Reimplement POWER9 idle code in C, in the powernv platform code.
Assembly stubs are used to save and restore the stack frame and
non-volatile GPRs before going to idle, but these are small and
mostly agnostic to microarchitecture implementation details.

POWER7/8 code is not converted (yet), but that's not a moving
target, and it doesn't make you want to claw your eyes out so
much with the POWER9 code untangled from it.

The optimisation where EC=ESL=0 idle modes did not have to save
GPRs or mtmsrd L=0 is restored, because it's simple to do.

Idle wakeup no longer uses the ->cpu_restore call to reinit SPRs,
but saves and restores them all explicitly.

Moving the HMI, SPR, OPAL, locking, etc. to C is the only real
way this stuff will cope with non-trivial new CPU implementation
details, firmware changes, etc., without becoming unmaintainable.
---
 arch/powerpc/include/asm/book3s/64/mmu-hash.h |   1 +
 arch/powerpc/include/asm/cpuidle.h            |  14 +-
 arch/powerpc/include/asm/paca.h               |  38 +-
 arch/powerpc/include/asm/processor.h          |   3 +-
 arch/powerpc/include/asm/reg.h                |   7 +-
 arch/powerpc/kernel/Makefile                  |   2 +-
 arch/powerpc/kernel/asm-offsets.c             |  11 +-
 arch/powerpc/kernel/exceptions-64s.S          |  10 +-
 arch/powerpc/kernel/idle_book3s.S             | 348 ++-------------
 arch/powerpc/kernel/idle_isa3.S               |  73 ++++
 arch/powerpc/kernel/setup-common.c            |   4 +-
 arch/powerpc/mm/slb.c                         |   7 +-
 arch/powerpc/platforms/powernv/idle.c         | 402 +++++++++++++++---
 arch/powerpc/xmon/xmon.c                      |  25 +-
 14 files changed, 496 insertions(+), 449 deletions(-)
 create mode 100644 arch/powerpc/kernel/idle_isa3.S

diff --git a/arch/powerpc/include/asm/book3s/64/mmu-hash.h 
b/arch/powerpc/include/asm/book3s/64/mmu-hash.h
index 50ed64fba4ae..c626319a962d 100644
--- a/arch/powerpc/include/asm/book3s/64/mmu-hash.h
+++ b/arch/powerpc/include/asm/book3s/64/mmu-hash.h
@@ -486,6 +486,7 @@ static inline void hpte_init_pseries(void) { }
 extern void hpte_init_native(void);
 
 extern void slb_initialize(void);
+extern void __slb_flush_and_rebolt(void);
 extern void slb_flush_and_rebolt(void);
 
 extern void slb_vmalloc_update(void);
diff --git a/arch/powerpc/include/asm/cpuidle.h 
b/arch/powerpc/include/asm/cpuidle.h
index e210a83eb196..b668f030d531 100644
--- a/arch/powerpc/include/asm/cpuidle.h
+++ b/arch/powerpc/include/asm/cpuidle.h
@@ -28,6 +28,7 @@
  * yet woken from the winkle state.
  */
 #define PNV_CORE_IDLE_LOCK_BIT                 0x10000000
+#define NR_PNV_CORE_IDLE_LOCK_BIT              28
 
 #define PNV_CORE_IDLE_WINKLE_COUNT             0x00010000
 #define PNV_CORE_IDLE_WINKLE_COUNT_ALL_BIT     0x00080000
@@ -68,22 +69,9 @@
 #define ERR_DEEP_STATE_ESL_MISMATCH    -2
 
 #ifndef __ASSEMBLY__
-/* Additional SPRs that need to be saved/restored during stop */
-struct stop_sprs {
-       u64 pid;
-       u64 ldbar;
-       u64 fscr;
-       u64 hfscr;
-       u64 mmcr1;
-       u64 mmcr2;
-       u64 mmcra;
-};
-
 extern u32 pnv_fastsleep_workaround_at_entry[];
 extern u32 pnv_fastsleep_workaround_at_exit[];
 
-extern u64 pnv_first_deep_stop_state;
-
 unsigned long pnv_cpu_offline(unsigned int cpu);
 int validate_psscr_val_mask(u64 *psscr_val, u64 *psscr_mask, u32 flags);
 static inline void report_invalid_psscr_val(u64 psscr_val, int err)
diff --git a/arch/powerpc/include/asm/paca.h b/arch/powerpc/include/asm/paca.h
index 4e9cede5a7e7..a7a4892d39c0 100644
--- a/arch/powerpc/include/asm/paca.h
+++ b/arch/powerpc/include/asm/paca.h
@@ -178,23 +178,29 @@ struct paca_struct {
 #endif
 
