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linux-next/arch/avr32/lib/memset.S
Haavard Skinnemoen 5f97f7f940 [PATCH] avr32 architecture
This adds support for the Atmel AVR32 architecture as well as the AT32AP7000
CPU and the AT32STK1000 development board.

AVR32 is a new high-performance 32-bit RISC microprocessor core, designed for
cost-sensitive embedded applications, with particular emphasis on low power
consumption and high code density.  The AVR32 architecture is not binary
compatible with earlier 8-bit AVR architectures.

The AVR32 architecture, including the instruction set, is described by the
AVR32 Architecture Manual, available from

http://www.atmel.com/dyn/resources/prod_documents/doc32000.pdf

The Atmel AT32AP7000 is the first CPU implementing the AVR32 architecture.  It
features a 7-stage pipeline, 16KB instruction and data caches and a full
Memory Management Unit.  It also comes with a large set of integrated
peripherals, many of which are shared with the AT91 ARM-based controllers from
Atmel.

Full data sheet is available from

http://www.atmel.com/dyn/resources/prod_documents/doc32003.pdf

while the CPU core implementation including caches and MMU is documented by
the AVR32 AP Technical Reference, available from

http://www.atmel.com/dyn/resources/prod_documents/doc32001.pdf

Information about the AT32STK1000 development board can be found at

http://www.atmel.com/dyn/products/tools_card.asp?tool_id=3918

including a BSP CD image with an earlier version of this patch, development
tools (binaries and source/patches) and a root filesystem image suitable for
booting from SD card.

Alternatively, there's a preliminary "getting started" guide available at
http://avr32linux.org/twiki/bin/view/Main/GettingStarted which provides links
to the sources and patches you will need in order to set up a cross-compiling
environment for avr32-linux.

This patch, as well as the other patches included with the BSP and the
toolchain patches, is actively supported by Atmel Corporation.

[dmccr@us.ibm.com: Fix more pxx_page macro locations]
[bunk@stusta.de: fix `make defconfig']
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Dave McCracken <dmccr@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:54 -07:00

73 lines
1.2 KiB
ArmAsm

/*
* Copyright (C) 2004-2006 Atmel Corporation
*
* Based on linux/arch/arm/lib/memset.S
* Copyright (C) 1995-2000 Russell King
*
* 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.
*
* ASM optimised string functions
*/
#include <asm/asm.h>
/*
* r12: void *b
* r11: int c
* r10: size_t len
*
* Returns b in r12
*/
.text
.global memset
.type memset, @function
.align 5
memset:
mov r9, r12
mov r8, r12
or r11, r11, r11 << 8
andl r9, 3, COH
brne 1f
2: or r11, r11, r11 << 16
sub r10, 4
brlt 5f
/* Let's do some real work */
4: st.w r8++, r11
sub r10, 4
brge 4b
/*
* When we get here, we've got less than 4 bytes to set. r10
* might be negative.
*/
5: sub r10, -4
reteq r12
/* Fastpath ends here, exactly 32 bytes from memset */
/* Handle unaligned count or pointer */
bld r10, 1
brcc 6f
st.b r8++, r11
st.b r8++, r11
bld r10, 0
retcc r12
6: st.b r8++, r11
retal r12
/* Handle unaligned pointer */
1: sub r10, 4
brlt 5b
add r10, r9
lsl r9, 1
add pc, r9
st.b r8++, r11
st.b r8++, r11
st.b r8++, r11
rjmp 2b
.size memset, . - memset