Hi, On Wednesday 23 May 2018 11:11 PM, Marc Zyngier wrote: > Back around the 4.13 timeframe, we tried to address a rather bad issue > with the Renesas uPD72020x USB3 controller family. They have trouble > with the programming of the base addresses which tend to stick on XHCI > reset. This makes transitionning from 64bit to 32bit addresses > completely unsafe. This was observed on a fairly popular arm64 > platform (AMD Opteron 1100, which has all of its memory above 4GB). > > The fix was to perform a PCI reset of the device, but we have had > multiple reports that this generated regressions (the controller not > being usable after the patch was applied). > > This series reverts the problematic patch, and tries to address it in > a more constrained way. If the controller is behind an IOMMU (and only > in that case), we zero its base addresses before reseting it. In the > affected configuration, this has the effect of putting the device in a > state where the XHCI reset will be effective. > > It must be noted that in the absence of an IOMMU (and maybe even in > its presence), this device is completely unsafe, and may silently > corrupt memory. > > * From v1: > - Fixed stupid hunk misplacement, now properly moved back to patch 2 > - Converted all quirks to BIT_ULL() > > * From v2: > - Moved zeroing code to its own function > - Also perform the zeroing on hibernate > > Marc Zyngier (3): > xhci: Allow more than 32 quirks > xhci: Add quirk to zero 64bit registers on Renesas PCIe controllers > Revert "xhci: Reset Renesas uPD72020x USB controller for 32-bit DMA > issue" > > drivers/usb/host/pci-quirks.c | 20 ------------ > drivers/usb/host/pci-quirks.h | 1 - > drivers/usb/host/xhci-pci.c | 15 ++++----- > drivers/usb/host/xhci.c | 71 +++++++++++++++++++++++++++++++++++++++++-- > drivers/usb/host/xhci.h | 67 ++++++++++++++++++++-------------------- > 5 files changed, 108 insertions(+), 66 deletions(-) > Tested-by: Faiz Abbas <faiz_abbas@xxxxxx> Thanks, Faiz -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
