Commit-ID: 45b586ef231abf29bff2b91efb74c10d01a0d79c
Gitweb: http://git.kernel.org/tip/45b586ef231abf29bff2b91efb74c10d01a0d79c
Author: Nicolai Stange <nicstange@xxxxxxxxx>
AuthorDate: Thu, 30 Mar 2017 21:57:43 +0200
Committer: John Stultz <john.stultz@xxxxxxxxxx>
CommitDate: Fri, 14 Apr 2017 13:11:21 -0700
tile/time: Set ->min_delta_ticks and ->max_delta_ticks
In preparation for making the clockevents core NTP correction aware,
all clockevent device drivers must set ->min_delta_ticks and
->max_delta_ticks rather than ->min_delta_ns and ->max_delta_ns: a
clockevent device's rate is going to change dynamically and thus, the
ratio of ns to ticks ceases to stay invariant.
Currently, the tile's timer clockevent device is initialized as follows:
evt->max_delta_ns = clockevent_delta2ns(MAX_TICK, evt);
and
.min_delta_ns = 1000,
The first one translates to a ->max_delta_ticks value of MAX_TICK.
For the latter, note that the clockevent core will superimpose a
minimum of 1us by itself -- setting ->min_delta_ticks to 1 is safe here.
Initialize ->min_delta_ticks and ->max_delta_ticks with these values.
This patch alone doesn't introduce any change in functionality as the
clockevents core still looks exclusively at the (untouched) ->min_delta_ns
and ->max_delta_ns. As soon as this has changed, a followup patch will
purge the initialization of ->min_delta_ns and ->max_delta_ns from this
driver.
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
Cc: Richard Cochran <richardcochran@xxxxxxxxx>
Cc: Prarit Bhargava <prarit@xxxxxxxxxx>
Cc: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
Cc: Chris Metcalf <cmetcalf@xxxxxxxxxxxx>
Signed-off-by: Nicolai Stange <nicstange@xxxxxxxxx>
Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
---
arch/tile/kernel/time.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/arch/tile/kernel/time.c b/arch/tile/kernel/time.c
index 5bd4e88..6643ffb 100644
--- a/arch/tile/kernel/time.c
+++ b/arch/tile/kernel/time.c
@@ -155,6 +155,8 @@ static DEFINE_PER_CPU(struct clock_event_device, tile_timer) = {
.name = "tile timer",
.features = CLOCK_EVT_FEAT_ONESHOT,
.min_delta_ns = 1000,
+ .min_delta_ticks = 1,
+ .max_delta_ticks = MAX_TICK,
.rating = 100,
.irq = -1,
.set_next_event = tile_timer_set_next_event,
--
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