From 2201f994a5742c03e660623c385fd6897dd1fa2f Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Tue, 13 Jun 2017 23:05:45 +1000 Subject: [PATCH] powerpc/64s/idle: Move soft interrupt mask logic into C code This simplifies the asm and fixes irq-off tracing over sleep instructions. Also move powersave_nap check for POWER8 into C code, and move PSSCR register value calculation for POWER9 into C. Reviewed-by: Gautham R. Shenoy Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/hw_irq.h | 3 + arch/powerpc/include/asm/machdep.h | 1 + arch/powerpc/include/asm/processor.h | 10 +-- arch/powerpc/kernel/idle_book3s.S | 82 +++++------------------- arch/powerpc/kernel/irq.c | 33 +++++++++- arch/powerpc/platforms/powernv/idle.c | 71 ++++++++++++++++++-- arch/powerpc/platforms/powernv/smp.c | 2 - arch/powerpc/platforms/powernv/subcore.c | 3 +- drivers/cpuidle/cpuidle-powernv.c | 12 ++-- 9 files changed, 128 insertions(+), 89 deletions(-) diff --git a/arch/powerpc/include/asm/hw_irq.h b/arch/powerpc/include/asm/hw_irq.h index eba60416536e..f06112cf8734 100644 --- a/arch/powerpc/include/asm/hw_irq.h +++ b/arch/powerpc/include/asm/hw_irq.h @@ -129,6 +129,9 @@ static inline bool arch_irq_disabled_regs(struct pt_regs *regs) } extern bool prep_irq_for_idle(void); +extern bool prep_irq_for_idle_irqsoff(void); + +#define fini_irq_for_idle_irqsoff() trace_hardirqs_off(); extern void force_external_irq_replay(void); diff --git a/arch/powerpc/include/asm/machdep.h b/arch/powerpc/include/asm/machdep.h index f90b22c722e1..cd2fc1cc1cc7 100644 --- a/arch/powerpc/include/asm/machdep.h +++ b/arch/powerpc/include/asm/machdep.h @@ -226,6 +226,7 @@ struct machdep_calls { extern void e500_idle(void); extern void power4_idle(void); extern void power7_idle(void); +extern void power9_idle(void); extern void ppc6xx_idle(void); extern void book3e_idle(void); diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h index a2123f291ab0..c49165a7439c 100644 --- a/arch/powerpc/include/asm/processor.h +++ b/arch/powerpc/include/asm/processor.h @@ -481,11 +481,11 @@ extern unsigned long cpuidle_disable; 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 unsigned long power7_nap(int check_irq); -extern unsigned long power7_sleep(void); -extern unsigned long power7_winkle(void); -extern unsigned long power9_idle_stop(unsigned long stop_psscr_val, - unsigned long stop_psscr_mask); +extern unsigned long power7_idle_insn(unsigned long type); /* PNV_THREAD_NAP/etc*/ +extern void power7_idle_type(unsigned long type); +extern unsigned long power9_idle_stop(unsigned long psscr_val); +extern void power9_idle_type(unsigned long stop_psscr_val, + unsigned long stop_psscr_mask); extern void flush_instruction_cache(void); extern void hard_reset_now(void); diff --git a/arch/powerpc/kernel/idle_book3s.S b/arch/powerpc/kernel/idle_book3s.S index 98a6d07ecb5c..35cf5bb7daed 100644 --- a/arch/powerpc/kernel/idle_book3s.S +++ b/arch/powerpc/kernel/idle_book3s.S @@ -109,13 +109,9 @@ core_idle_lock_held: /* * Pass requested state in r3: * r3 - PNV_THREAD_NAP/SLEEP/WINKLE in POWER8 - * - Requested STOP state in POWER9 + * - Requested PSSCR value in POWER9 * - * To check IRQ_HAPPENED in r4 - * 0 - don't check - * 1 - check - * - * Address to 'rfid' to in r5 + * Address of idle handler to 'rfid' to in r4 */ pnv_powersave_common: /* Use r3 to pass state nap/sleep/winkle */ @@ -131,30 +127,7 @@ pnv_powersave_common: std r0,_LINK(r1) std r0,_NIP(r1) - /* Hard disable interrupts */ - mfmsr r9 - rldicl r9,r9,48,1 - rotldi r9,r9,16 - mtmsrd r9,1 /* hard-disable interrupts */ - - /* Check if something happened while soft-disabled */ - lbz r0,PACAIRQHAPPENED(r13) - andi. r0,r0,~PACA_IRQ_HARD_DIS@l - beq 1f - cmpwi cr0,r4,0 - beq 1f - addi r1,r1,INT_FRAME_SIZE - ld r0,16(r1) - li r3,0 /* Return 0 (no nap) */ - mtlr r0 - blr - -1: /* We mark irqs hard disabled as this is the state we'll - * be in when returning and we need to tell arch_local_irq_restore() - * about it - */ - li r0,PACA_IRQ_HARD_DIS - stb r0,PACAIRQHAPPENED(r13) + mfmsr r9 /* We haven't lost state ... yet */ li r0,0 @@ -163,8 +136,8 @@ pnv_powersave_common: /* Continue saving state */ SAVE_GPR(2, r1) SAVE_NVGPRS(r1) - mfcr r4 - std r4,_CCR(r1) + mfcr r5 + std r5,_CCR(r1) std r9,_MSR(r1) std r1,PACAR1(r13) @@ -178,7 +151,7 @@ pnv_powersave_common: li r6, MSR_RI andc r6, r9, r6 mtmsrd r6, 1 /* clear RI before setting SRR0/1 */ - mtspr SPRN_SRR0, r5 + mtspr SPRN_SRR0, r4 mtspr SPRN_SRR1, r7 rfid @@ -322,35 +295,14 @@ lwarx_loop_stop: IDLE_STATE_ENTER_SEQ_NORET(PPC_STOP) -_GLOBAL(power7_idle) +/* + * Entered with MSR[EE]=0 and no soft-masked interrupts pending. + * r3 contains desired idle state (PNV_THREAD_NAP/SLEEP/WINKLE). + */ +_GLOBAL(power7_idle_insn) /* Now check if user or arch enabled NAP mode */ - LOAD_REG_ADDRBASE(r3,powersave_nap) - lwz r4,ADDROFF(powersave_nap)(r3) - cmpwi 0,r4,0 - beqlr - li r3, 1 - /* fall through */ - -_GLOBAL(power7_nap) - mr r4,r3 - li r3,PNV_THREAD_NAP - LOAD_REG_ADDR(r5, pnv_enter_arch207_idle_mode) - b pnv_powersave_common - /* No return */ - -_GLOBAL(power7_sleep) - li r3,PNV_THREAD_SLEEP - li r4,1 - LOAD_REG_ADDR(r5, pnv_enter_arch207_idle_mode) + LOAD_REG_ADDR(r4, pnv_enter_arch207_idle_mode) b pnv_powersave_common - /* No return */ - -_GLOBAL(power7_winkle) - li r3,PNV_THREAD_WINKLE - li r4,1 - LOAD_REG_ADDR(r5, pnv_enter_arch207_idle_mode) - b pnv_powersave_common - /* No return */ #define CHECK_HMI_INTERRUPT \ mfspr r0,SPRN_SRR1; \ @@ -372,17 +324,13 @@ ALT_FTR_SECTION_END_NESTED_IFSET(CPU_FTR_ARCH_207S, 66); \ 20: nop; /* - * r3 - The PSSCR value corresponding to the stop state. - * r4 - The PSSCR mask corrresonding to the stop state. + * Entered with MSR[EE]=0 and no soft-masked interrupts pending. + * r3 contains desired PSSCR register value. */ _GLOBAL(power9_idle_stop) - mfspr r5,SPRN_PSSCR - andc r5,r5,r4 - or r3,r3,r5 std r3, PACA_REQ_PSSCR(r13) mtspr SPRN_PSSCR,r3 - LOAD_REG_ADDR(r5,power_enter_stop) - li r4,1 + LOAD_REG_ADDR(r4,power_enter_stop) b pnv_powersave_common /* No return */ diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c