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Altera_Forum's avatar
Altera_Forum
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12 years ago

Unaligned access when trying to reach AXI-LW from U-Boot

Hello, I have a QSYS system, including some Avalon-MM peripherials connected to the AXI-LW interface of the HPS. For testing purposes I tried to read their registers from the serial consol...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

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That may not be an unaligned access, just an invalid address.

You might just need to check the address you should use when running under uboot.

I don't know whether uboot runs with the mmu enabled - in which case you need the virtual address the physical one is mapped to.

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Thank you. That is something I completely forgot as I always used a Nios II without MMU. Which would be the correct address?

The address I used is the offset from the QSYS system + the matching common address space region from the Cyclone V Handbook.