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UniPHY DDR3 simulation is slow

Altera_Forum
Honored Contributor II
814 Views

I am using Modelsim to simulate a simple UniPHY DDR3 design and it takes ~10 minutes to finish the DDR3 calibration and assert the local_init_done signal. I did enable the Skip Calibration option in MegaWizard. Is there a way to check if calibration is really skipped? The DDR3 I am using runs on 300 MHz (50Mhz reference clock), no hard memory interface, and Avalon is set to Half Rate. Is there any way to speed this up?

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Altera_Forum
Honored Contributor II
97 Views

If you are getting a message like this from ModelSim: 

 

# ** Warning: Design size of 31489 statements exceeds ModelSim Altera Starter recommended capacity. # Expect performance to be adversely affected.  

 

You should expect the simulation to be slow and the only way around it is to purchase a fully functional version of ModelSim.
Altera_Forum
Honored Contributor II
97 Views

 

--- Quote Start ---  

If you are getting a message like this from ModelSim: 

 

# ** Warning: Design size of 31489 statements exceeds ModelSim Altera Starter recommended capacity. # Expect performance to be adversely affected.  

 

You should expect the simulation to be slow and the only way around it is to purchase a fully functional version of ModelSim. 

--- Quote End ---  

 

 

I am not seeing this or similar messages in the Modelsim transcript. My project is very basic. It contains one instance of the DDR3 IP and I am trying to do a simple write followed by a read. What performance should I expect with the Starter edition of Modelsim? 

 

According to this article at http://www.altera.com/literature/hb/external-memory/emi_debug.pdf, full calibration should take 10 minutes and Skip calibration should take 3 minutes. Since my simulation time is right around 10 minutes, I am suspecting that I am doing a full calibration for some reason. Is there a way to check if calibration is really skipped?
Altera_Forum
Honored Contributor II
97 Views

 

--- Quote Start ---  

I am not seeing this or similar messages in the Modelsim transcript. My project is very basic. It contains one instance of the DDR3 IP and I am trying to do a simple write followed by a read. What performance should I expect with the Starter edition of Modelsim? 

 

According to this article at http://www.altera.com/literature/hb/external-memory/emi_debug.pdf, full calibration should take 10 minutes and Skip calibration should take 3 minutes. Since my simulation time is right around 10 minutes, I am suspecting that I am doing a full calibration for some reason. Is there a way to check if calibration is really skipped? 

--- Quote End ---  

 

 

Examine "calib_skip_steps" (e.g. "sim:/x_ddr3_tb/x_ddr3_inst/mem_if_ddr3_emif_0/p0/calib_skip_steps"); I believe it ought to be all 1's if you are actually skipping everything. 

In my simulation, 'local_init_done' goes high around 126us and takes maybe 2 minutes to get there, even with the project size warning I posted previously.
Altera_Forum
Honored Contributor II
97 Views

Hi all! 

 

May I know where to check "calib_skip_steps" from the example link ted gave:(e.g. sim:/x_ddr3_tb/x_ddr3_inst/mem_if_ddr3_emif_0/p0/calib_skip_steps")? 

 

My DDR3 UniPHY design is very basic with read and write operation. I use generated example design for simulation. 

 

For my case, I choose skip calibration mode and also disable the EMIF On-Chip Debug Toolkit in Diagnostics tab of the UniPHY-based controller MegaWizard GUI. However, my overall simulation time take atmost 1 hour. 

 

By the way, I also found Transcript from ModelSim state that:  

 

Code: 

# ** Warning: Design size of 17487 statements exceeds ModelSim Altera Starter recommended capacity.# Expect performance to be adversely affected. 

 

Is this really mean that fully purchase of ModelSim Altera can solve this issue? I would like to fasten the simulation as fast as possible like urs. 

 

Thanks!
Altera_Forum
Honored Contributor II
97 Views

Hi all, 

 

Can you tell me which device you guys are using? 

 

i am working on a MAX10 device and i don't see an option to skip calibration mode and to disable EMIF On-chip debug Toolkit. I am wondering this is not available for MAX10 devices. Any help on this issue is appreciated. 

 

Thanks
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