 #ifdef CONFIG_PPC_POWERNV
-       /* Per-core mask tracking idle threads and a lock bit-[L][TTTTTTTT] */
-       u32 *core_idle_state_ptr;
-       u8 thread_idle_state;           /* PNV_THREAD_RUNNING/NAP/SLEEP */
-       /* Mask to indicate thread id in core */
-       u8 thread_mask;
-       /* Mask to denote subcore sibling threads */
-       u8 subcore_sibling_mask;
-       /* Flag to request this thread not to stop */
-       atomic_t dont_stop;
-       /* The PSSCR value that the kernel requested before going to stop */
-       u64 requested_psscr;
+       union {
+               /* P7/P8 specific fields */
+               struct {
+                       /* Per-core mask tracking idle threads and a lock 
bit-[L][TTTTTTTT] */
+                       unsigned long *core_idle_state_ptr;
+                       u8 thread_idle_state;   /* PNV_THREAD_RUNNING/NAP/SLEEP 
*/
+                       /* Mask to indicate thread id in core */
+                       u8 thread_mask;
+                       /* Mask to denote subcore sibling threads */
+                       u8 subcore_sibling_mask;
+               };
 
-       /*
-        * Save area for additional SPRs that need to be
-        * saved/restored during cpuidle stop.
-        */
-       struct stop_sprs stop_sprs;
+               /* P9 specific fields */
+               struct {
+                       /* The PSSCR value that the kernel requested before 
going to stop */
+                       u64 requested_psscr;
+                       unsigned long idle_state;
+#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
+                       /* Flag to request this thread not to stop */
+                       atomic_t dont_stop;
+#endif
+               };
+       };
 #endif
 
 #ifdef CONFIG_PPC_BOOK3S_64
diff --git a/arch/powerpc/include/asm/processor.h 
b/arch/powerpc/include/asm/processor.h
index 5debe337ea9d..4774ec7603ee 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -513,7 +513,8 @@ enum idle_boot_override {IDLE_NO_OVERRIDE = 0, 
IDLE_POWERSAVE_OFF};
 extern int powersave_nap;      /* set if nap mode can be used in idle loop */
 extern unsigned long power7_idle_insn(unsigned long type); /* 
PNV_THREAD_NAP/etc*/
 extern void power7_idle_type(unsigned long type);
-extern unsigned long power9_idle_stop(unsigned long psscr_val);
+extern unsigned long isa3_idle_stop_noloss(unsigned long psscr_val);
+extern unsigned long isa3_idle_stop_mayloss(unsigned long psscr_val);
 extern unsigned long power9_offline_stop(unsigned long psscr_val);
 extern void power9_idle_type(unsigned long stop_psscr_val,
                              unsigned long stop_psscr_mask);
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index 562568414cf4..3c7d97b2abb0 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -750,10 +750,9 @@
 #define          SRR1_WAKERESET        0x00100000 /* System reset */
 #define   SRR1_WAKEHDBELL      0x000c0000 /* Hypervisor doorbell on P8 */
 #define          SRR1_WAKESTATE        0x00030000 /* Powersave exit mask 
[46:47] */
-#define          SRR1_WS_DEEPEST       0x00030000 /* Some resources not 
maintained,
-                                         * may not be recoverable */
-#define          SRR1_WS_DEEPER        0x00020000 /* Some resources not 
maintained */
-#define          SRR1_WS_DEEP          0x00010000 /* All resources maintained 
*/
+#define          SRR1_WS_HVLOSS        0x00030000 /* HV resources not 
maintained */
+#define          SRR1_WS_GPRLOSS       0x00020000 /* GPRs not maintained */
+#define          SRR1_WS_NOLOSS        0x00010000 /* All resources maintained 
*/
 #define   SRR1_PROGTM          0x00200000 /* TM Bad Thing */
 #define   SRR1_PROGFPE         0x00100000 /* Floating Point Enabled */
 #define   SRR1_PROGILL         0x00080000 /* Illegal instruction */
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index 2b4c40b255e4..6914fab16e2c 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -48,7 +48,7 @@ obj-$(CONFIG_PPC_BOOK3E_64)   += exceptions-64e.o 
idle_book3e.o
 obj-$(CONFIG_PPC64)            += vdso64/
 obj-$(CONFIG_ALTIVEC)          += vecemu.o
 obj-$(CONFIG_PPC_970_NAP)      += idle_power4.o
-obj-$(CONFIG_PPC_P7_NAP)       += idle_book3s.o
+obj-$(CONFIG_PPC_P7_NAP)       += idle_book3s.o idle_isa3.o
 procfs-y                       := proc_powerpc.o
 obj-$(CONFIG_PROC_FS)          += $(procfs-y)
 rtaspci-$(CONFIG_PPC64)-$(CONFIG_PCI)  := rtas_pci.o
diff --git a/arch/powerpc/kernel/asm-offsets.c 
b/arch/powerpc/kernel/asm-offsets.c
index 89cf15566c4e..b8162bb80ddb 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -762,20 +762,11 @@ int main(void)
 #endif
 
