Re: Using IDMA1 ( or IDMA2 ) on 860

John Francis wrote:

May be I should have been more specific, yes I have
setup the PC15 pin to have correct direction.

Well, your description indicated you were expecting the
transition of DREQ to generate an interrupt.  This isn't
the case.  Have you connected a logic analyzer to the bus
and determined the DMA is working correctly?

/* version2 of GetChipAddress this WORKS why? */

Because you can't directly access physical bus addresses from
the kernel.  They have to be mapped to some virtual address.
The IMMR is mapped to a well known address that can generally
be used anywhere in the kernel.  Anything else must be mapped,
as your example shows.  Just make sure you do this _once_,
don't keep calling ioremap() over and over or you will exhaust
the VM space and get a different address every time.


	-- Dan

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