Hi Arnd, On Mon, Mar 13, 2017 at 2:28 PM, Arnd Bergmann <arnd@xxxxxxxx> wrote: > On Mon, Mar 13, 2017 at 2:13 PM, Geert Uytterhoeven > <geert@xxxxxxxxxxxxxx> wrote: >> On Mon, Mar 13, 2017 at 2:06 PM, Arnd Bergmann <arnd@xxxxxxxx> wrote: >>> On Mon, Mar 13, 2017 at 1:46 PM, Geert Uytterhoeven >>> <geert@xxxxxxxxxxxxxx> wrote: >>>> On Mon, Mar 13, 2017 at 1:41 PM, Arnd Bergmann <arnd@xxxxxxxx> wrote: >>>>> On Thu, Mar 9, 2017 at 7:18 PM, Geert Uytterhoeven >>>>> I'd prefer to not have to do the early registration at all and have fewer >>>>> special cases. Can you list a specific example that requires this? >>>> >>>> The specific example is the Renesas R-Car SYSC driver, which manages PM >>>> Domains and thus needs to be initialized from an early_initcall. >>> >>> Ok, and what prevents us from using information in DT to detect which >>> variant we have? Is this a case of absolutely having to know the exact >>> hardware revision at the time of initialization, or is it just to simplify the >>> implementation of the SYSC driver? >> >> The former. >> Preproduction versions of R-Car H3 have an additional power area, which no >> longer exists on H3 ES2.0. > > Ok. I'm still not happy about adding the workaround, but this seems like > a reasonable requirement, assuming that the preproduction versions of R-Car H3 > are important enough to you that supporting them in mainline helps you > get your work done better. That's indeed our motivation. Currently we all have preproduction SoCs, with limited (remote) access to R-Car H3 ES2.0. The goal is to: 1. Support both the ES1.x and ES2.0 SoC revisions in a single binary for now, 2. Make it clear which code supports ES1.x, so it can easily be identified and removed later, when production SoCs are deemed ubiquitous. > Please add the explanation to the changelog, along with my > > Acked-by: Arnd Bergmann <arnd@xxxxxxxx> Will do, thanks! Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds