From: Suresh Warrier <warr...@linux.vnet.ibm.com>
Add simple cache inhibited accessors for memory mapped I/O.
Unlike the accessors built from the DEF_MMIO_* macros, these
don't include any hardware memory barriers, callers need to
manage memory barriers on their own. These can only be called
in hypervisor real mode.
Signed-off-by: Suresh Warrier <warr...@linux.vnet.ibm.com>
[pau...@ozlabs.org - added line to comment]
Signed-off-by: Paul Mackerras <pau...@ozlabs.org>
---
arch/powerpc/include/asm/io.h | 29 +++++++++++++++++++++++++++++
1 file changed, 29 insertions(+)
diff --git a/arch/powerpc/include/asm/io.h b/arch/powerpc/include/asm/io.h
index 2fd1690..f6fda84 100644
--- a/arch/powerpc/include/asm/io.h
+++ b/arch/powerpc/include/asm/io.h
@@ -241,6 +241,35 @@ static inline void out_be64(volatile u64 __iomem *addr,
u64 val)
#endif
#endif /* __powerpc64__ */
+
+/*
+ * Simple Cache inhibited accessors
+ * Unlike the DEF_MMIO_* macros, these don't include any h/w memory
+ * barriers, callers need to manage memory barriers on their own.
+ * These can only be used in hypervisor real mode.
+ */
+
+static inline u32 _lwzcix(unsigned long addr)
+{
+ u32 ret;
+
+ __asm__ __volatile__("lwzcix %0,0, %1"
+ : "=r" (ret) : "r" (addr) : "memory");
+ return ret;
+}
+
+static inline void _stbcix(u64 addr, u8 val)
+{
+ __asm__ __volatile__("stbcix %0,0,%1"
+ : : "r" (val), "r" (addr) : "memory");
+}
+
+static inline void _stwcix(u64 addr, u32 val)
+{
+ __asm__ __volatile__("stwcix %0,0,%1"
+ : : "r" (val), "r" (addr) : "memory");
+}
+
/*
* Low level IO stream instructions are defined out of line for now
*/
--
2.8.1
