From: Marc Zyngier <[email protected]> We will soon need to invoke a CPU-specific function pointer after changing page tables, so move post_ttbr_update_workaround out into C code to make this possible.
Signed-off-by: Marc Zyngier <[email protected]> Signed-off-by: Will Deacon <[email protected]> --- arch/arm64/include/asm/assembler.h | 13 ------------- arch/arm64/kernel/entry.S | 2 +- arch/arm64/mm/context.c | 9 +++++++++ arch/arm64/mm/proc.S | 3 +-- 4 files changed, 11 insertions(+), 16 deletions(-) diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index c45bc94f15d0..cee60ce0da52 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -476,17 +476,4 @@ alternative_endif mrs \rd, sp_el0 .endm -/* - * Errata workaround post TTBRx_EL1 update. - */ - .macro post_ttbr_update_workaround -#ifdef CONFIG_CAVIUM_ERRATUM_27456 -alternative_if ARM64_WORKAROUND_CAVIUM_27456 - ic iallu - dsb nsh - isb -alternative_else_nop_endif -#endif - .endm - #endif /* __ASM_ASSEMBLER_H */ diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index 6ceed4877daf..80b539845da6 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -277,7 +277,7 @@ alternative_else_nop_endif * Cavium erratum 27456 (broadcast TLBI instructions may cause I-cache * corruption). */ - post_ttbr_update_workaround + bl post_ttbr_update_workaround .endif 1: .if \el != 0 diff --git a/arch/arm64/mm/context.c b/arch/arm64/mm/context.c index 1cb3bc92ae5c..5f7097d0cd12 100644 --- a/arch/arm64/mm/context.c +++ b/arch/arm64/mm/context.c @@ -239,6 +239,15 @@ void check_and_switch_context(struct mm_struct *mm, unsigned int cpu) cpu_switch_mm(mm->pgd, mm); } +/* Errata workaround post TTBRx_EL1 update. */ +asmlinkage void post_ttbr_update_workaround(void) +{ + asm(ALTERNATIVE("nop; nop; nop", + "ic iallu; dsb nsh; isb", + ARM64_WORKAROUND_CAVIUM_27456, + CONFIG_CAVIUM_ERRATUM_27456)); +} + static int asids_init(void) { asid_bits = get_cpu_asid_bits(); diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index 3146dc96f05b..6affb68a9a14 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -145,8 +145,7 @@ ENTRY(cpu_do_switch_mm) isb msr ttbr0_el1, x0 // now update TTBR0 isb - post_ttbr_update_workaround - ret + b post_ttbr_update_workaround // Back to C code... ENDPROC(cpu_do_switch_mm) .pushsection ".idmap.text", "ax" -- 2.1.4
