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 for linuxppc-dev@lists.ozlabs.org; Tue, 17 May 2016 08:45:56 -0400
Date: Tue, 17 May 2016 08:43:46 -0400 (EDT)
From: "Robert P. J. Day" <rpjday@crashcourse.ca>
To: Linux PPC Mailing List <linuxppc-dev@lists.ozlabs.org>
Subject: for muram in DTS file, why change #address-cells from <1> to <2>?
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  currently working on a project involving MPC8360 board, and was
handed a patch to the system .dts file that contained the following
snippet for the muram node:

                muram@10000 {
-                       #address-cells = <1>;
+                       #address-cells = <2>;
                        #size-cells = <1>;
                        compatible = "fsl,qe-muram", "fsl,cpm-muram";
-                       ranges = <0 0x10000 0xc000>;
+                       ranges = <0 0 0x10000 0xc000>;

                        data-only@0 {
                                compatible = "fsl,qe-muram-data","fsl,cpm-muram-data";
-                               reg = <0 0xc000>;
+                               reg = <0 0x4000 0x4000>, <0 0x9400 0x1c00>;
                        };

                };

  i'm not a .dts file expert, but i'm baffled by the change in the
value of #address-cells. how does that make any sense? it seems to me
that that kind of change is a *really* fundamental change in the
specification of the underlying architecture.

  can someone explain what that might mean? thanks.

rday

-- 

========================================================================
Robert P. J. Day                                 Ottawa, Ontario, CANADA
                        http://crashcourse.ca

Twitter:                                       http://twitter.com/rpjday
LinkedIn:                               http://ca.linkedin.com/in/rpjday
========================================================================