Alternate RAM for STMP157

[gs018]

Hi,

I am building my STMP157 board using the reference of "STMP15X-SOM". In this the RAM used is K4B4G1646D-BYK0, but I am unable to find the part number in online store. Can you please help me in finding the different RAM which can be used instead of it.

[LubOlimex]

Hard to say, even when RAM seems the same it might require slight software tweaks, but maybe K4B4G1646E-BMMA.

[gs018]

Thank you for your reply,

Can you also please help me with the STMP processor, is it STM32MP157CAA OR STM32MP157AAA.

[LubOlimex]

No crypto, STM32MP157A/D.

[gs018]

I have designed the board and is planning to populated the board, can you please suggest if I am going to change the RAM on the board then what are the changes which are needed to be made in the software and where to make the changes and can you please suggest any reference from where I can get the idea.

[LubOlimex]

The software is open source, all sources are available at our GitHub, you'd have to edit the u-boot for the different RAM settings. I can't do it for you. What exactly depends on the RAM but check this guide about links to sources and description of rebuilding:

https://github.com/OLIMEX/OLINUXINO/blob/master/DOCUMENTS/OLIMAGE/Olimage-guide.pdf

[gs018]

Thank you for your reply,

Can you please tell me the which deconfig file to use in the config directory to build the custom u-boot

[LubOlimex]

configs/STM32-OLinuXino-SOM_defconfig

Maybe also check arch/arm/dts/stm32mp1-olinuxino-som.dts and arch/arm/dts/stm32mp1-olinuxino-som-u-boot.dtsi

Also maybe look in the commits:

https://github.com/OLIMEX/u-boot-olinuxino/commits/release-20240312/

[gs018]

Hi,

I went through the stm32-ddr-1x4Gb-binG.dtsi file of the Olimax and I have generated my file from the cubeMX and there were certain parameter which are not present in the generated file such as -

#define DDR_DX0DLLCR 0x40000000
#define DDR_DX0DQTR 0xFFFFFFFF
#define DDR_DX0DQSTR 0x3DB02000
#define DDR_DX1DLLCR 0x40000000
#define DDR_DX1DQTR 0xFFFFFFFF
#define DDR_DX1DQSTR 0x3DB02000
#define DDR_DX2DLLCR 0x40000000
#define DDR_DX2DQTR 0xFFFFFFFF
#define DDR_DX2DQSTR 0x3DB02000
#define DDR_DX3DLLCR 0x40000000
#define DDR_DX3DQTR 0xFFFFFFFF
#define DDR_DX3DQSTR 0x3DB02000

can you please explain why are this used. and is this only parameters which are needed to be change or there are more parameters which are needed to be changed.

[LubOlimex]

Unfortunately, that is all support I can provide for the software. Anything else would require considerable time and effort and this is open source project with all sources available even without purchase.

[gs018]

Hi,

Can you please introduce some one from the software team of yours's who could help me ??

[LubOlimex]

Just look at the contributors at the u-boot-olinuxino and olinuxino-tools projects at the Olimage GitHub projects and contact them over GitHub, I can't promise they'd want to assist you, tho.