index 5c291df30fe3..58dcac88bc79 100644 --- a/arch/powerpc/kernel/irq.c +++ b/arch/powerpc/kernel/irq.c @@ -322,7 +322,8 @@ bool prep_irq_for_idle(void) * First we need to hard disable to ensure no interrupt * occurs before we effectively enter the low power state */ - hard_irq_disable(); + __hard_irq_disable(); + local_paca->irq_happened |= PACA_IRQ_HARD_DIS; /* * If anything happened while we were soft-disabled, @@ -347,6 +348,36 @@ bool prep_irq_for_idle(void) return true; } +/* + * This is for idle sequences that return with IRQs off, but the + * idle state itself wakes on interrupt. Tell the irq tracer that + * IRQs are enabled for the duration of idle so it does not get long + * off times. Must be paired with fini_irq_for_idle_irqsoff. + */ +bool prep_irq_for_idle_irqsoff(void) +{ + WARN_ON(!irqs_disabled()); + + /* + * First we need to hard disable to ensure no interrupt + * occurs before we effectively enter the low power state + */ + __hard_irq_disable(); + local_paca->irq_happened |= PACA_IRQ_HARD_DIS; + + /* + * If anything happened while we were soft-disabled, + * we return now and do not enter the low power state. + */ + if (lazy_irq_pending()) + return false; + + /* Tell lockdep we are about to re-enable */ + trace_hardirqs_on(); + + return true; +} + /* * Force a replay of the external interrupt handler on this CPU. */ diff --git a/arch/powerpc/platforms/powernv/idle.c b/arch/powerpc/platforms/powernv/idle.c index 46946a587004..f875879ff1eb 100644 --- a/arch/powerpc/platforms/powernv/idle.c +++ b/arch/powerpc/platforms/powernv/idle.c @@ -23,6 +23,7 @@ #include #include #include +#include #include "powernv.h" #include "subcore.h" @@ -283,12 +284,68 @@ static DEVICE_ATTR(fastsleep_workaround_applyonce, 0600, show_fastsleep_workaround_applyonce, store_fastsleep_workaround_applyonce); +static unsigned long __power7_idle_type(unsigned long type) +{ + unsigned long srr1; + + if (!prep_irq_for_idle_irqsoff()) + return 0; + + ppc64_runlatch_off(); + srr1 = power7_idle_insn(type); + ppc64_runlatch_on(); + + fini_irq_for_idle_irqsoff(); + + return srr1; +} + +void power7_idle_type(unsigned long type) +{ + __power7_idle_type(type); +} + +void power7_idle(void) +{ + if (!powersave_nap) + return; + + power7_idle_type(PNV_THREAD_NAP); +} + +static unsigned long __power9_idle_type(unsigned long stop_psscr_val, + unsigned long stop_psscr_mask) +{ + unsigned long psscr; + unsigned long srr1; + + if (!prep_irq_for_idle_irqsoff()) + return 0; + + psscr = mfspr(SPRN_PSSCR); + psscr = (psscr & ~stop_psscr_mask) | stop_psscr_val; + + ppc64_runlatch_off(); + srr1 = power9_idle_stop(psscr); + ppc64_runlatch_on(); + + fini_irq_for_idle_irqsoff(); + + return srr1; +} + +void power9_idle_type(unsigned long stop_psscr_val, + unsigned long stop_psscr_mask) +{ + __power9_idle_type(stop_psscr_val, stop_psscr_mask); +} + /* * Used for ppc_md.power_save which needs a function with no parameters */ -static void power9_idle(void) +void