This patch involves moving the current pseries_idle backend driver code
from pseries/processor_idle.c to drivers/cpuidle/cpuidle-ibm-power.c.
It enables the support for pseries platform, such that going forward the
same code with minimal efforts can be re-used for a common driver on powernv
This removes a lot of code duplicacy, thus making the code elegant.
Signed-off-by: Deepthi Dharwar <deepthi@xxxxxxxxxxxxxxxxxx>
---
arch/powerpc/include/asm/processor.h | 2
arch/powerpc/platforms/pseries/Kconfig | 9 -
arch/powerpc/platforms/pseries/Makefile | 1
arch/powerpc/platforms/pseries/processor_idle.c | 360 -----------------------
drivers/cpuidle/Kconfig | 7
drivers/cpuidle/Makefile | 2
drivers/cpuidle/cpuidle-ibm-power.c | 304 +++++++++++++++++++
7 files changed, 314 insertions(+), 371 deletions(-)
delete mode 100644 arch/powerpc/platforms/pseries/processor_idle.c
create mode 100644 drivers/cpuidle/cpuidle-ibm-power.c
diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h
index e378ccc..ab444ff 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -430,7 +430,7 @@ enum idle_boot_override {IDLE_NO_OVERRIDE = 0, IDLE_POWERSAVE_OFF};
extern int powersave_nap; /* set if nap mode can be used in idle loop */
extern void power7_nap(void);
-#ifdef CONFIG_PSERIES_IDLE
+#ifdef CONFIG_CPU_IDLE_IBM_POWER
extern void update_smt_snooze_delay(int cpu, int residency);
#else
static inline void update_smt_snooze_delay(int cpu, int residency) {}
diff --git a/arch/powerpc/platforms/pseries/Kconfig b/arch/powerpc/platforms/pseries/Kconfig
index 62b4f80..bb59bb0 100644
--- a/arch/powerpc/platforms/pseries/Kconfig
+++ b/arch/powerpc/platforms/pseries/Kconfig
@@ -119,12 +119,3 @@ config DTL
which are accessible through a debugfs file.
Say N if you are unsure.
-
-config PSERIES_IDLE
- bool "Cpuidle driver for pSeries platforms"
- depends on CPU_IDLE
- depends on PPC_PSERIES
- default y
- help
- Select this option to enable processor idle state management
- through cpuidle subsystem.
diff --git a/arch/powerpc/platforms/pseries/Makefile b/arch/powerpc/platforms/pseries/Makefile
index 8ae0103..4b22379 100644
--- a/arch/powerpc/platforms/pseries/Makefile
+++ b/arch/powerpc/platforms/pseries/Makefile
@@ -21,7 +21,6 @@ obj-$(CONFIG_HCALL_STATS) += hvCall_inst.o
obj-$(CONFIG_CMM) += cmm.o
obj-$(CONFIG_DTL) += dtl.o
obj-$(CONFIG_IO_EVENT_IRQ) += io_event_irq.o
-obj-$(CONFIG_PSERIES_IDLE) += processor_idle.o
ifeq ($(CONFIG_PPC_PSERIES),y)
obj-$(CONFIG_SUSPEND) += suspend.o
diff --git a/arch/powerpc/platforms/pseries/processor_idle.c b/arch/powerpc/platforms/pseries/processor_idle.c
deleted file mode 100644
index c905b99..0000000
--- a/arch/powerpc/platforms/pseries/processor_idle.c
+++ /dev/null
@@ -1,360 +0,0 @@
-/*
- * processor_idle - idle state cpuidle driver.
