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authorHaavard Skinnemoen <hskinnemoen@atmel.com>2006-09-25 23:32:13 -0700
committerLinus Torvalds <torvalds@g5.osdl.org>2006-09-26 08:48:54 -0700
commit5f97f7f9400de47ae837170bb274e90ad3934386 (patch)
tree514451e6dc6b46253293a00035d375e77b1c65ed /arch/avr32/lib/findbit.S
parent53e62d3aaa60590d4a69b4e07c29f448b5151047 (diff)
downloadblackbird-op-linux-5f97f7f9400de47ae837170bb274e90ad3934386.tar.gz
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[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/findbit.S')
-rw-r--r--arch/avr32/lib/findbit.S154
1 files changed, 154 insertions, 0 deletions
diff --git a/arch/avr32/lib/findbit.S b/arch/avr32/lib/findbit.S
new file mode 100644
index 000000000000..2b4856f4bf7c
--- /dev/null
+++ b/arch/avr32/lib/findbit.S
@@ -0,0 +1,154 @@
+/*
+ * Copyright (C) 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/linkage.h>
+
+ .text
+ /*
+ * unsigned long find_first_zero_bit(const unsigned long *addr,
+ * unsigned long size)
+ */
+ENTRY(find_first_zero_bit)
+ cp.w r11, 0
+ reteq r11
+ mov r9, r11
+1: ld.w r8, r12[0]
+ com r8
+ brne .L_found
+ sub r12, -4
+ sub r9, 32
+ brgt 1b
+ retal r11
+
+ /*
+ * unsigned long find_next_zero_bit(const unsigned long *addr,
+ * unsigned long size,
+ * unsigned long offset)
+ */
+ENTRY(find_next_zero_bit)
+ lsr r8, r10, 5
+ sub r9, r11, r10
+ retle r11
+
+ lsl r8, 2
+ add r12, r8
+ andl r10, 31, COH
+ breq 1f
+
+ /* offset is not word-aligned. Handle the first (32 - r10) bits */
+ ld.w r8, r12[0]
+ com r8
+ sub r12, -4
+ lsr r8, r8, r10
+ brne .L_found
+
+ /* r9 = r9 - (32 - r10) = r9 + r10 - 32 */
+ add r9, r10
+ sub r9, 32
+ retle r11
+
+ /* Main loop. offset must be word-aligned */
+1: ld.w r8, r12[0]
+ com r8
+ brne .L_found
+ sub r12, -4
+ sub r9, 32
+ brgt 1b
+ retal r11
+
+ /* Common return path for when a bit is actually found. */
+.L_found:
+ brev r8
+ clz r10, r8
+ rsub r9, r11
+ add r10, r9
+
+ /* XXX: If we don't have to return exactly "size" when the bit
+ is not found, we may drop this "min" thing */
+ min r12, r11, r10
+ retal r12
+
+ /*
+ * unsigned long find_first_bit(const unsigned long *addr,
+ * unsigned long size)
+ */
+ENTRY(find_first_bit)
+ cp.w r11, 0
+ reteq r11
+ mov r9, r11
+1: ld.w r8, r12[0]
+ cp.w r8, 0
+ brne .L_found
+ sub r12, -4
+ sub r9, 32
+ brgt 1b
+ retal r11
+
+ /*
+ * unsigned long find_next_bit(const unsigned long *addr,
+ * unsigned long size,
+ * unsigned long offset)
+ */
+ENTRY(find_next_bit)
+ lsr r8, r10, 5
+ sub r9, r11, r10
+ retle r11
+
+ lsl r8, 2
+ add r12, r8
+ andl r10, 31, COH
+ breq 1f
+
+ /* offset is not word-aligned. Handle the first (32 - r10) bits */
+ ld.w r8, r12[0]
+ sub r12, -4
+ lsr r8, r8, r10
+ brne .L_found
+
+ /* r9 = r9 - (32 - r10) = r9 + r10 - 32 */
+ add r9, r10
+ sub r9, 32
+ retle r11
+
+ /* Main loop. offset must be word-aligned */
+1: ld.w r8, r12[0]
+ cp.w r8, 0
+ brne .L_found
+ sub r12, -4
+ sub r9, 32
+ brgt 1b
+ retal r11
+
+ENTRY(generic_find_next_zero_le_bit)
+ lsr r8, r10, 5
+ sub r9, r11, r10
+ retle r11
+
+ lsl r8, 2
+ add r12, r8
+ andl r10, 31, COH
+ breq 1f
+
+ /* offset is not word-aligned. Handle the first (32 - r10) bits */
+ ldswp.w r8, r12[0]
+ sub r12, -4
+ lsr r8, r8, r10
+ brne .L_found
+
+ /* r9 = r9 - (32 - r10) = r9 + r10 - 32 */
+ add r9, r10
+ sub r9, 32
+ retle r11
+
+ /* Main loop. offset must be word-aligned */
+1: ldswp.w r8, r12[0]
+ cp.w r8, 0
+ brne .L_found
+ sub r12, -4
+ sub r9, 32
+ brgt 1b
+ retal r11
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