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) 2013 ARM Limited
13 * Author: Will Deacon <will.deacon@arm.com>
16 #define pr_fmt(fmt) "psci: " fmt
18 #include <linux/acpi.h>
19 #include <linux/init.h>
21 #include <linux/smp.h>
22 #include <linux/reboot.h>
24 #include <linux/delay.h>
25 #include <linux/slab.h>
26 #include <uapi/linux/psci.h>
29 #include <asm/compiler.h>
30 #include <asm/cpu_ops.h>
31 #include <asm/errno.h>
33 #include <asm/smp_plat.h>
34 #include <asm/suspend.h>
35 #include <asm/system_misc.h>
37 #define PSCI_POWER_STATE_TYPE_STANDBY 0
38 #define PSCI_POWER_STATE_TYPE_POWER_DOWN 1
40 struct psci_power_state {
46 struct psci_operations {
47 int (*cpu_suspend)(struct psci_power_state state,
48 unsigned long entry_point);
49 int (*cpu_off)(struct psci_power_state state);
50 int (*cpu_on)(unsigned long cpuid, unsigned long entry_point);
51 int (*migrate)(unsigned long cpuid);
52 int (*affinity_info)(unsigned long target_affinity,
53 unsigned long lowest_affinity_level);
54 int (*migrate_info_type)(void);
57 static struct psci_operations psci_ops;
59 static int (*invoke_psci_fn)(u64, u64, u64, u64);
60 typedef int (*psci_initcall_t)(const struct device_node *);
62 asmlinkage int __invoke_psci_fn_hvc(u64, u64, u64, u64);
63 asmlinkage int __invoke_psci_fn_smc(u64, u64, u64, u64);
70 PSCI_FN_AFFINITY_INFO,
71 PSCI_FN_MIGRATE_INFO_TYPE,
75 static DEFINE_PER_CPU_READ_MOSTLY(struct psci_power_state *, psci_power_state);
77 static u32 psci_function_id[PSCI_FN_MAX];
79 static int psci_to_linux_errno(int errno)
82 case PSCI_RET_SUCCESS:
84 case PSCI_RET_NOT_SUPPORTED:
86 case PSCI_RET_INVALID_PARAMS:
95 static u32 psci_power_state_pack(struct psci_power_state state)
97 return ((state.id << PSCI_0_2_POWER_STATE_ID_SHIFT)
98 & PSCI_0_2_POWER_STATE_ID_MASK) |
99 ((state.type << PSCI_0_2_POWER_STATE_TYPE_SHIFT)
100 & PSCI_0_2_POWER_STATE_TYPE_MASK) |
101 ((state.affinity_level << PSCI_0_2_POWER_STATE_AFFL_SHIFT)
102 & PSCI_0_2_POWER_STATE_AFFL_MASK);
105 static void psci_power_state_unpack(u32 power_state,
106 struct psci_power_state *state)
108 state->id = (power_state & PSCI_0_2_POWER_STATE_ID_MASK) >>
109 PSCI_0_2_POWER_STATE_ID_SHIFT;
110 state->type = (power_state & PSCI_0_2_POWER_STATE_TYPE_MASK) >>
111 PSCI_0_2_POWER_STATE_TYPE_SHIFT;
112 state->affinity_level =
113 (power_state & PSCI_0_2_POWER_STATE_AFFL_MASK) >>
114 PSCI_0_2_POWER_STATE_AFFL_SHIFT;
117 static int psci_get_version(void)
121 err = invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
125 static int psci_cpu_suspend(struct psci_power_state state,
126 unsigned long entry_point)
131 fn = psci_function_id[PSCI_FN_CPU_SUSPEND];
132 power_state = psci_power_state_pack(state);
133 err = invoke_psci_fn(fn, power_state, entry_point, 0);
134 return psci_to_linux_errno(err);
137 static int psci_cpu_off(struct psci_power_state state)
142 fn = psci_function_id[PSCI_FN_CPU_OFF];
143 power_state = psci_power_state_pack(state);
144 err = invoke_psci_fn(fn, power_state, 0, 0);
145 return psci_to_linux_errno(err);
148 static int psci_cpu_on(unsigned long cpuid, unsigned long entry_point)
153 fn = psci_function_id[PSCI_FN_CPU_ON];
154 err = invoke_psci_fn(fn, cpuid, entry_point, 0);
155 return psci_to_linux_errno(err);
158 static int psci_migrate(unsigned long cpuid)
163 fn = psci_function_id[PSCI_FN_MIGRATE];
164 err = invoke_psci_fn(fn, cpuid, 0, 0);
165 return psci_to_linux_errno(err);
168 static int psci_affinity_info(unsigned long target_affinity,
169 unsigned long lowest_affinity_level)
174 fn = psci_function_id[PSCI_FN_AFFINITY_INFO];
175 err = invoke_psci_fn(fn, target_affinity, lowest_affinity_level, 0);
179 static int psci_migrate_info_type(void)
184 fn = psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE];
