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Commit a1c57e0f authored by John Stultz's avatar John Stultz Committed by John Stultz
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blackfin: convert to clocksource_register_hz 



This converts the blackfin clocksource to use clocksource_register_hz.

CC: Mike Frysinger <vapier@gentoo.org>
CC: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarJohn Stultz <johnstul@us.ibm.com>
parent 75c4fd8c

arch/blackfin/kernel/time-ts.c

+2 −33
Original line number Diff line number Diff line
@@ -23,29 +23,6 @@ 
#include <asm/gptimers.h>

#include <asm/nmi.h>



/* Accelerators for sched_clock()

 * convert from cycles(64bits) => nanoseconds (64bits)

 *  basic equation:

 *		ns = cycles / (freq / ns_per_sec)

 *		ns = cycles * (ns_per_sec / freq)

 *		ns = cycles * (10^9 / (cpu_khz * 10^3))

 *		ns = cycles * (10^6 / cpu_khz)

 *

 *	Then we use scaling math (suggested by george@mvista.com) to get:

 *		ns = cycles * (10^6 * SC / cpu_khz) / SC

 *		ns = cycles * cyc2ns_scale / SC

 *

 *	And since SC is a constant power of two, we can convert the div

 *  into a shift.

 *

 *  We can use khz divisor instead of mhz to keep a better precision, since

 *  cyc2ns_scale is limited to 10^6 * 2^10, which fits in 32 bits.

 *  (mathieu.desnoyers@polymtl.ca)

 *

 *			-johnstul@us.ibm.com "math is hard, lets go shopping!"

 */



#define CYC2NS_SCALE_FACTOR 10 /* 2^10, carefully chosen */



#if defined(CONFIG_CYCLES_CLOCKSOURCE)
@@ -63,7 +40,6 @@ static struct clocksource bfin_cs_cycles = { 
	.rating		= 400,

	.read		= bfin_read_cycles,

	.mask		= CLOCKSOURCE_MASK(64),

	.shift		= CYC2NS_SCALE_FACTOR,

	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,

};
@@ -75,10 +51,7 @@ static inline unsigned long long bfin_cs_cycles_sched_clock(void) 


static int __init bfin_cs_cycles_init(void)

{

	bfin_cs_cycles.mult = \

		clocksource_hz2mult(get_cclk(), bfin_cs_cycles.shift);



	if (clocksource_register(&bfin_cs_cycles))

	if (clocksource_register_hz(&bfin_cs_cycles, get_cclk()))

		panic("failed to register clocksource");



	return 0;
@@ -111,7 +84,6 @@ static struct clocksource bfin_cs_gptimer0 = { 
	.rating		= 350,

	.read		= bfin_read_gptimer0,

	.mask		= CLOCKSOURCE_MASK(32),

	.shift		= CYC2NS_SCALE_FACTOR,

	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,

};
@@ -125,10 +97,7 @@ static int __init bfin_cs_gptimer0_init(void) 
{

	setup_gptimer0();



	bfin_cs_gptimer0.mult = \

		clocksource_hz2mult(get_sclk(), bfin_cs_gptimer0.shift);



	if (clocksource_register(&bfin_cs_gptimer0))

	if (clocksource_register_hz(&bfin_cs_gptimer0, get_sclk()))

		panic("failed to register clocksource");



	return 0;