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/init.h>
20 #include <linux/smp.h>
21 #include <linux/reboot.h>
23 #include <linux/delay.h>
24 #include <linux/slab.h>
25 #include <uapi/linux/psci.h>
27 #include <asm/compiler.h>
28 #include <asm/cpu_ops.h>
29 #include <asm/errno.h>
31 #include <asm/smp_plat.h>
32 #include <asm/suspend.h>
33 #include <asm/system_misc.h>
35 #define PSCI_POWER_STATE_TYPE_STANDBY 0
36 #define PSCI_POWER_STATE_TYPE_POWER_DOWN 1
38 struct psci_power_state {
44 struct psci_operations {
45 int (*cpu_suspend)(struct psci_power_state state,
46 unsigned long entry_point);
47 int (*cpu_off)(struct psci_power_state state);
48 int (*cpu_on)(unsigned long cpuid, unsigned long entry_point);
49 int (*migrate)(unsigned long cpuid);
50 int (*affinity_info)(unsigned long target_affinity,
51 unsigned long lowest_affinity_level);
52 int (*migrate_info_type)(void);
55 static struct psci_operations psci_ops;
57 static int (*invoke_psci_fn)(u64, u64, u64, u64);
58 typedef int (*psci_initcall_t)(const struct device_node *);
60 asmlinkage int __invoke_psci_fn_hvc(u64, u64, u64, u64);
61 asmlinkage int __invoke_psci_fn_smc(u64, u64, u64, u64);
68 PSCI_FN_AFFINITY_INFO,
69 PSCI_FN_MIGRATE_INFO_TYPE,
73 static DEFINE_PER_CPU_READ_MOSTLY(struct psci_power_state *, psci_power_state);
75 static u32 psci_function_id[PSCI_FN_MAX];
77 static int psci_to_linux_errno(int errno)
80 case PSCI_RET_SUCCESS:
82 case PSCI_RET_NOT_SUPPORTED:
84 case PSCI_RET_INVALID_PARAMS:
93 static u32 psci_power_state_pack(struct psci_power_state state)
95 return ((state.id << PSCI_0_2_POWER_STATE_ID_SHIFT)
96 & PSCI_0_2_POWER_STATE_ID_MASK) |
97 ((state.type << PSCI_0_2_POWER_STATE_TYPE_SHIFT)
98 & PSCI_0_2_POWER_STATE_TYPE_MASK) |
99 ((state.affinity_level << PSCI_0_2_POWER_STATE_AFFL_SHIFT)
100 & PSCI_0_2_POWER_STATE_AFFL_MASK);
103 static void psci_power_state_unpack(u32 power_state,
104 struct psci_power_state *state)
106 state->id = (power_state & PSCI_0_2_POWER_STATE_ID_MASK) >>
107 PSCI_0_2_POWER_STATE_ID_SHIFT;
108 state->type = (power_state & PSCI_0_2_POWER_STATE_TYPE_MASK) >>
109 PSCI_0_2_POWER_STATE_TYPE_SHIFT;
110 state->affinity_level =
111 (power_state & PSCI_0_2_POWER_STATE_AFFL_MASK) >>
112 PSCI_0_2_POWER_STATE_AFFL_SHIFT;
115 static int psci_get_version(void)
119 err = invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
123 static int psci_cpu_suspend(struct psci_power_state state,
124 unsigned long entry_point)
129 fn = psci_function_id[PSCI_FN_CPU_SUSPEND];
130 power_state = psci_power_state_pack(state);
131 err = invoke_psci_fn(fn, power_state, entry_point, 0);
132 return psci_to_linux_errno(err);
135 static int psci_cpu_off(struct psci_power_state state)
140 fn = psci_function_id[PSCI_FN_CPU_OFF];
141 power_state = psci_power_state_pack(state);
142 err = invoke_psci_fn(fn, power_state, 0, 0);
143 return psci_to_linux_errno(err);
146 static int psci_cpu_on(unsigned long cpuid, unsigned long entry_point)
151 fn = psci_function_id[PSCI_FN_CPU_ON];
152 err = invoke_psci_fn(fn, cpuid, entry_point, 0);
153 return psci_to_linux_errno(err);
156 static int psci_migrate(unsigned long cpuid)
161 fn = psci_function_id[PSCI_FN_MIGRATE];
162 err = invoke_psci_fn(fn, cpuid, 0, 0);
163 return psci_to_linux_errno(err);
166 static int psci_affinity_info(unsigned long target_affinity,
167 unsigned long lowest_affinity_level)
172 fn = psci_function_id[PSCI_FN_AFFINITY_INFO];
