Re: [PATCH v2 0/6] Boot logo supplied by the device tree
Rob Herring <[email protected]> Wed, 5 Aug 2026 09:09:41 -0500
| Newsgroups | gmane.linux.drivers.devicetree,gmane.comp.video.dri.devel,gmane.linux.kernel |
|---|---|
| Message-ID | <[email protected]> |
On Wed, Aug 05, 2026 at 12:56:11AM +0200, Max Pedraza wrote: > This series lets the logo be described by the device tree instead: a node > compatible with "linux,boot-logo-clut224" under /chosen supplies the image in > the same paletted format the built-in CLUT224 logos already use, and the kernel > prefers it over the built-in ones when it is present and enabled. If the > node is absent or disabled, nothing changes. Why is this linux specific? Don't people want to do a splash screen in u-boot or other firmware? > > The image can come from the node itself (patches 1-2) or from a reserved > memory region the bootloader filled in (patches 4-5), because the image and > its placement are independent axes of variation. One board sold to several > customers wants several device trees differing in the logo. One customer > with several products built on that board, with different panels, wants the > same logo placed differently on each: there the image belongs in a shared > binary and only the placement belongs in the device tree. Patch 3 adds that > placement. > > We have been carrying a cruder version of this downstream on an AM335x > product since 2020, across a handful of board revisions, and it has removed > a real maintenance burden for us. This is an attempt to find out whether > something along these lines is wanted upstream, and if so in what shape -- > hence RFC. > > The v1 discussion turned on the obvious objection, that a bitmap is not > hardware and the device tree is not where it belongs. Geert pointed out that > configuration which is not hardware description goes under /chosen, and that > Open Firmware, which the device tree descends from, already carried a boot > logo in that spirit as the oem-logo variable under /options. The node has > moved to /chosen accordingly, which is also where simple-framebuffer nodes > live, for the same reason: they describe what firmware handed over rather > than what the hardware is. What does /options/oem-logo look like? Why can't that be used? > Patches 4 and 5 are separable; the series is useful without them if the > reserved memory path is thought to be one mechanism too many. If you are going to put it in memory, why not just draw it into the simple-framebuffer? Rob