[PATCH 0/9] (mostly) x86 kernel configuration adjustments

[Felix Fietkau]

On 29.04.23 02:50, Elliott Mitchell wrote:
> On Thu, Apr 27, 2023 at 05:38:18AM +0200, Stefan Lippers-Hollmann wrote:
>> On 2023-04-26, Elliott Mitchell wrote:
>> > On Thu, Apr 27, 2023 at 01:11:13AM +0200, Stefan Lippers-Hollmann wrote:
>> > > On 2023-04-26, Elliott Mitchell wrote:
>> > > [...]
>> > > > 
>> > > > Looks like little of ISA remained on "64", yet some DMA support remained
>> > > > due to the generic configuration.  Remove the ISA and ISA DMA support
>> > > > from the top-level configuration.  Geode and Legacy though almost
>> > > > certainly still need ISA support.
>> > > 
>> > > You might find that while ISA went away as an addon slot quite quickly,
>> > > it still survived rather long for low performance onboard devices (e.g. 
>> > > sensors).
>> > 
>> > I know, I was unsure of when it 100% disappeared.  Do you expect anything
>> > besides "legacy" to be used for this type of system though?
>> [...]
>> 
>> Ignoring industrial PCs (where you may still encounter ISA today), 
>> you'd have to venture into the pre-LPC days (and AMD, VIA, nVidia 
>> might have gone with ISA beyond that) - which might get you into
>> the 2005-2009 time frame (anything with an onboard floppy controller
>> might be worth looking at - and those were still around into the 
>> LGA755/ core2 (x86_64) days - in that particular case probably LPC 
>> based though).
> 
> Perhaps have "64" and "old64" (or "early64") then?  Seems rather a lot of
> legacy disappeared between 2005 and 2010.  FDC, ISA, PATA and AGP were
> all common in 2005, yet by 2010 they were non-existant.

If you need a build for yourself with a specialized stripped down kernel 
config, there is an easy (and reasonably maintainable) approach to doing so.

First you need to use this:
https://openwrt.org/docs/guide-developer/toolchain/env
Create an env for your main config.
Afterwards, you can run: make kernel_menuconfig CONFIG_TARGET=env
Any change you make there will be stored in env/kernel-config, which is 
an overlay that is applied on top of the target config.
You can use it to disable any features you like without having to modify 
any files in the OpenWrt source directory, and it should continue to 
work with pretty much any source tree updates.

- Felix