[PATCH 1/4] Add DMA sector to Documentation/powerpc/booting-without-of.txt file.

[Zhang Wei-r63237]

Hi, 

> -----Original Message-----
> From: Segher Boessenkool [mailto:segher at kernel.crashing.org] 
> 
> > +   k) DMA
> > +
> > +   This sector define DMA for dma-engine driver of Freescale
> 
> It's called a "device node" or "node", not a "sector".

Ok, "node".

> 
> > +    - compatible : Should be "fsl,mpc8xxx-dma"
> 
> Should _include_, not should _be_.  And none of this xxx
> business, of course.
> 

All right.

> > +    - extended : Set the DMA channel to work at extended 
> chain mode.
> > +                 If not set, the DMA channel will work at basic
> > +                 chain mode.
> 
> Call it "extended-chain-mode", perhaps?
> 

Is it maybe too long?

> > +    - reserved : Reserve the DMA channel to device.
> 
> What does this do?  Reserve it for what device, and where?
> The OS driver?
> 

Yes, it reserve for the special device, which must use the fixed
channel. Thus, reserve channels requested by that device.

And in the device node of dts file, you can use such as
"dma-channel=<&dma-ch0>" to reference the below channel:

dma-ch0: ch0 at 100 {
...
}

Thanks!
Wei.