From bcb60d438547355b8f9ad48645909139b64d3482 Mon Sep 17 00:00:00 2001 From: Huacai Chen Date: Fri, 28 Mar 2025 12:00:59 +0800 Subject: [PATCH] USB: OHCI: Add quirk for LS7A OHCI controller (rev 0x02) The OHCI controller (rev 0x02) under LS7A PCI host has a hardware flaw. MMIO register with offset 0x60/0x64 is treated as legacy PS2-compatible keyboard/mouse interface, which confuse the OHCI controller. Since OHCI only use a 4KB BAR resource indeed, the LS7A OHCI controller's 32KB BAR is wrapped around (the second 4KB BAR space is the same as the first 4KB internally). So we can add an 4KB offset (0x1000) to the OHCI registers (from the PCI BAR resource) as a quirk. Cc: stable Suggested-by: Bjorn Helgaas Reviewed-by: Alan Stern Tested-by: Mingcong Bai Signed-off-by: Huacai Chen Link: https://lore.kernel.org/r/20250328040059.3672979-1-chenhuacai@loongson.cn Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/ohci-pci.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/drivers/usb/host/ohci-pci.c b/drivers/usb/host/ohci-pci.c index 900ea0d368e03..9f0a6b27e47cb 100644 --- a/drivers/usb/host/ohci-pci.c +++ b/drivers/usb/host/ohci-pci.c @@ -165,6 +165,25 @@ static int ohci_quirk_amd700(struct usb_hcd *hcd) return 0; } +static int ohci_quirk_loongson(struct usb_hcd *hcd) +{ + struct pci_dev *pdev = to_pci_dev(hcd->self.controller); + + /* + * Loongson's LS7A OHCI controller (rev 0x02) has a + * flaw. MMIO register with offset 0x60/64 is treated + * as legacy PS2-compatible keyboard/mouse interface. + * Since OHCI only use 4KB BAR resource, LS7A OHCI's + * 32KB BAR is wrapped around (the 2nd 4KB BAR space + * is the same as the 1st 4KB internally). So add 4KB + * offset (0x1000) to the OHCI registers as a quirk. + */ + if (pdev->revision == 0x2) + hcd->regs += SZ_4K; /* SZ_4K = 0x1000 */ + + return 0; +} + static int ohci_quirk_qemu(struct usb_hcd *hcd) { struct ohci_hcd *ohci = hcd_to_ohci(hcd); @@ -224,6 +243,10 @@ static const struct pci_device_id ohci_pci_quirks[] = { PCI_DEVICE(PCI_VENDOR_ID_ATI, 0x4399), .driver_data = (unsigned long)ohci_quirk_amd700, }, + { + PCI_DEVICE(PCI_VENDOR_ID_LOONGSON, 0x7a24), + .driver_data = (unsigned long)ohci_quirk_loongson, + }, { .vendor = PCI_VENDOR_ID_APPLE, .device = 0x003f, -- 2.39.5