diff options
Diffstat (limited to 'arch/ppc64/kernel/idle.c')
-rw-r--r-- | arch/ppc64/kernel/idle.c | 283 |
1 files changed, 14 insertions, 269 deletions
diff --git a/arch/ppc64/kernel/idle.c b/arch/ppc64/kernel/idle.c index 08952c7e6216..954395d42636 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; -} |