9 files changed, 1620 insertions, 69 deletions

diff --git a/arch/arm64/lib/Makefile b/arch/arm64/lib/Makefile
index 328ce1a99daa..d98d3e39879e 100644
--- a/arch/arm64/lib/Makefile
+++ b/arch/arm64/lib/Makefile
@@ -1,4 +1,5 @@
 lib-y		:= bitops.o clear_user.o delay.o copy_from_user.o	\
 		   copy_to_user.o copy_in_user.o copy_page.o		\
 		   clear_page.o memchr.o memcpy.o memmove.o memset.o	\
+		   memcmp.o strcmp.o strncmp.o strlen.o strnlen.o	\
 		   strchr.o strrchr.o
diff --git a/arch/arm64/lib/memcmp.S b/arch/arm64/lib/memcmp.S
new file mode 100644
index 000000000000..6ea0776ba6de
--- /dev/null
+++ b/arch/arm64/lib/memcmp.S
@@ -0,0 +1,258 @@
+/*
+ * Copyright (C) 2013 ARM Ltd.
+ * Copyright (C) 2013 Linaro.
+ *
+ * This code is based on glibc cortex strings work originally authored by Linaro
+ * and re-licensed under GPLv2 for the Linux kernel. The original code can
+ * be found @
+ *
+ * http://bazaar.launchpad.net/~linaro-toolchain-dev/cortex-strings/trunk/
+ * files/head:/src/aarch64/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+/*
+* compare memory areas(when two memory areas' offset are different,
+* alignment handled by the hardware)
+*
+* Parameters:
+*  x0 - const memory area 1 pointer
+*  x1 - const memory area 2 pointer
+*  x2 - the maximal compare byte length
+* Returns:
+*  x0 - a compare result, maybe less than, equal to, or greater than ZERO
+*/
+
+/* Parameters and result.  */
+src1		.req	x0
+src2		.req	x1
+limit		.req	x2
+result		.req	x0
+
+/* Internal variables.  */
+data1		.req	x3
+data1w		.req	w3
+data2		.req	x4
+data2w		.req	w4
+has_nul		.req	x5
+diff		.req	x6
+endloop		.req	x7
+tmp1		.req	x8
+tmp2		.req	x9
+tmp3		.req	x10
+pos		.req	x11
+limit_wd	.req	x12
+mask		.req	x13
+
+ENTRY(memcmp)
+	cbz	limit, .Lret0
+	eor	tmp1, src1, src2
+	tst	tmp1, #7
+	b.ne	.Lmisaligned8
+	ands	tmp1, src1, #7
+	b.ne	.Lmutual_align
+	sub	limit_wd, limit, #1 /* limit != 0, so no underflow.  */
+	lsr	limit_wd, limit_wd, #3 /* Convert to Dwords.  */
+	/*
+	* The input source addresses are at alignment boundary.
+	* Directly compare eight bytes each time.
+	*/
+.Lloop_aligned:
+	ldr	data1, [src1], #8
+	ldr	data2, [src2], #8
+.Lstart_realigned:
+	subs	limit_wd, limit_wd, #1
+	eor	diff, data1, data2	/* Non-zero if differences found.  */
+	csinv	endloop, diff, xzr, cs	/* Last Dword or differences.  */
+	cbz	endloop, .Lloop_aligned
+
+	/* Not reached the limit, must have found a diff.  */
+	tbz	limit_wd, #63, .Lnot_limit
+
+	/* Limit % 8 == 0 => the diff is in the last 8 bytes. */
+	ands	limit, limit, #7
+	b.eq	.Lnot_limit
+	/*
+	* The remained bytes less than 8. It is needed to extract valid data
+	* from last eight bytes of the intended memory range.
+	*/
+	lsl	limit, limit, #3	/* bytes-> bits.  */
+	mov	mask, #~0
+CPU_BE( lsr	mask, mask, limit )
+CPU_LE( lsl	mask, mask, limit )
+	bic	data1, data1, mask
+	bic	data2, data2, mask
+
+	orr	diff, diff, mask
+	b	.Lnot_limit
+
+.Lmutual_align:
+	/*
+	* Sources are mutually aligned, but are not currently at an
+	* alignment boundary. Round down the addresses and then mask off
+	* the bytes that precede the start point.
+	*/
+	bic	src1, src1, #7
+	bic	src2, src2, #7
+	ldr	data1, [src1], #8
+	ldr	data2, [src2], #8
+	/*
+	* We can not add limit with alignment offset(tmp1) here. Since the
+	* addition probably make the limit overflown.
+	*/
+	sub	limit_wd, limit, #1/*limit != 0, so no underflow.*/
+	and	tmp3, limit_wd, #7
+	lsr	limit_wd, limit_wd, #3
+	add	tmp3, tmp3, tmp1
+	add	limit_wd, limit_wd, tmp3, lsr #3
+	add	limit, limit, tmp1/* Adjust the limit for the extra.  */
+
+	lsl	tmp1, tmp1, #3/* Bytes beyond alignment -> bits.*/
+	neg	tmp1, tmp1/* Bits to alignment -64.  */
+	mov	tmp2, #~0
+	/*mask off the non-intended bytes before the start address.*/
+CPU_BE( lsl	tmp2, tmp2, tmp1 )/*Big-endian.Early bytes are at MSB*/
+	/* Little-endian.  Early bytes are at LSB.  */
+CPU_LE( lsr	tmp2, tmp2, tmp1 )
+
+	orr	data1, data1, tmp2
+	orr	data2, data2, tmp2
+	b	.Lstart_realigned
+
+	/*src1 and src2 have different alignment offset.*/
+.Lmisaligned8:
+	cmp	limit, #8
+	b.lo	.Ltiny8proc /*limit < 8: compare byte by byte*/
+
+	and	tmp1, src1, #7
+	neg	tmp1, tmp1
+	add	tmp1, tmp1, #8/*valid length in the first 8 bytes of src1*/
+	and	tmp2, src2, #7
+	neg	tmp2, tmp2
+	add	tmp2, tmp2, #8/*valid length in the first 8 bytes of src2*/
+	subs	tmp3, tmp1, tmp2
+	csel	pos, tmp1, tmp2, hi /*Choose the maximum.*/
+
+	sub	limit, limit, pos
+	/*compare the proceeding bytes in the first 8 byte segment.*/
+.Ltinycmp:
+	ldrb	data1w, [src1], #1
+	ldrb	data2w, [src2], #1
+	subs	pos, pos, #1
+	ccmp	data1w, data2w, #0, ne  /* NZCV = 0b0000.  */
+	b.eq	.Ltinycmp
+	cbnz	pos, 1f /*diff occurred before the last byte.*/
+	cmp	data1w, data2w
+	b.eq	.Lstart_align
+1:
+	sub	result, data1, data2
+	ret
+
+.Lstart_align:
+	lsr	limit_wd, limit, #3
+	cbz	limit_wd, .Lremain8
+
+	ands	xzr, src1, #7
+	b.eq	.Lrecal_offset
+	/*process more leading bytes to make src1 aligned...*/
+	add	src1, src1, tmp3 /*backwards src1 to alignment boundary*/
+	add	src2, src2, tmp3
+	sub	limit, limit, tmp3
+	lsr	limit_wd, limit, #3
+	cbz	limit_wd, .Lremain8
+	/*load 8 bytes from aligned SRC1..*/
+	ldr	data1, [src1], #8
+	ldr	data2, [src2], #8
+
+	subs	limit_wd, limit_wd, #1
+	eor	diff, data1, data2  /*Non-zero if differences found.*/
+	csinv	endloop, diff, xzr, ne
+	cbnz	endloop, .Lunequal_proc
+	/*How far is the current SRC2 from the alignment boundary...*/
+	and	tmp3, tmp3, #7
+
+.Lrecal_offset:/*src1 is aligned now..*/
+	neg	pos, tmp3
+.Lloopcmp_proc:
+	/*
+	* Divide the eight bytes into two parts. First,backwards the src2
+	* to an alignment boundary,load eight bytes and compare from
+	* the SRC2 alignment boundary. If all 8 bytes are equal,then start
+	* the second part's comparison. Otherwise finish the comparison.
+	* This special handle can garantee all the accesses are in the
+	* thread/task space in avoid to overrange access.