- * Adapted from drivers/idle/intel_idle.c and
- * drivers/acpi/processor_idle.c
- *
- */
-
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/moduleparam.h>
-#include <linux/cpuidle.h>
-#include <linux/cpu.h>
-#include <linux/notifier.h>
-
-#include <asm/paca.h>
-#include <asm/reg.h>
-#include <asm/machdep.h>
-#include <asm/firmware.h>
-#include <asm/runlatch.h>
-#include <asm/plpar_wrappers.h>
-
-struct cpuidle_driver pseries_idle_driver = {
- .name = "pseries_idle",
- .owner = THIS_MODULE,
-};
-
-#define MAX_IDLE_STATE_COUNT 2
-
-static int max_idle_state = MAX_IDLE_STATE_COUNT - 1;
-static struct cpuidle_device __percpu *pseries_cpuidle_devices;
-static struct cpuidle_state *cpuidle_state_table;
-
-static inline void idle_loop_prolog(unsigned long *in_purr)
-{
- *in_purr = mfspr(SPRN_PURR);
- /*
- * Indicate to the HV that we are idle. Now would be
- * a good time to find other work to dispatch.
- */
- get_lppaca()->idle = 1;
-}
-
-static inline void idle_loop_epilog(unsigned long in_purr)
-{
- get_lppaca()->wait_state_cycles += mfspr(SPRN_PURR) - in_purr;
- get_lppaca()->idle = 0;
-}
-
-static int snooze_loop(struct cpuidle_device *dev,
- struct cpuidle_driver *drv,
- int index)
-{
- unsigned long in_purr;
- int cpu = dev->cpu;
-
- idle_loop_prolog(&in_purr);
- local_irq_enable();
- set_thread_flag(TIF_POLLING_NRFLAG);
-
- while ((!need_resched()) && cpu_online(cpu)) {
- ppc64_runlatch_off();
- HMT_low();
- HMT_very_low();
- }
-
- HMT_medium();
- clear_thread_flag(TIF_POLLING_NRFLAG);
- smp_mb();
-
- idle_loop_epilog(in_purr);
-
- return index;
-}
-
-static void check_and_cede_processor(void)
-{
- /*
- * Ensure our interrupt state is properly tracked,
- * also checks if no interrupt has occurred while we
- * were soft-disabled
- */
- if (prep_irq_for_idle()) {
- cede_processor();
-#ifdef CONFIG_TRACE_IRQFLAGS
- /* Ensure that H_CEDE returns with IRQs on */
- if (WARN_ON(!(mfmsr() & MSR_EE)))
- __hard_irq_enable();
-#endif
- }
-}
-
-static int dedicated_cede_loop(struct cpuidle_device *dev,
- struct cpuidle_driver *drv,
- int index)
-{
- unsigned long in_purr;
-
- idle_loop_prolog(&in_purr);
- get_lppaca()->donate_dedicated_cpu = 1;
-
- ppc64_runlatch_off();
- HMT_medium();
- check_and_cede_processor();
-
- get_lppaca()->donate_dedicated_cpu = 0;
-
- idle_loop_epilog(in_purr);
-
- return index;
-}
-
-static int shared_cede_loop(struct cpuidle_device *dev,
- struct cpuidle_driver *drv,
- int index)
-{
- unsigned long in_purr;
-
- idle_loop_prolog(&in_purr);
-
- /*
- * Yield the processor to the hypervisor. We return if
- * an external interrupt occurs (which are driven prior
- * to returning here) or if a prod occurs from another
- * processor. When returning here, external interrupts
- * are enabled.
- */
- check_and_cede_processor();
-
- idle_loop_epilog(in_purr);
-
- return index;
-}
-
-/*
- * States for dedicated partition case.
- */
-static struct cpuidle_state dedicated_states[MAX_IDLE_STATE_COUNT] = {
- { /* Snooze */
- .name = "snooze",
- .desc = "snooze",
- .flags = CPUIDLE_FLAG_TIME_VALID,
- .exit_latency = 0,
- .target_residency = 0,
- .enter = &snooze_loop },
- { /* CEDE */
- .name = "CEDE",
- .desc = "CEDE",
- .flags = CPUIDLE_FLAG_TIME_VALID,
- .exit_latency = 10,
- .target_residency = 100,
- .enter = &dedicated_cede_loop },
-};
-
-/*
- * States for shared partition case.
