Hello Robert, On Thu, 25 Jul 2013 11:21:10 -0700 Robert Winkler <robert.wink...@boundarydevices.com> wrote:
> Hello all, > > We're trying to figure out how best to get rid of static code like this: > > http://git.denx.de/?p=u-boot.git;a=blob;f=board/boundary/nitrogen6x/nitrogen6x.c;h=8f0f9b8de2e8e77fcbf477728ea063a213941dd0;hb=HEAD#l526 > > and turn it into run time data. > > Our idea is to use an environment variable so adding support for new > screens and iterating on minor settings is quick and easy and then we can > remove the static arrays like the one above and in wandboard.c and other > places. We have some code and users to define timing parameters in an environment variable "videomode". video_get_params() is used to read the parameters into a structure "struct ctfb_res_modes". > One way to do this is to create a data structure that can subsume the > functionalities of of display_info_t and the various structures in lcd.h > and elsewhere that can be used throughout U-Boot both with CONFIG_LCD and > CONFIG_CFB_CONSOLE. Combined with the EDID functionality already in U-Boot > this would allow code to easily select the "best" display supported by the > monitor or closest to what the user wanted (given in the environment > variable). This data structure would then be passed to Linux on boot up. > > I realize that there's already the FDT and CONFIG_OF_CONTROL functionality > and device trees sort of cover the passing to Linux part so maybe before > handing it off, converting the relevant data into a device tree that Linux > can already use/parse would work. Devicetree bindings for describing display timings info exist in recent Linux kernel versions (since v3.9 I think) and are documented under Documentation/devicetree/bindings/video/display-timing.txt. In Linux there are also DT helpers to parse display timings nodes and read the timing values into fb_videomode structure (of_get_display_timings, of_get_fb_videomode). Code for adding such display timings nodes to the device tree under U-Boot doesn't exist yet. > Is anyone working on something like this? Am I missing something that's > already in place to accomplish this? Maybe you can use "videomode" Variable and video_get_params(). Thanks, Anatolij _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
