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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 handle_dar_dsisr=0
EXCEPTION_PROLOG_0 handle_dar_dsisr=\handle_dar_dsisr
EXCEPTION_PROLOG_1
EXCEPTION_PROLOG_2 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
#ifdef CONFIG_VMAP_STACK
mfspr r10, SPRN_SPRG_THREAD
.if \handle_dar_dsisr
mfspr r11, SPRN_DAR
stw r11, DAR(r10)
mfspr r11, SPRN_DSISR
stw r11, DSISR(r10)
.endif
mfspr r11, SPRN_SRR0
stw r11, SRR0(r10)
#endif
mfspr r11, SPRN_SRR1 /* check whether user or kernel */
#ifdef CONFIG_VMAP_STACK
stw r11, SRR1(r10)
#endif
mfcr r10
andi. r11, r11, MSR_PR
.endm
.macro EXCEPTION_PROLOG_1 for_rtas=0
#ifdef CONFIG_VMAP_STACK
.ifeq \for_rtas
li r11, MSR_KERNEL & ~(MSR_IR | MSR_RI) /* can take DTLB miss */
mtmsr r11
isync
.endif
subi r11, r1, INT_FRAME_SIZE /* use r1 if kernel */
#else
tophys(r11,r1) /* use tophys(r1) if kernel */
subi r11, r11, INT_FRAME_SIZE /* alloc exc. frame */
#endif
beq 1f
mfspr r11,SPRN_SPRG_THREAD
tovirt_vmstack r11, r11
lwz r11,TASK_STACK-THREAD(r11)
addi r11, r11, THREAD_SIZE - INT_FRAME_SIZE
tophys_novmstack r11, r11
1:
#ifdef CONFIG_VMAP_STACK
mtcrf 0x7f, r11
bt 32 - THREAD_ALIGN_SHIFT, stack_overflow
#endif
.endm
.macro EXCEPTION_PROLOG_2 handle_dar_dsisr=0
stw r10,_CCR(r11) /* save registers */
stw r12,GPR12(r11)
stw r9,GPR9(r11)
mfspr r10,SPRN_SPRG_SCRATCH0
stw r10,GPR10(r11)
mfspr r12,SPRN_SPRG_SCRATCH1
stw r12,GPR11(r11)
mflr r10
stw r10,_LINK(r11)
#ifdef CONFIG_VMAP_STACK
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)
#else
mfspr r12,SPRN_SRR0
mfspr r9,SPRN_SRR1
#endif
stw r1,GPR1(r11)
stw r1,0(r11)
tovirt_novmstack r1, r11 /* set new kernel sp */
#ifdef CONFIG_40x
rlwinm r9,r9,0,14,12 /* clear MSR_WE (necessary?) */
#else
#ifdef CONFIG_VMAP_STACK
li r10, MSR_KERNEL & ~MSR_IR /* can take exceptions */
#else
li r10,MSR_KERNEL & ~(MSR_IR|MSR_DR) /* can take exceptions */
#endif
mtmsr r10 /* (except for mach check in rtas) */
#endif
stw r0,GPR0(r11)
lis r10,STACK_FRAME_REGS_MARKER@ha /* exception frame marker */
addi r10,r10,STACK_FRAME_REGS_MARKER@l
stw r10,8(r11)
SAVE_4GPRS(3, r11)
SAVE_2GPRS(7, r11)
.endm
.macro SYSCALL_ENTRY trapno
mfspr r12,SPRN_SPRG_THREAD
#ifdef CONFIG_VMAP_STACK
mfspr r9, SPRN_SRR0
mfspr r11, SPRN_SRR1
stw r9, SRR0(r12)
stw r11, SRR1(r12)
#endif
mfcr r10
lwz r11,TASK_STACK-THREAD(r12)
rlwinm r10,r10,0,4,2 /* Clear SO bit in CR */
addi r11, r11, THREAD_SIZE - INT_FRAME_SIZE
#ifdef CONFIG_VMAP_STACK
li r9, MSR_KERNEL & ~(MSR_IR | MSR_RI) /* can take DTLB miss */
mtmsr r9
isync
#endif
tovirt_vmstack r12, r12
tophys_novmstack r11, r11
mflr r9
stw r10,_CCR(r11) /* save registers */
stw r9, _LINK(r11)
#ifdef CONFIG_VMAP_STACK
lwz r10, SRR0(r12)
lwz r9, SRR1(r12)
#else
mfspr r10,SPRN_SRR0
mfspr r9,SPRN_SRR1
#endif
stw r1,GPR1(r11)
stw r1,0(r11)
tovirt_novmstack r1, r11 /* set new kernel sp */
stw r10,_NIP(r11)
#ifdef CONFIG_40x
rlwinm r9,r9,0,14,12 /* clear MSR_WE (necessary?) */
#else
#ifdef CONFIG_VMAP_STACK
LOAD_REG_IMMEDIATE(r10, MSR_KERNEL & ~MSR_IR) /* can take exceptions */
#else
LOAD_REG_IMMEDIATE(r10, MSR_KERNEL & ~(MSR_IR|MSR_DR)) /* can take exceptions */
#endif
mtmsr r10 /* (except for mach check in rtas) */
#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 + 1
stw r10,8(r11)
stw r2,_TRAP(r11)
SAVE_GPR(0, r11)
SAVE_4GPRS(3, r11)
SAVE_2GPRS(7, r11)
addi r11,r1,STACK_FRAME_OVERHEAD
addi r2,r12,-THREAD
stw r11,PT_REGS(r12)
#if defined(CONFIG_40x)
/* Check to see if the dbcr0 register is set up to debug. Use the
internal debug mode bit to do this. */
lwz r12,THREAD_DBCR0(r12)
andis. r12,r12,DBCR0_IDM@h
#endif
ACCOUNT_CPU_USER_ENTRY(r2, r11, r12)
#if defined(CONFIG_40x)
beq+ 3f
/* From user and task is ptraced - load up global dbcr0 */
li r12,-1 /* clear all pending debug events */
mtspr SPRN_DBSR,r12
lis r11,global_dbcr0@ha
tophys(r11,r11)
addi r11,r11,global_dbcr0@l
lwz r12,0(r11)
mtspr SPRN_DBCR0,r12
lwz r12,4(r11)
addi r12,r12,-1
stw r12,4(r11)
#endif
3:
tovirt_novmstack r2, r2 /* set r2 to current */
lis r11, transfer_to_syscall@h
ori r11, r11, transfer_to_syscall@l
#ifdef CONFIG_TRACE_IRQFLAGS
/*
* If MSR is changing we need to keep interrupts disabled at this point
* otherwise we might risk taking an interrupt before we tell lockdep
* they are enabled.
