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Altera_Forum
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19 years ago

Running Linux inplace, from EPCS or CFI

I have run into some problems continuing on in my development with the Altera Cyclone II DSP dev board and uCLinux, related to memory interfacing. (At this stage I have uCLinux running on this b...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
19 years ago

I did hack the scripts.

In uClinux-dist-test/linux-2.6.x/arch/nios2nommu/scripts/PTF/SystemPTF/Module.pm, after line 176, in function getSize{}, I added:

} elsif ($data_width == 64) {

$size = 1 << ($addr_width + 3)

} elsif ($data_width == 128) {

$size = 1 << ($addr_width + 4)

}

This is required to use more than 64 MB of RAM, so I did this to use 128 MB. I can&#39;t use the full 256MB that is on the DIMM, since the other peripherals still need to be mapped into memory.

I did think about trying to hack the SOPC build scripts. However, if there is a genuine restriction to 256MB in the instruction master of the Nios, then hacking the scripts will just break the CPU logic. I had a look at the generated VHDL, but there is just too much of it to manually edit it.