/* * This file contains idle entry/exit functions for POWER7, * POWER8 and POWER9 CPUs. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #undef DEBUG /* * Use unused space in the interrupt stack to save and restore * registers for winkle support. */ #define _MMCR0 GPR0 #define _SDR1 GPR3 #define _PTCR GPR3 #define _RPR GPR4 #define _SPURR GPR5 #define _PURR GPR6 #define _TSCR GPR7 #define _DSCR GPR8 #define _AMOR GPR9 #define _WORT GPR10 #define _WORC GPR11 #define _LPCR GPR12 #define PSSCR_EC_ESL_MASK_SHIFTED (PSSCR_EC | PSSCR_ESL) >> 16 .text /* * Used by threads before entering deep idle states. Saves SPRs * in interrupt stack frame */ save_sprs_to_stack: /* * Note all register i.e per-core, per-subcore or per-thread is saved * here since any thread in the core might wake up first */ BEGIN_FTR_SECTION /* * Note - SDR1 is dropped in Power ISA v3. Hence not restoring * SDR1 here */ mfspr r3,SPRN_PTCR std r3,_PTCR(r1) mfspr r3,SPRN_LPCR std r3,_LPCR(r1) FTR_SECTION_ELSE mfspr r3,SPRN_SDR1 std r3,_SDR1(r1) ALT_FTR_SECTION_END_IFSET(CPU_FTR_ARCH_300) mfspr r3,SPRN_RPR std r3,_RPR(r1) mfspr r3,SPRN_SPURR std r3,_SPURR(r1) mfspr r3,SPRN_PURR std r3,_PURR(r1) mfspr r3,SPRN_TSCR std r3,_TSCR(r1) mfspr r3,SPRN_DSCR std r3,_DSCR(r1) mfspr r3,SPRN_AMOR std r3,_AMOR(r1) mfspr r3,SPRN_WORT std r3,_WORT(r1) mfspr r3,SPRN_WORC std r3,_WORC(r1) /* * On POWER9, there are idle states such as stop4, invoked via cpuidle, * that lose hypervisor resources. In such cases, we need to save * additional SPRs before entering those idle states so that they can * be restored to their older values on wakeup from the idle state. * * On POWER8, the only such deep idle state is winkle which is used * only in the context of CPU-Hotplug, where these additional SPRs are * reinitiazed to a sane value. Hence there is no need to save/restore * these SPRs. */ BEGIN_FTR_SECTION blr END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300) power9_save_additional_sprs: mfspr r3, SPRN_PID mfspr r4, SPRN_LDBAR std r3, STOP_PID(r13) std r4, STOP_LDBAR(r13) mfspr r3, SPRN_FSCR mfspr r4, SPRN_HFSCR std r3, STOP_FSCR(r13) std r4, STOP_HFSCR(r13) mfspr r3, SPRN_MMCRA mfspr r4, SPRN_MMCR0 std r3, STOP_MMCRA(r13) std r4, _MMCR0(r1) mfspr r3, SPRN_MMCR1 mfspr r4, SPRN_MMCR2 std r3, STOP_MMCR1(r13) std r4, STOP_MMCR2(r13) blr power9_restore_additional_sprs: ld r3,_LPCR(r1) ld r4, STOP_PID(r13) mtspr SPRN_LPCR,r3 mtspr SPRN_PID, r4 ld r3, STOP_LDBAR(r13) ld r4, STOP_FSCR(r13) mtspr SPRN_LDBAR, r3 mtspr SPRN_FSCR, r4 ld r3, STOP_HFSCR(r13) ld r4, STOP_MMCRA(r13) mtspr SPRN_HFSCR, r3 mtspr SPRN_MMCRA, r4 ld r3, _MMCR0(r1) ld r4, STOP_MMCR1(r13) mtspr SPRN_MMCR0, r3 mtspr SPRN_MMCR1, r4 ld r3, STOP_MMCR2(r13) mtspr SPRN_MMCR2, r3 blr /* * Used by threads when the lock bit of core_idle_state is set. * Threads will spin in HMT_LOW until the lock bit is cleared. * r14 - pointer to core_idle_state * r15 - used to load contents of core_idle_state * r9 - used as a temporary variable */ core_idle_lock_held: HMT_LOW 3: lwz r15,0(r14) andis. r15,r15,PNV_CORE_IDLE_LOCK_BIT@h bne 3b HMT_MEDIUM lwarx r15,0,r14 andis. r9,r15,PNV_CORE_IDLE_LOCK_BIT@h bne- core_idle_lock_held blr /* * Pass