*/
LOAD_REG_IMMEDIATE(r10, MSR_KERNEL)
rlwimi r10, r9, 0, MSR_EE
#else
LOAD_REG_IMMEDIATE(r10, MSR_KERNEL | MSR_EE)
#endif
#if defined(CONFIG_PPC_8xx) && defined(CONFIG_PERF_EVENTS)
mtspr SPRN_NRI, r0
#endif
mtspr SPRN_SRR1,r10
mtspr SPRN_SRR0,r11
SYNC
RFI /* jump to handler, enable MMU */
.endm
.macro save_dar_dsisr_on_stack reg1, reg2, sp
#ifndef CONFIG_VMAP_STACK
mfspr \reg1, SPRN_DAR
mfspr \reg2, SPRN_DSISR
stw \reg1, _DAR(\sp)
stw \reg2, _DSISR(\sp)
#endif
.endm
.macro get_and_save_dar_dsisr_on_stack reg1, reg2, sp
#ifdef CONFIG_VMAP_STACK
lwz \reg1, _DAR(\sp)
lwz \reg2, _DSISR(\sp)
#else
save_dar_dsisr_on_stack \reg1, \reg2, \sp
#endif
.endm
.macro tovirt_vmstack dst, src
#ifdef CONFIG_VMAP_STACK
tovirt(\dst, \src)
#else
.ifnc \dst, \src
mr \dst, \src
.endif
#endif
.endm
.macro tovirt_novmstack dst, src
#ifndef CONFIG_VMAP_STACK
tovirt(\dst, \src)
#else
.ifnc \dst, \src
mr \dst, \src
.endif
#endif
.endm
.macro tophys_novmstack dst, src
#ifndef CONFIG_VMAP_STACK
tophys(\dst, \src)
#else
.ifnc \dst, \src
mr \dst, \src
.endif
#endif
.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) \
. = n; \
DO_KVM n; \
label:
#else
#define START_EXCEPTION(n, label) \
. = n; \
label:
#endif
#define EXCEPTION(n, label, hdlr, xfer) \
START_EXCEPTION(n, label) \
EXCEPTION_PROLOG; \
addi r3,r1,STACK_FRAME_OVERHEAD; \
xfer(n, hdlr)
#define EXC_XFER_TEMPLATE(hdlr, trap, msr, tfer, ret) \
li r10,trap; \
stw r10,_TRAP(r11); \
LOAD_REG_IMMEDIATE(r10, msr); \
bl tfer; \
.long hdlr; \
.long ret
#define EXC_XFER_STD(n, hdlr) \
EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, transfer_to_handler_full, \
ret_from_except_full)
#define EXC_XFER_LITE(n, hdlr) \
EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, transfer_to_handler, \
ret_from_except)
.macro vmap_stack_overflow_exception
#ifdef CONFIG_VMAP_STACK
#ifdef CONFIG_SMP
mfspr r11, SPRN_SPRG_THREAD
tovirt(r11, r11)
lwz r11, TASK_CPU - THREAD(r11)
slwi r11, r11, 3
addis r11, r11, emergency_ctx@ha
#else
lis r11, emergency_ctx@ha
#endif
lwz r11, emergency_ctx@l(r11)
cmpwi cr1, r11, 0
bne cr1, 1f
lis r11, init_thread_union@ha
addi r11, r11, init_thread_union@l
1: addi r11, r11, THREAD_SIZE - INT_FRAME_SIZE
EXCEPTION_PROLOG_2
SAVE_NVGPRS(r11)
addi r3, r1, STACK_FRAME_OVERHEAD
EXC_XFER_STD(0, stack_overflow_exception)
#endif
.endm
#endif /* __HEAD_32_H__ */
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