Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > linux.kernel > #1738773
| Path | csiph.com!weretis.net!feeder4.news.weretis.net!newsfeed.CARNet.hr!news.spin.it!bofh.it!news.nic.it!robomod |
|---|---|
| From | Sricharan R <sricharan@codeaurora.org> |
| Newsgroups | linux.kernel |
| Subject | Re: [PATCH v4] dmaengine: qcom-bam: Process multiple pending descriptors |
| Date | Mon, 25 Sep 2017 09:00:02 +0200 |
| Message-ID | <utvx0-2Kk-5@gated-at.bofh.it> (permalink) |
| References | <ujtPQ-78t-5@gated-at.bofh.it> <utuUh-2ui-3@gated-at.bofh.it> |
| Dkim-Signature | v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1506322651; bh=Xg576PBE7SQn+4RdPbb78dPz3NQoBiGEF9spz9pMgjc=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=b0qYJYuliiYiPoyEoauvdD3+5U8v2ZLdu2ipKZ1ELjGznoFRsjPfNYuzKY2P6WYnL P/92f2xJ+YibZH4dt5PuEe/7zZCcn0r6UxPM1FOMJ+S4naC18sgSB6J5ynAfnvL+Al j8JD/bz7/01/ubQT4pVgJwSIjl9789Z6OX819/Z8= |
| Dkim-Signature | v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1506322651; bh=Xg576PBE7SQn+4RdPbb78dPz3NQoBiGEF9spz9pMgjc=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=b0qYJYuliiYiPoyEoauvdD3+5U8v2ZLdu2ipKZ1ELjGznoFRsjPfNYuzKY2P6WYnL P/92f2xJ+YibZH4dt5PuEe/7zZCcn0r6UxPM1FOMJ+S4naC18sgSB6J5ynAfnvL+Al j8JD/bz7/01/ubQT4pVgJwSIjl9789Z6OX819/Z8= |
| Dmarc-Filter | OpenDMARC Filter v1.3.2 smtp.codeaurora.org EA8366025D |
| Authentication-Results | pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org |
| Authentication-Results | pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=sricharan@codeaurora.org |
| User-Agent | Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.3.0 |
| MIME-Version | 1.0 |
| Content-Type | text/plain; charset=utf-8 |
| Content-Language | en-US |
| Content-Transfer-Encoding | 7bit |
| Sender | robomod@news.nic.it |
| List-ID | <linux-kernel.vger.kernel.org> |
| X-Mailing-List | linux-kernel@vger.kernel.org |
| Approved | robomod@news.nic.it |
| Lines | 72 |
| Organization | linux.* mail to news gateway |
| X-Original-Cc | absahu@codeaurora.org, andy.gross@linaro.org, david.brown@linaro.org, dan.j.williams@intel.com, linux-arm-msm@vger.kernel.org, linux-soc@vger.kernel.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, dmaengine-owner@vger.kernel.org, stanimir.varbanov@linaro.org, architt@codeaurora.org |
| X-Original-Date | Mon, 25 Sep 2017 12:27:25 +0530 |
| X-Original-Message-ID | <ffebe592-6083-8fc2-ff78-6f18b750a8dc@codeaurora.org> |
| X-Original-References | <1503932424-4527-1-git-send-email-sricharan@codeaurora.org> <20170925062055.GA30097@localhost> |
| X-Original-Sender | linux-kernel-owner@vger.kernel.org |
| Xref | csiph.com linux.kernel:1738773 |
Show key headers only | View raw
On 9/25/2017 11:50 AM, Vinod Koul wrote: > On Mon, Aug 28, 2017 at 08:30:24PM +0530, Sricharan R wrote: >> The bam dmaengine has a circular FIFO to which we >> add hw descriptors that describes the transaction. >> The FIFO has space for about 4096 hw descriptors. >> >> Currently we add one descriptor and wait for it to >> complete with interrupt and then add the next pending >> descriptor. In this way, the FIFO is underutilized >> since only one descriptor is processed at a time, although >> there is space in FIFO for the BAM to process more. >> >> Instead keep adding descriptors to FIFO till its full, >> that allows BAM to continue to work on the next descriptor >> immediately after signalling completion interrupt for the >> previous descriptor. >> >> Also when the client has not set the DMA_PREP_INTERRUPT for >> a descriptor, then do not configure BAM to trigger a interrupt >> upon completion of that descriptor. This way we get a interrupt >> only for the descriptor for which DMA_PREP_INTERRUPT was >> requested and there signal completion of all the previous completed >> descriptors. So we still do callbacks for all requested descriptors, >> but just that the number of interrupts are reduced. >> >> CURRENT: >> >> ------ ------- --------------- >> |DES 0| |DESC 1| |DESC 2 + INT | >> ------ ------- --------------- >> | | | >> | | | >> INTERRUPT: (INT) (INT) (INT) >> CALLBACK: (CB) (CB) (CB) >> >> MTD_SPEEDTEST READ PAGE: 3560 KiB/s >> MTD_SPEEDTEST WRITE PAGE: 2664 KiB/s >> IOZONE READ: 2456 KB/s >> IOZONE WRITE: 1230 KB/s >> >> bam dma interrupts (after tests): 96508 >> >> CHANGE: >> >> ------ ------- ------------- >> |DES 0| |DESC 1 |DESC 2 + INT | >> ------ ------- -------------- >> | >> | >> (INT) >> (CB for 0, 1, 2) >> >> MTD_SPEEDTEST READ PAGE: 3860 KiB/s >> MTD_SPEEDTEST WRITE PAGE: 2837 KiB/s >> IOZONE READ: 2677 KB/s >> IOZONE WRITE: 1308 KB/s >> >> bam dma interrupts (after tests): 58806 > > Applied, thanks. > > Sorry for the delay, bad timing I guess :) > Sure np, Thanks for that. Regards, Sricharan -- "QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation
Back to linux.kernel | Previous | Next — Previous in thread | Find similar | Unroll thread
Re: [PATCH v4] dmaengine: qcom-bam: Process multiple pending descriptors Vinod Koul <vinod.koul@intel.com> - 2017-09-25 08:20 +0200 Re: [PATCH v4] dmaengine: qcom-bam: Process multiple pending descriptors Sricharan R <sricharan@codeaurora.org> - 2017-09-25 09:00 +0200
csiph-web