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authorBenjamin Herrenschmidt <benh@kernel.crashing.org>2012-11-26 09:23:57 +1100
committerBenjamin Herrenschmidt <benh@kernel.crashing.org>2012-11-26 09:23:57 +1100
commit2a859ab07b6ab66f4134c4fffc341398bd3d328c (patch)
treec5e7eaf3bffbc18feb326940e39794328d98dc07 /arch/parisc/include/uapi/asm/swab.h
parentcedddd812a79a4fda3885a15711aee3de78c4a24 (diff)
parente716e014384688d1a50d1aa5213ee74748c6d4e0 (diff)
Merge branch 'merge' into next
Merge my own merge branch to get various fixes from there and upstream, especially the hvc console tty refcouting fixes which which testing is quite a bit harder...
Diffstat (limited to 'arch/parisc/include/uapi/asm/swab.h')
-rw-r--r--arch/parisc/include/uapi/asm/swab.h66
1 files changed, 66 insertions, 0 deletions
diff --git a/arch/parisc/include/uapi/asm/swab.h b/arch/parisc/include/uapi/asm/swab.h
new file mode 100644
index 00000000000..e78403b129e
--- /dev/null
+++ b/arch/parisc/include/uapi/asm/swab.h
@@ -0,0 +1,66 @@
+#ifndef _PARISC_SWAB_H
+#define _PARISC_SWAB_H
+
+#include <linux/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 */