+	*/
+	ldr	data1, [src1,pos]
+	ldr	data2, [src2,pos]
+	eor	diff, data1, data2  /* Non-zero if differences found.  */
+	cbnz	diff, .Lnot_limit
+
+	/*The second part process*/
+	ldr	data1, [src1], #8
+	ldr	data2, [src2], #8
+	eor	diff, data1, data2  /* Non-zero if differences found.  */
+	subs	limit_wd, limit_wd, #1
+	csinv	endloop, diff, xzr, ne/*if limit_wd is 0,will finish the cmp*/
+	cbz	endloop, .Lloopcmp_proc
+.Lunequal_proc:
+	cbz	diff, .Lremain8
+
+/*There is differnence occured in the latest comparison.*/
+.Lnot_limit:
+/*
+* For little endian,reverse the low significant equal bits into MSB,then
+* following CLZ can find how many equal bits exist.
+*/
+CPU_LE( rev	diff, diff )
+CPU_LE( rev	data1, data1 )
+CPU_LE( rev	data2, data2 )
+
+	/*
+	* The MS-non-zero bit of DIFF marks either the first bit
+	* that is different, or the end of the significant data.
+	* Shifting left now will bring the critical information into the
+	* top bits.
+	*/
+	clz	pos, diff
+	lsl	data1, data1, pos
+	lsl	data2, data2, pos
+	/*
+	* We need to zero-extend (char is unsigned) the value and then
+	* perform a signed subtraction.
+	*/
+	lsr	data1, data1, #56
+	sub	result, data1, data2, lsr #56
+	ret
+
+.Lremain8:
+	/* Limit % 8 == 0 =>. all data are equal.*/
+	ands	limit, limit, #7
+	b.eq	.Lret0
+
+.Ltiny8proc:
+	ldrb	data1w, [src1], #1
+	ldrb	data2w, [src2], #1
+	subs	limit, limit, #1
+
+	ccmp	data1w, data2w, #0, ne  /* NZCV = 0b0000. */
+	b.eq	.Ltiny8proc
+	sub	result, data1, data2
+	ret
+.Lret0:
+	mov	result, #0
+	ret
+ENDPROC(memcmp)
diff --git a/arch/arm64/lib/memcpy.S b/arch/arm64/lib/memcpy.S
index 27b5003609b6..8a9a96d3ddae 100644
--- a/arch/arm64/lib/memcpy.S
+++ b/arch/arm64/lib/memcpy.S
@@ -1,5 +1,13 @@
 /*
  * Copyright (C) 2013 ARM Ltd.
+ * Copyright (C) 2013 Linaro.
+ *
+ * This code is based on glibc cortex strings work originally authored by Linaro
+ * and re-licensed under GPLv2 for the Linux kernel. The original code can
+ * be found @
+ *
+ * http://bazaar.launchpad.net/~linaro-toolchain-dev/cortex-strings/trunk/
+ * files/head:/src/aarch64/
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -16,6 +24,7 @@
 
 #include <linux/linkage.h>
 #include <asm/assembler.h>
+#include <asm/cache.h>
 
 /*
  * Copy a buffer from src to dest (alignment handled by the hardware)
@@ -27,27 +36,166 @@
  * Returns:
  *	x0 - dest
  */
+dstin	.req	x0
+src	.req	x1
+count	.req	x2
+tmp1	.req	x3
+tmp1w	.req	w3
+tmp2	.req	x4
+tmp2w	.req	w4
+tmp3	.req	x5
+tmp3w	.req	w5
+dst	.req	x6
+
+A_l	.req	x7
+A_h	.req	x8
+B_l	.req	x9
+B_h	.req	x10
+C_l	.req	x11
+C_h	.req	x12
+D_l	.req	x13
+D_h	.req	x14
+
 ENTRY(memcpy)
-	mov	x4, x0
-	subs	x2, x2, #8
-	b.mi	2f
-1:	ldr	x3, [x1], #8
-	subs	x2, x2, #8
-	str	x3, [x4], #8
-	b.pl	1b
-2:	adds	x2, x2, #4
-	b.mi	3f
-	ldr	w3, [x1], #4
-	sub	x2, x2, #4
-	str	w3, [x4], #4
-3:	adds	x2, x2, #2
-	b.mi	4f
-	ldrh	w3, [x1], #2
-	sub	x2, x2, #2
-	strh	w3, [x4], #2
-4:	adds	x2, x2, #1
-	b.mi	5f
-	ldrb	w3, [x1]
-	strb	w3, [x4]
-5:	ret
+	mov	dst, dstin
+	cmp	count, #16
+	/*When memory length is less than 16, the accessed are not aligned.*/
+	b.lo	.Ltiny15
+
+	neg	tmp2, src
+	ands	tmp2, tmp2, #15/* Bytes to reach alignment. */
+	b.eq	.LSrcAligned
+	sub	count, count, tmp2
+	/*
+	* Copy the leading memory data from src to dst in an increasing
+	* address order.By this way,the risk of overwritting the source
+	* memory data is eliminated when the distance between src and
+	* dst is less than 16. The memory accesses here are alignment.
+	*/
+	tbz	tmp2, #0, 1f
+	ldrb	tmp1w, [src], #1
+	strb	tmp1w, [dst], #1
+1:
+	tbz	tmp2, #1, 2f
+	ldrh	tmp1w, [src], #2
+	strh	tmp1w, [dst], #2
+2:
+	tbz	tmp2, #2, 3f
+	ldr	tmp1w, [src], #4
+	str	tmp1w, [dst], #4
+3:
+	tbz	tmp2, #3, .LSrcAligned
+	ldr	tmp1, [src],#8
+	str	tmp1, [dst],#8
+
+.LSrcAligned:
+	cmp	count, #64
+	b.ge	.Lcpy_over64
+	/*
+	* Deal with small copies quickly by dropping straight into the
+	* exit block.
+	*/
+.Ltail63:
+	/*
+	* Copy up to 48 bytes of data. At this point we only need the
+	* bottom 6 bits of count to be accurate.
+	*/
+	ands	tmp1, count, #0x30
+	b.eq	.Ltiny15
+	cmp	tmp1w, #0x20
+	b.eq	1f
+	b.lt	2f
+	ldp	A_l, A_h, [src], #16
+	stp	A_l, A_h, [dst], #16
+1:
+	ldp	A_l, A_h, [src], #16
+	stp	A_l, A_h, [dst], #16
+2:
+	ldp	A_l, A_h, [src], #16
+	stp	A_l, A_h, [dst], #16
+.Ltiny15:
+	/*
+	* Prefer to break one ldp/stp into several load/store to access
+	* memory in an increasing address order,rather than to load/store 16
+	* bytes from (src-16) to (dst-16) and to backward the src to aligned
+	* address,which way is used in original cortex memcpy. If keeping
+	* the original memcpy process here, memmove need to satisfy the
+	* precondition that src address is at least 16 bytes bigger than dst
+	* address,otherwise some source data will be overwritten when memove
+	* call memcpy directly. To make memmove simpler and decouple the
+	* memcpy's dependency on memmove, withdrew the original process.
+	*/
+	tbz	count, #3, 1f
+	ldr	tmp1, [src], #8
+	str	tmp1, [dst], #8
+1:
+	tbz	count, #2, 2f
+	ldr	tmp1w, [src], #4
+	str	tmp1w, [dst], #4
+2:
+	tbz	count, #1, 3f
+	ldrh	tmp1w, [src], #2
+	strh	tmp1w, [dst], #2
+3:
+	tbz	count, #0, .Lexitfunc
+	ldrb	tmp1w, [src]
+	strb	tmp1w, [dst]
+
+.Lexitfunc:
+	ret
+
+.Lcpy_over64:
+	subs	count, count, #128
+	b.ge	.Lcpy_body_large
+	/*
+	* Less than 128 bytes to copy, so handle 64 here and then jump
+	* to the tail.
+	*/
+	ldp	A_l, A_h, [src],#16
+	stp	A_l, A_h, [dst],#16
+	ldp	B_l, B_h, [src],#16
+	ldp	C_l, C_h, [src],#16
+	stp	B_l, B_h, [dst],#16
+	stp	C_l, C_h, [dst],#16
+	ldp	D_l, D_h, [src],#16
+	stp	D_l, D_h, [dst],#16
+
+	tst	count, #0x3f
+	b.ne	.Ltail63
+	ret
+
+	/*
+	* Critical loop.  Start at a new cache line boundary.  Assuming
+	* 64 bytes per line this ensures the entire loop is in one line.
