[alsa-devel] fsl_ssi.c: Getting channel slips with fsl_ssi.c in TDM (network) mode.

[Nicolin Chen]

On Wed, Oct 28, 2015 at 09:23:01AM +0100, Roberto Fichera wrote:
> On 10/27/2015 09:11 PM, Nicolin Chen wrote:
> > 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.
> 
> I'm my case I was never able to see an interrupt triggered when setting both RDMAE and TDMAE
> bits in the SIER register.

Your problem may not involve with hardware FIFO underrun at all
so it's quite normal for you to have no IRQ in my opinion.