Le 25 sept. 2018 10:12 PM, Daniel Lezcano <daniel.lezcano@xxxxxxxxxx> a écrit : > > On 25/09/2018 15:38, Paul Cercueil wrote: > > > > Le 24 sept. 2018 9:14 AM, Daniel Lezcano <daniel.lezcano@xxxxxxxxxx> a écrit : > >> > >> On 24/09/2018 08:53, Paul Cercueil wrote: > >>> > >>> Le 24 sept. 2018 07:58, Daniel Lezcano <daniel.lezcano@xxxxxxxxxx> a écrit : > >>>> > >>>> On 24/09/2018 07:49, Paul Cercueil wrote: > >>>>> > >>>>> Le 24 sept. 2018 07:35, Daniel Lezcano <daniel.lezcano@xxxxxxxxxx> a > >>>>> écrit : > >>>>>> > >>>>>> On 24/09/2018 07:24, Paul Cercueil wrote: > >>>>>>> Hi Daniel, > >>>>>>> > >>>>>>> Le 24 sept. 2018 05:12, Daniel Lezcano > >>>>>>> <daniel.lezcano@xxxxxxxxxx> a écrit : > >>>>>>>> > >>>>>>>> On 21/08/2018 19:16, Paul Cercueil wrote: > >>>>>>>>> This driver handles the TCU (Timer Counter Unit) present on > >>>>>>>>> the Ingenic JZ47xx SoCs, and provides the kernel with a > >>>>>>>>> system timer, and optionally with a clocksource and a > >>>>>>>>> sched_clock. > >>>>>>>>> > >>>>>>>>> It also provides clocks and interrupt handling to client > >>>>>>>>> drivers. > >>>>>>>> > >>>>>>>> Can you provide a much more complete description of the timer > >>>>>>>> in order to make my life easier for the review of this patch? > >>>>>>> > >>>>>>> See patch [03/24], it adds a doc file that describes the > >>>>>>> hardware. > >>>>>> > >>>>>> Thanks, I went through but it is incomplete to understand what the > >>>>>> timer do. I will reverse-engineer the code but it would help if you > >>>>>> can give the gross approach. Why multiple channels ? mutexes and > >>>>>> completion ? > >>>>> > >>>>> Much of the complexity is because of the multi-purpose nature of the > >>>>> TCU channels. Each one can be used as timer/clocksource, or PWM. > >>>>> > >>>>> The driver starts by using channels 0 and 1 as system timer and > >>>>> clocksource, respectively, the other ones being unused for now. Then, > >>>>> *if* the PWM driver requests one of the channels in use by the > >>>>> timer/clocksource driver, say channel 0, the timer/clocksource driver > >>>>> will dynamically reassign the system timer to a free channel, from > >>>>> channel 0 to e.g. channel 2. Only in that case the completion/mutex > >>>>> are actually used. > >>>> > >>>> Why do you need to do this? Can't be the channels dedicated and reserved > >>>> for clocksource and clockevent? > >>> > >>> That's what I had in place (ingenic,timer-channel and ingenic,clocksource-channel DT properties), but Rob didn't want any linux-specific properties in the devicetree binding :( > >> > >> Isn't possible to specify the channel to use in the DT? like renesas16 ? > > > > That's what I did in V6 (and before), but Rob did not want me to add properties for Linux-specific concepts such as clocksource. > > Hmm, I remember something like that, yes but I did a delete of the > previous version when you posted the v7. Can you give a pointer to its > answer ? Yes, this was his answer: https://lkml.org/lkml/2018/7/25/508 Then mine: https://lkml.org/lkml/2018/7/30/883 -Paul