arm64: klib: Optimised memory functions

This patch introduces AArch64-specific memory functions (memcpy,
memmove, memchr, memset). These functions are not optimised for any CPU
implementation but can be used as a starting point once hardware is
available.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Catalin Marinas 2013-03-21 16:16:43 +00:00
parent 792072066d
commit 4a8992271c
8 changed files with 246 additions and 2 deletions

View file

@ -39,7 +39,6 @@ generic-y += shmbuf.h
generic-y += sizes.h generic-y += sizes.h
generic-y += socket.h generic-y += socket.h
generic-y += sockios.h generic-y += sockios.h
generic-y += string.h
generic-y += switch_to.h generic-y += switch_to.h
generic-y += swab.h generic-y += swab.h
generic-y += termbits.h generic-y += termbits.h

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@ -0,0 +1,31 @@
/*
* Copyright (C) 2013 ARM Ltd.
*
* 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/>.
*/
#ifndef __ASM_STRING_H
#define __ASM_STRING_H
#define __HAVE_ARCH_MEMCPY
extern void *memcpy(void *, const void *, __kernel_size_t);
#define __HAVE_ARCH_MEMMOVE
extern void *memmove(void *, const void *, __kernel_size_t);
#define __HAVE_ARCH_MEMCHR
extern void *memchr(const void *, int, __kernel_size_t);
#define __HAVE_ARCH_MEMSET
extern void *memset(void *, int, __kernel_size_t);
#endif

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@ -46,3 +46,9 @@ EXPORT_SYMBOL(__atomic_hash);
/* physical memory */ /* physical memory */
EXPORT_SYMBOL(memstart_addr); EXPORT_SYMBOL(memstart_addr);
/* string / mem functions */
EXPORT_SYMBOL(memset);
EXPORT_SYMBOL(memcpy);
EXPORT_SYMBOL(memmove);
EXPORT_SYMBOL(memchr);

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@ -1,4 +1,5 @@
lib-y := bitops.o delay.o \ lib-y := bitops.o delay.o \
strncpy_from_user.o strnlen_user.o clear_user.o \ strncpy_from_user.o strnlen_user.o clear_user.o \
copy_from_user.o copy_to_user.o copy_in_user.o \ copy_from_user.o copy_to_user.o copy_in_user.o \
copy_page.o clear_page.o copy_page.o clear_page.o \
memchr.o memcpy.o memmove.o memset.o

44
arch/arm64/lib/memchr.S Normal file
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@ -0,0 +1,44 @@
/*
* Based on arch/arm/lib/memchr.S
*
* Copyright (C) 1995-2000 Russell King
* Copyright (C) 2013 ARM Ltd.
*
* 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>
/*
* Find a character in an area of memory.
*
* Parameters:
* x0 - buf
* x1 - c
* x2 - n
* Returns:
* x0 - address of first occurrence of 'c' or 0
*/
ENTRY(memchr)
and w1, w1, #0xff
1: subs x2, x2, #1
b.mi 2f
ldrb w3, [x0], #1
cmp w3, w1
b.ne 1b
sub x0, x0, #1
ret
2: mov x0, #0
ret
ENDPROC(memchr)

53
arch/arm64/lib/memcpy.S Normal file
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@ -0,0 +1,53 @@
/*
* Copyright (C) 2013 ARM Ltd.
*
* 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>
/*
* Copy a buffer from src to dest (alignment handled by the hardware)
*
* Parameters:
* x0 - dest
* x1 - src
* x2 - n
* Returns:
* x0 - dest
*/
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
ENDPROC(memcpy)

57
arch/arm64/lib/memmove.S Normal file
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@ -0,0 +1,57 @@
/*
* Copyright (C) 2013 ARM Ltd.
*
* 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>
/*
* Move a buffer from src to test (alignment handled by the hardware).
* If dest <= src, call memcpy, otherwise copy in reverse order.
*
* Parameters:
* x0 - dest
* x1 - src
* x2 - n
* Returns:
* x0 - dest
*/
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
ENDPROC(memmove)

53
arch/arm64/lib/memset.S Normal file
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@ -0,0 +1,53 @@
/*
* Copyright (C) 2013 ARM Ltd.
*
* 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>
/*
* Fill in the buffer with character c (alignment handled by the hardware)
*
* Parameters:
* x0 - buf
* x1 - c
* x2 - n
* Returns:
* x0 - buf
*/
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
ENDPROC(memset)