2016-09-24 5:27 GMT+02:00 Luke Kenneth Casson Leighton lkcl@lkcl.net:
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Let's switch to the Pocket QWERTY Computer as an example instead of
router. The A20 cpu card ships with Parabola, a desktop/workstation style OS. I want my customers to have a good experience when they use my handheld housing. Using an OS tailored for desktop/workstation computing is *not* a good experience on a small screen (I've tried this with the Zipit and it "worked", but was not very productive). I can make this transition even *easier* for average consumer by supplying a SD card with Replicant or some other custom libre distribution designed for small screens.
or, you could supply multiple OS SD cards for them, and set up the NAND to look an OS on the A20's MicroSD Card slot.
yes, i'm keenly aware that the alteration of the OS to suit LCD size is a Big Deal. putting it another way: it's a PAIN IN THE ASS! :)
it's made even more complicated (for the A20) by the fact that the people who did the sunxi u-boot and mainline kernel didn't think about this in advance: they've specified that the LCD shall be set up by u-boot and u-boot alone, leaving absolutely no possibility for changing the LCD size without a total reboot! oops...
Not quite sure that is the case. U-Boot provides "early" setup, regulator and clocks etc., for u-boot output. SimpleFB takes over the settings from U-Boot (via u-boot modified device-tree). But a proper KMS/DRM driver (sunxi has something working for A13, H3, A33) may change all that. Too bad that libv got burned and refused to release his work. https://lkml.org/lkml/2015/10/30/358 http://linux-sunxi.org/Linux_mainlining_effort
So yeah for SimpleFB you're bound to change the display settings in advance of a (re)boot. To the specific device. With proper KMS not.
Which leads to the EOMA68 minimum allowed display resolution should be set in U-Boot.
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