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I get output via UART4, but not via ST-LINK and I cannot input anything regardless.

isca-dim
Associate II

Hello,

I am using the stm32mp157c-ev1 board. I used this guide from digi-key to install debian on it (

Debian: Getting Started with the STM32MP157), except in the parts where it says stm32mp157c-dk2 i replaced that with the appropriate '-ev1' suffix. I have also followed the same guide on discovery kit 2 board and it worked without issue.

The problem is that when I try to boot from the board via the UART4 through minicom, while everything looks to be booting correctly (minus this error: *ERROR* failed to attach bridge /soc/dsi@5a000000 to encoder DPI-31: -517). Meaning that it shows me the login prompt, however i cannot enter anything. I tried connecting a keyboard to the board and it still does not seem to receive any input.

Trying to connect via the st-link is even stranger as it shows me no output at all (even though CubeIDE is able to detect the ST-LINK S/N via the debugger). I have even done the ST-LINK upgrade from CubeIDE.

OUTPUT:

NOTICE:  CPU: STM32MP157CAA Rev.B
NOTICE:  Model: STMicroelectronics STM32MP157C eval daughter on eval mother
NOTICE:  Board: MB1263 Var1.0 Rev.C-02
NOTICE:  BL2: v2.5(release):v2.5
NOTICE:  BL2: Built : 16:14:51, Oct 10 2022
NOTICE:  BL2: Booting BL32
NOTICE:  SP_MIN: v2.5(release):v2.5
NOTICE:  SP_MIN: Built : 16:14:56, Oct 10 2022
 
 
U-Boot 2022.10 (Oct 10 2022 - 16:10:15 +0300)
 
CPU: STM32MP157CAA Rev.B
Model: STMicroelectronics STM32MP157C eval daughter on eval mother
Board: stm32mp1 in trusted - stm32image mode (st,stm32mp157c-ev1)
Board: MB1263 Var1.0 Rev.C-02
DRAM:  1 GiB
Clocks:
- MPU : 650 MHz
- MCU : 208.878 MHz
- AXI : 266.500 MHz
- PER : 24 MHz
- DDR : 533 MHz
stmfx stmfx@42: STMFX id: 0x7b, fw version: 3.03
Core:  285 devices, 43 uclasses, devicetree: board
WDT:   Started watchdog@5a002000 with servicing (32s timeout)
NAND:  1024 MiB
MMC:   STM32 SD/MMC: 0, STM32 SD/MMC: 1
Loading Environment from MMC... OK
In:    serial
Out:   serial
Err:   serial
invalid MAC address 0 in OTP 00:00:00:00:00:00
Net:   
Error: ethernet@5800a000 address not set.
No ethernet found.
 
Hit any key to stop autoboot:  0 
Boot over mmc0!
switch to partitions #0, OK
mmc0 is current device
Scanning mmc 0:4...
Found /boot/extlinux/extlinux.conf
Retrieving file: /boot/extlinux/extlinux.conf
1:      Linux 5.15.65-armv7-lpae-x30
Retrieving file: /boot/vmlinuz-5.15.65-armv7-lpae-x30
append: console=ttySTM0,115200 root=/dev/mmcblk0p4 ro rootfstype=ext4 rootwait
Retrieving file: /boot/dtbs/5.15.65-armv7-lpae-x30/stm32mp157c-ev1.dtb
Kernel image @ 0xc2000000 [ 0x000000 - 0xb93200 ]
## Flattened Device Tree blob at c4000000
   Booting using the fdt blob at 0xc4000000
   Loading Device Tree to cffe8000, end cffff920 ... OK
optee optee: OP-TEE api uid mismatch
optee optee: OP-TEE api uid mismatch
 
Starting kernel ...
 
[    0.000000] Booting Linux on physical CPU 0x0
.
.
.
.
.
 
