[PATCH] omap1: Fix sched_clock implementation when both MPU timer and 32K timer are used (Re: State of LDP3430 platform)
From: tony@atomide.com (Tony Lindgren)
Date: 2011-01-19 18:43:21
Also in:
linux-omap
* Tony Lindgren [off-list ref] [110118 15:20]:
* Tony Lindgren [off-list ref] [110118 14:34]:quoted
For omap15xx and 730 we need to use the MPU timer as the 32K timer is not available. For omap16xx we want to use the 32K timer because of PM. Fix this by allowing to build in both timers.This still needs one more patch to deal with the sched_clock for MPU timer..
And here's that patch to make sched_clock work with both timers. Tony From: Tony Lindgren <tony@atomide.com> Date: Tue, 18 Jan 2011 17:00:00 -0800 Subject: [PATCH] omap1: Fix sched_clock implementation when both MPU timer and 32K timer are used Earlier patches select HAVE_SCHED_CLOCK for omaps. To have working sched_clock also for MPU timer, we need to implement it in a way where the right one gets selected during the runtime. Signed-off-by: Tony Lindgren <tony@atomide.com>
--- a/arch/arm/mach-omap1/time.c
+++ b/arch/arm/mach-omap1/time.c@@ -219,6 +219,24 @@ static struct clocksource clocksource_mpu = { static DEFINE_CLOCK_DATA(cd); +static inline unsigned long long notrace _omap_mpu_sched_clock(void) +{ + u32 cyc = mpu_read(&clocksource_mpu); + return cyc_to_sched_clock(&cd, cyc, (u32)~0); +} + +#ifndef CONFIG_OMAP_32K_TIMER +unsigned long long notrace sched_clock(void) +{ + return _omap_mpu_sched_clock(); +} +#else +static unsigned long long notrace omap_mpu_sched_clock(void) +{ + return _omap_mpu_sched_clock(); +} +#endif + static void notrace mpu_update_sched_clock(void) { u32 cyc = mpu_read(&clocksource_mpu);
@@ -262,6 +280,30 @@ static inline void omap_mpu_timer_init(void) } #endif /* CONFIG_OMAP_MPU_TIMER */ +#if defined(CONFIG_OMAP_MPU_TIMER) && defined(CONFIG_OMAP_32K_TIMER) +static unsigned long long (*preferred_sched_clock)(void); + +unsigned long long notrace sched_clock(void) +{ + if (!preferred_sched_clock) + return 0; + + return preferred_sched_clock(); +} + +static inline void preferred_sched_clock_init(bool use_32k_sched_clock) +{ + if (use_32k_sched_clock) + preferred_sched_clock = omap_32k_sched_clock; + else + preferred_sched_clock = omap_mpu_sched_clock; +} +#else +static inline void preferred_sched_clock_init(bool use_32k_sched_clcok) +{ +} +#endif + static inline int omap_32k_timer_usable(void) { int res = false;
@@ -283,8 +325,12 @@ static inline int omap_32k_timer_usable(void) */ static void __init omap_timer_init(void) { - if (!omap_32k_timer_usable()) + if (omap_32k_timer_usable()) { + preferred_sched_clock_init(1); + } else { omap_mpu_timer_init(); + preferred_sched_clock_init(0); + } } struct sys_timer omap_timer = { --- a/arch/arm/plat-omap/counter_32k.c +++ b/arch/arm/plat-omap/counter_32k.c
@@ -120,12 +120,24 @@ static DEFINE_CLOCK_DATA(cd); #define SC_MULT 4000000000u #define SC_SHIFT 17 -unsigned long long notrace sched_clock(void) +static inline unsigned long long notrace _omap_32k_sched_clock(void) { u32 cyc = clocksource_32k.read(&clocksource_32k); return cyc_to_fixed_sched_clock(&cd, cyc, (u32)~0, SC_MULT, SC_SHIFT); } +#ifndef CONFIG_OMAP_MPU_TIMER +unsigned long long notrace sched_clock(void) +{ + return _omap_32k_sched_clock(); +} +#else +unsigned long long notrace omap_32k_sched_clock(void) +{ + return _omap_32k_sched_clock(); +} +#endif + static void notrace omap_update_sched_clock(void) { u32 cyc = clocksource_32k.read(&clocksource_32k); --- a/arch/arm/plat-omap/include/plat/common.h +++ b/arch/arm/plat-omap/include/plat/common.h
@@ -37,6 +37,7 @@ extern void omap_map_common_io(void); extern struct sys_timer omap_timer; extern bool omap_32k_timer_init(void); extern int __init omap_init_clocksource_32k(void); +extern unsigned long long notrace omap_32k_sched_clock(void); extern void omap_reserve(void);