| // SPDX-License-Identifier: GPL-2.0-or-later |
| /* |
| * PowerNV cpuidle code |
| * |
| * Copyright 2015 IBM Corp. |
| */ |
| |
| #include <linux/types.h> |
| #include <linux/mm.h> |
| #include <linux/slab.h> |
| #include <linux/of.h> |
| #include <linux/device.h> |
| #include <linux/cpu.h> |
| |
| #include <asm/asm-prototypes.h> |
| #include <asm/firmware.h> |
| #include <asm/interrupt.h> |
| #include <asm/machdep.h> |
| #include <asm/opal.h> |
| #include <asm/cputhreads.h> |
| #include <asm/cpuidle.h> |
| #include <asm/code-patching.h> |
| #include <asm/smp.h> |
| #include <asm/runlatch.h> |
| #include <asm/dbell.h> |
| |
| #include "powernv.h" |
| #include "subcore.h" |
| |
| /* Power ISA 3.0 allows for stop states 0x0 - 0xF */ |
| #define MAX_STOP_STATE 0xF |
| |
| #define P9_STOP_SPR_MSR 2000 |
| #define P9_STOP_SPR_PSSCR 855 |
| |
| static u32 supported_cpuidle_states; |
| struct pnv_idle_states_t *pnv_idle_states; |
| int nr_pnv_idle_states; |
| |
| /* |
| * The default stop state that will be used by ppc_md.power_save |
| * function on platforms that support stop instruction. |
| */ |
| static u64 pnv_default_stop_val; |
| static u64 pnv_default_stop_mask; |
| static bool default_stop_found; |
| |
| /* |
| * First stop state levels when SPR and TB loss can occur. |
| */ |
| static u64 pnv_first_tb_loss_level = MAX_STOP_STATE + 1; |
| static u64 deep_spr_loss_state = MAX_STOP_STATE + 1; |
| |
| /* |
| * psscr value and mask of the deepest stop idle state. |
| * Used when a cpu is offlined. |
| */ |
| static u64 pnv_deepest_stop_psscr_val; |
| static u64 pnv_deepest_stop_psscr_mask; |
| static u64 pnv_deepest_stop_flag; |
| static bool deepest_stop_found; |
| |
| static unsigned long power7_offline_type; |
| |
| static int pnv_save_sprs_for_deep_states(void) |
| { |
| int cpu; |
| int rc; |
| |
| /* |
| * hid0, hid1, hid4, hid5, hmeer and lpcr values are symmetric across |
| * all cpus at boot. Get these reg values of current cpu and use the |
| * same across all cpus. |
| */ |
| uint64_t lpcr_val = mfspr(SPRN_LPCR); |
| uint64_t hid0_val = mfspr(SPRN_HID0); |
| uint64_t hmeer_val = mfspr(SPRN_HMEER); |
| uint64_t msr_val = MSR_IDLE; |
| uint64_t psscr_val = pnv_deepest_stop_psscr_val; |
| |
| for_each_present_cpu(cpu) { |
| uint64_t pir = get_hard_smp_processor_id(cpu); |
| uint64_t hsprg0_val = (uint64_t)paca_ptrs[cpu]; |
| |
| rc = opal_slw_set_reg(pir, SPRN_HSPRG0, hsprg0_val); |
| if (rc != 0) |
| return rc; |
| |
| rc = opal_slw_set_reg(pir, SPRN_LPCR, lpcr_val); |
| if (rc != 0) |
| return rc; |
| |
| if (cpu_has_feature(CPU_FTR_ARCH_300)) { |
| rc = opal_slw_set_reg(pir, P9_STOP_SPR_MSR, msr_val); |
| if (rc) |
| return rc; |
| |
| rc = opal_slw_set_reg(pir, |
| P9_STOP_SPR_PSSCR, psscr_val); |
| |
| if (rc) |
| return rc; |
| } |
| |
| /* HIDs are per core registers */ |
| if (cpu_thread_in_core(cpu) == 0) { |
| |
| rc = opal_slw_set_reg(pir, SPRN_HMEER, hmeer_val); |
| if (rc != 0) |
| return rc; |
| |
| rc = opal_slw_set_reg(pir, SPRN_HID0, hid0_val); |
| if (rc != 0) |
| return rc; |
| |
| /* Only p8 needs to set extra HID regiters */ |
| if (!cpu_has_feature(CPU_FTR_ARCH_300)) { |
| uint64_t hid1_val = mfspr(SPRN_HID1); |
| uint64_t hid4_val = mfspr(SPRN_HID4); |
| uint64_t hid5_val = mfspr(SPRN_HID5); |
| |
| rc = opal_slw_set_reg(pir, SPRN_HID1, hid1_val); |
| if (rc != 0) |
| return rc; |
| |
| rc = opal_slw_set_reg(pir, SPRN_HID4, hid4_val); |
| if (rc != 0) |
| return rc; |
| |
| rc = opal_slw_set_reg(pir, SPRN_HID5, hid5_val); |
| if (rc != 0) |
| return rc; |
| } |
| } |
| } |
| |
| return 0; |
| } |
| |
| u32 pnv_get_supported_cpuidle_states(void) |
| { |
| return supported_cpuidle_states; |
| } |
| EXPORT_SYMBOL_GPL(pnv_get_supported_cpuidle_states); |
| |
| static void pnv_fastsleep_workaround_apply(void *info) |
| |
| { |
| int rc; |
| int *err = info; |
| |
| rc = opal_config_cpu_idle_state(OPAL_CONFIG_IDLE_FASTSLEEP, |
| OPAL_CONFIG_IDLE_APPLY); |
| if (rc) |
| *err = 1; |
| } |
| |
| static bool power7_fastsleep_workaround_entry = true; |
| static bool power7_fastsleep_workaround_exit = true; |
| |
| /* |
| * Used to store fastsleep workaround state |
| * 0 - Workaround applied/undone at fastsleep entry/exit path (Default) |
| * 1 - Workaround applied once, never undone. |
| */ |
| static u8 fastsleep_workaround_applyonce; |
| |
| static ssize_t show_fastsleep_workaround_applyonce(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| return sprintf(buf, "%u\n", fastsleep_workaround_applyonce); |
| } |
| |
| static ssize_t store_fastsleep_workaround_applyonce(struct device *dev, |
| struct device_attribute *attr, const char *buf, |
| size_t count) |
| { |
| cpumask_t primary_thread_mask; |
| int err; |
| u8 val; |
| |
| if (kstrtou8(buf, 0, &val) || val != 1) |
| return -EINVAL; |
| |
| if (fastsleep_workaround_applyonce == 1) |
| return count; |
| |
| /* |
| * fastsleep_workaround_applyonce = 1 implies |
| * fastsleep workaround needs to be left in 'applied' state on all |
| * the cores. Do this by- |
| * 1. Disable the 'undo' workaround in fastsleep exit path |
| * 2. Sendi IPIs to all the cores which have at least one online thread |
| * 3. Disable the 'apply' workaround in fastsleep entry path |
| * |
| * There is no need to send ipi to cores which have all threads |
