304 lines
6.4 KiB
C
304 lines
6.4 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* PM domains for CPUs via genpd - managed by cpuidle-psci.
|
|
*
|
|
* Copyright (C) 2019 Linaro Ltd.
|
|
* Author: Ulf Hansson <ulf.hansson@linaro.org>
|
|
*
|
|
*/
|
|
|
|
#define pr_fmt(fmt) "CPUidle PSCI: " fmt
|
|
|
|
#include <linux/cpu.h>
|
|
#include <linux/device.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/pm_domain.h>
|
|
#include <linux/pm_runtime.h>
|
|
#include <linux/psci.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/string.h>
|
|
|
|
#include "cpuidle-psci.h"
|
|
|
|
struct psci_pd_provider {
|
|
struct list_head link;
|
|
struct device_node *node;
|
|
};
|
|
|
|
static LIST_HEAD(psci_pd_providers);
|
|
|
|
static int psci_pd_power_off(struct generic_pm_domain *pd)
|
|
{
|
|
struct genpd_power_state *state = &pd->states[pd->state_idx];
|
|
u32 *pd_state;
|
|
|
|
if (!state->data)
|
|
return 0;
|
|
|
|
/* OSI mode is enabled, set the corresponding domain state. */
|
|
pd_state = state->data;
|
|
psci_set_domain_state(*pd_state);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __init psci_pd_parse_state_nodes(struct genpd_power_state *states,
|
|
int state_count)
|
|
{
|
|
int i, ret;
|
|
u32 psci_state, *psci_state_buf;
|
|
|
|
for (i = 0; i < state_count; i++) {
|
|
ret = psci_dt_parse_state_node(to_of_node(states[i].fwnode),
|
|
&psci_state);
|
|
if (ret)
|
|
goto free_state;
|
|
|
|
psci_state_buf = kmalloc(sizeof(u32), GFP_KERNEL);
|
|
if (!psci_state_buf) {
|
|
ret = -ENOMEM;
|
|
goto free_state;
|
|
}
|
|
*psci_state_buf = psci_state;
|
|
states[i].data = psci_state_buf;
|
|
}
|
|
|
|
return 0;
|
|
|
|
free_state:
|
|
i--;
|
|
for (; i >= 0; i--)
|
|
kfree(states[i].data);
|
|
return ret;
|
|
}
|
|
|
|
static int __init psci_pd_parse_states(struct device_node *np,
|
|
struct genpd_power_state **states, int *state_count)
|
|
{
|
|
int ret;
|
|
|
|
/* Parse the domain idle states. */
|
|
ret = of_genpd_parse_idle_states(np, states, state_count);
|
|
if (ret)
|
|
return ret;
|
|
|
|
/* Fill out the PSCI specifics for each found state. */
|
|
ret = psci_pd_parse_state_nodes(*states, *state_count);
|
|
if (ret)
|
|
kfree(*states);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void psci_pd_free_states(struct genpd_power_state *states,
|
|
unsigned int state_count)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < state_count; i++)
|
|
kfree(states[i].data);
|
|
kfree(states);
|
|
}
|
|
|
|
static int __init psci_pd_init(struct device_node *np)
|
|
{
|
|
struct generic_pm_domain *pd;
|
|
struct psci_pd_provider *pd_provider;
|
|
struct dev_power_governor *pd_gov;
|
|
struct genpd_power_state *states = NULL;
|
|
int ret = -ENOMEM, state_count = 0;
|
|
|
|
pd = kzalloc(sizeof(*pd), GFP_KERNEL);
|
|
if (!pd)
|
|
goto out;
|
|
|
|
pd_provider = kzalloc(sizeof(*pd_provider), GFP_KERNEL);
|
|
if (!pd_provider)
|
|
goto free_pd;
|
|
|
|
pd->name = kasprintf(GFP_KERNEL, "%pOF", np);
|
|
if (!pd->name)
|
|
goto free_pd_prov;
|
|
|
|
/*
|
|
* Parse the domain idle states and let genpd manage the state selection
|
|
* for those being compatible with "domain-idle-state".
