device tree question

Scott Wood scottwood at freescale.com
Wed Sep 19 08:06:06 EST 2007


Alan Bennett wrote:
> I want to make the mpc8272ads.dts tree work for my board.
> 
> I have an mpc8248
>   128MB Flash@ f800_0000  (Spansion S29GL512N)
>   128MB Flash@ D000_0000  (Spansion S29GL512N)
>   BCSR at e400_0000
>   2nd CSR at e410_0000
>   RAM at e420_0000
>   128MB SDRAM@[0x0..0800_0000]

What chip selects are all of these things on, and what are the 
base/length of each chip select?

> 
> Is it ok to have 0 in these:
> 	cpus {
> 		PowerPC,8272 at 0 {
>          . . .
> 			timebase-frequency = <0>;
> 			bus-frequency = <0>;
> 			clock-frequency = <0>;
>         . . .

Yes, the bootwrapper will fill in the proper values.

> How do I modify the following lines to match my hardware?
> 
> 	localbus at f0010100 {
>       . . .
> 		ranges = <0 0 fe000000 02000000
> 		          1 0 f4500000 00008000
> 		          3 0 f8200000 00008000>;

Put your chip select mappings here.

> 		flash at 0,0 {
> 			compatible = "jedec-flash";
> 			reg = <0 0 2000000>;
> 			bank-width = <4>;
> 			device-width = <1>;
> 		};
> 
> 		board-control at 1,0 {
> 			reg = <1 0 20>;
> 			compatible = "fsl,mpc8272ads-bcsr";
> 		};

Put your chip select devices here.

-Scott


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