Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64...

[cascardo/linux.git] / arch / powerpc / kernel / exceptions-64s.S

diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index 41091fd..bffec73 100644 (file)
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -144,29 +144,14 @@ machine_check_pSeries_1:
         * vector
         */
        SET_SCRATCH0(r13)               /* save r13 */
-#ifdef CONFIG_PPC_P7_NAP
-BEGIN_FTR_SECTION
-       /* Running native on arch 2.06 or later, check if we are
-        * waking up from nap. We only handle no state loss and
-        * supervisor state loss. We do -not- handle hypervisor
-        * state loss at this time.
+       /*
+        * Running native on arch 2.06 or later, we may wakeup from winkle
+        * inside machine check. If yes, then last bit of HSPGR0 would be set
+        * to 1. Hence clear it unconditionally.
         */
-       mfspr   r13,SPRN_SRR1
-       rlwinm. r13,r13,47-31,30,31
-       OPT_GET_SPR(r13, SPRN_CFAR, CPU_FTR_CFAR)
-       beq     9f
-
-       mfspr   r13,SPRN_SRR1
-       rlwinm. r13,r13,47-31,30,31
-       /* waking up from powersave (nap) state */
-       cmpwi   cr1,r13,2
-       /* Total loss of HV state is fatal. let's just stay stuck here */
-       OPT_GET_SPR(r13, SPRN_CFAR, CPU_FTR_CFAR)
-       bgt     cr1,.
-9:
-       OPT_SET_SPR(r13, SPRN_CFAR, CPU_FTR_CFAR)
-END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)
-#endif /* CONFIG_PPC_P7_NAP */
+       GET_PACA(r13)
+       clrrdi  r13,r13,1
+       SET_PACA(r13)
        EXCEPTION_PROLOG_0(PACA_EXMC)
 BEGIN_FTR_SECTION
        b       machine_check_powernv_early
@@ -500,7 +485,23 @@ machine_check_fwnmi:
        EXCEPTION_PROLOG_0(PACA_EXMC)
 machine_check_pSeries_0:
        EXCEPTION_PROLOG_1(PACA_EXMC, KVMTEST, 0x200)
-       EXCEPTION_PROLOG_PSERIES_1(machine_check_common, EXC_STD)
+       /*
+        * The following is essentially EXCEPTION_PROLOG_PSERIES_1 with the
+        * difference that MSR_RI is not enabled, because PACA_EXMC is being
+        * used, so nested machine check corrupts it. machine_check_common
+        * enables MSR_RI.
+        */
+       ld      r12,PACAKBASE(r13)
+       ld      r10,PACAKMSR(r13)
+       xori    r10,r10,MSR_RI
+       mfspr   r11,SPRN_SRR0
+       LOAD_HANDLER(r12, machine_check_common)
+       mtspr   SPRN_SRR0,r12
+       mfspr   r12,SPRN_SRR1
+       mtspr   SPRN_SRR1,r10
+       rfid
+       b       .       /* prevent speculative execution */
+
        KVM_HANDLER_SKIP(PACA_EXMC, EXC_STD, 0x200)
        KVM_HANDLER_SKIP(PACA_EXGEN, EXC_STD, 0x300)
        KVM_HANDLER_SKIP(PACA_EXSLB, EXC_STD, 0x380)
@@ -984,14 +985,17 @@ ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_TYPE_RADIX)
 machine_check_common:
 
        mfspr   r10,SPRN_DAR
-       std     r10,PACA_EXGEN+EX_DAR(r13)
+       std     r10,PACA_EXMC+EX_DAR(r13)
        mfspr   r10,SPRN_DSISR
-       stw     r10,PACA_EXGEN+EX_DSISR(r13)
+       stw     r10,PACA_EXMC+EX_DSISR(r13)
        EXCEPTION_PROLOG_COMMON(0x200, PACA_EXMC)
        FINISH_NAP
        RECONCILE_IRQ_STATE(r10, r11)
-       ld      r3,PACA_EXGEN+EX_DAR(r13)
-       lwz     r4,PACA_EXGEN+EX_DSISR(r13)
+       ld      r3,PACA_EXMC+EX_DAR(r13)
+       lwz     r4,PACA_EXMC+EX_DSISR(r13)
+       /* Enable MSR_RI when finished with PACA_EXMC */
+       li      r10,MSR_RI
+       mtmsrd  r10,1
        std     r3,_DAR(r1)
        std     r4,_DSISR(r1)
        bl      save_nvgprs
@@ -1273,25 +1277,51 @@ machine_check_handle_early:
         * Check if thread was in power saving mode. We come here when any
         * of the following is true:
         * a. thread wasn't in power saving mode
-        * b. thread was in power saving mode with no state loss or
-        *    supervisor state loss
+        * b. thread was in power saving mode with no state loss,
+        *    supervisor state loss or hypervisor state loss.
         *
-        * Go back to nap again if (b) is true.
+        * Go back to nap/sleep/winkle mode again if (b) is true.
         */
        rlwinm. r11,r12,47-31,30,31     /* Was it in power saving mode? */
        beq     4f                      /* No, it wasn;t */
        /* Thread was in power saving mode. Go back to nap again. */
        cmpwi   r11,2
-       bne     3f
-       /* Supervisor state loss */
+       blt     3f
+       /* Supervisor/Hypervisor state loss */
        li      r0,1
        stb     r0,PACA_NAPSTATELOST(r13)
 3:     bl      machine_check_queue_event
        MACHINE_CHECK_HANDLER_WINDUP
        GET_PACA(r13)
        ld      r1,PACAR1(r13)
-       li      r3,PNV_THREAD_NAP
-       b       pnv_enter_arch207_idle_mode
+       /*
+        * Check what idle state this CPU was in and go back to same mode
+        * again.
+        */
+       lbz     r3,PACA_THREAD_IDLE_STATE(r13)
+       cmpwi   r3,PNV_THREAD_NAP
+       bgt     10f
+       IDLE_STATE_ENTER_SEQ(PPC_NAP)
+       /* No return */
+10:
+       cmpwi   r3,PNV_THREAD_SLEEP
+       bgt     2f
+       IDLE_STATE_ENTER_SEQ(PPC_SLEEP)
+       /* No return */
+
+2:
+       /*
+        * Go back to winkle. Please note that this thread was woken up in
+        * machine check from winkle and have not restored the per-subcore
+        * state. Hence before going back to winkle, set last bit of HSPGR0
+        * to 1. This will make sure that if this thread gets woken up
+        * again at reset vector 0x100 then it will get chance to restore
+        * the subcore state.
+        */
+       ori     r13,r13,1
+       SET_PACA(r13)
+       IDLE_STATE_ENTER_SEQ(PPC_WINKLE)
+       /* No return */
 4:
 #endif
        /*