microblaze_v8: supported function for memory - kernel/lib
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Acked-by: John Linn <john.linn@xilinx.com>
Acked-by: John Williams <john.williams@petalogix.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>
diff --git a/arch/microblaze/lib/memcpy.c b/arch/microblaze/lib/memcpy.c
new file mode 100644
index 0000000..5880119
--- /dev/null
+++ b/arch/microblaze/lib/memcpy.c
@@ -0,0 +1,161 @@
+/*
+ * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
+ * Copyright (C) 2008-2009 PetaLogix
+ * Copyright (C) 2007 John Williams
+ *
+ * Reasonably optimised generic C-code for memcpy on Microblaze
+ * This is generic C code to do efficient, alignment-aware memcpy.
+ *
+ * It is based on demo code originally Copyright 2001 by Intel Corp, taken from
+ * http://www.embedded.com/showArticle.jhtml?articleID=19205567
+ *
+ * Attempts were made, unsuccesfully, to contact the original
+ * author of this code (Michael Morrow, Intel). Below is the original
+ * copyright notice.
+ *
+ * This software has been developed by Intel Corporation.
+ * Intel specifically disclaims all warranties, express or
+ * implied, and all liability, including consequential and
+ * other indirect damages, for the use of this program, including
+ * liability for infringement of any proprietary rights,
+ * and including the warranties of merchantability and fitness
+ * for a particular purpose. Intel does not assume any
+ * responsibility for and errors which may appear in this program
+ * not any responsibility to update it.
+ */
+
+#include <linux/types.h>
+#include <linux/stddef.h>
+#include <linux/compiler.h>
+#include <linux/module.h>
+
+#include <linux/string.h>
+#include <asm/system.h>
+
+#ifdef __HAVE_ARCH_MEMCPY
+void *memcpy(void *v_dst, const void *v_src, __kernel_size_t c)
+{
+ const char *src = v_src;
+ char *dst = v_dst;
+#ifndef CONFIG_OPT_LIB_FUNCTION
+ /* Simple, byte oriented memcpy. */
+ while (c--)
+ *dst++ = *src++;
+
+ return v_dst;
+#else
+ /* The following code tries to optimize the copy by using unsigned
+ * alignment. This will work fine if both source and destination are
+ * aligned on the same boundary. However, if they are aligned on
+ * different boundaries shifts will be necessary. This might result in
+ * bad performance on MicroBlaze systems without a barrel shifter.
+ */
+ const uint32_t *i_src;
+ uint32_t *i_dst;
+
+ if (c >= 4) {
+ unsigned value, buf_hold;
+
+ /* Align the dstination to a word boundry. */
+ /* This is done in an endian independant manner. */
+ switch ((unsigned long)dst & 3) {
+ case 1:
+ *dst++ = *src++;
+ --c;
+ case 2:
+ *dst++ = *src++;
+ --c;
+ case 3:
+ *dst++ = *src++;
+ --c;
+ }
+
+ i_dst = (void *)dst;
+
+ /* Choose a copy scheme based on the source */
+ /* alignment relative to dstination. */
+ switch ((unsigned long)src & 3) {
+ case 0x0: /* Both byte offsets are aligned */
+ i_src = (const void *)src;
+
+ for (; c >= 4; c -= 4)
+ *i_dst++ = *i_src++;
+
+ src = (const void *)i_src;
+ break;
+ case 0x1: /* Unaligned - Off by 1 */
+ /* Word align the source */
+ i_src = (const void *) ((unsigned)src & ~3);
+
+ /* Load the holding buffer */
+ buf_hold = *i_src++ << 8;
+
+ for (; c >= 4; c -= 4) {
+ value = *i_src++;
+ *i_dst++ = buf_hold | value >> 24;
+ buf_hold = value << 8;
+ }
+
+ /* Realign the source */
+ src = (const void *)i_src;
+ src -= 3;
+ break;
+ case 0x2: /* Unaligned - Off by 2 */
+ /* Word align the source */
+ i_src = (const void *) ((unsigned)src & ~3);
+
+ /* Load the holding buffer */
+ buf_hold = *i_src++ << 16;
+
+ for (; c >= 4; c -= 4) {
+ value = *i_src++;
+ *i_dst++ = buf_hold | value >> 16;
+ buf_hold = value << 16;
+ }
+
+ /* Realign the source */
+ src = (const void *)i_src;
+ src -= 2;
+ break;
+ case 0x3: /* Unaligned - Off by 3 */
+ /* Word align the source */
+ i_src = (const void *) ((unsigned)src & ~3);
+
+ /* Load the holding buffer */
+ buf_hold = *i_src++ << 24;
+
+ for (; c >= 4; c -= 4) {
+ value = *i_src++;
+ *i_dst++ = buf_hold | value >> 8;
+ buf_hold = value << 24;
+ }
+
+ /* Realign the source */
+ src = (const void *)i_src;
+ src -= 1;
+ break;
+ }
+ dst = (void *)i_dst;
+ }
+
+ /* Finish off any remaining bytes */
+ /* simple fast copy, ... unless a cache boundry is crossed */
+ switch (c) {
+ case 3:
+ *dst++ = *src++;
+ case 2:
+ *dst++ = *src++;
+ case 1:
+ *dst++ = *src++;
+ }
+
+ return v_dst;
+#endif
+}
+EXPORT_SYMBOL(memcpy);
+#endif /* __HAVE_ARCH_MEMCPY */
+
+void *cacheable_memcpy(void *d, const void *s, __kernel_size_t c)
+{
+ return memcpy(d, s, c);
+}