- */
-static struct cpuidle_state shared_states[MAX_IDLE_STATE_COUNT] = {
- { /* Shared Cede */
- .name = "Shared Cede",
- .desc = "Shared Cede",
- .flags = CPUIDLE_FLAG_TIME_VALID,
- .exit_latency = 0,
- .target_residency = 0,
- .enter = &shared_cede_loop },
-};
-
-void update_smt_snooze_delay(int cpu, int residency)
-{
- struct cpuidle_driver *drv = cpuidle_get_driver();
- struct cpuidle_device *dev = per_cpu(cpuidle_devices, cpu);
-
- if (cpuidle_state_table != dedicated_states)
- return;
-
- if (residency < 0) {
- /* Disable the Nap state on that cpu */
- if (dev)
- dev->states_usage[1].disable = 1;
- } else
- if (drv)
- drv->states[1].target_residency = residency;
-}
-
-static int pseries_cpuidle_add_cpu_notifier(struct notifier_block *n,
- unsigned long action, void *hcpu)
-{
- int hotcpu = (unsigned long)hcpu;
- struct cpuidle_device *dev =
- per_cpu_ptr(pseries_cpuidle_devices, hotcpu);
-
- if (dev && cpuidle_get_driver()) {
- switch (action) {
- case CPU_ONLINE:
- case CPU_ONLINE_FROZEN:
- cpuidle_pause_and_lock();
- cpuidle_enable_device(dev);
- cpuidle_resume_and_unlock();
- break;
-
- case CPU_DEAD:
- case CPU_DEAD_FROZEN:
- cpuidle_pause_and_lock();
- cpuidle_disable_device(dev);
- cpuidle_resume_and_unlock();
- break;
-
- default:
- return NOTIFY_DONE;
- }
- }
- return NOTIFY_OK;
-}
-
-static struct notifier_block setup_hotplug_notifier = {
- .notifier_call = pseries_cpuidle_add_cpu_notifier,
-};
-
-/*
- * pseries_cpuidle_driver_init()
- */
-static int pseries_cpuidle_driver_init(void)
-{
- int idle_state;
- struct cpuidle_driver *drv = &pseries_idle_driver;
-
- drv->state_count = 0;
-
- for (idle_state = 0; idle_state < MAX_IDLE_STATE_COUNT; ++idle_state) {
-
- if (idle_state > max_idle_state)
- break;
-
- /* is the state not enabled? */
- if (cpuidle_state_table[idle_state].enter == NULL)
- continue;
-
- drv->states[drv->state_count] = /* structure copy */
- cpuidle_state_table[idle_state];
-
- drv->state_count += 1;
- }
-
- return 0;
-}
-
-/* pseries_idle_devices_uninit(void)
- * unregister cpuidle devices and de-allocate memory
- */
-static void pseries_idle_devices_uninit(void)
-{
- int i;
- struct cpuidle_device *dev;
-
- for_each_possible_cpu(i) {
- dev = per_cpu_ptr(pseries_cpuidle_devices, i);
- cpuidle_unregister_device(dev);
- }
-
- free_percpu(pseries_cpuidle_devices);
- return;
-}
-
-/* pseries_idle_devices_init()
- * allocate, initialize and register cpuidle device
- */
-static int pseries_idle_devices_init(void)
-{
- int i;
- struct cpuidle_driver *drv = &pseries_idle_driver;
- struct cpuidle_device *dev;
-
- pseries_cpuidle_devices = alloc_percpu(struct cpuidle_device);
- if (pseries_cpuidle_devices == NULL)
- return -ENOMEM;
-
- for_each_possible_cpu(i) {
- dev = per_cpu_ptr(pseries_cpuidle_devices, i);
- dev->state_count = drv->state_count;
- dev->cpu = i;
- if (cpuidle_register_device(dev)) {
- printk(KERN_DEBUG \
