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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __HEAD_32_H__
#define __HEAD_32_H__
#include <asm/ptrace.h> /* for STACK_FRAME_REGS_MARKER */
/*
* Exception entry code. This code runs with address translation
* turned off, i.e. using physical addresses.
* We assume sprg3 has the physical address of the current
* task's thread_struct.
*/
.macro EXCEPTION_PROLOG trapno name handle_dar_dsisr=0
EXCEPTION_PROLOG_0 handle_dar_dsisr=\handle_dar_dsisr
EXCEPTION_PROLOG_1
EXCEPTION_PROLOG_2 \trapno \name handle_dar_dsisr=\handle_dar_dsisr
.endm
.macro EXCEPTION_PROLOG_0 handle_dar_dsisr=0
mtspr SPRN_SPRG_SCRATCH0,r10
mtspr SPRN_SPRG_SCRATCH1,r11
mfspr r10, SPRN_SPRG_THREAD
.if \handle_dar_dsisr
#ifdef CONFIG_40x
mfspr r11, SPRN_DEAR
#else
mfspr r11, SPRN_DAR
#endif
stw r11, DAR(r10)
#ifdef CONFIG_40x
mfspr r11, SPRN_ESR
#else
mfspr r11, SPRN_DSISR
#endif
stw r11, DSISR(r10)
.endif
mfspr r11, SPRN_SRR0
stw r11, SRR0(r10)
mfspr r11, SPRN_SRR1 /* check whether user or kernel */
stw r11, SRR1(r10)
mfcr r10
andi. r11, r11, MSR_PR
.endm
.macro EXCEPTION_PROLOG_1
mtspr SPRN_SPRG_SCRATCH2,r1
subi r1, r1, INT_FRAME_SIZE /* use r1 if kernel */
beq 1f
mfspr r1,SPRN_SPRG_THREAD
lwz r1,TASK_STACK-THREAD(r1)
addi r1, r1, THREAD_SIZE - INT_FRAME_SIZE
1:
#ifdef CONFIG_VMAP_STACK
mtcrf 0x3f, r1
bt 32 - THREAD_ALIGN_SHIFT, vmap_stack_overflow
#endif
.endm
.macro EXCEPTION_PROLOG_2 trapno name handle_dar_dsisr=0
#ifdef CONFIG_PPC_8xx
.if \handle_dar_dsisr
li r11, RPN_PATTERN
mtspr SPRN_DAR, r11 /* Tag DAR, to be used in DTLB Error */
.endif
#endif
LOAD_REG_IMMEDIATE(r11, MSR_KERNEL & ~MSR_RI) /* re-enable MMU */
mtspr SPRN_SRR1, r11
lis r11, 1f@h
ori r11, r11, 1f@l
mtspr SPRN_SRR0, r11
mfspr r11, SPRN_SPRG_SCRATCH2
rfi
.text
\name\()_virt:
1:
stw r11,GPR1(r1)
stw r11,0(r1)
mr r11, r1
stw r10,_CCR(r11) /* save registers */
stw r12,GPR12(r11)
stw r9,GPR9(r11)
mfspr r10,SPRN_SPRG_SCRATCH0
mfspr r12,SPRN_SPRG_SCRATCH1
stw r10,GPR10(r11)
stw r12,GPR11(r11)
mflr r10
stw r10,_LINK(r11)
mfspr r12, SPRN_SPRG_THREAD
tovirt(r12, r12)
.if \handle_dar_dsisr
lwz r10, DAR(r12)
stw r10, _DAR(r11)
lwz r10, DSISR(r12)
stw r10, _DSISR(r11)
.endif
lwz r9, SRR1(r12)
lwz r12, SRR0(r12)
#ifdef CONFIG_40x
rlwinm r9,r9,0,14,12 /* clear MSR_WE (necessary?) */
#elif defined(CONFIG_PPC_8xx)
mtspr SPRN_EID, r2 /* Set MSR_RI */
#else
li r10, MSR_KERNEL /* can take exceptions */
mtmsr r10 /* (except for mach check in rtas) */
#endif
COMMON_EXCEPTION_PROLOG_END \trapno
_ASM_NOKPROBE_SYMBOL(\name\()_virt)
.endm
.macro COMMON_EXCEPTION_PROLOG_END trapno
