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| author | Mayuresh Chitale <mchitale@ventanamicro.com> | 2024-07-02 15:56:37 +0530 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@dabbelt.com> | 2025-06-05 14:03:06 -0700 |
| commit | a56972698810089d8f1bdc296cd709726db7176b (patch) | |
| tree | 63d4e66994bba4f1c6d409baf12d011cc3dd8461 | |
| parent | 82f2b0b97b36ee3fcddf0f0780a9a0825d52fec3 (diff) | |
| download | linux-a56972698810089d8f1bdc296cd709726db7176b.tar.gz | |
riscv: mm: Add support for Svinval extension
The Svinval extension splits SFENCE.VMA instruction into finer-grained
invalidation and ordering operations and is mandatory for RVA23S64 profile.
When Svinval is enabled the local_flush_tlb_range_threshold_asid function
should use the following sequence to optimize the tlb flushes instead of
a simple sfence.vma:
sfence.w.inval
svinval.vma
.
.
svinval.vma
sfence.inval.ir
The maximum number of consecutive svinval.vma instructions that
can be executed in local_flush_tlb_range_threshold_asid function
is limited to 64. This is required to avoid soft lockups and the
approach is similar to that used in arm64.
Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20240702102637.9074-1-mchitale@ventanamicro.com
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
| -rw-r--r-- | arch/riscv/mm/tlbflush.c | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/arch/riscv/mm/tlbflush.c b/arch/riscv/mm/tlbflush.c index f9e27ba1df99ff..6289ed5c7eb457 100644 --- a/arch/riscv/mm/tlbflush.c +++ b/arch/riscv/mm/tlbflush.c @@ -7,6 +7,27 @@ #include <linux/mmu_notifier.h> #include <asm/sbi.h> #include <asm/mmu_context.h> +#include <asm/cpufeature.h> + +#define has_svinval() riscv_has_extension_unlikely(RISCV_ISA_EXT_SVINVAL) + +static inline void local_sfence_inval_ir(void) +{ + asm volatile(SFENCE_INVAL_IR() ::: "memory"); +} + +static inline void local_sfence_w_inval(void) +{ + asm volatile(SFENCE_W_INVAL() ::: "memory"); +} + +static inline void local_sinval_vma(unsigned long vma, unsigned long asid) +{ + if (asid != FLUSH_TLB_NO_ASID) + asm volatile(SINVAL_VMA(%0, %1) : : "r" (vma), "r" (asid) : "memory"); + else + asm volatile(SINVAL_VMA(%0, zero) : : "r" (vma) : "memory"); +} /* * Flush entire TLB if number of entries to be flushed is greater @@ -27,6 +48,16 @@ static void local_flush_tlb_range_threshold_asid(unsigned long start, return; } + if (has_svinval()) { + local_sfence_w_inval(); + for (i = 0; i < nr_ptes_in_range; ++i) { + local_sinval_vma(start, asid); + start += stride; + } + local_sfence_inval_ir(); + return; + } + for (i = 0; i < nr_ptes_in_range; ++i) { local_flush_tlb_page_asid(start, asid); start += stride; |