| * offlined, as last thread of the core entering fastsleep or deeper |
| * state would have applied workaround. |
| */ |
| power7_fastsleep_workaround_exit = false; |
| |
| cpus_read_lock(); |
| primary_thread_mask = cpu_online_cores_map(); |
| on_each_cpu_mask(&primary_thread_mask, |
| pnv_fastsleep_workaround_apply, |
| &err, 1); |
| cpus_read_unlock(); |
| if (err) { |
| pr_err("fastsleep_workaround_applyonce change failed while running pnv_fastsleep_workaround_apply"); |
| goto fail; |
| } |
| |
| power7_fastsleep_workaround_entry = false; |
| |
| fastsleep_workaround_applyonce = 1; |
| |
| return count; |
| fail: |
| return -EIO; |
| } |
| |
| static DEVICE_ATTR(fastsleep_workaround_applyonce, 0600, |
| show_fastsleep_workaround_applyonce, |
| store_fastsleep_workaround_applyonce); |
| |
| static inline void atomic_start_thread_idle(void) |
| { |
| int cpu = raw_smp_processor_id(); |
| int first = cpu_first_thread_sibling(cpu); |
| int thread_nr = cpu_thread_in_core(cpu); |
| unsigned long *state = &paca_ptrs[first]->idle_state; |
| |
| clear_bit(thread_nr, state); |
| } |
| |
| static inline void atomic_stop_thread_idle(void) |
| { |
| int cpu = raw_smp_processor_id(); |
| int first = cpu_first_thread_sibling(cpu); |
| int thread_nr = cpu_thread_in_core(cpu); |
| unsigned long *state = &paca_ptrs[first]->idle_state; |
| |
| set_bit(thread_nr, state); |
| } |
| |
| static inline void atomic_lock_thread_idle(void) |
| { |
| int cpu = raw_smp_processor_id(); |
| int first = cpu_first_thread_sibling(cpu); |
| unsigned long *state = &paca_ptrs[first]->idle_state; |
| |
| while (unlikely(test_and_set_bit_lock(NR_PNV_CORE_IDLE_LOCK_BIT, state))) |
| barrier(); |
| } |
| |
| static inline void atomic_unlock_and_stop_thread_idle(void) |
| { |
| int cpu = raw_smp_processor_id(); |
| int first = cpu_first_thread_sibling(cpu); |
| unsigned long thread = 1UL << cpu_thread_in_core(cpu); |
| unsigned long *state = &paca_ptrs[first]->idle_state; |
| u64 s = READ_ONCE(*state); |
| u64 new, tmp; |
| |
| BUG_ON(!(s & PNV_CORE_IDLE_LOCK_BIT)); |
| BUG_ON(s & thread); |
| |
| again: |
| new = (s | thread) & ~PNV_CORE_IDLE_LOCK_BIT; |
| tmp = cmpxchg(state, s, new); |
| if (unlikely(tmp != s)) { |
| s = tmp; |
| goto again; |
| } |
| } |
| |
| static inline void atomic_unlock_thread_idle(void) |
| { |
| int cpu = raw_smp_processor_id(); |
| int first = cpu_first_thread_sibling(cpu); |
| unsigned long *state = &paca_ptrs[first]->idle_state; |
| |
| BUG_ON(!test_bit(NR_PNV_CORE_IDLE_LOCK_BIT, state)); |
| clear_bit_unlock(NR_PNV_CORE_IDLE_LOCK_BIT, state); |
| } |
| |
| /* P7 and P8 */ |
| struct p7_sprs { |
| /* per core */ |
| u64 tscr; |
| u64 worc; |
| |
| /* per subcore */ |
| u64 sdr1; |
| u64 rpr; |
| |
| /* per thread */ |
| u64 lpcr; |
| u64 hfscr; |
| u64 fscr; |
| u64 purr; |
| u64 spurr; |
| u64 dscr; |
| u64 wort; |
| |
| /* per thread SPRs that get lost in shallow states */ |
| u64 amr; |
| u64 iamr; |
| u64 amor; |
| u64 uamor; |
| }; |
| |
| static unsigned long power7_idle_insn(unsigned long type) |
| { |
| int cpu = raw_smp_processor_id(); |
| int first = cpu_first_thread_sibling(cpu); |
| unsigned long *state = &paca_ptrs[first]->idle_state; |
| unsigned long thread = 1UL << cpu_thread_in_core(cpu); |
| unsigned long core_thread_mask = (1UL << threads_per_core) - 1; |
| unsigned long srr1; |
| bool full_winkle; |
| struct p7_sprs sprs = {}; /* avoid false use-uninitialised */ |
| bool sprs_saved = false; |
| int rc; |
| |
| if (unlikely(type != PNV_THREAD_NAP)) { |
| atomic_lock_thread_idle(); |
| |
| BUG_ON(!(*state & thread)); |
| *state &= ~thread; |
| |
| if (power7_fastsleep_workaround_entry) { |
| if ((*state & core_thread_mask) == 0) { |
| rc = opal_config_cpu_idle_state( |
| OPAL_CONFIG_IDLE_FASTSLEEP, |
| OPAL_CONFIG_IDLE_APPLY); |
| BUG_ON(rc); |
| } |
| } |
| |
| if (type == PNV_THREAD_WINKLE) { |
| sprs.tscr = mfspr(SPRN_TSCR); |
| sprs.worc = mfspr(SPRN_WORC); |
| |
| sprs.sdr1 = mfspr(SPRN_SDR1); |
| sprs.rpr = mfspr(SPRN_RPR); |
| |
| sprs.lpcr = mfspr(SPRN_LPCR); |
| if (cpu_has_feature(CPU_FTR_ARCH_207S)) { |
| sprs.hfscr = mfspr(SPRN_HFSCR); |
| sprs.fscr = mfspr(SPRN_FSCR); |
| } |
| sprs.purr = mfspr(SPRN_PURR); |
| sprs.spurr = mfspr(SPRN_SPURR); |
| sprs.dscr = mfspr(SPRN_DSCR); |
| sprs.wort = mfspr(SPRN_WORT); |
| |
| sprs_saved = true; |
| |
| /* |
| * Increment winkle counter and set all winkle bits if |
| * all threads are winkling. This allows wakeup side to |
| * distinguish between fast sleep and winkle state |
| * loss. Fast sleep still has to resync the timebase so |
| * this may not be a really big win. |
| */ |
| *state += 1 << PNV_CORE_IDLE_WINKLE_COUNT_SHIFT; |
| if ((*state & PNV_CORE_IDLE_WINKLE_COUNT_BITS) |
| >> PNV_CORE_IDLE_WINKLE_COUNT_SHIFT |
| == threads_per_core) |
| *state |= PNV_CORE_IDLE_THREAD_WINKLE_BITS; |
| WARN_ON((*state & PNV_CORE_IDLE_WINKLE_COUNT_BITS) == 0); |
| } |
| |
| atomic_unlock_thread_idle(); |
| } |
| |
| if (cpu_has_feature(CPU_FTR_ARCH_207S)) { |
| sprs.amr = mfspr(SPRN_AMR); |
| sprs.iamr = mfspr(SPRN_IAMR); |
| sprs.amor = mfspr(SPRN_AMOR); |
| sprs.uamor = mfspr(SPRN_UAMOR); |
| } |
| |
| local_paca->thread_idle_state = type; |
| srr1 = isa206_idle_insn_mayloss(type); /* go idle */ |
| local_paca->thread_idle_state = PNV_THREAD_RUNNING; |
| |
| WARN_ON_ONCE(!srr1); |
