On 18/02/16 10:45, Arnd Bergmann wrote:

On Thursday 18 February 2016 10:11:37 Vladimir Murzin wrote:

quoted

Right, I thought in a wrong way, in opposite it makes more sense now.

.dtsi

/* below the soc/ */
smb {
        compatible = "simple-bus";
        #address-cells = <2>;
        #size-cells = <1>;
        ranges = <0 0 0x40200000 0x10000>,
                 <1 0 0xa0000000 0x10000>;
};

That looks good, yes.

Is 0x10000 the correct maximum addressable size of the external bus
in both cases?

Intuitively, I would guess that the 0xa0000000 range might
be much wider.

There is only Ethernet connected to this bus (apart from PSRAM), so it
might be wider, but there is no indication of this in documentation.

quoted

.dts

smb {
        ethernet@0,0 {
                compatible = "smsc,lan9220", "smsc,lan9115";
                reg = <0 0x0 0x10000>;
                interrupts = <13>;
                interrupt-parent = <&nvic>;
                smsc,irq-active-high;
};


and looking again at .dtsi it seems to me that fpgaio should be moved
below the soc/ under separate bus interface which would hosts audio and
spi too or I keep missing things around device-tree?

I don't see the audio and spi nodes, so I'm not sure where exactly
you would put them.

I just keep things simple ;)

Ideally those things should be visible from a block diagram in the
datasheet.

Indeed, block diagram indicates all them as a "FPGA APB subsystem" and
clearly draws a line indicating a bus those devices are connected to.
After your point about lan9220, it looks clearer to me to express that
subsystem outside of soc/ node indicating bus interface, so it would
match to those drawings closely.

Cheers
Vladimir

	Arnd