[PATCH v3 2/2] dt-bindings: pcie: Add documentation for Mediatek PCIe

[Ryder Lee]

On Wed, 2017-05-10 at 10:08 +0200, Arnd Bergmann wrote:
> On Wed, May 10, 2017 at 4:07 AM, Ryder Lee <ryder.lee at mediatek.com> wrote:
> 
> > +- ranges:
> > +  - The first three entries are expected to translate the addresses for the root
> > +    port registers, which are referenced by the assigned-addresses property of
> > +    the root port nodes (see below).
> 
> I don't understand this part. Why do you need a static translation for these?
> Shouldn't they just be listed in the 'reg' property of the parent node now that
> you have the clk/reset/phy properties in the parent as well?

At first, I did like that. But I noticed that someone suggest it's
better to use 'assigned-addresses' to handle per-port registers, the
same path as tegra and marvell did, in other platform discussion thread.
So I just put shared register in root node. It could be rolled back if
you feel this is inappropriate.

> > +Required properties:
> > +- device_type: Must be "pci"
> > +- assigned-addresses: Address and size of the port configuration registers
> > +- reg: Only the first four bytes are used to refer to the correct bus number
> > +  and device number.
> > +- #address-cells: Must be 3
> > +- #size-cells: Must be 2
> > +- #interrupt-cells: Must be 1
> > +- interrupt-map-mask and interrupt-map: Standard PCI IRQ mapping properties
> > +  Please refer to the standard PCI bus binding document for a more detailed
> > +  explanation.
> 
> Child nodes do not normally have interrupt-map properties. Isn't this
> already covered by the interrupt-map in the parent?
> 

I have one Intel 4 port ethernet card(0000:00:01) and MTK WLAN card
(0000:00:02), probe message looks good to me.

pci 0000:00:01.0: fixup irq: got 224
pci 0000:00:01.0: assigning IRQ 224
pci 0000:00:02.0: fixup irq: got 225
pci 0000:00:02.0: assigning IRQ 225

pci 0000:01:00.0: fixup irq: got 224
pci 0000:01:00.0: assigning IRQ 224
pci 0000:01:00.1: fixup irq: got 224
pci 0000:01:00.1: assigning IRQ 224
pci 0000:01:00.2: fixup irq: got 224
pci 0000:01:00.2: assigning IRQ 224
pci 0000:01:00.3: fixup irq: got 224
pci 0000:01:00.3: assigning IRQ 224

pci 0000:02:00.0: fixup irq: got 225
pci 0000:02:00.0: assigning IRQ 225


But child nodes without interrupt-map properties:
It seems incorrect.

pci 0000:00:01.0: fixup irq: got 224
pci 0000:00:01.0: assigning IRQ 224
pci 0000:00:02.0: fixup irq: got 225
pci 0000:00:02.0: assigning IRQ 225

pci 0000:01:00.0: fixup irq: got 223
pci 0000:01:00.0: assigning IRQ 223
pci 0000:01:00.1: fixup irq: got 223
pci 0000:01:00.1: assigning IRQ 223
pci 0000:01:00.2: fixup irq: got 223
pci 0000:01:00.2: assigning IRQ 223
pci 0000:01:00.3: fixup irq: got 223
pci 0000:01:00.3: assigning IRQ 223

pci 0000:02:00.0: fixup irq: got 223
pci 0000:02:00.0: assigning IRQ 223