 #ifdef CONFIG_PPC_POWERNV
+       /* POWER7/8 specific idle fields (kernel/idle_book3s.S) */
        OFFSET(PACA_CORE_IDLE_STATE_PTR, paca_struct, core_idle_state_ptr);
        OFFSET(PACA_THREAD_IDLE_STATE, paca_struct, thread_idle_state);
        OFFSET(PACA_THREAD_MASK, paca_struct, thread_mask);
        OFFSET(PACA_SUBCORE_SIBLING_MASK, paca_struct, subcore_sibling_mask);
-       OFFSET(PACA_REQ_PSSCR, paca_struct, requested_psscr);
-       OFFSET(PACA_DONT_STOP, paca_struct, dont_stop);
-#define STOP_SPR(x, f) OFFSET(x, paca_struct, stop_sprs.f)
-       STOP_SPR(STOP_PID, pid);
-       STOP_SPR(STOP_LDBAR, ldbar);
-       STOP_SPR(STOP_FSCR, fscr);
-       STOP_SPR(STOP_HFSCR, hfscr);
-       STOP_SPR(STOP_MMCR1, mmcr1);
-       STOP_SPR(STOP_MMCR2, mmcr2);
-       STOP_SPR(STOP_MMCRA, mmcra);
 #endif
 
        DEFINE(PPC_DBELL_SERVER, PPC_DBELL_SERVER);
diff --git a/arch/powerpc/kernel/exceptions-64s.S 
b/arch/powerpc/kernel/exceptions-64s.S
index 76a14702cb9c..36b5f0e18c0c 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -135,8 +135,14 @@ TRAMP_KVM(PACA_EXNMI, 0x100)
 
 #ifdef CONFIG_PPC_P7_NAP
 EXC_COMMON_BEGIN(system_reset_idle_common)
+BEGIN_FTR_SECTION
+       mfspr   r3,SPRN_SRR1
+       bltlr   cr3     /* no state loss, return to idle caller */
+       b       isa3_idle_wake_gpr_loss
+FTR_SECTION_ELSE
        mfspr   r12,SPRN_SRR1
        b       pnv_powersave_wakeup
+ALT_FTR_SECTION_END_IFSET(CPU_FTR_ARCH_300)
 #endif
 
 /*
@@ -425,7 +431,9 @@ EXC_COMMON_BEGIN(machine_check_idle_common)
        li      r11,0
        mtmsrd  r11,1
 
-       b       pnv_powersave_wakeup_mce
+       /* XXX fixup
+       b       pnv_powersave_wakeup_mce */
+       b       .
 #endif
        /*
         * Handle machine check early in real mode. We come here with
diff --git a/arch/powerpc/kernel/idle_book3s.S 
b/arch/powerpc/kernel/idle_book3s.S
index d85d5515a091..506b88768767 100644
--- a/arch/powerpc/kernel/idle_book3s.S
+++ b/arch/powerpc/kernel/idle_book3s.S
@@ -1,6 +1,6 @@
 /*
- *  This file contains idle entry/exit functions for POWER7,
- *  POWER8 and POWER9 CPUs.
+ *  This file contains idle entry/exit functions for POWER7 and
+ *  POWER8 CPUs.
  *
  *  This program is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU General Public License
@@ -56,19 +56,8 @@ 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
@@ -85,66 +74,6 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_ARCH_300)
        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
 
 /*
@@ -167,13 +96,23 @@ 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
+ * 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;
+
+/*
+ * Entered with MSR[EE]=0 and no soft-masked interrupts pending.
+ * r3 contains desired idle state (PNV_THREAD_NAP/SLEEP/WINKLE).
  */
-pnv_powersave_common:
+_GLOBAL(power7_idle_insn)
        /* 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
@@ -181,8 +120,6 @@ pnv_powersave_common:
         * 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)
@@ -200,16 +137,7 @@ pnv_powersave_common:
        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
@@ -217,24 +145,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
         */
        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
@@ -321,86 +232,6 @@ enter_winkle:
 
        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) */ \
@@ -419,53 +250,6 @@ ALT_FTR_SECTION_END_NESTED_IFSET(CPU_FTR_ARCH_207S, 66);   
        \
        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
@@ -499,11 +283,7 @@ pnv_powersave_wakeup_mce:
 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)
+       bl      pnv_restore_hyp_resource
 
        li      r0,PNV_THREAD_RUNNING
        stb     r0,PACA_THREAD_IDLE_STATE(r13)  /* Clear thread state */
@@ -535,50 +315,8 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_ARCH_300)
  *
  * 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)
-
+pnv_restore_hyp_resource:
        /*
-        * 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)
@@ -598,15 +336,9 @@ pnv_restore_hyp_resource_arch207:
  * 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:
@@ -621,9 +353,7 @@ pnv_wakeup_tb_loss:
         * 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.
+        * guarantee they will always be restored.
         */
        li      r0,1
        stb     r0,PACA_NAPSTATELOST(r13)
@@ -672,19 +402,16 @@ END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
         * 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):
+        * Check if our thread has a winkle bit set, and set cr4 accordingly.
+        * 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() { }
@@ -749,7 +476,6 @@ BEGIN_FTR_SECTION
 
