mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-24 21:24:00 +08:00
7b01463e51
* pm-sleep: ACPI / PM: Check low power idle constraints for debug only PM / s2idle: Rename platform operations structure PM / s2idle: Rename ->enter_freeze to ->enter_s2idle PM / s2idle: Rename freeze_state enum and related items PM / s2idle: Rename PM_SUSPEND_FREEZE to PM_SUSPEND_TO_IDLE ACPI / PM: Prefer suspend-to-idle over S3 on some systems platform/x86: intel-hid: Wake up Dell Latitude 7275 from suspend-to-idle PM / suspend: Define pr_fmt() in suspend.c PM / suspend: Use mem_sleep_labels[] strings in messages PM / sleep: Put pm_test under CONFIG_PM_SLEEP_DEBUG PM / sleep: Check pm_wakeup_pending() in __device_suspend_noirq() PM / core: Add error argument to dpm_show_time() PM / core: Split dpm_suspend_noirq() and dpm_resume_noirq() PM / s2idle: Rearrange the main suspend-to-idle loop PM / timekeeping: Print debug messages when requested PM / sleep: Mark suspend/hibernation start and finish PM / sleep: Do not print debug messages by default PM / suspend: Export pm_suspend_target_state
230 lines
6.5 KiB
C
230 lines
6.5 KiB
C
/*
|
|
* DT idle states parsing code.
|
|
*
|
|
* Copyright (C) 2014 ARM Ltd.
|
|
* Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
|
|
#define pr_fmt(fmt) "DT idle-states: " fmt
|
|
|
|
#include <linux/cpuidle.h>
|
|
#include <linux/cpumask.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/of.h>
|
|
#include <linux/of_device.h>
|
|
|
|
#include "dt_idle_states.h"
|
|
|
|
static int init_state_node(struct cpuidle_state *idle_state,
|
|
const struct of_device_id *matches,
|
|
struct device_node *state_node)
|
|
{
|
|
int err;
|
|
const struct of_device_id *match_id;
|
|
const char *desc;
|
|
|
|
match_id = of_match_node(matches, state_node);
|
|
if (!match_id)
|
|
return -ENODEV;
|
|
/*
|
|
* CPUidle drivers are expected to initialize the const void *data
|
|
* pointer of the passed in struct of_device_id array to the idle
|
|
* state enter function.
|
|
*/
|
|
idle_state->enter = match_id->data;
|
|
/*
|
|
* Since this is not a "coupled" state, it's safe to assume interrupts
|
|
* won't be enabled when it exits allowing the tick to be frozen
|
|
* safely. So enter() can be also enter_s2idle() callback.
|
|
*/
|
|
idle_state->enter_s2idle = match_id->data;
|
|
|
|
err = of_property_read_u32(state_node, "wakeup-latency-us",
|
|
&idle_state->exit_latency);
|
|
if (err) {
|
|
u32 entry_latency, exit_latency;
|
|
|
|
err = of_property_read_u32(state_node, "entry-latency-us",
|
|
&entry_latency);
|
|
if (err) {
|
|
pr_debug(" * %pOF missing entry-latency-us property\n",
|
|
state_node);
|
|
return -EINVAL;
|
|
}
|
|
|
|
err = of_property_read_u32(state_node, "exit-latency-us",
|
|
&exit_latency);
|
|
if (err) {
|
|
pr_debug(" * %pOF missing exit-latency-us property\n",
|
|
state_node);
|
|
return -EINVAL;
|
|
}
|
|
/*
|
|
* If wakeup-latency-us is missing, default to entry+exit
|
|
* latencies as defined in idle states bindings
|
|
*/
|
|
idle_state->exit_latency = entry_latency + exit_latency;
|
|
}
|
|
|
|
err = of_property_read_u32(state_node, "min-residency-us",
|
|
&idle_state->target_residency);
|
|
if (err) {
|
|
pr_debug(" * %pOF missing min-residency-us property\n",
|
|
state_node);
|
|
return -EINVAL;
|
|
}
|
|
|
|
err = of_property_read_string(state_node, "idle-state-name", &desc);
|
|
if (err)
|
|
desc = state_node->name;
|
|
|
|
idle_state->flags = 0;
|
|
if (of_property_read_bool(state_node, "local-timer-stop"))
|
|
idle_state->flags |= CPUIDLE_FLAG_TIMER_STOP;
|
|
/*
|
|
* TODO:
|
|
* replace with kstrdup and pointer assignment when name
|
|
* and desc become string pointers
|
|
*/
|
|
strncpy(idle_state->name, state_node->name, CPUIDLE_NAME_LEN - 1);
|
|
strncpy(idle_state->desc, desc, CPUIDLE_DESC_LEN - 1);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Check that the idle state is uniform across all CPUs in the CPUidle driver
|
|
* cpumask
|
|
*/
|
|
static bool idle_state_valid(struct device_node *state_node, unsigned int idx,
|
|
const cpumask_t *cpumask)
|
|
{
|
|
int cpu;
|
|
struct device_node *cpu_node, *curr_state_node;
|
|
bool valid = true;
|
|
|
|
/*
|
|
* Compare idle state phandles for index idx on all CPUs in the
|
|
* CPUidle driver cpumask. Start from next logical cpu following
|
|
* cpumask_first(cpumask) since that's the CPU state_node was
|
|
* retrieved from. If a mismatch is found bail out straight
|
|
* away since we certainly hit a firmware misconfiguration.