+	*/
+	.p2align	L1_CACHE_SHIFT
+.Lcpy_body_large:
+	/* pre-get 64 bytes data. */
+	ldp	A_l, A_h, [src],#16
+	ldp	B_l, B_h, [src],#16
+	ldp	C_l, C_h, [src],#16
+	ldp	D_l, D_h, [src],#16
+1:
+	/*
+	* interlace the load of next 64 bytes data block with store of the last
+	* loaded 64 bytes data.
+	*/
+	stp	A_l, A_h, [dst],#16
+	ldp	A_l, A_h, [src],#16
+	stp	B_l, B_h, [dst],#16
+	ldp	B_l, B_h, [src],#16
+	stp	C_l, C_h, [dst],#16
+	ldp	C_l, C_h, [src],#16
+	stp	D_l, D_h, [dst],#16
+	ldp	D_l, D_h, [src],#16
+	subs	count, count, #64
+	b.ge	1b
+	stp	A_l, A_h, [dst],#16
+	stp	B_l, B_h, [dst],#16
+	stp	C_l, C_h, [dst],#16
+	stp	D_l, D_h, [dst],#16
+
+	tst	count, #0x3f
+	b.ne	.Ltail63
+	ret
 ENDPROC(memcpy)
diff --git a/arch/arm64/lib/memmove.S b/arch/arm64/lib/memmove.S
index b79fdfa42d39..57b19ea2dad4 100644
--- a/arch/arm64/lib/memmove.S
+++ b/arch/arm64/lib/memmove.S
@@ -1,5 +1,13 @@
 /*
  * Copyright (C) 2013 ARM Ltd.
+ * Copyright (C) 2013 Linaro.
+ *
+ * This code is based on glibc cortex strings work originally authored by Linaro
+ * and re-licensed under GPLv2 for the Linux kernel. The original code can
+ * be found @
+ *
+ * http://bazaar.launchpad.net/~linaro-toolchain-dev/cortex-strings/trunk/
+ * files/head:/src/aarch64/
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -16,6 +24,7 @@
 
 #include <linux/linkage.h>
 #include <asm/assembler.h>
+#include <asm/cache.h>
 
 /*
  * Move a buffer from src to test (alignment handled by the hardware).
@@ -28,30 +37,161 @@
  * Returns:
  *	x0 - dest
  */
+dstin	.req	x0
+src	.req	x1
+count	.req	x2
+tmp1	.req	x3
+tmp1w	.req	w3
+tmp2	.req	x4
+tmp2w	.req	w4
+tmp3	.req	x5
+tmp3w	.req	w5
+dst	.req	x6
+
+A_l	.req	x7
+A_h	.req	x8
+B_l	.req	x9
+B_h	.req	x10
+C_l	.req	x11
+C_h	.req	x12
+D_l	.req	x13
+D_h	.req	x14
+
 ENTRY(memmove)
-	cmp	x0, x1
-	b.ls	memcpy
-	add	x4, x0, x2
-	add	x1, x1, x2
-	subs	x2, x2, #8
-	b.mi	2f
-1:	ldr	x3, [x1, #-8]!
-	subs	x2, x2, #8
-	str	x3, [x4, #-8]!
-	b.pl	1b
-2:	adds	x2, x2, #4
-	b.mi	3f
-	ldr	w3, [x1, #-4]!
-	sub	x2, x2, #4
-	str	w3, [x4, #-4]!
-3:	adds	x2, x2, #2
-	b.mi	4f
-	ldrh	w3, [x1, #-2]!
-	sub	x2, x2, #2
-	strh	w3, [x4, #-2]!
-4:	adds	x2, x2, #1
-	b.mi	5f
-	ldrb	w3, [x1, #-1]
-	strb	w3, [x4, #-1]
-5:	ret
+	cmp	dstin, src
+	b.lo	memcpy
+	add	tmp1, src, count
+	cmp	dstin, tmp1
+	b.hs	memcpy		/* No overlap.  */
+
+	add	dst, dstin, count
+	add	src, src, count
+	cmp	count, #16
+	b.lo	.Ltail15  /*probably non-alignment accesses.*/
+
+	ands	tmp2, src, #15     /* Bytes to reach alignment.  */
+	b.eq	.LSrcAligned
+	sub	count, count, tmp2
+	/*
+	* process the aligned offset length to make the src aligned firstly.
+	* those extra instructions' cost is acceptable. It also make the
+	* coming accesses are based on aligned address.
+	*/
+	tbz	tmp2, #0, 1f
+	ldrb	tmp1w, [src, #-1]!
+	strb	tmp1w, [dst, #-1]!
+1:
+	tbz	tmp2, #1, 2f
+	ldrh	tmp1w, [src, #-2]!
+	strh	tmp1w, [dst, #-2]!
+2:
+	tbz	tmp2, #2, 3f
+	ldr	tmp1w, [src, #-4]!
+	str	tmp1w, [dst, #-4]!
+3:
+	tbz	tmp2, #3, .LSrcAligned
+	ldr	tmp1, [src, #-8]!
+	str	tmp1, [dst, #-8]!
+
+.LSrcAligned:
+	cmp	count, #64
+	b.ge	.Lcpy_over64
+
+	/*
+	* Deal with small copies quickly by dropping straight into the
+	* exit block.
+	*/
+.Ltail63:
+	/*
+	* Copy up to 48 bytes of data. At this point we only need the
+	* bottom 6 bits of count to be accurate.
+	*/
+	ands	tmp1, count, #0x30
+	b.eq	.Ltail15
+	cmp	tmp1w, #0x20
+	b.eq	1f
+	b.lt	2f
+	ldp	A_l, A_h, [src, #-16]!
+	stp	A_l, A_h, [dst, #-16]!
+1:
+	ldp	A_l, A_h, [src, #-16]!
+	stp	A_l, A_h, [dst, #-16]!
+2:
+	ldp	A_l, A_h, [src, #-16]!
+	stp	A_l, A_h, [dst, #-16]!
+
+.Ltail15:
+	tbz	count, #3, 1f
+	ldr	tmp1, [src, #-8]!
+	str	tmp1, [dst, #-8]!
+1:
+	tbz	count, #2, 2f
+	ldr	tmp1w, [src, #-4]!
+	str	tmp1w, [dst, #-4]!
+2:
+	tbz	count, #1, 3f
+	ldrh	tmp1w, [src, #-2]!
+	strh	tmp1w, [dst, #-2]!
+3:
+	tbz	count, #0, .Lexitfunc
+	ldrb	tmp1w, [src, #-1]
+	strb	tmp1w, [dst, #-1]
+
+.Lexitfunc:
+	ret
+
+.Lcpy_over64:
+	subs	count, count, #128
+	b.ge	.Lcpy_body_large
+	/*
+	* Less than 128 bytes to copy, so handle 64 bytes here and then jump
+	* to the tail.
+	*/
+	ldp	A_l, A_h, [src, #-16]
+	stp	A_l, A_h, [dst, #-16]
+	ldp	B_l, B_h, [src, #-32]
+	ldp	C_l, C_h, [src, #-48]
+	stp	B_l, B_h, [dst, #-32]
+	stp	C_l, C_h, [dst, #-48]
+	ldp	D_l, D_h, [src, #-64]!
+	stp	D_l, D_h, [dst, #-64]!
+
+	tst	count, #0x3f
+	b.ne	.Ltail63
+	ret
+
+	/*
+	* Critical loop. Start at a new cache line boundary. Assuming
+	* 64 bytes per line this ensures the entire loop is in one line.
+	*/
+	.p2align	L1_CACHE_SHIFT
+.Lcpy_body_large:
+	/* pre-load 64 bytes data. */
+	ldp	A_l, A_h, [src, #-16]
+	ldp	B_l, B_h, [src, #-32]
+	ldp	C_l, C_h, [src, #-48]
+	ldp	D_l, D_h, [src, #-64]!
+1:
+	/*
+	* interlace the load of next 64 bytes data block with store of the last
+	* loaded 64 bytes data.
