EMIF register configuration for MT41K256M16HA-125:E on AM437x

Arun Bharadwaj

Hi,

I am trying to bring up a custom board having an AM437x processor and DDR3 RAM with part number MT41K256M16HA-125:E with a 16-bit width. I am trying to configure the EMIF registers in u-boot by using the AM43xx DDR Calculation Tool provided here: http://processors.wiki.ti.com/index.php/AM437x_DDR_Configuration_and_Programming_Guide

Due to the difference in DDR3 width, I cannot directly reuse the register values used by the AM437x-EVM.

It seems like I am not able to get past the SDRAM initialization part in u-boot code and my console hangs before/during the code relocation happens. Any pointers regarding how to configure the EMIF registers would be very helpful.

Thanks,

Arun

over 9 years ago

0 Biser Gatchev-XID over 9 years ago

TI__Guru**** 393215 points

Hi,

Have you set EMIF4D_SDRAM_CONFIG bitfield NARROW_MODE to 1?

0 JJD over 9 years ago in reply to Biser Gatchev-XID

TI__Guru* 86180 points

Check the description on wiki. Need to change 2 different registers to support 16-bit mode:

NARROW_MODE - AM437x supports both 16-bit (NARROW_MODE=1) and 32-bit (NARROW_MODE=0) data bus. This value should be the same as CTRL_SDRAM_CONFIG_EXT.NARROW_ONLY. NARROW_MODE controls the mode of the EMIF controller, whereas NARROW_ONLY controls the DDR PHY.

Regards,
James

0 Arun Bharadwaj over 9 years ago in reply to JJD

Prodigy 60 points

Thanks for your replies. NARROW_MODE was already set to 1. I did set the NARROW_ONLY also to 1 but with no improvements.

Regards,
Arun

0 JJD over 9 years ago in reply to Arun Bharadwaj

TI__Guru* 86180 points

Arun, do you have the ability to connect through JTAG to your custom board? I'd like to try with a low level GEL file to get your SDRAM functional to avoid issues with u-boot. BTW, which revision of u-boot (or SDK) are you using?

regards,
James

0 Arun Bharadwaj over 9 years ago in reply to JJD

Prodigy 60 points

Hi James,

I managed to get past the issue by faking the board_name as AM43__SK since we seem to have very similar RAM configuration (except the narrow mode). Thanks for your help.

regards,
Arun

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EMIF register configuration for MT41K256M16HA-125:E on AM437x