diff options
author | Samuel Holland <samuel.holland@sifive.com> | 2024-03-26 21:49:49 -0700 |
---|---|---|
committer | Palmer Dabbelt <palmer@rivosinc.com> | 2024-04-29 10:49:31 -0700 |
commit | d6dcdabafcd7c612b164079d00da6d9775863a0b (patch) | |
tree | 891257d2841136d48575cc49123a13f10974beb3 /arch/riscv/include | |
parent | 20e03d702e00a3e0269a1d6f9549c2e370492054 (diff) |
riscv: Avoid TLB flush loops when affected by SiFive CIP-1200
Implementations affected by SiFive errata CIP-1200 have a bug which
forces the kernel to always use the global variant of the sfence.vma
instruction. When affected by this errata, do not attempt to flush a
range of addresses; each iteration of the loop would actually flush the
whole TLB instead. Instead, minimize the overall number of sfence.vma
instructions.
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Yunhui Cui <cuiyunhui@bytedance.com>
Link: https://lore.kernel.org/r/20240327045035.368512-9-samuel.holland@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Diffstat (limited to 'arch/riscv/include')
-rw-r--r-- | arch/riscv/include/asm/tlbflush.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/riscv/include/asm/tlbflush.h b/arch/riscv/include/asm/tlbflush.h index 463b615d7728..8e329721375b 100644 --- a/arch/riscv/include/asm/tlbflush.h +++ b/arch/riscv/include/asm/tlbflush.h @@ -66,6 +66,8 @@ void arch_tlbbatch_add_pending(struct arch_tlbflush_unmap_batch *batch, unsigned long uaddr); void arch_flush_tlb_batched_pending(struct mm_struct *mm); void arch_tlbbatch_flush(struct arch_tlbflush_unmap_batch *batch); + +extern unsigned long tlb_flush_all_threshold; #else /* CONFIG_MMU */ #define local_flush_tlb_all() do { } while (0) #endif /* CONFIG_MMU */ |