+	*/
+	stp	A_l, A_h, [dst, #-16]
+	ldp	A_l, A_h, [src, #-16]
+	stp	B_l, B_h, [dst, #-32]
+	ldp	B_l, B_h, [src, #-32]
+	stp	C_l, C_h, [dst, #-48]
+	ldp	C_l, C_h, [src, #-48]
+	stp	D_l, D_h, [dst, #-64]!
+	ldp	D_l, D_h, [src, #-64]!
+	subs	count, count, #64
+	b.ge	1b
+	stp	A_l, A_h, [dst, #-16]
+	stp	B_l, B_h, [dst, #-32]
+	stp	C_l, C_h, [dst, #-48]
+	stp	D_l, D_h, [dst, #-64]!
+
+	tst	count, #0x3f
+	b.ne	.Ltail63
+	ret
 ENDPROC(memmove)
diff --git a/arch/arm64/lib/memset.S b/arch/arm64/lib/memset.S
index 87e4a68fbbbc..7c72dfd36b63 100644
--- a/arch/arm64/lib/memset.S
+++ b/arch/arm64/lib/memset.S
@@ -1,5 +1,13 @@
 /*
  * Copyright (C) 2013 ARM Ltd.
+ * Copyright (C) 2013 Linaro.
+ *
+ * This code is based on glibc cortex strings work originally authored by Linaro
+ * and re-licensed under GPLv2 for the Linux kernel. The original code can
+ * be found @
+ *
+ * http://bazaar.launchpad.net/~linaro-toolchain-dev/cortex-strings/trunk/
+ * files/head:/src/aarch64/
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -16,6 +24,7 @@
 
 #include <linux/linkage.h>
 #include <asm/assembler.h>
+#include <asm/cache.h>
 
 /*
  * Fill in the buffer with character c (alignment handled by the hardware)
@@ -27,27 +36,181 @@
  * Returns:
  *	x0 - buf
  */
+
+dstin		.req	x0
+val		.req	w1
+count		.req	x2
+tmp1		.req	x3
+tmp1w		.req	w3
+tmp2		.req	x4
+tmp2w		.req	w4
+zva_len_x	.req	x5
+zva_len		.req	w5
+zva_bits_x	.req	x6
+
+A_l		.req	x7
+A_lw		.req	w7
+dst		.req	x8
+tmp3w		.req	w9
+tmp3		.req	x9
+
 ENTRY(memset)
-	mov	x4, x0
-	and	w1, w1, #0xff
-	orr	w1, w1, w1, lsl #8
-	orr	w1, w1, w1, lsl #16
-	orr	x1, x1, x1, lsl #32
-	subs	x2, x2, #8
-	b.mi	2f
-1:	str	x1, [x4], #8
-	subs	x2, x2, #8
-	b.pl	1b
-2:	adds	x2, x2, #4
-	b.mi	3f
-	sub	x2, x2, #4
-	str	w1, [x4], #4
-3:	adds	x2, x2, #2
-	b.mi	4f
-	sub	x2, x2, #2
-	strh	w1, [x4], #2
-4:	adds	x2, x2, #1
-	b.mi	5f
-	strb	w1, [x4]
-5:	ret
+	mov	dst, dstin	/* Preserve return value.  */
+	and	A_lw, val, #255
+	orr	A_lw, A_lw, A_lw, lsl #8
+	orr	A_lw, A_lw, A_lw, lsl #16
+	orr	A_l, A_l, A_l, lsl #32
+
+	cmp	count, #15
+	b.hi	.Lover16_proc
+	/*All store maybe are non-aligned..*/
+	tbz	count, #3, 1f
+	str	A_l, [dst], #8
+1:
+	tbz	count, #2, 2f
+	str	A_lw, [dst], #4
+2:
+	tbz	count, #1, 3f
+	strh	A_lw, [dst], #2
+3:
+	tbz	count, #0, 4f
+	strb	A_lw, [dst]
+4:
+	ret
+
+.Lover16_proc:
+	/*Whether  the start address is aligned with 16.*/
+	neg	tmp2, dst
+	ands	tmp2, tmp2, #15
+	b.eq	.Laligned
+/*
+* The count is not less than 16, we can use stp to store the start 16 bytes,
+* then adjust the dst aligned with 16.This process will make the current
+* memory address at alignment boundary.
+*/
+	stp	A_l, A_l, [dst] /*non-aligned store..*/
+	/*make the dst aligned..*/
+	sub	count, count, tmp2
+	add	dst, dst, tmp2
+
+.Laligned:
+	cbz	A_l, .Lzero_mem
+
+.Ltail_maybe_long:
+	cmp	count, #64
+	b.ge	.Lnot_short
+.Ltail63:
+	ands	tmp1, count, #0x30
+	b.eq	3f
+	cmp	tmp1w, #0x20
+	b.eq	1f
+	b.lt	2f
+	stp	A_l, A_l, [dst], #16
+1:
+	stp	A_l, A_l, [dst], #16
+2:
+	stp	A_l, A_l, [dst], #16
+/*
+* The last store length is less than 16,use stp to write last 16 bytes.
+* It will lead some bytes written twice and the access is non-aligned.
+*/
+3:
+	ands	count, count, #15
+	cbz	count, 4f
+	add	dst, dst, count
+	stp	A_l, A_l, [dst, #-16]	/* Repeat some/all of last store. */
+4:
+	ret
+
+	/*
+	* Critical loop. Start at a new cache line boundary. Assuming
+	* 64 bytes per line, this ensures the entire loop is in one line.
+	*/
+	.p2align	L1_CACHE_SHIFT
+.Lnot_short:
+	sub	dst, dst, #16/* Pre-bias.  */
+	sub	count, count, #64
+1:
+	stp	A_l, A_l, [dst, #16]
+	stp	A_l, A_l, [dst, #32]
+	stp	A_l, A_l, [dst, #48]
+	stp	A_l, A_l, [dst, #64]!
+	subs	count, count, #64
+	b.ge	1b
+	tst	count, #0x3f
+	add	dst, dst, #16
+	b.ne	.Ltail63
+.Lexitfunc:
+	ret
+
+	/*
+	* For zeroing memory, check to see if we can use the ZVA feature to
+	* zero entire 'cache' lines.
+	*/
+.Lzero_mem:
+	cmp	count, #63
+	b.le	.Ltail63
+	/*
+	* For zeroing small amounts of memory, it's not worth setting up
+	* the line-clear code.
+	*/
+	cmp	count, #128
+	b.lt	.Lnot_short /*count is at least  128 bytes*/
+
+	mrs	tmp1, dczid_el0
+	tbnz	tmp1, #4, .Lnot_short
+	mov	tmp3w, #4
+	and	zva_len, tmp1w, #15	/* Safety: other bits reserved.  */
+	lsl	zva_len, tmp3w, zva_len
+
+	ands	tmp3w, zva_len, #63
+	/*
+	* ensure the zva_len is not less than 64.
+	* It is not meaningful to use ZVA if the block size is less than 64.
+	*/
+	b.ne	.Lnot_short
+.Lzero_by_line:
+	/*
+	* Compute how far we need to go to become suitably aligned. We're
+	* already at quad-word alignment.
+	*/
+	cmp	count, zva_len_x
+	b.lt	.Lnot_short		/* Not enough to reach alignment.  */
+	sub	zva_bits_x, zva_len_x, #1
+	neg	tmp2, dst
+	ands	tmp2, tmp2, zva_bits_x
+	b.eq	2f			/* Already aligned.  */
+	/* Not aligned, check that there's enough to copy after alignment.*/
+	sub	tmp1, count, tmp2
+	/*
+	* grantee the remain length to be ZVA is bigger than 64,
+	* avoid to make the 2f's process over mem range.*/
+	cmp	tmp1, #64
+	ccmp	tmp1, zva_len_x, #8, ge	/* NZCV=0b1000 */
+	b.lt	.Lnot_short
+	/*
+	* We know that there's at least 64 bytes to zero and that it's safe
+	* to overrun by 64 bytes.