stw r0,GPR0(r1)
lis r10,STACK_FRAME_REGS_MARKER@ha /* exception frame marker */
addi r10,r10,STACK_FRAME_REGS_MARKER@l
stw r10,8(r1)
li r10, \trapno
stw r10,_TRAP(r1)
SAVE_4GPRS(3, r1)
SAVE_2GPRS(7, r1)
SAVE_NVGPRS(r1)
stw r2,GPR2(r1)
stw r12,_NIP(r1)
stw r9,_MSR(r1)
mfctr r10
mfspr r2,SPRN_SPRG_THREAD
stw r10,_CTR(r1)
tovirt(r2, r2)
mfspr r10,SPRN_XER
addi r2, r2, -THREAD
stw r10,_XER(r1)
addi r3,r1,STACK_FRAME_OVERHEAD
.endm
.macro prepare_transfer_to_handler
#ifdef CONFIG_PPC_BOOK3S_32
andi. r12,r9,MSR_PR
bne 777f
bl prepare_transfer_to_handler
777:
#endif
.endm
.macro SYSCALL_ENTRY trapno
mfspr r9, SPRN_SRR1
mfspr r10, SPRN_SRR0
LOAD_REG_IMMEDIATE(r11, MSR_KERNEL) /* can take exceptions */
lis r12, 1f@h
ori r12, r12, 1f@l
mtspr SPRN_SRR1, r11
mtspr SPRN_SRR0, r12
mfspr r12,SPRN_SPRG_THREAD
mr r11, r1
lwz r1,TASK_STACK-THREAD(r12)
tovirt(r12, r12)
addi r1, r1, THREAD_SIZE - INT_FRAME_SIZE
rfi
1:
stw r11,GPR1(r1)
stw r11,0(r1)
mr r11, r1
stw r10,_NIP(r11)
mflr r10
stw r10, _LINK(r11)
mfcr r10
rlwinm r10,r10,0,4,2 /* Clear SO bit in CR */
stw r10,_CCR(r11) /* save registers */
#ifdef CONFIG_40x
rlwinm r9,r9,0,14,12 /* clear MSR_WE (necessary?) */
#endif
lis r10,STACK_FRAME_REGS_MARKER@ha /* exception frame marker */
stw r2,GPR2(r11)
addi r10,r10,STACK_FRAME_REGS_MARKER@l
stw r9,_MSR(r11)
li r2, \trapno
stw r10,8(r11)
stw r2,_TRAP(r11)
SAVE_GPR(0, r11)
SAVE_4GPRS(3, r11)
SAVE_2GPRS(7, r11)
addi r2,r12,-THREAD
b transfer_to_syscall /* jump to handler */
.endm
/*
* Note: code which follows this uses cr0.eq (set if from kernel),
* r11, r12 (SRR0), and r9 (SRR1).
*
* Note2: once we have set r1 we are in a position to take exceptions
* again, and we could thus set MSR:RI at that point.
*/
/*
* Exception vectors.
*/
#ifdef CONFIG_PPC_BOOK3S
#define START_EXCEPTION(n, label) \
__HEAD; \
. = n; \
DO_KVM n; \
label:
#else
#define START_EXCEPTION(n, label) \
__HEAD; \
. = n; \
label:
#endif
#define EXCEPTION(n, label, hdlr) \
START_EXCEPTION(n, label) \
EXCEPTION_PROLOG n label; \
prepare_transfer_to_handler; \
bl hdlr; \
b interrupt_return
.macro vmap_stack_overflow_exception
__HEAD
vmap_stack_overflow:
#ifdef CONFIG_SMP
mfspr r1, SPRN_SPRG_THREAD
lwz r1, TASK_CPU - THREAD(r1)
slwi r1, r1, 3
addis r1, r1, emergency_ctx@ha
#else
lis r1, emergency_ctx@ha
#endif
lwz r1, emergency_ctx@l(r1)
addi r1, r1, THREAD_SIZE - INT_FRAME_SIZE
EXCEPTION_PROLOG_2 0 vmap_stack_overflow
prepare_transfer_to_handler
bl stack_overflow_exception
b interrupt_return
.endm
#endif /* __HEAD_32_H__ */
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