| WARN_ON_ONCE(mfmsr() & (MSR_IR|MSR_DR)); |
| |
| if (cpu_has_feature(CPU_FTR_ARCH_207S)) { |
| if ((srr1 & SRR1_WAKESTATE) != SRR1_WS_NOLOSS) { |
| /* |
| * We don't need an isync after the mtsprs here because |
| * the upcoming mtmsrd is execution synchronizing. |
| */ |
| mtspr(SPRN_AMR, sprs.amr); |
| mtspr(SPRN_IAMR, sprs.iamr); |
| mtspr(SPRN_AMOR, sprs.amor); |
| mtspr(SPRN_UAMOR, sprs.uamor); |
| } |
| } |
| |
| if (unlikely((srr1 & SRR1_WAKEMASK_P8) == SRR1_WAKEHMI)) |
| hmi_exception_realmode(NULL); |
| |
| if (likely((srr1 & SRR1_WAKESTATE) != SRR1_WS_HVLOSS)) { |
| if (unlikely(type != PNV_THREAD_NAP)) { |
| atomic_lock_thread_idle(); |
| if (type == PNV_THREAD_WINKLE) { |
| WARN_ON((*state & PNV_CORE_IDLE_WINKLE_COUNT_BITS) == 0); |
| *state -= 1 << PNV_CORE_IDLE_WINKLE_COUNT_SHIFT; |
| *state &= ~(thread << PNV_CORE_IDLE_THREAD_WINKLE_BITS_SHIFT); |
| } |
| atomic_unlock_and_stop_thread_idle(); |
| } |
| return srr1; |
| } |
| |
| /* HV state loss */ |
| BUG_ON(type == PNV_THREAD_NAP); |
| |
| atomic_lock_thread_idle(); |
| |
| full_winkle = false; |
| if (type == PNV_THREAD_WINKLE) { |
| WARN_ON((*state & PNV_CORE_IDLE_WINKLE_COUNT_BITS) == 0); |
| *state -= 1 << PNV_CORE_IDLE_WINKLE_COUNT_SHIFT; |
| if (*state & (thread << PNV_CORE_IDLE_THREAD_WINKLE_BITS_SHIFT)) { |
| *state &= ~(thread << PNV_CORE_IDLE_THREAD_WINKLE_BITS_SHIFT); |
| full_winkle = true; |
| BUG_ON(!sprs_saved); |
| } |
| } |
| |
| WARN_ON(*state & thread); |
| |
| if ((*state & core_thread_mask) != 0) |
| goto core_woken; |
| |
| /* Per-core SPRs */ |
| if (full_winkle) { |
| mtspr(SPRN_TSCR, sprs.tscr); |
| mtspr(SPRN_WORC, sprs.worc); |
| } |
| |
| if (power7_fastsleep_workaround_exit) { |
| rc = opal_config_cpu_idle_state(OPAL_CONFIG_IDLE_FASTSLEEP, |
| OPAL_CONFIG_IDLE_UNDO); |
| BUG_ON(rc); |
| } |
| |
| /* TB */ |
| if (opal_resync_timebase() != OPAL_SUCCESS) |
| BUG(); |
| |
| core_woken: |
| if (!full_winkle) |
| goto subcore_woken; |
| |
| if ((*state & local_paca->subcore_sibling_mask) != 0) |
| goto subcore_woken; |
| |
| /* Per-subcore SPRs */ |
| mtspr(SPRN_SDR1, sprs.sdr1); |
| mtspr(SPRN_RPR, sprs.rpr); |
| |
| subcore_woken: |
| /* |
| * isync after restoring shared SPRs and before unlocking. Unlock |
| * only contains hwsync which does not necessarily do the right |
| * thing for SPRs. |
| */ |
| isync(); |
| atomic_unlock_and_stop_thread_idle(); |
| |
| /* Fast sleep does not lose SPRs */ |
| if (!full_winkle) |
| return srr1; |
| |
| /* Per-thread SPRs */ |
| mtspr(SPRN_LPCR, sprs.lpcr); |
| if (cpu_has_feature(CPU_FTR_ARCH_207S)) { |
| mtspr(SPRN_HFSCR, sprs.hfscr); |
| mtspr(SPRN_FSCR, sprs.fscr); |
| } |
| mtspr(SPRN_PURR, sprs.purr); |
| mtspr(SPRN_SPURR, sprs.spurr); |
| mtspr(SPRN_DSCR, sprs.dscr); |
| mtspr(SPRN_WORT, sprs.wort); |
| |
| mtspr(SPRN_SPRG3, local_paca->sprg_vdso); |
| |
| /* |
| * The SLB has to be restored here, but it sometimes still |
| * contains entries, so the __ variant must be used to prevent |
| * multi hits. |
| */ |
| __slb_restore_bolted_realmode(); |
| |
| return srr1; |
| } |
| |
| extern unsigned long idle_kvm_start_guest(unsigned long srr1); |
| |
| #ifdef CONFIG_HOTPLUG_CPU |
| static unsigned long power7_offline(void) |
| { |
| unsigned long srr1; |
| |
| mtmsr(MSR_IDLE); |
| |
| #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE |
| /* Tell KVM we're entering idle. */ |
| /******************************************************/ |
| /* N O T E W E L L ! ! ! N O T E W E L L */ |
| /* The following store to HSTATE_HWTHREAD_STATE(r13) */ |
| /* MUST occur in real mode, i.e. with the MMU off, */ |
| /* and the MMU must stay off until we clear this flag */ |
| /* and test HSTATE_HWTHREAD_REQ(r13) in */ |
| /* pnv_powersave_wakeup in this file. */ |
| /* The reason is that another thread can switch the */ |
| /* MMU to a guest context whenever this flag is set */ |
| /* to KVM_HWTHREAD_IN_IDLE, and if the MMU was on, */ |
| /* that would potentially cause this thread to start */ |
| /* executing instructions from guest memory in */ |
| /* hypervisor mode, leading to a host crash or data */ |
| /* corruption, or worse. */ |
| /******************************************************/ |
| local_paca->kvm_hstate.hwthread_state = KVM_HWTHREAD_IN_IDLE; |
| #endif |
| |
| __ppc64_runlatch_off(); |
| srr1 = power7_idle_insn(power7_offline_type); |
| __ppc64_runlatch_on(); |
| |
| #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE |
| local_paca->kvm_hstate.hwthread_state = KVM_HWTHREAD_IN_KERNEL; |
| /* Order setting hwthread_state vs. testing hwthread_req */ |
| smp_mb(); |
| if (local_paca->kvm_hstate.hwthread_req) |
| srr1 = idle_kvm_start_guest(srr1); |
| #endif |
| |
| mtmsr(MSR_KERNEL); |
| |
| return srr1; |
| } |
| #endif |
| |
| void power7_idle_type(unsigned long type) |
| { |
| unsigned long srr1; |
| |
| if (!prep_irq_for_idle_irqsoff()) |
| return; |
| |
| mtmsr(MSR_IDLE); |
| __ppc64_runlatch_off(); |
| srr1 = power7_idle_insn(type); |
| __ppc64_runlatch_on(); |
| mtmsr(MSR_KERNEL); |
| |
| fini_irq_for_idle_irqsoff(); |
| irq_set_pending_from_srr1(srr1); |
| } |
| |
| static void power7_idle(void) |
| { |
| if (!powersave_nap) |
| return; |
| |
| power7_idle_type(PNV_THREAD_NAP); |
| } |
| |
| struct p9_sprs { |
| /* per core */ |
| u64 ptcr; |
| u64 rpr; |
| u64 tscr; |
| u64 ldbar; |
| |