- "cpuidle_register_device %d failed!\n", i);
- return -EIO;
- }
- }
-
- return 0;
-}
-
-/*
- * pseries_idle_probe()
- * Choose state table for shared versus dedicated partition
- */
-static int pseries_idle_probe(void)
-{
-
- if (!firmware_has_feature(FW_FEATURE_SPLPAR))
- return -ENODEV;
-
- if (cpuidle_disable != IDLE_NO_OVERRIDE)
- return -ENODEV;
-
- if (max_idle_state == 0) {
- printk(KERN_DEBUG "pseries processor idle disabled.\n");
- return -EPERM;
- }
-
- if (get_lppaca()->shared_proc)
- cpuidle_state_table = shared_states;
- else
- cpuidle_state_table = dedicated_states;
-
- return 0;
-}
-
-static int __init pseries_processor_idle_init(void)
-{
- int retval;
-
- retval = pseries_idle_probe();
- if (retval)
- return retval;
-
- pseries_cpuidle_driver_init();
- retval = cpuidle_register_driver(&pseries_idle_driver);
- if (retval) {
- printk(KERN_DEBUG "Registration of pseries driver failed.\n");
- return retval;
- }
-
- retval = pseries_idle_devices_init();
- if (retval) {
- pseries_idle_devices_uninit();
- cpuidle_unregister_driver(&pseries_idle_driver);
- return retval;
- }
-
- register_cpu_notifier(&setup_hotplug_notifier);
- printk(KERN_DEBUG "pseries_idle_driver registered\n");
-
- return 0;
-}
-
-static void __exit pseries_processor_idle_exit(void)
-{
-
- unregister_cpu_notifier(&setup_hotplug_notifier);
- pseries_idle_devices_uninit();
- cpuidle_unregister_driver(&pseries_idle_driver);
-
- return;
-}
-
-module_init(pseries_processor_idle_init);
-module_exit(pseries_processor_idle_exit);
-
-MODULE_AUTHOR("Deepthi Dharwar <deepthi@xxxxxxxxxxxxxxxxxx>");
-MODULE_DESCRIPTION("Cpuidle driver for POWER");
-MODULE_LICENSE("GPL");
diff --git a/drivers/cpuidle/Kconfig b/drivers/cpuidle/Kconfig
index 0e2cd5c..e805dcd 100644
--- a/drivers/cpuidle/Kconfig
+++ b/drivers/cpuidle/Kconfig
@@ -42,6 +42,13 @@ config CPU_IDLE_ZYNQ
help
Select this to enable cpuidle on Xilinx Zynq processors.
+config CPU_IDLE_IBM_POWER
+ bool "CPU Idle driver for IBM POWER platforms"
+ depends on PPC_PSERIES || PPC_POWERNV
+ default y
+ help
+ Select this option to enable processor idle state management
+ on IBM POWER platform.
endif
config ARCH_NEEDS_CPU_IDLE_COUPLED
diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile
index 8767a7b..b6c8092 100644
--- a/drivers/cpuidle/Makefile
+++ b/drivers/cpuidle/Makefile
@@ -8,3 +8,5 @@ obj-$(CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED) += coupled.o
obj-$(CONFIG_CPU_IDLE_CALXEDA) += cpuidle-calxeda.o
obj-$(CONFIG_ARCH_KIRKWOOD) += cpuidle-kirkwood.o
obj-$(CONFIG_CPU_IDLE_ZYNQ) += cpuidle-zynq.o
+
+obj-$(CONFIG_CPU_IDLE_IBM_POWER) += cpuidle-ibm-power.o
diff --git a/drivers/cpuidle/cpuidle-ibm-power.c b/drivers/cpuidle/cpuidle-ibm-power.c
new file mode 100644
index 0000000..4ee5a94
--- /dev/null
+++ b/drivers/cpuidle/cpuidle-ibm-power.c
@@ -0,0 +1,304 @@
+/*
+ * cpuidle-ibm-power - idle state cpuidle driver.
