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authorChris Zankel <chris@zankel.net>2008-11-06 09:40:46 -0500
committerChris Zankel <chris@zankel.net>2008-11-06 13:25:09 -0500
commit367b8112fe2ea5c39a7bb4d263dcdd9b612fae18 (patch)
tree9f3349189718dd2c5678faf0ab38f389786b6925 /arch/xtensa/include/asm/dma.h
parent206ead28377fee86b129637edada8c77816cc0d6 (diff)
xtensa: move headers files to arch/xtensa/include
Move all header files for xtensa to arch/xtensa/include and platform and variant header files to the appropriate arch/xtensa/platforms/ and arch/xtensa/variants/ directories. Moving the files gets also rid of all uses of symlinks in the Makefile. This has been completed already for the majority of the architectures and xtensa is one out of six missing. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Chris Zankel <chris@zankel.net>
Diffstat (limited to 'arch/xtensa/include/asm/dma.h')
-rw-r--r--arch/xtensa/include/asm/dma.h61
1 files changed, 61 insertions, 0 deletions
diff --git a/arch/xtensa/include/asm/dma.h b/arch/xtensa/include/asm/dma.h
new file mode 100644
index 00000000000..e30f3abf48f
--- /dev/null
+++ b/arch/xtensa/include/asm/dma.h
@@ -0,0 +1,61 @@
1/*
2 * include/asm-xtensa/dma.h
3 *
4 * This file is subject to the terms and conditions of the GNU General Public
5 * License. See the file "COPYING" in the main directory of this archive
6 * for more details.
7 *
8 * Copyright (C) 2003 - 2005 Tensilica Inc.
9 */
10
11#ifndef _XTENSA_DMA_H
12#define _XTENSA_DMA_H
13
14#include <asm/io.h> /* need byte IO */
15
16/*
17 * This is only to be defined if we have PC-like DMA.
18 * By default this is not true on an Xtensa processor,
19 * however on boards with a PCI bus, such functionality
20 * might be emulated externally.
21 *
22 * NOTE: there still exists driver code that assumes
23 * this is defined, eg. drivers/sound/soundcard.c (as of 2.4).
24 */
25#define MAX_DMA_CHANNELS 8
26
27/*
28 * The maximum virtual address to which DMA transfers
29 * can be performed on this platform.
30 *
31 * NOTE: This is board (platform) specific, not processor-specific!
32 *
33 * NOTE: This assumes DMA transfers can only be performed on
34 * the section of physical memory contiguously mapped in virtual
35 * space for the kernel. For the Xtensa architecture, this
36 * means the maximum possible size of this DMA area is
37 * the size of the statically mapped kernel segment
38 * (XCHAL_KSEG_{CACHED,BYPASS}_SIZE), ie. 128 MB.
39 *
40 * NOTE: When the entire KSEG area is DMA capable, we substract
41 * one from the max address so that the virt_to_phys() macro
42 * works correctly on the address (otherwise the address
43 * enters another area, and virt_to_phys() may not return
44 * the value desired).
45 */
46
47#define MAX_DMA_ADDRESS (PAGE_OFFSET + XCHAL_KIO_SIZE - 1)
48
49
50/* Reserve and release a DMA channel */
51extern int request_dma(unsigned int dmanr, const char * device_id);
52extern void free_dma(unsigned int dmanr);
53
54#ifdef CONFIG_PCI
55extern int isa_dma_bridge_buggy;
56#else
57#define isa_dma_bridge_buggy (0)
58#endif
59
60
61#endif