|
|
*/
|
|
ret = psci_pd_parse_states(np, &states, &state_count);
|
|
if (ret)
|
|
goto free_name;
|
|
|
|
pd->free_states = psci_pd_free_states;
|
|
pd->name = kbasename(pd->name);
|
|
pd->power_off = psci_pd_power_off;
|
|
pd->states = states;
|
|
pd->state_count = state_count;
|
|
pd->flags |= GENPD_FLAG_IRQ_SAFE | GENPD_FLAG_CPU_DOMAIN;
|
|
|
|
/* Use governor for CPU PM domains if it has some states to manage. */
|
|
pd_gov = state_count > 0 ? &pm_domain_cpu_gov : NULL;
|
|
|
|
ret = pm_genpd_init(pd, pd_gov, false);
|
|
if (ret) {
|
|
psci_pd_free_states(states, state_count);
|
|
goto free_name;
|
|
}
|
|
|
|
ret = of_genpd_add_provider_simple(np, pd);
|
|
if (ret)
|
|
goto remove_pd;
|
|
|
|
pd_provider->node = of_node_get(np);
|
|
list_add(&pd_provider->link, &psci_pd_providers);
|
|
|
|
pr_debug("init PM domain %s\n", pd->name);
|
|
return 0;
|
|
|
|
remove_pd:
|
|
pm_genpd_remove(pd);
|
|
free_name:
|
|
kfree(pd->name);
|
|
free_pd_prov:
|
|
kfree(pd_provider);
|
|
free_pd:
|
|
kfree(pd);
|
|
out:
|
|
pr_err("failed to init PM domain ret=%d %pOF\n", ret, np);
|
|
return ret;
|
|
}
|
|
|
|
static void __init psci_pd_remove(void)
|
|
{
|
|
struct psci_pd_provider *pd_provider, *it;
|
|
struct generic_pm_domain *genpd;
|
|
|
|
list_for_each_entry_safe(pd_provider, it, &psci_pd_providers, link) {
|
|
of_genpd_del_provider(pd_provider->node);
|
|
|
|
genpd = of_genpd_remove_last(pd_provider->node);
|
|
if (!IS_ERR(genpd))
|
|
kfree(genpd);
|
|
|
|
of_node_put(pd_provider->node);
|
|
list_del(&pd_provider->link);
|
|
kfree(pd_provider);
|
|
}
|
|
}
|
|
|
|
static int __init psci_pd_init_topology(struct device_node *np, bool add)
|
|
{
|
|
struct device_node *node;
|
|
struct of_phandle_args child, parent;
|
|
int ret;
|
|
|
|
for_each_child_of_node(np, node) {
|
|
if (of_parse_phandle_with_args(node, "power-domains",
|
|
"#power-domain-cells", 0, &parent))
|
|
continue;
|
|
|
|
child.np = node;
|
|
child.args_count = 0;
|
|
|
|
ret = add ? of_genpd_add_subdomain(&parent, &child) :
|
|
of_genpd_remove_subdomain(&parent, &child);
|
|
of_node_put(parent.np);
|
|
if (ret) {
|
|
of_node_put(node);
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __init psci_pd_add_topology(struct device_node *np)
|
|
{
|
|
return psci_pd_init_topology(np, true);
|
|
}
|
|
|
|
static void __init psci_pd_remove_topology(struct device_node *np)
|
|
{
|
|
psci_pd_init_topology(np, false);
|
|
}
|
|
|
|
static const struct of_device_id psci_of_match[] __initconst = {
|
|
{ .compatible = "arm,psci-1.0" },
|
|
{}
|
|
};
|
|
|
|
static int __init psci_idle_init_domains(void)
|
|
{
|
|
struct device_node *np = of_find_matching_node(NULL, psci_of_match);
|
|
struct device_node *node;
|
|
int ret = 0, pd_count = 0;
|
|
|
|
if (!np)
|
|
return -ENODEV;
|
|
|
|
/* Currently limit the hierarchical topology to be used in OSI mode. */
|
|
if (!psci_has_osi_support())
|
|
goto out;
|
|
|
|
/*
|
|
* Parse child nodes for the "#power-domain-cells" property and
|
|
* initialize a genpd/genpd-of-provider pair when it's found.
|
|
*/
|
|
for_each_child_of_node(np, node) {
|
|
if (!of_find_property(node, "#power-domain-cells", NULL))
|
|
continue;
|
|
|
|
ret = psci_pd_init(node);
|
|
if (ret)
|
|
goto put_node;
|
|
|
|
pd_count++;
|
|
}
|
|
|
|
/* Bail out if not using the hierarchical CPU topology. */
|
|
if (!pd_count)
|
|
goto out;
|
|
|
|
/* Link genpd masters/subdomains to model the CPU topology. */
|
|
ret = psci_pd_add_topology(np);
|
|
if (ret)
|
|
goto remove_pd;
|
|
|
|
/* Try to enable OSI mode. */
|
|
ret = psci_set_osi_mode();
|
|
if (ret) {
|
|
pr_warn("failed to enable OSI mode: %d\n", ret);
|
|
psci_pd_remove_topology(np);
|
|
goto remove_pd;
|
|
}
|
|
|
|
of_node_put(np);
|
|
pr_info("Initialized CPU PM domain topology\n");
|
|
return pd_count;
|
|
|
|
put_node:
|
|
of_node_put(node);
|
|
remove_pd:
|
|
if (pd_count)
|
|
psci_pd_remove();
|
|
pr_err("failed to create CPU PM domains ret=%d\n", ret);
|
|
out:
|
|
of_node_put(np);
|
|
return ret;
|
|
}
|
|
subsys_initcall(psci_idle_init_domains);
|
|
|
|
struct device __init *psci_dt_attach_cpu(int cpu)
|
|
{
|
|
struct device *dev;
|
|
|
|
dev = dev_pm_domain_attach_by_name(get_cpu_device(cpu), "psci");
|
|
if (IS_ERR_OR_NULL(dev))
|
|
return dev;
|
|
|
|
pm_runtime_irq_safe(dev);
|
|
if (cpu_online(cpu))
|
|
pm_runtime_get_sync(dev);
|
|
|
|
return dev;
|
|
}
|