From 9c1aa36efdae0c97c6d7285187b0573fc1793552 Mon Sep 17 00:00:00 2001 From: Mathias Nyman Date: Thu, 12 Mar 2020 16:45:11 +0200 Subject: [PATCH] xhci: Show host status when watchdog triggers and host is assumed dead. Additional debugging to show xHC USBSTS register when stop endpoint command watchdog triggers and host is assumed dead. useful to know the current status before the controller is stopped by the xhci driver and everything is released and freed. Signed-off-by: Mathias Nyman Link: https://lore.kernel.org/r/20200312144517.1593-4-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-ring.c | 4 ++++ drivers/usb/host/xhci.h | 29 +++++++++++++++++++++++++++++ 2 files changed, 33 insertions(+) diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index efcddc0..ba512b2 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -955,6 +955,7 @@ void xhci_stop_endpoint_command_watchdog(struct timer_list *t) struct xhci_virt_ep *ep = from_timer(ep, t, stop_cmd_timer); struct xhci_hcd *xhci = ep->xhci; unsigned long flags; + u32 usbsts; spin_lock_irqsave(&xhci->lock, flags); @@ -965,8 +966,11 @@ void xhci_stop_endpoint_command_watchdog(struct timer_list *t) xhci_dbg(xhci, "Stop EP timer raced with cmd completion, exit"); return; } + usbsts = readl(&xhci->op_regs->status); xhci_warn(xhci, "xHCI host not responding to stop endpoint command.\n"); + xhci_warn(xhci, "USBSTS:%s\n", xhci_decode_usbsts(usbsts)); + ep->ep_state &= ~EP_STOP_CMD_PENDING; xhci_halt(xhci); diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index 685180e..3ff199c 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -2589,6 +2589,35 @@ static inline const char *xhci_decode_portsc(u32 portsc) return str; } +static inline const char *xhci_decode_usbsts(u32 usbsts) +{ + static char str[256]; + int ret = 0; + + if (usbsts == ~(u32)0) + return " 0xffffffff"; + if (usbsts & STS_HALT) + ret += sprintf(str + ret, " HCHalted"); + if (usbsts & STS_FATAL) + ret += sprintf(str + ret, " HSE"); + if (usbsts & STS_EINT) + ret += sprintf(str + ret, " EINT"); + if (usbsts & STS_PORT) + ret += sprintf(str + ret, " PCD"); + if (usbsts & STS_SAVE) + ret += sprintf(str + ret, " SSS"); + if (usbsts & STS_RESTORE) + ret += sprintf(str + ret, " RSS"); + if (usbsts & STS_SRE) + ret += sprintf(str + ret, " SRE"); + if (usbsts & STS_CNR) + ret += sprintf(str + ret, " CNR"); + if (usbsts & STS_HCE) + ret += sprintf(str + ret, " HCE"); + + return str; +} + static inline const char *xhci_decode_doorbell(u32 slot, u32 doorbell) { static char str[256]; -- 2.7.4