Re: No console message in uCLinux

Altera_Forum · ‎10-30-2017

Dear all,

We are preparing one design for Arria 10 GX Development kit. That design is having following components:

Nios II (Gen2) Processor with MMU enabled
DDR4 memory.
On-chip memory as a reset vector (offset 0x0), exception vector (offset 0x20) and fast TLB miss exception vector (offset 0x100).
JTAG UART alongwith interval timer are also there in design. As suggested at http://www.alterawiki.com/wiki/uclinux#let.27s_start_it_step_by_step in Altera wiki, interval timer has been assigned IRQ0 and JTAG UART IRQ1.
We have ensured that total address span does not exceed 512MB. (Not sure why do we need this limitation?)

We checked design without MMU and by using Eclipse, Hello world program works nicely. But when we enabled MMU and built uCLinux image with that, no output is printed.

Note that image is getting downloaded successfully and also processor is started. See below.

$ nios2-download -g linux.initramfs.gz

using cable "usb-blasterii [usb-1]", device 1, instance 0x00

pausing target processor: ok

initializing cpu cache (if present)

ok

downloaded 4926kb in 8.7s (566.2kb/s)

verified ok

starting processor at address 0xc0000000

$ nios2-terminal.exe

nios2-terminal: connected to hardware target using jtag uart on cable

nios2-terminal: "usb-blasterii [usb-1]", device 1, instance 0

nios2-terminal: (use the ide stop button or ctrl-c to terminate)

No output after this. Could anybody give any hint to solve this?

Thank you,

Bhaumik

Altera_Forum · ‎02-10-2018

Hello,

First of all thanks to those who read my post and tried to see whether they can help or not.

At last, we were able to get past that issue.

I am sharing how we solved it here. Hope this could be helpful to someone in future.

We ensured that all peripherals (including memories) connected to Nios II's instruction master and data master are within address range: 0x0 to 0x1FFFF_FFFF. (Not very sure why we need to ensure this.)
We made following manual changes in DTS file generated from .sopcinfo
DDR4 memory is not located under memory section. Hence we manually edited it under memory section and comment it out from other section.
Under CPU section, 'altr' needs to be replaced with 'ALTR'. It seems that to use Nios II gen2 processor with Linux kernel version 3.4, this change is required. (I read this somewhere on Rocketboards.org)

Thank you and Have a Great Day!

Cheers,

Bhaumik