| /* per thread */ |
| u64 lpcr; |
| u64 hfscr; |
| u64 fscr; |
| u64 pid; |
| u64 purr; |
| u64 spurr; |
| u64 dscr; |
| u64 wort; |
| u64 ciabr; |
| |
| u64 mmcra; |
| u32 mmcr0; |
| u32 mmcr1; |
| u64 mmcr2; |
| |
| /* per thread SPRs that get lost in shallow states */ |
| u64 amr; |
| u64 iamr; |
| u64 amor; |
| u64 uamor; |
| }; |
| |
| static unsigned long power9_idle_stop(unsigned long psscr) |
| { |
| int cpu = raw_smp_processor_id(); |
| int first = cpu_first_thread_sibling(cpu); |
| unsigned long *state = &paca_ptrs[first]->idle_state; |
| unsigned long core_thread_mask = (1UL << threads_per_core) - 1; |
| unsigned long srr1; |
| unsigned long pls; |
| unsigned long mmcr0 = 0; |
| unsigned long mmcra = 0; |
| struct p9_sprs sprs = {}; /* avoid false used-uninitialised */ |
| bool sprs_saved = false; |
| |
| if (!(psscr & (PSSCR_EC|PSSCR_ESL))) { |
| /* EC=ESL=0 case */ |
| |
| /* |
| * Wake synchronously. SRESET via xscom may still cause |
| * a 0x100 powersave wakeup with SRR1 reason! |
| */ |
| srr1 = isa300_idle_stop_noloss(psscr); /* go idle */ |
| if (likely(!srr1)) |
| return 0; |
| |
| /* |
| * Registers not saved, can't recover! |
| * This would be a hardware bug |
| */ |
| BUG_ON((srr1 & SRR1_WAKESTATE) != SRR1_WS_NOLOSS); |
| |
| goto out; |
| } |
| |
| /* EC=ESL=1 case */ |
| #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE |
| if (cpu_has_feature(CPU_FTR_P9_TM_XER_SO_BUG)) { |
| local_paca->requested_psscr = psscr; |
| /* order setting requested_psscr vs testing dont_stop */ |
| smp_mb(); |
| if (atomic_read(&local_paca->dont_stop)) { |
| local_paca->requested_psscr = 0; |
| return 0; |
| } |
| } |
| #endif |
| |
| if (!cpu_has_feature(CPU_FTR_POWER9_DD2_1)) { |
| /* |
| * POWER9 DD2 can incorrectly set PMAO when waking up |
| * after a state-loss idle. Saving and restoring MMCR0 |
| * over idle is a workaround. |
| */ |
| mmcr0 = mfspr(SPRN_MMCR0); |
| } |
| |
| if ((psscr & PSSCR_RL_MASK) >= deep_spr_loss_state) { |
| sprs.lpcr = mfspr(SPRN_LPCR); |
| sprs.hfscr = mfspr(SPRN_HFSCR); |
| sprs.fscr = mfspr(SPRN_FSCR); |
| sprs.pid = mfspr(SPRN_PID); |
| sprs.purr = mfspr(SPRN_PURR); |
| sprs.spurr = mfspr(SPRN_SPURR); |
| sprs.dscr = mfspr(SPRN_DSCR); |
| sprs.ciabr = mfspr(SPRN_CIABR); |
| |
| sprs.mmcra = mfspr(SPRN_MMCRA); |
| sprs.mmcr0 = mfspr(SPRN_MMCR0); |
| sprs.mmcr1 = mfspr(SPRN_MMCR1); |
| sprs.mmcr2 = mfspr(SPRN_MMCR2); |
| |
| sprs.ptcr = mfspr(SPRN_PTCR); |
| sprs.rpr = mfspr(SPRN_RPR); |
| sprs.tscr = mfspr(SPRN_TSCR); |
| if (!firmware_has_feature(FW_FEATURE_ULTRAVISOR)) |
| sprs.ldbar = mfspr(SPRN_LDBAR); |
| |
| sprs_saved = true; |
| |
| atomic_start_thread_idle(); |
| } |
| |
| sprs.amr = mfspr(SPRN_AMR); |
| sprs.iamr = mfspr(SPRN_IAMR); |
| sprs.amor = mfspr(SPRN_AMOR); |
| sprs.uamor = mfspr(SPRN_UAMOR); |
| |
| srr1 = isa300_idle_stop_mayloss(psscr); /* go idle */ |
| |
| #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE |
| local_paca->requested_psscr = 0; |
| #endif |
| |
| psscr = mfspr(SPRN_PSSCR); |
| |
| WARN_ON_ONCE(!srr1); |
| WARN_ON_ONCE(mfmsr() & (MSR_IR|MSR_DR)); |
| |
| if ((srr1 & SRR1_WAKESTATE) != SRR1_WS_NOLOSS) { |
| /* |
| * We don't need an isync after the mtsprs here because the |
| * upcoming mtmsrd is execution synchronizing. |
| */ |
| mtspr(SPRN_AMR, sprs.amr); |
| mtspr(SPRN_IAMR, sprs.iamr); |
| mtspr(SPRN_AMOR, sprs.amor); |
| mtspr(SPRN_UAMOR, sprs.uamor); |
| |
| /* |
| * Workaround for POWER9 DD2.0, if we lost resources, the ERAT |
| * might have been corrupted and needs flushing. We also need |
| * to reload MMCR0 (see mmcr0 comment above). |
| */ |
| if (!cpu_has_feature(CPU_FTR_POWER9_DD2_1)) { |
| asm volatile(PPC_ISA_3_0_INVALIDATE_ERAT); |
| mtspr(SPRN_MMCR0, mmcr0); |
| } |
| |
| /* |
| * DD2.2 and earlier need to set then clear bit 60 in MMCRA |
| * to ensure the PMU starts running. |
| */ |
| mmcra = mfspr(SPRN_MMCRA); |
| mmcra |= PPC_BIT(60); |
| mtspr(SPRN_MMCRA, mmcra); |
| mmcra &= ~PPC_BIT(60); |
| mtspr(SPRN_MMCRA, mmcra); |
| } |
| |
| if (unlikely((srr1 & SRR1_WAKEMASK_P8) == SRR1_WAKEHMI)) |
| hmi_exception_realmode(NULL); |
| |
| /* |
| * On POWER9, SRR1 bits do not match exactly as expected. |
| * SRR1_WS_GPRLOSS (10b) can also result in SPR loss, so |
| * just always test PSSCR for SPR/TB state loss. |
| */ |
| pls = (psscr & PSSCR_PLS) >> PSSCR_PLS_SHIFT; |
| if (likely(pls < deep_spr_loss_state)) { |
| if (sprs_saved) |
| atomic_stop_thread_idle(); |
| goto out; |
| } |
| |
| /* HV state loss */ |
| BUG_ON(!sprs_saved); |
| |
| atomic_lock_thread_idle(); |
| |
| if ((*state & core_thread_mask) != 0) |
| goto core_woken; |
| |
| /* Per-core SPRs */ |
| mtspr(SPRN_PTCR, sprs.ptcr); |
| mtspr(SPRN_RPR, sprs.rpr); |
| mtspr(SPRN_TSCR, sprs.tscr); |
| |
| if (pls >= pnv_first_tb_loss_level) { |
| /* TB loss */ |
| if (opal_resync_timebase() != OPAL_SUCCESS) |
| BUG(); |
| } |
| |
| /* |
| * isync after restoring shared SPRs and before unlocking. Unlock |
| * only contains hwsync which does not necessarily do the right |
| * thing for SPRs. |
| */ |
| isync(); |
| |
| core_woken: |
| atomic_unlock_and_stop_thread_idle(); |
| |
| /* Per-thread SPRs */ |
| mtspr(SPRN_LPCR, sprs.lpcr); |
| mtspr(SPRN_HFSCR, sprs.hfscr); |
| mtspr(SPRN_FSCR, sprs.fscr); |
| mtspr(SPRN_PID, sprs.pid); |
| mtspr(SPRN_PURR, sprs.purr); |
| mtspr(SPRN_SPURR, sprs.spurr); |
