How to configure the DRAM

[shanmugamsundar]

Hi all,

I am using IMX6dual processor with 512 MB ddr3  chip MT41K128M16JT-125 for our customized board, how to configure the DDR parameters in u-boot, for 512 mb size, 32 bit bus width and chip select 0,

On my understanding i configured these settings in the file called flash_header.s in mx6q_sabrelite folder by modifying the register MXC_DCD_ITEM(75, MMDC_P0_BASE_ADDR + 0x000, 0x83190000) , is it enough to configure the DDR or i need to configure these in some where else?

RAM:

For the RAM size i configured in the file called    include/configs/mx6q_sabrelite_android.h

// #define PHYS_SDRAM_1_SIZE     (1u * 1024 * 1024 * 1024) orignal for 1gb

#define PHYS_SDRAM_1_SIZE       (1u * 512 * 1024 * 1024)  this is what i modified for 512 mb

NOTE:

And for DDR DCD configuration, i modified the DCD registers with the reference of init script,  which get success for our DDR ram by DDR TEST TOOL

SD CARD:

And for enabling the SD boot , i changed in the same file  include/configs/mx6q_sabrelite_android.h

#define CONFIG_FSL_ENV_IN_MMC   ---> i enabled this in the file

/* #define CONFIG_FSL_ENV_IN_SATA */

// #define CONFIG_FSL_ENV_IN_SF -----> orignal

We are using SD3 slot, for that i changed the corresponding MUX pin settings in the file board/freescale/mx6q_sabrelite/mx6q_sabrelite.c

Is the above settings is ok for enabling the SD boot and DDR configuration or any extra settings needed kindly plz guide me with any suggestion

For your reference herewith i have attached my flash_header.S file kindly find the attachment

Original Attachment has been moved to: flash_header.S.txt.zip

[alejandrolozan1]

Hi,

As far as I understand you want to boot from the SD, correct?

As you might know the iMX6 features a  boot ROM code that uses fuses, and GPIO settings to determined the boot device like SD, SPI, NAND, USB, etc.

But the boot flow of the ROM code is not determined by the generated image. Then the configuration to boot from SD is not really necessary.

In regards the DCD; this is a set of commands that the ROM code uses to configure certain modules like the DDR. The DCD table should be generated with the bootable image like U-Boot.

And you need to change this DCD table according to your DDR settings. I recommend you to check and use as reference the u-boot source code that fits the more to your DDR configuration (SABRE-SD, SABRE-AI).

Best Regards,

Alejandro