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Date:   Wed, 15 Jul 2020 16:43:15 +0530
From:   Vinod Koul <vkoul@kernel.org>
To:     Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc:     Peter Ujfalusi <peter.ujfalusi@ti.com>,
        Serge Semin <fancer.lancer@gmail.com>,
        Viresh Kumar <vireshk@kernel.org>,
        Dan Williams <dan.j.williams@intel.com>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>,
        Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        Arnd Bergmann <arnd@arndb.de>,
        Rob Herring <robh+dt@kernel.org>, linux-mips@vger.kernel.org,
        devicetree@vger.kernel.org, dmaengine@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v7 04/11] dmaengine: Introduce max SG list entries
 capability
Message-ID: <20200715111315.GK34333@vkoul-mobl>
References: <20200709224550.15539-1-Sergey.Semin@baikalelectronics.ru>
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 <20200710092738.z7zyywe46mp7uuf3@mobilestation>
 <427bc5c8-0325-bc25-8637-a7627bcac26f@ti.com>
 <20200710161445.t6eradkgt4terdr3@mobilestation>
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On 10-07-20, 19:14, Serge Semin wrote:
> On Fri, Jul 10, 2020 at 02:51:33PM +0300, Peter Ujfalusi wrote:

> > Since we should be able to handle longer lists and this is kind of a
> > hint for clients that above this number of nents the list will be broken
> > up to smaller 'bursts', which when traversing could cause latency.
> > 
> > sg_chunk_len might be another candidate.
> 
> Ok. We've got four candidates:
> - max_sg_nents_burst
> - max_sg_burst
> - max_sg_chain
> - sg_chunk_len
> 
> @Vinod, @Andy, what do you think?

So IIUC your hw supports single sg and in that you would like to publish
the length of each chunk, is that correct? If so sg_chunk_len seems
apt..

-- 
~Vinod