06.06.2019 19:32, Jon Hunter пишет: > > On 06/06/2019 16:18, Dmitry Osipenko wrote: > > ... > >>>> If I understood everything correctly, the FIFO buffer is shared among >>>> all of the ADMA clients and hence it should be up to the ADMA driver to >>>> manage the quotas of the clients. So if there is only one client that >>>> uses ADMA at a time, then this client will get a whole FIFO buffer, but >>>> once another client starts to use ADMA, then the ADMA driver will have >>>> to reconfigure hardware to split the quotas. >>> >>> The FIFO quotas are managed by the ADMAIF driver (does not exist in >>> mainline currently but we are working to upstream this) because it is >>> this device that owns and needs to configure the FIFOs. So it is really >>> a means to pass the information from the ADMAIF to the ADMA. >> >> So you'd want to reserve a larger FIFO for an audio channel that has a >> higher audio rate since it will perform reads more often. You could also >> prioritize one channel over the others, like in a case of audio call for >> example. >> >> Is the shared buffer smaller than may be needed by clients in a worst >> case scenario? If you could split the quotas statically such that each >> client won't ever starve, then seems there is no much need in the >> dynamic configuration. > > Actually, this is still very much relevant for the static case. Even if > we defined a static configuration of the FIFO mapping in the ADMAIF > driver we still need to pass this information to the ADMA. I don't > really like the idea of having it statically defined in two different > drivers. Ah, so you need to apply the same configuration in two places. Correct? Are ADMAIF and ADMA really two different hardware blocks? Or you artificially decoupled the ADMA driver?
