diff options
author | Xunlei Pang <pang.xunlei@linaro.org> | 2015-04-01 23:34:24 -0400 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2015-04-03 02:18:21 -0400 |
commit | a451570c008b9e19592e29f15cfd295bdf818c7a (patch) | |
tree | 86e5932d0b6c97641b4793d0211a71edb4ddc4b6 /arch/arm/plat-omap | |
parent | 3c00a1fe8496ff29ab62764bb3f4ce4b48089004 (diff) |
ARM: OMAP: 32k counter: Provide y2038-safe omap_read_persistent_clock() replacement
As part of addressing "y2038 problem" for in-kernel uses, this
patch adds the y2038-safe omap_read_persistent_clock64() using
timespec64.
Because we rely on some subsequent changes to convert arm
multiarch support, omap_read_persistent_clock() will be removed
then.
Also remove the needless spinlock, because
read_persistent_clock() doesn't run simultaneously.
Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Acked-by: Tony Lindgren <tony@atomide.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1427945681-29972-5-git-send-email-john.stultz@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/arm/plat-omap')
-rw-r--r-- | arch/arm/plat-omap/counter_32k.c | 22 |
1 files changed, 12 insertions, 10 deletions
diff --git a/arch/arm/plat-omap/counter_32k.c b/arch/arm/plat-omap/counter_32k.c index 43cf74561cfd..b7b7b0793228 100644 --- a/arch/arm/plat-omap/counter_32k.c +++ b/arch/arm/plat-omap/counter_32k.c | |||
@@ -44,24 +44,20 @@ static u64 notrace omap_32k_read_sched_clock(void) | |||
44 | } | 44 | } |
45 | 45 | ||
46 | /** | 46 | /** |
47 | * omap_read_persistent_clock - Return time from a persistent clock. | 47 | * omap_read_persistent_clock64 - Return time from a persistent clock. |
48 | * | 48 | * |
49 | * Reads the time from a source which isn't disabled during PM, the | 49 | * Reads the time from a source which isn't disabled during PM, the |
50 | * 32k sync timer. Convert the cycles elapsed since last read into | 50 | * 32k sync timer. Convert the cycles elapsed since last read into |
51 | * nsecs and adds to a monotonically increasing timespec. | 51 | * nsecs and adds to a monotonically increasing timespec64. |
52 | */ | 52 | */ |
53 | static struct timespec persistent_ts; | 53 | static struct timespec64 persistent_ts; |
54 | static cycles_t cycles; | 54 | static cycles_t cycles; |
55 | static unsigned int persistent_mult, persistent_shift; | 55 | static unsigned int persistent_mult, persistent_shift; |
56 | static DEFINE_SPINLOCK(read_persistent_clock_lock); | ||
57 | 56 | ||
58 | static void omap_read_persistent_clock(struct timespec *ts) | 57 | static void omap_read_persistent_clock64(struct timespec64 *ts) |
59 | { | 58 | { |
60 | unsigned long long nsecs; | 59 | unsigned long long nsecs; |
61 | cycles_t last_cycles; | 60 | cycles_t last_cycles; |
62 | unsigned long flags; | ||
63 | |||
64 | spin_lock_irqsave(&read_persistent_clock_lock, flags); | ||
65 | 61 | ||
66 | last_cycles = cycles; | 62 | last_cycles = cycles; |
67 | cycles = sync32k_cnt_reg ? readl_relaxed(sync32k_cnt_reg) : 0; | 63 | cycles = sync32k_cnt_reg ? readl_relaxed(sync32k_cnt_reg) : 0; |
@@ -69,11 +65,17 @@ static void omap_read_persistent_clock(struct timespec *ts) | |||
69 | nsecs = clocksource_cyc2ns(cycles - last_cycles, | 65 | nsecs = clocksource_cyc2ns(cycles - last_cycles, |
70 | persistent_mult, persistent_shift); | 66 | persistent_mult, persistent_shift); |
71 | 67 | ||
72 | timespec_add_ns(&persistent_ts, nsecs); | 68 | timespec64_add_ns(&persistent_ts, nsecs); |
73 | 69 | ||
74 | *ts = persistent_ts; | 70 | *ts = persistent_ts; |
71 | } | ||
72 | |||
73 | static void omap_read_persistent_clock(struct timespec *ts) | ||
74 | { | ||
75 | struct timespec64 ts64; | ||
75 | 76 | ||
76 | spin_unlock_irqrestore(&read_persistent_clock_lock, flags); | 77 | omap_read_persistent_clock64(&ts64); |
78 | *ts = timespec64_to_timespec(ts64); | ||
77 | } | 79 | } |
78 | 80 | ||
79 | /** | 81 | /** |