On 09-10-20, 14:29, Peter Ujfalusi wrote: > > > On 09/10/2020 14.15, Vinod Koul wrote: > >>> If for any any reason subsequent txn is for different direction, I would > >>> expect that parameters are set again before prep_ calls > >> > >> But in DEV_TO_DEV? > > > > Do we support that :D > > > >> If we have two peripherals, both needs config: > >> p1_config and p2_config > >> > >> What and how would one use the single peripheral_config? > > > > Since the config is implementation specific, I do not think it limits. > > You may create > > > > struct peter_config { > > struct p1_config; > > struct p2_config; > > }; > > The use case is: > MEM -DMA-> P1 -DMA-> P2 > or > P2 -DMA-> P1 -DMA-> MEM > or > MEM -DMA-> P2 > or > P2 -DMA-> MEM > or > MEM -DMA-> P1 -DMA-> MEM > > How would the DMA guess what it should do? How would the independent P1 > and P2 would know how to set up the config?
As I said, we do not support DEV_TO_DEV yet :) Question is how would p1<-->p2 look, will p1 initiate a DMA txn or p2..? who will configure these.. Do you have a real world example in horizon... -- ~Vinod