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Altera_Forum's avatar
Altera_Forum
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14 years ago

U-Boot v2 aka Barebox

Hello, I'm inviting you to try this wonderfull bootloader named Barebox (here (http://barebox.org)). I added the nios2 arch to the project some times ago and now, we have some nios2 drivers ava...
Altera_Forum's avatar
Altera_Forum
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12 years ago

Hi,

After investigation, I found that exception raise come from __muldi3 and other operand operation. (_mult is used by cyc2ns()).

Maybe it's not only barebox related issue, but when barebox is on top on ddr3 space (our range ddr3 is 0x800 0000 to 0xfff ffff), this exception occurs randomly (but at least 10s after starting).

Another strange fact is, clock_source function are based on uint64_t, and exception seems to come form __multdi3, which is long long typed !

In fact, this exception doesn't occur with the same Nios2 design without MMU and Linux (with MMU).

Regards,

Christophe

FPGA : Cyclone V Altera DevKit

Tools : Quartus 12.1 WebEdition