drm/msm: spin helper

Helper macro to simplify places where we need to poll with timeout
waiting for gpu.

Signed-off-by: Rob Clark <robdclark@gmail.com>

3 files changed, 32 insertions, 38 deletions

diff --git a/drivers/gpu/drm/msm/adreno/a3xx_gpu.c b/drivers/gpu/drm/msm/adreno/a3xx_gpu.c
index 8b6fb847789e..59ed7620fc1a 100644
--- a/drivers/gpu/drm/msm/adreno/a3xx_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/a3xx_gpu.c
@@ -326,21 +326,13 @@ static void a3xx_destroy(struct msm_gpu *gpu)
 
 static void a3xx_idle(struct msm_gpu *gpu)
 {
-        unsigned long t;
-
         /* wait for ringbuffer to drain: */
         adreno_idle(gpu);
 
-        t = jiffies + ADRENO_IDLE_TIMEOUT;
-
         /* then wait for GPU to finish: */
-        do {
-                uint32_t rbbm_status = gpu_read(gpu, REG_A3XX_RBBM_STATUS);
-                if (!(rbbm_status & A3XX_RBBM_STATUS_GPU_BUSY))
-                        return;
-        } while(time_before(jiffies, t));
-
-        DRM_ERROR("timeout waiting for %s to idle!\n", gpu->name);
+        if (spin_until(!(gpu_read(gpu, REG_A3XX_RBBM_STATUS) &
+                        A3XX_RBBM_STATUS_GPU_BUSY)))
+                DRM_ERROR("%s: timeout waiting for GPU to idle!\n", gpu->name);
 
         /* TODO maybe we need to reset GPU here to recover from hang? */
 }
diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.c b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
index cf6eb976dda7..7a11563379b8 100644
--- a/drivers/gpu/drm/msm/adreno/adreno_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
@@ -225,19 +225,11 @@ void adreno_flush(struct msm_gpu *gpu)
 void adreno_idle(struct msm_gpu *gpu)
 {
         struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
-        uint32_t rptr, wptr = get_wptr(gpu->rb);
-        unsigned long t;
-
-        t = jiffies + ADRENO_IDLE_TIMEOUT;
-
-        /* then wait for CP to drain ringbuffer: */
-        do {
-                rptr = adreno_gpu->memptrs->rptr;
-                if (rptr == wptr)
-                        return;
-        } while(time_before(jiffies, t));
+        uint32_t wptr = get_wptr(gpu->rb);
 
-        DRM_ERROR("%s: timeout waiting to drain ringbuffer!\n", gpu->name);
+        /* wait for CP to drain ringbuffer: */
+        if (spin_until(adreno_gpu->memptrs->rptr == wptr))
+                DRM_ERROR("%s: timeout waiting to drain ringbuffer!\n", gpu->name);
 
         /* TODO maybe we need to reset GPU here to recover from hang? */
 }
@@ -278,22 +270,19 @@ void adreno_dump(struct msm_gpu *gpu)
 
 }
 
-void adreno_wait_ring(struct msm_gpu *gpu, uint32_t ndwords)
+static uint32_t ring_freewords(struct msm_gpu *gpu)
 {
         struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
-        uint32_t freedwords;
-        unsigned long t = jiffies + ADRENO_IDLE_TIMEOUT;
-        do {
-                uint32_t size = gpu->rb->size / 4;
-                uint32_t wptr = get_wptr(gpu->rb);
-                uint32_t rptr = adreno_gpu->memptrs->rptr;
-                freedwords = (rptr + (size - 1) - wptr) % size;
-
-                if (time_after(jiffies, t)) {
-                        DRM_ERROR("%s: timeout waiting for ringbuffer space\n", gpu->name);
-                        break;
-                }
-        } while(freedwords < ndwords);
+        uint32_t size = gpu->rb->size / 4;
+        uint32_t wptr = get_wptr(gpu->rb);
+        uint32_t rptr = adreno_gpu->memptrs->rptr;
+        return (rptr + (size - 1) - wptr) % size;
+}
+
+void adreno_wait_ring(struct msm_gpu *gpu, uint32_t ndwords)
+{
+        if (spin_until(ring_freewords(gpu) >= ndwords))
+                DRM_ERROR("%s: timeout waiting for ringbuffer space\n", gpu->name);
 }
 
 static const char *iommu_ports[] = {
diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.h b/drivers/gpu/drm/msm/adreno/adreno_gpu.h
index e16200ddc60b..63c36ce33020 100644
--- a/drivers/gpu/drm/msm/adreno/adreno_gpu.h
+++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.h
@@ -76,7 +76,20 @@ struct adreno_platform_config {
 #endif
 };
 
-#define ADRENO_IDLE_TIMEOUT (20 * 1000)
+#define ADRENO_IDLE_TIMEOUT msecs_to_jiffies(1000)
+
+#define spin_until(X) ({                                   \
+        int __ret = -ETIMEDOUT;                            \
+        unsigned long __t = jiffies + ADRENO_IDLE_TIMEOUT; \
+        do {                                               \
+                if (X) {                                   \
+                        __ret = 0;                         \
+                        break;                             \
+                }                                          \
+        } while (time_before(jiffies, __t));               \
+        __ret;                                             \
+})
+
 
 static inline bool adreno_is_a3xx(struct adreno_gpu *gpu)
 {