[PATCH v6 5/8] cpuidle: Factor-out power domain related code from PSCI domain driver

From: Anup Patel
Date: Wed Jun 09 2021 - 08:28:16 EST


The generic power domain related code in PSCI domain driver is largely
independent of PSCI and can be shared with RISC-V SBI domain driver
hence we factor-out this code into dt_idle_genpd.c and dt_idle_genpd.h.

Signed-off-by: Anup Patel <anup.patel@xxxxxxx>
Reviewed-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
---
MAINTAINERS | 7 +
drivers/cpuidle/Kconfig | 4 +
drivers/cpuidle/Kconfig.arm | 1 +
drivers/cpuidle/Makefile | 1 +
drivers/cpuidle/cpuidle-psci-domain.c | 138 +-------------------
drivers/cpuidle/cpuidle-psci.h | 15 ++-
drivers/cpuidle/dt_idle_genpd.c | 177 ++++++++++++++++++++++++++
drivers/cpuidle/dt_idle_genpd.h | 50 ++++++++
8 files changed, 258 insertions(+), 135 deletions(-)
create mode 100644 drivers/cpuidle/dt_idle_genpd.c
create mode 100644 drivers/cpuidle/dt_idle_genpd.h

diff --git a/MAINTAINERS b/MAINTAINERS
index b706dd20ff2b..5108b5058502 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4789,6 +4789,13 @@ S: Supported
F: drivers/cpuidle/cpuidle-psci.h
F: drivers/cpuidle/cpuidle-psci-domain.c

+CPUIDLE DRIVER - DT IDLE PM DOMAIN
+M: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
+L: linux-pm@xxxxxxxxxxxxxxx
+S: Supported
+F: drivers/cpuidle/dt_idle_genpd.c
+F: drivers/cpuidle/dt_idle_genpd.h
+
CRAMFS FILESYSTEM
M: Nicolas Pitre <nico@xxxxxxxxxxx>
S: Maintained
diff --git a/drivers/cpuidle/Kconfig b/drivers/cpuidle/Kconfig
index c0aeedd66f02..f1afe7ab6b54 100644
--- a/drivers/cpuidle/Kconfig
+++ b/drivers/cpuidle/Kconfig
@@ -47,6 +47,10 @@ config CPU_IDLE_GOV_HALTPOLL
config DT_IDLE_STATES
bool

+config DT_IDLE_GENPD
+ depends on PM_GENERIC_DOMAINS_OF
+ bool
+
menu "ARM CPU Idle Drivers"
depends on ARM || ARM64
source "drivers/cpuidle/Kconfig.arm"
diff --git a/drivers/cpuidle/Kconfig.arm b/drivers/cpuidle/Kconfig.arm
index 334f83e56120..be12a9ca78f0 100644
--- a/drivers/cpuidle/Kconfig.arm
+++ b/drivers/cpuidle/Kconfig.arm
@@ -27,6 +27,7 @@ config ARM_PSCI_CPUIDLE_DOMAIN
bool "PSCI CPU idle Domain"
depends on ARM_PSCI_CPUIDLE
depends on PM_GENERIC_DOMAINS_OF
+ select DT_IDLE_GENPD
default y
help
Select this to enable the PSCI based CPUidle driver to use PM domains,
diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile
index 26bbc5e74123..11a26cef279f 100644
--- a/drivers/cpuidle/Makefile
+++ b/drivers/cpuidle/Makefile
@@ -6,6 +6,7 @@
obj-y += cpuidle.o driver.o governor.o sysfs.o governors/
obj-$(CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED) += coupled.o
obj-$(CONFIG_DT_IDLE_STATES) += dt_idle_states.o
+obj-$(CONFIG_DT_IDLE_GENPD) += dt_idle_genpd.o
obj-$(CONFIG_ARCH_HAS_CPU_RELAX) += poll_state.o
obj-$(CONFIG_HALTPOLL_CPUIDLE) += cpuidle-haltpoll.o

diff --git a/drivers/cpuidle/cpuidle-psci-domain.c b/drivers/cpuidle/cpuidle-psci-domain.c
index ff2c3f8e4668..755bbdfc5b82 100644
--- a/drivers/cpuidle/cpuidle-psci-domain.c
+++ b/drivers/cpuidle/cpuidle-psci-domain.c
@@ -47,73 +47,14 @@ static int psci_pd_power_off(struct generic_pm_domain *pd)
return 0;
}

-static int 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 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 psci_pd_init(struct device_node *np, bool use_osi)
{
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);
+ pd = dt_idle_pd_alloc(np, psci_dt_parse_state_node);
if (!pd)
goto out;

