diff options
Diffstat (limited to 'arch/powerpc/kvm/book3s_64_interrupts.S')
| -rw-r--r-- | arch/powerpc/kvm/book3s_64_interrupts.S | 392 |
1 files changed, 392 insertions, 0 deletions
diff --git a/arch/powerpc/kvm/book3s_64_interrupts.S b/arch/powerpc/kvm/book3s_64_interrupts.S new file mode 100644 index 000000000000..7b55d8094c8b --- /dev/null +++ b/arch/powerpc/kvm/book3s_64_interrupts.S @@ -0,0 +1,392 @@ +/* + * 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> +#include <asm/exception-64s.h> + +#define KVMPPC_HANDLE_EXIT .kvmppc_handle_exit +#define ULONG_SIZE 8 +#define VCPU_GPR(n) (VCPU_GPRS + (n * ULONG_SIZE)) + +.macro mfpaca tmp_reg, src_reg, offset, vcpu_reg + ld \tmp_reg, (PACA_EXMC+\offset)(r13) + std \tmp_reg, VCPU_GPR(\src_reg)(\vcpu_reg) +.endm + +.macro DISABLE_INTERRUPTS + mfmsr r0 + rldicl r0,r0,48,1 + rotldi r0,r0,16 + mtmsrd r0,1 +.endm + +/***************************************************************************** + * * + * Guest entry / exit code that is in kernel module memory (highmem) * + * * + ****************************************************************************/ + +/* Registers: + * r3: kvm_run pointer + * r4: vcpu pointer + */ +_GLOBAL(__kvmppc_vcpu_entry) + +kvm_start_entry: + /* Write correct stack frame */ + mflr r0 + std r0,16(r1) + + /* Save host state to the stack */ + stdu r1, -SWITCH_FRAME_SIZE(r1) + + /* Save r3 (kvm_run) and r4 (vcpu) */ + SAVE_2GPRS(3, r1) + + /* Save non-volatile registers (r14 - r31) */ + SAVE_NVGPRS(r1) + + /* Save LR */ + mflr r14 + std r14, _LINK(r1) + +/* XXX optimize non-volatile loading away */ +kvm_start_lightweight: + + DISABLE_INTERRUPTS + + /* Save R1/R2 in the PACA */ + std r1, PACAR1(r13) + std r2, (PACA_EXMC+EX_SRR0)(r13) + ld r3, VCPU_HIGHMEM_HANDLER(r4) + std r3, PACASAVEDMSR(r13) + + /* Load non-volatile guest state from the vcpu */ + ld r14, VCPU_GPR(r14)(r4) + ld r15, VCPU_GPR(r15)(r4) + ld r16, VCPU_GPR(r16)(r4) + ld r17, VCPU_GPR(r17)(r4) + ld r18, VCPU_GPR(r18)(r4) + ld r19, VCPU_GPR(r19)(r4) + ld r20, VCPU_GPR(r20)(r4) + ld r21, VCPU_GPR(r21)(r4) + ld r22, VCPU_GPR(r22)(r4) + ld r23, VCPU_GPR(r23)(r4) + ld r24, VCPU_GPR(r24)(r4) + ld r25, VCPU_GPR(r25)(r4) + ld r26, VCPU_GPR(r26)(r4) + ld r27, VCPU_GPR(r27)(r4) + ld r28, VCPU_GPR(r28)(r4) + ld r29, VCPU_GPR(r29)(r4) + ld r30, VCPU_GPR(r30)(r4) + ld r31, VCPU_GPR(r31)(r4) + + ld r9, VCPU_PC(r4) /* r9 = vcpu->arch.pc */ + ld r10, VCPU_SHADOW_MSR(r4) /* r10 = vcpu->arch.shadow_msr */ + + ld r3, VCPU_TRAMPOLINE_ENTER(r4) + mtsrr0 r3 + + LOAD_REG_IMMEDIATE(r3, MSR_KERNEL & ~(MSR_IR | MSR_DR)) + mtsrr1 r3 + + /* Load guest state in the respective registers */ + lwz r3, VCPU_CR(r4) /* r3 = vcpu->arch.cr */ + stw r3, (PACA_EXMC + EX_CCR)(r13) + + ld r3, VCPU_CTR(r4) /* r3 = vcpu->arch.ctr */ + mtctr r3 /* CTR = r3 */ + + ld r3, VCPU_LR(r4) /* r3 = vcpu->arch.lr */ + mtlr r3 /* LR = r3 */ + + ld r3, VCPU_XER(r4) /* r3 = vcpu->arch.xer */ + std r3, (PACA_EXMC + EX_R3)(r13) + + /* 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. + */ + + ld r3, VCPU_HFLAGS(r4) + rldicl. r3, r3, 0, 63 /* CR = ((r3 & 1) == 0) */ + beq no_dcbz32_on + + mfspr r3,SPRN_HID5 + ori r3, r3, 0x80 /* XXX HID5_dcbz32 = 0x80 */ + mtspr SPRN_HID5,r3 + +no_dcbz32_on: + /* Load guest GPRs */ + + ld r3, VCPU_GPR(r9)(r4) + std r3, (PACA_EXMC + EX_R9)(r13) + ld r3, VCPU_GPR(r10)(r4) + std r3, (PACA_EXMC + EX_R10)(r13) + ld r3, VCPU_GPR(r11)(r4) + std r3, (PACA_EXMC + EX_R11)(r13) + ld r3, VCPU_GPR(r12)(r4) + std r3, (PACA_EXMC + EX_R12)(r13) + ld r3, VCPU_GPR(r13)(r4) + std r3, (PACA_EXMC + EX_R13)(r13) + + ld r0, VCPU_GPR(r0)(r4) + ld r1, VCPU_GPR(r1)(r4) + ld r2, VCPU_GPR(r2)(r4) + ld r3, VCPU_GPR(r3)(r4) + ld r5, VCPU_GPR(r5)(r4) + ld r6, VCPU_GPR(r6)(r4) + ld r7, VCPU_GPR(r7)(r4) + ld r8, VCPU_GPR(r8)(r4) + ld r4, VCPU_GPR(r4)(r4) + + /* This sets the Magic value for the trampoline */ + + li r11, 1 + stb r11, PACA_KVM_IN_GUEST(r13) + + /* Jump to SLB patching handlder and into our guest */ + RFI + +/* + * This is the handler in module memory. It gets jumped at from the + * lowmem trampoline code, so it's basically the guest exit code. + * + */ + +.global kvmppc_handler_highmem +kvmppc_handler_highmem: + + /* + * Register usage at this point: + * + * R00 = guest R13 + * R01 = host R1 + * R02 = host R2 + * R10 = guest PC + * R11 = guest MSR + * R12 = exit handler id + * R13 = PACA + * PACA.exmc.R9 = guest R1 + * PACA.exmc.R10 = guest R10 + * PACA.exmc.R11 = guest R11 + * PACA.exmc.R12 = guest R12 + * PACA.exmc.R13 = guest R2 + * PACA.exmc.DAR = guest DAR + * PACA.exmc.DSISR = guest DSISR + * PACA.exmc.LR = guest instruction + * PACA.exmc.CCR = guest CR + * PACA.exmc.SRR0 = guest R0 + * + */ + + std r3, (PACA_EXMC+EX_R3)(r13) + + /* save the exit id in R3 */ + mr r3, r12 + + /* R12 = vcpu */ + ld r12, GPR4(r1) + + /* Now save the guest state */ + + std r0, VCPU_GPR(r13)(r12) + std r4, VCPU_GPR(r4)(r12) + std r5, VCPU_GPR(r5)(r12) + std r6, VCPU_GPR(r6)(r12) + std r7, VCPU_GPR(r7)(r12) + std r8, VCPU_GPR(r8)(r12) + std r9, VCPU_GPR(r9)(r12) + + /* get registers from PACA */ + mfpaca r5, r0, EX_SRR0, r12 + mfpaca r5, r3, EX_R3, r12 + mfpaca r5, r1, EX_R9, r12 + mfpaca r5, r10, EX_R10, r12 + mfpaca r5, r11, EX_R11, r12 + mfpaca r5, r12, EX_R12, r12 + mfpaca r5, r2, EX_R13, r12 + + lwz r5, (PACA_EXMC+EX_LR)(r13) + stw r5, VCPU_LAST_INST(r12) + + lwz r5, (PACA_EXMC+EX_CCR)(r13) + stw r5, VCPU_CR(r12) + + ld r5, VCPU_HFLAGS(r12) + rldicl. r5, r5, 0, 63 /* CR = ((r5 & 1) == 0) */ + beq no_dcbz32_off + + mfspr r5,SPRN_HID5 + rldimi r5,r5,6,56 + mtspr SPRN_HID5,r5 + +no_dcbz32_off: + + /* XXX maybe skip on lightweight? */ + std r14, VCPU_GPR(r14)(r12) + std r15, VCPU_GPR(r15)(r12) + std r16, VCPU_GPR(r16)(r12) + std