What is a DCD ?

[shaik4co...@gmail.com]

I just wanted to understand what is Device Configuration Data (DCD); where shall find one for wandboard or any other board.

Thanks in advance.

[Michał Ściubidło]

> I just wanted to understand what is Device Configuration Data (DCD);
> where shall find one for wandboard or any other board.

It's way to configure SOC. It's explained in Reference Manual. You can
find some in uboot/board/boundary/nitrogen6x

[Mike Jones]

I noticed that the memory used on the Wandboard is the same as the nitrogen6x. Has anyone tuned the DCD for the Wandboard memory layout or have people been using the nitrogen6x DCD?

I am not a linux guy and work with the Freescale SDK, so I don't know how to find out what DCD info is used in the Linux image. Can someone point me to where in the Linux source tree the DCD data comes from for the Wandboard?

For the original author, the i.MX 6Dual/Quad Applications Processor Reference Manual on the Freescale site explains the DCD. When I use the SDK on a Sabre SD board, I use this data in my Eclipse debug configuration. It basically sets up the memory manager and memory timing so that the JTAG than then successfully download an elf file and debug it. When booting from SD, the DCD data is in the image structure, also described in the reference manual. The instructions for building a Linux image for the Sabre SD board has more details.

[Fabio Estevam]

On Sat, Oct 5, 2013 at 5:34 PM, Mike Jones <proc...@gmail.com> wrote:
> I noticed that the memory used on the Wandboard is the same as the
> nitrogen6x. Has anyone tuned the DCD for the Wandboard memory layout or have
> people been using the nitrogen6x DCD?

In mainline U-boot the DDR initialization for wandboard is the same
for nitrogen.

>
> I am not a linux guy and work with the Freescale SDK, so I don't know how to
> find out what DCD info is used in the Linux image. Can someone point me to
> where in the Linux source tree the DCD data comes from for the Wandboard?

Kernel does not touch DCD data. It is U-boot that provides the DCD
configuration.

Regards,

Fabio Estevam