[U-Boot] STM32F746 Discovery - No serial output?

Patrice CHOTARD patrice.chotard at st.com
Tue Jan 23 08:13:28 UTC 2018


Hi Francois

Is it mandatory for you to get serial output on USART6 ?
Because default console output is on USART1 using the USB STLINK connector.

In my case, v2018.01 is working fine in SPL mode. I just disabled
CONFIG_SPL_OS_BOOT flag in stm32f746-disco_defconfig.

On my side, i flashed both binary with the following command:

openocd -f interface/stlink-v2-1.cfg -f board/stm32f7discovery.cfg \
-c "init" \
-c "reset init" \
-c "flash probe 0" \
-c "flash info 0" \
-c "flash write_image erase $UBOOT_PATH/spl/u-boot-spl.bin 0x08000000" \
-c "flash write_image erase $UBOOT_PATH/u-boot.bin 0x08008000"		  -c 
"reset run" \
-c "shutdown"

And i got :

U-Boot SPL 2018.01-00001-gbc00c01f0049 (Jan 23 2018 - 09:07:09)
Trying to boot from XIP


U-Boot 2018.01-00001-gbc00c01f0049 (Jan 23 2018 - 09:07:09 +0100)

Model: STMicroelectronics STM32F746-DISCO board
DRAM:  8 MiB
Flash: 1 MiB
Using default environment

In:    serial at 40011000
Out:   serial at 40011000
Err:   serial at 40011000
usr button is at LOW LEVEL
Net:
Warning: ethernet at 40028000 (eth0) using random MAC address - 
be:b0:c8:9a:8c:85
eth0: ethernet at 40028000
Hit SPACE in 3 seconds to stop autoboot.
U-Boot >


Regards

Patrice

On 01/22/2018 06:36 PM, Francois Dugast wrote:
> Thanks for the infos and the patches.
> 
> 1. Non SPL
> After disabling SPL in the U-Boot configuration and enabling USART6 in 
> the DTS with the patches you provided, there is still no output on this 
> serial interface after flashing U-Boot v2018.01 
> (stm32f746-disco_defconfig) with:
> $ openocd -f board/stm32f7discovery.cfg -c "program images/u-boot.bin 
> 0x08000000" -c "reset run" -c shutdown
> Serial output is coming on USART6 with U-Boot from 
> https://github.com/EmcraftSystems/u-boot so it is unlikely to be a 
> hardware issue.
> 
> 2. SPL
> I am not familiar with this mode on the stm32f746 disco. I have tried 
> copying the u-boot.bin generated with SPL enabled to the "DIS_F746NG" 
> MBED volume exposed by the card and the LED blinks in red and green for 
> a few seconds. Still, no output is coming through the /dev/ttyACM* 
> device. Could you give some hints about the steps to get it running?
> 
> Francois
> 
> On Tue, Jul 25, 2017 at 3:39 PM, Patrice CHOTARD <patrice.chotard at st.com 
> <mailto:patrice.chotard at st.com>> wrote:
> 
>     Another update you need to do, is to change the default uart in device
>     tree. By default uart1 is used, using the STLink usb port.
> 
>     To use the UART6 output on arduino UNO connector, applied the attached
>     patch.
> 
>     Patrice
> 
>     On 07/25/2017 02:20 PM, Patrice CHOTARD wrote:
>      > Hi Francois
>      >
>      > By default, stm32f746-disco is configured in SPL mode, that's what
>      > explain you don't get any output in the console
>      >
>      > To come back in non SPL mode, you can use the attached patch.
>      >
>      > Patrice
>      >
>      > On 07/21/2017 10:40 PM, Francois Dugast wrote:
>      >> Hi,
>      >>
>      >> I am trying to run the master on a STM32F746 Discovery board [1]
>     by using
>      >> stm32f746-disco_defconfig. It was built with
>     gcc-arm-none-eabi-5_4-2016q3
>      >> [2] and flashed with OpenOCD [3]. A USB-serial adapter is
>     connected to
>      >> USART6_RX and USART6_TX (pins D0 and D1 of the Arduino
>     connector) and
>      >> configured for 115200 8N1. No output coming out through the serial
>      >> interface. It is unlikely to be a hardware issue as output is
>     coming out
>      >> normally this way when using the U-Boot repository from Emcraft.
>      >>
>      >> I do not know what I am doing wrong, can you help me out?
>      >>
>      >> Cheers,
>      >> Francois
>      >>
>      >> [1] http://www.st.com/en/evaluation-tools/32f746gdiscovery.html
>     <http://www.st.com/en/evaluation-tools/32f746gdiscovery.html>
>      >> [2] https://launchpad.net/gcc-arm-embedded
>     <https://launchpad.net/gcc-arm-embedded>
>      >> [3] http://openocd.org
>      >> [4] https://github.com/EmcraftSystems/u-boot
>     <https://github.com/EmcraftSystems/u-boot>
>      >> _______________________________________________
>      >> U-Boot mailing list
>      >> U-Boot at lists.denx.de <mailto:U-Boot at lists.denx.de>
>      >> https://lists.denx.de/listinfo/u-boot
>     <https://lists.denx.de/listinfo/u-boot>
>      >>
>      >>
>      >>
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> 
> 


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