_err("MIGRATE_INFO_TYPE returned unknown type (%d)\n", type);
261 cpuid = psci_migrate_info_up_cpu();
262 if (cpuid & ~MPIDR_HWID_BITMASK) {
263 pr_warn("MIGRATE_INFO_UP_CPU reported invalid physical ID (0x%lx)\n",
268 cpu = get_logical_index(cpuid);
269 resident_cpu = cpu >= 0 ? cpu : -1;
271 pr_info("Trusted OS resident on physical CPU 0x%lx\n", cpuid);
274 static void __init psci_0_2_set_functions(void)
276 pr_info("Using standard PSCI v0.2 function IDs\n");
277 psci_function_id[PSCI_FN_CPU_SUSPEND] = PSCI_0_2_FN_NATIVE(CPU_SUSPEND);
278 psci_ops.cpu_suspend = psci_cpu_suspend;
280 psci_function_id[PSCI_FN_CPU_OFF] = PSCI_0_2_FN_CPU_OFF;
281 psci_ops.cpu_off = psci_cpu_off;
283 psci_function_id[PSCI_FN_CPU_ON] = PSCI_0_2_FN_NATIVE(CPU_ON);
284 psci_ops.cpu_on = psci_cpu_on;
286 psci_function_id[PSCI_FN_MIGRATE] = PSCI_0_2_FN_NATIVE(MIGRATE);
287 psci_ops.migrate = psci_migrate;
289 psci_ops.affinity_info = psci_affinity_info;
291 psci_ops.migrate_info_type = psci_migrate_info_type;
293 arm_pm_restart = psci_sys_reset;
295 pm_power_off = psci_sys_poweroff;
299 * Probe function for PSCI firmware versions >= 0.2
301 static int __init psci_probe(void)
303 u32 ver = psci_get_version();
305 pr_info("PSCIv%d.%d detected in firmware.\n",
306 PSCI_VERSION_MAJOR(ver),
307 PSCI_VERSION_MINOR(ver));
309 if (PSCI_VERSION_MAJOR(ver) == 0 && PSCI_VERSION_MINOR(ver) < 2) {
310 pr_err("Conflicting PSCI version detected.\n");
314 psci_0_2_set_functions();
318 psci_init_cpu_suspend();
323 typedef int (*psci_initcall_t)(const struct device_node *);
326 * PSCI init function for PSCI versions >=0.2
328 * Probe based on PSCI PSCI_VERSION function
330 static int __init psci_0_2_init(struct device_node *np)
334 err = get_set_conduit_method(np);
339 * Starting with v0.2, the PSCI specification introduced a call
340 * (PSCI_VERSION) that allows probing the firmware version, so
341 * that PSCI function IDs and version specific initialization
342 * can be carried out according to the specific version reported
353 * PSCI < v0.2 get PSCI Function IDs via DT.
355 static int __init psci_0_1_init(struct device_node *np)
360 err = get_set_conduit_method(np);
365 pr_info("Using PSCI v0.1 Function IDs from DT\n");
367 if (!of_property_read_u32(np, "cpu_suspend", &id)) {
368 psci_function_id[PSCI_FN_CPU_SUSPEND] = id;
369 psci_ops.cpu_suspend = psci_cpu_suspend;
372 if (!of_property_read_u32(np, "cpu_off", &id)) {
373 psci_function_id[PSCI_FN_CPU_OFF] = id;
374 psci_ops.cpu_off = psci_cpu_off;
377 if (!of_property_read_u32(np, "cpu_on", &id)) {
378 psci_function_id[PSCI_FN_CPU_ON] = id;
379 psci_ops.cpu_on = psci_cpu_on;
382 if (!of_property_read_u32(np, "migrate", &id)) {
383 psci_function_id[PSCI_FN_MIGRATE] = id;
384 psci_ops.migrate = psci_migrate;
392 static const struct of_device_id const psci_of_match[] __initconst = {
393 { .compatible = "arm,psci", .data = psci_0_1_init},
394 { .compatible = "arm,psci-0.2", .data = psci_0_2_init},
398 int __init psci_dt_init(void)
400 struct device_node *np;
401 const struct of_device_id *matched_np;
402 psci_initcall_t init_fn;
404 np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np);
409 init_fn = (psci_initcall_t)matched_np->data;
415 * We use PSCI 0.2+ when ACPI is deployed on ARM64 and it's
416 * explicitly clarified in SBBR
418 int __init psci_acpi_init(void)
420 if (!acpi_psci_present()) {
421 pr_info("is not implemented in ACPI.\n");
425 pr_info("probing for conduit method from ACPI.\n");
427 if (acpi_psci_use_hvc())
428 invoke_psci_fn = __invoke_psci_fn_hvc;
430 invoke_psci_fn = __invoke_psci_fn_smc;