author | Graeme Price <GRAEME.PRICE@NOKIA.COM> |
Fri, 15 Oct 2010 14:32:18 +0100 | |
changeset 15 | 307f4279f433 |
permissions | -rw-r--r-- |
15
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
1 |
<?xml version="1.0" encoding="utf-8"?> |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
2 |
<!-- Copyright (c) 2007-2010 Nokia Corporation and/or its subsidiary(-ies) All rights reserved. --> |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
3 |
<!-- This component and the accompanying materials are made available under the terms of the License |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
4 |
"Eclipse Public License v1.0" which accompanies this distribution, |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
5 |
and is available at the URL "http://www.eclipse.org/legal/epl-v10.html". --> |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
6 |
<!-- Initial Contributors: |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
7 |
Nokia Corporation - initial contribution. |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
8 |
Contributors: |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
9 |
--> |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
10 |
<!DOCTYPE concept |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
11 |
PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd"> |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
12 |
<concept id="GUID-C649DB97-F138-4C90-B177-16590F2E3F19-GENID-1-2-1-9-1-6-1-8-1-7-1-3-1" xml:lang="en"><title>DMA Channels</title><shortdesc>Describes how device drivers use DMA channels.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody> |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
13 |
<p>The DMAC has different DMA channels that can be configured for |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
14 |
different DMA transfers. For some peripherals, such as the Camera |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
15 |
and the Display controller, there can be dedicated DMA channels that |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
16 |
cannot be configured for DMA transfers by other peripherals. However, |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
17 |
drivers generally initialize and open a multi-purpose DMA channel |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
18 |
and use that channel to perform the DMA transfers.</p> |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
19 |
<p>Initialization and opening of DMA channels is done using the interface <xref href="GUID-83882548-FAC5-3EFF-92ED-14D1D9A85D37.dita"><apiname>TDmaChannel</apiname></xref>. </p> |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
20 |
<note>This class is designed only for single-thread client access. |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
21 |
When used by multi-threaded clients, synchronization mechanisms should |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
22 |
be provided by the driver. </note> |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
23 |
<p>DMA channels must be opened before use and closed after completion |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
24 |
of DMA operations. </p> |
307f4279f433
Initial contribution of the Adaptation Documentation.
Graeme Price <GRAEME.PRICE@NOKIA.COM>
parents:
diff
changeset
|
25 |
</conbody></concept> |