Under Linux 3.12.19, I'm using T1042 DMA engine to transfer data between CPU memory and FPGA memory (view as a 1MB BAR space on PCIe). From the CPU to the FPGA, the transfer works whatever the size. But from the FPGA to the CPU, the transfer works with a maximum length of 255 bytes and doesn't work from a length of 256 bytes.
PCIE error(s) detected | |
PCIE ERR_DR register: 0x00800000 | |
PCIE ERR_CAP_STAT register: 0x80000001 | |
PCIE ERR_CAP_R0 register: 0x00000800 | |
PCIE ERR_CAP_R1 register: 0x00000000 | |
PCIE ERR_CAP_R2 register: 0x00000000 | |
PCIE ERR_CAP_R3 register: 0x00000000 | |
fsl-elo-dma ffe100300.dma: chan0: Transfer Error! |
fsl-elo-dma ffe100300.dma: chan0: irq: unhandled sr 0x00000080
Thank you for your help.