[RFC 1/7] soc: qcom: Add device tree binding for SMEM

Bjorn Andersson bjorn.andersson at sonymobile.com
Tue Sep 30 13:00:53 PDT 2014


On Tue 30 Sep 12:03 PDT 2014, Stephen Boyd wrote:

> On 09/29/14 17:34, Bjorn Andersson wrote:
> > +
> > +- reg:
> > +	Usage: required
> > +	Value type: <prop-encoded-array>
> > +	Definition: base address and size pair for each area representing the
> > +		    shared memory. The first pair will must represent the "main"
> > +		    area, where the shared memory header and table-of-content
> > +		    can be found.
> >
> > +
> > += EXAMPLE
> > +
> > +        smem: smem at fa00000 {
> > +                compatible = "qcom,smem";
> > +                reg = <0x0fa00000 0x200000>,
> > +                      <0xfc428000 0x4000>;
> 
> Isn't this second entry rpm message ram? That isn't the same as smem.
> Plus smem is part of ram (and rpm message ram is not) so we need to do
> memory reservations or something.
> 

Correct they are different, but smem covers both of those and allocations are
only supposed to be done in the first of these.

And I forgot to mention that I have the following in my dt:

/ {
        reserved-memory {
                #address-cells = <1>;
                #size-cells = <1>;
                ranges;

                smem at fa00000 {
                        #memory-region-cells = <0>;
                        reg = <0x0fa00000 0x200000>;
                        no-map;
                };
        };
};

Regards,
Bjorn



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