From 91b1b79a0336e096dd1a695d1e885f71ac1ef973 Mon Sep 17 00:00:00 2001 From: Jonathan Bell Date: Thu, 11 Jul 2019 17:55:43 +0100 Subject: [PATCH] xhci: add quirk for host controllers that don't update endpoint DCS Seen on a VLI VL805 PCIe to USB controller. For non-stream endpoints at least, if the xHC halts on a particular TRB due to an error then the DCS field in the Out Endpoint Context maintained by the hardware is not updated with the current cycle state. Using the quirk XHCI_EP_CTX_BROKEN_DCS and instead fetch the DCS bit from the TRB that the xHC stopped on. See: https://github.com/raspberrypi/linux/issues/3060 Signed-off-by: Jonathan Bell --- drivers/usb/host/xhci-pci.c | 4 +++- drivers/usb/host/xhci-ring.c | 26 +++++++++++++++++++++++++- drivers/usb/host/xhci.h | 1 + 3 files changed, 29 insertions(+), 2 deletions(-) diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c index 84da8406d5b42..551ef6445c6b2 100644 --- a/drivers/usb/host/xhci-pci.c +++ b/drivers/usb/host/xhci-pci.c @@ -269,8 +269,10 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci) pdev->device == 0x3432) xhci->quirks |= XHCI_BROKEN_STREAMS; - if (pdev->vendor == PCI_VENDOR_ID_VIA && pdev->device == 0x3483) + if (pdev->vendor == PCI_VENDOR_ID_VIA && pdev->device == 0x3483) { xhci->quirks |= XHCI_LPM_SUPPORT; + xhci->quirks |= XHCI_EP_CTX_BROKEN_DCS; + } if (pdev->vendor == PCI_VENDOR_ID_ASMEDIA && pdev->device == PCI_DEVICE_ID_ASMEDIA_1042_XHCI) diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 167dae117f738..f7504a78e2453 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -533,7 +533,10 @@ void xhci_find_new_dequeue_state(struct xhci_hcd *xhci, struct xhci_virt_ep *ep = &dev->eps[ep_index]; struct xhci_ring *ep_ring; struct xhci_segment *new_seg; + struct xhci_segment *halted_seg = NULL; union xhci_trb *new_deq; + union xhci_trb *halted_trb; + int index = 0; dma_addr_t addr; u64 hw_dequeue; bool cycle_found = false; @@ -571,7 +574,28 @@ void xhci_find_new_dequeue_state(struct xhci_hcd *xhci, hw_dequeue = xhci_get_hw_deq(xhci, dev, ep_index, stream_id); new_seg = ep_ring->deq_seg; new_deq = ep_ring->dequeue; - state->new_cycle_state = hw_dequeue & 0x1; + + /* + * Quirk: xHC write-back of the DCS field in the hardware dequeue + * pointer is wrong - use the cycle state of the TRB pointed to by + * the dequeue pointer. + */ + if (xhci->quirks & XHCI_EP_CTX_BROKEN_DCS && + !(ep->ep_state & EP_HAS_STREAMS)) + halted_seg = trb_in_td(xhci, cur_td->start_seg, + cur_td->first_trb, cur_td->last_trb, + hw_dequeue & ~0xf, false); + if (halted_seg) { + index = ((dma_addr_t)(hw_dequeue & ~0xf) - halted_seg->dma) / + sizeof(*halted_trb); + halted_trb = &halted_seg->trbs[index]; + state->new_cycle_state = halted_trb->generic.field[3] & 0x1; + xhci_dbg(xhci, "Endpoint DCS = %d TRB index = %d cycle = %d\n", + (u8)(hw_dequeue & 0x1), index, + state->new_cycle_state); + } else { + state->new_cycle_state = hw_dequeue & 0x1; + } state->stream_id = stream_id; /* diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index d90c0d5df3b37..0aa1ccede6b13 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -1879,6 +1879,7 @@ struct xhci_hcd { #define XHCI_SKIP_PHY_INIT BIT_ULL(37) #define XHCI_DISABLE_SPARSE BIT_ULL(38) #define XHCI_SG_TRB_CACHE_SIZE_QUIRK BIT_ULL(39) +#define XHCI_EP_CTX_BROKEN_DCS BIT_ULL(40) unsigned int num_active_eps; unsigned int limit_active_eps;