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authorHaavard Skinnemoen <hskinnemoen@atmel.com>2006-09-26 02:32:13 -0400
committerLinus Torvalds <torvalds@g5.osdl.org>2006-09-26 11:48:54 -0400
commit5f97f7f9400de47ae837170bb274e90ad3934386 (patch)
tree514451e6dc6b46253293a00035d375e77b1c65ed /arch/avr32/mm/dma-coherent.c
parent53e62d3aaa60590d4a69b4e07c29f448b5151047 (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.c139
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
14void 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}
36EXPORT_SYMBOL(dma_cache_sync);
37
38static 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
78static 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
87void *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}
99EXPORT_SYMBOL(dma_alloc_coherent);
100
101void 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}
113EXPORT_SYMBOL(dma_free_coherent);
114
115#if 0
116void *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}
126EXPORT_SYMBOL(dma_alloc_writecombine);
127
128void 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}
138EXPORT_SYMBOL(dma_free_writecombine);
139#endif