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-rw-r--r--drivers/cpuidle/Kconfig5
-rw-r--r--drivers/cpuidle/Kconfig.powerpc20
-rw-r--r--drivers/cpuidle/Makefile5
-rw-r--r--drivers/cpuidle/cpuidle-powernv.c169
-rw-r--r--drivers/cpuidle/cpuidle-pseries.c267
5 files changed, 466 insertions, 0 deletions
diff --git a/drivers/cpuidle/Kconfig b/drivers/cpuidle/Kconfig
index b3fb81d7cf0..f04e25f6c98 100644
--- a/drivers/cpuidle/Kconfig
+++ b/drivers/cpuidle/Kconfig
@@ -35,6 +35,11 @@ depends on ARM
source "drivers/cpuidle/Kconfig.arm"
endmenu
+menu "POWERPC CPU Idle Drivers"
+depends on PPC
+source "drivers/cpuidle/Kconfig.powerpc"
+endmenu
+
endif
config ARCH_NEEDS_CPU_IDLE_COUPLED
diff --git a/drivers/cpuidle/Kconfig.powerpc b/drivers/cpuidle/Kconfig.powerpc
new file mode 100644
index 00000000000..66c3a09574e
--- /dev/null
+++ b/drivers/cpuidle/Kconfig.powerpc
@@ -0,0 +1,20 @@
+#
+# POWERPC CPU Idle Drivers
+#
+config PSERIES_CPUIDLE
+ 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.
+
+config POWERNV_CPUIDLE
+ bool "Cpuidle driver for powernv platforms"
+ depends on CPU_IDLE
+ depends on PPC_POWERNV
+ default y
+ help
+ Select this option to enable processor idle state management
+ through cpuidle subsystem.
diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile
index 527be28e5c1..f71ae1b373c 100644
--- a/drivers/cpuidle/Makefile
+++ b/drivers/cpuidle/Makefile
@@ -13,3 +13,8 @@ obj-$(CONFIG_ARM_KIRKWOOD_CPUIDLE) += cpuidle-kirkwood.o
obj-$(CONFIG_ARM_ZYNQ_CPUIDLE) += cpuidle-zynq.o
obj-$(CONFIG_ARM_U8500_CPUIDLE) += cpuidle-ux500.o
obj-$(CONFIG_ARM_AT91_CPUIDLE) += cpuidle-at91.o
+
+###############################################################################
+# POWERPC drivers
+obj-$(CONFIG_PSERIES_CPUIDLE) += cpuidle-pseries.o
+obj-$(CONFIG_POWERNV_CPUIDLE) += cpuidle-powernv.o
diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c
new file mode 100644
index 00000000000..78fd174c57e
--- /dev/null
+++ b/drivers/cpuidle/cpuidle-powernv.c
@@ -0,0 +1,169 @@
+/*
+ * cpuidle-powernv - idle state cpuidle driver.
+ * Adapted from drivers/cpuidle/cpuidle-pseries
+ *
+ */
+
+#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/machdep.h>
+#include <asm/firmware.h>
+
+struct cpuidle_driver powernv_idle_driver = {
+ .name = "powernv_idle",
+ .owner = THIS_MODULE,
+};
+
+static int max_idle_state;
+static struct cpuidle_state *cpuidle_state_table;
+
+static int snooze_loop(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv,
+ int index)
+{
+ local_irq_enable();
+ set_thread_flag(TIF_POLLING_NRFLAG);
+
+ while (!need_resched()) {
+ HMT_low();
+ HMT_very_low();
+ }
+
+ HMT_medium();
+ clear_thread_flag(TIF_POLLING_NRFLAG);
+ smp_mb();
+ return index;
+}
+
+static int nap_loop(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv,
+ int index)
+{
+ power7_idle();
+ return index;
+}
+
+/*
+ * States for dedicated partition case.
