RE: [PATCH v7 1/2] Documentation: DT: dma: Add Xilinx zynqmp dma device tree binding documentation

From	Appana Durga Kedareswara Rao <appana.durga.rao@xilinx.com>
Newsgroups	linux.kernel
Subject	RE: [PATCH v7 1/2] Documentation: DT: dma: Add Xilinx zynqmp dma device tree binding documentation
Date	2016-05-03 11:20 +0200
Message-ID	<ruEEO-5sx-7@gated-at.bofh.it> (permalink)
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Hi Vinod,

> 
> PLEASE strip the crap from your MUA, better use a linux MUA

OK will fix Sorry for the noise...

> 
> 
> > >>>>> +- xlnx,include-sg	: Indicates the controller to operate in simple
> or
> > >>>>> +			  scatter gather dma mode
> > >>>>> +- xlnx,ratectrl		: Scheduling interval in terms of clock cycles for
> > >>>>> +			  source AXI transaction
> > >>>>> +- xlnx,overfetch	: Tells whether the channel is allowed to over
> > >>>>> +			  fetch the data
> > >>>>> +- xlnx,src-issue	: Number of AXI outstanding transactions on source
> > >>>> side
> > >>>>> +- xlnx,src-burst-len	: AXI length for data read. Support only power
> of
> > >>>>> +			  2 byte values.
> > >>>>> +- xlnx,dst-burst-len	: AXI length for data write. Support only power
> of
> > >>>>
> > >>>> These are all software runtime configuration parameters that you'd
> > >>>> want to change at runtime depending on which peripheral you are
> > >>>> targeting with a specific DMA transfer. These really do not belong into

> > Sorry, but that is just as broken. You need to derive those parameters from
> > the DMA transfer as they are transfer specific.
> 
> Right, for memcpy you should derive the parameters. Frankly burst size
> and lengths, rate control should be set to maximun to achives best
> performance on mecpy.  People want memcpy to be done asap

Ok Will fix in the next version of the patch...

Regards,
Kedar.

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Re: [PATCH v7 1/2] Documentation: DT: dma: Add Xilinx zynqmp dma  device tree binding documentation Vinod Koul <vinod.koul@intel.com> - 2016-05-02 12:10 +0200
  RE: [PATCH v7 1/2] Documentation: DT: dma: Add Xilinx zynqmp dma  device tree binding documentation Appana Durga Kedareswara Rao <appana.durga.rao@xilinx.com> - 2016-05-03 11:20 +0200

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