Messages in this thread | | | From | Brad Larson <> | Date | Sun, 28 Mar 2021 18:07:50 -0700 | Subject | Re: [PATCH 7/8] arm64: dts: Add Pensando Elba SoC support |
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On Thu, Mar 4, 2021 at 12:03 AM Serge Semin <fancer.lancer@gmail.com> wrote: > > On Wed, Mar 03, 2021 at 07:41:40PM -0800, Brad Larson wrote: > > Add Pensando common and Elba SoC specific device nodes > > and corresponding binding documentation. > > This also needs to be split up into sub-patches seeing these are > unrelated changes like device bindings update, new platform DT file.
In patchset v2 this is split into sub-patches.
> What about converting this file to DT-schema and adding new HW > bindings in there?
Converted existing file devicetree/bindings/spi/cadence-quadspi.txt to YAML schema.
> > +&spi0 { > > + num-cs = <4>; > > > + cs-gpios = <&spics 0 0>, <&spics 1 0>, <&porta 1 0>, <&porta 7 0>; > > Oh, you've got four peripheral SPI devices connected with only two native CS > available. Hmm, then I don't really know a better way, but just to forget about > the native DW APB CS functionality and activate the direct driving of > all the CS-pins at the moment of the DW APB SPI controller probe > procedure. Then indeed you'll need a custom CS function defined in the DW APB > SPI driver to handle that.
Yes, with an Elba SoC specific gpio driver.
> So that GPIO-controller is just a single register which provides a way > to toggle the DW APB SPI CS-mode together with their output value. > If so and seeing there are a few more tiny spaces of config > registers added to eMMC, PCI, etc DT node, I suppose all of them > belong to some bigger config space of the SoC. Thus I'd suggest to at > least implement them as part of a System Controller DT node. Then use > that device service to switch on/off corresponding functionality. > See [2] and the rest of added to the kernel DTS files with > syscon-nodes for example. > > [2] Documentation/devicetree/bindings/mfd/syscon.yaml
To us it was more understandable to implement a standard gpio driver for the spi chip-selects.
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