linux-stable-rt/arch/powerpc/kvm/book3s_rmhandlers.S

257 lines
6.2 KiB
ArmAsm

/*
* 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) GET_PACA(reg)
#define MSR_NOIRQ MSR_KERNEL & ~(MSR_IR | MSR_DR)
#define FUNC(name) GLUE(.,name)
kvmppc_skip_interrupt:
/*
* Here all GPRs are unchanged from when the interrupt happened
* except for r13, which is saved in SPRG_SCRATCH0.
*/
mfspr r13, SPRN_SRR0
addi r13, r13, 4
mtspr SPRN_SRR0, r13
GET_SCRATCH0(r13)
rfid
b .
kvmppc_skip_Hinterrupt:
/*
* Here all GPRs are unchanged from when the interrupt happened
* except for r13, which is saved in SPRG_SCRATCH0.
*/
mfspr r13, SPRN_HSRR0
addi r13, r13, 4
mtspr SPRN_HSRR0, r13
GET_SCRATCH0(r13)
hrfid
b .
#elif defined(CONFIG_PPC_BOOK3S_32)
#define MSR_NOIRQ MSR_KERNEL
#define FUNC(name) name
.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 */
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
#endif
/*
* 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
/* load_up_xxx have to run with MSR_DR=0 on Book3S_32 */
#define MSR_EXT_START \
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
#define MSR_EXT_END \
mtmsr r20; /* Enable DR,EE */ \
sync; \
PPC_LL r20, _NIP(r1)
#elif defined(CONFIG_PPC_BOOK3S_64)
#define STACK_LR _LINK
#define MSR_EXT_START
#define MSR_EXT_END
#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); \
MSR_EXT_START; \
\
bl FUNC(load_up_ ## what); \
\
MSR_EXT_END; \
PPC_LL r3, STACK_LR(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
#include "book3s_segment.S"