[  OK  ] Started WPA supplicant.
[  OK  ] Started Authorization Manager.
         Starting Modem Manager...
[  OK  ] Finished Remove Stale Onli…ext4 Metadata Check Snapshots.
[  OK  ] Started Network Manager.
[  OK  ] Reached target Network.
         Starting A high performanc… and a reverse proxy server...
         Starting OpenBSD Secure Shell server...
         Starting Permit User Sessions...
[  OK  ] Started User Login Manage
[  OK  ] Finished Permit User Sessions.
[  OK  ] Started Getty on tty1.
[  OK  ] Started Modem Manager.
[  OK  ] Started OpenBSD Secure Shell server.
[  OK  ] Started A high performance…er and a reverse proxy server.
[  OK  ] Started Hostname Service.
         Starting Network Manager Script Dispatcher Service...
[  OK  ] Started Network Manager Script Dispatcher Service.
[  OK  ] Created slice system-systemd\x2dbacklight.slice.
[   32.935276] stm32-rproc 10000000.m4: wdg irq registered
[   32.941476] remoteproc remoteproc0: m4 is available
[   32.958564] [drm:drm_bridge_attach] *ERROR* failed to attach bridge /soc/dsi@5a000000 to encoder DPI-31: -517
         Starting Load/Save Screen …f backlight:panel-backlight...
[  OK  ] Finished Load/Save Screen … of backlight:panel-backlight.
[   33.177508] [drm:drm_bridge_attach] *ERROR* failed to attach bridge /soc/dsi@5a000000 to encoder DPI-31: -517
[  OK  ] Found device /dev/ttySTM0.
[  OK  ] Started Serial Getty on ttySTM0.
[  OK  ] Reached target Login Prompts.
[  OK  ] Reached target Multi-User System.
[  OK  ] Reached target Graphical Interface.
         Starting Update UTMP about System Runlevel Changes...
[  OK  ] Finished Update UTMP about System Runlevel Changes.
[   33.651687] dwc2 49000000.usb-otg: supply vusb_d not found, using dummy regulator
[   33.684404] dwc2 49000000.usb-otg: supply vusb_a not found, using dummy regulator
[   33.826043] dwc2 49000000.usb-otg: EPs: 9, dedicated fifos, 952 entries in SPRAM
[   33.860157] dwc2 49000000.usb-otg: DWC OTG Controller
[   33.870075] dwc2 49000000.usb-otg: new USB bus registered, assigned bus number 2
[   33.906169] dwc2 49000000.usb-otg: irq 51, io mem 0x49000000
[   33.926645] usb usb2: New USB device found, idVendor=1d6b, idProduct=0002, bcdDevice= 5.15
[   33.953543] usb usb2: New USB device strings: Mfr=3, Product=2, SerialNumber=1
[   33.969347] usb usb2: Product: DWC OTG Controller
[   33.982103] usb usb2: Manufacturer: Linux 5.15.65-armv7-lpae-x30 dwc2_hsotg
[   33.996095] usb usb2: SerialNumber: 49000000.usb-otg
[   34.007656] hub 2-0:1.0: USB hub found
[   34.018201] hub 2-0:1.0: 1 port detected
[   34.040081] [drm:drm_bridge_attach] *ERROR* failed to attach bridge /soc/dsi@5a000000 to encoder DPI-31: -517
[   34.059224] [drm:drm_bridge_attach] *ERROR* failed to attach bridge /soc/dsi@5a000000 to encoder DPI-31: -517
 
Debian GNU/Linux 11 arm ttySTM0
 
default username:password is [debian:temppwd]
 
arm login: [   36.392709] stm32-dwmac 5800a000.ethernet eth0: PHY [stmmac-0:00] driver [RTL8211E Gigabit Ethernet] (irq=POLL)
[   36.411191] stm32-dwmac 5800a000.ethernet eth0: Register MEM_TYPE_PAGE_POOL RxQ-0
[   36.425124] dwmac4: Master AXI performs any burst length
[   36.434808] stm32-dwmac 5800a000.ethernet eth0: No Safety Features support found
[   36.658599] stm32-dwmac 5800a000.ethernet eth0: IEEE 1588-2008 Advanced Timestamp supported
[   36.670724] stm32-dwmac 5800a000.ethernet eth0: registered PTP clock
[   36.676992] stm32-dwmac 5800a000.ethernet eth0: configuring for phy/rgmii-id link mode
[   40.780334] stm32-dwmac 5800a000.ethernet eth0: Link is Up - 1Gbps/Full - flow control rx/tx
[   40.787539] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
[   41.015597] [drm:drm_bridge_attach] *ERROR* failed to attach bridge /soc/dsi@5a000000 to encoder DPI-31: -517
[   41.044836] [drm:drm_bridge_attach] *ERROR* failed to attach bridge /soc/dsi@5a000000 to encoder DPI-31: -517
[   43.278419] [drm:drm_bridge_attach] *ERROR* failed to attach bridge /soc/dsi@5a000000 to encoder DPI-31: -517
[   43.353221] spi-nor spi0.0: mx66l51235f (65536 Kbytes)
[   43.386430] input: pmic_onkey as /devices/platform/soc/5c002000.i2c/i2c-2/2-0033/5c002000.i2c:stpmic@33:onkey/input/input0
[   43.425684] [drm:drm_bridge_attach] *ERROR* failed to attach bridge /soc/dsi@5a000000 to encoder DPI-31: -517
[   43.503909] [drm:drm_bridge_attach] *ERROR* failed to attach bridge /soc/dsi@5a000000 to encoder DPI-31: -517
[   43.538977] spi-nor spi0.1: mx66l51235f (65536 Kbytes)
[   43.615948] [drm:drm_bridge_attach] *ERROR* failed to attach bridge /soc/dsi@5a000000 to encoder DPI-31: -517
[   44.201364] input: Microsoft Microsoft 3-Button Mouse with IntelliEye(TM) as /devices/platform/soc/5800d000.usb/usb1/1-1/1
[   44.292375] hid-generic 0003:045E:0040.0001: input,hidraw0: USB HID v1.10 Mouse [Microsoft Microsoft 3-Button Mouse with 0
[   44.343737] [drm:drm_bridge_attach] *ERROR* failed to attach bridge /soc/dsi@5a000000 to encoder DPI-31: -517
[   44.379708] input: DELL Dell USB Entry Keyboard as /devices/platform/soc/5800d000.usb/usb1/1-1/1-1.3/1-1.3:1.0/0003:413C:2
[   44.479567] hid-generic 0003:413C:2107.0002: input,hidraw1: USB HID v1.11 Keyboard [DELL Dell USB Entry Keyboard] on usb-0
[   44.498558] [drm:drm_bridge_attach] *ERROR* failed to attach bridge /soc/dsi@5a000000 to encoder DPI-31: -517'

