On 01/04/18 13:47, Kyle Evans wrote: > On Thu, Jan 4, 2018 at 3:34 PM, Kyle Evans <kevans@xxxxxxxxxxx> wrote: >> On Thu, Jan 4, 2018 at 2:41 PM, Kyle Evans <kevans@xxxxxxxxxxx> wrote: >>> On Thu, Jan 4, 2018 at 2:33 PM, Frank Rowand <frowand.list@xxxxxxxxx> wrote: >>>> [... snip ...] >>>> >>>> Does this remove the need for the proposed patch, or am I still >>>> missing something? >>> >>> ... nope. Apparently I never tested this with this particular dtc(1) >>> and instead just assumed it did the same as ours- allocate phandle >>> sparsely, even with -@. That certainly removes the need for this >>> patch, and I'm somewhat upset that I hadn't previously considered >>> this. >>> >>> @David, Jon: Please disregard all of the patches along these lines... >>> I'll fix this in our dtc, where it should be fixed. >>> >>> Thanks, Frank! >> >> Actually, I'm kind of torn on whether this is useful or not. With >> being able to have EFI-provided FDT, it's hard to guarantee whether >> the FDT we're provided has been compiled with GPL dtc(1) and -@. The >> above solves this problem for most of my personal use-cases , though, >> since I can guarantee that our FDT and U-Boot provided FDT is compiled >> properly. > > Apologies for the triple post; I realized that this argument is > inherently wrong, since we can't reference the node if there's no > symbol anyways. > > The only way this might still be a good idea is to support more > minimal cases where an implementation might prefer to not create a > phandle for nodes that haven't been referenced. > > In our case, we have a function [1] that walks the tree and generates > metadata on nodes that have phandles, under the assumption that these > have been referenced somewhere and provides a way to more quickly > reference these specifically through a separate linked link. > Allocating phandles for everything as GPL dtc does adds quite a bit > more overhead to this. > > [1] http://src.illumos.org/source/xref/freebsd-head/sys/dev/ofw/openfirm.c#119 The "-@" option does not add a phandle to _every_ node, just to nodes that have a label: $ cat overlay_base_manual_symbols_auto_phandle--no__symbols__add_a_node.dts /* * Copyright (c) 2016 NextThing Co * Copyright (c) 2016 Free Electrons * * SPDX-License-Identifier: GPL-2.0+ */ /dts-v1/; / { test: test-node { test-int-property = <42>; test-str-property = "foo"; subtest: sub-test-node { sub-test-property; }; sub-test-node-2 { sub-test-property; }; sub-test-node-3 { sub-test-property; }; }; }; $ dtc -@ -O dts overlay_base_manual_symbols_auto_phandle--no__symbols__add_a_node.dts /dts-v1/; / { test: test-node { test-int-property = <0x2a>; test-str-property = "foo"; phandle = <0x1>; subtest: sub-test-node { sub-test-property; phandle = <0x2>; }; sub-test-node-2 { sub-test-property; }; sub-test-node-3 { sub-test-property; }; }; __symbols__ { test = "/test-node"; subtest = "/test-node/sub-test-node"; }; }; -- To unsubscribe from this list: send the line "unsubscribe devicetree-compiler" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
