Subject: Re: Need to know about implementation of DMA on MIPS
To: Viswanath <>
From: Jochen Kunz <>
List: tech-kern
Date: 01/08/2004 18:30:39
On Wed, 07 Jan 2004 19:30:39 -0800
"Viswanath" <> wrote:

> As far as my knowledge the bus_dma_create, bus_dma_load,
> bus_dma_unload, bus_dma_sync are all machine independent codes is it
> correct.
It is machine dependent, but you might be able to use a generic
bus_dma(9) implementation common for all MIPS ports. PowerPC has
somthing like that, it seams MIPS too.

> How to go about writing the backend for on-chip DMA implementation for
> SIO on evbmips.
bus_dma(9) doesn't depend on the I/O hardware. It depends on the CPU
(for things like cache flushing) and the bus (ISA, EISA, PCI, ...) for
things like DMA bounce buffers or I/O MMUs.