On Thu, 26 Jan 2023 at 15:44, <Ludovic.Desroches@xxxxxxxxxxxxx> wrote: > > On 30/12/2022 20:43, Tobias Schramm wrote: > > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe > > > > This commit fixes a race between completion of stop command and start of a > > new command. > > Previously the command ready interrupt was enabled before stop command > > was written to the command register. This caused the command ready > > interrupt to fire immediately since the CMDRDY flag is asserted constantly > > while there is no command in progress. > > Consequently the command state machine will immediately advance to the > > next state when the tasklet function is executed again, no matter > > actual completion state of the stop command. > > Thus a new command can then be dispatched immediately, interrupting and > > corrupting the stop command on the CMD line. > > Fix that by dropping the command ready interrupt enable before calling > > atmci_send_stop_cmd. atmci_send_stop_cmd does already enable the > > command ready interrupt, no further writes to ATMCI_IER are necessary. > > > > Signed-off-by: Tobias Schramm <t.schramm@xxxxxxxxxxx> > > Hi, > > In theory this changes make sense. I'm always afraid when something is > changed in this driver which handles many version of the IP... > > As we never encountered this issue until now, I can't really test this > fix. I checked on an old board at91sam9m10g45-ek that mmc is still > working and it's okay. > > So > Acked-by: Ludovic Desroches <ludovic.desroches@xxxxxxxxxxxxx> > > Regards, > Ludovic Thanks for your ack and thoughts! It's not clear to me whether the problem is hypothetical or in fact a real problem. Tobias can you help to fill in here? Nevertheless I have applied this for next, to allow more testing to be done. In the meantime, we can discuss whether we should add a stable tag or leave that to later as manual backports. [...] Kind regards Uffe
