CPU MX8MP with 8G DDR

[hankwang]

Hi, I have a question about DDR.  Can we know if the uboot can support 8G DDR Size?

As far as I know , if there is 32bit address limitation?  Does DDR maximum only support 3G + 4G size? 

[Chavira]

Hi @hankwang!

Thank you for contacting NXP support!

The iMX8MP can support 8GB.

You must use the DDR tool to regenerate new DDR script for 8GB memory at first. With the new timing file, you can apply your patch to work for 8GB memory size.

i.MX 8M Family DDR Tool Release - NXP Community

After that, set PHY_SDRAM_SIZE to 0xC0000000 and PHY_SDRAM_2_SIZE to 0x140000000 (include/configs/imx8mp_evk.h)

Best Regards!

Chavira

[hankwang]

Hey @Chavira , Thanks for your reply.

Does Uboot support 8G DDR? Because our nxp agent told me that there is a 32-bit address limit in Uboot. Therefore, 8MP supports up to 3G+4G size.

I wonder if NXP tested the 8G DDR on the 8MP EVK board? As far as I know, NXP EVK board can change different DDR sizes in NXP.

[Chavira · Accepted solution]

Hi @hankwang!

U-boot doesn't have this limitation that you mention.

We only have 6 GB on EVK, but some boards like Variscite boards have 8GB of RAM using iMX8MP

Sorry for the mistake!

Best Regards!
Chavira

[hankwang]

Hey @Chavira Thanks for the information. Do you know  which Variscite boards  have 8GB RAM using iMX8MP? Because I cannot find this board?

[Chavira]

Hi @hankwang!

I am talking about "VAR-SOM-MX8M-PLUS".
You can download their datasheet by following the link:

https://www.variscite.com/wp-content/uploads/2020/10/VAR-SOM-MX8M-PLUS_Datasheet.pdf

If you need more information about the board please contact Variscite support!

Best Regards!
Chavira

[hankwang]

@Chavira  I got it. Thank you for the information.