diff options
Diffstat (limited to 'arch/powerpc/kvm/book3s_rmhandlers.S')
| -rw-r--r-- | arch/powerpc/kvm/book3s_rmhandlers.S | 251 |
1 files changed, 251 insertions, 0 deletions
diff --git a/arch/powerpc/kvm/book3s_rmhandlers.S b/arch/powerpc/kvm/book3s_rmhandlers.S new file mode 100644 index 00000000000..506d5c316c9 --- /dev/null +++ b/arch/powerpc/kvm/book3s_rmhandlers.S @@ -0,0 +1,251 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License, version 2, as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * + * 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/page.h> +#include <asm/asm-offsets.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) + +#define LOAD_SHADOW_VCPU(reg) \ + mfspr reg, SPRN_SPRG_PACA + +#define SHADOW_VCPU_OFF PACA_KVM_SVCPU +#define MSR_NOIRQ MSR_KERNEL & ~(MSR_IR | MSR_DR) +#define FUNC(name) GLUE(.,name) + +#elif defined(CONFIG_PPC_BOOK3S_32) + +#define LOAD_SHADOW_VCPU(reg) \ + mfspr reg, SPRN_SPRG_THREAD; \ + lwz reg, THREAD_KVM_SVCPU(reg); \ + /* PPC32 can have a NULL pointer - let's check for that */ \ + mtspr SPRN_SPRG_SCRATCH1, r12; /* Save r12 */ \ + mfcr r12; \ + cmpwi reg, 0; \ + bne 1f; \ + mfspr reg, SPRN_SPRG_SCRATCH0; \ + mtcr r12; \ + mfspr r12, SPRN_SPRG_SCRATCH1; \ + b kvmppc_resume_\intno; \ +1:; \ + mtcr r12; \ + mfspr r12, SPRN_SPRG_SCRATCH1; \ + tophys(reg, reg) + +#define SHADOW_VCPU_OFF 0 +#define MSR_NOIRQ MSR_KERNEL +#define FUNC(name) name + +#endif + +.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 + */ + LOAD_SHADOW_VCPU(r13) + PPC_STL r12, (SHADOW_VCPU_OFF + SVCPU_SCRATCH0)(r13) + mfcr r12 + stw r12, (SHADOW_VCPU_OFF + SVCPU_SCRATCH1)(r13) + lbz r12, (SHADOW_VCPU_OFF + SVCPU_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, (SHADOW_VCPU_OFF + SVCPU_SCRATCH1)(r13) + mtcr r12 + PPC_LL r12, (SHADOW_VCPU_OFF + SVCPU_SCRATCH0)(r13) + mfspr r13, SPRN_SPRG_SCRATCH0 /* r13 = original r13 */ + b kvmppc_resume_\intno /* Get back original handler */ + + /* 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 + +/* Those are only available on 64 bit machines */ + +#ifdef CONFIG_PPC_BOOK3S_64 +INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_DATA_SEGMENT +INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_INST_SEGMENT +INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_VSX +#endif + +/* + * 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) + * SVCPU.SCRATCH0 = guest R12 + * SVCPU.SCRATCH1 = guest CR + * SPRG_SCRATCH0 = guest R13 + * + */ +kvmppc_handler_skip_ins: + + /* Patch the IP to the next instruction */ + mfsrr0 r12 + addi r12, r12, 4 + mtsrr0 r12 + + /* Clean up all state */ + lwz r12, (SHADOW_VCPU_OFF + SVCPU_SCRATCH1)(r13) + mtcr r12 + PPC_LL r12, (SHADOW_VCPU_OFF + SVCPU_SCRATCH0)(r13) + mfspr r13, SPRN_SPRG_SCRATCH0 + + /* And get back into the code */ + RFI + +/* + * This trampoline brings us back to a real mode handler + * + * Input Registers: + * + * R5 = SRR0 + * R6 = SRR1 + * LR = real-mode IP + * + */ +.global kvmppc_handler_lowmem_trampoline +kvmppc_handler_lowmem_trampoline: + + mtsrr0 r5 + mtsrr1 r6 + blr +kvmppc_handler_lowmem_trampoline_end: + +/* + * Call a function in real mode + * + * Input Registers: + * + * R3 = function + * R4 = MSR + * R5 = scratch register + * + */ +_GLOBAL(kvmppc_rmcall) + LOAD_REG_IMMEDIATE(r5, MSR_NOIRQ) + mtmsr r5 /* Disable relocation and interrupts, so mtsrr + doesn't get interrupted */ + sync + mtsrr0 r3 + mtsrr1 r4 + RFI + +#if defined(CONFIG_PPC_BOOK3S_32) +#define STACK_LR INT_FRAME_SIZE+4 +#elif defined(CONFIG_PPC_BOOK3S_64) +#define STACK_LR _LINK +#endif + +/* + * Activate current's external feature (FPU/Altivec/VSX) + */ +#define define_load_up(what) \ + \ +_GLOBAL(kvmppc_load_up_ ## what); \ + PPC_STLU r1, -INT_FRAME_SIZE(r1); \ + mflr r3; \ + PPC_STL r3, STACK_LR(r1); \ + PPC_STL r20, _NIP(r1); \ + mfmsr r20; \ + LOAD_REG_IMMEDIATE(r3, MSR_DR|MSR_EE); \ + andc r3,r20,r3; /* Disable DR,EE */ \ + mtmsr r3; \ + sync; \ + \ + bl FUNC(load_up_ ## what); \ + \ + mtmsr r20; /* Enable DR,EE */ \ + sync; \ + PPC_LL r3, STACK_LR(r1); \ + PPC_LL r20, _NIP(r1); \ + mtlr r3; \ + addi r1, r1, INT_FRAME_SIZE; \ + blr + +define_load_up(fpu) +#ifdef CONFIG_ALTIVEC +define_load_up(altivec) +#endif +#ifdef CONFIG_VSX +define_load_up(vsx) +#endif + +.global kvmppc_trampoline_lowmem +kvmppc_trampoline_lowmem: + .long kvmppc_handler_lowmem_trampoline - CONFIG_KERNEL_START + +.global kvmppc_trampoline_enter +kvmppc_trampoline_enter: + .long kvmppc_handler_trampoline_enter - CONFIG_KERNEL_START + +#include "book3s_segment.S" |