releases/4.19.31/clocksource-drivers-exynos_mct-move-one-shot-check-from-tick-clear-to-isr.patch

   1 From a5719a40aef956ba704f2aa1c7b977224d60fa96 Mon Sep 17 00:00:00 2001
   2 From: Stuart Menefy <stuart.menefy@mathembedded.com>
   3 Date: Sun, 10 Feb 2019 22:51:13 +0000
   4 Subject: clocksource/drivers/exynos_mct: Move one-shot check from tick clear to ISR
   5
   6 From: Stuart Menefy <stuart.menefy@mathembedded.com>
   7
   8 commit a5719a40aef956ba704f2aa1c7b977224d60fa96 upstream.
   9
  10 When a timer tick occurs and the clock is in one-shot mode, the timer
  11 needs to be stopped to prevent it triggering subsequent interrupts.
  12 Currently this code is in exynos4_mct_tick_clear(), but as it is
  13 only needed when an ISR occurs move it into exynos4_mct_tick_isr(),
  14 leaving exynos4_mct_tick_clear() just doing what its name suggests it
  15 should.
  16
  17 Signed-off-by: Stuart Menefy <stuart.menefy@mathembedded.com>
  18 Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
  19 Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
  20 Cc: stable@vger.kernel.org # v4.3+
  21 Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
  22 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  23
  24 ---
  25  drivers/clocksource/exynos_mct.c |   22 +++++++++++-----------
  26  1 file changed, 11 insertions(+), 11 deletions(-)
  27
  28 --- a/drivers/clocksource/exynos_mct.c
  29 +++ b/drivers/clocksource/exynos_mct.c
  30 @@ -388,6 +388,13 @@ static void exynos4_mct_tick_start(unsig
  31         exynos4_mct_write(tmp, mevt->base + MCT_L_TCON_OFFSET);
  32  }
  33
  34 +static void exynos4_mct_tick_clear(struct mct_clock_event_device *mevt)
  35 +{
  36 +       /* Clear the MCT tick interrupt */
  37 +       if (readl_relaxed(reg_base + mevt->base + MCT_L_INT_CSTAT_OFFSET) & 1)
  38 +               exynos4_mct_write(0x1, mevt->base + MCT_L_INT_CSTAT_OFFSET);
  39 +}
  40 +
  41  static int exynos4_tick_set_next_event(unsigned long cycles,
  42                                        struct clock_event_device *evt)
  43  {
  44 @@ -420,8 +427,11 @@ static int set_state_periodic(struct clo
  45         return 0;
  46  }
  47
  48 -static void exynos4_mct_tick_clear(struct mct_clock_event_device *mevt)
  49 +static irqreturn_t exynos4_mct_tick_isr(int irq, void *dev_id)
  50  {
  51 +       struct mct_clock_event_device *mevt = dev_id;
  52 +       struct clock_event_device *evt = &mevt->evt;
  53 +
  54         /*
  55          * This is for supporting oneshot mode.
  56          * Mct would generate interrupt periodically
  57 @@ -430,16 +440,6 @@ static void exynos4_mct_tick_clear(struc
  58         if (!clockevent_state_periodic(&mevt->evt))
  59                 exynos4_mct_tick_stop(mevt);
  60
  61 -       /* Clear the MCT tick interrupt */
  62 -       if (readl_relaxed(reg_base + mevt->base + MCT_L_INT_CSTAT_OFFSET) & 1)
  63 -               exynos4_mct_write(0x1, mevt->base + MCT_L_INT_CSTAT_OFFSET);
  64 -}
  65 -
  66 -static irqreturn_t exynos4_mct_tick_isr(int irq, void *dev_id)
  67 -{
  68 -       struct mct_clock_event_device *mevt = dev_id;
  69 -       struct clock_event_device *evt = &mevt->evt;
  70 -
  71         exynos4_mct_tick_clear(mevt);
  72
  73         evt->event_handler(evt);