r17, VCPU_GPR(r17)(r12) + std r18, VCPU_GPR(r18)(r12) + std r19, VCPU_GPR(r19)(r12) + std r20, VCPU_GPR(r20)(r12) + std r21, VCPU_GPR(r21)(r12) + std r22, VCPU_GPR(r22)(r12) + std r23, VCPU_GPR(r23)(r12) + std r24, VCPU_GPR(r24)(r12) + std r25, VCPU_GPR(r25)(r12) + std r26, VCPU_GPR(r26)(r12) + std r27, VCPU_GPR(r27)(r12) + std r28, VCPU_GPR(r28)(r12) + std r29, VCPU_GPR(r29)(r12) + std r30, VCPU_GPR(r30)(r12) + std r31, VCPU_GPR(r31)(r12) + + /* Restore non-volatile host registers (r14 - r31) */ + REST_NVGPRS(r1) + + /* Save guest PC (R10) */ + std r10, VCPU_PC(r12) + + /* Save guest msr (R11) */ + std r11, VCPU_SHADOW_MSR(r12) + + /* Save guest CTR (in R12) */ + mfctr r5 + std r5, VCPU_CTR(r12) + + /* Save guest LR */ + mflr r5 + std r5, VCPU_LR(r12) + + /* Save guest XER */ + mfxer r5 + std r5, VCPU_XER(r12) + + /* Save guest DAR */ + ld r5, (PACA_EXMC+EX_DAR)(r13) + std r5, VCPU_FAULT_DEAR(r12) + + /* Save guest DSISR */ + lwz r5, (PACA_EXMC+EX_DSISR)(r13) + std r5, VCPU_FAULT_DSISR(r12) + + /* Restore host msr -> SRR1 */ + ld r7, VCPU_HOST_MSR(r12) + mtsrr1 r7 + + /* Restore host IP -> SRR0 */ + ld r6, VCPU_HOST_RETIP(r12) + mtsrr0 r6 + + /* + * 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. + * + * Call Linux for hardware interrupts/decrementer + * r3 = address of interrupt handler (exit reason) + */ + + cmpwi r3, BOOK3S_INTERRUPT_EXTERNAL + beq call_linux_handler + cmpwi r3, BOOK3S_INTERRUPT_DECREMENTER + beq call_linux_handler + + /* Back to Interruptable Mode! (goto kvm_return_point) */ + RFI + +call_linux_handler: + + /* + * If we land here we need to jump back to the handler we + * came from. + * + * We have a page that we can access from real mode, so let's + * jump back to that and use it as a trampoline to get back into the + * interrupt handler! + * + * R3 still contains the exit code, + * R6 VCPU_HOST_RETIP and + * R7 VCPU_HOST_MSR + */ + + mtlr r3 + + ld r5, VCPU_TRAMPOLINE_LOWMEM(r12) + mtsrr0 r5 + LOAD_REG_IMMEDIATE(r5, MSR_KERNEL & ~(MSR_IR | MSR_DR)) + mtsrr1 r5 + + RFI + +.global kvm_return_point +kvm_return_point: + + /* Jump back to lightweight entry if we're supposed to */ + /* go back into the guest */ + mr r5, r3 + /* Restore r3 (kvm_run) and r4 (vcpu) */ + REST_2GPRS(3, r1) + bl KVMPPC_HANDLE_EXIT + +#if 0 /* XXX get lightweight exits back */ + cmpwi r3, RESUME_GUEST + bne kvm_exit_heavyweight + + /* put VCPU and KVM_RUN back into place and roll again! */ + REST_2GPRS(3, r1) + b kvm_start_lightweight + +kvm_exit_heavyweight: + /* Restore non-volatile host registers */ + ld r14, _LINK(r1) + mtlr r14 + REST_NVGPRS(r1) + + addi r1, r1, SWITCH_FRAME_SIZE +#else + ld r4, _LINK(r1) + mtlr r4 + + cmpwi r3, RESUME_GUEST + bne kvm_exit_heavyweight + + REST_2GPRS(3, r1) + + addi r1, r1, SWITCH_FRAME_SIZE + + b kvm_start_entry + +kvm_exit_heavyweight: + + addi r1, r1, SWITCH_FRAME_SIZE +#endif + + blr |