On 11-11-22, 10:42, Sireesh Kodali wrote: > On Fri Nov 4, 2022 at 6:10 PM IST, Vinod Koul wrote: > > On 27-10-22, 10:44, Sireesh Kodali wrote: > > > The IPA v2.x block, found on some older Qualcomm SoCs, uses BAM DMA to > > > send and receive packets from the AP. It also uses BAM to receive > > > commands from the AP (and possibly the modem). These commands are > > > encoded as "Immediate Commands". They vary from regular BAM DMA > > > commands. Adding support for immediate commands is trivial, but requires > > > also adding Immediate Commands to the dmaengine API, which is what this > > > patch series does. > > > > Can you explain a bit more. I understand you need "Immediate Commands" > > but am really reluctant to add another interface to support a specific > > use case > > > > Apologies for the delayed response > > BAM supports both regular commands, and "immediate commands". Currently, > commands are used by the Qualcom NAND chip driver, while "immediate > commands" are intended to be used by the (yet to be mainlined) IPA > driver. From the BAM driver perspective, both immediate and regular > commands are simply a matter of setting the appropriate flag in the > descriptor. I don't have access to the documentation on BAM to know > exactly how these two modes differ, however I do know they are not > interchangable. If a different API is suggested, I can change the > implementation as needed. Ok, can you please explain what is meant by 'regular' cmd and 'immediate', lets see what is required here -- ~Vinod