|
|
*/
|
|
for (cpu = cpumask_next(cpumask_first(cpumask), cpumask);
|
|
cpu < nr_cpu_ids; cpu = cpumask_next(cpu, cpumask)) {
|
|
cpu_node = of_cpu_device_node_get(cpu);
|
|
curr_state_node = of_parse_phandle(cpu_node, "cpu-idle-states",
|
|
idx);
|
|
if (state_node != curr_state_node)
|
|
valid = false;
|
|
|
|
of_node_put(curr_state_node);
|
|
of_node_put(cpu_node);
|
|
if (!valid)
|
|
break;
|
|
}
|
|
|
|
return valid;
|
|
}
|
|
|
|
/**
|
|
* dt_init_idle_driver() - Parse the DT idle states and initialize the
|
|
* idle driver states array
|
|
* @drv: Pointer to CPU idle driver to be initialized
|
|
* @matches: Array of of_device_id match structures to search in for
|
|
* compatible idle state nodes. The data pointer for each valid
|
|
* struct of_device_id entry in the matches array must point to
|
|
* a function with the following signature, that corresponds to
|
|
* the CPUidle state enter function signature:
|
|
*
|
|
* int (*)(struct cpuidle_device *dev,
|
|
* struct cpuidle_driver *drv,
|
|
* int index);
|
|
*
|
|
* @start_idx: First idle state index to be initialized
|
|
*
|
|
* If DT idle states are detected and are valid the state count and states
|
|
* array entries in the cpuidle driver are initialized accordingly starting
|
|
* from index start_idx.
|
|
*
|
|
* Return: number of valid DT idle states parsed, <0 on failure
|
|
*/
|
|
int dt_init_idle_driver(struct cpuidle_driver *drv,
|
|
const struct of_device_id *matches,
|
|
unsigned int start_idx)
|
|
{
|
|
struct cpuidle_state *idle_state;
|
|
struct device_node *state_node, *cpu_node;
|
|
int i, err = 0;
|
|
const cpumask_t *cpumask;
|
|
unsigned int state_idx = start_idx;
|
|
|
|
if (state_idx >= CPUIDLE_STATE_MAX)
|
|
return -EINVAL;
|
|
/*
|
|
* We get the idle states for the first logical cpu in the
|
|
* driver mask (or cpu_possible_mask if the driver cpumask is not set)
|
|
* and we check through idle_state_valid() if they are uniform
|
|
* across CPUs, otherwise we hit a firmware misconfiguration.
|
|
*/
|
|
cpumask = drv->cpumask ? : cpu_possible_mask;
|
|
cpu_node = of_cpu_device_node_get(cpumask_first(cpumask));
|
|
|
|
for (i = 0; ; i++) {
|
|
state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i);
|
|
if (!state_node)
|
|
break;
|
|
|
|
if (!of_device_is_available(state_node)) {
|
|
of_node_put(state_node);
|
|
continue;
|
|
}
|
|
|
|
if (!idle_state_valid(state_node, i, cpumask)) {
|
|
pr_warn("%pOF idle state not valid, bailing out\n",
|
|
state_node);
|
|
err = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
if (state_idx == CPUIDLE_STATE_MAX) {
|
|
pr_warn("State index reached static CPU idle driver states array size\n");
|
|
break;
|
|
}
|
|
|
|
idle_state = &drv->states[state_idx++];
|
|
err = init_state_node(idle_state, matches, state_node);
|
|
if (err) {
|
|
pr_err("Parsing idle state node %pOF failed with err %d\n",
|
|
state_node, err);
|
|
err = -EINVAL;
|
|
break;
|
|
}
|
|
of_node_put(state_node);
|
|
}
|
|
|
|
of_node_put(state_node);
|
|
of_node_put(cpu_node);
|
|
if (err)
|
|
return err;
|
|
/*
|
|
* Update the driver state count only if some valid DT idle states
|
|
* were detected
|
|
*/
|
|
if (i)
|
|
drv->state_count = state_idx;
|
|
|
|
/*
|
|
* Return the number of present and valid DT idle states, which can
|
|
* also be 0 on platforms with missing DT idle states or legacy DT
|
|
* configuration predating the DT idle states bindings.
|
|
*/
|
|
return i;
|
|
}
|
|
EXPORT_SYMBOL_GPL(dt_init_idle_driver);
|