| mtspr(SPRN_DSCR, sprs.dscr); |
| mtspr(SPRN_CIABR, sprs.ciabr); |
| |
| mtspr(SPRN_MMCRA, sprs.mmcra); |
| mtspr(SPRN_MMCR0, sprs.mmcr0); |
| mtspr(SPRN_MMCR1, sprs.mmcr1); |
| mtspr(SPRN_MMCR2, sprs.mmcr2); |
| if (!firmware_has_feature(FW_FEATURE_ULTRAVISOR)) |
| mtspr(SPRN_LDBAR, sprs.ldbar); |
| |
| mtspr(SPRN_SPRG3, local_paca->sprg_vdso); |
| |
| if (!radix_enabled()) |
| __slb_restore_bolted_realmode(); |
| |
| out: |
| mtmsr(MSR_KERNEL); |
| |
| return srr1; |
| } |
| |
| #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE |
| /* |
| * This is used in working around bugs in thread reconfiguration |
| * on POWER9 (at least up to Nimbus DD2.2) relating to transactional |
| * memory and the way that XER[SO] is checkpointed. |
| * This function forces the core into SMT4 in order by asking |
| * all other threads not to stop, and sending a message to any |
| * that are in a stop state. |
| * Must be called with preemption disabled. |
| */ |
| void pnv_power9_force_smt4_catch(void) |
| { |
| int cpu, cpu0, thr; |
| int awake_threads = 1; /* this thread is awake */ |
| int poke_threads = 0; |
| int need_awake = threads_per_core; |
| |
| cpu = smp_processor_id(); |
| cpu0 = cpu & ~(threads_per_core - 1); |
| for (thr = 0; thr < threads_per_core; ++thr) { |
| if (cpu != cpu0 + thr) |
| atomic_inc(&paca_ptrs[cpu0+thr]->dont_stop); |
| } |
| /* order setting dont_stop vs testing requested_psscr */ |
| smp_mb(); |
| for (thr = 0; thr < threads_per_core; ++thr) { |
| if (!paca_ptrs[cpu0+thr]->requested_psscr) |
| ++awake_threads; |
| else |
| poke_threads |= (1 << thr); |
| } |
| |
| /* If at least 3 threads are awake, the core is in SMT4 already */ |
| if (awake_threads < need_awake) { |
| /* We have to wake some threads; we'll use msgsnd */ |
| for (thr = 0; thr < threads_per_core; ++thr) { |
| if (poke_threads & (1 << thr)) { |
| ppc_msgsnd_sync(); |
| ppc_msgsnd(PPC_DBELL_MSGTYPE, 0, |
| paca_ptrs[cpu0+thr]->hw_cpu_id); |
| } |
| } |
| /* now spin until at least 3 threads are awake */ |
| do { |
| for (thr = 0; thr < threads_per_core; ++thr) { |
| if ((poke_threads & (1 << thr)) && |
| !paca_ptrs[cpu0+thr]->requested_psscr) { |
| ++awake_threads; |
| poke_threads &= ~(1 << thr); |
| } |
| } |
| } while (awake_threads < need_awake); |
| } |
| } |
| EXPORT_SYMBOL_GPL(pnv_power9_force_smt4_catch); |
| |
| void pnv_power9_force_smt4_release(void) |
| { |
| int cpu, cpu0, thr; |
| |
| cpu = smp_processor_id(); |
| cpu0 = cpu & ~(threads_per_core - 1); |
| |
| /* clear all the dont_stop flags */ |
| for (thr = 0; thr < threads_per_core; ++thr) { |
| if (cpu != cpu0 + thr) |
| atomic_dec(&paca_ptrs[cpu0+thr]->dont_stop); |
| } |
| } |
| EXPORT_SYMBOL_GPL(pnv_power9_force_smt4_release); |
| #endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */ |
| |
| struct p10_sprs { |
| /* |
| * SPRs that get lost in shallow states: |
| * |
| * P10 loses CR, LR, CTR, FPSCR, VSCR, XER, TAR, SPRG2, and HSPRG1 |
| * isa300 idle routines restore CR, LR. |
| * CTR is volatile |
| * idle thread doesn't use FP or VEC |
| * kernel doesn't use TAR |
| * HSPRG1 is only live in HV interrupt entry |
| * SPRG2 is only live in KVM guests, KVM handles it. |
| */ |
| }; |
| |
| static unsigned long power10_idle_stop(unsigned long psscr) |
| { |
| int cpu = raw_smp_processor_id(); |
| int first = cpu_first_thread_sibling(cpu); |
| unsigned long *state = &paca_ptrs[first]->idle_state; |
| unsigned long core_thread_mask = (1UL << threads_per_core) - 1; |
| unsigned long srr1; |
| unsigned long pls; |
| // struct p10_sprs sprs = {}; /* avoid false used-uninitialised */ |
| bool sprs_saved = false; |
| |
| if (!(psscr & (PSSCR_EC|PSSCR_ESL))) { |
| /* EC=ESL=0 case */ |
| |
| /* |
| * Wake synchronously. SRESET via xscom may still cause |
| * a 0x100 powersave wakeup with SRR1 reason! |
| */ |
| srr1 = isa300_idle_stop_noloss(psscr); /* go idle */ |
| if (likely(!srr1)) |
| return 0; |
| |
| /* |
| * Registers not saved, can't recover! |
| * This would be a hardware bug |
| */ |
| BUG_ON((srr1 & SRR1_WAKESTATE) != SRR1_WS_NOLOSS); |
| |
| goto out; |
| } |
| |
| /* EC=ESL=1 case */ |
| if ((psscr & PSSCR_RL_MASK) >= deep_spr_loss_state) { |
| /* XXX: save SPRs for deep state loss here. */ |
| |
| sprs_saved = true; |
| |
| atomic_start_thread_idle(); |
| } |
| |
| srr1 = isa300_idle_stop_mayloss(psscr); /* go idle */ |
| |
| psscr = mfspr(SPRN_PSSCR); |
| |
| WARN_ON_ONCE(!srr1); |
| WARN_ON_ONCE(mfmsr() & (MSR_IR|MSR_DR)); |
| |
| if (unlikely((srr1 & SRR1_WAKEMASK_P8) == SRR1_WAKEHMI)) |
| hmi_exception_realmode(NULL); |
| |
| /* |
| * On POWER10, SRR1 bits do not match exactly as expected. |
| * SRR1_WS_GPRLOSS (10b) can also result in SPR loss, so |
| * just always test PSSCR for SPR/TB state loss. |
| */ |
| pls = (psscr & PSSCR_PLS) >> PSSCR_PLS_SHIFT; |
| if (likely(pls < deep_spr_loss_state)) { |
| if (sprs_saved) |
| atomic_stop_thread_idle(); |
| goto out; |
| } |
| |
| /* HV state loss */ |
| BUG_ON(!sprs_saved); |
| |
| atomic_lock_thread_idle(); |
| |
| if ((*state & core_thread_mask) != 0) |
| goto core_woken; |
| |
| /* XXX: restore per-core SPRs here */ |
| |
| if (pls >= pnv_first_tb_loss_level) { |
| /* TB loss */ |
| if (opal_resync_timebase() != OPAL_SUCCESS) |
| BUG(); |
| } |
| |
| /* |
| * isync after restoring shared SPRs and before unlocking. Unlock |
