From mboxrd@z Thu Jan 1 00:00:00 1970 From: jon-hunter@ti.com (Jon Hunter) Date: Wed, 7 Nov 2012 13:01:17 -0600 Subject: [PATCH V2 01/14] ARM: OMAP: Add DMTIMER definitions for posted mode In-Reply-To: <1352314890-22224-1-git-send-email-jon-hunter@ti.com> References: <1352314890-22224-1-git-send-email-jon-hunter@ti.com> Message-ID: <1352314890-22224-2-git-send-email-jon-hunter@ti.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org For OMAP2+ devices, when using DMTIMERs for system timers (clock-events and clock-source) the posted mode configuration of the timers is used. To allow the compiler to optimise the functions for configuring and reading the system timers, the posted flag variable is hard-coded with the value 1. To make it clear that posted mode is being used add some definitions so that it is more readable. Add separate definitions for the clock-events and clock-source timers so that we can change the posted mode of clock-events and clock-source independently. Signed-off-by: Jon Hunter --- arch/arm/mach-omap2/timer.c | 26 +++++++++++++++++++------- arch/arm/plat-omap/include/plat/dmtimer.h | 4 ++++ 2 files changed, 23 insertions(+), 7 deletions(-) diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c index 0758bae..28c6078 100644 --- a/arch/arm/mach-omap2/timer.c +++ b/arch/arm/mach-omap2/timer.c @@ -82,6 +82,13 @@ #define INCREMENTER_DENUMERATOR_RELOAD_OFFSET 0x14 #define NUMERATOR_DENUMERATOR_MASK 0xfffff000 +/* + * For clock-events timer, always use posted mode to + * minimise CPU overhead for configuring the timer. + */ +#define OMAP_CLKEVT_POSTEDMODE OMAP_TIMER_POSTED +#define OMAP_CLKSRC_POSTEDMODE OMAP_TIMER_POSTED + /* Clockevent code */ static struct omap_dm_timer clkev; @@ -107,7 +114,7 @@ static int omap2_gp_timer_set_next_event(unsigned long cycles, struct clock_event_device *evt) { __omap_dm_timer_load_start(&clkev, OMAP_TIMER_CTRL_ST, - 0xffffffff - cycles, 1); + 0xffffffff - cycles, OMAP_CLKEVT_POSTEDMODE); return 0; } @@ -117,7 +124,7 @@ static void omap2_gp_timer_set_mode(enum clock_event_mode mode, { u32 period; - __omap_dm_timer_stop(&clkev, 1, clkev.rate); + __omap_dm_timer_stop(&clkev, OMAP_CLKEVT_POSTEDMODE, clkev.rate); switch (mode) { case CLOCK_EVT_MODE_PERIODIC: @@ -125,10 +132,12 @@ static void omap2_gp_timer_set_mode(enum clock_event_mode mode, period -= 1; /* Looks like we need to first set the load value separately */ __omap_dm_timer_write(&clkev, OMAP_TIMER_LOAD_REG, - 0xffffffff - period, 1); + 0xffffffff - period, + OMAP_CLKEVT_POSTEDMODE); __omap_dm_timer_load_start(&clkev, OMAP_TIMER_CTRL_AR | OMAP_TIMER_CTRL_ST, - 0xffffffff - period, 1); + 0xffffffff - period, + OMAP_CLKEVT_POSTEDMODE); break; case CLOCK_EVT_MODE_ONESHOT: break; @@ -358,7 +367,8 @@ static bool use_gptimer_clksrc; */ static cycle_t clocksource_read_cycles(struct clocksource *cs) { - return (cycle_t)__omap_dm_timer_read_counter(&clksrc, 1); + return (cycle_t)__omap_dm_timer_read_counter(&clksrc, + OMAP_CLKSRC_POSTEDMODE); } static struct clocksource clocksource_gpt = { @@ -372,7 +382,8 @@ static struct clocksource clocksource_gpt = { static u32 notrace dmtimer_read_sched_clock(void) { if (clksrc.reserved) - return __omap_dm_timer_read_counter(&clksrc, 1); + return __omap_dm_timer_read_counter(&clksrc, + OMAP_CLKSRC_POSTEDMODE); return 0; } @@ -454,7 +465,8 @@ static void __init omap2_gptimer_clocksource_init(int gptimer_id, BUG_ON(res); __omap_dm_timer_load_start(&clksrc, - OMAP_TIMER_CTRL_ST | OMAP_TIMER_CTRL_AR, 0, 1); + OMAP_TIMER_CTRL_ST | OMAP_TIMER_CTRL_AR, 0, + OMAP_CLKSRC_POSTEDMODE); setup_sched_clock(dmtimer_read_sched_clock, 32, clksrc.rate); if (clocksource_register_hz(&clocksource_gpt, clksrc.rate)) diff --git a/arch/arm/plat-omap/include/plat/dmtimer.h b/arch/arm/plat-omap/include/plat/dmtimer.h index 348f855..835c3bdf 100644 --- a/arch/arm/plat-omap/include/plat/dmtimer.h +++ b/arch/arm/plat-omap/include/plat/dmtimer.h @@ -55,6 +55,10 @@ #define OMAP_TIMER_TRIGGER_OVERFLOW 0x01 #define OMAP_TIMER_TRIGGER_OVERFLOW_AND_COMPARE 0x02 +/* posted mode types */ +#define OMAP_TIMER_NONPOSTED 0x00 +#define OMAP_TIMER_POSTED 0x01 + /* timer capabilities used in hwmod database */ #define OMAP_TIMER_SECURE 0x80000000 #define OMAP_TIMER_ALWON 0x40000000 -- 1.7.9.5