Altera PCI Express Development Kit: Linux DMA Driver

Actually, it looks like the read is causing problems. EPLAST increments about 10-12 every iteration, but then freezes at 253. This is one less than 254, which is required to exit the loop that waits for the completion. The write look ok, since EPLAST = n = 254 at the last iteration. I don't know... maybe Likewise can help you better here, but I feel like it's firmware if you haven't modified the driver, other than the bar_min_len array. Are you still using 7.2? Try 9.0... the driver authors report problems depending on different Quartus compilation versions.