+	*/
+	mov	count, tmp1
+1:
+	stp	A_l, A_l, [dst]
+	stp	A_l, A_l, [dst, #16]
+	stp	A_l, A_l, [dst, #32]
+	subs	tmp2, tmp2, #64
+	stp	A_l, A_l, [dst, #48]
+	add	dst, dst, #64
+	b.ge	1b
+	/* We've overrun a bit, so adjust dst downwards.*/
+	add	dst, dst, tmp2
+2:
+	sub	count, count, zva_len_x
+3:
+	dc	zva, dst
+	add	dst, dst, zva_len_x
+	subs	count, count, zva_len_x
+	b.ge	3b
+	ands	count, count, zva_bits_x
+	b.ne	.Ltail_maybe_long
+	ret
 ENDPROC(memset)
diff --git a/arch/arm64/lib/strcmp.S b/arch/arm64/lib/strcmp.S
new file mode 100644
index 000000000000..42f828b06c59
--- /dev/null
+++ b/arch/arm64/lib/strcmp.S
@@ -0,0 +1,234 @@
+/*
+ * Copyright (C) 2013 ARM Ltd.
+ * Copyright (C) 2013 Linaro.
+ *
+ * This code is based on glibc cortex strings work originally authored by Linaro
+ * and re-licensed under GPLv2 for the Linux kernel. The original code can
+ * be found @
+ *
+ * http://bazaar.launchpad.net/~linaro-toolchain-dev/cortex-strings/trunk/
+ * files/head:/src/aarch64/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+/*
+ * compare two strings
+ *
+ * Parameters:
+ *	x0 - const string 1 pointer
+ *    x1 - const string 2 pointer
+ * Returns:
+ * x0 - an integer less than, equal to, or greater than zero
+ * if  s1  is  found, respectively, to be less than, to match,
+ * or be greater than s2.
+ */
+
+#define REP8_01 0x0101010101010101
+#define REP8_7f 0x7f7f7f7f7f7f7f7f
+#define REP8_80 0x8080808080808080
+
+/* Parameters and result.  */
+src1		.req	x0
+src2		.req	x1
+result		.req	x0
+
+/* Internal variables.  */
+data1		.req	x2
+data1w		.req	w2
+data2		.req	x3
+data2w		.req	w3
+has_nul		.req	x4
+diff		.req	x5
+syndrome	.req	x6
+tmp1		.req	x7
+tmp2		.req	x8
+tmp3		.req	x9
+zeroones	.req	x10
+pos		.req	x11
+
+ENTRY(strcmp)
+	eor	tmp1, src1, src2
+	mov	zeroones, #REP8_01
+	tst	tmp1, #7
+	b.ne	.Lmisaligned8
+	ands	tmp1, src1, #7
+	b.ne	.Lmutual_align
+
+	/*
+	* NUL detection works on the principle that (X - 1) & (~X) & 0x80
+	* (=> (X - 1) & ~(X | 0x7f)) is non-zero iff a byte is zero, and
+	* can be done in parallel across the entire word.
+	*/
+.Lloop_aligned:
+	ldr	data1, [src1], #8
+	ldr	data2, [src2], #8
+.Lstart_realigned:
+	sub	tmp1, data1, zeroones
+	orr	tmp2, data1, #REP8_7f
+	eor	diff, data1, data2	/* Non-zero if differences found.  */
+	bic	has_nul, tmp1, tmp2	/* Non-zero if NUL terminator.  */
+	orr	syndrome, diff, has_nul
+	cbz	syndrome, .Lloop_aligned
+	b	.Lcal_cmpresult
+
+.Lmutual_align:
+	/*
+	* Sources are mutually aligned, but are not currently at an
+	* alignment boundary.  Round down the addresses and then mask off
+	* the bytes that preceed the start point.
+	*/
+	bic	src1, src1, #7
+	bic	src2, src2, #7
+	lsl	tmp1, tmp1, #3		/* Bytes beyond alignment -> bits.  */
+	ldr	data1, [src1], #8
+	neg	tmp1, tmp1		/* Bits to alignment -64.  */
+	ldr	data2, [src2], #8
+	mov	tmp2, #~0
+	/* Big-endian.  Early bytes are at MSB.  */
+CPU_BE( lsl	tmp2, tmp2, tmp1 )	/* Shift (tmp1 & 63).  */
+	/* Little-endian.  Early bytes are at LSB.  */
+CPU_LE( lsr	tmp2, tmp2, tmp1 )	/* Shift (tmp1 & 63).  */
+
+	orr	data1, data1, tmp2
+	orr	data2, data2, tmp2
+	b	.Lstart_realigned
+
+.Lmisaligned8:
+	/*
+	* Get the align offset length to compare per byte first.
+	* After this process, one string's address will be aligned.
+	*/
+	and	tmp1, src1, #7
+	neg	tmp1, tmp1
+	add	tmp1, tmp1, #8
+	and	tmp2, src2, #7
+	neg	tmp2, tmp2
+	add	tmp2, tmp2, #8
+	subs	tmp3, tmp1, tmp2
+	csel	pos, tmp1, tmp2, hi /*Choose the maximum. */
+.Ltinycmp:
+	ldrb	data1w, [src1], #1
+	ldrb	data2w, [src2], #1
+	subs	pos, pos, #1
+	ccmp	data1w, #1, #0, ne  /* NZCV = 0b0000.  */
+	ccmp	data1w, data2w, #0, cs  /* NZCV = 0b0000.  */
+	b.eq	.Ltinycmp
+	cbnz	pos, 1f /*find the null or unequal...*/
+	cmp	data1w, #1
+	ccmp	data1w, data2w, #0, cs
+	b.eq	.Lstart_align /*the last bytes are equal....*/
+1:
+	sub	result, data1, data2
+	ret
+
+.Lstart_align:
+	ands	xzr, src1, #7
+	b.eq	.Lrecal_offset
+	/*process more leading bytes to make str1 aligned...*/
+	add	src1, src1, tmp3
+	add	src2, src2, tmp3
+	/*load 8 bytes from aligned str1 and non-aligned str2..*/
+	ldr	data1, [src1], #8
+	ldr	data2, [src2], #8
+
+	sub	tmp1, data1, zeroones
+	orr	tmp2, data1, #REP8_7f
+	bic	has_nul, tmp1, tmp2
+	eor	diff, data1, data2 /* Non-zero if differences found.  */
+	orr	syndrome, diff, has_nul
+	cbnz	syndrome, .Lcal_cmpresult
+	/*How far is the current str2 from the alignment boundary...*/
+	and	tmp3, tmp3, #7
+.Lrecal_offset:
+	neg	pos, tmp3
+.Lloopcmp_proc:
+	/*
+	* Divide the eight bytes into two parts. First,backwards the src2
+	* to an alignment boundary,load eight bytes from the SRC2 alignment
+	* boundary,then compare with the relative bytes from SRC1.
+	* If all 8 bytes are equal,then start the second part's comparison.
+	* Otherwise finish the comparison.
+	* This special handle can garantee all the accesses are in the
+	* thread/task space in avoid to overrange access.
+	*/
+	ldr	data1, [src1,pos]
+	ldr	data2, [src2,pos]
+	sub	tmp1, data1, zeroones
+	orr	tmp2, data1, #REP8_7f
+	bic	has_nul, tmp1, tmp2
+	eor	diff, data1, data2  /* Non-zero if differences found.  */
+	orr	syndrome, diff, has_nul
+	cbnz	syndrome, .Lcal_cmpresult
+
+	/*The second part process*/
+	ldr	data1, [src1], #8
+	ldr	data2, [src2], #8
+	sub	tmp1, data1, zeroones
+	orr	tmp2, data1, #REP8_7f
+	bic	has_nul, tmp1, tmp2
+	eor	diff, data1, data2  /* Non-zero if differences found.  */
+	orr	syndrome, diff, has_nul
+	cbz	syndrome, .Lloopcmp_proc
+
+.Lcal_cmpresult:
+	/*
+	* reversed the byte-order as big-endian,then CLZ can find the most
+	* significant zero bits.
+	*/
+CPU_LE( rev	syndrome, syndrome )
+CPU_LE( rev	data1, data1 )
+CPU_LE( rev	data2, data2 )
+
+	/*
+	* For big-endian we cannot use the trick with the syndrome value
+	* as carry-propagation can corrupt the upper bits if the trailing
+	* bytes in the string contain 0x01.
+	* However, if there is no NUL byte in the dword, we can generate
+	* the result directly.  We ca not just subtract the bytes as the
+	* MSB might be significant.