        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
@@ -815,15 +541,6 @@ timebase_resync:
         * 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)
@@ -845,9 +562,6 @@ common_exit:
 
        /* 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)
 
@@ -861,7 +575,6 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_TYPE_RADIX)
        slbmte  r6,r5
 1:     addi    r8,r8,16
        .endr
-no_segments:
 
        /* Restore per thread state */
 
@@ -884,17 +597,6 @@ no_segments:
        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
diff --git a/arch/powerpc/kernel/idle_isa3.S b/arch/powerpc/kernel/idle_isa3.S
new file mode 100644
index 000000000000..c869512b716a
--- /dev/null
+++ b/arch/powerpc/kernel/idle_isa3.S
@@ -0,0 +1,73 @@
+/*
+ *  This file contains general idle entry/exit functions. The platform / CPU
+ *  must call the correct save/restore functions and ensure SPRs are saved
+ *  and restored correctly, handle KVM, interrupts, etc.
+ *
+ *  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 <asm/ppc_asm.h>
+#include <asm/asm-offsets.h>
+#include <asm/ppc-opcode.h>
+
+/*
+ * Desired PSSCR in r3
+ *
+ * No state will be lost regardless of wakeup mechanism (interrupt or NIA).
+ * Interrupt driven wakeup may clobber volatiles, and should blr (with LR
+ * unchanged) to return to caller with r3 set according to caller's expected
+ * return code (for Book3S/64 that is SRR1).
+ *
+ * Caller is responsible for restoring SPRs, MSR, etc.
+ */
+_GLOBAL(isa3_idle_stop_noloss)
+       mtspr   SPRN_PSSCR,r3
+       PPC_STOP
+       li      r3,0
+       blr
+
+/*
+ * Desired PSSCR in r3
+ *
+ * GPRs may be lost, so they are saved here. Wakeup is by interrupt only.
+ * Wakeup can return to caller by calling pnv_powersave_wakeup_gpr_loss
+ * with r3 set to return value.
+ *
+ * A wakeup without GPR loss may alterateively be handled as in
+ * isa3_idle_stop_noloss as an optimisation.
+ *
+ * Caller is responsible for restoring SPRs, MSR, etc.
+ */
+_GLOBAL(isa3_idle_stop_mayloss)
+       std     r1,PACAR1(r13)
+       mflr    r4
+       mfcr    r5
+       /* use stack red zone rather than a new frame */
+       addi    r6,r1,-INT_FRAME_SIZE
+       SAVE_GPR(2, r6)
+       SAVE_NVGPRS(r6)
+       std     r4,_LINK(r6)
+       std     r5,_CCR(r6)
+       mtspr   SPRN_PSSCR,r3
+       PPC_STOP
+       b       .
+
+/*
+ * Desired return value in r3
+ *
+ * Idle wakeup can call this after calling isa3_idle_stop_loss to
+ * return to caller with r3 as return code.
+ */
+_GLOBAL(isa3_idle_wake_gpr_loss)
+       ld      r1,PACAR1(r13)
+       addi    r6,r1,-INT_FRAME_SIZE
+       ld      r4,_LINK(r6)
+       ld      r5,_CCR(r6)
+       REST_NVGPRS(r6)
+       REST_GPR(2, r6)
+       mtlr    r4
+       mtcr    r5
+       blr
diff --git a/arch/powerpc/kernel/setup-common.c 
b/arch/powerpc/kernel/setup-common.c
index 40b44bb53a4e..e089da156ef3 100644
--- a/arch/powerpc/kernel/setup-common.c
+++ b/arch/powerpc/kernel/setup-common.c
@@ -401,8 +401,8 @@ void __init check_for_initrd(void)
 
 #ifdef CONFIG_SMP
 
-int threads_per_core, threads_per_subcore, threads_shift;
-cpumask_t threads_core_mask;
+int threads_per_core, threads_per_subcore, threads_shift __read_mostly;
+cpumask_t threads_core_mask __read_mostly;
 EXPORT_SYMBOL_GPL(threads_per_core);
 EXPORT_SYMBOL_GPL(threads_per_subcore);
 EXPORT_SYMBOL_GPL(threads_shift);
diff --git a/arch/powerpc/mm/slb.c b/arch/powerpc/mm/slb.c
index cb796724a6fc..2d5db5e0132e 100644
--- a/arch/powerpc/mm/slb.c
+++ b/arch/powerpc/mm/slb.c
@@ -90,7 +90,7 @@ static inline void create_shadowed_slbe(unsigned long ea, int 
ssize,
                     : "memory" );
 }
 