requested state in r3: * r3 - PNV_THREAD_NAP/SLEEP/WINKLE in POWER8 * - Requested PSSCR value in POWER9 * * Address of idle handler to branch to in realmode in r4 */ pnv_powersave_common: /* Use r3 to pass state nap/sleep/winkle */ /* NAP is a state loss, we create a regs frame on the * stack, fill it up with the state we care about and * stick a pointer to it in PACAR1. We really only * need to save PC, some CR bits and the NV GPRs, * but for now an interrupt frame will do. */ mtctr r4 mflr r0 std r0,16(r1) stdu r1,-INT_FRAME_SIZE(r1) std r0,_LINK(r1) std r0,_NIP(r1) /* We haven't lost state ... yet */ li r0,0 stb r0,PACA_NAPSTATELOST(r13) /* Continue saving state */ SAVE_GPR(2, r1) SAVE_NVGPRS(r1) mfcr r5 std r5,_CCR(r1) std r1,PACAR1(r13) BEGIN_FTR_SECTION /* * POWER9 does not require real mode to stop, and presently does not * set hwthread_state for KVM (threads don't share MMU context), so * we can remain in virtual mode for this. */ bctr END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300) /* * POWER8 * Go to real mode to do the nap, as required by the architecture. * Also, we need to be in real mode before setting hwthread_state, * because as soon as we do that, another thread can switch * the MMU context to the guest. */ LOAD_REG_IMMEDIATE(r7, MSR_IDLE) mtmsrd r7,0 bctr /* * This is the sequence required to execute idle instructions, as * specified in ISA v2.07 (and earlier). MSR[IR] and MSR[DR] must be 0. */ #define IDLE_STATE_ENTER_SEQ_NORET(IDLE_INST) \ /* Magic NAP/SLEEP/WINKLE mode enter sequence */ \ std r0,0(r1); \ ptesync; \ ld r0,0(r1); \ 236: cmpd cr0,r0,r0; \ bne 236b; \ IDLE_INST; .globl pnv_enter_arch207_idle_mode pnv_enter_arch207_idle_mode: #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE /* Tell KVM we're entering idle */ li r4,KVM_HWTHREAD_IN_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. */ /******************************************************/ stb r4,HSTATE_HWTHREAD_STATE(r13) #endif stb r3,PACA_THREAD_IDLE_STATE(r13) cmpwi cr3,r3,PNV_THREAD_SLEEP bge cr3,2f IDLE_STATE_ENTER_SEQ_NORET(PPC_NAP) /* No return */ 2: /* Sleep or winkle */ lbz r7,PACA_THREAD_MASK(r13) ld r14,PACA_CORE_IDLE_STATE_PTR(r13) li r5,0 beq cr3,3f lis r5,PNV_CORE_IDLE_WINKLE_COUNT@h 3: lwarx_loop1: lwarx r15,0,r14 andis. r9,r15,PNV_CORE_IDLE_LOCK_BIT@h bnel- core_idle_lock_held add r15,r15,r5 /* Add if winkle */ andc r15,r15,r7 /* Clear thread bit */ andi. r9,r15,PNV_CORE_IDLE_THREAD_BITS /* * If cr0 = 0, then current thread is the last thread of the core entering * sleep. Last thread needs to execute the hardware bug workaround code if * required by the platform. * Make the workaround call unconditionally here. The below branch call is * patched out when the idle states are discovered if the platform does not * require it. */ .global pnv_fastsleep_workaround_at_entry pnv_fastsleep_workaround_at_entry: beq fastsleep_workaround_at_entry stwcx. r15,0,r14 bne- lwarx_loop1 isync common_enter: /* common code for all the threads entering sleep or winkle */ bgt cr3,enter_winkle IDLE_STATE_ENTER_SEQ_NORET(PPC_SLEEP) fastsleep_workaround_at_entry: oris r15,r15,PNV_CORE_IDLE_LOCK_BIT@h stwcx. r15,0,r14 