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Why does SGDMA block change my other device memory ranges?

Altera_Forum
Honored Contributor II
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I have noticed this odd behavior. I am running 7.2sp3 SOPC builder, when I add the SGDMA component all the addresses of the devices in the test example start to overlap. This is on the Stratix III Nios II standard sopc file.  

 

I have noticed on my Cyclone III Nios II Development Kit that the web server sopc file has the addresses of all the devices are at least 0x200 away from each other. 

 

Is there something about the behavior of the SGDMA block that prevents other devices from having small memory ranges ? 

 

Example from Stratix III Nios II sopc file :  

 

Original :  

sys_clk_timer 0x1000 - 0x101f  

high_res_timer 0x1020 - 0x103f 

sys_pll 0x1040 - 0x105f 

... 

 

After you add the SGDMA :  

sys_clk_timer 0x1000 - 0x10ff 

high_res_timer 0x1020 - 0x11ff ( * BROKEN OVERLAP * ) 

sys_pll 0x1040 - 0x113f ( * BROKEN OVERLAP * )  

... 

 

And since i am trying to add a Triple Speed Ethernet Mac to this SOPC file, i need to do it.  

 

I know the workaround is just move these devices further apart. I am just curious is this a known bug with SGDMA? ( Scatter Gather DMA )  

 

-Art
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