Messages in this thread | | | Date | Mon, 30 Nov 2020 16:33:57 +0100 | From | Steen Hegelund <> | Subject | Re: [RFC PATCH 1/3] dt-bindings: net: sparx5: Add sparx5-switch bindings |
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On 30.11.2020 15:05, Andrew Lunn wrote: >EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe > >On Mon, Nov 30, 2020 at 02:09:34PM +0100, Steen Hegelund wrote: >> On 27.11.2020 18:00, Andrew Lunn wrote: >> > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe >> > >> > > + reg-names: >> > > + minItems: 153 >> > > + items: >> > > + - const: dev2g5_0 >> > > + - const: dev5g_0 >> > > + - const: pcs5g_br_0 >> > > + - const: dev2g5_1 >> > > + - const: dev5g_1 >> > ... >> > > + - const: ana_ac >> > > + - const: vop >> > >> > > + switch: switch@600000000 { >> > > + compatible = "microchip,sparx5-switch"; >> > > + reg = <0x10004000 0x4000>, /* dev2g5_0 */ >> > > + <0x10008000 0x4000>, /* dev5g_0 */ >> > > + <0x1000c000 0x4000>, /* pcs5g_br_0 */ >> > > + <0x10010000 0x4000>, /* dev2g5_1 */ >> > > + <0x10014000 0x4000>, /* dev5g_1 */ >> > >> > ... >> > >> > > + <0x11800000 0x100000>, /* ana_l2 */ >> > > + <0x11900000 0x100000>, /* ana_ac */ >> > > + <0x11a00000 0x100000>; /* vop */ >> > >> > This is a pretty unusual binding. >> > >> > Why is it not >> > >> > reg = <0x10004000 0x1af8000> >> > >> > and the driver can then break up the memory into its sub ranges? >> > >> > Andrew >> Hi Andrew, >> >> Since the targets used by the driver is not always in the natural >> address order (e.g. the dev2g5_x targets), I thought it best to let the DT >> take care of this since this cannot be probed. I am aware that this causes >> extra mappings compared to the one-range strategy, but this layout seems more >> transparent to me, also when mapped over PCIe. > >The question is, do you have a device tree usage for this? Are there >devices in the family which have the regions in a different order? >
Hi Andrew,
Yes we do have more chips in the pipeline that we expect to be able to use this driver. But I see your point. The new chips most certainly will have a different number of targets (that will most likely map to different addresses).
The bindings will need to be able to cope with the different number of targets, and I think that will be difficult.
So all in all I think I will rework this, and make the mapping in the driver instead.
>You can easily move this table into the driver, and let the driver >break the region up. That would be normal. > > Andrew
BR Steen
--------------------------------------- Steen Hegelund steen.hegelund@microchip.com
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