* [PATCH 2/2] powerpc/pmem: Add flush routines using new pmem store and sync instruction
2020-05-11 11:34 [PATCH 1/2] powerpc/pmem: Add new instructions for persistent storage and sync Aneesh Kumar K.V
@ 2020-05-11 11:34 ` Aneesh Kumar K.V
0 siblings, 0 replies; 2+ messages in thread
From: Aneesh Kumar K.V @ 2020-05-11 11:34 UTC (permalink / raw)
To: linuxppc-dev, mpe; +Cc: alistair, oohall, Aneesh Kumar K.V
Start using dcbstps; phwsync; sequence for flushing persistent memory range.
The new instructions are implemented as a variant of dcbf and hwsync and on
POWER9 they will be executed as those instructions.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
arch/powerpc/include/asm/cacheflush.h | 31 +++++++++++++++++++++++++++
arch/powerpc/lib/pmem.c | 8 +++----
2 files changed, 35 insertions(+), 4 deletions(-)
diff --git a/arch/powerpc/include/asm/cacheflush.h b/arch/powerpc/include/asm/cacheflush.h
index e92191b390f3..edb59edeeacb 100644
--- a/arch/powerpc/include/asm/cacheflush.h
+++ b/arch/powerpc/include/asm/cacheflush.h
@@ -74,6 +74,37 @@ static inline void flush_dcache_range(unsigned long start, unsigned long stop)
}
+static inline void clean_pmem_range(unsigned long start, unsigned long stop)
+{
+ unsigned long shift = l1_dcache_shift();
+ unsigned long bytes = l1_dcache_bytes();
+ void *addr = (void *)(start & ~(bytes - 1));
+ unsigned long size = stop - (unsigned long)addr + (bytes - 1);
+ unsigned long i;
+
+ for (i = 0; i < size >> shift; i++, addr += bytes)
+ asm volatile(PPC_DCBSTPS(%0, %1): :"i"(0), "r"(addr): "memory");
+
+
+ asm volatile(PPC_PHWSYNC():::"memory");
+}
+
+static inline void flush_pmem_range(unsigned long start, unsigned long stop)
+{
+ unsigned long shift = l1_dcache_shift();
+ unsigned long bytes = l1_dcache_bytes();
+ void *addr = (void *)(start & ~(bytes - 1));
+ unsigned long size = stop - (unsigned long)addr + (bytes - 1);
+ unsigned long i;
+
+ for (i = 0; i < size >> shift; i++, addr += bytes)
+ asm volatile(PPC_DCBFPS(%0, %1): :"i"(0), "r"(addr): "memory");
+
+
+ asm volatile(PPC_PHWSYNC():::"memory");
+}
+
+
/*
* Write any modified data cache blocks out to memory.
* Does not invalidate the corresponding cache lines (especially for
diff --git a/arch/powerpc/lib/pmem.c b/arch/powerpc/lib/pmem.c
index 0666a8d29596..624708bcaaad 100644
--- a/arch/powerpc/lib/pmem.c
+++ b/arch/powerpc/lib/pmem.c
@@ -15,14 +15,14 @@
void arch_wb_cache_pmem(void *addr, size_t size)
{
unsigned long start = (unsigned long) addr;
- flush_dcache_range(start, start + size);
+ clean_pmem_range(start, start + size);
}
EXPORT_SYMBOL_GPL(arch_wb_cache_pmem);
void arch_invalidate_pmem(void *addr, size_t size)
{
unsigned long start = (unsigned long) addr;
- flush_dcache_range(start, start + size);
+ flush_pmem_range(start, start + size);
}
EXPORT_SYMBOL_GPL(arch_invalidate_pmem);
@@ -35,7 +35,7 @@ long __copy_from_user_flushcache(void *dest, const void __user *src,
unsigned long copied, start = (unsigned long) dest;
copied = __copy_from_user(dest, src, size);
- flush_dcache_range(start, start + size);
+ clean_pmem_range(start, start + size);
return copied;
}
@@ -45,7 +45,7 @@ void *memcpy_flushcache(void *dest, const void *src, size_t size)
unsigned long start = (unsigned long) dest;
memcpy(dest, src, size);
- flush_dcache_range(start, start + size);
+ clean_pmem_range(start, start + size);
return dest;
}
--
2.26.2
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