AM69: UART bootloader

The problem：The serial port has no output

Hi,

Do you see ping from ROM (Character 'c' printing on the console) after powering up the board in UART boot mode?

Regards,
Parth

The serial  port has no input at all

Hi Ming,

First thing that you should I serve on the uart is the character C repeating on the console. Also you have to start with tiboot3.bin and not the u-boot-spl.bin.

Best Regards,

Keerthy 

I have understood and have made certain progress on top of this thanks.

Current Progress and Issues with UART Booting

Setup Details:

1. PC Serial Ports:

• My PC serial port is ttyUSB1-4
• According to Table 2-4 in spruj70a.pdf (ti.com)
  • ttyUSB2 corresponds to MCU_UART
  • ttyUSB3 corresponds to UART8 (used for A72 debug)

2. Boot Flows

• Following section 3.1.1.1.4 in 3.1.1.1. General Information — Processor SDK Linux for AM69 Documentation
  • MCU R5 handles two files: tiboot3.bin and tispl.bin
  • A72 handles one file: u-boot.img
• This suggests three files need to be sent via the serial port:
  • tiboot3.bin and tispl.bin via ttyUSB2
  • u-boot.img via ttyUSB3

However, section 3.1.1.9 in 3.1.1.9. UART — Processor SDK Linux for AM69 Documentation indicates using only two files( tiboot3.bin and u-boot.img)and the same serial port

Observed Behavior:

1. Sending tiboot3.bin via ttyUSB2, Transfer completes successfully

$ stty -F /dev/ttyUSB2 speed 115200 cs8 -parenb -cstopb
115200
$ sx -kb tiboot3.bin < /dev/ttyUSB2 > /dev/ttyUSB2
Sending tiboot3.bin, 4061 blocks: Give your local XMODEM receive command now.
Bytes Sent: 519936   BPS:10509                           

Transfer complete

and ttyUSB3 prints

U-Boot SPL 2023.04-gb0d868ee08 (Nov 02 2023 - 22:53:54 +0000)
EEPROM not available at 0x50, trying to read at 0x51
SYSFW ABI: 3.1 (firmware rev 0x0009 '9.1.2--v09.01.02 (Kool )
SPL initial stack usage: 13424 bytes
Trying to boot from UART
CCCCCCCCC

2. Sending u-boot.img via ttyUSB2

sx -kb --ymodem u-boot.img < /dev/ttyUSB2 > /dev/ttyUSB2
Retry 0: Timeout on pathname

Transfer incomplete

and ttyUSB3 output is as follows, failed

U-Boot SPL 2023.04-gb0d868ee08 (Nov 02 2023 - 22:53:54 +0000)
EEPROM not available at 0x50, trying to read at 0x51
SYSFW ABI: 3.1 (firmware rev 0x0009 '9.1.2--v09.01.02 (Kool )
SPL initial stack usage: 13424 bytes
Trying to boot from UART
CCCCCCCCCCspl: ymodem err - Timed out
SPL: failed to boot from all boot devices
### ERROR ### Please RESET the board ###

Questions:

• Should u-boot.img be sent to ttyUSB3?
• Should tispl.bin be sent instead?

Attempted Approaches:

1. Sending u-boot.img via ttyUSB3

I shut down ttyUSB3 in minicom and attempted to send the u-boot.img to ttyUSB3, but the transfer failed. When I reopened ttyUSB3 in minicom, there was no response.

$ sx -kb --ymodem u-boot.img < /dev/ttyUSB3 > /dev/ttyUSB3
Sending: u-boot.img
Ymodem sectors/kbytes sent:   1/ 0kRetry 0: Got 61 for sector ACK
Retry 0: NAK on sector
Retry 0: Got 6f for sector ACK
Retry 0: NAK on sector
Retry 0: Got 4f for sector ACK
Retry 0: NAK on sector
Retry 0: Got 5f for sector ACK
Retry 0: NAK on sector
Bytes Sent:1326464   BPS:10017                           
Sending: 
Ymodem sectors/kbytes sent:   0/ 0k
Transfer complete

2. Sending  tispl.bin via ttyUSB2, transfer failure

$ sx -kb tispl.bin < /dev/ttyUSB2 > /dev/ttyUSB2
Sending tispl.bin, 8423 blocks: Give your local XMODEM receive command now.
Xmodem sectors/kbytes sent:   0/ 0kRetry 0: Timeout on sector ACK
Retry 0: Timeout on sector ACK
Retry 0: Timeout on sector ACK

I would greatly appreciate your assistance with this issue. Thank you very much for your help.

I have solved this problem, and your comments were very helpful. Thank you very much!