+	*/
+CPU_BE( cbnz	has_nul, 1f )
+CPU_BE( cmp	data1, data2 )
+CPU_BE( cset	result, ne )
+CPU_BE( cneg	result, result, lo )
+CPU_BE( ret )
+CPU_BE( 1: )
+	/*Re-compute the NUL-byte detection, using a byte-reversed value. */
+CPU_BE(	rev	tmp3, data1 )
+CPU_BE(	sub	tmp1, tmp3, zeroones )
+CPU_BE(	orr	tmp2, tmp3, #REP8_7f )
+CPU_BE(	bic	has_nul, tmp1, tmp2 )
+CPU_BE(	rev	has_nul, has_nul )
+CPU_BE(	orr	syndrome, diff, has_nul )
+
+	clz	pos, syndrome
+	/*
+	* The MS-non-zero bit of the syndrome marks either the first bit
+	* that is different, or the top bit of the first zero byte.
+	* Shifting left now will bring the critical information into the
+	* top bits.
+	*/
+	lsl	data1, data1, pos
+	lsl	data2, data2, pos
+	/*
+	* But we need to zero-extend (char is unsigned) the value and then
+	* perform a signed 32-bit subtraction.
+	*/
+	lsr	data1, data1, #56
+	sub	result, data1, data2, lsr #56
+	ret
+ENDPROC(strcmp)
diff --git a/arch/arm64/lib/strlen.S b/arch/arm64/lib/strlen.S
new file mode 100644
index 000000000000..987b68b9ce44
--- /dev/null
+++ b/arch/arm64/lib/strlen.S
@@ -0,0 +1,126 @@
+/*
+ * Copyright (C) 2013 ARM Ltd.
+ * Copyright (C) 2013 Linaro.
+ *
+ * This code is based on glibc cortex strings work originally authored by Linaro
+ * and re-licensed under GPLv2 for the Linux kernel. The original code can
+ * be found @
+ *
+ * http://bazaar.launchpad.net/~linaro-toolchain-dev/cortex-strings/trunk/
+ * files/head:/src/aarch64/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+/*
+ * calculate the length of a string
+ *
+ * Parameters:
+ *	x0 - const string pointer
+ * Returns:
+ *	x0 - the return length of specific string
+ */
+
+/* Arguments and results.  */
+srcin		.req	x0
+len		.req	x0
+
+/* Locals and temporaries.  */
+src		.req	x1
+data1		.req	x2
+data2		.req	x3
+data2a		.req	x4
+has_nul1	.req	x5
+has_nul2	.req	x6
+tmp1		.req	x7
+tmp2		.req	x8
+tmp3		.req	x9
+tmp4		.req	x10
+zeroones	.req	x11
+pos		.req	x12
+
+#define REP8_01 0x0101010101010101
+#define REP8_7f 0x7f7f7f7f7f7f7f7f
+#define REP8_80 0x8080808080808080
+
+ENTRY(strlen)
+	mov	zeroones, #REP8_01
+	bic	src, srcin, #15
+	ands	tmp1, srcin, #15
+	b.ne	.Lmisaligned
+	/*
+	* NUL detection works on the principle that (X - 1) & (~X) & 0x80
+	* (=> (X - 1) & ~(X | 0x7f)) is non-zero iff a byte is zero, and
+	* can be done in parallel across the entire word.
+	*/
+	/*
+	* The inner loop deals with two Dwords at a time. This has a
+	* slightly higher start-up cost, but we should win quite quickly,
+	* especially on cores with a high number of issue slots per
+	* cycle, as we get much better parallelism out of the operations.
+	*/
+.Lloop:
+	ldp	data1, data2, [src], #16
+.Lrealigned:
+	sub	tmp1, data1, zeroones
+	orr	tmp2, data1, #REP8_7f
+	sub	tmp3, data2, zeroones
+	orr	tmp4, data2, #REP8_7f
+	bic	has_nul1, tmp1, tmp2
+	bics	has_nul2, tmp3, tmp4
+	ccmp	has_nul1, #0, #0, eq	/* NZCV = 0000  */
+	b.eq	.Lloop
+
+	sub	len, src, srcin
+	cbz	has_nul1, .Lnul_in_data2
+CPU_BE(	mov	data2, data1 )	/*prepare data to re-calculate the syndrome*/
+	sub	len, len, #8
+	mov	has_nul2, has_nul1
+.Lnul_in_data2:
+	/*
+	* For big-endian, carry propagation (if the final byte in the
+	* string is 0x01) means we cannot use has_nul directly.  The
+	* easiest way to get the correct byte is to byte-swap the data
+	* and calculate the syndrome a second time.
+	*/
+CPU_BE( rev	data2, data2 )
+CPU_BE( sub	tmp1, data2, zeroones )
+CPU_BE( orr	tmp2, data2, #REP8_7f )
+CPU_BE( bic	has_nul2, tmp1, tmp2 )
+
+	sub	len, len, #8
+	rev	has_nul2, has_nul2
+	clz	pos, has_nul2
+	add	len, len, pos, lsr #3		/* Bits to bytes.  */
+	ret
+
+.Lmisaligned:
+	cmp	tmp1, #8
+	neg	tmp1, tmp1
+	ldp	data1, data2, [src], #16
+	lsl	tmp1, tmp1, #3		/* Bytes beyond alignment -> bits.  */
+	mov	tmp2, #~0
+	/* Big-endian.  Early bytes are at MSB.  */
+CPU_BE( lsl	tmp2, tmp2, tmp1 )	/* Shift (tmp1 & 63).  */
+	/* Little-endian.  Early bytes are at LSB.  */
+CPU_LE( lsr	tmp2, tmp2, tmp1 )	/* Shift (tmp1 & 63).  */
+
+	orr	data1, data1, tmp2
+	orr	data2a, data2, tmp2
+	csinv	data1, data1, xzr, le
+	csel	data2, data2, data2a, le
+	b	.Lrealigned
+ENDPROC(strlen)
diff --git a/arch/arm64/lib/strncmp.S b/arch/arm64/lib/strncmp.S
new file mode 100644
index 000000000000..0224cf5a5533
--- /dev/null
+++ b/arch/arm64/lib/strncmp.S
@@ -0,0 +1,310 @@
+/*
+ * Copyright (C) 2013 ARM Ltd.
+ * Copyright (C) 2013 Linaro.
+ *
+ * This code is based on glibc cortex strings work originally authored by Linaro
+ * and re-licensed under GPLv2 for the Linux kernel. The original code can
+ * be found @
+ *
+ * http://bazaar.launchpad.net/~linaro-toolchain-dev/cortex-strings/trunk/
+ * files/head:/src/aarch64/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+/*
+ * compare two strings
+ *
+ * Parameters:
+ *  x0 - const string 1 pointer
+ *  x1 - const string 2 pointer
+ *  x2 - the maximal length to be compared
+ * Returns:
+ *  x0 - an integer less than, equal to, or greater than zero if s1 is found,
+ *     respectively, to be less than, to match, or be greater than s2.
+ */
+
+#define REP8_01 0x0101010101010101
+#define REP8_7f 0x7f7f7f7f7f7f7f7f
+#define REP8_80 0x8080808080808080
+
+/* Parameters and result.  */
+src1		.req	x0
+src2		.req	x1
+limit		.req	x2
+result		.req	x0
+
+/* Internal variables.  */
+data1		.req	x3
+data1w		.req	w3
+data2		.req	x4
+data2w		.req	w4
+has_nul		.req	x5
+diff		.req	x6
+syndrome	.req	x7
+tmp1		.req	x8
+tmp2		.req	x9
+tmp3		.req	x10
+zeroones	.req	x11
+pos		.req	x12
+limit_wd	.req	x13
+mask		.req	x14
+endloop		.req	x15
+
+ENTRY(strncmp)
+	cbz	limit, .Lret0
+	eor	tmp1, src1, src2
+	mov	zeroones, #REP8_01
+	tst	tmp1, #7
+	b.ne	.Lmisaligned8
+	ands	tmp1, src1, #7
+	b.ne	.Lmutual_align
+	/* Calculate the number of full and partial words -1.  */
+	/*
+	* when limit is mulitply of 8, if not sub 1,
+	* the judgement of last dword will wrong.
