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SubjectRe: [PATCH v9 2/2] Add Intel LGM SoC DMA support.
On 25-11-20, 18:39, Reddy, MallikarjunaX wrote:

> > > > > desc needs to be configure for each dma channel and the remapped address of
> > > > > the IGP & EGP is desc base adress.
> > > > Why should this address not passed as src_addr/dst_addr?
> > > src_addr/dst_addr is the data pointer. Data pointer indicates address
> > > pointer of data buffer.
> > >
> > > ldma_chan_desc_cfg() carries the descriptor address.
> > >
> > > The descriptor list entry contains the data pointer, which points to the
> > > data section in the memory.
> > >
> > > So we should not use src_addr/dst_addr as desc base address.
> > Okay sounds reasonable. why is this using in API here?
> descriptor base address needs to be write into the dma register (DMA_CDBA).

Why cant descriptor be allocated by damenegine driver, passed to client
as we normally do in prep_* callbacks ? Why do you need a custom API

--
~Vinod

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