Le 19/10/2017 à 09:13, Oliver O'Halloran a écrit :
Implement the architecture specific cache maintence functions that make
up the "PMEM API". Currently the writeback and invalidate functions
are the same since the function of the DCBST (data cache block store)
instruction is typically interpreted as "writeback to the point of
coherency" rather than to memory. As a result implementing the API
requires a full cache flush rather than just a cache write back. This
will probably change in the not-too-distant future.
Signed-off-by: Oliver O'Halloran <ooh...@gmail.com>
---
arch/powerpc/Kconfig | 1 +
arch/powerpc/lib/Makefile | 2 +-
arch/powerpc/lib/pmem.c | 34 ++++++++++++++++++++++++++++++++++
3 files changed, 36 insertions(+), 1 deletion(-)
create mode 100644 arch/powerpc/lib/pmem.c
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 809c468edab1..0996add8a572 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -138,6 +138,7 @@ config PPC
select ARCH_HAS_ELF_RANDOMIZE
select ARCH_HAS_FORTIFY_SOURCE
select ARCH_HAS_GCOV_PROFILE_ALL
+ select ARCH_HAS_PMEM_API if PPC64
Why restrict that to PPC64 ?
select ARCH_HAS_SCALED_CPUTIME if VIRT_CPU_ACCOUNTING_NATIVE
select ARCH_HAS_SG_CHAIN
select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
diff --git a/arch/powerpc/lib/Makefile b/arch/powerpc/lib/Makefile
index 50d5bf954cff..7aa237d10546 100644
--- a/arch/powerpc/lib/Makefile
+++ b/arch/powerpc/lib/Makefile
@@ -23,7 +23,7 @@ endif
obj64-y += copypage_64.o copyuser_64.o mem_64.o hweight_64.o \
copyuser_power7.o string_64.o copypage_power7.o memcpy_power7.o \
- memcpy_64.o memcmp_64.o
+ memcpy_64.o memcmp_64.o pmem.o
obj64-$(CONFIG_SMP) += locks.o
obj64-$(CONFIG_ALTIVEC) += vmx-helper.o
diff --git a/arch/powerpc/lib/pmem.c b/arch/powerpc/lib/pmem.c
new file mode 100644
index 000000000000..0fa09262ca13
--- /dev/null
+++ b/arch/powerpc/lib/pmem.c
@@ -0,0 +1,34 @@
+/*
+ * Copyright(c) 2017 IBM Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+
+#include <linux/string.h>
+#include <linux/export.h>
+
+#include <asm/cacheflush.h>
+
+/*
+ * CONFIG_ARCH_HAS_PMEM_API symbols
+ */
+void arch_wb_cache_pmem(void *addr, size_t size)
+{
+ unsigned long start = (unsigned long) addr;
+ flush_inval_dcache_range(start, start + size);
That function seems to only exist in PPC64, however a quite similar one,
called flush_dcache_range() does the same on PPC32 (defined in
arch/powerpc/include/asm/cacheflush.h)
In the meantime, I see that PPC64 also has a function called
flush_dcache_range(), which does the same as PPC32 function
clean_dcache_range()
Maybe she should re-unify the names ?
Christophe
+}
+EXPORT_SYMBOL(arch_wb_cache_pmem);
+
+void arch_invalidate_pmem(void *addr, size_t size)
+{
+ unsigned long start = (unsigned long) addr;
+ flush_inval_dcache_range(start, start + size);
+}
+EXPORT_SYMBOL(arch_invalidate_pmem);
