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Altera_Forum
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11 years ago

Accessing specific memory in DMA

I am trying to interface fpga and yocto in DE2i-150 board using device driver. From software side I am using DMA for memory allocation. I have 3 input data. Two of them are 416 bit long and one is 32...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
11 years ago

I am trying to implement an application where in software side I have A(416 bits), B(416 bits), C(416 bits), D(32bits), E(32bits) which I have to pass to the fpga for computing some arithmetic operations. My output is of 96bits. I am new to this field, so I don't have much knowledge regarding this. What I have done is, I have followed "Using PCI express on DE4 boards" and implemented the driver as described there. I am sending the data using the function "alt_up_pci_read" and "alt_up_pci_dma_add". In my verilog files I have used a array of 32bit registers to store the 416 bit data coming from the software side. But I am not sure how this will work if I just DMA the values to the registers. Do I need to have some offset or anything like memory access or do some extra thing in that case? Or only input will suffice?