| Date | Mon, 5 Nov 2012 15:22:19 -0800 | From | Tony Lindgren <> | Subject | Re: [RFC] Device Tree Overlays Proposal (Was Re: capebus moving omap_devices to mach-omap2) |
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Hi,
* Tabi Timur-B04825 <B04825@freescale.com> [121105 13:42]: > On Mon, Nov 5, 2012 at 2:40 PM, Grant Likely <grant.likely@secretlab.ca> wrote: > > > Jane is building custom BeagleBone expansion boards called 'capes'. She > > can boot the system with a stock BeagleBoard device tree, but additional > > data is needed before a cape can be used. She could replace the FDT file > > used by U-Boot with one that contains the extra data, but she uses the > > same Linux system image regardless of the cape, and it is inconvenient > > to have to select a different device tree at boot time depending on the > > cape. > > What's wrong with having the boot loader detect the presence of the > Cape and update the device tree accordingly? We do this all the time > in U-Boot. Doing stuff like reading EEPROMs and testing for the > presence of hardware is easier in U-Boot than in Linux. > > For configurations that can be determined by the boot loader, I'm not > sure overlays are practical.
I guess the beaglebone capes could be stackable and hotpluggable if handled carefully enough.
Regards,
Tony
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