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Diffstat (limited to 'arch/ppc64/kernel/idle.c')
-rw-r--r--arch/ppc64/kernel/idle.c283
1 files changed, 14 insertions, 269 deletions
diff --git a/arch/ppc64/kernel/idle.c b/arch/ppc64/kernel/idle.c
index 08952c7e621..954395d4263 100644
--- a/arch/ppc64/kernel/idle.c
+++ b/arch/ppc64/kernel/idle.c
@@ -20,109 +20,18 @@
#include <linux/kernel.h>
#include <linux/smp.h>
#include <linux/cpu.h>
-#include <linux/module.h>
#include <linux/sysctl.h>
-#include <linux/smp.h>
#include <asm/system.h>
#include <asm/processor.h>
-#include <asm/mmu.h>
#include <asm/cputable.h>
#include <asm/time.h>
-#include <asm/iSeries/HvCall.h>
-#include <asm/iSeries/ItLpQueue.h>
-#include <asm/plpar_wrappers.h>
#include <asm/systemcfg.h>
+#include <asm/machdep.h>
extern void power4_idle(void);
-static int (*idle_loop)(void);
-
-#ifdef CONFIG_PPC_ISERIES
-static unsigned long maxYieldTime = 0;
-static unsigned long minYieldTime = 0xffffffffffffffffUL;
-
-static inline void process_iSeries_events(void)
-{
- asm volatile ("li 0,0x5555; sc" : : : "r0", "r3");
-}
-
-static void yield_shared_processor(void)
-{
- unsigned long tb;
- unsigned long yieldTime;
-
- HvCall_setEnabledInterrupts(HvCall_MaskIPI |
- HvCall_MaskLpEvent |
- HvCall_MaskLpProd |
- HvCall_MaskTimeout);
-
- tb = get_tb();
- /* Compute future tb value when yield should expire */
- HvCall_yieldProcessor(HvCall_YieldTimed, tb+tb_ticks_per_jiffy);
-
- yieldTime = get_tb() - tb;
- if (yieldTime > maxYieldTime)
- maxYieldTime = yieldTime;
-
- if (yieldTime < minYieldTime)
- minYieldTime = yieldTime;
-
- /*
- * The decrementer stops during the yield. Force a fake decrementer
- * here and let the timer_interrupt code sort out the actual time.
- */
- get_paca()->lppaca.int_dword.fields.decr_int = 1;
- process_iSeries_events();
-}
-
-static int iSeries_idle(void)
-{
- struct paca_struct *lpaca;
- long oldval;
-
- /* ensure iSeries run light will be out when idle */
- ppc64_runlatch_off();
-
- lpaca = get_paca();
-
- while (1) {
- if (lpaca->lppaca.shared_proc) {
- if (hvlpevent_is_pending())
- process_iSeries_events();
- if (!need_resched())
- yield_shared_processor();
- } else {
- oldval = test_and_clear_thread_flag(TIF_NEED_RESCHED);
-
- if (!oldval) {
- set_thread_flag(TIF_POLLING_NRFLAG);
-
- while (!need_resched()) {
- HMT_medium();
- if (hvlpevent_is_pending())
- process_iSeries_events();
- HMT_low();
- }
-
- HMT_medium();
- clear_thread_flag(TIF_POLLING_NRFLAG);
- } else {
- set_need_resched();
- }
- }
-
- ppc64_runlatch_on();
- schedule();
- ppc64_runlatch_off();
- }
-
- return 0;
-}
-
-#else
-
-static int default_idle(void)
+int default_idle(void)
{
long oldval;
unsigned int cpu = smp_processor_id();
@@ -134,7 +43,8 @@ static int default_idle(void)
set_thread_flag(TIF_POLLING_NRFLAG);
while (!need_resched() && !cpu_is_offline(cpu)) {
- barrier();
+ ppc64_runlatch_off();
+
/*
* Go into low thread priority and possibly
* low power mode.
@@ -149,6 +59,7 @@ static int default_idle(void)
set_need_resched();
}
+ ppc64_runlatch_on();
schedule();
if (cpu_is_offline(cpu) && system_state == SYSTEM_RUNNING)
cpu_die();
@@ -157,127 +68,19 @@ static int default_idle(void)
return 0;
}
-#ifdef CONFIG_PPC_PSERIES
-
-DECLARE_PER_CPU(unsigned long, smt_snooze_delay);
-
-int dedicated_idle(void)
+int native_idle(void)
{
- long oldval;
- struct paca_struct *lpaca = get_paca(), *ppaca;
- unsigned long start_snooze;
- unsigned long *smt_snooze_delay = &__get_cpu_var(smt_snooze_delay);
- unsigned int cpu = smp_processor_id();
-
- ppaca = &paca[cpu ^ 1];
-
while (1) {
- /*
- * Indicate to the HV that we are idle. Now would be
- * a good time to find other work to dispatch.
- */
- lpaca->lppaca.idle = 1;
-
- oldval = test_and_clear_thread_flag(TIF_NEED_RESCHED);
- if (!oldval) {
- set_thread_flag(TIF_POLLING_NRFLAG);
- start_snooze = __get_tb() +
- *smt_snooze_delay * tb_ticks_per_usec;
- while (!need_resched() && !cpu_is_offline(cpu)) {
- /*
- * Go into low thread priority and possibly
- * low power mode.
- */
- HMT_low();
- HMT_very_low();
-
- if (*smt_snooze_delay == 0 ||
- __get_tb() < start_snooze)
- continue;
-
- HMT_medium();
-
- if (!(ppaca->lppaca.idle)) {
- local_irq_disable();
-
- /*
- * We are about to sleep the thread
- * and so wont be polling any
- * more.
- */
- clear_thread_flag(TIF_POLLING_NRFLAG);
-
- /*
- * SMT dynamic mode. Cede will result
- * in this thread going dormant, if the
- * partner thread is still doing work.
- * Thread wakes up if partner goes idle,
- * an interrupt is presented, or a prod
- * occurs. Returning from the cede
- * enables external interrupts.
- */
- if (!need_resched())
- cede_processor();
- else
- local_irq_enable();
- } else {
- /*
- * Give the HV an opportunity at the
- * processor, since we are not doing
- * any work.
- */
- poll_pending();
- }
- }
-
- clear_thread_flag(TIF_POLLING_NRFLAG);
- } else {
- set_need_resched();
- }
-
- HMT_medium();
- lpaca->lppaca.idle = 0;
- schedule();
- if (cpu_is_offline(cpu) && system_state == SYSTEM_RUNNING)
- cpu_die();
- }
- return 0;
-}
-
-static int shared_idle(void)
-{
- struct paca_struct *lpaca = get_paca();
- unsigned int cpu = smp_processor_id();
-
- while (1) {
- /*
- * Indicate to the HV that we are idle. Now would be
- * a good time to find other work to dispatch.
- */
- lpaca->lppaca.idle = 1;
+ ppc64_runlatch_off();
- while (!need_resched() && !cpu_is_offline(cpu)) {
- local_irq_disable();
+ if (!need_resched())
+ power4_idle();
- /*
- * 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 need_resched() again with interrupts disabled
- * to avoid a race.
- */
- if (!need_resched())
- cede_processor();
- else
- local_irq_enable();
+ if (need_resched()) {
+ ppc64_runlatch_on();
+ schedule();
}
- HMT_medium();
- lpaca->lppaca.idle = 0;
- schedule();
if (cpu_is_offline(smp_processor_id()) &&
system_state == SYSTEM_RUNNING)
cpu_die();
@@ -286,29 +89,10 @@ static int shared_idle(void)
return 0;
}
-#endif /* CONFIG_PPC_PSERIES */
-
-static int native_idle(void)
-{
- while(1) {
- /* check CPU type here */
- if (!need_resched())
- power4_idle();
- if (need_resched())
- schedule();
-
- if (cpu_is_offline(raw_smp_processor_id()) &&
- system_state == SYSTEM_RUNNING)
- cpu_die();
- }
- return 0;
-}
-
-#endif /* CONFIG_PPC_ISERIES */
-
void cpu_idle(void)
{
- idle_loop();
+ BUG_ON(NULL == ppc_md.idle_loop);
+ ppc_md.idle_loop();
}
int powersave_nap;
@@ -342,42 +126,3 @@ register_powersave_nap_sysctl(void)
}
__initcall(register_powersave_nap_sysctl);
#endif
-
-int idle_setup(void)
-{
- /*
- * Move that junk to each platform specific file, eventually define
- * a pSeries_idle for shared processor stuff
- */
-#ifdef CONFIG_PPC_ISERIES
- idle_loop = iSeries_idle;
- return 1;
-#else
- idle_loop = default_idle;
-#endif
-#ifdef CONFIG_PPC_PSERIES
- if (systemcfg->platform & PLATFORM_PSERIES) {
- if (cur_cpu_spec->firmware_features & FW_FEATURE_SPLPAR) {
- if (get_paca()->lppaca.shared_proc) {
- printk(KERN_INFO "Using shared processor idle loop\n");
- idle_loop = shared_idle;
- } else {
- printk(KERN_INFO "Using dedicated idle loop\n");
- idle_loop = dedicated_idle;
- }
- } else {
- printk(KERN_INFO "Using default idle loop\n");
- idle_loop = default_idle;
- }
- }
-#endif /* CONFIG_PPC_PSERIES */
-#ifndef CONFIG_PPC_ISERIES
- if (systemcfg->platform == PLATFORM_POWERMAC ||
- systemcfg->platform == PLATFORM_MAPLE) {
- printk(KERN_INFO "Using native/NAP idle loop\n");
- idle_loop = native_idle;
- }
-#endif /* CONFIG_PPC_ISERIES */
-
- return 1;
-}
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