KVM: PPC: Fix PR KVM on POWER7 bare metal
[linux-flexiantxendom0-3.2.10.git] / arch / powerpc / kvm / book3s_segment.S
index 4c0d1d8..87cfc1d 100644 (file)
@@ -22,7 +22,8 @@
 #if defined(CONFIG_PPC_BOOK3S_64)
 
 #define GET_SHADOW_VCPU(reg)    \
-       addi    reg, r13, PACA_KVM_SVCPU
+       mr      reg, r13
+#define MTMSR_EERI(reg)                mtmsrd  (reg),1
 
 #elif defined(CONFIG_PPC_BOOK3S_32)
 
@@ -30,6 +31,7 @@
        tophys(reg, r2);                        \
        lwz     reg, (THREAD + THREAD_KVM_SVCPU)(reg);  \
        tophys(reg, reg)
+#define MTMSR_EERI(reg)                mtmsr   (reg)
 
 #endif
 
@@ -57,10 +59,12 @@ kvmppc_handler_trampoline_enter:
        /* Required state:
         *
         * MSR = ~IR|DR
-        * R13 = PACA
         * R1 = host R1
         * R2 = host R2
-        * R10 = guest MSR
+        * R4 = guest shadow MSR
+        * R5 = normal host MSR
+        * R6 = current host MSR (EE, IR, DR off)
+        * LR = highmem guest exit code
         * all other volatile GPRS = free
         * SVCPU[CR] = guest CR
         * SVCPU[XER] = guest XER
@@ -71,43 +75,76 @@ kvmppc_handler_trampoline_enter:
        /* r3 = shadow vcpu */
        GET_SHADOW_VCPU(r3)
 
-       /* Move SRR0 and SRR1 into the respective regs */
-       PPC_LL  r9, SVCPU_PC(r3)
-       mtsrr0  r9
-       mtsrr1  r10
+       /* Save guest exit handler address and MSR */
+       mflr    r0
+       PPC_STL r0, HSTATE_VMHANDLER(r3)
+       PPC_STL r5, HSTATE_HOST_MSR(r3)
+
+       /* Save R1/R2 in the PACA (64-bit) or shadow_vcpu (32-bit) */
+       PPC_STL r1, HSTATE_HOST_R1(r3)
+       PPC_STL r2, HSTATE_HOST_R2(r3)
 
        /* Activate guest mode, so faults get handled by KVM */
        li      r11, KVM_GUEST_MODE_GUEST
-       stb     r11, SVCPU_IN_GUEST(r3)
+       stb     r11, HSTATE_IN_GUEST(r3)
 
        /* Switch to guest segment. This is subarch specific. */
        LOAD_GUEST_SEGMENTS
 
+#ifdef CONFIG_PPC_BOOK3S_64
+       /* Some guests may need to have dcbz set to 32 byte length.
+        *
+        * Usually we ensure that by patching the guest's instructions
+        * to trap on dcbz and emulate it in the hypervisor.
+        *
+        * If we can, we should tell the CPU to use 32 byte dcbz though,
+        * because that's a lot faster.
+        */
+       lbz     r0, HSTATE_RESTORE_HID5(r3)
+       cmpwi   r0, 0
+       beq     no_dcbz32_on
+
+       mfspr   r0,SPRN_HID5
+       ori     r0, r0, 0x80            /* XXX HID5_dcbz32 = 0x80 */
+       mtspr   SPRN_HID5,r0
+no_dcbz32_on:
+
+#endif /* CONFIG_PPC_BOOK3S_64 */
+
        /* Enter guest */
 
