Re: [PATCH 1/1] spi: imx: support to set watermark level via DTS

From	Jiada Wang <jiada_wang@mentor.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH 1/1] spi: imx: support to set watermark level via DTS
Date	2017-01-06 10:30 +0100
Message-ID	<sWz0u-8bL-17@gated-at.bofh.it> (permalink)
References	<sW9z4-7s1-7@gated-at.bofh.it> <sWkEa-6xP-17@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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Hello Mark and Vladimir

On 01/05/2017 09:58 AM, Mark Brown wrote:
> On Thu, Jan 05, 2017 at 03:10:15PM +0900, Jiada Wang wrote:
>
>> Previously watermark level is configured to fifosize/2,
>> DMA mode can be used only when transfer length can be divided
>> by 'watermark level * bpw', which makes DMA mode not practical.
>> This patch adds new DTS property 'dma-wml', user can configure
>> DMA watermark level, by specify 'dma-wml' in corresponding ecspi
>> node.
> Doesn't this just move the problem around a bit - can we not have the
> driver figure out a more sensible watermark for each transfer rather
> than fixing one in the DT?
I would like to submit another version of patch to adjust watermark level
based on transfer length. to use largest number (< fifosize / 2 ) which 
can divide
(transfer_length / bytes_per_work).

Thanks,
Jiada

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[PATCH 1/1] spi: imx: support to set watermark level via DTS Jiada Wang <jiada_wang@mentor.com> - 2017-01-05 07:20 +0100
  Re: [PATCH 1/1] spi: imx: support to set watermark level via DTS Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com> - 2017-01-05 13:50 +0100
  Re: [PATCH 1/1] spi: imx: support to set watermark level via DTS Mark Brown <broonie@kernel.org> - 2017-01-05 19:10 +0100
    Re: [PATCH 1/1] spi: imx: support to set watermark level via DTS Jiada Wang <jiada_wang@mentor.com> - 2017-01-06 10:30 +0100

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