1 ACCEPTED SOLUTION

Accepted Solutions
isca-dim
Associate II

Ok guys,

I found the answer. It was an unfortunate default configuration in minicom. press Ctrl+A and O to go to mincom's configuration -> serial port setup and disable Hardware Flow Control.

That fixes the output-only problem of UART but I still don't get any output with ST-LINK.

View solution in original post

7 REPLIES 7
isca-dim
Associate II

Ok guys,

I found the answer. It was an unfortunate default configuration in minicom. press Ctrl+A and O to go to mincom's configuration -> serial port setup and disable Hardware Flow Control.

That fixes the output-only problem of UART but I still don't get any output with ST-LINK.

PatrickF
ST Employee

Hi,

Did you set the JP4 and JP5 ?

Please refer to https://www.st.com/resource/en/user_manual/um2648-evaluation-boards-with-increasedfrequency-800-mhz-stm32mp157-mpus-stmicroelectronics.pdf

0693W00000Unv0aQAB.pngRegards,

In order to give better visibility on the answered topics, please click on 'Select as Best' on the reply which solved your issue or answered your question. See also 'Best Answers'

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Hello,

Yes the JPs are set and LD6 lights green. Like i mentioned in my post I am able to get the ST-LINK S/N from the CubeIDE Debugger, also the entry shows up on my system on /dev/ttyACM0.

I'm thinking it may be an issue with minicom like it was for the UART.

Hi,

https://wiki.st.com/stm32mpu/wiki/How_to_get_Terminal

classic pitfalls are :

  • miss to set right baud-rate on terminal SW (here it should be 115200,n,8,1)
  • miss to change onwership of Windows COM port to the Linux Virtual Machine tty

maybe try anther terminal SW (e.g. putty) and/or salso try on a Windows PC

Regards.

In order to give better visibility on the answered topics, please click on 'Accept as Solution' on the reply which solved your issue or answered your question.

I have already tried switching to all baud rates of minicom. Here i am inserting the current setup (via UART). The par/bits were 8n1 by default.

I work exclusively from linux pc and I can also connect via ssh without a problem. Only ST-Link has an issue. I have also tried the USBs of other STM boards.

0693W00000Uo06iQAB.png

DYenEmbedded
Associate III

On host PC, Ubuntu 20.04, STM32MP157C-DK2 serial port shows up as /dev/ttyACM0 which when setup as stty -a -G 115200 -echo -icanon -onlcr

It is 8N1, shows the bootup just fine leaving you at prompt for root. My board has the touchscreen,

then the Wayland Terminal is /dev/pts/0 but there is also /dev/ttySTM0 on the board. Serial console is through the ST-LINK microUSB connector. Running the StarterPackage,

ST OpenSTLinux - Weston - (A Yocto Project Based Distro) 4.0.4-openstlinux-5.15-yocto-kirkstone-mp1-v22.11.23 stm32mp1 ttySTM0

Best wishes.

Hi,

never hard of STLINK UART issue unless internal FW were corrupted by some misprogramming.

You might need to check signals presence on JP4 and JP5 (which are used to route UART4 to either Motherboard or STLINK)

You could even try to loop STLINK RX and TX on JP4/JP5 to tests or use an external UART<->USB transceiver on JP4/JP5 (or an STLINKV3-SET)

0693W00000Y8myVQAR.pngRegards,

In order to give better visibility on the answered topics, please click on 'Accept as Solution' on the reply which solved your issue or answered your question.