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Diffstat (limited to 'arch/powerpc/platforms/pseries/processor_idle.c')
-rw-r--r--arch/powerpc/platforms/pseries/processor_idle.c364
1 files changed, 0 insertions, 364 deletions
diff --git a/arch/powerpc/platforms/pseries/processor_idle.c b/arch/powerpc/platforms/pseries/processor_idle.c
deleted file mode 100644
index a166e38bd683..000000000000
--- a/arch/powerpc/platforms/pseries/processor_idle.c
+++ /dev/null
@@ -1,364 +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)
-{
- 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;
- 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 (lppaca_shared_proc(get_lppaca()))
- 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@linux.vnet.ibm.com>");
-MODULE_DESCRIPTION("Cpuidle driver for POWER");
-MODULE_LICENSE("GPL");