| * only contains hwsync which does not necessarily do the right |
| * thing for SPRs. |
| */ |
| isync(); |
| |
| core_woken: |
| atomic_unlock_and_stop_thread_idle(); |
| |
| /* XXX: restore per-thread SPRs here */ |
| |
| if (!radix_enabled()) |
| __slb_restore_bolted_realmode(); |
| |
| out: |
| mtmsr(MSR_KERNEL); |
| |
| return srr1; |
| } |
| |
| #ifdef CONFIG_HOTPLUG_CPU |
| static unsigned long arch300_offline_stop(unsigned long psscr) |
| { |
| unsigned long srr1; |
| |
| if (cpu_has_feature(CPU_FTR_ARCH_31)) |
| srr1 = power10_idle_stop(psscr); |
| else |
| srr1 = power9_idle_stop(psscr); |
| |
| return srr1; |
| } |
| #endif |
| |
| void arch300_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; |
| |
| psscr = mfspr(SPRN_PSSCR); |
| psscr = (psscr & ~stop_psscr_mask) | stop_psscr_val; |
| |
| __ppc64_runlatch_off(); |
| if (cpu_has_feature(CPU_FTR_ARCH_31)) |
| srr1 = power10_idle_stop(psscr); |
| else |
| srr1 = power9_idle_stop(psscr); |
| __ppc64_runlatch_on(); |
| |
| fini_irq_for_idle_irqsoff(); |
| |
| irq_set_pending_from_srr1(srr1); |
| } |
| |
| /* |
| * Used for ppc_md.power_save which needs a function with no parameters |
| */ |
| static void arch300_idle(void) |
| { |
| arch300_idle_type(pnv_default_stop_val, pnv_default_stop_mask); |
| } |
| |
| #ifdef CONFIG_HOTPLUG_CPU |
| |
| void pnv_program_cpu_hotplug_lpcr(unsigned int cpu, u64 lpcr_val) |
| { |
| u64 pir = get_hard_smp_processor_id(cpu); |
| |
| mtspr(SPRN_LPCR, lpcr_val); |
| |
| /* |
| * Program the LPCR via stop-api only if the deepest stop state |
| * can lose hypervisor context. |
| */ |
| if (supported_cpuidle_states & OPAL_PM_LOSE_FULL_CONTEXT) |
| opal_slw_set_reg(pir, SPRN_LPCR, lpcr_val); |
| } |
| |
| /* |
| * pnv_cpu_offline: A function that puts the CPU into the deepest |
| * available platform idle state on a CPU-Offline. |
| * interrupts hard disabled and no lazy irq pending. |
| */ |
| unsigned long pnv_cpu_offline(unsigned int cpu) |
| { |
| unsigned long srr1; |
| |
| __ppc64_runlatch_off(); |
| |
| if (cpu_has_feature(CPU_FTR_ARCH_300) && deepest_stop_found) { |
| unsigned long psscr; |
| |
| psscr = mfspr(SPRN_PSSCR); |
| psscr = (psscr & ~pnv_deepest_stop_psscr_mask) | |
| pnv_deepest_stop_psscr_val; |
| srr1 = arch300_offline_stop(psscr); |
| } else if (cpu_has_feature(CPU_FTR_ARCH_206) && power7_offline_type) { |
| srr1 = power7_offline(); |
| } else { |
| /* This is the fallback method. We emulate snooze */ |
| while (!generic_check_cpu_restart(cpu)) { |
| HMT_low(); |
| HMT_very_low(); |
| } |
| srr1 = 0; |
| HMT_medium(); |
| } |
| |
| __ppc64_runlatch_on(); |
| |
| return srr1; |
| } |
| #endif |
| |
| /* |
| * Power ISA 3.0 idle initialization. |
| * |
| * POWER ISA 3.0 defines a new SPR Processor stop Status and Control |
| * Register (PSSCR) to control idle behavior. |
| * |
| * PSSCR layout: |
| * ---------------------------------------------------------- |
| * | PLS | /// | SD | ESL | EC | PSLL | /// | TR | MTL | RL | |
| * ---------------------------------------------------------- |
| * 0 4 41 42 43 44 48 54 56 60 |
| * |
| * PSSCR key fields: |
| * Bits 0:3 - Power-Saving Level Status (PLS). This field indicates the |
| * lowest power-saving state the thread entered since stop instruction was |
| * last executed. |
| * |
| * Bit 41 - Status Disable(SD) |
| * 0 - Shows PLS entries |
| * 1 - PLS entries are all 0 |
| * |
| * Bit 42 - Enable State Loss |
| * 0 - No state is lost irrespective of other fields |
| * 1 - Allows state loss |
| * |
| * Bit 43 - Exit Criterion |
| * 0 - Exit from power-save mode on any interrupt |
| * 1 - Exit from power-save mode controlled by LPCR's PECE bits |
| * |
| * Bits 44:47 - Power-Saving Level Limit |
| * This limits the power-saving level that can be entered into. |
| * |
| * Bits 60:63 - Requested Level |
| * Used to specify which power-saving level must be entered on executing |
| * stop instruction |
| */ |
| |
| int validate_psscr_val_mask(u64 *psscr_val, u64 *psscr_mask, u32 flags) |
| { |
| int err = 0; |
| |
| /* |
| * psscr_mask == 0xf indicates an older firmware. |
| * Set remaining fields of psscr to the default values. |
| * See NOTE above definition of PSSCR_HV_DEFAULT_VAL |
| */ |
| if (*psscr_mask == 0xf) { |
| *psscr_val = *psscr_val | PSSCR_HV_DEFAULT_VAL; |
| *psscr_mask = PSSCR_HV_DEFAULT_MASK; |
| return err; |
| } |
| |
| /* |
| * New firmware is expected to set the psscr_val bits correctly. |
| * Validate that the following invariants are correctly maintained by |
| * the new firmware. |
| * - ESL bit value matches the EC bit value. |
| * - ESL bit is set for all the deep stop states. |
| */ |
| if (GET_PSSCR_ESL(*psscr_val) != GET_PSSCR_EC(*psscr_val)) { |
| err = ERR_EC_ESL_MISMATCH; |
| } else if ((flags & OPAL_PM_LOSE_FULL_CONTEXT) && |
| GET_PSSCR_ESL(*psscr_val) == 0) { |
| err = ERR_DEEP_STATE_ESL_MISMATCH; |
| } |
| |
| return err; |
| } |
| |
| /* |
| * pnv_arch300_idle_init: Initializes the default idle state, first |
| * deep idle state and deepest idle state on |
| * ISA 3.0 CPUs. |
| * |
| * @np: /ibm,opal/power-mgt device node |
| * @flags: cpu-idle-state-flags array |
| * @dt_idle_states: Number of idle state entries |
| * Returns 0 on success |
| */ |
| static void __init pnv_arch300_idle_init(void) |
| { |
