Re: [PATCH 3/4] ARM: tegra: nyan-big: Include compatible revisions for proper detection
From: Jon Hunter <jonathanh@nvidia.com>
Date: 2016-09-21 09:15:32
Also in:
linux-arm-kernel, linux-tegra, lkml
On 21/09/16 08:43, Paul Kocialkowski wrote: ...
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Depthcharge (the payload used with cros devices) will attempt to detect boards using their revision. This includes all the known revisions for the nyan-big board so that the dtb can be selected preferably.May be I am missing something here, but for the mainline there is only one dtb available and so why is this needed for the mainline?There is indeed a single dts in mainline, but depthcharge will use the revision to match the compatible string (e.g. it will look for google,nyan-big- rev5, not google,nyan-big), so we need to list them all in that single dts. Otherwise, depthcharge will fall back to the default config, which may or may not be suitable for nyan.Is tegra124-nyan-big.dtb not the default?You can't expect that to always be the case. The image format allows many different dts to be provided, so I could easily build with multi_v7_defconfig and have various dts for various devices in the same image, and just select a random one as default.Really? Sounds odd. I was hoping that tegra124-nyan-big.dtb would be a catch all.
I meant I was hoping that compatible = "google,nyan-big" would be the catchall not the dtb file name ;-)
Yes, the image format (FIT) allows specifying multiple dtb and zImage combinations in the same image[0].
Yes I am aware of that. Typically, I have been testing using a FIT image with single zImage and dtb. Hence no problems. So are you wanting to create a FIT image to support multiple boards and use the single FIT image for all? If so then I can see why you want this. Again please describe the motivation for the changes in the changelog so it is clear why we are adding this. Cheers Jon -- nvpublic