173 err = invoke_psci_fn(fn, target_affinity, lowest_affinity_level, 0);
177 static int psci_migrate_info_type(void)
182 fn = psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE];
183 err = invoke_psci_fn(fn, 0, 0, 0);
187 static int __maybe_unused cpu_psci_cpu_init_idle(struct device_node *cpu_node,
190 int i, ret, count = 0;
191 struct psci_power_state *psci_states;
192 struct device_node *state_node;
195 * If the PSCI cpu_suspend function hook has not been initialized
196 * idle states must not be enabled, so bail out
198 if (!psci_ops.cpu_suspend)
201 /* Count idle states */
202 while ((state_node = of_parse_phandle(cpu_node, "cpu-idle-states",
205 of_node_put(state_node);
211 psci_states = kcalloc(count, sizeof(*psci_states), GFP_KERNEL);
215 for (i = 0; i < count; i++) {
216 u32 psci_power_state;
218 state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i);
220 ret = of_property_read_u32(state_node,
221 "arm,psci-suspend-param",
224 pr_warn(" * %s missing arm,psci-suspend-param property\n",
225 state_node->full_name);
226 of_node_put(state_node);
230 of_node_put(state_node);
231 pr_debug("psci-power-state %#x index %d\n", psci_power_state,
233 psci_power_state_unpack(psci_power_state, &psci_states[i]);
235 /* Idle states parsed correctly, initialize per-cpu pointer */
236 per_cpu(psci_power_state, cpu) = psci_states;
244 static int get_set_conduit_method(struct device_node *np)
248 pr_info("probing for conduit method from DT.\n");
250 if (of_property_read_string(np, "method", &method)) {
251 pr_warn("missing \"method\" property\n");
255 if (!strcmp("hvc", method)) {
256 invoke_psci_fn = __invoke_psci_fn_hvc;
257 } else if (!strcmp("smc", method)) {
258 invoke_psci_fn = __invoke_psci_fn_smc;
260 pr_warn("invalid \"method\" property: %s\n", method);
266 static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
268 invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
271 static void psci_sys_poweroff(void)
273 invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
277 * PSCI Function IDs for v0.2+ are well defined so use
280 static int __init psci_0_2_init(struct device_node *np)
284 err = get_set_conduit_method(np);
289 ver = psci_get_version();
291 if (ver == PSCI_RET_NOT_SUPPORTED) {
292 /* PSCI v0.2 mandates implementation of PSCI_ID_VERSION. */
293 pr_err("PSCI firmware does not comply with the v0.2 spec.\n");
297 pr_info("PSCIv%d.%d detected in firmware.\n",
298 PSCI_VERSION_MAJOR(ver),
299 PSCI_VERSION_MINOR(ver));
301 if (PSCI_VERSION_MAJOR(ver) == 0 &&
302 PSCI_VERSION_MINOR(ver) < 2) {
304 pr_err("Conflicting PSCI version detected.\n");
309 pr_info("Using standard PSCI v0.2 function IDs\n");
310 psci_function_id[PSCI_FN_CPU_SUSPEND] = PSCI_0_2_FN64_CPU_SUSPEND;
311 psci_ops.cpu_suspend = psci_cpu_suspend;
313 psci_function_id[PSCI_FN_CPU_OFF] = PSCI_0_2_FN_CPU_OFF;
314 psci_ops.cpu_off = psci_cpu_off;
316 psci_function_id[PSCI_FN_CPU_ON] = PSCI_0_2_FN64_CPU_ON;
317 psci_ops.cpu_on = psci_cpu_on;
319 psci_function_id[PSCI_FN_MIGRATE] = PSCI_0_2_FN64_MIGRATE;
320 psci_ops.migrate = psci_migrate;
322 psci_function_id[PSCI_FN_AFFINITY_INFO] = PSCI_0_2_FN64_AFFINITY_INFO;
323 psci_ops.affinity_info = psci_affinity_info;
325 psci_function_id[PSCI_FN_MIGRATE_INFO_TYPE] =
326 PSCI_0_2_FN_MIGRATE_INFO_TYPE;
327 psci_ops.migrate_info_type = psci_migrate_info_type;
329 arm_pm_restart = psci_sys_reset;
331 pm_power_off = psci_sys_poweroff;
339 * PSCI < v0.2 get PSCI Function IDs via DT.
