This is a note to let you know that I've just added the patch titled
riscv: Apply SiFive CIP-1200 workaround to single-ASID sfence.vma
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
riscv-apply-sifive-cip-1200-workaround-to-single-asi.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit d0a1c5c14b31a142957239809fe302b103ec680c
Author: Samuel Holland <samuel.holland@xxxxxxxxxx>
Date: Tue Mar 26 21:49:48 2024 -0700
riscv: Apply SiFive CIP-1200 workaround to single-ASID sfence.vma
[ Upstream commit 20e03d702e00a3e0269a1d6f9549c2e370492054 ]
commit 3f1e782998cd ("riscv: add ASID-based tlbflushing methods") added
calls to the sfence.vma instruction with rs2 != x0. These single-ASID
instruction variants are also affected by SiFive errata CIP-1200.
Until now, the errata workaround was not needed for the single-ASID
sfence.vma variants, because they were only used when the ASID allocator
was enabled, and the affected SiFive platforms do not support multiple
ASIDs. However, we are going to start using those sfence.vma variants
regardless of ASID support, so now we need alternatives covering them.
Signed-off-by: Samuel Holland <samuel.holland@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240327045035.368512-8-samuel.holland@xxxxxxxxxx
Signed-off-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/riscv/include/asm/errata_list.h b/arch/riscv/include/asm/errata_list.h
index b55b434f00591..d3f3c237adad7 100644
--- a/arch/riscv/include/asm/errata_list.h
+++ b/arch/riscv/include/asm/errata_list.h
@@ -44,11 +44,21 @@ ALTERNATIVE(__stringify(RISCV_PTR do_page_fault), \
CONFIG_ERRATA_SIFIVE_CIP_453)
#else /* !__ASSEMBLY__ */
-#define ALT_FLUSH_TLB_PAGE(x) \
+#define ALT_SFENCE_VMA_ASID(asid) \
+asm(ALTERNATIVE("sfence.vma x0, %0", "sfence.vma", SIFIVE_VENDOR_ID, \
+ ERRATA_SIFIVE_CIP_1200, CONFIG_ERRATA_SIFIVE_CIP_1200) \
+ : : "r" (asid) : "memory")
+
+#define ALT_SFENCE_VMA_ADDR(addr) \
asm(ALTERNATIVE("sfence.vma %0", "sfence.vma", SIFIVE_VENDOR_ID, \
ERRATA_SIFIVE_CIP_1200, CONFIG_ERRATA_SIFIVE_CIP_1200) \
: : "r" (addr) : "memory")
+#define ALT_SFENCE_VMA_ADDR_ASID(addr, asid) \
+asm(ALTERNATIVE("sfence.vma %0, %1", "sfence.vma", SIFIVE_VENDOR_ID, \
+ ERRATA_SIFIVE_CIP_1200, CONFIG_ERRATA_SIFIVE_CIP_1200) \
+ : : "r" (addr), "r" (asid) : "memory")
+
/*
* _val is marked as "will be overwritten", so need to set it to 0
* in the default case.
diff --git a/arch/riscv/include/asm/tlbflush.h b/arch/riscv/include/asm/tlbflush.h
index 51664ae4852e7..97711d5bd8ef9 100644
--- a/arch/riscv/include/asm/tlbflush.h
+++ b/arch/riscv/include/asm/tlbflush.h
@@ -22,10 +22,27 @@ static inline void local_flush_tlb_all(void)
__asm__ __volatile__ ("sfence.vma" : : : "memory");
}
+static inline void local_flush_tlb_all_asid(unsigned long asid)
+{
+ if (asid != FLUSH_TLB_NO_ASID)
+ ALT_SFENCE_VMA_ASID(asid);
+ else
+ local_flush_tlb_all();
+}
+
/* Flush one page from local TLB */
static inline void local_flush_tlb_page(unsigned long addr)
{
- ALT_FLUSH_TLB_PAGE(__asm__ __volatile__ ("sfence.vma %0" : : "r" (addr) : "memory"));
+ ALT_SFENCE_VMA_ADDR(addr);
+}
+
+static inline void local_flush_tlb_page_asid(unsigned long addr,
+ unsigned long asid)
+{
+ if (asid != FLUSH_TLB_NO_ASID)
+ ALT_SFENCE_VMA_ADDR_ASID(addr, asid);
+ else
+ local_flush_tlb_page(addr);
}
#else /* CONFIG_MMU */
#define local_flush_tlb_all() do { } while (0)
diff --git a/arch/riscv/mm/tlbflush.c b/arch/riscv/mm/tlbflush.c
index bdee5de918e06..324e8cd9b5022 100644
--- a/arch/riscv/mm/tlbflush.c
+++ b/arch/riscv/mm/tlbflush.c
@@ -6,29 +6,6 @@
#include <asm/sbi.h>
#include <asm/mmu_context.h>
-static inline void local_flush_tlb_all_asid(unsigned long asid)
-{
- if (asid != FLUSH_TLB_NO_ASID)
- __asm__ __volatile__ ("sfence.vma x0, %0"
- :
- : "r" (asid)
- : "memory");
- else
- local_flush_tlb_all();
-}
-
-static inline void local_flush_tlb_page_asid(unsigned long addr,
- unsigned long asid)
-{
- if (asid != FLUSH_TLB_NO_ASID)
- __asm__ __volatile__ ("sfence.vma %0, %1"
- :
- : "r" (addr), "r" (asid)
- : "memory");
- else
- local_flush_tlb_page(addr);
-}
-
/*
* Flush entire TLB if number of entries to be flushed is greater
* than the threshold below.
