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-rw-r--r--Documentation/arm/Samsung-S3C24XX/DMA.txt46
-rw-r--r--Documentation/arm/Samsung-S3C24XX/Overview.txt21
2 files changed, 63 insertions, 4 deletions
diff --git a/Documentation/arm/Samsung-S3C24XX/DMA.txt b/Documentation/arm/Samsung-S3C24XX/DMA.txt
new file mode 100644
index 000000000000..37f4edcc5d87
--- /dev/null
+++ b/Documentation/arm/Samsung-S3C24XX/DMA.txt
@@ -0,0 +1,46 @@
+ S3C2410 DMA
+ ===========
+
+Introduction
+------------
+
+ The kernel provides an interface to manage DMA transfers
+ using the DMA channels in the cpu, so that the central
+ duty of managing channel mappings, and programming the
+ channel generators is in one place.
+
+
+DMA Channel Ordering
+--------------------
+
+ Many of the range do not have connections for the DMA
+ channels to all sources, which means that some devices
+ have a restricted number of channels that can be used.
+
+ To allow flexibilty for each cpu type and board, the
+ dma code can be given an dma ordering structure which
+ allows the order of channel search to be specified, as
+ well as allowing the prohibition of certain claims.
+
+ struct s3c24xx_dma_order has a list of channels, and
+ each channel within has a slot for a list of dma
+ channel numbers. The slots are searched in order, for
+ the presence of a dma channel number with DMA_CH_VALID
+ orred in.
+
+ If the order has the flag DMA_CH_NEVER set, then after
+ checking the channel list, the system will return no
+ found channel, thus denying the request.
+
+ A board support file can call s3c24xx_dma_order_set()
+ to register an complete ordering set. The routine will
+ copy the data, so the original can be discared with
+ __initdata.
+
+
+Authour
+-------
+
+Ben Dooks,
+Copyright (c) 2007 Ben Dooks, Simtec Electronics
+Licensed under the GPL v2
diff --git a/Documentation/arm/Samsung-S3C24XX/Overview.txt b/Documentation/arm/Samsung-S3C24XX/Overview.txt
index 28d014714ab8..c31b76fa66c4 100644
--- a/Documentation/arm/Samsung-S3C24XX/Overview.txt
+++ b/Documentation/arm/Samsung-S3C24XX/Overview.txt
@@ -8,13 +8,10 @@ Introduction
The Samsung S3C24XX range of ARM9 System-on-Chip CPUs are supported
by the 's3c2410' architecture of ARM Linux. Currently the S3C2410,
- S3C2440 and S3C2442 devices are supported.
+ S3C2412, S3C2413, S3C2440 and S3C2442 devices are supported.
Support for the S3C2400 series is in progress.
- Support for the S3C2412 and S3C2413 CPUs is being merged.
-
-
Configuration
-------------
@@ -26,6 +23,22 @@ Configuration
please check the machine specific documentation.
+Layout
+------
+
+ The core support files are located in the platform code contained in
+ arch/arm/plat-s3c24xx with headers in include/asm-arm/plat-s3c24xx.
+ This directory should be kept to items shared between the platform
+ code (arch/arm/plat-s3c24xx) and the arch/arm/mach-s3c24* code.
+
+ Each cpu has a directory with the support files for it, and the
+ machines that carry the device. For example S3C2410 is contained
+ in arch/arm/mach-s3c2410 and S3C2440 in arch/arm/mach-s3c2440
+
+ Register, kernel and platform data definitions are held in the
+ include/asm-arm/arch-s3c2410 directory.
+
+
Machines
--------