On some Zhaoxin platforms, xHCI will prefetch TRB for performance improvement. However this TRB prefetch mechanism may cross page boundary, which may access memory not belong to xHCI. In order to fix this issue, using two pages for TRB allocate and only the first page will be used.

The patch is scheduled to be submitted to the kernel mainline in 2021.

v1->v2: - Use quirks instead of vendor id.

Signed-off-by: LeoLiu-oc LeoLiu-oc@zhaoxin.com --- drivers/usb/host/xhci-mem.c | 10 ++++++++-- drivers/usb/host/xhci-pci.c | 5 +++++ drivers/usb/host/xhci.h | 1 + 3 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c index 9e87c282a743..aff1ccb94399 100644 --- a/drivers/usb/host/xhci-mem.c +++ b/drivers/usb/host/xhci-mem.c @@ -2450,8 +2450,14 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags) * and our use of dma addresses in the trb_address_map radix tree needs * TRB_SEGMENT_SIZE alignment, so we pick the greater alignment need. */ - xhci->segment_pool = dma_pool_create("xHCI ring segments", dev, - TRB_SEGMENT_SIZE, TRB_SEGMENT_SIZE, xhci->page_size); + /*With xHCI TRB prefetch patch:To fix cross page boundry access issue in IOV environment*/ + if (xhci->quirks == XHCI_ZHAOXIN_TRB_FETCH) { + xhci->segment_pool = dma_pool_create("xHCI ring segments", dev, + TRB_SEGMENT_SIZE*2, TRB_SEGMENT_SIZE*2, xhci->page_size*2); + } else { + xhci->segment_pool = dma_pool_create("xHCI ring segments", dev, + TRB_SEGMENT_SIZE, TRB_SEGMENT_SIZE, xhci->page_size); + }

/* See Table 46 and Note on Figure 55 */ xhci->device_pool = dma_pool_create("xHCI input/output contexts", dev, diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c index 6c6b29901c5e..798b660f2fd0 100644 --- a/drivers/usb/host/xhci-pci.c +++ b/drivers/usb/host/xhci-pci.c @@ -237,6 +237,11 @@ 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_ZHAOXIN && + (pdev->device == 0x9202 || + pdev->device == 0x9203)) + xhci->quirks |= XHCI_ZHAOXIN_TRB_FETCH; + if (pdev->vendor == PCI_VENDOR_ID_ASMEDIA && pdev->device == PCI_DEVICE_ID_ASMEDIA_1042_XHCI) xhci->quirks |= XHCI_BROKEN_STREAMS; diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index 069390a1f2ac..3ae8e25a2622 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -1874,6 +1874,7 @@ struct xhci_hcd { #define XHCI_SNPS_BROKEN_SUSPEND BIT_ULL(35) #define XHCI_ZHAOXIN_HOST BIT_ULL(36) #define XHCI_DISABLE_SPARSE BIT_ULL(38) +#define XHCI_ZHAOXIN_TRB_FETCH BIT_ULL(39)

unsigned int num_active_eps; unsigned int limit_active_eps;