diff options
Diffstat (limited to 'arch/powerpc/kvm/book3s_rmhandlers.S')
| -rw-r--r-- | arch/powerpc/kvm/book3s_rmhandlers.S | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/arch/powerpc/kvm/book3s_rmhandlers.S b/arch/powerpc/kvm/book3s_rmhandlers.S new file mode 100644 index 000000000..0a557ffca --- /dev/null +++ b/arch/powerpc/kvm/book3s_rmhandlers.S @@ -0,0 +1,163 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * + * Copyright SUSE Linux Products GmbH 2009 + * + * Authors: Alexander Graf <agraf@suse.de> + */ + +#include <asm/ppc_asm.h> +#include <asm/kvm_asm.h> +#include <asm/reg.h> +#include <asm/mmu.h> +#include <asm/page.h> +#include <asm/asm-offsets.h> +#include <asm/asm-compat.h> + +#ifdef CONFIG_PPC_BOOK3S_64 +#include <asm/exception-64s.h> +#endif + +/***************************************************************************** + * * + * Real Mode handlers that need to be in low physical memory * + * * + ****************************************************************************/ + +#if defined(CONFIG_PPC_BOOK3S_64) + +#ifdef CONFIG_PPC64_ELF_ABI_V2 +#define FUNC(name) name +#else +#define FUNC(name) GLUE(.,name) +#endif + +#elif defined(CONFIG_PPC_BOOK3S_32) + +#define FUNC(name) name + +#define RFI_TO_KERNEL rfi +#define RFI_TO_GUEST rfi + +.macro INTERRUPT_TRAMPOLINE intno + +.global kvmppc_trampoline_\intno +kvmppc_trampoline_\intno: + + mtspr SPRN_SPRG_SCRATCH0, r13 /* Save r13 */ + + /* + * First thing to do is to find out if we're coming + * from a KVM guest or a Linux process. + * + * To distinguish, we check a magic byte in the PACA/current + */ + mfspr r13, SPRN_SPRG_THREAD + lwz r13, THREAD_KVM_SVCPU(r13) + /* PPC32 can have a NULL pointer - let's check for that */ + mtspr SPRN_SPRG_SCRATCH1, r12 /* Save r12 */ + mfcr r12 + cmpwi r13, 0 + bne 1f +2: mtcr r12 + mfspr r12, SPRN_SPRG_SCRATCH1 + mfspr r13, SPRN_SPRG_SCRATCH0 /* r13 = original r13 */ + b kvmppc_resume_\intno /* Get back original handler */ + +1: tophys(r13, r13) + stw r12, HSTATE_SCRATCH1(r13) + mfspr r12, SPRN_SPRG_SCRATCH1 + stw r12, HSTATE_SCRATCH0(r13) + lbz r12, HSTATE_IN_GUEST(r13) + cmpwi r12, KVM_GUEST_MODE_NONE + bne ..kvmppc_handler_hasmagic_\intno + /* No KVM guest? Then jump back to the Linux handler! */ + lwz r12, HSTATE_SCRATCH1(r13) + b 2b + + /* Now we know we're handling a KVM guest */ +..kvmppc_handler_hasmagic_\intno: + + /* Should we just skip the faulting instruction? */ + cmpwi r12, KVM_GUEST_MODE_SKIP + beq kvmppc_handler_skip_ins + + /* Let's store which interrupt we're handling */ + li r12, \intno + + /* Jump into the SLB exit code that goes to the highmem handler */ + b kvmppc_handler_trampoline_exit + +.endm + +INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_SYSTEM_RESET +INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_MACHINE_CHECK +INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_DATA_STORAGE +INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_INST_STORAGE +INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_EXTERNAL +INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_ALIGNMENT +INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_PROGRAM +INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_FP_UNAVAIL +INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_DECREMENTER +INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_SYSCALL +INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_TRACE +INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_PERFMON +INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_ALTIVEC + +/* + * Bring us back to the faulting code, but skip the + * faulting instruction. + * + * This is a generic exit path from the interrupt + * trampolines above. + * + * Input Registers: + * + * R12 = free + * R13 = Shadow VCPU (PACA) + * HSTATE.SCRATCH0 = guest R12 + * HSTATE.SCRATCH1 = guest CR + * SPRG_SCRATCH0 = guest R13 + * + */ +kvmppc_handler_skip_ins: + + /* Patch the IP to the next instruction */ + /* Note that prefixed instructions are disabled in PR KVM for now */ + mfsrr0 r12 + addi r12, r12, 4 + mtsrr0 r12 + + /* Clean up all state */ + lwz r12, HSTATE_SCRATCH1(r13) + mtcr r12 + PPC_LL r12, HSTATE_SCRATCH0(r13) + GET_SCRATCH0(r13) + + /* And get back into the code */ + RFI_TO_KERNEL +#endif + +/* + * Call kvmppc_handler_trampoline_enter in real mode + * + * On entry, r4 contains the guest shadow MSR + * MSR.EE has to be 0 when calling this function + */ +_GLOBAL_TOC(kvmppc_entry_trampoline) + mfmsr r5 + LOAD_REG_ADDR(r7, kvmppc_handler_trampoline_enter) + toreal(r7) + + li r6, MSR_IR | MSR_DR + andc r6, r5, r6 /* Clear DR and IR in MSR value */ + /* + * Set EE in HOST_MSR so that it's enabled when we get into our + * C exit handler function. + */ + ori r5, r5, MSR_EE + mtsrr0 r7 + mtsrr1 r6 + RFI_TO_KERNEL + +#include "book3s_segment.S" |