+ */
+static struct cpuidle_state powernv_states[] = {
+ { /* Snooze */
+ .name = "snooze",
+ .desc = "snooze",
+ .flags = CPUIDLE_FLAG_TIME_VALID,
+ .exit_latency = 0,
+ .target_residency = 0,
+ .enter = &snooze_loop },
+ { /* NAP */
+ .name = "NAP",
+ .desc = "NAP",
+ .flags = CPUIDLE_FLAG_TIME_VALID,
+ .exit_latency = 10,
+ .target_residency = 100,
+ .enter = &nap_loop },
+};
+
+static int powernv_cpuidle_add_cpu_notifier(struct notifier_block *n,
+ unsigned long action, void *hcpu)
+{
+ int hotcpu = (unsigned long)hcpu;
+ struct cpuidle_device *dev =
+ per_cpu(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 = powernv_cpuidle_add_cpu_notifier,
+};
+
+/*
+ * powernv_cpuidle_driver_init()
+ */
+static int powernv_cpuidle_driver_init(void)
+{
+ int idle_state;
+ struct cpuidle_driver *drv = &powernv_idle_driver;
+
+ drv->state_count = 0;
+
+ for (idle_state = 0; idle_state < max_idle_state; ++idle_state) {
+ /* 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;
+}
+
+/*
+ * powernv_idle_probe()
+ * Choose state table for shared versus dedicated partition
+ */
+static int powernv_idle_probe(void)
+{
+
+ if (cpuidle_disable != IDLE_NO_OVERRIDE)
+ return -ENODEV;
+
+ if (firmware_has_feature(FW_FEATURE_OPALv3)) {
+ cpuidle_state_table = powernv_states;
+ max_idle_state = ARRAY_SIZE(powernv_states);
+ } else
+ return -ENODEV;
+
+ return 0;
+}
+
+static int __init powernv_processor_idle_init(void)
+{
+ int retval;
+
+ retval = powernv_idle_probe();
+ if (retval)
+ return retval;
+
+ powernv_cpuidle_driver_init();
+ retval = cpuidle_register(&powernv_idle_driver, NULL);
+ if (retval) {
+ printk(KERN_DEBUG "Registration of powernv driver failed.\n");
+ return retval;
+ }
+
+ register_cpu_notifier(&setup_hotplug_notifier);
+ printk(KERN_DEBUG "powernv_idle_driver registered\n");
+ return 0;
+}
+
+device_initcall(powernv_processor_idle_init);
diff --git a/drivers/cpuidle/cpuidle-pseries.c b/drivers/cpuidle/cpuidle-pseries.c
new file mode 100644
index 00000000000..7ab564aa0b1
--- /dev/null
+++ b/drivers/cpuidle/cpuidle-pseries.c
@@ -0,0 +1,267 @@
+/*
+ * cpuidle-pseries - 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/plpar_wrappers.h>
+
+struct cpuidle_driver pseries_idle_driver = {
+ .name = "pseries_idle",
+ .owner = THIS_MODULE,
+};
+
+static int max_idle_state;
+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)
+{
+ u64 wait_cycles;
+
+ wait_cycles = be64_to_cpu(get_lppaca()->wait_state_cycles);
+ wait_cycles += mfspr(SPRN_PURR) - in_purr;
+ get_lppaca()->wait_state_cycles = cpu_to_be64(wait_cycles);
+ 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()) {
+ 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;
+
+ 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[] = {
+ { /* 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[] = {
+ { /* Shared Cede */
+ .name = "Shared Cede",
+ .desc = "Shared Cede",
+ .flags = CPUIDLE_FLAG_TIME_VALID,
+ .exit_latency = 0,
+ .target_residency = 0,
+ .enter = &shared_cede_loop },
+};
+
+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(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; ++idle_state) {
+ /* 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_probe()
+ * Choose state table for shared versus dedicated partition
+ */
+static int pseries_idle_probe(void)
+{
+
+ if (cpuidle_disable != IDLE_NO_OVERRIDE)
+ return -ENODEV;
+
+ if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
+ if (lppaca_shared_proc(get_lppaca())) {
+ cpuidle_state_table = shared_states;
+ max_idle_state = ARRAY_SIZE(shared_states);
+ } else {
+ cpuidle_state_table = dedicated_states;
+ max_idle_state = ARRAY_SIZE(dedicated_states);
+ }
+ } else
+ return -ENODEV;
+
+ 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(&pseries_idle_driver, NULL);
+ if (retval) {
+ printk(KERN_DEBUG "Registration of pseries driver failed.\n");
+ return retval;
+ }
+
+ register_cpu_notifier(&setup_hotplug_notifier);
+ printk(KERN_DEBUG "pseries_idle_driver registered\n");
+ return 0;
+}
+
+device_initcall(pseries_processor_idle_init);
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-11-23 23:50:05 +0000