dmaengine: rcar-dmac: Widen DMA mask to 40 bits

By default, the DMA mask covers only the low 32-bit address space, which
causes SWIOTLB on arm64 to fall back to a bounce buffer for DMA
transfers involving memory outside the 32-bit address space.

The R-Car DMA controller hardware supports a 40-bit address space, hence
widen the DMA mask to 40 bits to actually make use of this feature.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
This commit is contained in:
Geert Uytterhoeven 2017-02-13 12:00:26 +01:00 committed by Vinod Koul
parent c429ceb1e1
commit dc312349e8
1 changed files with 1 additions and 0 deletions

View File

@ -1716,6 +1716,7 @@ static int rcar_dmac_probe(struct platform_device *pdev)
dmac->dev = &pdev->dev;
platform_set_drvdata(pdev, dmac);
dma_set_mask_and_coherent(dmac->dev, DMA_BIT_MASK(40));
ret = rcar_dmac_parse_of(&pdev->dev, dmac);
if (ret < 0)