forked from Minki/linux
d5e528136c
Linux contains quite some bits of code to load FPU, Altivec and VSX lazily for a task. It calls those bits in real mode, coming from an interrupt handler. For KVM we better reuse those, so let's wrap a bit of trampoline magic around them and then we can call them from normal module code. Signed-off-by: Alexander Graf <agraf@suse.de> Signed-off-by: Avi Kivity <avi@redhat.com>
205 lines
5.2 KiB
ArmAsm
205 lines
5.2 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>
|
|
#include <asm/exception-64s.h>
|
|
|
|
/*****************************************************************************
|
|
* *
|
|
* Real Mode handlers that need to be in low physical memory *
|
|
* *
|
|
****************************************************************************/
|
|
|
|
|
|
.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
|
|
*/
|
|
mfspr r13, SPRN_SPRG_PACA /* r13 = PACA */
|
|
std r12, PACA_KVM_SCRATCH0(r13)
|
|
mfcr r12
|
|
stw r12, PACA_KVM_SCRATCH1(r13)
|
|
lbz r12, PACA_KVM_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, PACA_KVM_SCRATCH1(r13)
|
|
mtcr r12
|
|
ld r12, PACA_KVM_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_DATA_SEGMENT
|
|
INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_INST_STORAGE
|
|
INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_INST_SEGMENT
|
|
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
|
|
INTERRUPT_TRAMPOLINE BOOK3S_INTERRUPT_VSX
|
|
|
|
/*
|
|
* 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 = PACA
|
|
* PACA.KVM.SCRATCH0 = guest R12
|
|
* PACA.KVM.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, PACA_KVM_SCRATCH1(r13)
|
|
mtcr r12
|
|
ld r12, PACA_KVM_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 = CTR
|
|
*
|
|
*/
|
|
_GLOBAL(kvmppc_rmcall)
|
|
mtmsr r4 /* Disable relocation, so mtsrr
|
|
doesn't get interrupted */
|
|
mtctr r5
|
|
mtsrr0 r3
|
|
mtsrr1 r4
|
|
RFI
|
|
|
|
/*
|
|
* Activate current's external feature (FPU/Altivec/VSX)
|
|
*/
|
|
#define define_load_up(what) \
|
|
\
|
|
_GLOBAL(kvmppc_load_up_ ## what); \
|
|
subi r1, r1, INT_FRAME_SIZE; \
|
|
mflr r3; \
|
|
std r3, _LINK(r1); \
|
|
mfmsr r4; \
|
|
std r31, GPR3(r1); \
|
|
mr r31, r4; \
|
|
li r5, MSR_DR; \
|
|
oris r5, r5, MSR_EE@h; \
|
|
andc r4, r4, r5; \
|
|
mtmsr r4; \
|
|
\
|
|
bl .load_up_ ## what; \
|
|
\
|
|
mtmsr r31; \
|
|
ld r3, _LINK(r1); \
|
|
ld r31, GPR3(r1); \
|
|
addi r1, r1, INT_FRAME_SIZE; \
|
|
mtlr r3; \
|
|
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 - _stext
|
|
|
|
.global kvmppc_trampoline_enter
|
|
kvmppc_trampoline_enter:
|
|
.long kvmppc_handler_trampoline_enter - _stext
|
|
|
|
#include "book3s_64_slb.S"
|
|
|