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T2080 DMA to access FPGA BLOCKRAM over PCIe

Question asked by Flaby Jacob on Feb 10, 2016
Latest reply on Jul 17, 2018 by Brett Stahlman

Hi all,


I have a t2080rdb based custom board

In UBoot, I have enabled DMA and it is able to access local DDR.

I need to access the FPGA BLOCKRAM connected on the PCIe3 using DMA.

PCIe3 memory map is done in the T208xRDB.h in the UBoot source code as follows,


#define CONFIG_SYS_PCIE3_MEM_VIRT       0xb0000000

#define CONFIG_SYS_PCIE3_MEM_BUS        0xe0000000

#define CONFIG_SYS_PCIE3_MEM_PHYS       0xc30000000ull

#define CONFIG_SYS_PCIE3_MEM_SIZE       0x10000000      /* 256M */

#define CONFIG_SYS_PCIE3_IO_VIRT        0xf8020000

#define CONFIG_SYS_PCIE3_IO_BUS         0x00000000

#define CONFIG_SYS_PCIE3_IO_PHYS        0xff8020000ull

#define CONFIG_SYS_PCIE3_IO_SIZE        0x00010000      /* 64k */


I am able to access BLOCKRAM from CPU as follows,

md  b0010000


But when I give the same address as the destination address for DMA, it is giving me an error(TE bit set in the DMA Status Register).


Can somebody help me to proceed further?