SDRAM access with Arria 10

[juvt1413]

Hi Zangman,

This is an awesome project and an incredibly detailed wiki! I truly appreciate the effort you've put into creating these instructions.

I’m working in a slightly different environment and would appreciate your guidance if possible. Here’s my setup:

I’m using the Enclustra Mercury AA1 module, which features an Arria 10 SoC and 8 Gbit (1 GByte) of DDR4 SDRAM. Enclustra provides its own build environment, which generates U-Boot, Linux, and Buildroot for me.

That said, I’m currently struggling to get FPGA-to-SDRAM access working, and I’m hoping you can help me troubleshoot. Here are my questions:

• In the /proc/iomem output (included below), the system RAM is listed as spanning the range 00000000-7fffffff. Since my SDRAM is 1 GByte, I expected the range to be 00000000-3fffffff. Am I misunderstanding something here?

• I noticed I don’t have the extlinux.conf file in the FAT section as described in your setup. Is there an equivalent file or location for this configuration in my environment that you’re aware of?

• Regarding the my_custom.dts file, where should I add or edit this in the U-Boot directory? I see many .dts files there, and I want to ensure I’m modifying the correct one.

• In Intel’s documentation, I came across references to "HPS Secure Firewalls." Isn't this the component where SDRAM access reservations or restrictions need to be configured?

Lastly, I noticed that the YouTube video links in your wiki appear to be broken (e.g., “Video unavailable” “This video is private”). If you could update those links or point to alternative resources, that would be greatly appreciated.

Thank you in advance for your time and support!

Best regards,

# cat /proc/iomem
00000000-7fffffff : System RAM
  00008000-00cfffff : Kernel code
  00e00000-00ef8067 : Kernel data
ff800000-ff801fff : ff800000.ethernet ethernet@ff800000
ff808000-ff808fff : ff808000.dwmmc0 dwmmc0@ff808000
ffb00000-ffb0fffe : ffb00000.usb usb@ffb00000
ffc02100-ffc0211f : serial
ffc02300-ffc023ff : ffc02300.i2c i2c@ffc02300
ffcfe400-ffcfe41f : ffd03000.fpga-mgr fpga-mgr@ffd03000
ffd03000-ffd030ff : ffd03000.fpga-mgr fpga-mgr@ffd03000
ffd05000-ffd050ff : rstmgr
ffda1000-ffda1fff : pdma@ffda1000
  ffda1000-ffda1fff : ffda1000.pdma pdma@ffda1000
ffe00000-ffe3ffff : ffe00000.sram sram@ffe00000