where to send the EDMA request in the GPMC transmission?

Hi,

Check this thread: https://e2e.ti.com/support/arm/sitara_arm/f/791/t/348712

Thanks for your reply,i want to know where to create the request signal ,for the example of 8237 ,we use the DREQ to create a request signal.
now ,how can i create a EDMA request signal ?

when the FPGA want to start an EDMA transmission,how can he tell the EDMA ?

There are three AM335X processor pins: xdma_event_intr[2:0] that can be used for this purpose.

for 8237 example ,if the peripheral device want to start a dma request ,he must send an request signal to 8237 by DREQ, then wait for the reply from 8237 by DACK,then start the DMA transmission.Now , does we have any similar mechanism between the GPMC and the EDMA?

a dma chip for x86 ，if we have any any similar mechanism like "request, arbitration,reply"between the GPMC and EDMA?

OK ,thank you very much for your reply!

Now,i set corresponding bit in EESRH,connect XDMA_EVENT_INTR1 to the FPGA,if FPGA give a high level to XDMA_EVENT_INTR1 , an EDMA transmission can start,is that right?

Hi,

Yes if all is set correctly this should be the behavior.
What I could add is: check if you've set the dmas = <> & dma-names = <> in your gpmc device tree node.

Best Regards,
Yordan

i have set the edmas.but i don't understand how to set the gpmc device tree?

another quetion,there are only three pins for EDMA request :XDMA_EVENT_INTR0-2,but there are 64 events for EDMA,if we use XDMA_EVENT_INTR1 for GPMC,how can he know he is for the EDMA transmission for GPMC module ,but not for the other 63 modules?