Messages in this thread |  | | Date | Thu, 16 Nov 2017 23:04:00 -0800 | From | Bjorn Andersson <> | Subject | Re: [PATCH] mailbox: txdone_method shouldn't always be reset |
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On Thu 16 Nov 22:47 PST 2017, Jassi Brar wrote: > On 16 Nov 2017 23:12, "Bjorn Andersson" <bjorn.andersson@linaro.org> wrote: > On Thu 16 Nov 09:06 PST 2017, Jassi Brar wrote: > > diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c > > index 674b35f..95e480e 100644 > > --- a/drivers/mailbox/mailbox.c > > +++ b/drivers/mailbox/mailbox.c > > @@ -124,7 +124,8 @@ static enum hrtimer_restart txdone_hrtimer(struct > > hrtimer *hrtimer) > > for (i = 0; i < mbox->num_chans; i++) { > > struct mbox_chan *chan = &mbox->chans[i]; > > > > - if (chan->active_req && chan->cl) { > > + if (chan->active_req && chan->cl && > > + chan->txdone_method == TXDONE_BY_POLL) { > > The hrtimer code will crash before reaching this point if the channel > wasn't TXDONE_BY_POLL when it was created, so this part is not needed. > > > We have one timer for all channels of a controller. While this channel may > be run by ACK, some other might need to be POLLed. And we want to avoid > polling this channel. >
Oh, you're right.
But the fact that the timer function will poll channels that are "upgraded" to ACK is a separate issue.
> > > txdone = chan->mbox->ops->last_tx_done(chan); > > if (txdone) > > tx_tick(chan, 0); > > @@ -418,7 +419,7 @@ void mbox_free_channel(struct mbox_chan *chan) > > spin_lock_irqsave(&chan->lock, flags); > > chan->cl = NULL; > > chan->active_req = NULL; > > - if (chan->txdone_method == TXDONE_BY_ACK) > > + if (chan->txdone_method == TXDONE_BY_ACK && > chan->mbox->txdone_poll) > > This should be enough, but the logic here is not obvious. This relies on > the fact that a mbox with txdone_poll would have been initialized as > txdone = POLL and that txdone now being ACK would imply that it was > "upgraded" in the request path. > > So at least this would have to be captured in a comment. > > > Sure I'll add a comment. >
Thanks
Regards, Bjorn
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