[EXT] Re: [PATCH 1/1] PCI: layerscape: Set 64-bit DMA mask

Frank Li frank.li at nxp.com
Tue Feb 14 13:50:51 PST 2023


> >
> > +     /* set 64-bit DMA mask and coherent DMA mask */
> > +     if (dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64)))
> > +             dev_warn(dev, "Failed to set 64-bit DMA mask.\n");
> 
> Isn't this mandatory? Why not dev_err_probe and return the error?

I don't think it is mandatory. If failure, dma will use swiotlb. 
Just an additional memcpy involved. 

Frank Li

> 
> --Sean
> 
> >       platform_set_drvdata(pdev, pcie);
> >
> >       ret = dw_pcie_ep_init(&pci->ep);



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