Re: moving to same chip, different board: no console output

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

Hello David,

On 06.06.25 16:43, David Picard wrote:
> Hello,
> 
> I am working on a project for which we selected an Intel/Altera Cyclone 5 SoC FPGA (an FPGA with an ARM core). As the project evolves, I have to change boards and I am facing issues to boot: absolutely no output on the serial console (USB virtual COM port), not even from Barebox.
> 
> Previous working configuration:
> - SD card image produced by Buildroot with Barebox as the bootloader
> - Terasic ADC-SoC demo board, booting from the SD card.
> https://www.terasic.com.tw/cgi-bin/page/archive.pl?Language=English&No=1061&PartNo=1
> 
> Current non-working configuration:
> - Eclustra Mercury+ SA2 module, also with a Cyclone 5, plus SDRAM, RTC, QSPI flash, etc. I think that the main difference between both Cyclone 5 chips is the size of the logic section is bigger on the module. The module has more RAM.
> https://www.enclustra.com/en/products/system-on-chip-modules/mercury-sa2/
> - Enclustra ST1 demo baseboard. It has a JTAG port, should this information be of interest.
> https://www.enclustra.com/en/products/base-boards/mercury-st1/
> 
> I the current configuration, I get no output on the serial console.

So you tried to use the exact same image on both boards or were
there changes?

> What I did:
> - I checked the hardware configuration (switches to select booting from the SD card and USB config) with a bare-metal application provided by Enclustra.
> - I used Enclutra's .dts and .dtsi files, which differ very slightly from the Linux kernel tree files.
> - I checked how the SD card is connected: to the exact same pins in both configurations.
> - I had a look at Barebox menuconfig, but nothing caught my eye.
> 
> So, now I'm stuck, and I'm looking for some guidance.

You can try enabling CONFIG_DEBUG_LL and CONFIG_DEBUG_PBL and see if you
get some debugging output maybe. You'll have to choose which UART to use.

I think your new SoM may have different RAM and thus you can't use the
same image, but need one suitable to RAM integrated on your new board.

Cheers,
Ahmad

> 
> David
> 
> 
> 


-- 
Pengutronix e.K.                           |                             |
Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |