diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 23035d65252..0e1a9667a86 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -642,6 +642,7 @@ config ARCH_SA1100 select CPU_FREQ select GENERIC_CLOCKEVENTS select HAVE_CLK + select HAVE_SCHED_CLOCK select TICK_ONESHOT select ARCH_REQUIRE_GPIOLIB help diff --git a/arch/arm/mach-sa1100/generic.c b/arch/arm/mach-sa1100/generic.c index 33b4969e9d5..fbc224d88e6 100644 --- a/arch/arm/mach-sa1100/generic.c +++ b/arch/arm/mach-sa1100/generic.c @@ -16,9 +16,7 @@ #include #include #include -#include /* just for sched_clock() - funny that */ #include -#include #include #include @@ -109,27 +107,6 @@ unsigned int sa11x0_getspeed(unsigned int cpu) return cclk_frequency_100khz[PPCR & 0xf] * 100; } -/* - * This is the SA11x0 sched_clock implementation. This has - * a resolution of 271ns, and a maximum value of 32025597s (370 days). - * - * The return value is guaranteed to be monotonic in that range as - * long as there is always less than 582 seconds between successive - * calls to this function. - * - * ( * 1E9 / 3686400 => * 78125 / 288) - */ -unsigned long long notrace sched_clock(void) -{ - unsigned long long v = cnt32_to_63(OSCR); - - /* the <<1 gets rid of the cnt_32_to_63 top bit saving on a bic insn */ - v *= 78125<<1; - do_div(v, 288<<1); - - return v; -} - /* * Default power-off for SA1100 */ diff --git a/arch/arm/mach-sa1100/time.c b/arch/arm/mach-sa1100/time.c index 96154f578cd..ae4f3d80416 100644 --- a/arch/arm/mach-sa1100/time.c +++ b/arch/arm/mach-sa1100/time.c @@ -12,12 +12,39 @@ #include #include #include +#include /* just for sched_clock() - funny that */ #include #include #include +#include #include +/* + * This is the SA11x0 sched_clock implementation. + */ +static DEFINE_CLOCK_DATA(cd); + +/* + * Constants generated by clocks_calc_mult_shift(m, s, 3.6864MHz, + * NSEC_PER_SEC, 60). + * This gives a resolution of about 271ns and a wrap period of about 19min. + */ +#define SC_MULT 2275555556u +#define SC_SHIFT 23 + +unsigned long long notrace sched_clock(void) +{ + u32 cyc = OSCR; + return cyc_to_fixed_sched_clock(&cd, cyc, (u32)~0, SC_MULT, SC_SHIFT); +} + +static void notrace sa1100_update_sched_clock(void) +{ + u32 cyc = OSCR; + update_sched_clock(&cd, cyc, (u32)~0); +} + #define MIN_OSCR_DELTA 2 static irqreturn_t sa1100_ost0_interrupt(int irq, void *dev_id) @@ -96,6 +123,9 @@ static void __init sa1100_timer_init(void) OIER = 0; /* disable any timer interrupts */ OSSR = 0xf; /* clear status on all timers */ + init_fixed_sched_clock(&cd, sa1100_update_sched_clock, 32, + 3686400, SC_MULT, SC_SHIFT); + ckevt_sa1100_osmr0.mult = div_sc(3686400, NSEC_PER_SEC, ckevt_sa1100_osmr0.shift); ckevt_sa1100_osmr0.max_delta_ns =