Supporting 512 MB DDR SDRAM for AM3715

Have you looked at http://processors.wiki.ti.com/index.php/Setting_up_AM37x_SDRC_registers

Regards,

Vaibhav

Dear Vaibhav,

Thank you for the reply.

I am setting this registers for CS0 and CS1 and able to detect the 512 MB of size after reading SDRC_CS_CFG. x-loader loads the u-boot and s_init is also successful where we initialize the clocks, gpios and memory. In mem_init there is a early initialization for CS0 bank and I have added a code for initializing CS1 too here but even though start_armboot() function never gets called.

Could you please let me know what am I missing? any more changes are needed? any suggestions?

Thanks,

-Ninad.

Hi,

SDRAM init is handled by the x-loader only. You can refer to the function make_cs1_contiguous() under "board/omap3evm/omap3evm.c" in the x-loader sources for using two chip selects. This enables a stacked configuration of 256MB with each CS having 128MB and you could use this as a reference.

Note that U-Boot SDRAM code is never executed as U-Boot is already running for RAM. The SDRAM code in U-Boot is present there just for the sake of completion. So any SDRAM issues that you might face would need to be in x-loader.

Regards,

Vaibhav

Dear Vaibhav,

You are right, mem_init never gets called in u-boot because its already in RAM.

And yes I did chnage the make_cs1_contiguous() code for considering the configuration of 512MB with each CS having 256MB and now all the SDRC registers seems proper. But  results are same as I posted earlier.

Thanks,

-Ninad.