AM5716: UART boot issue

Sooraj KS

Part Number: AM5716

Hi,

I am trying to load SPL and uboot through UART interface to a custom board with Sitara AM5716.

I successfully tested it in AM335x EVM. When I power on this board I could see ASCII character 'C' continuously receiving on UART console from boot ROM and it accepted SPL when sent it using xmodem protocol. After that I could load uboot using ymodem protocol.

But in AM5716 processor, ASCII character 'C' is not receiving from boot ROM. Instead, some invalid ASCII characters are receiving. Also, it is not accepting SPL through UART when sent it using xmodem protocol.

I could find some threads in TI E2E Community discussing the same issue and the solution detailed in these threads is to use a perl script to load SPL and use ymodem protocol to load uboot image after that. I tried the steps detailed in these threads, but failed.

How can I load SPL in the board with AM5716?

If the procedure to load SPL in AM5716 is not same as that of AM335x, where I can find the details?

Please help.

Thanks and Regards,

Sooraj

over 8 years ago

0 Biser Gatchev-XID over 8 years ago

TI__Guru**** 393215 points

No, AM57x UART boot procedure is different from AM335x. See e2e.ti.com/.../549800 for details.

0 Sooraj KS over 8 years ago in reply to Biser Gatchev-XID

Prodigy 130 points

Thank you Biser.

I went through the discussion in the link you provided, after that we could download SPL using the perl script. (It is showing that the SPL load is completed). But couldn't load u-boot.img.

As per the steps detailed in the pdf from the link (e2e.ti.com/.../AM57_5F00_UART_5F00_Boot_5F00_SOP_5F00_By_5F00_TI_5F00_Rio_5F00_Final.pdf), I should be able to see prints 'CCC' on the console after sending SPL and sending u-boot.img using y modem protocol should work.

But the print is not coming and it is not accepting u-boot.img.

UART configuration we tried are 115200 8N1 and 115200 8E1. We tried both pre built images got from AM57xx SDK and ones build by our self from the u-boot source code in in the SDK.

Could you verify that our settings are correct or not ?

We followed the building process mentioned in the webpage under the link processors.wiki.ti.com/.../Linux_Core_U-Boot_User's_Guide

While building u-boot the build configuration we used is 'am57xx_evm_defconfig'. We noticed that the build configuration for UART boot for AM571x IDK is left blank in the table showing the default build configuration for different boards(please check the attached screenshot).

Ours is a not a copy of AM571x IDK but a custom board with AM5716 SoC. There is no change in the peripherals needed for u-boot to load. Could you confirm that the configuration 'am57xx_evm_defconfig' is the one for AM571x IDK UART boot too?

Could you suggest anything else we can try to solve this issue ?

Thanks,

Sooraj

0 Biser Gatchev-XID over 8 years ago in reply to Sooraj KS

TI__Guru**** 393215 points

Have you done the EMIF configuration, as described here: www.ti.com/.../sprac36a.pdf

0 Sooraj KS over 8 years ago in reply to Biser Gatchev-XID

Prodigy 130 points

Thank you Biser,

I am going through it.

I was studying the boot process, could you give the file name from which the SPL send console print 'CCC'?

I will try EMIF configuration inform you.

Thanks,
Sooraj

0 Kemal R. Shakir over 8 years ago in reply to Sooraj KS

TI__Guru 55345 points

The 'CCC' comes from the ROM code. On successfully load of SPL you should not see any 'CCC'.

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AM5716: UART boot issue