Commit 62182e6c authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc: Remove RFI macro 



RFI macro is just there to add an infinite loop past
rfi in order to avoid prefetch on 40x in half a dozen
of places in entry_32 and head_32.

Those places are already full of #ifdefs, so just add a
few more to explicitely show those loops and remove RFI.

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/f7e9cb9e9240feec63cb330abf40b67d1aad852f.1604854583.git.christophe.leroy@csgroup.eu
parent 120c0518

arch/powerpc/include/asm/ppc_asm.h

+0 −5
Original line number Diff line number Diff line
@@ -498,11 +498,6 @@ END_FTR_SECTION_NESTED(CPU_FTR_CELL_TB_BUG, CPU_FTR_CELL_TB_BUG, 96) 
#define MTMSRD(r)	mtmsrd	r

#define MTMSR_EERI(reg)	mtmsrd	reg,1

#else

#ifndef CONFIG_40x

#define	RFI		rfi

#else

#define RFI		rfi; b .	/* Prevent prefetch past rfi */

#endif

#define MTMSRD(r)	mtmsr	r

#define MTMSR_EERI(reg)	mtmsr	reg

#endif

arch/powerpc/kernel/entry_32.S

+24 −6
Original line number Diff line number Diff line
@@ -234,7 +234,10 @@ transfer_to_handler_cont: 
	mtspr	SPRN_SRR0,r11

	mtspr	SPRN_SRR1,r10

	mtlr	r9

	RFI				/* jump to handler, enable MMU */

	rfi				/* jump to handler, enable MMU */

#ifdef CONFIG_40x

	b .	/* Prevent prefetch past rfi */

#endif



#if defined (CONFIG_PPC_BOOK3S_32) || defined(CONFIG_E500)

4:	rlwinm	r12,r12,0,~_TLF_NAPPING
@@ -263,7 +266,10 @@ _ASM_NOKPROBE_SYMBOL(transfer_to_handler_cont) 
	LOAD_REG_IMMEDIATE(r0, MSR_KERNEL)

	mtspr	SPRN_SRR0,r12

	mtspr	SPRN_SRR1,r0

	RFI

	rfi

#ifdef CONFIG_40x

	b .	/* Prevent prefetch past rfi */

#endif



reenable_mmu:

	/*
@@ -321,7 +327,10 @@ stack_ovf: 
#endif

	mtspr	SPRN_SRR0,r9

	mtspr	SPRN_SRR1,r10

	RFI

	rfi

#ifdef CONFIG_40x

	b .	/* Prevent prefetch past rfi */

#endif

_ASM_NOKPROBE_SYMBOL(stack_ovf)

#endif
@@ -470,7 +479,10 @@ syscall_exit_finish: 
#endif

	mtspr	SPRN_SRR0,r7

	mtspr	SPRN_SRR1,r8

	RFI

	rfi

#ifdef CONFIG_40x

	b .	/* Prevent prefetch past rfi */

#endif

_ASM_NOKPROBE_SYMBOL(syscall_exit_finish)

#ifdef CONFIG_44x

2:	li	r7,0
@@ -600,7 +612,10 @@ ret_from_kernel_syscall: 
#endif

	mtspr	SPRN_SRR0, r9

	mtspr	SPRN_SRR1, r10

	RFI

	rfi

#ifdef CONFIG_40x

	b .	/* Prevent prefetch past rfi */

#endif

_ASM_NOKPROBE_SYMBOL(ret_from_kernel_syscall)



/*
@@ -803,7 +818,10 @@ fast_exception_return: 
	REST_GPR(9, r11)

	REST_GPR(12, r11)

	lwz	r11,GPR11(r11)

	RFI

	rfi

#ifdef CONFIG_40x

	b .	/* Prevent prefetch past rfi */

#endif

_ASM_NOKPROBE_SYMBOL(fast_exception_return)



#if !(defined(CONFIG_4xx) || defined(CONFIG_BOOKE))

arch/powerpc/kernel/head_32.h

+4 −1
Original line number Diff line number Diff line
@@ -222,7 +222,10 @@ 
#endif

	mtspr	SPRN_SRR1,r10

	mtspr	SPRN_SRR0,r11

	RFI				/* jump to handler, enable MMU */

	rfi				/* jump to handler, enable MMU */

#ifdef CONFIG_40x

	b .	/* Prevent prefetch past rfi */

#endif

99:	b	ret_from_kernel_syscall

.endm