+ * Adapted from drivers/idle/intel_idle.c and
+ * drivers/acpi/processor_idle.c
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/moduleparam.h>
+#include <linux/cpuidle.h>
+#include <linux/cpu.h>
+#include <linux/notifier.h>
+
+#include <asm/paca.h>
+#include <asm/reg.h>
+#include <asm/machdep.h>
+#include <asm/firmware.h>
+#include <asm/runlatch.h>
+#include <asm/plpar_wrappers.h>
+
+struct cpuidle_driver power_idle_driver = {
+ .name = "IBM-POWER-Idle",
+ .owner = THIS_MODULE,
+};
+
+#define MAX_IDLE_STATE_COUNT 2
+
+static int max_idle_state = MAX_IDLE_STATE_COUNT - 1;
+static struct cpuidle_state *cpuidle_state_table;
+
+static inline void idle_loop_prolog(unsigned long *in_purr)
+{
+ *in_purr = mfspr(SPRN_PURR);
+ /*
+ * Indicate to the HV that we are idle. Now would be
+ * a good time to find other work to dispatch.
+ */
+ get_lppaca()->idle = 1;
+}
+
+static inline void idle_loop_epilog(unsigned long in_purr)
+{
+ get_lppaca()->wait_state_cycles += mfspr(SPRN_PURR) - in_purr;
+ get_lppaca()->idle = 0;
+}
+
+static int snooze_loop(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv,
+ int index)
+{
+ unsigned long in_purr;
+
+ idle_loop_prolog(&in_purr);
+ local_irq_enable();
+ set_thread_flag(TIF_POLLING_NRFLAG);
+
+ while (!need_resched()) {
+ ppc64_runlatch_off();
+ HMT_low();
+ HMT_very_low();
+ }
+
+ HMT_medium();
+ clear_thread_flag(TIF_POLLING_NRFLAG);
+ smp_mb();
+
+ idle_loop_epilog(in_purr);
+
+ return index;
+}
+
+static void check_and_cede_processor(void)
+{
+ /*
+ * Ensure our interrupt state is properly tracked,
+ * also checks if no interrupt has occurred while we
+ * were soft-disabled
+ */
+ if (prep_irq_for_idle()) {
+ cede_processor();
+#ifdef CONFIG_TRACE_IRQFLAGS
+ /* Ensure that H_CEDE returns with IRQs on */
+ if (WARN_ON(!(mfmsr() & MSR_EE)))
+ __hard_irq_enable();
+#endif
+ }
+}
+
+static int dedicated_cede_loop(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv,
+ int index)
+{
+ unsigned long in_purr;
+
+ idle_loop_prolog(&in_purr);
+ get_lppaca()->donate_dedicated_cpu = 1;
+
+ ppc64_runlatch_off();
+ HMT_medium();
+ check_and_cede_processor();
+
+ get_lppaca()->donate_dedicated_cpu = 0;
+ idle_loop_epilog(in_purr);
+
+ return index;
+}
+
+static int shared_cede_loop(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv,
+ int index)
+{
+ unsigned long in_purr;
+
+ idle_loop_prolog(&in_purr);
+
+ /*
+ * Yield the processor to the hypervisor. We return if
+ * an external interrupt occurs (which are driven prior
+ * to returning here) or if a prod occurs from another
+ * processor. When returning here, external interrupts
+ * are enabled.
+ */
+ check_and_cede_processor();
+
+ idle_loop_epilog(in_purr);
+
+ return index;
+}
+
+/*
+ * States for dedicated partition case.
+ */
+static struct cpuidle_state dedicated_states[MAX_IDLE_STATE_COUNT] = {
+ { /* Snooze */
+ .name = "snooze",
+ .desc = "snooze",
+ .flags = CPUIDLE_FLAG_TIME_VALID,
+ .exit_latency = 0,
+ .target_residency = 0,
+ .enter = &snooze_loop },
+ { /* CEDE */
+ .name = "CEDE",
+ .desc = "CEDE",
+ .flags = CPUIDLE_FLAG_TIME_VALID,
+ .exit_latency = 10,
+ .target_residency = 100,
+ .enter = &dedicated_cede_loop },
+};
+
+/*
+ * States for shared partition case.
