parisc: introduce asm/swab.h

Fix for the linux/byteorder.h removal.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 66 insertions, 0 deletions

diff --git a/arch/parisc/include/asm/swab.h b/arch/parisc/include/asm/swab.h
new file mode 100644
index 000000000000..3ff16c5a3358
--- /dev/null
+++ b/arch/parisc/include/asm/swab.h
@@ -0,0 +1,66 @@
+#ifndef _PARISC_SWAB_H
+#define _PARISC_SWAB_H
+
+#include <asm/types.h>
+#include <linux/compiler.h>
+
+#define __SWAB_64_THRU_32__
+
+static inline __attribute_const__ __u16 __arch_swab16(__u16 x)
+{
+        __asm__("dep %0, 15, 8, %0\n\t"         /* deposit 00ab -> 0bab */
+                "shd %%r0, %0, 8, %0"           /* shift 000000ab -> 00ba */
+                : "=r" (x)
+                : "0" (x));
+        return x;
+}
+#define __arch_swab16 __arch_swab16
+
+static inline __attribute_const__ __u32 __arch_swab24(__u32 x)
+{
+        __asm__("shd %0, %0, 8, %0\n\t"         /* shift xabcxabc -> cxab */
+                "dep %0, 15, 8, %0\n\t"         /* deposit cxab -> cbab */
+                "shd %%r0, %0, 8, %0"           /* shift 0000cbab -> 0cba */
+                : "=r" (x)
+                : "0" (x));
+        return x;
+}
+
+static inline __attribute_const__ __u32 __arch_swab32(__u32 x)
+{
+        unsigned int temp;
+        __asm__("shd %0, %0, 16, %1\n\t"        /* shift abcdabcd -> cdab */
+                "dep %1, 15, 8, %1\n\t"         /* deposit cdab -> cbab */
+                "shd %0, %1, 8, %0"             /* shift abcdcbab -> dcba */
+                : "=r" (x), "=&r" (temp)
+                : "0" (x));
+        return x;
+}
+#define __arch_swab32 __arch_swab32
+
+#if BITS_PER_LONG > 32
+/*
+** From "PA-RISC 2.0 Architecture", HP Professional Books.
+** See Appendix I page 8 , "Endian Byte Swapping".
+**
+** Pretty cool algorithm: (* == zero'd bits)
+**      PERMH   01234567 -> 67452301 into %0
+**      HSHL    67452301 -> 7*5*3*1* into %1
+**      HSHR    67452301 -> *6*4*2*0 into %0
+**      OR      %0 | %1  -> 76543210 into %0 (all done!)
+*/
+static inline __attribute_const__ __u64 __arch_swab64(__u64 x)
+{
+        __u64 temp;
+        __asm__("permh,3210 %0, %0\n\t"
+                "hshl %0, 8, %1\n\t"
+                "hshr,u %0, 8, %0\n\t"
+                "or %1, %0, %0"
+                : "=r" (x), "=&r" (temp)
+                : "0" (x));
+        return x;
+}
+#define __arch_swab64 __arch_swab64
+#endif /* BITS_PER_LONG > 32 */
+
+#endif /* _PARISC_SWAB_H */