Am Sun, 13 Oct 2024 21:52:05 -0500 schrieb Bin Liu <binmlist@xxxxxxxxx>: > Hi, > > Somehow this email wasn’t cc’d to my company email account > b-liu@xxxxxx, so I am replying from my personal email which > subscribed to the mailing list, and sorry if the formatting is wrong > since I am writing this response on my phone. > > On Oct 12, 2024, at 7:27 AM, Andreas Kemnade <andreas@xxxxxxxxxxxx> > wrote: > > > > Am Fri, 11 Oct 2024 12:33:56 -0500 > > schrieb Judith Mendez <jm@xxxxxx>: > > > > Currently in omap_8250_shutdown, the dma->rx_running > >> flag is set to zero in omap_8250_rx_dma_flush. Next > >> pm_runtime_get_sync is called, which is a runtime > >> resume call stack which can re-set the flag. When the > >> call omap_8250_shutdown returns, the flag is expected > >> to be UN-SET, but this is not the case. This is causing > >> issues the next time UART is re-opened and omap_8250_rx_dma > >> is called. Fix by moving pm_runtime_get_sync before the > >> omap_8250_rx_dma_flush. > >> > >> Signed-off-by: Bin Liu <b-liu@xxxxxx> > >> Signed-off-by: Judith Mendez <jm@xxxxxx> > >> > > Is this a theorectical problem or some real practical problem? > > So you are running a system with runtime pm enabled on serial > > console. > > How did you come across this issue? > > I could run the serial console/getty with runtime pm autosuspend > > enabled without issues all the years. > > > Yes this is a real issue reported on AM335x. Please see the report > linked below. > > PROCESSOR-SDK-AM335X: Possible bug in 8250_omap UART driver - > Processors forum - Processors - TI E2E support forums e2e.ti.com > > Thanks for information, so it looks like material for backporting. Maybe add the link in the description and add the cc stable and add back the fixes tag. Regards, Andreas
