imx6ull-14x14-evk access to more than 512MB DRAM

[BillJ]

Hi, my apologies if this should be obvious to me, but I am working with an imx6ull EVK board that is supposed to have a 4GB DRAM chip according to the datasheet for it. When I boot it up with the micro SD card provided, both u-boot and the linux kernel only report 512MB of RAM. What am I missing in order for linux to have access to more than the 512MB of RAM?

[turker · Accepted solution]

I do not think that the i.MX6ULL EVK from NXP has 4GB RAM. It is probably 4Gbit which is 512MB. You can search for the part number of the memory chip on the carrier module to make sure.

[BillJ]

Hi Turker, thank you for your response. The EVK data sheet link reads "4GB" but it appears that you are correct that the SDRAM part is "4Gb" in size which, as you say, is 512MB. I appreciate you pointing that out. 

[BillJ]

Hi Igor,

Thank you for the response. I went ahead and created a patch and an associated bbappend file using the meta-fsl-bsp-release layer and confirmed that the u-boot source file (mx6ullevk.h) was patched so that PHYS_SDRAM_SIZE was set to SZ_1G, but I still get the same result. Also, even before attempting the patch, I see a CRC error message from the u-boot start process so I am not sure where the problem lies at the moment. These are the u-boot messages I see:

U-Boot 2017.03-imx_v2017.03_4.9.88_2.0.0_ga+gb76bb1bf9f (Mar 03 2021 - 17:59:47 -0800)
CPU: Freescale i.MX6ULL rev1.1 at 396MHz
CPU: Commercial temperature grade (0C to 95C) at 32C
Reset cause: POR
Model: Freescale i.MX6 ULL 14x14 EVK Board
Board: MX6ULL 14x14 EVK
DRAM: 512 MiB
MMC: FSL_SDHC: 0, FSL_SDHC: 1
*** Warning - bad CRC, using default environment

[igorpadykov]

Hi BillJ

uboot imx_v2017.03 is very old, suggest to try latest described on

https://www.nxp.com/design/software/embedded-software/i-mx-software/embedded-linux-for-i-mx-applicat...

Also had board passed ddr test :

https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/i-MX-6-7-DDR-Stress-Test-Tool/ta-p/11082...

Best regards
igor

[igorpadykov]

Hi BillJ

uboot imx_v2017.03 is very old, suggest to try latest described on

https://www.nxp.com/design/software/embedded-software/i-mx-software/embedded-linux-for-i-mx-applicat...

Also had board passed ddr test :

https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/i-MX-6-7-DDR-Stress-Test-Tool/ta-p/11082...

Best regards
igor

[igorpadykov]

Hi BillJ

one can look at uboot #define PHYS_SDRAM_SIZE :

https://source.codeaurora.org/external/imx/uboot-imx/tree/include/configs/mx6ullevk.h?h=imx_v2020.04...

Best regards
igor