Honored Contributor
Honored ContributorYou haven't done anything, the Altera supplied linker script goes out of its way to make life difficult!
For some reason the Altera linker script puts all the initialised memory into one contiguous block - at the end of one of the code areas - and adds code to alt_main() to copy it to the correct physical address. I'm not sure why you have a gap between the .rodata and .rwdata, a unix program has a gap there so that the permissions on the pages can be different (sometime a page-sized gap, rather than aligning the .rwdata on the next page). The real problems arise when you are trying to load into multiple internal memory areas when the 'code' memory area is unlikely to be large enough to hold the initialised data - especially when it is a big lookup table! My suspicions are that Altera do this for EPCS loads into external SDRAM (etc) when there is likely to be enough space that it doesn't matter. Whether the code arranges the copies in a suitable order (eg reverse copies from highest address) to ensure they don't crap on each other is dubious! For tightly coupled systems the whole linker script is wrong. The .rodata needs to be in the 'data' memory, not the 'code' memory. As do any jump tables generated by the compiler for switch statements - which cannot be done with the gcc 4 Altera built.
