Javi Merino wrote: > > > >>> On Samsung's Exynos4 platform, while testing audio playback with > i2s > >>> interface, the above change causes the playback to freeze. The > >>> _thrd_active(thrd) call always returns '1' and hence _start(thrd) > is > >>> not getting called. > >> > >> If _thrd_active(thrd) returns '1', that means there is an active > >> transfer still running or, if it has finished, you haven't called > >> pl330_update() to acknowledge that. pl330_update() calls _start() > as > >> soon as it can. > >> > >> drivers/dma/pl330.c registers the irq handler in pl330_probe(), so > >> when > >> the transaction finishes, pl330_update() should clear it and call > >> _start(). If there is any outstanding transaction, it should start > >> straight away. If there isn't, it would mark the channel as free, > so > >> _thrd_active() should return '0'. If _thrd_active() is still '1', > then > >> something has gone wrong in the way. > >> > >> Does this shed some light? > >> > > > > Your patch makes the memcpy operation on dmatest.c and net DMA be > frozen too > > as well as Samsung audio playback. > > Is the IRQ correctly registered in drivers/dma/pl330.c:pl330_probe()? > Do you get interrupts when the transfer finish? Sure. IRQ works well. > > The only way I can think of that > ee3f615819404a9438b2dd01b7a39f276d2737f2 can break break something is > that you aren't calling pl330_update() at all. > > > With our patch, common DMA memcpy sequence may be changed. > > Which one is "our patch"? I'm sorry, I'm not subscribed to any of the > lists so I may have missed something. Sorry to make you confused. I mean.. "With your patch, common DMA memcpy sequence may be changed." Your patch brings the side effect that freezes dma transmits. > > Cheers, > Javi > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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