+ */
+static struct cpuidle_state shared_states[MAX_IDLE_STATE_COUNT] = {
+ { /* Shared Cede */
+ .name = "Shared Cede",
+ .desc = "Shared Cede",
+ .flags = CPUIDLE_FLAG_TIME_VALID,
+ .exit_latency = 0,
+ .target_residency = 0,
+ .enter = &shared_cede_loop },
+};
+
+void update_smt_snooze_delay(int cpu, int residency)
+{
+ struct cpuidle_driver *drv = cpuidle_get_driver();
+ struct cpuidle_device *dev = per_cpu(cpuidle_devices, cpu);
+
+ if (cpuidle_state_table != dedicated_states)
+ return;
+
+ if (residency < 0) {
+ /* Disable the Nap state on that cpu */
+ if (dev)
+ dev->states_usage[1].disable = 1;
+ } else
+ if (drv)
+ drv->states[1].target_residency = residency;
+}
+
+static int power_cpuidle_add_cpu_notifier(struct notifier_block *n,
+ unsigned long action, void *hcpu)
+{
+ int hotcpu = (unsigned long)hcpu;
+ struct cpuidle_device *dev =
+ per_cpu_ptr(cpuidle_devices, hotcpu);
+
+ if (dev && cpuidle_get_driver()) {
+ switch (action) {
+ case CPU_ONLINE:
+ case CPU_ONLINE_FROZEN:
+ cpuidle_pause_and_lock();
+ cpuidle_enable_device(dev);
+ cpuidle_resume_and_unlock();
+ break;
+
+ case CPU_DEAD:
+ case CPU_DEAD_FROZEN:
+ cpuidle_pause_and_lock();
+ cpuidle_disable_device(dev);
+ cpuidle_resume_and_unlock();
+ break;
+
+ default:
+ return NOTIFY_DONE;
+ }
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block setup_hotplug_notifier = {
+ .notifier_call = power_cpuidle_add_cpu_notifier,
+};
+
+/*
+ * power_cpuidle_driver_init()
+ */
+static int power_cpuidle_driver_init(void)
+{
+ int idle_state;
+ struct cpuidle_driver *drv = &power_idle_driver;
+
+ drv->state_count = 0;
+
+ for (idle_state = 0; idle_state < MAX_IDLE_STATE_COUNT; ++idle_state) {
+
+ if (idle_state > max_idle_state)
+ break;
+
+ /* is the state not enabled? */
+ if (cpuidle_state_table[idle_state].enter == NULL)
+ continue;
+
+ drv->states[drv->state_count] = /* structure copy */
+ cpuidle_state_table[idle_state];
+
+ drv->state_count += 1;
+ }
+
+ return 0;
+}
+
+/*
+ * power_idle_probe()
+ * Choose state table for shared versus dedicated partition
+ */
+static int power_idle_probe(void)
+{
+
+ if (cpuidle_disable != IDLE_NO_OVERRIDE)
+ return -ENODEV;
+
+ if (max_idle_state == 0) {
+ printk(KERN_DEBUG "power processor idle disabled.\n");
+ return -EPERM;
+ }
+
+ if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
+ if (get_lppaca()->shared_proc)
+ cpuidle_state_table = shared_states;
+ else
+ cpuidle_state_table = dedicated_states;
+ } else
+ return -ENODEV;
+
+ return 0;
+}
+
+static int __init power_processor_idle_init(void)
+{
+ int retval;
+
+ retval = power_idle_probe();
+ if (retval)
+ return retval;
+
+ power_cpuidle_driver_init();
+ retval = cpuidle_register(&power_idle_driver, NULL);
+ if (retval) {
+ printk(KERN_DEBUG "Registration of power idle driver failed.\n");
+ return retval;
+ }
+
+ register_cpu_notifier(&setup_hotplug_notifier);
+ printk(KERN_DEBUG "power_idle_driver registered\n");
+
+ return 0;
+}
+
+static void __exit power_processor_idle_exit(void)
+{
+
+ unregister_cpu_notifier(&setup_hotplug_notifier);
+ cpuidle_unregister(&power_idle_driver);
+ return;
+}
+
+module_init(power_processor_idle_init);
+module_exit(power_processor_idle_exit);
+
+MODULE_AUTHOR("Deepthi Dharwar <deepthi@xxxxxxxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("Cpuidle driver for IBM POWER platforms");
+MODULE_LICENSE("GPL");
