Re: [PATCH] sh: exports for delay.h

Hi Al,

On Fri, Dec 27, 2024 at 5:22 PM Al Viro <[email protected]> wrote:
> On Fri, Dec 27, 2024 at 04:58:58PM +0100, Geert Uytterhoeven wrote:
> > Please do not export __delay, as it is an internal implementation detail.
> > Drivers should not call __delay() directly, as it has non-standardized
> > semantics, or may not even exist.
>
> As the matter of fact, it *does* exist and is either exported or a static
> inline with everything used by it exported - on every architecture except sh.

OK, it does exist, because init/calibrate.c needs it. But that should
be the sole user outside architecture-specific code.

Unlike some other architectures, SH does not emit calls to __delay()
from various (static inline) *delay() functions.  Hence there is no
need to export it to modules. Heck, the only reason it cannot be made
static is because init/calibrate.c needs it.

Unfortunately there are still a few drivers that call __delay()
directly (usually with hardcoded constants, how portable, and
cpufreq-unfriendly), which causes people to try once in a while to
"fix the build" by re-adding the export on SH :-(

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]

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