Re: [PATCH v6 2/2] memory: atmel-ebi: add DT bindings documentation

From: Mark Rutland
Date: Thu Apr 28 2016 - 05:29:49 EST


Hi,

On Thu, Apr 28, 2016 at 08:44:05AM +0200, Boris Brezillon wrote:
> On Wed, 27 Apr 2016 16:07:38 +0100
> Mark Rutland <mark.rutland@xxxxxxx> wrote:
> > On Wed, Apr 27, 2016 at 04:35:54PM +0200, Boris Brezillon wrote:
> > > + ebi: ebi@10000000 {
> > > + compatible = "atmel,sama5d3-ebi", "simple-bus";
> > > + #address-cells = <2>;
> > > + #size-cells = <1>;
> > > + atmel,smc = <&hsmc>;
> > > + atmel,matrix = <&matrix>;
> > > + reg = <0x10000000 0x10000000
> > > + 0x40000000 0x30000000>;
> > > + ranges = <0x0 0x0 0x10000000 0x10000000
> > > + 0x1 0x0 0x40000000 0x10000000
> > > + 0x2 0x0 0x50000000 0x10000000
> > > + 0x3 0x0 0x60000000 0x10000000>;
> > > + clocks = <&mck>;
> > > +
> > > + pinctrl-names = "default";
> > > + pinctrl-0 = <&pinctrl_ebi_addr>;
> > > +
> > > + cs@0 {
> > > + #address-cells = <2>;
> > > + #size-cells = <1>;
> > > + ranges;
> > > + atmel,generic-dev;
> > > + atmel,read-mode = "nrd";
> > > + atmel,write-mode = "nwe";
> > > + atmel,bus-width = <16>;
> > > + atmel,ncs-rd-setup-ns = <0>;
> > > + atmel,ncs-wr-setup-ns = <0>;
> > > + atmel,nwe-setup-ns = <8>;
> > > + atmel,nrd-setup-ns = <16>;
> > > + atmel,ncs-rd-pulse-ns = <84>;
> > > + atmel,ncs-wr-pulse-ns = <84>;
> > > + atmel,nrd-pulse-ns = <76>;
> > > + atmel,nwe-pulse-ns = <76>;
> > > + atmel,nrd-cycle-ns = <107>;
> > > + atmel,nwe-cycle-ns = <84>;
> > > + atmel,tdf-ns = <16>;
> > > +
> > > + nor: flash@0,0 {
> > > + compatible = "cfi-flash";
> > > + #address-cells = <1>;
> > > + #size-cells = <1>;
> > > + reg = <0x0 0x0 0x1000000>;
> >
> > It feels odd that in the node for chipselect N, sub-devices have to
> > encode the chipselect number in their reg, when it's obvious from their
> > container. It may make more sense for the cs node to have a non-empty
> > reg (or somehow to make that translation/truncation implicit).
>
> Would you agree with the following representation?
>
> ebi: ebi@10000000 {
> compatible = "atmel,sama5d3-ebi";
> #address-cells = <2>;
> #size-cells = <1>;
> atmel,smc = <&hsmc>;
> atmel,matrix = <&matrix>;
> reg = <0x10000000 0x10000000
> 0x40000000 0x30000000>;
> ranges = <0x0 0x0 0x10000000 0x10000000
> 0x1 0x0 0x40000000 0x10000000
> 0x2 0x0 0x50000000 0x10000000
> 0x3 0x0 0x60000000 0x10000000>;
> clocks = <&mck>;
>
> pinctrl-names = "default";
> pinctrl-0 = <&pinctrl_ebi_addr>;
>
> configs {
> config-0 {
> atmel,read-mode = "nrd";
> atmel,write-mode = "nwe";
> atmel,bus-width = <16>;
> atmel,ncs-rd-setup-ns = <0>;
> atmel,ncs-wr-setup-ns = <0>;
> atmel,nwe-setup-ns = <8>;
> atmel,nrd-setup-ns = <16>;
> atmel,ncs-rd-pulse-ns = <84>;
> atmel,ncs-wr-pulse-ns = <84>;
> atmel,nrd-pulse-ns = <76>;
> atmel,nwe-pulse-ns = <76>;
> atmel,nrd-cycle-ns = <107>;
> atmel,nwe-cycle-ns = <84>;
> atmel,tdf-ns = <16>;
> };
> };
>
> nor: flash@0,0 {
> compatible = "cfi-flash";
> #address-cells = <1>;
> #size-cells = <1>;
> reg = <0x0 0x0 0x1000000>;
> bank-width = <2>;
> };
> };

Something of that sort looks good to me, yes.

Thanks,
Mark.