diff options
author | Haavard Skinnemoen <hskinnemoen@atmel.com> | 2006-09-26 02:32:13 -0400 |
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committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-09-26 11:48:54 -0400 |
commit | 5f97f7f9400de47ae837170bb274e90ad3934386 (patch) | |
tree | 514451e6dc6b46253293a00035d375e77b1c65ed /arch/avr32/mm/dma-coherent.c | |
parent | 53e62d3aaa60590d4a69b4e07c29f448b5151047 (diff) |
[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/mm/dma-coherent.c')
-rw-r--r-- | arch/avr32/mm/dma-coherent.c | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/arch/avr32/mm/dma-coherent.c b/arch/avr32/mm/dma-coherent.c new file mode 100644 index 000000000000..44ab8a7bdae2 --- /dev/null +++ b/arch/avr32/mm/dma-coherent.c | |||
@@ -0,0 +1,139 @@ | |||
1 | /* | ||
2 | * Copyright (C) 2004-2006 Atmel Corporation | ||
3 | * | ||
4 | * This program is free software; you can redistribute it and/or modify | ||
5 | * it under the terms of the GNU General Public License version 2 as | ||
6 | * published by the Free Software Foundation. | ||
7 | */ | ||
8 | |||
9 | #include <linux/dma-mapping.h> | ||
10 | |||
11 | #include <asm/addrspace.h> | ||
12 | #include <asm/cacheflush.h> | ||
13 | |||
14 | void dma_cache_sync(void *vaddr, size_t size, int direction) | ||
15 | { | ||
16 | /* | ||
17 | * No need to sync an uncached area | ||
18 | */ | ||
19 | if (PXSEG(vaddr) == P2SEG) | ||
20 | return; | ||
21 | |||
22 | switch (direction) { | ||
23 | case DMA_FROM_DEVICE: /* invalidate only */ | ||
24 | dma_cache_inv(vaddr, size); | ||
25 | break; | ||
26 | case DMA_TO_DEVICE: /* writeback only */ | ||
27 | dma_cache_wback(vaddr, size); | ||
28 | break; | ||
29 | case DMA_BIDIRECTIONAL: /* writeback and invalidate */ | ||
30 | dma_cache_wback_inv(vaddr, size); | ||
31 | break; | ||
32 | default: | ||
33 | BUG(); | ||
34 | } | ||
35 | } | ||
36 | EXPORT_SYMBOL(dma_cache_sync); | ||
37 | |||
38 | static struct page *__dma_alloc(struct device *dev, size_t size, | ||
39 | dma_addr_t *handle, gfp_t gfp) | ||
40 | { | ||
41 | struct page *page, *free, *end; | ||
42 | int order; | ||
43 | |||
44 | size = PAGE_ALIGN(size); | ||
45 | order = get_order(size); | ||
46 | |||
47 | page = alloc_pages(gfp, order); | ||
48 | if (!page) | ||
49 | return NULL; | ||
50 | split_page(page, order); | ||
51 | |||
52 | /* | ||
53 | * When accessing physical memory with valid cache data, we | ||
54 | * get a cache hit even if the virtual memory region is marked | ||
55 | * as uncached. | ||
56 | * | ||
57 | * Since the memory is newly allocated, there is no point in | ||
58 | * doing a writeback. If the previous owner cares, he should | ||
59 | * have flushed the cache before releasing the memory. | ||
60 | */ | ||
61 | invalidate_dcache_region(phys_to_virt(page_to_phys(page)), size); | ||
62 | |||
63 | *handle = page_to_bus(page); | ||
64 | free = page + (size >> PAGE_SHIFT); | ||
65 | end = page + (1 << order); | ||
66 | |||
67 | /* | ||
68 | * Free any unused pages | ||
69 | */ | ||
70 | while (free < end) { | ||
71 | __free_page(free); | ||
72 | free++; | ||
73 | } | ||
74 | |||
75 | return page; | ||
76 | } | ||
77 | |||
78 | static void __dma_free(struct device *dev, size_t size, | ||
79 | struct page *page, dma_addr_t handle) | ||
80 | { | ||
81 | struct page *end = page + (PAGE_ALIGN(size) >> PAGE_SHIFT); | ||
82 | |||
83 | while (page < end) | ||
84 | __free_page(page++); | ||
85 | } | ||
86 | |||
87 | void *dma_alloc_coherent(struct device *dev, size_t size, | ||
88 | dma_addr_t *handle, gfp_t gfp) | ||
89 | { | ||
90 | struct page *page; | ||
91 | void *ret = NULL; | ||
92 | |||
93 | page = __dma_alloc(dev, size, handle, gfp); | ||
94 | if (page) | ||
95 | ret = phys_to_uncached(page_to_phys(page)); | ||
96 | |||
97 | return ret; | ||
98 | } | ||
99 | EXPORT_SYMBOL(dma_alloc_coherent); | ||
100 | |||
101 | void dma_free_coherent(struct device *dev, size_t size, | ||
102 | void *cpu_addr, dma_addr_t handle) | ||
103 | { | ||
104 | void *addr = phys_to_cached(uncached_to_phys(cpu_addr)); | ||
105 | struct page *page; | ||
106 | |||
107 | pr_debug("dma_free_coherent addr %p (phys %08lx) size %u\n", | ||
108 | cpu_addr, (unsigned long)handle, (unsigned)size); | ||
109 | BUG_ON(!virt_addr_valid(addr)); | ||
110 | page = virt_to_page(addr); | ||
111 | __dma_free(dev, size, page, handle); | ||
112 | } | ||
113 | EXPORT_SYMBOL(dma_free_coherent); | ||
114 | |||
115 | #if 0 | ||
116 | void *dma_alloc_writecombine(struct device *dev, size_t size, | ||
117 | dma_addr_t *handle, gfp_t gfp) | ||
118 | { | ||
119 | struct page *page; | ||
120 | |||
121 | page = __dma_alloc(dev, size, handle, gfp); | ||
122 | |||
123 | /* Now, map the page into P3 with write-combining turned on */ | ||
124 | return __ioremap(page_to_phys(page), size, _PAGE_BUFFER); | ||
125 | } | ||
126 | EXPORT_SYMBOL(dma_alloc_writecombine); | ||
127 | |||
128 | void dma_free_writecombine(struct device *dev, size_t size, | ||
129 | void *cpu_addr, dma_addr_t handle) | ||
130 | { | ||
131 | struct page *page; | ||
132 | |||
133 | iounmap(cpu_addr); | ||
134 | |||
135 | page = bus_to_page(handle); | ||
136 | __dma_free(dev, size, page, handle); | ||
137 | } | ||
138 | EXPORT_SYMBOL(dma_free_writecombine); | ||
139 | #endif | ||