From: Rob Clark robdclark@chromium.org
[ Upstream commit 2311720a0182756f175fbf4afc1fb76ac487b587 ]
And while we are at it, let's start the fence counter close to the rollover point so that if issues slip in, they are more obvious.
Signed-off-by: Rob Clark robdclark@chromium.org Fixes: fde5de6cb461 ("drm/msm: move fence code to it's own file") Fixes: 5f3aee4ceb5b ("drm/msm: Handle fence rollover") Patchwork: https://patchwork.freedesktop.org/patch/489619/ Link: https://lore.kernel.org/r/20220615162435.3011793-1-robdclark@gmail.com [DB: fixed the conflict while applying the patch] Signed-off-by: Dmitry Baryshkov dmitry.baryshkov@linaro.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/msm/msm_fence.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/msm/msm_fence.c b/drivers/gpu/drm/msm/msm_fence.c index 38e3323bc232..a47e5837c528 100644 --- a/drivers/gpu/drm/msm/msm_fence.c +++ b/drivers/gpu/drm/msm/msm_fence.c @@ -28,6 +28,14 @@ msm_fence_context_alloc(struct drm_device *dev, volatile uint32_t *fenceptr, fctx->fenceptr = fenceptr; spin_lock_init(&fctx->spinlock);
+ /* + * Start out close to the 32b fence rollover point, so we can + * catch bugs with fence comparisons. + */ + fctx->last_fence = 0xffffff00; + fctx->completed_fence = fctx->last_fence; + *fctx->fenceptr = fctx->last_fence; + return fctx; }
@@ -52,7 +60,8 @@ void msm_update_fence(struct msm_fence_context *fctx, uint32_t fence) unsigned long flags;
spin_lock_irqsave(&fctx->spinlock, flags); - fctx->completed_fence = max(fence, fctx->completed_fence); + if (fence_after(fence, fctx->completed_fence)) + fctx->completed_fence = fence; spin_unlock_irqrestore(&fctx->spinlock, flags); }