[PATCH v3 5/7] powerpc/pmem/of_pmem: Update of_pmem to use the new barrier instruction.

Aneesh Kumar K.V
2020-05-19T05:55:47Z

of_pmem on POWER10 can now use phwsync instead of hwsync to ensure
all previous writes are architecturally visible for the platform
buffer flush.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/include/asm/cacheflush.h | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/arch/powerpc/include/asm/cacheflush.h b/arch/powerpc/include/asm/cacheflush.h
index e92191b390f3..bc3ea009cf14 100644
--- a/arch/powerpc/include/asm/cacheflush.h
+++ b/arch/powerpc/include/asm/cacheflush.h
@@ -119,6 +119,13 @@ static inline void invalidate_dcache_range(unsigned long start,
#define copy_from_user_page(vma, page, vaddr, dst, src, len) \
memcpy(dst, src, len)

+
+#define arch_pmem_flush_barrier arch_pmem_flush_barrier
+static inline void arch_pmem_flush_barrier(void)
+{
+ if (cpu_has_feature(CPU_FTR_ARCH_207S))
+ asm volatile(PPC_PHWSYNC ::: "memory");
+}
#endif /* __KERNEL__ */

#endif /* _ASM_POWERPC_CACHEFLUSH_H */