| u64 max_residency_ns = 0; |
| int i; |
| |
| /* stop is not really architected, we only have p9,p10 drivers */ |
| if (!pvr_version_is(PVR_POWER10) && !pvr_version_is(PVR_POWER9)) |
| return; |
| |
| /* |
| * pnv_deepest_stop_{val,mask} should be set to values corresponding to |
| * the deepest stop state. |
| * |
| * pnv_default_stop_{val,mask} should be set to values corresponding to |
| * the deepest loss-less (OPAL_PM_STOP_INST_FAST) stop state. |
| */ |
| pnv_first_tb_loss_level = MAX_STOP_STATE + 1; |
| deep_spr_loss_state = MAX_STOP_STATE + 1; |
| for (i = 0; i < nr_pnv_idle_states; i++) { |
| int err; |
| struct pnv_idle_states_t *state = &pnv_idle_states[i]; |
| u64 psscr_rl = state->psscr_val & PSSCR_RL_MASK; |
| |
| /* No deep loss driver implemented for POWER10 yet */ |
| if (pvr_version_is(PVR_POWER10) && |
| state->flags & (OPAL_PM_TIMEBASE_STOP|OPAL_PM_LOSE_FULL_CONTEXT)) |
| continue; |
| |
| if ((state->flags & OPAL_PM_TIMEBASE_STOP) && |
| (pnv_first_tb_loss_level > psscr_rl)) |
| pnv_first_tb_loss_level = psscr_rl; |
| |
| if ((state->flags & OPAL_PM_LOSE_FULL_CONTEXT) && |
| (deep_spr_loss_state > psscr_rl)) |
| deep_spr_loss_state = psscr_rl; |
| |
| /* |
| * The idle code does not deal with TB loss occurring |
| * in a shallower state than SPR loss, so force it to |
| * behave like SPRs are lost if TB is lost. POWER9 would |
| * never encouter this, but a POWER8 core would if it |
| * implemented the stop instruction. So this is for forward |
| * compatibility. |
| */ |
| if ((state->flags & OPAL_PM_TIMEBASE_STOP) && |
| (deep_spr_loss_state > psscr_rl)) |
| deep_spr_loss_state = psscr_rl; |
| |
| err = validate_psscr_val_mask(&state->psscr_val, |
| &state->psscr_mask, |
| state->flags); |
| if (err) { |
| report_invalid_psscr_val(state->psscr_val, err); |
| continue; |
| } |
| |
| state->valid = true; |
| |
| if (max_residency_ns < state->residency_ns) { |
| max_residency_ns = state->residency_ns; |
| pnv_deepest_stop_psscr_val = state->psscr_val; |
| pnv_deepest_stop_psscr_mask = state->psscr_mask; |
| pnv_deepest_stop_flag = state->flags; |
| deepest_stop_found = true; |
| } |
| |
| if (!default_stop_found && |
| (state->flags & OPAL_PM_STOP_INST_FAST)) { |
| pnv_default_stop_val = state->psscr_val; |
| pnv_default_stop_mask = state->psscr_mask; |
| default_stop_found = true; |
| WARN_ON(state->flags & OPAL_PM_LOSE_FULL_CONTEXT); |
| } |
| } |
| |
| if (unlikely(!default_stop_found)) { |
| pr_warn("cpuidle-powernv: No suitable default stop state found. Disabling platform idle.\n"); |
| } else { |
| ppc_md.power_save = arch300_idle; |
| pr_info("cpuidle-powernv: Default stop: psscr = 0x%016llx,mask=0x%016llx\n", |
| pnv_default_stop_val, pnv_default_stop_mask); |
| } |
| |
| if (unlikely(!deepest_stop_found)) { |
| pr_warn("cpuidle-powernv: No suitable stop state for CPU-Hotplug. Offlined CPUs will busy wait"); |
| } else { |
| pr_info("cpuidle-powernv: Deepest stop: psscr = 0x%016llx,mask=0x%016llx\n", |
| pnv_deepest_stop_psscr_val, |
| pnv_deepest_stop_psscr_mask); |
| } |
| |
| pr_info("cpuidle-powernv: First stop level that may lose SPRs = 0x%llx\n", |
| deep_spr_loss_state); |
| |
| pr_info("cpuidle-powernv: First stop level that may lose timebase = 0x%llx\n", |
| pnv_first_tb_loss_level); |
| } |
| |
| static void __init pnv_disable_deep_states(void) |
| { |
| /* |
| * The stop-api is unable to restore hypervisor |
| * resources on wakeup from platform idle states which |
| * lose full context. So disable such states. |
| */ |
| supported_cpuidle_states &= ~OPAL_PM_LOSE_FULL_CONTEXT; |
| pr_warn("cpuidle-powernv: Disabling idle states that lose full context\n"); |
| pr_warn("cpuidle-powernv: Idle power-savings, CPU-Hotplug affected\n"); |
| |
| if (cpu_has_feature(CPU_FTR_ARCH_300) && |
| (pnv_deepest_stop_flag & OPAL_PM_LOSE_FULL_CONTEXT)) { |
| /* |
| * Use the default stop state for CPU-Hotplug |
| * if available. |
| */ |
| if (default_stop_found) { |
| pnv_deepest_stop_psscr_val = pnv_default_stop_val; |
| pnv_deepest_stop_psscr_mask = pnv_default_stop_mask; |
| pr_warn("cpuidle-powernv: Offlined CPUs will stop with psscr = 0x%016llx\n", |
| pnv_deepest_stop_psscr_val); |
| } else { /* Fallback to snooze loop for CPU-Hotplug */ |
| deepest_stop_found = false; |
| pr_warn("cpuidle-powernv: Offlined CPUs will busy wait\n"); |
| } |
| } |
| } |
| |
| /* |
| * Probe device tree for supported idle states |
| */ |
| static void __init pnv_probe_idle_states(void) |
| { |
| int i; |
| |
| if (nr_pnv_idle_states < 0) { |
| pr_warn("cpuidle-powernv: no idle states found in the DT\n"); |
| return; |
| } |
| |
| if (cpu_has_feature(CPU_FTR_ARCH_300)) |
| pnv_arch300_idle_init(); |
| |
| for (i = 0; i < nr_pnv_idle_states; i++) |
| supported_cpuidle_states |= pnv_idle_states[i].flags; |
| } |
| |
| /* |
| * This function parses device-tree and populates all the information |
| * into pnv_idle_states structure. It also sets up nr_pnv_idle_states |
| * which is the number of cpuidle states discovered through device-tree. |
| */ |
| |
| static int pnv_parse_cpuidle_dt(void) |
| { |
| struct device_node *np; |
| int nr_idle_states, i; |
| int rc = 0; |
| u32 *temp_u32; |
| u64 *temp_u64; |
| const char **temp_string; |
| |
| np = of_find_node_by_path("/ibm,opal/power-mgt"); |
| if (!np) { |
| pr_warn("opal: PowerMgmt Node not found\n"); |