-       PPC_LL  r4, (SVCPU_CTR)(r3)
-       PPC_LL  r5, (SVCPU_LR)(r3)
-       lwz     r6, (SVCPU_CR)(r3)
-       lwz     r7, (SVCPU_XER)(r3)
-
-       mtctr   r4
-       mtlr    r5
-       mtcr    r6
-       mtxer   r7
-
-       PPC_LL  r0, (SVCPU_R0)(r3)
-       PPC_LL  r1, (SVCPU_R1)(r3)
-       PPC_LL  r2, (SVCPU_R2)(r3)
-       PPC_LL  r4, (SVCPU_R4)(r3)
-       PPC_LL  r5, (SVCPU_R5)(r3)
-       PPC_LL  r6, (SVCPU_R6)(r3)
-       PPC_LL  r7, (SVCPU_R7)(r3)
-       PPC_LL  r8, (SVCPU_R8)(r3)
-       PPC_LL  r9, (SVCPU_R9)(r3)
-       PPC_LL  r10, (SVCPU_R10)(r3)
-       PPC_LL  r11, (SVCPU_R11)(r3)
-       PPC_LL  r12, (SVCPU_R12)(r3)
-       PPC_LL  r13, (SVCPU_R13)(r3)
+       PPC_LL  r8, SVCPU_CTR(r3)
+       PPC_LL  r9, SVCPU_LR(r3)
+       lwz     r10, SVCPU_CR(r3)
+       lwz     r11, SVCPU_XER(r3)
+
+       mtctr   r8
+       mtlr    r9
+       mtcr    r10
+       mtxer   r11
+
+       /* Move SRR0 and SRR1 into the respective regs */
+       PPC_LL  r9, SVCPU_PC(r3)
+       /* First clear RI in our current MSR value */
+       li      r0, MSR_RI
+       andc    r6, r6, r0
+       MTMSR_EERI(r6)
+       mtsrr0  r9
+       mtsrr1  r4
+
+       PPC_LL  r0, SVCPU_R0(r3)
+       PPC_LL  r1, SVCPU_R1(r3)
+       PPC_LL  r2, SVCPU_R2(r3)
+       PPC_LL  r4, SVCPU_R4(r3)
+       PPC_LL  r5, SVCPU_R5(r3)
+       PPC_LL  r6, SVCPU_R6(r3)
+       PPC_LL  r7, SVCPU_R7(r3)
+       PPC_LL  r8, SVCPU_R8(r3)
+       PPC_LL  r9, SVCPU_R9(r3)
+       PPC_LL  r10, SVCPU_R10(r3)
+       PPC_LL  r11, SVCPU_R11(r3)
+       PPC_LL  r12, SVCPU_R12(r3)
+       PPC_LL  r13, SVCPU_R13(r3)
 
        PPC_LL  r3, (SVCPU_R3)(r3)
 
@@ -125,50 +162,64 @@ kvmppc_handler_trampoline_enter_end:
 .global kvmppc_handler_trampoline_exit
 kvmppc_handler_trampoline_exit:
 
+.global kvmppc_interrupt
+kvmppc_interrupt:
+
        /* Register usage at this point:
         *
         * SPRG_SCRATCH0  = guest R13
         * R12            = exit handler id
-        * R13            = shadow vcpu - SHADOW_VCPU_OFF [=PACA on PPC64]
-        * SVCPU.SCRATCH0 = guest R12
-        * SVCPU.SCRATCH1 = guest CR
+        * R13            = shadow vcpu (32-bit) or PACA (64-bit)
+        * HSTATE.SCRATCH0 = guest R12
+        * HSTATE.SCRATCH1 = guest CR
         *
         */
 
        /* Save registers */
 
-       PPC_STL r0, (SHADOW_VCPU_OFF + SVCPU_R0)(r13)
-       PPC_STL r1, (SHADOW_VCPU_OFF + SVCPU_R1)(r13)
-       PPC_STL r2, (SHADOW_VCPU_OFF + SVCPU_R2)(r13)
-       PPC_STL r3, (SHADOW_VCPU_OFF + SVCPU_R3)(r13)
-       PPC_STL r4, (SHADOW_VCPU_OFF + SVCPU_R4)(r13)
-       PPC_STL r5, (SHADOW_VCPU_OFF + SVCPU_R5)(r13)
-       PPC_STL r6, (SHADOW_VCPU_OFF + SVCPU_R6)(r13)
-       PPC_STL r7, (SHADOW_VCPU_OFF + SVCPU_R7)(r13)
-       PPC_STL r8, (SHADOW_VCPU_OFF + SVCPU_R8)(r13)
-       PPC_STL r9, (SHADOW_VCPU_OFF + SVCPU_R9)(r13)
-       PPC_STL r10, (SHADOW_VCPU_OFF + SVCPU_R10)(r13)
-       PPC_STL r11, (SHADOW_VCPU_OFF + SVCPU_R11)(r13)
+       PPC_STL r0, SVCPU_R0(r13)
+       PPC_STL r1, SVCPU_R1(r13)
+       PPC_STL r2, SVCPU_R2(r13)
+       PPC_STL r3, SVCPU_R3(r13)
+       PPC_STL r4, SVCPU_R4(r13)
+       PPC_STL r5, SVCPU_R5(r13)
+       PPC_STL r6, SVCPU_R6(r13)
+       PPC_STL r7, SVCPU_R7(r13)
+       PPC_STL r8, SVCPU_R8(r13)
+       PPC_STL r9, SVCPU_R9(r13)
+       PPC_STL r10, SVCPU_R10(r13)
+       PPC_STL r11, SVCPU_R11(r13)
 
