Linux/AM3358: DDR test from SPL

Zee blue

Part Number: AM3358

Tool/software: Linux

Hi,

I am trying to do a DDR(SDRAM) verification in SPL before loading the u-boot in by beagle bone black.I did a memory walk program for running from spl which will traverse from 0x8000000 to 0x9FFFFFFF.But unfortunately there my program failing and u-boot is not loading at all.When I analyse the source and configurations I notice that the spl bss is mapped to sdram in u-boot-spl.lds. When I modified the bss to internal sram code compilation failed .My doubt are

How this is possible even before initializing the DDR ?

Do DDR is initialized from the ROM code itself ?

Is it possible to do a complete DDR test from SPL ?

Please advice

Regards

Zee

over 7 years ago

0 Pavel Botev over 7 years ago

TI__Guru**** 170625 points

Hi Zee,

Do you use AM335x TI PSDK 4.02?

You can make DDR3 test out of u-boot/spl. You can use CCS and JTAG. Check the below pointers for more info:

http://processors.wiki.ti.com/index.php/Common_DDR_Issues

processors.wiki.ti.com/.../Sitara_Linux_Training:_Tuning_the_DDR3_Timings_on_BeagleBoneBlack

processors.wiki.ti.com/index.php/AM335x_Starter_Kit_Diagnostics#DDR3_DMA_Test_Test

Regards,
Pavel

0 Zee blue over 7 years ago in reply to Pavel Botev

Intellectual 320 points

Hi Pavel,
Thanks for the suggestion ..
I am looking for solution where I can do the test from the SPL before loading the u-boot.
CCS with Jtag may not work for us because memory test should go with the production build of SPL/ u-boot

Is there any way to do so ?

Regards
Zee

0 Pavel Botev over 7 years ago in reply to Zee blue

TI__Guru**** 170625 points

Do you use AM335x TI PSDK 4.02?

0 Zee blue over 7 years ago in reply to Pavel Botev

Intellectual 320 points

I am using u-boot version 2017-09

0 Pavel Botev over 7 years ago in reply to Zee blue

TI__Guru**** 170625 points

Zee,

Up to u-boot 2017-01 is supported on AM335x TI devices. I would recommend using that version, you can take it from latest PSDK 4.02.

software-dl.ti.com/.../index_FDS.html

I will have a look at your specific questions regarding SPL DDR3 test and come back to you.

Regards,
Pavel

0 Pavel Botev over 7 years ago

TI__Guru**** 170625 points

Zee blue said:
How this is possible even before initializing the DDR ?

Seems that first DDR is initialized (from SPL/MLO), then BSS in configured in DDR.

u-boot/doc/SPL/README.omap3

Zee blue said:
Do DDR is initialized from the ROM code itself ?

No. You can check what ROM Code does in AM335x TRM.

Zee blue said:
Is it possible to do a complete DDR test from SPL ?

That should be possible. If you remove your u-boot.img from your FAT partition, will your boot flow end up in the SPL command prompt? You can check there what commands you have available.

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Linux/AM3358: DDR test from SPL