+	*/
+	sub	limit_wd, limit, #1 /* limit != 0, so no underflow.  */
+	lsr	limit_wd, limit_wd, #3  /* Convert to Dwords.  */
+
+	/*
+	* NUL detection works on the principle that (X - 1) & (~X) & 0x80
+	* (=> (X - 1) & ~(X | 0x7f)) is non-zero iff a byte is zero, and
+	* can be done in parallel across the entire word.
+	*/
+.Lloop_aligned:
+	ldr	data1, [src1], #8
+	ldr	data2, [src2], #8
+.Lstart_realigned:
+	subs	limit_wd, limit_wd, #1
+	sub	tmp1, data1, zeroones
+	orr	tmp2, data1, #REP8_7f
+	eor	diff, data1, data2  /* Non-zero if differences found.  */
+	csinv	endloop, diff, xzr, pl  /* Last Dword or differences.*/
+	bics	has_nul, tmp1, tmp2 /* Non-zero if NUL terminator.  */
+	ccmp	endloop, #0, #0, eq
+	b.eq	.Lloop_aligned
+
+	/*Not reached the limit, must have found the end or a diff.  */
+	tbz	limit_wd, #63, .Lnot_limit
+
+	/* Limit % 8 == 0 => all bytes significant.  */
+	ands	limit, limit, #7
+	b.eq	.Lnot_limit
+
+	lsl	limit, limit, #3    /* Bits -> bytes.  */
+	mov	mask, #~0
+CPU_BE( lsr	mask, mask, limit )
+CPU_LE( lsl	mask, mask, limit )
+	bic	data1, data1, mask
+	bic	data2, data2, mask
+
+	/* Make sure that the NUL byte is marked in the syndrome.  */
+	orr	has_nul, has_nul, mask
+
+.Lnot_limit:
+	orr	syndrome, diff, has_nul
+	b	.Lcal_cmpresult
+
+.Lmutual_align:
+	/*
+	* Sources are mutually aligned, but are not currently at an
+	* alignment boundary.  Round down the addresses and then mask off
+	* the bytes that precede the start point.
+	* We also need to adjust the limit calculations, but without
+	* overflowing if the limit is near ULONG_MAX.
+	*/
+	bic	src1, src1, #7
+	bic	src2, src2, #7
+	ldr	data1, [src1], #8
+	neg	tmp3, tmp1, lsl #3  /* 64 - bits(bytes beyond align). */
+	ldr	data2, [src2], #8
+	mov	tmp2, #~0
+	sub	limit_wd, limit, #1 /* limit != 0, so no underflow.  */
+	/* Big-endian.  Early bytes are at MSB.  */
+CPU_BE( lsl	tmp2, tmp2, tmp3 )	/* Shift (tmp1 & 63).  */
+	/* Little-endian.  Early bytes are at LSB.  */
+CPU_LE( lsr	tmp2, tmp2, tmp3 )	/* Shift (tmp1 & 63).  */
+
+	and	tmp3, limit_wd, #7
+	lsr	limit_wd, limit_wd, #3
+	/* Adjust the limit. Only low 3 bits used, so overflow irrelevant.*/
+	add	limit, limit, tmp1
+	add	tmp3, tmp3, tmp1
+	orr	data1, data1, tmp2
+	orr	data2, data2, tmp2
+	add	limit_wd, limit_wd, tmp3, lsr #3
+	b	.Lstart_realigned
+
+/*when src1 offset is not equal to src2 offset...*/
+.Lmisaligned8:
+	cmp	limit, #8
+	b.lo	.Ltiny8proc /*limit < 8... */
+	/*
+	* Get the align offset length to compare per byte first.
+	* After this process, one string's address will be aligned.*/
+	and	tmp1, src1, #7
+	neg	tmp1, tmp1
+	add	tmp1, tmp1, #8
+	and	tmp2, src2, #7
+	neg	tmp2, tmp2
+	add	tmp2, tmp2, #8
+	subs	tmp3, tmp1, tmp2
+	csel	pos, tmp1, tmp2, hi /*Choose the maximum. */
+	/*
+	* Here, limit is not less than 8, so directly run .Ltinycmp
+	* without checking the limit.*/
+	sub	limit, limit, pos
+.Ltinycmp:
+	ldrb	data1w, [src1], #1
+	ldrb	data2w, [src2], #1
+	subs	pos, pos, #1
+	ccmp	data1w, #1, #0, ne  /* NZCV = 0b0000.  */
+	ccmp	data1w, data2w, #0, cs  /* NZCV = 0b0000.  */
+	b.eq	.Ltinycmp
+	cbnz	pos, 1f /*find the null or unequal...*/
+	cmp	data1w, #1
+	ccmp	data1w, data2w, #0, cs
+	b.eq	.Lstart_align /*the last bytes are equal....*/
+1:
+	sub	result, data1, data2
+	ret
+
+.Lstart_align:
+	lsr	limit_wd, limit, #3
+	cbz	limit_wd, .Lremain8
+	/*process more leading bytes to make str1 aligned...*/
+	ands	xzr, src1, #7
+	b.eq	.Lrecal_offset
+	add	src1, src1, tmp3	/*tmp3 is positive in this branch.*/
+	add	src2, src2, tmp3
+	ldr	data1, [src1], #8
+	ldr	data2, [src2], #8
+
+	sub	limit, limit, tmp3
+	lsr	limit_wd, limit, #3
+	subs	limit_wd, limit_wd, #1
+
+	sub	tmp1, data1, zeroones
+	orr	tmp2, data1, #REP8_7f
+	eor	diff, data1, data2  /* Non-zero if differences found.  */
+	csinv	endloop, diff, xzr, ne/*if limit_wd is 0,will finish the cmp*/
+	bics	has_nul, tmp1, tmp2
+	ccmp	endloop, #0, #0, eq /*has_null is ZERO: no null byte*/
+	b.ne	.Lunequal_proc
+	/*How far is the current str2 from the alignment boundary...*/
+	and	tmp3, tmp3, #7
+.Lrecal_offset:
+	neg	pos, tmp3
+.Lloopcmp_proc:
+	/*
+	* Divide the eight bytes into two parts. First,backwards the src2
+	* to an alignment boundary,load eight bytes from the SRC2 alignment
+	* boundary,then compare with the relative bytes from SRC1.
+	* If all 8 bytes are equal,then start the second part's comparison.
+	* Otherwise finish the comparison.
+	* This special handle can garantee all the accesses are in the
+	* thread/task space in avoid to overrange access.
+	*/
+	ldr	data1, [src1,pos]
+	ldr	data2, [src2,pos]
+	sub	tmp1, data1, zeroones
+	orr	tmp2, data1, #REP8_7f
+	bics	has_nul, tmp1, tmp2 /* Non-zero if NUL terminator.  */
+	eor	diff, data1, data2  /* Non-zero if differences found.  */
+	csinv	endloop, diff, xzr, eq
+	cbnz	endloop, .Lunequal_proc
+
+	/*The second part process*/
+	ldr	data1, [src1], #8
+	ldr	data2, [src2], #8
+	subs	limit_wd, limit_wd, #1
+	sub	tmp1, data1, zeroones
+	orr	tmp2, data1, #REP8_7f
+	eor	diff, data1, data2  /* Non-zero if differences found.  */
+	csinv	endloop, diff, xzr, ne/*if limit_wd is 0,will finish the cmp*/
+	bics	has_nul, tmp1, tmp2
+	ccmp	endloop, #0, #0, eq /*has_null is ZERO: no null byte*/
+	b.eq	.Lloopcmp_proc
+
+.Lunequal_proc:
+	orr	syndrome, diff, has_nul
+	cbz	syndrome, .Lremain8
+.Lcal_cmpresult:
+	/*
+	* reversed the byte-order as big-endian,then CLZ can find the most
+	* significant zero bits.
+	*/
+CPU_LE( rev	syndrome, syndrome )
+CPU_LE( rev	data1, data1 )
+CPU_LE( rev	data2, data2 )
+	/*
+	* For big-endian we cannot use the trick with the syndrome value
+	* as carry-propagation can corrupt the upper bits if the trailing
+	* bytes in the string contain 0x01.
+	* However, if there is no NUL byte in the dword, we can generate
+	* the result directly.  We can't just subtract the bytes as the
+	* MSB might be significant.
