Nios doesn't boot using custom bootloader

Hi Slacker,

Thanks for your answer.

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Be sure that you understand that the EPCS bootloader does not reside in the EPCS flash, itself, but rather in a small onchip (i.e. _on_ FPGA) memory that is a part of the epcs_controller. Any changes you make to the EPCS bootloader must be built into that onchip memory and re-compiled in Quartus II.

If you already understand that portion (it looks like you do), then you're already making sure that this happens and that the instructions you see in that onchip memory match what you'd expect to see in your customer bootloader.

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Yes I think I understand well Nios bootloader basics but in detail I am not sure that I am not missing anything.

For example:

- Are the Altera_wiki ASM sources ready to use without modification (except the epcs_controller base address and Nios image offset)?

- I have only mapped the cpu_reset_vector to the ROM containing the hex bootloader. Is there anything else to configure the Hardware?

Maybe I need to debug the Nios boot sequence to see if it can access the epcs.

I have import asm sources as "Custom Makefil for Nios II Software Build Tools Project" but I don't know how to run the debugger with this kind of project.

Do you know how it works?

Have you read how I generate the JIC file? I want to write the nios image at 0x400000 and boot at this address. Did I use the good commands to do it?

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Also, any reason that you're using 11.1sp2? It's a pretty old version is all. You could also replace it with non-assembly code as well. If I recall, there's a single command in the EPCS API that will pretty much do this for you...not sure if it will fit into the 1k bytes that are part of the epcs_controller though. You'd likely have to use another onchip memory....It would be easier to debug/test though.

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I use several IP and especially a commercial Transceiver IP developed on an old Quartus version. So I prefer to keep the same Quartus version with a known behavior during development.

I choose the ASM sources because it thought it was more simple as I didn’t need any custom modifications and knew nothing about bootloaders.

I create an 1KB onchip ROM to store the bootloader so I shouldn't be disturb by epcs_rom.

Thanks again.

ps: sorry to reply late, I had to debbug HW problems on other boards...