bne- lwarx_loop1 isync /* Fast sleep workaround */ li r3,1 li r4,1 bl opal_config_cpu_idle_state /* Unlock */ xoris r15,r15,PNV_CORE_IDLE_LOCK_BIT@h lwsync stw r15,0(r14) b common_enter enter_winkle: bl save_sprs_to_stack IDLE_STATE_ENTER_SEQ_NORET(PPC_WINKLE) /* * r3 - PSSCR value corresponding to the requested stop state. */ power_enter_stop: /* * Check if we are executing the lite variant with ESL=EC=0 */ andis. r4,r3,PSSCR_EC_ESL_MASK_SHIFTED clrldi r3,r3,60 /* r3 = Bits[60:63] = Requested Level (RL) */ bne .Lhandle_esl_ec_set PPC_STOP li r3,0 /* Since we didn't lose state, return 0 */ std r3, PACA_REQ_PSSCR(r13) /* * pnv_wakeup_noloss() expects r12 to contain the SRR1 value so * it can determine if the wakeup reason is an HMI in * CHECK_HMI_INTERRUPT. * * However, when we wakeup with ESL=0, SRR1 will not contain the wakeup * reason, so there is no point setting r12 to SRR1. * * Further, we clear r12 here, so that we don't accidentally enter the * HMI in pnv_wakeup_noloss() if the value of r12[42:45] == WAKE_HMI. */ li r12, 0 b pnv_wakeup_noloss .Lhandle_esl_ec_set: BEGIN_FTR_SECTION /* * POWER9 DD2.0 or earlier can incorrectly set PMAO when waking up after * a state-loss idle. Saving and restoring MMCR0 over idle is a * workaround. */ mfspr r4,SPRN_MMCR0 std r4,_MMCR0(r1) END_FTR_SECTION_IFCLR(CPU_FTR_POWER9_DD2_1) /* * Check if the requested state is a deep idle state. */ LOAD_REG_ADDRBASE(r5,pnv_first_deep_stop_state) ld r4,ADDROFF(pnv_first_deep_stop_state)(r5) cmpd r3,r4 bge .Lhandle_deep_stop PPC_STOP /* Does not return (system reset interrupt) */ .Lhandle_deep_stop: /* * Entering deep idle state. * Clear thread bit in PACA_CORE_IDLE_STATE, save SPRs to * stack and enter stop */ lbz r7,PACA_THREAD_MASK(r13) ld r14,PACA_CORE_IDLE_STATE_PTR(r13) lwarx_loop_stop: lwarx r15,0,r14 andis. r9,r15,PNV_CORE_IDLE_LOCK_BIT@h bnel- core_idle_lock_held andc r15,r15,r7 /* Clear thread bit */ stwcx. r15,0,r14 bne- lwarx_loop_stop isync bl save_sprs_to_stack PPC_STOP /* Does not return (system reset interrupt) */ /* * 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_ADDR(r4, pnv_enter_arch207_idle_mode) b pnv_powersave_common #define CHECK_HMI_INTERRUPT \ BEGIN_FTR_SECTION_NESTED(66); \ rlwinm r0,r12,45-31,0xf; /* extract wake reason field (P8) */ \ FTR_SECTION_ELSE_NESTED(66); \ rlwinm r0,r12,45-31,0xe; /* P7 wake reason field is 3 bits */ \ ALT_FTR_SECTION_END_NESTED_IFSET(CPU_FTR_ARCH_207S, 66); \ cmpwi r0,0xa; /* Hypervisor maintenance ? */ \ bne+ 20f; \ /* Invoke opal call to handle hmi */ \ ld r2,PACATOC(r13); \ ld r1,PACAR1(r13); \ std r3,ORIG_GPR3(r1); /* Save original r3 */ \ li r3,0; /* NULL argument */ \ bl hmi_exception_realmode; \ nop; \ ld r3,ORIG_GPR3(r1); /* Restore original r3 */ \ 20: nop; /* * Entered with MSR[EE]=0 and no soft-masked interrupts pending. * r3 contains desired PSSCR register value. * * Offline (CPU unplug) case also must notify KVM that the CPU is * idle. */ _GLOBAL(power9_offline_stop) #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE /* * 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. */ li r4,KVM_HWTHREAD_IN_IDLE stb r4,HSTATE_HWTHREAD_STATE(r13) #endif /* fall through */ _GLOBAL(power9_idle_stop) std r3, PACA_REQ_PSSCR(r13) #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE BEGIN_FTR_SECTION sync lwz r5, PACA_DONT_STOP(r13) cmpwi r5, 0 bne 1f END_FTR_SECTION_IFSET(CPU_FTR_P9_TM_XER_SO_BUG) #endif mtspr SPRN_PSSCR,r3 LOAD_REG_ADDR(r4,power_enter_stop) b pnv_powersave_common /* No return */ #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE 1: /* * We get here when TM / thread reconfiguration bug workaround * code wants to get the CPU into SMT4 mode, and therefore * we are being asked not to stop. */ li r3, 0 std r3, PACA_REQ_PSSCR(r13) blr /* return 0 for wakeup cause / SRR1 value */ #endif /* * Called from machine check handler for powersave wakeups. * Low level machine check processing has already been done. Now just * go through the wake up path to get everything in order. * * r3 - The original SRR1 value. * Original SRR[01] have been clobbered. * MSR_RI is clear. */ .global pnv_powersave_wakeup_mce pnv_powersave_wakeup_mce: /* Set cr3 for pnv_powersave_wakeup */ rlwinm r11,r3,47-31,30,31 cmpwi cr3,r11,2 /* * Now put the original SRR1 with SRR1_WAKEMCE_RESVD as the wake * reason into r12, which allows reuse of the system reset wakeup * code without being mistaken for another type of wakeup. */ oris r12,r3,SRR1_WAKEMCE_RESVD@h b pnv_powersave_wakeup /* * Called from reset vector for powersave wakeups. * cr3 - set to gt if waking up with partial/complete hypervisor state loss * r12 - SRR1 */ .global pnv_powersave_wakeup pnv_powersave_wakeup: ld r2, PACATOC(r13) BEGIN_FTR_SECTION bl pnv_restore_hyp_resource_arch300 FTR_SECTION_ELSE bl pnv_restore_hyp_resource_arch207 ALT_FTR_SECTION_END_IFSET(CPU_FTR_ARCH_300) li r0,PNV_THREAD_RUNNING stb r0,PACA_THREAD_IDLE_STATE(r13) /* Clear thread state */ mr r3,r12 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE lbz r0,HSTATE_HWTHREAD_STATE(r13) cmpwi r0,KVM_HWTHREAD_IN_KERNEL beq 0f li r0,KVM_HWTHREAD_IN_KERNEL stb r0,HSTATE_HWTHREAD_STATE(r13) /* Order setting hwthread_state vs. testing hwthread_req */ sync 0: lbz r0,HSTATE_HWTHREAD_REQ(r13) cmpwi r0,0 beq 1f b kvm_start_guest 1: #endif /* Return SRR1 from power7_nap() */ blt cr3,pnv_wakeup_noloss b pnv_wakeup_loss /* * Check whether we have woken up with hypervisor state loss. * If yes, restore hypervisor state and return back to link. * * cr3 - set to gt if waking up with partial/complete hypervisor state loss */ pnv_restore_hyp_resource_arch300: /* * Workaround for POWER9, if we lost resources, the ERAT * might have been mixed up and needs flushing. We also need * to reload MMCR0 (see comment above). We also need to set * then clear bit 60 in MMCRA to ensure the PMU starts running. */ blt cr3,1f BEGIN_FTR_SECTION PPC_INVALIDATE_ERAT ld r1,PACAR1(r13) ld r4,_MMCR0(r1) mtspr SPRN_MMCR0,r4 END_FTR_SECTION_IFCLR(CPU_FTR_POWER9_DD2_1) mfspr r4,SPRN_MMCRA ori r4,r4,(1 << (63-60)) mtspr SPRN_MMCRA,r4 xori r4,r4,(1 << (63-60)) mtspr SPRN_MMCRA,r4 1: /* * POWER ISA 3. Use PSSCR to determine if we * are waking up from deep idle state */ LOAD_REG_ADDRBASE(r5,pnv_first_deep_stop_state) ld r4,ADDROFF(pnv_first_deep_stop_state)(r5) /* * 0-3 bits correspond to Power-Saving Level Status * which indicates