On 5/15/2015 5:47 PM, Frank Rowand wrote: > On 5/12/2015 7:33 AM, Pantelis Antoniou wrote: >> Hi Geert, >> >>> On May 12, 2015, at 14:56 , Geert Uytterhoeven <geert+renesas@xxxxxxxxx> wrote: >>> >>> This allows to handle device tree overlays like plain device trees. >>> >>> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx> >>> --- >>> Questions: >>> - Do we want dtso files under arch/<arch>/boot/dts/, too? >>> - Do we want to move the dts files outside the kernel repository >>> first? >>> >> >> Oh that’s a nice hornet’s nest you’ve kicked here. >> >> arch/<arch>/boot/dts should not be the place, cause overlays are not related with boot per se. >> As they are right now are board (family) specific. > > Aren't overlays meant to describe child boards (capes, shields, whatever) that may > vary from system to system, but are not expected to be hot-plugged while the OS > is up? Or is hot-plug a design goal? To reply to myself, there is a current discussion about whether to use overlays to help with a powerpc pci desire to add and delete subtrees: http://www.spinics.net/lists/linux-pci/msg40740.html That sound like hot-plug to me... > > If no hot-plug, then to me an overlay is just as related to boot as the base dts. > It is a mere implementation detail that overlays are "loaded" from userspace > instead of by the booting kernel (I don't really know the details of using > overlays, so please correct me if I am wrong about how the kernel becomes aware > of an overlay). > >> >> I think we should try to keep an external kernel repo with them for now until we >> figure out where to put them. >> >>> scripts/Makefile.lib | 3 +++ >>> 1 file changed, 3 insertions(+) >>> >>> diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib >>> index 79e86613712f2230..4b14eef1d4b2ce8f 100644 >>> --- a/scripts/Makefile.lib >>> +++ b/scripts/Makefile.lib >>> @@ -292,6 +292,9 @@ cmd_dtc = mkdir -p $(dir ${dtc-tmp}) ; \ >>> $(obj)/%.dtb: $(src)/%.dts FORCE >>> $(call if_changed_dep,dtc) >>> >>> +$(obj)/%.dtbo: $(src)/%.dtso FORCE >>> + $(call if_changed_dep,dtc) >>> + >>> dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp) >>> >>> # Bzip2 >>> -- >>> 1.9.1 >> >> Regards >> >> — Pantelis >> >> -- >> To unsubscribe from this list: send the line "unsubscribe devicetree" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
