drm/nv50: prevent (IB_PUT == IB_GET) for occurring unless idle



Should fix a DMA race condition I've never seen myself, but could be
the culprit in some random hangs that have been reported.

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

parent cd2fb2e9

drivers/gpu/drm/nouveau/nouveau_dma.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -214,7 +214,7 @@ nv50_dma_push_wait(struct nouveau_channel *chan, int count)

		chan->dma.ib_free = get - chan->dma.ib_put;
		if (chan->dma.ib_free <= 0)
		chan->dma.ib_free += chan->dma.ib_max + 1;
		chan->dma.ib_free += chan->dma.ib_max;
		}

		return 0;