185 err = invoke_psci_fn(fn, 0, 0, 0);
189 static int __maybe_unused cpu_psci_cpu_init_idle(struct device_node *cpu_node,
192 int i, ret, count = 0;
193 struct psci_power_state *psci_states;
194 struct device_node *state_node;
197 * If the PSCI cpu_suspend function hook has not been initialized
198 * idle states must not be enabled, so bail out
200 if (!psci_ops.cpu_suspend)
203 /* Count idle states */
204 while ((state_node = of_parse_phandle(cpu_node, "cpu-idle-states",
207 of_node_put(state_node);
213 psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL);
217 for (i = 0; i < count; i++) {
218 u32 psci_power_state;
220 state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i);
222 ret = of_property_read_u32(state_node,
223 "arm,psci-suspend-param",
226 pr_warn(" * %s missing arm,psci-suspend-param property\n",
227 state_node->full_name);
228 of_node_put(state_node);
232 of_node_put(state_node);
233 pr_debug("psci-power-state %#x index %d\n", psci_power_state,
235 psci_power_state_unpack(psci_power_state, &psci_states[i]);
237 /* Idle states parsed correctly, initialize per-cpu pointer */
238 per_cpu(psci_power_state, cpu) = psci_states;
246 static int get_set_conduit_method(struct device_node *np)
250 pr_info("probing for conduit method from DT.\n");
252 if (of_property_read_string(np, "method", &method)) {
253 pr_warn("missing \"method\" property\n");
257 if (!strcmp("hvc", method)) {
258 invoke_psci_fn = __invoke_psci_fn_hvc;
259 } else if (!strcmp("smc", method)) {
260 invoke_psci_fn = __invoke_psci_fn_smc;
262 pr_warn("invalid \"method\" property: %s\n", method);
268 static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
270 invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
273 static void psci_sys_poweroff(void)
275 invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
278 static void __init psci_0_2_set_functions(void)
280 pr_info("Using standard PSCI v0.2 function IDs\n");
281 psci_function_id[PSCI_FN_CPU_SUSPEND] = PSCI_0_2_FN64_CPU_SUSPEND;
282 psci_ops.cpu_suspend = psci_cpu_suspend;
284 psci_function_id[PSCI_FN_CPU_OFF] = PSCI_0_2_FN_CPU_OFF;
285 psci_ops.cpu_off = psci_cpu_off;
287 psci_function_id[PSCI_FN_CPU_ON] = PSCI_0_2_FN64_CPU_ON;
288 psci_ops.cpu_on = psci_cpu_on;
290 psci_function_id[PSCI_FN_MIGRATE] = PSCI_0_2_FN64_MIGRATE;
291 psci_ops.migrate = psci_migrate;
293 psci_function_id[PSCI_FN_AFFINITY_INFO] = PSCI_0_2_FN64_AFFINITY_INFO;
294 psci_ops.affinity_info = psci_affinity_info;
296 psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE] =
297 PSCI_0_2_FN_MIGRATE_INFO_TYPE;
298 psci_ops.migrate_info_type = psci_migrate_info_type;
300 arm_pm_restart = psci_sys_reset;
302 pm_power_off = psci_sys_poweroff;
306 * Probe function for PSCI firmware versions >= 0.2
308 static int __init psci_probe(void)
310 int ver = psci_get_version();
312 if (ver == PSCI_RET_NOT_SUPPORTED) {
314 * PSCI versions >=0.2 mandates implementation of
317 pr_err("PSCI firmware does not comply with the v0.2 spec.\n");
320 pr_info("PSCIv%d.%d detected in firmware.\n",
321 PSCI_VERSION_MAJOR(ver),
322 PSCI_VERSION_MINOR(ver));
324 if (PSCI_VERSION_MAJOR(ver) == 0 &&
325 PSCI_VERSION_MINOR(ver) < 2) {
326 pr_err("Conflicting PSCI version detected.\n");
331 psci_0_2_set_functions();
337 * PSCI init function for PSCI versions >=0.2
339 * Probe based on PSCI PSCI_VERSION function
341 static int __init psci_0_2_init(struct device_node *np)
345 err = get_set_conduit_method(np);
350 * Starting with v0.2, the PSCI specification introduced a call
351 * (PSCI_VERSION) that allows probing the firmware version, so
352 * that PSCI function IDs and version specific initialization
353 * can be carried out according to the specific version reported
364 * PSCI < v0.2 get PSCI Function IDs via DT.