341 static int __init psci_0_1_init(struct device_node *np)
346 err = get_set_conduit_method(np);
351 pr_info("Using PSCI v0.1 Function IDs from DT\n");
353 if (!of_property_read_u32(np, "cpu_suspend", &id)) {
354 psci_function_id[PSCI_FN_CPU_SUSPEND] = id;
355 psci_ops.cpu_suspend = psci_cpu_suspend;
358 if (!of_property_read_u32(np, "cpu_off", &id)) {
359 psci_function_id[PSCI_FN_CPU_OFF] = id;
360 psci_ops.cpu_off = psci_cpu_off;
363 if (!of_property_read_u32(np, "cpu_on", &id)) {
364 psci_function_id[PSCI_FN_CPU_ON] = id;
365 psci_ops.cpu_on = psci_cpu_on;
368 if (!of_property_read_u32(np, "migrate", &id)) {
369 psci_function_id[PSCI_FN_MIGRATE] = id;
370 psci_ops.migrate = psci_migrate;
378 static const struct of_device_id psci_of_match[] __initconst = {
379 { .compatible = "arm,psci", .data = psci_0_1_init},
380 { .compatible = "arm,psci-0.2", .data = psci_0_2_init},
384 int __init psci_init(void)
386 struct device_node *np;
387 const struct of_device_id *matched_np;
388 psci_initcall_t init_fn;
390 np = of_find_matching_node_and_match(NULL, psci_of_match, &matched_np);
395 init_fn = (psci_initcall_t)matched_np->data;
401 static int __init cpu_psci_cpu_init(struct device_node *dn, unsigned int cpu)
406 static int __init cpu_psci_cpu_prepare(unsigned int cpu)
408 if (!psci_ops.cpu_on) {
409 pr_err("no cpu_on method, not booting CPU%d\n", cpu);
416 static int cpu_psci_cpu_boot(unsigned int cpu)
418 int err = psci_ops.cpu_on(cpu_logical_map(cpu), __pa(secondary_entry));
420 pr_err("failed to boot CPU%d (%d)\n", cpu, err);
425 #ifdef CONFIG_HOTPLUG_CPU
426 static int cpu_psci_cpu_disable(unsigned int cpu)
428 /* Fail early if we don't have CPU_OFF support */
429 if (!psci_ops.cpu_off)
434 static void cpu_psci_cpu_die(unsigned int cpu)
438 * There are no known implementations of PSCI actually using the
439 * power state field, pass a sensible default for now.
441 struct psci_power_state state = {
442 .type = PSCI_POWER_STATE_TYPE_POWER_DOWN,
445 ret = psci_ops.cpu_off(state);
447 pr_crit("unable to power off CPU%u (%d)\n", cpu, ret);
450 static int cpu_psci_cpu_kill(unsigned int cpu)
454 if (!psci_ops.affinity_info)
457 * cpu_kill could race with cpu_die and we can
458 * potentially end up declaring this cpu undead
459 * while it is dying. So, try again a few times.
462 for (i = 0; i < 10; i++) {
463 err = psci_ops.affinity_info(cpu_logical_map(cpu), 0);
464 if (err == PSCI_0_2_AFFINITY_LEVEL_OFF) {
465 pr_info("CPU%d killed.\n", cpu);
470 pr_info("Retrying again to check for CPU kill\n");
473 pr_warn("CPU%d may not have shut down cleanly (AFFINITY_INFO reports %d)\n",
475 /* Make op_cpu_kill() fail. */
481 static int psci_suspend_finisher(unsigned long index)
483 struct psci_power_state *state = __this_cpu_read(psci_power_state);
485 return psci_ops.cpu_suspend(state[index - 1],
486 virt_to_phys(cpu_resume));
489 static int __maybe_unused cpu_psci_cpu_suspend(unsigned long index)
492 struct psci_power_state *state = __this_cpu_read(psci_power_state);
494 * idle state index 0 corresponds to wfi, should never be called
495 * from the cpu_suspend operations
497 if (WARN_ON_ONCE(!index))
500 if (state[index - 1].type == PSCI_POWER_STATE_TYPE_STANDBY)
501 ret = psci_ops.cpu_suspend(state[index - 1], 0);
503 ret = __cpu_suspend(index, psci_suspend_finisher);
508 const struct cpu_operations cpu_psci_ops = {
510 #ifdef CONFIG_CPU_IDLE
511 .cpu_init_idle = cpu_psci_cpu_init_idle,
512 .cpu_suspend = cpu_psci_cpu_suspend,
515 .cpu_init = cpu_psci_cpu_init,
516 .cpu_prepare = cpu_psci_cpu_prepare,
517 .cpu_boot = cpu_psci_cpu_boot,
518 #ifdef CONFIG_HOTPLUG_CPU
519 .cpu_disable = cpu_psci_cpu_disable,
520 .cpu_die = cpu_psci_cpu_die,
521 .cpu_kill = cpu_psci_cpu_kill,