-static void __slb_flush_and_rebolt(void)
+void __slb_flush_and_rebolt(void)
 {
        /* If you change this make sure you change SLB_NUM_BOLTED
         * and PR KVM appropriately too. */
@@ -128,6 +128,8 @@ static void __slb_flush_and_rebolt(void)
                        "r"(ksp_vsid_data),
                        "r"(ksp_esid_data)
                     : "memory");
+
+       get_paca()->slb_cache_ptr = 0;
 }
 
 void slb_flush_and_rebolt(void)
@@ -142,7 +144,6 @@ void slb_flush_and_rebolt(void)
        hard_irq_disable();
 
        __slb_flush_and_rebolt();
-       get_paca()->slb_cache_ptr = 0;
 }
 
 void slb_vmalloc_update(void)
@@ -213,6 +214,7 @@ void switch_slb(struct task_struct *tsk, struct mm_struct 
*mm)
                        asm volatile("slbie %0" : : "r" (slbie_data));
                }
                asm volatile("isync" : : : "memory");
+               get_paca()->slb_cache_ptr = 0;
        } else {
                __slb_flush_and_rebolt();
        }
@@ -221,7 +223,6 @@ void switch_slb(struct task_struct *tsk, struct mm_struct 
*mm)
        if (offset == 1 || offset > SLB_CACHE_ENTRIES)
                asm volatile("slbie %0" : : "r" (slbie_data));
 
-       get_paca()->slb_cache_ptr = 0;
        copy_mm_to_paca(mm);
 
        /*
diff --git a/arch/powerpc/platforms/powernv/idle.c 
b/arch/powerpc/platforms/powernv/idle.c
index 12f13acee1f6..2e129b882727 100644
--- a/arch/powerpc/platforms/powernv/idle.c
+++ b/arch/powerpc/platforms/powernv/idle.c
@@ -16,6 +16,7 @@
 #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>
@@ -46,10 +47,10 @@ static u64 pnv_default_stop_mask;
 static bool default_stop_found;
 
 /*
- * First deep stop state. Used to figure out when to save/restore
- * hypervisor context.
+ * First stop state levels when HV and TB loss can occur.
  */
-u64 pnv_first_deep_stop_state = MAX_STOP_STATE;
+static u64 pnv_first_tb_loss_level = MAX_STOP_STATE + 1;
+static u64 pnv_first_hv_loss_level = MAX_STOP_STATE + 1;
 
 /*
  * psscr value and mask of the deepest stop idle state.
@@ -135,11 +136,11 @@ static int pnv_save_sprs_for_deep_states(void)
        return 0;
 }
 
-static void pnv_alloc_idle_core_states(void)
+static void pnv_alloc_idle_core_states_p8(void)
 {
        int i, j;
        int nr_cores = cpu_nr_cores();
-       u32 *core_idle_state;
+       unsigned long *core_idle_state;
 
        /*
         * core_idle_state - The lower 8 bits track the idle state of
@@ -166,7 +167,7 @@ static void pnv_alloc_idle_core_states(void)
                int node = cpu_to_node(first_cpu);
                size_t paca_ptr_array_size;
 
-               core_idle_state = kmalloc_node(sizeof(u32), GFP_KERNEL, node);
+               core_idle_state = kmalloc_node(sizeof(unsigned long), 
GFP_KERNEL, node);
                *core_idle_state = (1 << threads_per_core) - 1;
                paca_ptr_array_size = (threads_per_core *
                                       sizeof(struct paca_struct *));
@@ -181,41 +182,6 @@ static void pnv_alloc_idle_core_states(void)
        }
 
        update_subcore_sibling_mask();
-
-       if (supported_cpuidle_states & OPAL_PM_LOSE_FULL_CONTEXT) {
-               int rc = pnv_save_sprs_for_deep_states();
-
-               if (likely(!rc))
-                       return;
-
-               /*
-                * 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");
-                       }
-               }
-       }
 }
 
