drm/vblank: Extract get_vblank_counter_and_timestamp()

We have three copies of the "read vblank counter and timestamp
in a loop" code. Consolidate to a single a function.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patch.msgid.link/20260323213645.10965-1-ville.syrjala@linux.intel.com
Reviewed-by: Suraj Kandpal <suraj.kandpal@intel.com>

diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c
index f78bf37f1e0a7fac95f48e1d21ea9d99653e71c4..f90fb2d13e423df5b627c860295e7da5b624aedb 100644 (file)
--- a/drivers/gpu/drm/drm_vblank.c
+++ b/drivers/gpu/drm/drm_vblank.c
@@ -236,6 +236,21 @@ static u32 __get_vblank_counter(struct drm_device *dev, unsigned int pipe)
        return drm_vblank_no_hw_counter(dev, pipe);
 }
 
+static bool get_vblank_counter_and_timestamp(struct drm_device *dev, unsigned int pipe,
+                                            u32 *cur_vblank, ktime_t *t_vblank,
+                                            bool in_vblank_irq)
+{
+       int count = DRM_TIMESTAMP_MAXRETRIES;
+       bool rc;
+
+       do {
+               *cur_vblank = __get_vblank_counter(dev, pipe);
+               rc = drm_get_last_vbltimestamp(dev, pipe, t_vblank, in_vblank_irq);
+       } while (*cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0);
+
+       return rc;
+}
+
 /*
  * Reset the stored timestamp for the current vblank count to correspond
  * to the last vblank occurred.
@@ -250,7 +265,6 @@ static void drm_reset_vblank_timestamp(struct drm_device *dev, unsigned int pipe
        u32 cur_vblank;
        bool rc;
        ktime_t t_vblank;
-       int count = DRM_TIMESTAMP_MAXRETRIES;
 
        spin_lock(&dev->vblank_time_lock);
 
@@ -258,10 +272,8 @@ static void drm_reset_vblank_timestamp(struct drm_device *dev, unsigned int pipe
         * sample the current counter to avoid random jumps
         * when drm_vblank_enable() applies the diff
         */
-       do {
-               cur_vblank = __get_vblank_counter(dev, pipe);
-               rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, false);
-       } while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0);
+       rc = get_vblank_counter_and_timestamp(dev, pipe, &cur_vblank,
+                                             &t_vblank, false);
 
        /*
         * Only reinitialize corresponding vblank timestamp if high-precision query
@@ -299,7 +311,6 @@ static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe,
        u32 cur_vblank, diff;
        bool rc;
        ktime_t t_vblank;
-       int count = DRM_TIMESTAMP_MAXRETRIES;
        int framedur_ns = vblank->framedur_ns;
        u32 max_vblank_count = drm_max_vblank_count(dev, pipe);
 
@@ -315,10 +326,8 @@ static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe,
         * updating its hardware counter while we are retrieving the
         * corresponding vblank timestamp.
         */
-       do {
-               cur_vblank = __get_vblank_counter(dev, pipe);
-               rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, in_vblank_irq);
-       } while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0);
+       rc = get_vblank_counter_and_timestamp(dev, pipe, &cur_vblank,
+                                             &t_vblank, in_vblank_irq);
 
        if (max_vblank_count) {
                /* trust the hw counter when it's around */
@@ -1543,7 +1552,6 @@ static void drm_vblank_restore(struct drm_device *dev, unsigned int pipe)
        int framedur_ns;
        u64 diff_ns;
        u32 cur_vblank, diff = 1;
-       int count = DRM_TIMESTAMP_MAXRETRIES;
        u32 max_vblank_count = drm_max_vblank_count(dev, pipe);
 
        if (drm_WARN_ON(dev, pipe >= dev->num_crtcs))
@@ -1558,10 +1566,8 @@ static void drm_vblank_restore(struct drm_device *dev, unsigned int pipe)
                      "Cannot compute missed vblanks without frame duration\n");
        framedur_ns = vblank->framedur_ns;
 
-       do {
-               cur_vblank = __get_vblank_counter(dev, pipe);
-               drm_get_last_vbltimestamp(dev, pipe, &t_vblank, false);
-       } while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0);
+       get_vblank_counter_and_timestamp(dev, pipe, &cur_vblank,
+                                        &t_vblank, false);
 
        diff_ns = ktime_to_ns(ktime_sub(t_vblank, vblank->time));
        if (framedur_ns)