AM3352: AM3352 failed to boot from nand_flash

MENGDONG FENG

Part Number: AM3352

I am set AM3355 boot from nand_flash，and i have so many AM3352, but five out of a thousand machines fail,Boot failure can also occur when a machine in normal use is repowered,when problem is hapeen,It won't go back to normal。when problem happened,i read data from nand_flash and compare data from the normal startup machine，it is exactly same。and i see sysboot data ,it is correct

i try to read out nand_flash block0 data and then write it into block0 again,i found boot successful。so i can not understand why this problem happend? and Are there any register that can display information or status during ROM_code start up, e.gcurrent boot mode or device,whether the startup was successful?

over 5 years ago

0 Mark M over 5 years ago

TI__Mastermind 30631 points

Hi,

You read the block0 data and then wrote the data that you read back into block0 and it fixes the boot issue? What writer do you use? Is the writer handling ECC and bad-block management?

Where does the boot fail? Can you get into uBoot on a failing unit before you re-flash the NAND? You may be able to check the NAND flash with the tools available.

Do you have JTAG?

There are the Tracing Vectors available to see each “way point” in the ROM Code execution sequence. See 26.1.14 Tracing in TRM (SPRUH73Q)

Also some threads on the E2E may help

https://e2e.ti.com/support/tools/code-composer-studio-group/ccs/f/code-composer-studio-forum/588239/ccs-am3352-unabled-to-access-to-tracing-vectors

https://e2e.ti.com/support/processors-group/processors/f/processors-forum/894279/am3352-custom-board-boot-issue

Hope this helps,
Mark

0 MENGDONG FENG over 5 years ago in reply to Mark M

Prodigy 180 points

HI ，

You read the block0 data and then wrote the data that you read back into block0 and it fixes the boot issue? What writer do you use? Is the writer handling ECC and bad-block management?

yes,it fuxe then boot issue, i just use JTAG read data and write data by AM3352

Where does the boot fail? Can you get into uBoot on a failing unit before you re-flash the NAND? You may be able to check the NAND flash with the tools available.

i only know AM3352 have found nand_flash,but i do not know where does then boot fail.

i will look Tracing Vectors and try to found reason.

0 MENGDONG FENG over 5 years ago in reply to Mark M

Prodigy 180 points

HI ，

The following figure is the trace vector that I monitored

i aslo monitored normol boot AM3352 ,They're the same

i found word3=0x10020(adress 0x4030CE48), bit5=1,it means Memory booting device MMCSD0。and my sysboot[4:0]=2,so It's impossible boot from MMCSD0.so i can no understand it.

Am I monitoring the wrong variable? or?
can you help to look at the meaning of trace vector which i monitored? TS

0 MENGDONG FENG over 5 years ago in reply to Mark M

Prodigy 180 points

add some information

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AM3352: AM3352 failed to boot from nand_flash