Commit a3055978 authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/32: Refactor saving of volatile registers in exception prologs 



Exception prologs all do the same at the end:
- Save trapno in stack
- Mark stack with exception marker
- Save r0
- Save r3 to r8

Refactor that into a COMMON_EXCEPTION_PROLOG_END macro.
At the same time use r1 instead of r11.

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/e1c45d2e895e0693c42d2a6840df1105a148efea.1615552867.git.christophe.leroy@csgroup.eu
parent acc142b6

arch/powerpc/kernel/head_32.h

+10 −6
Original line number Diff line number Diff line
@@ -104,15 +104,19 @@ 
	li	r10, MSR_KERNEL		/* can take exceptions */

	mtmsr	r10			/* (except for mach check in rtas) */

#endif

	stw	r0,GPR0(r11)

	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(r11)

	stw	r10,8(r1)

	li	r10, \trapno

	stw	r10,_TRAP(r11)

	SAVE_4GPRS(3, r11)

	SAVE_2GPRS(7, r11)

_ASM_NOKPROBE_SYMBOL(\name\()_virt)

	stw	r10,_TRAP(r1)

	SAVE_4GPRS(3, r1)

	SAVE_2GPRS(7, r1)

.endm



.macro prepare_transfer_to_handler

arch/powerpc/kernel/head_40x.S

+1 −8
Original line number Diff line number Diff line
@@ -157,14 +157,7 @@ _ENTRY(crit_esr) 
	mfspr	r12,SPRN_SRR2

	mfspr	r9,SPRN_SRR3

	rlwinm	r9,r9,0,14,12		/* clear MSR_WE (necessary?)	   */

	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)

	li	r10, \trapno + 2

	stw	r10,_TRAP(r11)

	SAVE_4GPRS(3, r11)

	SAVE_2GPRS(7, r11)

	COMMON_EXCEPTION_PROLOG_END \trapno + 2

_ASM_NOKPROBE_SYMBOL(\name\()_virt)

.endm

arch/powerpc/kernel/head_booke.h

+13 −13
Original line number Diff line number Diff line
@@ -78,14 +78,18 @@ END_BTB_FLUSH_SECTION 
	stw	r1, 0(r11);						     \

	mr	r1, r11;						     \

	rlwinm	r9,r9,0,14,12;		/* clear MSR_WE (necessary?)	   */\

	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);						     \

	li	r10, trapno;						     \

	stw	r10,_TRAP(r11);						     \

	SAVE_4GPRS(3, r11);						     \

	SAVE_2GPRS(7, r11)

	COMMON_EXCEPTION_PROLOG_END trapno



.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)

.endm



.macro prepare_transfer_to_handler

	bl	prepare_transfer_to_handler
@@ -231,11 +235,7 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV) 
	stw	r1,0(r11);						     \

	mr	r1,r11;							     \

	rlwinm	r9,r9,0,14,12;		/* clear MSR_WE (necessary?)	   */\

	li	r10, trapno;						     \

	stw	r10,_TRAP(r11);						     \

	stw	r0,GPR0(r11);						     \

	SAVE_4GPRS(3, r11);						     \

	SAVE_2GPRS(7, r11)

	COMMON_EXCEPTION_PROLOG_END trapno



#define SAVE_xSRR(xSRR)			\

	mfspr	r0,SPRN_##xSRR##0;	\