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author | Jon Loeliger <jdl@freescale.com> | 2006-09-19 08:51:24 -0500 |
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committer | Jon Loeliger <jdl@freescale.com> | 2006-09-19 08:51:24 -0500 |
commit | afa98843e4665add11b69496341053b268156e3a (patch) | |
tree | 116878b6b94920a5f282d0a16e4b9ad9dfaf57ff /cpu/mpc824x/drivers/dma/README | |
parent | b440d0ef72e6278973d3220c10136a4c0624c286 (diff) | |
parent | aeec782b020930732eab075af97212c3f03afcae (diff) | |
download | u-boot-imx-afa98843e4665add11b69496341053b268156e3a.zip u-boot-imx-afa98843e4665add11b69496341053b268156e3a.tar.gz u-boot-imx-afa98843e4665add11b69496341053b268156e3a.tar.bz2 |
Merge branch 'master' of http://www.denx.de/git/u-boot
Conflicts:
board/stxxtc/Makefile
Diffstat (limited to 'cpu/mpc824x/drivers/dma/README')
-rw-r--r-- | cpu/mpc824x/drivers/dma/README | 100 |
1 files changed, 0 insertions, 100 deletions
diff --git a/cpu/mpc824x/drivers/dma/README b/cpu/mpc824x/drivers/dma/README deleted file mode 100644 index 06f4bc0..0000000 --- a/cpu/mpc824x/drivers/dma/README +++ /dev/null @@ -1,100 +0,0 @@ -CONTENT: - - dma.h - dma1.c - dma2.s - -WHAT ARE THESE FILES: - -These files contain MPC8240 (Kahlua) DMA controller -driver routines. The driver routines are not -written for any specific operating system. -They serves the purpose of code sample, and -jump-start for using the MPC8240 DMA controller. - -For the reason of correctness of C language -syntax, these files are compiled by Metaware -C compiler and assembler. - -ENDIAN NOTATION: - -The algorithm is designed for big-endian mode, -software is responsible for byte swapping. - -USAGE: - -1. The host system that is running on MPC8240 - or using MPC8240 as I/O device shall link - the files listed here. The memory location - of driver routines shall take into account of - that driver routines need to run in supervisor - mode and they process DMA controller interrupt. - -2. The host system is responsible for configuring - the MPC8240 including Embedded Utilities Memory - Block. Since the DMA controller on MPC8240 can - be accessed by either local 603e core or the host - that MPC8240 serves as I/O processor through host - PCI configuration, it is important that the local - processor uses EUMBBAR to access its local DMA - controller while the PCI master uses I/O - processor's PCSRBAR to access the DMA controller - on I/O device. - - To qualify whether is EUMBBAR or PCSRBAR, one - additional parameter is requied from the host - system, LOCAL or REMOTE so that the base value - can be correctly interpreted. - -3. If the host system is also using the EPIC unit - on MPC8240, the system can register the - DMA_ISR with the EPIC including other - desired resources. - - If the host system does not using the EPIC unit - on MPC8240, DMA_ISR function can be called for - each desired time interval. - - In both cases, the host system is free to - provide its own interrupt service routine. - -4. To start a direct mode DMA transaction, - use DMA_Bld_Curr with the start parameter - set to 1. - - To start a chaining mode DMA transaction, - the application shall build descriptors - in memory first, next, use DMA_Bld_Desp - with the start parameter set to 1. - -5. DMA_Start function clears, then sets the CS - bit of DMA mode register. - - DMA_Halt function clears the CS bit of DMA - mode register. - - These functions can be used to start and - halt the DMA transaction. - - If the chaining descriptors has been - modified since the last time a DMA - transaction started, use DMA_Chn_Cnt - function to let DMA controller process - the modified descriptor chain without - stopping or disturbing the current DMA - transaction. - - It is the host system's responsibility of - setting up the correct DMA transfer mode - and pass the correct memory address parameters. - -6. It is the host system's responsibility of - queueing the DMA I/O request. The host - system can call the DMA_ISR with its own - desired interrupt service subroutines to - handle each individual interrupt and queued - DMA I/O requests. - -7. The DMA driver routines contains a set - of utilities, Set and Get, for host system - to query and modify the desired DMA registers. |