Difficulty reading into FPGA SDRAM from HPS

Altera_Forum · ‎03-31-2014

Hi,

I am running a slightly modified version of GHRD from rocketboards on my Cyclone V Dev Kit. Right now I am having difficulty trying to read

from FPGA SDRAM in Linux, which I connected to H2F bridge. The strange thing is, I can write to it, but when I try to read, it just hanged.

I am quite new in FPGA, if anyone has experienced the same thing, or has any clue to what have caused this, I appreciate if you could help me.

This is how I connected the SDRAM controller:

and settings:

Thanks.

Altera_Forum · ‎03-31-2014

After debugging with SignalTap, it seems that my local_cal_fail is asserted high, and local_init_done is low..

What can cause this?

Altera_Forum · ‎04-01-2014

I solved this, the reason is timing error (slack too much) :

1. Use afi_clk to drive both h2f axi master and the fifos

2. Use higher frequency on fpga_clk_50 to 125mhz