On Thu, Oct 10, 2019 at 3:50 PM Tomasz Figa <tfiga@xxxxxxxxxxxx> wrote: > > MediaTek XHCI host controller does not support 64-bit addressing despite > the AC64 bit of HCCPARAMS1 register being set. The platform-specific > glue sets the DMA mask to 32 bits on its own, but it has no effect, > because xhci_gen_setup() overrides it according to hardware > capabilities. > > Use the XHCI_NO_64BIT_SUPPORT quirk to tell the XHCI core to force > 32-bit DMA mask instead. > > Signed-off-by: Tomasz Figa <tfiga@xxxxxxxxxxxx> Can we add a Fixes: tag for stable backports? (after addressing the other comments of course) > --- > drivers/usb/host/xhci-mtk.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/drivers/usb/host/xhci-mtk.c b/drivers/usb/host/xhci-mtk.c > index b18a6baef204a..4d101d52cc11b 100644 > --- a/drivers/usb/host/xhci-mtk.c > +++ b/drivers/usb/host/xhci-mtk.c > @@ -395,6 +395,11 @@ static void xhci_mtk_quirks(struct device *dev, struct xhci_hcd *xhci) > xhci->quirks |= XHCI_SPURIOUS_SUCCESS; > if (mtk->lpm_support) > xhci->quirks |= XHCI_LPM_SUPPORT; > + /* > + * MTK host controller does not support 64-bit addressing, despite > + * having the AC64 bit of the HCCPARAMS1 register set. > + */ > + xhci->quirks |= XHCI_NO_64BIT_SUPPORT; > } > > /* called during probe() after chip reset completes */ > @@ -488,11 +493,6 @@ static int xhci_mtk_probe(struct platform_device *pdev) > goto disable_clk; > } > > - /* Initialize dma_mask and coherent_dma_mask to 32-bits */ > - ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32)); > - if (ret) > - goto disable_clk; > - > hcd = usb_create_hcd(driver, dev, dev_name(dev)); > if (!hcd) { > ret = -ENOMEM; > -- > 2.23.0.581.g78d2f28ef7-goog >