DMA mask is typically set in nouveau_ttm_init(), but this function is called late during initialization and GK20A's instmem will have called DMA functions before this happens. Having a wrongly set DMA mask can result in the use of unneeded bounce buffers. Set it early to avoid this. Signed-off-by: Alexandre Courbot <acourbot@xxxxxxxxxx> --- Changes since v1: - Set mask in tegra.c instead of instmem, as suggested by Ben. drm/nouveau/nvkm/engine/device/tegra.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drm/nouveau/nvkm/engine/device/tegra.c b/drm/nouveau/nvkm/engine/device/tegra.c index 6d89416f0bc1..e1cd665aee2c 100644 --- a/drm/nouveau/nvkm/engine/device/tegra.c +++ b/drm/nouveau/nvkm/engine/device/tegra.c @@ -272,6 +272,15 @@ nvkm_device_tegra_new(const struct nvkm_device_tegra_func *func, if (IS_ERR(tdev->clk_pwr)) return PTR_ERR(tdev->clk_pwr); + /** + * The IOMMU bit defines the upper limit of the GPU-addressable space. + * This will be refined in nouveau_ttm_init but we need to do it early + * for instmem to behave properly + */ + ret = dma_set_mask(&pdev->dev, DMA_BIT_MASK(tdev->func->iommu_bit)); + if (ret) + return ret; + nvkm_device_tegra_probe_iommu(tdev); ret = nvkm_device_tegra_power_up(tdev); -- 2.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html