[PATCH 07/23] drm: omapdrm: crtc: switch pending variable to atomic bitset

[Sebastian Reichel]

Having the pending variable available as atomic bit helps
with the later addition of manually updated display support.

Signed-off-by: Sebastian Reichel <sre at kernel.org>
---
 drivers/gpu/drm/omapdrm/omap_crtc.c | 31 +++++++++++++++++--------------
 1 file changed, 17 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/omapdrm/omap_crtc.c 
b/drivers/gpu/drm/omapdrm/omap_crtc.c
index 2ed0754ed19e..5ef27664bcfa 100644
--- a/drivers/gpu/drm/omapdrm/omap_crtc.c
+++ b/drivers/gpu/drm/omapdrm/omap_crtc.c
@@ -28,6 +28,11 @@

 #define to_omap_crtc(x) container_of(x, struct omap_crtc, base)

+enum omap_crtc_state {
+       crtc_enabled    = 0,
+       crtc_pending    = 1
+};
+
 struct omap_crtc {
        struct drm_crtc base;

@@ -49,7 +54,7 @@ struct omap_crtc {

        bool ignore_digit_sync_lost;

-       bool pending;
+       unsigned long state;
        wait_queue_head_t pending_wait;
 };

@@ -81,7 +86,7 @@ int omap_crtc_wait_pending(struct drm_crtc *crtc)
        struct omap_crtc *omap_crtc = to_omap_crtc(crtc);

        return wait_event_timeout(omap_crtc->pending_wait,
-                                 !omap_crtc->pending,
+                                 !test_bit(crtc_pending, &omap_crtc->state),
                                  msecs_to_jiffies(50));
 }

@@ -311,10 +316,8 @@ static void omap_crtc_vblank_irq(struct omap_drm_irq *irq, 
uint32_t irqstatus)

        __omap_irq_unregister(dev, &omap_crtc->vblank_irq);

-       rmb();
-       WARN_ON(!omap_crtc->pending);
-       omap_crtc->pending = false;
-       wmb();
+       if (!test_and_clear_bit(crtc_pending, &omap_crtc->state))
+               dev_warn(dev->dev, "pending bit was not set in vblank irq");

        /* wake up userspace */
        omap_crtc_complete_page_flip(&omap_crtc->base);
@@ -351,13 +354,12 @@ static bool omap_crtc_mode_fixup(struct drm_crtc *crtc,
 static void omap_crtc_enable(struct drm_crtc *crtc)
 {
        struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
+       struct drm_device *dev = crtc->dev;

        DBG("%s", omap_crtc->name);

-       rmb();
-       WARN_ON(omap_crtc->pending);
-       omap_crtc->pending = true;
-       wmb();
+       if (test_and_set_bit(crtc_pending, &omap_crtc->state))
+               dev_warn(dev->dev, "crtc enable while pending bit set!");

        omap_irq_register(crtc->dev, &omap_crtc->vblank_irq);

@@ -397,6 +399,7 @@ static void omap_crtc_atomic_flush(struct drm_crtc *crtc,
                                   struct drm_crtc_state *old_crtc_state)
 {
        struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
+       struct drm_device *dev = crtc->dev;

        WARN_ON(omap_crtc->vblank_irq.registered);

@@ -404,10 +407,8 @@ static void omap_crtc_atomic_flush(struct drm_crtc *crtc,

                DBG("%s: GO", omap_crtc->name);

-               rmb();
-               WARN_ON(omap_crtc->pending);
-               omap_crtc->pending = true;
-               wmb();
+               if (test_and_set_bit(crtc_pending, &omap_crtc->state))
+                       dev_warn(dev->dev, "atomic flush while pending bit 
set!");

                dispc_mgr_go(omap_crtc->channel);
                omap_irq_register(crtc->dev, &omap_crtc->vblank_irq);
@@ -509,6 +510,8 @@ struct drm_crtc *omap_crtc_init(struct drm_device *dev,

        init_waitqueue_head(&omap_crtc->pending_wait);

+       omap_crtc->state = 0;
+
        omap_crtc->channel = channel;
        omap_crtc->name = channel_names[channel];

-- 
2.7.0