On Tue, Oct 27, 2015 at 08:13:44AM +0100, Markus Pargmann wrote: > > So, the dma priority doesn't seem to be the issue. It's now set in > > the device tree, and strangely it's set to priority 0 (the highest) > > along with the UARTS. priority 0 is just the highest in the device > > tree -- it gets remapped to priority 3 in the sdma driver. the DT > > exposes only 3 levels of DMA priority, low, medium, and high. I > > created a new level that maps to DMA priroity 7 (the highest in the > > hardware), but still got the problem. > > > > So, still something unknown causing dma to miss samples. must be in > > the dma ISR I would assume. I guess it's time to look into that. > Cc Nicolin, Fabio, Shawn > > Perhaps you have an idea about this? Off the top of my head: 1) Enable TUE0, TUE1, ROE0, ROE1 to see if there is any IRQ trigged. 2) Set the watermarks for both TX and RX to 8 while using burst sizes of 6. It'd be nicer to provisionally set these numbers using hard code than your current change depending on fifo_depth as it might be an odd value. 3) Try to enlarge the ALSA period size in the asound.conf or passing parameters when you do the playback/capture so that the number of interrupts from SDMA may reduce. You may also see if the reproducibility is somehow reduced or not. Nicolin _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
