From 62182e6c0faf75117f8d1719c118bb5fc8574012 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Sun, 8 Nov 2020 16:57:37 +0000 Subject: 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: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/f7e9cb9e9240feec63cb330abf40b67d1aad852f.1604854583.git.christophe.leroy@csgroup.eu --- arch/powerpc/kernel/entry_32.S | 30 ++++++++++++++++++++++++------ arch/powerpc/kernel/head_32.h | 5 ++++- 2 files changed, 28 insertions(+), 7 deletions(-) (limited to 'arch/powerpc/kernel') diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S index e10e1167ffb1..c7c28e8acc10 100644 --- a/arch/powerpc/kernel/entry_32.S +++ b/arch/powerpc/kernel/entry_32.S @@ -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)) diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h index 7c767765071d..232000742c9a 100644 --- a/arch/powerpc/kernel/head_32.h +++ b/arch/powerpc/kernel/head_32.h @@ -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 -- cgit v1.2.3