AnsweredAssumed Answered

DMA from PCIe -P4080DS

Question asked by appalanaidu g on Feb 5, 2020
Latest reply on Feb 5, 2020 by ufedor



We are new to working on P4080DS and linux.


We are trying to access data from FPGA(configured as EP) through PCIe1 (root complex) in P4080DS board.

From linux user space, we are using "mmap64" function to access the FPGA data.


U-boot log shows the following lines: 


PCI host bridge /pcie@ffe200000 (primary) ranges:
MEM 0x0000000c00000000..0x0000000c1fffffff -> 0x00000000e0000000
IO 0x0000000ff8000000..0x0000000ff800ffff -> 0x0000000000000000
/pcie@ffe200000: PCICSRBAR @ 0xdf000000
/pcie@ffe200000: Setup 64-bit PCI DMA window
/pcie@ffe200000: DMA window size is 0xdf000000


Since "64-bit PCI DMA window" is set , how to access FPGA data through PCIe using DMA?


Any help is requested


Thank you in advance.