power9_idle(void) { - power9_idle_stop(pnv_default_stop_val, pnv_default_stop_mask); + power9_idle_type(pnv_default_stop_val, pnv_default_stop_mask); } #ifdef CONFIG_HOTPLUG_CPU @@ -303,16 +360,17 @@ unsigned long pnv_cpu_offline(unsigned int cpu) u32 idle_states = pnv_get_supported_cpuidle_states(); if (cpu_has_feature(CPU_FTR_ARCH_300) && deepest_stop_found) { - srr1 = power9_idle_stop(pnv_deepest_stop_psscr_val, + srr1 = __power9_idle_type(pnv_deepest_stop_psscr_val, pnv_deepest_stop_psscr_mask); } else if (idle_states & OPAL_PM_WINKLE_ENABLED) { - srr1 = power7_winkle(); + srr1 = __power7_idle_type(PNV_THREAD_WINKLE); } else if ((idle_states & OPAL_PM_SLEEP_ENABLED) || (idle_states & OPAL_PM_SLEEP_ENABLED_ER1)) { - srr1 = power7_sleep(); + srr1 = __power7_idle_type(PNV_THREAD_SLEEP); } else if (idle_states & OPAL_PM_NAP_ENABLED) { - srr1 = power7_nap(1); + srr1 = __power7_idle_type(PNV_THREAD_NAP); } else { + ppc64_runlatch_off(); /* This is the fallback method. We emulate snooze */ while (!generic_check_cpu_restart(cpu)) { HMT_low(); @@ -320,6 +378,7 @@ unsigned long pnv_cpu_offline(unsigned int cpu) } srr1 = 0; HMT_medium(); + ppc64_runlatch_on(); } return srr1; diff --git a/arch/powerpc/platforms/powernv/smp.c b/arch/powerpc/platforms/powernv/smp.c index 4aff754b6f2c..f8752795decf 100644 --- a/arch/powerpc/platforms/powernv/smp.c +++ b/arch/powerpc/platforms/powernv/smp.c @@ -182,9 +182,7 @@ static void pnv_smp_cpu_kill_self(void) */ kvmppc_set_host_ipi(cpu, 0); - ppc64_runlatch_off(); srr1 = pnv_cpu_offline(cpu); - ppc64_runlatch_on(); /* * If the SRR1 value indicates that we woke up due to diff --git a/arch/powerpc/platforms/powernv/subcore.c b/arch/powerpc/platforms/powernv/subcore.c index 0babef11136f..d975d78188a9 100644 --- a/arch/powerpc/platforms/powernv/subcore.c +++ b/arch/powerpc/platforms/powernv/subcore.c @@ -18,6 +18,7 @@ #include #include +#include #include #include #include @@ -182,7 +183,7 @@ static void unsplit_core(void) cpu = smp_processor_id(); if (cpu_thread_in_core(cpu) != 0) { while (mfspr(SPRN_HID0) & mask) - power7_nap(0); + power7_idle_insn(PNV_THREAD_NAP); per_cpu(split_state, cpu).step = SYNC_STEP_UNSPLIT; return; diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c index 45eaf06462ae..79152676f62b 100644 --- a/drivers/cpuidle/cpuidle-powernv.c +++ b/drivers/cpuidle/cpuidle-powernv.c @@ -73,9 +73,8 @@ static int nap_loop(struct cpuidle_device *dev, struct cpuidle_driver *drv, int index) { - ppc64_runlatch_off(); - power7_idle(); - ppc64_runlatch_on(); + power7_idle_type(PNV_THREAD_NAP); + return index; } @@ -98,7 +97,8 @@ static int fastsleep_loop(struct cpuidle_device *dev, new_lpcr &= ~LPCR_PECE1; mtspr(SPRN_LPCR, new_lpcr); - power7_sleep(); + + power7_idle_type(PNV_THREAD_SLEEP); mtspr(SPRN_LPCR, old_lpcr); @@ -110,10 +110,8 @@ static int stop_loop(struct cpuidle_device *dev, struct cpuidle_driver *drv, int index) { - ppc64_runlatch_off(); - power9_idle_stop(stop_psscr_table[index].val, + power9_idle_type(stop_psscr_table[index].val, stop_psscr_table[index].mask); - ppc64_runlatch_on(); return index; } -- GitLab