 u32 pnv_get_supported_cpuidle_states(void)
@@ -345,6 +311,263 @@ void power7_idle(void)
        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 mmcra;
+       u32 mmcr0;
+       u32 mmcr1;
+       u64 mmcr2;
+};
+
+static inline void atomic_start_thread_idle(void)
+{
+       int cpu = raw_smp_processor_id();
+       int first = cpu_first_thread_sibling(cpu);
+       int thread = cpu_thread_in_core(cpu);
+       unsigned long *state = &paca_ptrs[first]->idle_state;
+       u64 s = READ_ONCE(*state);
+       u64 new, tmp;
+
+again:
+       if (unlikely(s & PNV_CORE_IDLE_LOCK_BIT)) {
+               spin_begin();
+               do {
+                       spin_cpu_relax();
+                       s = READ_ONCE(*state);
+               } while (s & PNV_CORE_IDLE_LOCK_BIT);
+               spin_end();
+       }
+
+       BUG_ON(!(s & thread));
+
+       new = s & ~thread;
+       tmp = cmpxchg(state, s, new);
+       if (unlikely(tmp != s)) {
+               s = tmp;
+               goto again;
+       }
+}
+
+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_thread_idle(void)
+{
+       int cpu = raw_smp_processor_id();
+       int first = cpu_first_thread_sibling(cpu);
+       unsigned long *state = &paca_ptrs[first]->idle_state;
+
+       clear_bit_unlock(NR_PNV_CORE_IDLE_LOCK_BIT, state);
+}
+
+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);
+       int thread = cpu_thread_in_core(cpu);
+       unsigned long *state = &paca_ptrs[first]->idle_state;
+       unsigned long srr1;
+       unsigned long mmcr0 = 0;
+       struct p9_sprs sprs;
+
+       /* XXX: this gets rid of the uninitialized warning. Should use 
attributes because this is expensive */
+       memset(&sprs, 0, sizeof(sprs));
+
+       if (!(psscr & (PSSCR_EC|PSSCR_ESL))) {
+               /*
+                * Wake synchronously. SRESET via xscom may still cause
+                * a 0x100 powersave wakeup with SRR1 reason!
+                */
+               srr1 = isa3_idle_stop_noloss(psscr);
+               if (likely(!srr1))
+                       return 0;
+
+       } else {
+               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) >= pnv_first_hv_loss_level) {
+                       atomic_start_thread_idle();
+
+                       sprs.ptcr = mfspr(SPRN_PTCR);
+                       sprs.rpr = mfspr(SPRN_RPR);
+                       sprs.tscr = mfspr(SPRN_TSCR);
+                       sprs.ldbar = mfspr(SPRN_LDBAR);
+
+                       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.mmcra = mfspr(SPRN_MMCRA);
+                       sprs.mmcr0 = mfspr(SPRN_MMCR0);
+                       sprs.mmcr1 = mfspr(SPRN_MMCR1);
+                       sprs.mmcr2 = mfspr(SPRN_MMCR2);
+               }
+#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;
+                       }
+
+                       srr1 = isa3_idle_stop_mayloss(psscr);
+                       local_paca->requested_psscr = 0;
+               } else
+#endif
+                       srr1 = isa3_idle_stop_mayloss(psscr);
+       }
+
+       WARN_ON_ONCE(!srr1);
+       WARN_ON_ONCE(mfmsr() & (MSR_IR|MSR_DR));
+
+       if ((srr1 & SRR1_WAKESTATE) != SRR1_WS_NOLOSS) {
+               unsigned long mmcra;
+
+               /*
+                * Workaround for POWER9 DD2, if we lost resources, the ERAT
+                * might have been mixed up 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_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);
+
+       if (likely((srr1 & SRR1_WAKESTATE) != SRR1_WS_HVLOSS)) {
+               mtmsr(MSR_KERNEL);
+               return srr1;
+       }
+
+       /* HV state loss */
+       WARN_ON((psscr & PSSCR_RL_MASK) < pnv_first_hv_loss_level);
+
+       atomic_lock_thread_idle();
+
+       WARN_ON(*state & thread);
+
+       if ((*state & ((1 << threads_per_core) - 1)) != 0)
+               goto core_woken;
+
+       /* Per-core SPRs */
+       mtspr(SPRN_PTCR, sprs.ptcr);
+       mtspr(SPRN_RPR, sprs.rpr);
+       mtspr(SPRN_TSCR, sprs.tscr);
+       mtspr(SPRN_LDBAR, sprs.ldbar);
+
+       if ((psscr & PSSCR_RL_MASK) >= pnv_first_tb_loss_level) {
+               unsigned long level = mfspr(SPRN_PSSCR) & PSSCR_RL_MASK;
+               if (level >= pnv_first_tb_loss_level) {
+                       /* TB loss */
+                       if (opal_resync_timebase() != OPAL_SUCCESS)
+                               BUG();
+               }
+       }
+
+core_woken:
+       *state |= thread;
+       atomic_unlock_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_MMCRA, sprs.mmcra);
+       mtspr(SPRN_MMCR0, sprs.mmcr0);
+       mtspr(SPRN_MMCR1, sprs.mmcr1);
+       mtspr(SPRN_MMCR2, sprs.mmcr2);
+
+       if (!radix_enabled())
+               __slb_flush_and_rebolt();
+
+       mtmsr(MSR_KERNEL);
+
+       return srr1;
+}
+
+unsigned long power9_offline_stop(unsigned long psscr)
+{
+#ifndef CONFIG_KVM_BOOK3S_HV_POSSIBLE
+       return power9_idle_stop(psscr, true);
+#else
+       unsigned long srr1;
+
+       /*
+        * 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.
+        */
+       local_paca->kvm_hstate.hwthread_state = KVM_HWTHREAD_IN_IDLE;
+       srr1 = power9_idle_stop(psscr, false);
+
+       if (local_paca->kvm_hstate.hwthread_state == KVM_HWTHREAD_IN_KERNEL) {
+               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) {
+               /* XXX: fix this so it's not garbage */
+               asm volatile("b kvm_start_guest" ::: "memory");
+       }
+       mtmsr(MSR_KERNEL);
+
+       return srr1;
+#endif
+}
+
 static unsigned long __power9_idle_type(unsigned long stop_psscr_val,
                                      unsigned long stop_psscr_mask)
 {
@@ -358,7 +581,7 @@ static unsigned long __power9_idle_type(unsigned long 
stop_psscr_val,
        psscr = (psscr & ~stop_psscr_mask) | stop_psscr_val;
 