| return -ENODEV; |
| } |
| nr_idle_states = of_property_count_u32_elems(np, |
| "ibm,cpu-idle-state-flags"); |
| |
| pnv_idle_states = kcalloc(nr_idle_states, sizeof(*pnv_idle_states), |
| GFP_KERNEL); |
| temp_u32 = kcalloc(nr_idle_states, sizeof(u32), GFP_KERNEL); |
| temp_u64 = kcalloc(nr_idle_states, sizeof(u64), GFP_KERNEL); |
| temp_string = kcalloc(nr_idle_states, sizeof(char *), GFP_KERNEL); |
| |
| if (!(pnv_idle_states && temp_u32 && temp_u64 && temp_string)) { |
| pr_err("Could not allocate memory for dt parsing\n"); |
| rc = -ENOMEM; |
| goto out; |
| } |
| |
| /* Read flags */ |
| if (of_property_read_u32_array(np, "ibm,cpu-idle-state-flags", |
| temp_u32, nr_idle_states)) { |
| pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-flags in DT\n"); |
| rc = -EINVAL; |
| goto out; |
| } |
| for (i = 0; i < nr_idle_states; i++) |
| pnv_idle_states[i].flags = temp_u32[i]; |
| |
| /* Read latencies */ |
| if (of_property_read_u32_array(np, "ibm,cpu-idle-state-latencies-ns", |
| temp_u32, nr_idle_states)) { |
| pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-latencies-ns in DT\n"); |
| rc = -EINVAL; |
| goto out; |
| } |
| for (i = 0; i < nr_idle_states; i++) |
| pnv_idle_states[i].latency_ns = temp_u32[i]; |
| |
| /* Read residencies */ |
| if (of_property_read_u32_array(np, "ibm,cpu-idle-state-residency-ns", |
| temp_u32, nr_idle_states)) { |
| pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-residency-ns in DT\n"); |
| rc = -EINVAL; |
| goto out; |
| } |
| for (i = 0; i < nr_idle_states; i++) |
| pnv_idle_states[i].residency_ns = temp_u32[i]; |
| |
| /* For power9 and later */ |
| if (cpu_has_feature(CPU_FTR_ARCH_300)) { |
| /* Read pm_crtl_val */ |
| if (of_property_read_u64_array(np, "ibm,cpu-idle-state-psscr", |
| temp_u64, nr_idle_states)) { |
| pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-psscr in DT\n"); |
| rc = -EINVAL; |
| goto out; |
| } |
| for (i = 0; i < nr_idle_states; i++) |
| pnv_idle_states[i].psscr_val = temp_u64[i]; |
| |
| /* Read pm_crtl_mask */ |
| if (of_property_read_u64_array(np, "ibm,cpu-idle-state-psscr-mask", |
| temp_u64, nr_idle_states)) { |
| pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-psscr-mask in DT\n"); |
| rc = -EINVAL; |
| goto out; |
| } |
| for (i = 0; i < nr_idle_states; i++) |
| pnv_idle_states[i].psscr_mask = temp_u64[i]; |
| } |
| |
| /* |
| * power8 specific properties ibm,cpu-idle-state-pmicr-mask and |
| * ibm,cpu-idle-state-pmicr-val were never used and there is no |
| * plan to use it in near future. Hence, not parsing these properties |
| */ |
| |
| if (of_property_read_string_array(np, "ibm,cpu-idle-state-names", |
| temp_string, nr_idle_states) < 0) { |
| pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-names in DT\n"); |
| rc = -EINVAL; |
| goto out; |
| } |
| for (i = 0; i < nr_idle_states; i++) |
| strlcpy(pnv_idle_states[i].name, temp_string[i], |
| PNV_IDLE_NAME_LEN); |
| nr_pnv_idle_states = nr_idle_states; |
| rc = 0; |
| out: |
| kfree(temp_u32); |
| kfree(temp_u64); |
| kfree(temp_string); |
| return rc; |
| } |
| |
| static int __init pnv_init_idle_states(void) |
| { |
| int cpu; |
| int rc = 0; |
| |
| /* Set up PACA fields */ |
| for_each_present_cpu(cpu) { |
| struct paca_struct *p = paca_ptrs[cpu]; |
| |
| p->idle_state = 0; |
| if (cpu == cpu_first_thread_sibling(cpu)) |
| p->idle_state = (1 << threads_per_core) - 1; |
| |
| if (!cpu_has_feature(CPU_FTR_ARCH_300)) { |
| /* P7/P8 nap */ |
| p->thread_idle_state = PNV_THREAD_RUNNING; |
| } else if (pvr_version_is(PVR_POWER9)) { |
| /* P9 stop workarounds */ |
| #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE |
| p->requested_psscr = 0; |
| atomic_set(&p->dont_stop, 0); |
| #endif |
| } |
| } |
| |
| /* In case we error out nr_pnv_idle_states will be zero */ |
| nr_pnv_idle_states = 0; |
| supported_cpuidle_states = 0; |
| |
| if (cpuidle_disable != IDLE_NO_OVERRIDE) |
| goto out; |
| rc = pnv_parse_cpuidle_dt(); |
| if (rc) |
| return rc; |
| pnv_probe_idle_states(); |
| |
| if (!cpu_has_feature(CPU_FTR_ARCH_300)) { |
| if (!(supported_cpuidle_states & OPAL_PM_SLEEP_ENABLED_ER1)) { |
| power7_fastsleep_workaround_entry = false; |
| power7_fastsleep_workaround_exit = false; |
| } else { |
| /* |
| * OPAL_PM_SLEEP_ENABLED_ER1 is set. It indicates that |
| * workaround is needed to use fastsleep. Provide sysfs |
| * control to choose how this workaround has to be |
| * applied. |
| */ |
| device_create_file(cpu_subsys.dev_root, |
| &dev_attr_fastsleep_workaround_applyonce); |
| } |
| |
| update_subcore_sibling_mask(); |
| |
| if (supported_cpuidle_states & OPAL_PM_NAP_ENABLED) { |
| ppc_md.power_save = power7_idle; |
| power7_offline_type = PNV_THREAD_NAP; |
| } |
| |
| if ((supported_cpuidle_states & OPAL_PM_WINKLE_ENABLED) && |
| (supported_cpuidle_states & OPAL_PM_LOSE_FULL_CONTEXT)) |
| power7_offline_type = PNV_THREAD_WINKLE; |
| else if ((supported_cpuidle_states & OPAL_PM_SLEEP_ENABLED) || |
| (supported_cpuidle_states & OPAL_PM_SLEEP_ENABLED_ER1)) |
| power7_offline_type = PNV_THREAD_SLEEP; |
| } |
| |
| if (supported_cpuidle_states & OPAL_PM_LOSE_FULL_CONTEXT) { |
| if (pnv_save_sprs_for_deep_states()) |
| pnv_disable_deep_states(); |
| } |
| |
| out: |
| return 0; |
| } |
| machine_subsys_initcall(powernv, pnv_init_idle_states); |