diff options
author | Haavard Skinnemoen <hskinnemoen@atmel.com> | 2006-09-25 23:32:13 -0700 |
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committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-09-26 08:48:54 -0700 |
commit | 5f97f7f9400de47ae837170bb274e90ad3934386 (patch) | |
tree | 514451e6dc6b46253293a00035d375e77b1c65ed /arch/avr32/boot/u-boot/head.S | |
parent | 53e62d3aaa60590d4a69b4e07c29f448b5151047 (diff) | |
download | blackbird-op-linux-5f97f7f9400de47ae837170bb274e90ad3934386.tar.gz blackbird-op-linux-5f97f7f9400de47ae837170bb274e90ad3934386.zip |
[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/boot/u-boot/head.S')
-rw-r--r-- | arch/avr32/boot/u-boot/head.S | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/arch/avr32/boot/u-boot/head.S b/arch/avr32/boot/u-boot/head.S new file mode 100644 index 000000000000..4488fa27fe94 --- /dev/null +++ b/arch/avr32/boot/u-boot/head.S @@ -0,0 +1,60 @@ +/* + * Startup code for use with the u-boot bootloader. + * + * Copyright (C) 2004-2006 Atmel Corporation + * + * 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. + */ +#include <asm/setup.h> + + /* + * The kernel is loaded where we want it to be and all caches + * have just been flushed. We get two parameters from u-boot: + * + * r12 contains a magic number (ATAG_MAGIC) + * r11 points to a tag table providing information about + * the system. + */ + .section .init.text,"ax" + .global _start +_start: + /* Check if the boot loader actually provided a tag table */ + lddpc r0, magic_number + cp.w r12, r0 + brne no_tag_table + + /* Initialize .bss */ + lddpc r2, bss_start_addr + lddpc r3, end_addr + mov r0, 0 + mov r1, 0 +1: st.d r2++, r0 + cp r2, r3 + brlo 1b + + /* + * Save the tag table address for later use. This must be done + * _after_ .bss has been initialized... + */ + lddpc r0, tag_table_addr + st.w r0[0], r11 + + /* Jump to loader-independent setup code */ + rjmp kernel_entry + + .align 2 +magic_number: + .long ATAG_MAGIC +tag_table_addr: + .long bootloader_tags +bss_start_addr: + .long __bss_start +end_addr: + .long _end + +no_tag_table: + sub r12, pc, (. - 2f) + bral panic +2: .asciz "Boot loader didn't provide correct magic number\n" |