@@ -121,22 +62,6 @@ static int psci_pd_init(struct device_node *np, bool use_osi)
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->states = states;
- pd->state_count = state_count;
pd->flags |= GENPD_FLAG_IRQ_SAFE | GENPD_FLAG_CPU_DOMAIN;

/* Allow power off when OSI has been successfully enabled. */
@@ -149,10 +74,8 @@ static int psci_pd_init(struct device_node *np, bool use_osi)
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;
- }
+ if (ret)
+ goto free_pd_prov;

ret = of_genpd_add_provider_simple(np, pd);
if (ret)
@@ -166,12 +89,10 @@ static int psci_pd_init(struct device_node *np, bool use_osi)

remove_pd:
pm_genpd_remove(pd);
-free_name:
- kfree(pd->name);
free_pd_prov:
kfree(pd_provider);
free_pd:
- kfree(pd);
+ dt_idle_pd_free(pd);
out:
pr_err("failed to init PM domain ret=%d %pOF\n", ret, np);
return ret;
@@ -195,30 +116,6 @@ static void psci_pd_remove(void)
}
}

-static int psci_pd_init_topology(struct device_node *np)
-{
- 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 = of_genpd_add_subdomain(&parent, &child);
- of_node_put(parent.np);
- if (ret) {
- of_node_put(node);
- return ret;
- }
- }
-
- return 0;
-}
-
static bool psci_pd_try_set_osi_mode(void)
{
int ret;
@@ -282,7 +179,7 @@ static int psci_cpuidle_domain_probe(struct platform_device *pdev)
goto no_pd;

/* Link genpd masters/subdomains to model the CPU topology. */
- ret = psci_pd_init_topology(np);
+ ret = dt_idle_pd_init_topology(np);
if (ret)
goto remove_pd;

@@ -314,28 +211,3 @@ static int __init psci_idle_init_domains(void)
return platform_driver_register(&psci_cpuidle_domain_driver);
}
subsys_initcall(psci_idle_init_domains);
-
-struct device *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);
-
- dev_pm_syscore_device(dev, true);
-
- return dev;
-}
-
-void psci_dt_detach_cpu(struct device *dev)
-{
- if (IS_ERR_OR_NULL(dev))
- return;
-
- dev_pm_domain_detach(dev, false);
-}
diff --git a/drivers/cpuidle/cpuidle-psci.h b/drivers/cpuidle/cpuidle-psci.h
index d8e925e84c27..4e132640ed64 100644
--- a/drivers/cpuidle/cpuidle-psci.h
+++ b/drivers/cpuidle/cpuidle-psci.h
@@ -10,8 +10,19 @@ void psci_set_domain_state(u32 state);
int psci_dt_parse_state_node(struct device_node *np, u32 *state);