        __ppc64_runlatch_off();
-       srr1 = power9_idle_stop(psscr);
+       srr1 = power9_idle_stop(psscr, true);
        __ppc64_runlatch_on();
 
        fini_irq_for_idle_irqsoff();
@@ -407,7 +630,7 @@ void pnv_power9_force_smt4_catch(void)
                        atomic_inc(&paca_ptrs[cpu0+thr]->dont_stop);
        }
        /* order setting dont_stop vs testing requested_psscr */
-       mb();
+       smp_mb();
        for (thr = 0; thr < threads_per_core; ++thr) {
                if (!paca_ptrs[cpu0+thr]->requested_psscr)
                        ++awake_threads;
@@ -623,7 +846,8 @@ static int __init pnv_power9_idle_init(struct device_node 
*np, u32 *flags,
        u64 *psscr_val = NULL;
        u64 *psscr_mask = NULL;
        u32 *residency_ns = NULL;
-       u64 max_residency_ns = 0;
+       u64 max_deep_residency_ns = 0;
+       u64 max_default_residency_ns = 0;
        int rc = 0, i;
 
        psscr_val = kcalloc(dt_idle_states, sizeof(*psscr_val), GFP_KERNEL);
@@ -661,26 +885,25 @@ static int __init pnv_power9_idle_init(struct device_node 
*np, u32 *flags,
        }
 
        /*
-        * Set pnv_first_deep_stop_state, pnv_deepest_stop_psscr_{val,mask},
-        * and the pnv_default_stop_{val,mask}.
-        *
-        * pnv_first_deep_stop_state should be set to the first stop
-        * level to cause hypervisor state loss.
-        *
         * 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 shallowest (OPAL_PM_STOP_INST_FAST) loss-less stop state.
+        * the deepest loss-less (OPAL_PM_STOP_INST_FAST) stop state.
         */
-       pnv_first_deep_stop_state = MAX_STOP_STATE;
+       pnv_first_tb_loss_level = MAX_STOP_STATE + 1;
+       pnv_first_hv_loss_level = MAX_STOP_STATE + 1;
        for (i = 0; i < dt_idle_states; i++) {
                int err;
                u64 psscr_rl = psscr_val[i] & PSSCR_RL_MASK;
 
+               if ((flags[i] & OPAL_PM_TIMEBASE_STOP) &&
+                    (pnv_first_tb_loss_level > psscr_rl))
+                       pnv_first_tb_loss_level = psscr_rl;
+
                if ((flags[i] & OPAL_PM_LOSE_FULL_CONTEXT) &&
-                    (pnv_first_deep_stop_state > psscr_rl))
-                       pnv_first_deep_stop_state = psscr_rl;
+                    (pnv_first_hv_loss_level > psscr_rl))
+                       pnv_first_hv_loss_level = psscr_rl;
 
                err = validate_psscr_val_mask(&psscr_val[i], &psscr_mask[i],
                                              flags[i]);
@@ -689,19 +912,21 @@ static int __init pnv_power9_idle_init(struct device_node 
*np, u32 *flags,
                        continue;
                }
 
-               if (max_residency_ns < residency_ns[i]) {
-                       max_residency_ns = residency_ns[i];
+               if (max_deep_residency_ns < residency_ns[i]) {
+                       max_deep_residency_ns = residency_ns[i];
                        pnv_deepest_stop_psscr_val = psscr_val[i];
                        pnv_deepest_stop_psscr_mask = psscr_mask[i];
                        pnv_deepest_stop_flag = flags[i];
                        deepest_stop_found = true;
                }
 
