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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/delay.c
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/delay.c')
-rw-r--r--arch/avr32/lib/delay.c55
1 files changed, 55 insertions, 0 deletions
diff --git a/arch/avr32/lib/delay.c b/arch/avr32/lib/delay.c
new file mode 100644
index 000000000000..462c8307b680
--- /dev/null
+++ b/arch/avr32/lib/delay.c
@@ -0,0 +1,55 @@
+/*
+ * Precise Delay Loops for avr32
+ *
+ * Copyright (C) 1993 Linus Torvalds
+ * Copyright (C) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
+ * Copyright (C) 2005-2006 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 <linux/delay.h>
+#include <linux/module.h>
+#include <linux/types.h>
+
+#include <asm/delay.h>
+#include <asm/processor.h>
+#include <asm/sysreg.h>
+
+int read_current_timer(unsigned long *timer_value)
+{
+ *timer_value = sysreg_read(COUNT);
+ return 0;
+}
+
+void __delay(unsigned long loops)
+{
+ unsigned bclock, now;
+
+ bclock = sysreg_read(COUNT);
+ do {
+ now = sysreg_read(COUNT);
+ } while ((now - bclock) < loops);
+}
+
+inline void __const_udelay(unsigned long xloops)
+{
+ unsigned long long loops;
+
+ asm("mulu.d %0, %1, %2"
+ : "=r"(loops)
+ : "r"(current_cpu_data.loops_per_jiffy * HZ), "r"(xloops));
+ __delay(loops >> 32);
+}
+
+void __udelay(unsigned long usecs)
+{
+ __const_udelay(usecs * 0x000010c7); /* 2**32 / 1000000 (rounded up) */
+}
+
+void __ndelay(unsigned long nsecs)
+{
+ __const_udelay(nsecs * 0x00005); /* 2**32 / 1000000000 (rounded up) */
+}