Hi Matthias, Jassi, On Fri, 2016-06-03 at 18:41 +0530, Jassi Brar wrote: > On Fri, Jun 3, 2016 at 4:48 PM, Matthias Brugger <matthias.bgg@xxxxxxxxx> wrote: > > On 03/06/16 08:12, Horng-Shyang Liao wrote: > >> On Thu, 2016-06-02 at 10:46 +0200, Matthias Brugger wrote: > > >>> I keep thinking about how to get rid of the two data structures, > >>> task_busy_list and the task_release_wq. We need the latter for the only > >>> sake of getting a timeout. > >>> > >>> Did you have a look on how the mailbox framework handles this? > >>> By the way, what is the reason to not implement the whole driver as a > >>> mailbox controller? For me, this driver looks like a good fit. > >> > >> > >> CMDQ needs to encode commands for GCE hardware. We think this behavior > >> should be put in CMDQ driver, and client just call CMDQ functions. > >> Therefore, if we want to use mailbox framework, cmdq_rec must be > >> mailbox client, and the others must be mailbox controller. > >> > > > > You mean the functions to fill the cmdq_rec and execute it? > > I think this should be part of the driver. > > > > Jassi, can you have a look on the interface this driver exports [0]. > > They are needed to actually create the message which will be send. > > Could something like this be part of a mailbox driver? > > > > [0] https://patchwork.kernel.org/patch/9140221/ > > > Packet creating/parsing should not be a part of controller driver. As > the log of this patch says, today it is used for only display but in > future it could work with other h/w as well, so it makes sense to have > mailbox api do the message queuing, the controller driver do the > send/receive and client drivers implement display and other h/w > specific packaging of data (protocol handling). > > So yes, I think this could use mailbox api. > > Cheers. Let me use display as an example to do some further explanation about CMDQ in advance. You can think CMDQ is a shadow register replacement. Therefore, we use cmdq_rec_write(_mask), cmdq_rec_wfe, and cmdq_rec_clear_event instead of accessing registers, and use cmdq_rec_flush(_async) instead of atomic swap. If we use mailbox to do the message queue, we can use mailbox framework to implement flush and callback. However, I don't think mailbox is suitable for cmdq_rec_write(_mask), cmdq_rec_wfe, and cmdq_rec_clear_event since they are just record some commands. Is this the same as your comment "Packet creating/parsing should not be a part of controller driver."? Therefore, do you mean we use mailbox framework to implement flush and callback and keep other interfaces? Just want to confirm that I get the correct idea from you. Many thanks for your kindly reply. Thanks, HS -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
