S3C24XX DMA Updates for Linux 2.6.18-rc4

Introduction

This document describes the updates to the DMA system on the S3C24XX series of SoCs.

2618-rc4-dma-fixes.patch

This patch contains the following

General debugging tidyups.
No warning in s3c2410_dma_lastxfer for state S3C2410_DMALOAD_1LOADED_1RUNNING.
Add more verbose errors for dma timeouts, including channel number and source function.
Validate the memory address of the buffer passed.
Check for S3C2410_DMA_IDLE in IRQ, if buffer done has stopped channel.
Do not call request_irq with IRQs disabled.
Added op S3C2410_DMAOP_STARTED.

The S3C2410_DMAOP_STARTED op is for when you want to call the dma start, with the device not yet requesting DMA. This call is for use after the device has started DMA requests, so that the DMA core can check for a buffer load, and enqueue another buffer if it is possible.

2618-rc4-dma-typerename.patch

The dma files do not follow the general linux guidelines for decleraing data types, so rename all the items that came from the old 2.4 port to be closer to the coding style.

The following enums are renamed:

s3c2410_dmasrc_t to enum s3c2410_dmasrc
s3c2410_chan_op_t to enum s3c2410_chan_op
s3c2410_dma_state_t to enum s3c2410_dma_state
s3c2410_dma_loadst_t to enum s3c2410_dma_loadst
s3c2410_dma_buffresult_t to enum s3c2410_dma_buffresult
enum s3c2410_chan_op_e to enum s3c2410_chan_op

And the following structures:

s3c2410_dma_buf_t to struct s3c2410_dma_buf
s3c2410_dma_chan_t to struct s3c2410_dma_chan
s3c2410_dma_stats_t to struct s3c2410_dma_stats

The following two find and perl command lines will do the above renames:

find . -type f -exec perl -p -i~ -e 's/s3c2410_dma_buf_t/struct s3c2410_dma_buf/g; s/s3c2410_dma_client_t/struct s3c2410_dma_client/g; s/s3c2410_dma_chan_t/struct s3c2410_dma_chan/g; s/s3c2410_dma_stats_t /struct s3c2410_dma_stats /g; s/s3c2410_dma_stats_s/s3c2410_dma_stats/g;' {} \;
find . -type f -exec perl -p -i~ -e 's/s3c2410_dmasrc_t/enum s3c2410_dmasrc/g;  s/s3c2410_chan_op_t/enum s3c2410_chan_op/g; s/s3c2410_chan_op_e/s3c2410_chan_op/g; s/s3c2410_dma_state_t/enum s3c2410_dma_state/g; s/s3c2410_dma_loadst_t/enum s3c2410_dma_loadst/g; s/s3c2410_dma_buffresult_t/enum s3c2410_dma_buffresult/g;' {} \;

2618-rc4-dma-tabbing.patch

Fix the tabbing in include/asm-arm/arch-s3c2410/dma.h, update the copyright information, remove the obsolete changelog and fix the definition of MAX_DMA_ADDRESS.

2618-rc4-dma-selection.patch

The patch changes the method of claiming the channels, to allow each cpu to select the relevant dma hardware mappings. This means that the same driver code can be used on the s3c2410, s3c2440, etc.

Each cpu provides the DMA system with a map of these new channels to the actual hardware channels that can support them, so that at claim time the mapping between virtual and hardware channels can be made.

2618-rc4-dma-map-s3c2410.patch

DMA mappings for the S3C2410 CPU.

2618-rc4-dma-map-s3c2440.patch

DMA mappings for the S3C2440 CPU.

2618-rc4-dma-map-s3c2442.patch

Share the DMA mappings for the S3C2410 with the S3C2442.