[PATCH v5 1/4] ARM: deprecate mach/timex.h for !ARCH_MULTIPLATFORM

Arnd Bergmann arnd at arndb.de
Tue Nov 5 06:34:42 EST 2013


On Tuesday 05 November 2013, Linus Walleij wrote:
> On Tue, Nov 5, 2013 at 10:12 AM, Uwe Kleine-König
> <u.kleine-koenig at pengutronix.de> wrote:
> 
> > +config NEED_MACH_TIMEX_H
> > +       bool
> > +       help
> > +         Select this when mach/timex.h is required to provide special
> > +         definitions for this platform. This should be avoided when possible.
> 
> OK this is no blocker, and do proceed with this as the kernel sure
> looks better after this than before it.
> 
> However as the next step I would prefer that we start to get rid of
> all the NEED_MACH_FOO_H used for just refactoring out headers.
> 
> Can we not completely do away with this header next, and provide
> the services it supplied locally in the mach-foo folder for these machines
> instead so we do not need to have all these Kconfig things and preserve
> the <mach/*> namespace for them?

Maybe we can collapse the CLOCK_TICK_RATE into a single Kconfig symbol
like


asm/timex.h:

#ifdef CONFIG_CLOCK_TICK_RATE
#define CLOCK_TICK_RATE CONFIG_CLOCK_TICK_RATE
#endif
/* EOF */

Kconfig:

config CLOCK_TICK_RATE
	int
	depends on !ARCH_MULTIPLATFORM && ARCH_USES_GETTIMEOFFSET
	depends on ARCH_GEMINI || ARCH_SA1100 || ARCH_EBSA110 || ARCH_EP93XX || ARCH_RPC || ARCH_AT91X40
	default 40000000 if ARCH_AT91X40
	default 38000000 if ARCH_GEMINI
	default 3686400 if ARCH_SA1100
	default 47894000 if ARCH_EBSA110
	default 983040 if ARCH_EP93xx
	default 2000000 if ARCH_RPC
	# don't even think about adding more to this list, better get rid of the
	# existing ones by converting them to proper clocksources

> The real trick is to make CLOCK_TICK_RATE and LATCH runtime
> variables instead of a compile-time variables, right? Can't we do
> this?

We've almost killed off CLOCK_TICK_RATE for anything that matters, I'd prefer not
doing anything to it other than reducing its uses to the places that we know need
it.

	Arnd



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