#ifdef CONFIG_ARM_PSCI_CPUIDLE_DOMAIN
-struct device *psci_dt_attach_cpu(int cpu);
-void psci_dt_detach_cpu(struct device *dev);
+
+#include "dt_idle_genpd.h"
+
+static inline struct device *psci_dt_attach_cpu(int cpu)
+{
+ return dt_idle_attach_cpu(cpu, "psci");
+}
+
+static inline void psci_dt_detach_cpu(struct device *dev)
+{
+ dt_idle_detach_cpu(dev);
+}
+
#else
static inline struct device *psci_dt_attach_cpu(int cpu) { return NULL; }
static inline void psci_dt_detach_cpu(struct device *dev) { }
diff --git a/drivers/cpuidle/dt_idle_genpd.c b/drivers/cpuidle/dt_idle_genpd.c
new file mode 100644
index 000000000000..db385fd2507e
--- /dev/null
+++ b/drivers/cpuidle/dt_idle_genpd.c
@@ -0,0 +1,177 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * PM domains for CPUs via genpd.
+ *
+ * Copyright (C) 2019 Linaro Ltd.
+ * Author: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
+ *
+ * Copyright (c) 2021 Western Digital Corporation or its affiliates.
+ */
+
+#define pr_fmt(fmt) "dt-idle-genpd: " 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/slab.h>
+#include <linux/string.h>
+
+#include "dt_idle_genpd.h"
+
+static int pd_parse_state_nodes(
+ int (*parse_state)(struct device_node *, u32 *),
+ struct genpd_power_state *states, int state_count)
+{
+ int i, ret;
+ u32 state, *state_buf;
+
+ for (i = 0; i < state_count; i++) {
+ ret = parse_state(to_of_node(states[i].fwnode), &state);
+ if (ret)
+ goto free_state;
+
+ state_buf = kmalloc(sizeof(u32), GFP_KERNEL);
+ if (!state_buf) {
+ ret = -ENOMEM;
+ goto free_state;
+ }
+ *state_buf = state;
+ states[i].data = state_buf;
+ }
+
+ return 0;
+
+free_state:
+ i--;
+ for (; i >= 0; i--)
+ kfree(states[i].data);
+ return ret;
+}
+
+static int pd_parse_states(struct device_node *np,
+ int (*parse_state)(struct device_node *, u32 *),
+ 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 dt specifics for each found state. */
+ ret = pd_parse_state_nodes(parse_state, *states, *state_count);
+ if (ret)
+ kfree(*states);
+
+ return ret;
+}
+
+static void 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);
+}
+
+void dt_idle_pd_free(struct generic_pm_domain *pd)
+{
+ pd_free_states(pd->states, pd->state_count);
+ kfree(pd->name);
+ kfree(pd);
+}
+
+struct generic_pm_domain *dt_idle_pd_alloc(struct device_node *np,
+ int (*parse_state)(struct device_node *, u32 *))
+{
+ struct generic_pm_domain *pd;
+ struct genpd_power_state *states = NULL;
+ int ret, state_count = 0;
+
+ pd = kzalloc(sizeof(*pd), GFP_KERNEL);
+ if (!pd)
+ goto out;
+
+ pd->name = kasprintf(GFP_KERNEL, "%pOF", np);
+ if (!pd->name)
+ goto free_pd;
+
+ /*
+ * Parse the domain idle states and let genpd manage the state selection
+ * for those being compatible with "domain-idle-state".
+ */
+ ret = pd_parse_states(np, parse_state, &states, &state_count);
+ if (ret)
+ goto free_name;
+
+ pd->free_states = pd_free_states;
+ pd->name = kbasename(pd->name);
+ pd->states = states;
+ pd->state_count = state_count;
+
+ pr_debug("alloc PM domain %s\n", pd->name);
+ return pd;
+
+free_name:
+ kfree(pd->name);
+free_pd:
+ kfree(pd);
+out:
+ pr_err("failed to alloc PM domain %pOF\n", np);
+ return NULL;
+}
+
+int dt_idle_pd_init_topology(struct device_node *np)
+{
+ 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 = of_genpd_add_subdomain(&parent, &child);
+ of_node_put(parent.np);
+ if (ret) {
+ of_node_put(node);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+struct device *dt_idle_attach_cpu(int cpu, const char *name)
+{
+ struct device *dev;
+
+ dev = dev_pm_domain_attach_by_name(get_cpu_device(cpu), name);
+ if (IS_ERR_OR_NULL(dev))
+ return dev;
+
+ pm_runtime_irq_safe(dev);
+ if (cpu_online(cpu))
+ pm_runtime_get_sync(dev);
+
+ dev_pm_syscore_device(dev, true);
+
+ return dev;
+}
+
+void dt_idle_detach_cpu(struct device *dev)
+{
+ if (IS_ERR_OR_NULL(dev))
+ return;
+
+ dev_pm_domain_detach(dev, false);
+}
diff --git a/drivers/cpuidle/dt_idle_genpd.h b/drivers/cpuidle/dt_idle_genpd.h
new file mode 100644
index 000000000000..a95483d08a02
--- /dev/null
+++ b/drivers/cpuidle/dt_idle_genpd.h
@@ -0,0 +1,50 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __DT_IDLE_GENPD
+#define __DT_IDLE_GENPD
+
+struct device_node;
+struct generic_pm_domain;
+
+#ifdef CONFIG_DT_IDLE_GENPD
+
+void dt_idle_pd_free(struct generic_pm_domain *pd);
+
+struct generic_pm_domain *dt_idle_pd_alloc(struct device_node *np,
+ int (*parse_state)(struct device_node *, u32 *));
+
+int dt_idle_pd_init_topology(struct device_node *np);
+
+struct device *dt_idle_attach_cpu(int cpu, const char *name);
+
+void dt_idle_detach_cpu(struct device *dev);
+
+#else
+
+static inline void dt_idle_pd_free(struct generic_pm_domain *pd)
+{
+}
+
+static inline struct generic_pm_domain *dt_idle_pd_alloc(
+ struct device_node *np,
+ int (*parse_state)(struct device_node *, u32 *))
+{
+ return NULL;
+}
+
+static inline int dt_idle_pd_init_topology(struct device_node *np)
+{
+ return 0;
+}
+
+static inline struct device *dt_idle_attach_cpu(int cpu, const char *name)
+{
+ return NULL;
+}
+
+static inline void dt_idle_detach_cpu(struct device *dev)
+{
+}
+
+#endif
+
+#endif
--
2.25.1