"M. Warner Losh" <[email protected]> writes: > <[email protected]> > <[email protected]> > X-Mailer: Mew version 5.2 on Emacs 21.3 / Mule 5.0 (SAKAKI) > Mime-Version: 1.0 > Content-Type: Text/Plain; charset=us-ascii > Content-Transfer-Encoding: 7bit > > In message: <[email protected]> > Carl-Daniel Hailfinger <[email protected]> writes: > : > I didn't mean to say they are a bad idea for FDTs, just that they're on > : > an awkward level of abstraction for QEMU configuration. There, I'd > : > rather express a PCI address as "02:01.0" than as <0x00000220>. > : > Translating text to binary is the machine's job, not the user's. > : > : Coreboot v3 is using some device tree variant which is IMHO a bit more > : user friendly. The tree below is incomplete (for example, it leaves out > : the PCI bus number and assumes that it is zero by default), but you > : surely get the idea. > : > : /{ > : mainboard_vendor = "Gigabyte"; > : mainboard_name = "M57SLI"; > : cpus { }; > : a...@0 { > : }; > : dom...@0 { > : p...@0,0 { /* MCP55 RAM? */ > : }; > : p...@1,0 { > : /config/("southbridge/nvidia/mcp55/lpc.dts"); > : iop...@2e { > > <etc> > > I'd like to make a couple of comments here. > > One, I dislike the DTS syntax. It is hard to learn to read, and I > always have to have the manual in my hands to read it. > > However, every board that's being produced for powerpc has the DTB at > least available. It has to be, or (recent?) Linux kernels flat out > won't work. This suggests that it might be a good idea to look at > this format. > > There's DTS and DTB. One is the source, the other is the binary > created from the source. I'd recommend that qemu actually use the DTB > rather than the DTS to implement things. This way one could have a > nicer syntax like the above and generate the DTB, or one could use the > DTS provided by a vendor if there was a more specific board they > wanted qemu to emulate.
As far as I know, dtc can decompile DTB into DTS. I'm not a fan of DTS syntax either, but if we choose FDT, then inventing an alternative syntax seems rather pointless to me. As to reading configuration in a binary format: let's not complicate things more than we need. It's just a decorated tree, folks. [...] _______________________________________________ devicetree-discuss mailing list [email protected] https://ozlabs.org/mailman/listinfo/devicetree-discuss
