drm/nouveau: add function to wait until a callback returns true

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

2 files changed, 21 insertions, 0 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_drv.h b/drivers/gpu/drm/nouveau/nouveau_drv.h
index 06867055181e..0f0c5e59535f 100644
--- a/drivers/gpu/drm/nouveau/nouveau_drv.h
+++ b/drivers/gpu/drm/nouveau/nouveau_drv.h
@@ -833,6 +833,8 @@ extern bool nouveau_wait_eq(struct drm_device *, uint64_t timeout,
                             uint32_t reg, uint32_t mask, uint32_t val);
 extern bool nouveau_wait_ne(struct drm_device *, uint64_t timeout,
                             uint32_t reg, uint32_t mask, uint32_t val);
+extern bool nouveau_wait_cb(struct drm_device *, u64 timeout,
+                            bool (*cond)(void *), void *);
 extern bool nouveau_wait_for_idle(struct drm_device *);
 extern int  nouveau_card_init(struct drm_device *);
 
@@ -1457,6 +1459,8 @@ static inline void nv_wr08(struct drm_device *dev, unsigned reg, u8 val)
         nouveau_wait_eq(dev, 2000000000ULL, (reg), (mask), (val))
 #define nv_wait_ne(dev, reg, mask, val) \
         nouveau_wait_ne(dev, 2000000000ULL, (reg), (mask), (val))
+#define nv_wait_cb(dev, func, data) \
+        nouveau_wait_cb(dev, 2000000000ULL, (func), (data))
 
 /* PRAMIN access */
 static inline u32 nv_ri32(struct drm_device *dev, unsigned offset)
diff --git a/drivers/gpu/drm/nouveau/nouveau_state.c b/drivers/gpu/drm/nouveau/nouveau_state.c
index 3e7f3812bfcd..8dc73b6b8138 100644
--- a/drivers/gpu/drm/nouveau/nouveau_state.c
+++ b/drivers/gpu/drm/nouveau/nouveau_state.c
@@ -1200,6 +1200,23 @@ nouveau_wait_ne(struct drm_device *dev, uint64_t timeout,
         return false;
 }
 
+/* Wait until cond(data) == true, up until timeout has hit */
+bool
+nouveau_wait_cb(struct drm_device *dev, u64 timeout,
+                bool (*cond)(void *), void *data)
+{
+        struct drm_nouveau_private *dev_priv = dev->dev_private;
+        struct nouveau_timer_engine *ptimer = &dev_priv->engine.timer;
+        u64 start = ptimer->read(dev);
+
+        do {
+                if (cond(data) == true)
+                        return true;
+        } while (ptimer->read(dev) - start < timeout);
+
+        return false;
+}
+
 /* Waits for PGRAPH to go completely idle */
 bool nouveau_wait_for_idle(struct drm_device *dev)
 {