> From: Andy Shevchenko [mailto:andriy.shevchenko@xxxxxxxxxxxxxxx] > Sent: Monday, September 28, 2015 4:46 PM > To: yitian <yitian.bu@xxxxxxxxxxxxxx>; 'Andy Shevchenko' > <andy.shevchenko@xxxxxxxxx>; 'Viresh Kumar' <viresh.kumar@xxxxxxxxxx> > Cc: 'Viresh Kumar' <vireshk@xxxxxxxxxx>; 'Vinod Koul' > <vinod.koul@xxxxxxxxx>; 'Dan Williams' <dan.j.williams@xxxxxxxxx>; > 'dmaengine' <dmaengine@xxxxxxxxxxxxxxx>; 'Linux Kernel Mailing List' > <linux-kernel@xxxxxxxxxxxxxxx> > Subject: Re: [PATCH 1/1] dmaengine: dw: resolve recursion lock when > audio playback > > On Mon, 2015-09-28 at 15:23 +0800, yitian wrote: > > > > > > From: Andy Shevchenko [mailto:andy.shevchenko@xxxxxxxxx] > > > Sent: Monday, September 28, 2015 3:06 PM > > > To: Viresh Kumar <viresh.kumar@xxxxxxxxxx> > > > Cc: yitian <yitian.bu@xxxxxxxxxxxxxx>; Viresh Kumar > > > <vireshk@xxxxxxxxxx>; Andy Shevchenko > > > <andriy.shevchenko@xxxxxxxxxxxxxxx>; Vinod Koul < > > > vinod.koul@xxxxxxxxx>; > > > Dan Williams <dan.j.williams@xxxxxxxxx>; dmaengine > > > <dmaengine@xxxxxxxxxxxxxxx>; Linux Kernel Mailing List > > > <linux-kernel@xxxxxxxxxxxxxxx> > > > Subject: Re: [PATCH 1/1] dmaengine: dw: resolve recursion > > > > I am not sure if this is a sane way of doing that, and we were > > > > scanning > > > > the descriptors for some valid reason.. > > > > > > Actually one of the patches in a pile sitting in my private repo is > > > also including similar change. In my case the reason is to support > > > cyclic transfers natively. > > > > > > > Yes, i am using DW DMAC to support cyclic transfer. > > Currently it is very easy to get recursion lock crash, but > > after this patch everything is fine on my device. > > What is an actual hardware you are running kernel on? > Hi Andy: I am using a FPGA, with Cortex-A5 core, Designware I2S IP, Designware DMAC IP. What I was done is to run tinyplay and tinycap to test the playback and capture function on the FPGA. With my change, both of them are okay now. I didn't push the patch which added cyclic DMA support for dw DMAC because I didn't make it decent enough yet. -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