        /* Restore R1/R2 so we can handle faults */
-       PPC_LL  r1, (SHADOW_VCPU_OFF + SVCPU_HOST_R1)(r13)
-       PPC_LL  r2, (SHADOW_VCPU_OFF + SVCPU_HOST_R2)(r13)
+       PPC_LL  r1, HSTATE_HOST_R1(r13)
+       PPC_LL  r2, HSTATE_HOST_R2(r13)
 
        /* Save guest PC and MSR */
-       mfsrr0  r3
+#ifdef CONFIG_PPC64
+BEGIN_FTR_SECTION
+       mr      r10, r12
+       andi.   r0,r12,0x2
+       beq     1f
+       mfspr   r3,SPRN_HSRR0
+       mfspr   r4,SPRN_HSRR1
+       andi.   r12,r12,0x3ffd
+       b       2f
+END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
+#endif
+1:     mfsrr0  r3
        mfsrr1  r4
-
-       PPC_STL r3, (SHADOW_VCPU_OFF + SVCPU_PC)(r13)
-       PPC_STL r4, (SHADOW_VCPU_OFF + SVCPU_SHADOW_SRR1)(r13)
+2:
+       PPC_STL r3, SVCPU_PC(r13)
+       PPC_STL r4, SVCPU_SHADOW_SRR1(r13)
 
        /* Get scratch'ed off registers */
-       mfspr   r9, SPRN_SPRG_SCRATCH0
-       PPC_LL  r8, (SHADOW_VCPU_OFF + SVCPU_SCRATCH0)(r13)
-       lwz     r7, (SHADOW_VCPU_OFF + SVCPU_SCRATCH1)(r13)
+       GET_SCRATCH0(r9)
+       PPC_LL  r8, HSTATE_SCRATCH0(r13)
+       lwz     r7, HSTATE_SCRATCH1(r13)
 
-       PPC_STL r9, (SHADOW_VCPU_OFF + SVCPU_R13)(r13)
-       PPC_STL r8, (SHADOW_VCPU_OFF + SVCPU_R12)(r13)
-       stw     r7, (SHADOW_VCPU_OFF + SVCPU_CR)(r13)
+       PPC_STL r9, SVCPU_R13(r13)
+       PPC_STL r8, SVCPU_R12(r13)
+       stw     r7, SVCPU_CR(r13)
 
        /* Save more register state  */
 
@@ -178,11 +229,11 @@ kvmppc_handler_trampoline_exit:
        mfctr   r8
        mflr    r9
 
-       stw     r5, (SHADOW_VCPU_OFF + SVCPU_XER)(r13)
-       PPC_STL r6, (SHADOW_VCPU_OFF + SVCPU_FAULT_DAR)(r13)
-       stw     r7, (SHADOW_VCPU_OFF + SVCPU_FAULT_DSISR)(r13)
-       PPC_STL r8, (SHADOW_VCPU_OFF + SVCPU_CTR)(r13)
-       PPC_STL r9, (SHADOW_VCPU_OFF + SVCPU_LR)(r13)
+       stw     r5, SVCPU_XER(r13)
+       PPC_STL r6, SVCPU_FAULT_DAR(r13)
+       stw     r7, SVCPU_FAULT_DSISR(r13)
+       PPC_STL r8, SVCPU_CTR(r13)
+       PPC_STL r9, SVCPU_LR(r13)
 
        /*
         * In order for us to easily get the last instruction,
@@ -196,9 +247,22 @@ kvmppc_handler_trampoline_exit:
        beq     ld_last_inst
        cmpwi   r12, BOOK3S_INTERRUPT_PROGRAM
        beq     ld_last_inst
+       cmpwi   r12, BOOK3S_INTERRUPT_SYSCALL
+       beq     ld_last_prev_inst
+       cmpwi   r12, BOOK3S_INTERRUPT_ALIGNMENT
+       beq-    ld_last_inst
+#ifdef CONFIG_PPC64
+BEGIN_FTR_SECTION
+       cmpwi   r12, BOOK3S_INTERRUPT_H_EMUL_ASSIST
+       beq-    ld_last_inst
+END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
+#endif
 
        b       no_ld_last_inst
 
+ld_last_prev_inst:
+       addi    r3, r3, -4
+
 ld_last_inst:
        /* Save off the guest instruction we're at */
 
