Hi, Yoshihiro Shimoda <[email protected]> writes: > [ text/plain ] > Hi Mathias, > > Would you review this patch? > This patch could be applied into the latest usb.git / usb-next branch. > > Best regards, > Yoshihiro Shimoda > >> -----Original Message----- >> From: Yoshihiro Shimoda >> Sent: Tuesday, February 16, 2016 12:26 PM >> To: [email protected]; [email protected] >> Cc: [email protected]; [email protected]; Yoshihiro >> Shimoda <[email protected]> >> Subject: [PATCH] usb: host: xhci-plat: fix cannot work if R-Car Gen2/3 run >> on above 4GB phys >> >> On xHCI controllers of R-Car Gen2 and Gen3, the AC64 bit (bit 0) of >> HCCPARAMS1 is set to 1. However, these SoCs don't support 64-bit address >> memory pointers. So, this driver should call dma_set_coherent_mask(dev, >> DMA_BIT_MASK(32)) in xhci_gen_setup(). Otherwise, the xHCI controller >> will be died after a usb device is connected if R-Car Gen2/3 run on above >> 4GB physical memory environment. >> >> This patch adds clearing the AC64 bit of xhci->hcc_params in the >> xhci_plat_quirks() to fix the issue. >> >> Signed-off-by: Yoshihiro Shimoda <[email protected]> >> --- >> drivers/usb/host/xhci-plat.c | 13 +++++++++++++ >> 1 file changed, 13 insertions(+) >> >> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c >> index d39d6bf..047fb6a 100644 >> --- a/drivers/usb/host/xhci-plat.c >> +++ b/drivers/usb/host/xhci-plat.c >> @@ -39,12 +39,25 @@ static const struct xhci_driver_overrides >> xhci_plat_overrides __initconst = { >> >> static void xhci_plat_quirks(struct device *dev, struct xhci_hcd *xhci) >> { >> + struct usb_hcd *hcd = xhci_to_hcd(xhci); >> + >> /* >> * As of now platform drivers don't provide MSI support so we ensure >> * here that the generic code does not try to make a pci_dev from our >> * dev struct in order to setup MSI >> */ >> xhci->quirks |= XHCI_PLAT; >> + >> + /* >> + * On R-Car Gen2 and Gen3, the AC64 bit (bit 0) of HCCPARAMS1 is set >> + * to 1. However, these SoCs don't support 64-bit address memory >> + * pointers. So, this driver clears the AC64 bit of xhci->hcc_params >> + * to call dma_set_coherent_mask(dev, DMA_BIT_MASK(32)) in >> + * xhci_gen_setup(). >> + */ >> + if (xhci_plat_type_is(hcd, XHCI_PLAT_TYPE_RENESAS_RCAR_GEN2) || >> + xhci_plat_type_is(hcd, XHCI_PLAT_TYPE_RENESAS_RCAR_GEN3)) >> + xhci->hcc_params &= ~BIT(0); /* clear HCC_64BIT_ADDR >> */
Mathias, of course, has the final saying; but I feel that, just like any other quirk, this should be setting a flag in xhci->quirks and xhci core would clear hcc_params. The reason is that if we ever need this on some PCIe card, we won't have to shuffle code around. -- balbi
signature.asc
Description: PGP signature