the idle state we are waking up from */ mfspr r5, SPRN_PSSCR rldicl r5,r5,4,60 li r0, 0 /* clear requested_psscr to say we're awake */ std r0, PACA_REQ_PSSCR(r13) cmpd cr4,r5,r4 bge cr4,pnv_wakeup_tb_loss /* returns to caller */ blr /* Waking up without hypervisor state loss. */ /* Same calling convention as arch300 */ pnv_restore_hyp_resource_arch207: /* * POWER ISA 2.07 or less. * Check if we slept with sleep or winkle. */ lbz r4,PACA_THREAD_IDLE_STATE(r13) cmpwi cr2,r4,PNV_THREAD_NAP bgt cr2,pnv_wakeup_tb_loss /* Either sleep or Winkle */ /* * We fall through here if PACA_THREAD_IDLE_STATE shows we are waking * up from nap. At this stage CR3 shouldn't contains 'gt' since that * indicates we are waking with hypervisor state loss from nap. */ bgt cr3,. blr /* Waking up without hypervisor state loss */ /* * Called if waking up from idle state which can cause either partial or * complete hyp state loss. * In POWER8, called if waking up from fastsleep or winkle * In POWER9, called if waking up from stop state >= pnv_first_deep_stop_state * * r13 - PACA * cr3 - gt if waking up with partial/complete hypervisor state loss * * If ISA300: * cr4 - gt or eq if waking up from complete hypervisor state loss. * * If ISA207: * r4 - PACA_THREAD_IDLE_STATE */ pnv_wakeup_tb_loss: ld r1,PACAR1(r13) /* * Before entering any idle state, the NVGPRs are saved in the stack. * If there was a state loss, or PACA_NAPSTATELOST was set, then the * NVGPRs are restored. If we are here, it is likely that state is lost, * but not guaranteed -- neither ISA207 nor ISA300 tests to reach * here are the same as the test to restore NVGPRS: * PACA_THREAD_IDLE_STATE test for ISA207, PSSCR test for ISA300, * and SRR1 test for restoring NVGPRs. * * We are about to clobber NVGPRs now, so set NAPSTATELOST to * guarantee they will always be restored. This might be tightened * with careful reading of specs (particularly for ISA300) but this * is already a slow wakeup path and it's simpler to be safe. */ li r0,1 stb r0,PACA_NAPSTATELOST(r13) /* * * Save SRR1 and LR in NVGPRs as they might be clobbered in * opal_call() (called in CHECK_HMI_INTERRUPT). SRR1 is required * to determine the wakeup reason if we branch to kvm_start_guest. LR * is required to return back to reset vector after hypervisor state * restore is complete. */ mr r19,r12 mr r18,r4 mflr r17 BEGIN_FTR_SECTION CHECK_HMI_INTERRUPT END_FTR_SECTION_IFSET(CPU_FTR_HVMODE) ld r14,PACA_CORE_IDLE_STATE_PTR(r13) lbz r7,PACA_THREAD_MASK(r13) /* * Take the core lock to synchronize against other threads. * * Lock bit is set in one of the 2 cases- * a. In the sleep/winkle enter path, the last thread is executing * fastsleep workaround code. * b. In the wake up path, another thread is executing fastsleep * workaround undo code or resyncing timebase or restoring context * In either case loop until the lock bit is cleared. */ 1: lwarx r15,0,r14 andis. r9,r15,PNV_CORE_IDLE_LOCK_BIT@h bnel- core_idle_lock_held oris r15,r15,PNV_CORE_IDLE_LOCK_BIT@h stwcx. r15,0,r14 bne- 1b isync andi. r9,r15,PNV_CORE_IDLE_THREAD_BITS cmpwi cr2,r9,0 /* * At this stage * cr2 - eq if first thread to wakeup in core * cr3- gt if waking up with