366 static int __init psci_0_1_init(struct device_node *np)
371 err = get_set_conduit_method(np);
376 pr_info("Using PSCI v0.1 Function IDs from DT\n");
378 if (!of_property_read_u32(np, "cpu_suspend", &id)) {
379 psci_function_id[PSCI_FN_CPU_SUSPEND] = id;
380 psci_ops.cpu_suspend = psci_cpu_suspend;
383 if (!of_property_read_u32(np, "cpu_off", &id)) {
384 psci_function_id[PSCI_FN_CPU_OFF] = id;
385 psci_ops.cpu_off = psci_cpu_off;
388 if (!of_property_read_u32(np, "cpu_on", &id)) {
389 psci_function_id[PSCI_FN_CPU_ON] = id;
390 psci_ops.cpu_on = psci_cpu_on;
393 if (!of_property_read_u32(np, "migrate", &id)) {
394 psci_function_id[PSCI_FN_MIGRATE] = id;
395 psci_ops.migrate = psci_migrate;
403 static const struct of_device_id psci_of_match[] __initconst = {
404 { .compatible = "arm,psci", .data = psci_0_1_init},
405 { .compatible = "arm,psci-0.2", .data = psci_0_2_init},
409 int __init psci_dt_init(void)
411 struct device_node *np;
412 const struct of_device_id *matched_np;
413 psci_initcall_t init_fn;
415 np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np);
420 init_fn = (psci_initcall_t)matched_np->data;
425 * We use PSCI 0.2+ when ACPI is deployed on ARM64 and it's
426 * explicitly clarified in SBBR
428 int __init psci_acpi_init(void)
430 if (!acpi_psci_present()) {
431 pr_info("is not implemented in ACPI.\n");
435 pr_info("probing for conduit method from ACPI.\n");
437 if (acpi_psci_use_hvc())
438 invoke_psci_fn = __invoke_psci_fn_hvc;
440 invoke_psci_fn = __invoke_psci_fn_smc;
447 static int __init cpu_psci_cpu_init(struct device_node *dn, unsigned int cpu)
452 static int __init cpu_psci_cpu_prepare(unsigned int cpu)
454 if (!psci_ops.cpu_on) {
455 pr_err("no cpu_on method, not booting CPU%d\n", cpu);
462 static int cpu_psci_cpu_boot(unsigned int cpu)
464 int err = psci_ops.cpu_on(cpu_logical_map(cpu), __pa(secondary_entry));
466 pr_err("failed to boot CPU%d (%d)\n", cpu, err);
471 #ifdef CONFIG_HOTPLUG_CPU
472 static int cpu_psci_cpu_disable(unsigned int cpu)
474 /* Fail early if we don't have CPU_OFF support */
475 if (!psci_ops.cpu_off)
480 static void cpu_psci_cpu_die(unsigned int cpu)
484 * There are no known implementations of PSCI actually using the
485 * power state field, pass a sensible default for now.
487 struct psci_power_state state = {
488 .type = PSCI_POWER_STATE_TYPE_POWER_DOWN,
491 ret = psci_ops.cpu_off(state);
493 pr_crit("unable to power off CPU%u (%d)\n", cpu, ret);
496 static int cpu_psci_cpu_kill(unsigned int cpu)
500 if (!psci_ops.affinity_info)
503 * cpu_kill could race with cpu_die and we can
504 * potentially end up declaring this cpu undead
505 * while it is dying. So, try again a few times.
508 for (i = 0; i < 10; i++) {
509 err = psci_ops.affinity_info(cpu_logical_map(cpu), 0);
510 if (err == PSCI_0_2_AFFINITY_LEVEL_OFF) {
511 pr_info("CPU%d killed.\n", cpu);
516 pr_info("Retrying again to check for CPU kill\n");
519 pr_warn("CPU%d may not have shut down cleanly (AFFINITY_INFO reports %d)\n",
521 /* Make op_cpu_kill() fail. */
527 static int psci_suspend_finisher(unsigned long index)
529 struct psci_power_state *state = __this_cpu_read(psci_power_state);
531 return psci_ops.cpu_suspend(state[index - 1],
532 virt_to_phys(cpu_resume));
535 static int __maybe_unused cpu_psci_cpu_suspend(unsigned long index)
538 struct psci_power_state *state = __this_cpu_read(psci_power_state);
540 * idle state index 0 corresponds to wfi, should never be called
541 * from the cpu_suspend operations
543 if (WARN_ON_ONCE(!index))
546 if (state[index - 1].type == PSCI_POWER_STATE_TYPE_STANDBY)
547 ret = psci_ops.cpu_suspend(state[index - 1], 0);
549 ret = __cpu_suspend(index, psci_suspend_finisher);
554 const struct cpu_operations cpu_psci_ops = {
556 #ifdef CONFIG_CPU_IDLE
557 .cpu_init_idle = cpu_psci_cpu_init_idle,
558 .cpu_suspend = cpu_psci_cpu_suspend,
561 .cpu_init = cpu_psci_cpu_init,
562 .cpu_prepare = cpu_psci_cpu_prepare,
563 .cpu_boot = cpu_psci_cpu_boot,
564 #ifdef CONFIG_HOTPLUG_CPU
565 .cpu_disable = cpu_psci_cpu_disable,
566 .cpu_die = cpu_psci_cpu_die,
567 .cpu_kill = cpu_psci_cpu_kill,