[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>

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"