partial/complete hypervisor state loss * ISA300: * cr4 - gt or eq if waking up from complete hypervisor state loss. */ BEGIN_FTR_SECTION /* * Were we in winkle? * If yes, check if all threads were in winkle, decrement our * winkle count, set all thread winkle bits if all were in winkle. * Check if our thread has a winkle bit set, and set cr4 accordingly * (to match ISA300, above). Pseudo-code for core idle state * transitions for ISA207 is as follows (everything happens atomically * due to store conditional and/or lock bit): * * nap_idle() { } * nap_wake() { } * * sleep_idle() * { * core_idle_state &= ~thread_in_core * } * * sleep_wake() * { * bool first_in_core, first_in_subcore; * * first_in_core = (core_idle_state & IDLE_THREAD_BITS) == 0; * first_in_subcore = (core_idle_state & SUBCORE_SIBLING_MASK) == 0; * * core_idle_state |= thread_in_core; * } * * winkle_idle() * { * core_idle_state &= ~thread_in_core; * core_idle_state += 1 << WINKLE_COUNT_SHIFT; * } * * winkle_wake() * { * bool first_in_core, first_in_subcore, winkle_state_lost; * * first_in_core = (core_idle_state & IDLE_THREAD_BITS) == 0; * first_in_subcore = (core_idle_state & SUBCORE_SIBLING_MASK) == 0; * * core_idle_state |= thread_in_core; * * if ((core_idle_state & WINKLE_MASK) == (8 << WINKLE_COUNT_SIHFT)) * core_idle_state |= THREAD_WINKLE_BITS; * core_idle_state -= 1 << WINKLE_COUNT_SHIFT; * * winkle_state_lost = core_idle_state & * (thread_in_core << WINKLE_THREAD_SHIFT); * core_idle_state &= ~(thread_in_core << WINKLE_THREAD_SHIFT); * } * */ cmpwi r18,PNV_THREAD_WINKLE bne 2f andis. r9,r15,PNV_CORE_IDLE_WINKLE_COUNT_ALL_BIT@h subis r15,r15,PNV_CORE_IDLE_WINKLE_COUNT@h beq 2f ori r15,r15,PNV_CORE_IDLE_THREAD_WINKLE_BITS /* all were winkle */ 2: /* Shift thread bit to winkle mask, then test if this thread is set, * and remove it from the winkle bits */ slwi r8,r7,8 and r8,r8,r15 andc r15,r15,r8 cmpwi cr4,r8,1 /* cr4 will be gt if our bit is set, lt if not */ lbz r4,PACA_SUBCORE_SIBLING_MASK(r13) and r4,r4,r15 cmpwi r4,0 /* Check if first in subcore */ or r15,r15,r7 /* Set thread bit */ beq first_thread_in_subcore END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300) or r15,r15,r7 /* Set thread bit */ beq cr2,first_thread_in_core /* Not first thread in core or subcore to wake up */ b clear_lock first_thread_in_subcore: /* * If waking up from sleep, subcore state is not lost. Hence * skip subcore state restore */ blt cr4,subcore_state_restored /* Restore per-subcore state */ ld r4,_SDR1(r1) mtspr SPRN_SDR1,r4 ld r4,_RPR(r1) mtspr SPRN_RPR,r4 ld r4,_AMOR(r1) mtspr SPRN_AMOR,r4 subcore_state_restored: /* * Check if the thread is also the first thread in the core. If not, * skip to clear_lock. */ bne cr2,clear_lock first_thread_in_core: /* * First thread in the core waking up from any state which can cause * partial or complete hypervisor state loss. It needs to * call the fastsleep workaround code if the platform requires it. * Call it unconditionally here. The below branch instruction will * be patched out if the platform does not have fastsleep or does not * require the workaround. Patching will be performed during the * discovery of idle-states. */ .global pnv_fastsleep_workaround_at_exit pnv_fastsleep_workaround_at_exit: b fastsleep_workaround_at_exit timebase_resync: /* * Use cr3 which indicates that we are waking up with atleast partial * hypervisor state loss to determine if TIMEBASE RESYNC is needed. */ ble cr3,.Ltb_resynced /* Time base re-sync */ bl opal_resync_timebase; /* * If waking up from sleep (POWER8), per core state * is not lost, skip to clear_lock. */ .Ltb_resynced: blt cr4,clear_lock /* * First thread in the core to wake up and its waking up with * complete hypervisor state loss. Restore per core hypervisor * state. */ BEGIN_FTR_SECTION ld r4,_PTCR(r1) mtspr SPRN_PTCR,r4 ld r4,_RPR(r1) mtspr SPRN_RPR,r4 ld r4,_AMOR(r1) mtspr SPRN_AMOR,r4 END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300) ld r4,_TSCR(r1) mtspr SPRN_TSCR,r4 ld r4,_WORC(r1) mtspr SPRN_WORC,r4 clear_lock: xoris r15,r15,PNV_CORE_IDLE_LOCK_BIT@h lwsync stw r15,0(r14) common_exit: /* * Common to all threads. * * If waking up from sleep, hypervisor state is not lost. Hence * skip hypervisor state restore. */ blt cr4,hypervisor_state_restored /* Waking up from winkle */ BEGIN_MMU_FTR_SECTION b no_segments END_MMU_FTR_SECTION_IFSET(MMU_FTR_TYPE_RADIX) /* Restore SLB from PACA */ ld r8,PACA_SLBSHADOWPTR(r13) .rept SLB_NUM_BOLTED li r3, SLBSHADOW_SAVEAREA LDX_BE r5, r8, r3 addi r3, r3, 8 LDX_BE r6, r8, r3 andis. r7,r5,SLB_ESID_V@h beq 1f slbmte r6,r5 1: addi r8,r8,16 .endr no_segments: /* Restore per thread state */ ld r4,_SPURR(r1) mtspr SPRN_SPURR,r4 ld r4,_PURR(r1) mtspr SPRN_PURR,r4 ld r4,_DSCR(r1) mtspr SPRN_DSCR,r4 ld r4,_WORT(r1) mtspr SPRN_WORT,r4 /* Call cur_cpu_spec->cpu_restore() */ LOAD_REG_ADDR(r4, cur_cpu_spec) ld r4,0(r4) ld r12,CPU_SPEC_RESTORE(r4) #ifdef PPC64_ELF_ABI_v1 ld r12,0(r12) #endif mtctr r12 bctrl /* * On POWER9, we can come here on wakeup from a cpuidle stop state. * Hence restore the additional SPRs to the saved value. * * On POWER8, we come here only on winkle. Since winkle is used * only in the case of CPU-Hotplug, we don't need to restore * the additional SPRs. */ BEGIN_FTR_SECTION bl power9_restore_additional_sprs END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300) hypervisor_state_restored: mr r12,r19 mtlr r17 blr /* return to pnv_powersave_wakeup */ fastsleep_workaround_at_exit: li r3,1 li r4,0 bl opal_config_cpu_idle_state b timebase_resync /* * R3 here contains the value that will be returned to the caller * of power7_nap. * R12 contains SRR1 for CHECK_HMI_INTERRUPT. */ .global pnv_wakeup_loss pnv_wakeup_loss: ld r1,PACAR1(r13) BEGIN_FTR_SECTION CHECK_HMI_INTERRUPT END_FTR_SECTION_IFSET(CPU_FTR_HVMODE) REST_NVGPRS(r1) REST_GPR(2, r1) ld r4,PACAKMSR(r13) ld r5,_LINK(r1) ld r6,_CCR(r1) addi r1,r1,INT_FRAME_SIZE mtlr r5 mtcr r6 mtmsrd r4 blr /* * R3 here contains the value that will be returned to the caller * of power7_nap. * R12 contains SRR1 for CHECK_HMI_INTERRUPT. */ pnv_wakeup_noloss: lbz r0,PACA_NAPSTATELOST(r13) cmpwi r0,0 bne pnv_wakeup_loss ld r1,PACAR1(r13) BEGIN_FTR_SECTION CHECK_HMI_INTERRUPT END_FTR_SECTION_IFSET(CPU_FTR_HVMODE) ld r4,PACAKMSR(r13) ld r5,_NIP(r1) ld r6,_CCR(r1) addi r1,r1,INT_FRAME_SIZE mtlr r5 mtcr r6 mtmsrd r4 blr