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authorHaavard Skinnemoen <hskinnemoen@atmel.com>2006-09-26 10:32:13 +0400
committerLinus Torvalds <torvalds@g5.osdl.org>2006-09-26 19:48:54 +0400
commit5f97f7f9400de47ae837170bb274e90ad3934386 (patch)
tree514451e6dc6b46253293a00035d375e77b1c65ed /arch/avr32/lib/memset.S
parent53e62d3aaa60590d4a69b4e07c29f448b5151047 (diff)
downloadlinux-5f97f7f9400de47ae837170bb274e90ad3934386.tar.xz
[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>
Diffstat (limited to 'arch/avr32/lib/memset.S')
-rw-r--r--arch/avr32/lib/memset.S72
1 files changed, 72 insertions, 0 deletions
diff --git a/arch/avr32/lib/memset.S b/arch/avr32/lib/memset.S
new file mode 100644
index 000000000000..40da32c0480c
--- /dev/null
+++ b/arch/avr32/lib/memset.S
@@ -0,0 +1,72 @@
+/*
+ * 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