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-rw-r--r--arch/v850/lib/memcpy.c92
1 files changed, 92 insertions, 0 deletions
diff --git a/arch/v850/lib/memcpy.c b/arch/v850/lib/memcpy.c
new file mode 100644
index 00000000000..492847b3e61
--- /dev/null
+++ b/arch/v850/lib/memcpy.c
@@ -0,0 +1,92 @@
+/*
+ * arch/v850/lib/memcpy.c -- Memory copying
+ *
+ * Copyright (C) 2001,02 NEC Corporation
+ * Copyright (C) 2001,02 Miles Bader <miles@gnu.org>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file COPYING in the main directory of this
+ * archive for more details.
+ *
+ * Written by Miles Bader <miles@gnu.org>
+ */
+
+#include <linux/types.h>
+#include <asm/string.h>
+
+#define CHUNK_SIZE 32 /* bytes */
+#define CHUNK_ALIGNED(addr) (((unsigned long)addr & 0x3) == 0)
+
+/* Note that this macro uses 8 call-clobbered registers (not including
+ R1), which are few enough so that the following functions don't need
+ to spill anything to memory. It also uses R1, which is nominally
+ reserved for the assembler, but here it should be OK. */
+#define COPY_CHUNK(src, dst) \
+ asm ("mov %0, ep;" \
+ "sld.w 0[ep], r1; sld.w 4[ep], r12;" \
+ "sld.w 8[ep], r13; sld.w 12[ep], r14;" \
+ "sld.w 16[ep], r15; sld.w 20[ep], r17;" \
+ "sld.w 24[ep], r18; sld.w 28[ep], r19;" \
+ "mov %1, ep;" \
+ "sst.w r1, 0[ep]; sst.w r12, 4[ep];" \
+ "sst.w r13, 8[ep]; sst.w r14, 12[ep];" \
+ "sst.w r15, 16[ep]; sst.w r17, 20[ep];" \
+ "sst.w r18, 24[ep]; sst.w r19, 28[ep]" \
+ :: "r" (src), "r" (dst) \
+ : "r1", "r12", "r13", "r14", "r15", \
+ "r17", "r18", "r19", "ep", "memory");
+
+void *memcpy (void *dst, const void *src, __kernel_size_t size)
+{
+ char *_dst = dst;
+ const char *_src = src;
+
+ if (size >= CHUNK_SIZE && CHUNK_ALIGNED(_src) && CHUNK_ALIGNED(_dst)) {
+ /* Copy large blocks efficiently. */
+ unsigned count;
+ for (count = size / CHUNK_SIZE; count; count--) {
+ COPY_CHUNK (_src, _dst);
+ _src += CHUNK_SIZE;
+ _dst += CHUNK_SIZE;
+ }
+ size %= CHUNK_SIZE;
+ }
+
+ if (size > 0)
+ do
+ *_dst++ = *_src++;
+ while (--size);
+
+ return dst;
+}
+
+void *memmove (void *dst, const void *src, __kernel_size_t size)
+{
+ if ((unsigned long)dst < (unsigned long)src
+ || (unsigned long)src + size < (unsigned long)dst)
+ return memcpy (dst, src, size);
+ else {
+ char *_dst = dst + size;
+ const char *_src = src + size;
+
+ if (size >= CHUNK_SIZE
+ && CHUNK_ALIGNED (_src) && CHUNK_ALIGNED (_dst))
+ {
+ /* Copy large blocks efficiently. */
+ unsigned count;
+ for (count = size / CHUNK_SIZE; count; count--) {
+ _src -= CHUNK_SIZE;
+ _dst -= CHUNK_SIZE;
+ COPY_CHUNK (_src, _dst);
+ }
+ size %= CHUNK_SIZE;
+ }
+
+ if (size > 0)
+ do
+ *--_dst = *--_src;
+ while (--size);
+
+ return _dst;
+ }
+}