-               if (!default_stop_found &&
+               if (max_default_residency_ns < residency_ns[i] &&
                    (flags[i] & OPAL_PM_STOP_INST_FAST)) {
+                       max_default_residency_ns = residency_ns[i];
                        pnv_default_stop_val = psscr_val[i];
                        pnv_default_stop_mask = psscr_mask[i];
                        default_stop_found = true;
+                       WARN_ON(flags[i] & OPAL_PM_LOSE_FULL_CONTEXT);
                }
        }
 
@@ -721,15 +946,48 @@ static int __init pnv_power9_idle_init(struct device_node 
*np, u32 *flags,
                        pnv_deepest_stop_psscr_mask);
        }
 
-       pr_info("cpuidle-powernv: Requested Level (RL) value of first deep stop 
= 0x%llx\n",
-               pnv_first_deep_stop_state);
+       pr_info("cpuidle-powernv: First stop level that may lose SPRs = 
0x%lld\n",
+               pnv_first_hv_loss_level);
+
+       pr_info("cpuidle-powernv: First stop level that may lose timebase = 
0x%lld\n",
+               pnv_first_tb_loss_level);
 out:
        kfree(psscr_val);
        kfree(psscr_mask);
        kfree(residency_ns);
+
        return rc;
 }
 
+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
  */
@@ -771,6 +1029,7 @@ static void __init pnv_probe_idle_states(void)
 out:
        kfree(flags);
 }
+
 static int __init pnv_init_idle_states(void)
 {
 
@@ -798,10 +1057,29 @@ static int __init pnv_init_idle_states(void)
                                &dev_attr_fastsleep_workaround_applyonce);
        }
 
-       pnv_alloc_idle_core_states();
+       if (!cpu_has_feature(CPU_FTR_ARCH_300)) {
+               pnv_alloc_idle_core_states_p8();
+               if (supported_cpuidle_states & OPAL_PM_NAP_ENABLED)
+                       ppc_md.power_save = power7_idle;
+       } else {
+               int cpu;
+
+               for_each_present_cpu(cpu) {
+                       paca_ptrs[cpu]->requested_psscr = 0;
+                       paca_ptrs[cpu]->idle_state = 0;
+                       if (cpu == cpu_first_thread_sibling(cpu))
+                               paca_ptrs[cpu]->idle_state =
+                                       (1 << threads_per_core) - 1;
+#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
+                       atomic_set(&paca_ptrs[cpu]->dont_stop, 0);
+#endif
+               }
+       }
 
-       if (supported_cpuidle_states & OPAL_PM_NAP_ENABLED)
-               ppc_md.power_save = power7_idle;
+       if (supported_cpuidle_states & OPAL_PM_LOSE_FULL_CONTEXT) {
+               if (pnv_save_sprs_for_deep_states())
+                       pnv_disable_deep_states();
+       }
 
 out:
        return 0;
diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c
index 21119cfe8474..09120d4ec12b 100644
--- a/arch/powerpc/xmon/xmon.c
+++ b/arch/powerpc/xmon/xmon.c
@@ -2425,19 +2425,18 @@ static void dump_one_paca(int cpu)
 #endif
 
 #ifdef CONFIG_PPC_POWERNV
-       DUMP(p, core_idle_state_ptr, "%-*px");
-       DUMP(p, thread_idle_state, "%#-*x");
-       DUMP(p, thread_mask, "%#-*x");
-       DUMP(p, subcore_sibling_mask, "%#-*x");
-       DUMP(p, requested_psscr, "%#-*llx");
-       DUMP(p, stop_sprs.pid, "%#-*llx");
-       DUMP(p, stop_sprs.ldbar, "%#-*llx");
-       DUMP(p, stop_sprs.fscr, "%#-*llx");
-       DUMP(p, stop_sprs.hfscr, "%#-*llx");
-       DUMP(p, stop_sprs.mmcr1, "%#-*llx");
-       DUMP(p, stop_sprs.mmcr2, "%#-*llx");
-       DUMP(p, stop_sprs.mmcra, "%#-*llx");
-       DUMP(p, dont_stop.counter, "%#-*x");
+       if (!cpu_has_feature(CPU_FTR_ARCH_300)) {
+               DUMP(p, core_idle_state_ptr, "%-*px");
+               DUMP(p, thread_idle_state, "%#-*x");
+               DUMP(p, thread_mask, "%#-*x");
+               DUMP(p, subcore_sibling_mask, "%#-*x");
+       } else {
+               DUMP(p, idle_state, "%#-*lx");
+               DUMP(p, requested_psscr, "%#-*llx");
+#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
+               DUMP(p, dont_stop.counter, "%#-*x");
+#endif
+       }
 #endif
 
        DUMP(p, accounting.utime, "%#-*lx");
-- 
2.17.0

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