@@ -210,7 +274,7 @@ ld_last_inst:
        /* Set guest mode to 'jump over instruction' so if lwz faults
         * we'll just continue at the next IP. */
        li      r9, KVM_GUEST_MODE_SKIP
-       stb     r9, (SHADOW_VCPU_OFF + SVCPU_IN_GUEST)(r13)
+       stb     r9, HSTATE_IN_GUEST(r13)
 
        /*    1) enable paging for data */
        mfmsr   r9
@@ -224,34 +288,81 @@ ld_last_inst:
        sync
 
 #endif
-       stw     r0, (SHADOW_VCPU_OFF + SVCPU_LAST_INST)(r13)
+       stw     r0, SVCPU_LAST_INST(r13)
 
 no_ld_last_inst:
 
        /* Unset guest mode */
        li      r9, KVM_GUEST_MODE_NONE
-       stb     r9, (SHADOW_VCPU_OFF + SVCPU_IN_GUEST)(r13)
+       stb     r9, HSTATE_IN_GUEST(r13)
 
        /* Switch back to host MMU */
        LOAD_HOST_SEGMENTS
 
+#ifdef CONFIG_PPC_BOOK3S_64
+
+       lbz     r5, HSTATE_RESTORE_HID5(r13)
+       cmpwi   r5, 0
+       beq     no_dcbz32_off
+
+       li      r4, 0
+       mfspr   r5,SPRN_HID5
+       rldimi  r5,r4,6,56
+       mtspr   SPRN_HID5,r5
+
+no_dcbz32_off:
+
+#endif /* CONFIG_PPC_BOOK3S_64 */
+
+       /*
+        * For some interrupts, we need to call the real Linux
+        * handler, so it can do work for us. This has to happen
+        * as if the interrupt arrived from the kernel though,
+        * so let's fake it here where most state is restored.
+        *
+        * Having set up SRR0/1 with the address where we want
+        * to continue with relocation on (potentially in module
+        * space), we either just go straight there with rfi[d],
+        * or we jump to an interrupt handler if there is an
+        * interrupt to be handled first.  In the latter case,
+        * the rfi[d] at the end of the interrupt handler will
+        * get us back to where we want to continue.
+        */
+
        /* Register usage at this point:
         *
         * R1       = host R1
         * R2       = host R2
+        * R10      = raw exit handler id
         * R12      = exit handler id
-        * R13      = shadow vcpu - SHADOW_VCPU_OFF [=PACA on PPC64]
+        * R13      = shadow vcpu (32-bit) or PACA (64-bit)
         * SVCPU.*  = guest *
         *
         */
 
-       /* RFI into the highmem handler */
-       mfmsr   r7
-       ori     r7, r7, MSR_IR|MSR_DR|MSR_RI|MSR_ME     /* Enable paging */
-       mtsrr1  r7
+       PPC_LL  r6, HSTATE_HOST_MSR(r13)
+       PPC_LL  r8, HSTATE_VMHANDLER(r13)
+
+#ifdef CONFIG_PPC64
+BEGIN_FTR_SECTION
+       andi.   r0,r10,0x2
+       beq     1f
+       mtspr   SPRN_HSRR1, r6
+       mtspr   SPRN_HSRR0, r8
+END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
+#endif
+1:     /* Restore host msr -> SRR1 */
+       mtsrr1  r6
        /* Load highmem handler address */
-       PPC_LL  r8, (SHADOW_VCPU_OFF + SVCPU_VMHANDLER)(r13)
        mtsrr0  r8
 
+       /* RFI into the highmem handler, or jump to interrupt handler */
+       cmpwi   r12, BOOK3S_INTERRUPT_EXTERNAL
+       beqa    BOOK3S_INTERRUPT_EXTERNAL
+       cmpwi   r12, BOOK3S_INTERRUPT_DECREMENTER
+       beqa    BOOK3S_INTERRUPT_DECREMENTER
+       cmpwi   r12, BOOK3S_INTERRUPT_PERFMON
+       beqa    BOOK3S_INTERRUPT_PERFMON
+
        RFI
 kvmppc_handler_trampoline_exit_end: