diff options
Diffstat (limited to 'arch/powerpc/platforms/powernv/idle.c')
| -rw-r--r-- | arch/powerpc/platforms/powernv/idle.c | 1535 |
1 files changed, 1535 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/powernv/idle.c b/arch/powerpc/platforms/powernv/idle.c new file mode 100644 index 000000000..1ed7c5286 --- /dev/null +++ b/arch/powerpc/platforms/powernv/idle.c @@ -0,0 +1,1535 @@ +// 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/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; + + get_online_cpus(); + primary_thread_mask = cpu_online_cores_map(); + on_each_cpu_mask(&primary_thread_mask, + pnv_fastsleep_workaround_apply, + &err, 1); + put_online_cpus(); + 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 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, bool mmu_on) +{ + 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 */ + + BUG_ON(!mmu_on); + + /* + * 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.wort = mfspr(SPRN_WORT); + + 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_WORT, sprs.wort); + + 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: + if (mmu_on) + 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, bool mmu_on) +{ + 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 */ + + BUG_ON(!mmu_on); + + /* + * 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: + if (mmu_on) + mtmsr(MSR_KERNEL); + + return srr1; +} + +#ifdef CONFIG_HOTPLUG_CPU +static unsigned long arch300_offline_stop(unsigned long psscr) +{ + unsigned long srr1; + +#ifndef CONFIG_KVM_BOOK3S_HV_POSSIBLE + __ppc64_runlatch_off(); + if (cpu_has_feature(CPU_FTR_ARCH_31)) + srr1 = power10_idle_stop(psscr, true); + else + srr1 = power9_idle_stop(psscr, true); + __ppc64_runlatch_on(); +#else + /* + * Tell KVM we're entering idle. + * This does not have to be done in real mode because the P9 MMU + * is independent per-thread. Some steppings share radix/hash mode + * between threads, but in that case KVM has a barrier sync in real + * mode before and after switching between radix and hash. + * + * kvm_start_guest must still be called in real mode though, hence + * the false argument. + */ + local_paca->kvm_hstate.hwthread_state = KVM_HWTHREAD_IN_IDLE; + + __ppc64_runlatch_off(); + if (cpu_has_feature(CPU_FTR_ARCH_31)) + srr1 = power10_idle_stop(psscr, false); + else + srr1 = power9_idle_stop(psscr, false); + __ppc64_runlatch_on(); + + 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); + mtmsr(MSR_KERNEL); +#endif + + 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, true); + else + srr1 = power9_idle_stop(psscr, true); + __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); |