[U-Boot] Making U-Boot smaller

[Marek Vasut]

On 5/21/19 6:43 PM, Simon Glass wrote:
> Hi,
> 
> (moved from thread "U-Boot PXA support")
> 
> We have of-platdata, which produces C data from the DT, for linking
> into U-Boot. It saves libfdt and DT space. But we still have the DM
> overhead.
> 
> We have binman which can insert values into the binary after
> link-time. This is barely used at present, only for accessing the
> location of things in flash.
> 
> Another thing is that every little tweak and feature adds a few bytes
> and there are dozens of them in each release. It would be interesting
> to build a board from 10 years ago (like PXA) and see where the growth
> is. My bet is that we could add Kconfig options to disable extra
> features (and enhancements of features) and make quite a difference.
> 
> For DM, I think it would be interesting to revisit and compare against
> the initial release, and see if some features could be made optional
> in SPL.
> 
> Finally I feel we could implement a single-device API for where
> CONFIG_SPL_DM is not set. We could use the debug UART for serial, a
> single instance of tiny MMC for MMC, etc.

If it's a single-instance, then maybe we can somehow compile-out or
short-circuit the DM altogether ?

-- 
Best regards,
Marek Vasut