summaryrefslogtreecommitdiffstats
path: root/kernel/arch/blackfin/lib/memcpy.S
diff options
context:
space:
mode:
authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/blackfin/lib/memcpy.S
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/blackfin/lib/memcpy.S')
-rw-r--r--kernel/arch/blackfin/lib/memcpy.S124
1 files changed, 124 insertions, 0 deletions
diff --git a/kernel/arch/blackfin/lib/memcpy.S b/kernel/arch/blackfin/lib/memcpy.S
new file mode 100644
index 000000000..53cb3698a
--- /dev/null
+++ b/kernel/arch/blackfin/lib/memcpy.S
@@ -0,0 +1,124 @@
+/*
+ * internal version of memcpy(), issued by the compiler to copy blocks of
+ * data around. This is really memmove() - it has to be able to deal with
+ * possible overlaps, because that ambiguity is when the compiler gives up
+ * and calls a function. We have our own, internal version so that we get
+ * something we trust, even if the user has redefined the normal symbol.
+ *
+ * Copyright 2004-2009 Analog Devices Inc.
+ *
+ * Licensed under the Clear BSD license or the GPL-2 (or later)
+ */
+
+#include <linux/linkage.h>
+
+/* void *memcpy(void *dest, const void *src, size_t n);
+ * R0 = To Address (dest) (leave unchanged to form result)
+ * R1 = From Address (src)
+ * R2 = count
+ *
+ * Note: Favours word alignment
+ */
+
+#ifdef CONFIG_MEMCPY_L1
+.section .l1.text
+#else
+.text
+#endif
+
+.align 2
+
+ENTRY(_memcpy)
+ CC = R2 <= 0; /* length not positive? */
+ IF CC JUMP .L_P1L2147483647; /* Nothing to do */
+
+ P0 = R0 ; /* dst*/
+ P1 = R1 ; /* src*/
+ P2 = R2 ; /* length */
+
+ /* check for overlapping data */
+ CC = R1 < R0; /* src < dst */
+ IF !CC JUMP .Lno_overlap;
+ R3 = R1 + R2;
+ CC = R0 < R3; /* and dst < src+len */
+ IF CC JUMP .Lhas_overlap;
+
+.Lno_overlap:
+ /* Check for aligned data.*/
+
+ R3 = R1 | R0;
+ R1 = 0x3;
+ R3 = R3 & R1;
+ CC = R3; /* low bits set on either address? */
+ IF CC JUMP .Lnot_aligned;
+
+ /* Both addresses are word-aligned, so we can copy
+ at least part of the data using word copies.*/
+ P2 = P2 >> 2;
+ CC = P2 <= 2;
+ IF !CC JUMP .Lmore_than_seven;
+ /* less than eight bytes... */
+ P2 = R2;
+ LSETUP(.Lthree_start, .Lthree_end) LC0=P2;
+.Lthree_start:
+ R3 = B[P1++] (X);
+.Lthree_end:
+ B[P0++] = R3;
+
+ RTS;
+
+.Lmore_than_seven:
+ /* There's at least eight bytes to copy. */
+ P2 += -1; /* because we unroll one iteration */
+ LSETUP(.Lword_loops, .Lword_loope) LC0=P2;
+ I1 = P1;
+ R3 = [I1++];
+#if ANOMALY_05000202
+.Lword_loops:
+ [P0++] = R3;
+.Lword_loope:
+ R3 = [I1++];
+#else
+.Lword_loops:
+.Lword_loope:
+ MNOP || [P0++] = R3 || R3 = [I1++];
+#endif
+ [P0++] = R3;
+ /* Any remaining bytes to copy? */
+ R3 = 0x3;
+ R3 = R2 & R3;
+ CC = R3 == 0;
+ P1 = I1; /* in case there's something left, */
+ IF !CC JUMP .Lbytes_left;
+ RTS;
+.Lbytes_left: P2 = R3;
+.Lnot_aligned:
+ /* From here, we're copying byte-by-byte. */
+ LSETUP (.Lbyte_start, .Lbyte_end) LC0=P2;
+.Lbyte_start:
+ R1 = B[P1++] (X);
+.Lbyte_end:
+ B[P0++] = R1;
+
+.L_P1L2147483647:
+ RTS;
+
+.Lhas_overlap:
+ /* Need to reverse the copying, because the
+ * dst would clobber the src.
+ * Don't bother to work out alignment for
+ * the reverse case.
+ */
+ P0 = P0 + P2;
+ P0 += -1;
+ P1 = P1 + P2;
+ P1 += -1;
+ LSETUP(.Lover_start, .Lover_end) LC0=P2;
+.Lover_start:
+ R1 = B[P1--] (X);
+.Lover_end:
+ B[P0--] = R1;
+
+ RTS;
+
+ENDPROC(_memcpy)