From 6a3fde9a5b80cdac76d79c65d20d7dd1f1d9e557 Mon Sep 17 00:00:00 2001 From: Gabe Black Date: Fri, 9 Aug 2013 00:56:40 -0700 Subject: [PATCH] exynos: Simplify the monotonic timer implementation. The previous implementation was overly complicated, and when used in the timestamp implementation produced some weird and broken results. BUG=chrome-os-partner:19420 TEST=Built and booted on pit. Used cbmem to check the timestamps and saw that they were now monotonically ascending and within reasonable bounds. BRANCH=None Change-Id: I3048028ddea0657b01b0c94f312764b38d1397e4 Signed-off-by: Gabe Black Reviewed-on: https://gerrit.chromium.org/gerrit/65302 Reviewed-by: Ronald G. Minnich Commit-Queue: Stefan Reinauer Reviewed-by: Stefan Reinauer Tested-by: Stefan Reinauer --- src/cpu/samsung/exynos5250/monotonic_timer.c | 28 +++----------------- src/cpu/samsung/exynos5420/monotonic_timer.c | 28 +++----------------- 2 files changed, 8 insertions(+), 48 deletions(-) diff --git a/src/cpu/samsung/exynos5250/monotonic_timer.c b/src/cpu/samsung/exynos5250/monotonic_timer.c index 57e3ae3104..267d9c3aef 100644 --- a/src/cpu/samsung/exynos5250/monotonic_timer.c +++ b/src/cpu/samsung/exynos5250/monotonic_timer.c @@ -18,40 +18,20 @@ */ #include -#include #include #include "clk.h" -static struct monotonic_counter { - int initialized; - struct mono_time time; - uint64_t last_value; -} mono_counter; +static int initialized; static const uint32_t clocks_per_usec = MCT_HZ/1000000; void timer_monotonic_get(struct mono_time *mt) { - uint64_t current_tick; - uint64_t usecs_elapsed; - - if (!mono_counter.initialized) { + if (!initialized) { mct_start(); - mono_counter.last_value = mct_raw_value(); - mono_counter.initialized = 1; + initialized = 1; } - current_tick = mct_raw_value(); - usecs_elapsed = (current_tick - mono_counter.last_value) / - clocks_per_usec; - - /* Update current time and tick values only if a full tick occurred. */ - if (usecs_elapsed) { - mono_time_add_usecs(&mono_counter.time, usecs_elapsed); - mono_counter.last_value = current_tick; - } - - /* Save result. */ - *mt = mono_counter.time; + mono_time_set_usecs(mt, mct_raw_value() / clocks_per_usec); } diff --git a/src/cpu/samsung/exynos5420/monotonic_timer.c b/src/cpu/samsung/exynos5420/monotonic_timer.c index 57e3ae3104..267d9c3aef 100644 --- a/src/cpu/samsung/exynos5420/monotonic_timer.c +++ b/src/cpu/samsung/exynos5420/monotonic_timer.c @@ -18,40 +18,20 @@ */ #include -#include #include #include "clk.h" -static struct monotonic_counter { - int initialized; - struct mono_time time; - uint64_t last_value; -} mono_counter; +static int initialized; static const uint32_t clocks_per_usec = MCT_HZ/1000000; void timer_monotonic_get(struct mono_time *mt) { - uint64_t current_tick; - uint64_t usecs_elapsed; - - if (!mono_counter.initialized) { + if (!initialized) { mct_start(); - mono_counter.last_value = mct_raw_value(); - mono_counter.initialized = 1; + initialized = 1; } - current_tick = mct_raw_value(); - usecs_elapsed = (current_tick - mono_counter.last_value) / - clocks_per_usec; - - /* Update current time and tick values only if a full tick occurred. */ - if (usecs_elapsed) { - mono_time_add_usecs(&mono_counter.time, usecs_elapsed); - mono_counter.last_value = current_tick; - } - - /* Save result. */ - *mt = mono_counter.time; + mono_time_set_usecs(mt, mct_raw_value() / clocks_per_usec); }