On Apr 17, 2018, at 16:17, Luke Kenneth Casson Leighton lkcl@lkcl.net wrote:
On Tue, Apr 17, 2018 at 11:12 PM, Richard Wilbur richard.wilbur@gmail.com wrote:
In my estimation the tasks that can be completed relatively quickly are 1 and 3 as they don't require convincing anyone else of the importance of the goal or merit of the implementation.
it is slightly more complex (3 that is) because a library and associated linux kernel device-driver has to also be written that reads from the I2C EEPROM (to be added to both u-boot and the linux kernel), in order to use the devicetree fragment merging... overlay! that's what it's called.
it is *not* going to be okay to just blop in one devicetree file for eoma68-a20-with-microdesktop, one devicetree file for eoma68-rk3288-with-microdesktop, one devicetree file for eoma68-a20-with-laptop-housing, one devicetree file for eoma68-rk3288-with-laptop-housing etc. etc.
preventing that kind of insane O(N * M) devicetree proliferation and reducing it down to O(N + M) *IS* the entire point of the EOMA68
I agree wholeheartedly with the modular mix and match overlay fragment design but saw the software support for it in what I had labelled as priority 4. Whereas I understood priority 3 to entail creating the devicetree fragments for the EOMA hardware that already exists.
1. Hack together some tests under 3.4.104 that we can run on the extant
drivers.
2. Work on getting extant A20 drivers mainlined in the linux kernel.
3. Create devicetree [fragments] for DS113 v2.7.4 and v2.7.5, … (all extant versions
of DS113 and microdesktop case).
4. Work on getting devicetree with [fragment] add/remove overlay support mainlined in
the linux kernel (and u-boot?).
Let me restate without relying only on numbers to identify the tasks: We can create the tests to run on 3.4.104 kernel (priority 1) and the devicetree overlays or fragments for each version of the processor card and microdesktop case (priority 3) without buy in from anyone else.
Getting the A20 drivers mainlined in the linux kernel (priority 2) and devicetree fragment overlay add/remove support in the linux kernel and u-boot (priority 4) will require continued collaboration with those who maintain the linux kernel and u-boot. Others have already been working on this effort for several years.