+	*/
+CPU_BE( cbnz	has_nul, 1f )
+CPU_BE( cmp	data1, data2 )
+CPU_BE( cset	result, ne )
+CPU_BE( cneg	result, result, lo )
+CPU_BE( ret )
+CPU_BE( 1: )
+	/* Re-compute the NUL-byte detection, using a byte-reversed value.*/
+CPU_BE( rev	tmp3, data1 )
+CPU_BE( sub	tmp1, tmp3, zeroones )
+CPU_BE( orr	tmp2, tmp3, #REP8_7f )
+CPU_BE( bic	has_nul, tmp1, tmp2 )
+CPU_BE( rev	has_nul, has_nul )
+CPU_BE( orr	syndrome, diff, has_nul )
+	/*
+	* The MS-non-zero bit of the syndrome marks either the first bit
+	* that is different, or the top bit of the first zero byte.
+	* Shifting left now will bring the critical information into the
+	* top bits.
+	*/
+	clz	pos, syndrome
+	lsl	data1, data1, pos
+	lsl	data2, data2, pos
+	/*
+	* But we need to zero-extend (char is unsigned) the value and then
+	* perform a signed 32-bit subtraction.
+	*/
+	lsr	data1, data1, #56
+	sub	result, data1, data2, lsr #56
+	ret
+
+.Lremain8:
+	/* Limit % 8 == 0 => all bytes significant.  */
+	ands	limit, limit, #7
+	b.eq	.Lret0
+.Ltiny8proc:
+	ldrb	data1w, [src1], #1
+	ldrb	data2w, [src2], #1
+	subs	limit, limit, #1
+
+	ccmp	data1w, #1, #0, ne  /* NZCV = 0b0000.  */
+	ccmp	data1w, data2w, #0, cs  /* NZCV = 0b0000.  */
+	b.eq	.Ltiny8proc
+	sub	result, data1, data2
+	ret
+
+.Lret0:
+	mov	result, #0
+	ret
+ENDPROC(strncmp)
diff --git a/arch/arm64/lib/strnlen.S b/arch/arm64/lib/strnlen.S
new file mode 100644
index 000000000000..2ca665711bf2
--- /dev/null
+++ b/arch/arm64/lib/strnlen.S
@@ -0,0 +1,171 @@
+/*
+ * Copyright (C) 2013 ARM Ltd.
+ * Copyright (C) 2013 Linaro.
+ *
+ * This code is based on glibc cortex strings work originally authored by Linaro
+ * and re-licensed under GPLv2 for the Linux kernel. The original code can
+ * be found @
+ *
+ * http://bazaar.launchpad.net/~linaro-toolchain-dev/cortex-strings/trunk/
+ * files/head:/src/aarch64/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+/*
+ * determine the length of a fixed-size string
+ *
+ * Parameters:
+ *	x0 - const string pointer
+ *	x1 - maximal string length
+ * Returns:
+ *	x0 - the return length of specific string
+ */
+
+/* Arguments and results.  */
+srcin		.req	x0
+len		.req	x0
+limit		.req	x1
+
+/* Locals and temporaries.  */
+src		.req	x2
+data1		.req	x3
+data2		.req	x4
+data2a		.req	x5
+has_nul1	.req	x6
+has_nul2	.req	x7
+tmp1		.req	x8
+tmp2		.req	x9
+tmp3		.req	x10
+tmp4		.req	x11
+zeroones	.req	x12
+pos		.req	x13
+limit_wd	.req	x14
+
+#define REP8_01 0x0101010101010101
+#define REP8_7f 0x7f7f7f7f7f7f7f7f
+#define REP8_80 0x8080808080808080
+
+ENTRY(strnlen)
+	cbz	limit, .Lhit_limit
+	mov	zeroones, #REP8_01
+	bic	src, srcin, #15
+	ands	tmp1, srcin, #15
+	b.ne	.Lmisaligned
+	/* Calculate the number of full and partial words -1.  */
+	sub	limit_wd, limit, #1 /* Limit != 0, so no underflow.  */
+	lsr	limit_wd, limit_wd, #4  /* Convert to Qwords.  */
+
+	/*
+	* NUL detection works on the principle that (X - 1) & (~X) & 0x80
+	* (=> (X - 1) & ~(X | 0x7f)) is non-zero iff a byte is zero, and
+	* can be done in parallel across the entire word.
+	*/
+	/*
+	* The inner loop deals with two Dwords at a time.  This has a
+	* slightly higher start-up cost, but we should win quite quickly,
+	* especially on cores with a high number of issue slots per
+	* cycle, as we get much better parallelism out of the operations.
+	*/
+.Lloop:
+	ldp	data1, data2, [src], #16
+.Lrealigned:
+	sub	tmp1, data1, zeroones
+	orr	tmp2, data1, #REP8_7f
+	sub	tmp3, data2, zeroones
+	orr	tmp4, data2, #REP8_7f
+	bic	has_nul1, tmp1, tmp2
+	bic	has_nul2, tmp3, tmp4
+	subs	limit_wd, limit_wd, #1
+	orr	tmp1, has_nul1, has_nul2
+	ccmp	tmp1, #0, #0, pl    /* NZCV = 0000  */
+	b.eq	.Lloop
+
+	cbz	tmp1, .Lhit_limit   /* No null in final Qword.  */
+
+	/*
+	* We know there's a null in the final Qword. The easiest thing
+	* to do now is work out the length of the string and return
+	* MIN (len, limit).
+	*/
+	sub	len, src, srcin
+	cbz	has_nul1, .Lnul_in_data2
+CPU_BE( mov	data2, data1 )	/*perpare data to re-calculate the syndrome*/
+
+	sub	len, len, #8
+	mov	has_nul2, has_nul1
+.Lnul_in_data2:
+	/*
+	* For big-endian, carry propagation (if the final byte in the
+	* string is 0x01) means we cannot use has_nul directly.  The
+	* easiest way to get the correct byte is to byte-swap the data
+	* and calculate the syndrome a second time.
+	*/
+CPU_BE( rev	data2, data2 )
+CPU_BE( sub	tmp1, data2, zeroones )
+CPU_BE( orr	tmp2, data2, #REP8_7f )
+CPU_BE( bic	has_nul2, tmp1, tmp2 )
+
+	sub	len, len, #8
+	rev	has_nul2, has_nul2
+	clz	pos, has_nul2
+	add	len, len, pos, lsr #3       /* Bits to bytes.  */
+	cmp	len, limit
+	csel	len, len, limit, ls     /* Return the lower value.  */
+	ret
+
+.Lmisaligned:
+	/*
+	* Deal with a partial first word.
+	* We're doing two things in parallel here;
+	* 1) Calculate the number of words (but avoiding overflow if
+	* limit is near ULONG_MAX) - to do this we need to work out
+	* limit + tmp1 - 1 as a 65-bit value before shifting it;
+	* 2) Load and mask the initial data words - we force the bytes
+	* before the ones we are interested in to 0xff - this ensures
+	* early bytes will not hit any zero detection.
+	*/
+	ldp	data1, data2, [src], #16
+
+	sub	limit_wd, limit, #1
+	and	tmp3, limit_wd, #15
+	lsr	limit_wd, limit_wd, #4
+
+	add	tmp3, tmp3, tmp1
+	add	limit_wd, limit_wd, tmp3, lsr #4
+
+	neg	tmp4, tmp1
+	lsl	tmp4, tmp4, #3  /* Bytes beyond alignment -> bits.  */
+
+	mov	tmp2, #~0
+	/* Big-endian.  Early bytes are at MSB.  */
+CPU_BE( lsl	tmp2, tmp2, tmp4 )	/* Shift (tmp1 & 63).  */
+	/* Little-endian.  Early bytes are at LSB.  */
+CPU_LE( lsr	tmp2, tmp2, tmp4 )	/* Shift (tmp1 & 63).  */
+
+	cmp	tmp1, #8
+
+	orr	data1, data1, tmp2
+	orr	data2a, data2, tmp2
+
+	csinv	data1, data1, xzr, le
+	csel	data2, data2, data2a, le
+	b	.Lrealigned
+
+.Lhit_limit:
+	mov	len, limit
+	ret
+ENDPROC(strnlen)