[U-Boot-Users] Ideas on U-Boot configuration with FDT

Timur Tabi timur at freescale.com
Fri May 18 17:01:28 CEST 2007

Wolfgang Grandegger wrote:

> RAM is _not_ available at that stage.

Do we really need RAM to parse the device tree and configure U-Boot?  I think not.

The device tree has a memory section:

	memory {
		device_type = "memory";
		reg = <00000000 10000000>;	// 256MB

So the question is: do we want U-Boot to use this node to determine how much RAM there is, 
or do we want U-Boot to determine how much RAM there is and update this node?

> Depends, you might be right for FLASH on a 32-bit bus. On slow ROM 
> devices and slow processors, it matters.

I still don't see how it's important.  If the device tree is on slow memory, so what?  You 
have to read it sooner or later.  If your board can't handle this feature, then don't 
enable it, and configure U-Boot the "old fashioned way".

Timur Tabi
Linux Kernel Developer @ Freescale

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