Add a kernel parameter that replaces the USB_RESUME_TIMEOUT and other hardcoded delay numbers with the USB spec minimums. The USB subsystem currently uses heavily padded values for TDRSMDN and TRSTRCY. This patch keeps the current values by default, but if the kernel is booted with usb_timing_minimum=1 they are set to the spec minimums with no padding. The result is significant performance improvement in usb device resume. Use this only if you know your USB hardware and device setup can handle the spec minimums. Example analyze_suspend runs are provided here showing the benefits: https://01.org/suspendresume/blogs/tebrandt/2016/usb-resume-optimization-using-spec-minimum-delays Signed-off-by: Todd Brandt <todd.e.brandt@xxxxxxxxxxxxxxx> --- v2 changes: - moved the core code from hub.c to usb.c - changed the module param to a core param - param name is now usb_timing_minimum - configured isp1362-hcd and ohci-hub to use the new values Documentation/admin-guide/kernel-parameters.txt | 7 +++++++ drivers/usb/core/hub.c | 12 ++++++------ drivers/usb/core/usb.c | 15 +++++++++++++++ drivers/usb/dwc2/hcd.c | 2 +- drivers/usb/host/ehci-hcd.c | 4 ++-- drivers/usb/host/ehci-hub.c | 6 +++--- drivers/usb/host/fotg210-hcd.c | 2 +- drivers/usb/host/isp116x-hcd.c | 2 +- drivers/usb/host/isp1362-hcd.c | 2 +- drivers/usb/host/ohci-hub.c | 2 +- drivers/usb/host/oxu210hp-hcd.c | 4 ++-- drivers/usb/host/r8a66597-hcd.c | 2 +- drivers/usb/host/sl811-hcd.c | 2 +- drivers/usb/host/uhci-hub.c | 6 +++--- drivers/usb/host/xhci-hub.c | 6 +++--- drivers/usb/host/xhci-ring.c | 2 +- drivers/usb/isp1760/isp1760-hcd.c | 2 +- drivers/usb/musb/musb_core.c | 6 +++--- drivers/usb/musb/musb_virthub.c | 2 +- include/linux/usb.h | 23 ++++++++++++++++++++++- 20 files changed, 76 insertions(+), 33 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index be2d6d0..210ab72 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -4024,6 +4024,13 @@ unknown_nmi_panic [X86] Cause panic on unknown NMI. + usb_timing_minimum= + Set USB timing values to USB 2.0 spec minimums (default 0 = off). + This removes any padding added to the values to accommodate + older or troublesome hardware. This will reduce usb resume + time. Use this only if you know your USB hardware and device + setup can handle the spec minimums. + usbcore.authorized_default= [USB] Default USB device authorization: (default -1 = authorized except for wireless USB, diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 143454e..10c0bea 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -2841,7 +2841,7 @@ static int hub_port_reset(struct usb_hub *hub, int port1, done: if (status == 0) { /* TRSTRCY = 10 ms; plus some extra */ - msleep(10 + 40); + msleep(usb_timing.trstrcy); if (udev) { struct usb_hcd *hcd = bus_to_hcd(udev->bus); @@ -3433,10 +3433,10 @@ int usb_port_resume(struct usb_device *udev, pm_message_t msg) if (status) { dev_dbg(&port_dev->dev, "can't resume, status %d\n", status); } else { - /* drive resume for USB_RESUME_TIMEOUT msec */ + /* drive resume for TDRSMDN msec */ dev_dbg(&udev->dev, "usb %sresume\n", (PMSG_IS_AUTO(msg) ? "auto-" : "")); - msleep(USB_RESUME_TIMEOUT); + msleep(usb_timing.tdrsmdn); /* Virtual root hubs can trigger on GET_PORT_STATUS to * stop resume signaling. Then finish the resume @@ -3445,7 +3445,7 @@ int usb_port_resume(struct usb_device *udev, pm_message_t msg) status = hub_port_status(hub, port1, &portstatus, &portchange); /* TRSMRCY = 10 msec */ - msleep(10); + msleep(usb_timing.trsmrcy); } SuspendCleared: @@ -3531,7 +3531,7 @@ static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port, if (udev) { /* TRSMRCY = 10 msec */ - msleep(10); + msleep(usb_timing.trsmrcy); usb_unlock_port(port_dev); ret = usb_remote_wakeup(udev); @@ -4108,7 +4108,7 @@ static void hub_usb3_port_prepare_disable(struct usb_hub *hub, ret = hub_set_port_link_state(hub, port_dev->portnum, USB_SS_PORT_LS_U0); if (!ret) { - msleep(USB_RESUME_TIMEOUT); + msleep(usb_timing.tdrsmdn); ret = usb_disable_remote_wakeup(udev); } if (ret) diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c index a2ccc69f..7859e8a 100644 --- a/drivers/usb/core/usb.c +++ b/drivers/usb/core/usb.c @@ -74,6 +74,15 @@ MODULE_PARM_DESC(autosuspend, "default autosuspend delay"); #define usb_autosuspend_delay 0 #endif +static bool usb_timing_minimum; +core_param(usb_timing_minimum, usb_timing_minimum, bool, 0644); + +struct _usb_timing_config usb_timing = { + .tdrsmdn = USB_TIMING_TDRSMDN_DEF, + .trsmrcy = USB_TIMING_TRSMRCY_DEF, + .trstrcy = USB_TIMING_TRSTRCY_DEF +}; +EXPORT_SYMBOL_GPL(usb_timing); /** * usb_find_alt_setting() - Given a configuration, find the alternate setting @@ -1070,6 +1079,12 @@ static int __init usb_init(void) } usb_init_pool_max(); + if (usb_timing_minimum) { + usb_timing.tdrsmdn = USB_TIMING_TDRSMDN_MIN; + usb_timing.trsmrcy = USB_TIMING_TRSMRCY_MIN; + usb_timing.trstrcy = USB_TIMING_TRSTRCY_MIN; + } + retval = usb_debugfs_init(); if (retval) goto out; diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c index 911c3b3..652f908 100644 --- a/drivers/usb/dwc2/hcd.c +++ b/drivers/usb/dwc2/hcd.c @@ -3388,7 +3388,7 @@ static void dwc2_port_resume(struct dwc2_hsotg *hsotg) dwc2_writel(hprt0, hsotg->regs + HPRT0); spin_unlock_irqrestore(&hsotg->lock, flags); - msleep(USB_RESUME_TIMEOUT); + msleep(usb_timing.tdrsmdn); spin_lock_irqsave(&hsotg->lock, flags); hprt0 = dwc2_read_hprt0(hsotg); diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c index 0630648..ccf6e45 100644 --- a/drivers/usb/host/ehci-hcd.c +++ b/drivers/usb/host/ehci-hcd.c @@ -807,12 +807,12 @@ static irqreturn_t ehci_irq (struct usb_hcd *hcd) ehci->reset_done[i] == 0)) continue; - /* start USB_RESUME_TIMEOUT msec resume signaling from + /* start TDRSMDN msec resume signaling from * this port, and make hub_wq collect * PORT_STAT_C_SUSPEND to stop that signaling. */ ehci->reset_done[i] = jiffies + - msecs_to_jiffies(USB_RESUME_TIMEOUT); + msecs_to_jiffies(usb_timing.tdrsmdn); set_bit(i, &ehci->resuming_ports); ehci_dbg (ehci, "port %d remote wakeup\n", i + 1); usb_hcd_start_port_resume(&hcd->self, i); diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c index df169c8..ca0e98d7 100644 --- a/drivers/usb/host/ehci-hub.c +++ b/drivers/usb/host/ehci-hub.c @@ -485,12 +485,12 @@ static int ehci_bus_resume (struct usb_hcd *hcd) } /* - * msleep for USB_RESUME_TIMEOUT ms only if code is trying to resume + * msleep for TDRSMDN ms only if code is trying to resume * port */ if (resume_needed) { spin_unlock_irq(&ehci->lock); - msleep(USB_RESUME_TIMEOUT); + msleep(usb_timing.tdrsmdn); spin_lock_irq(&ehci->lock); if (ehci->shutdown) goto shutdown; @@ -966,7 +966,7 @@ int ehci_hub_control( temp &= ~PORT_WAKE_BITS; ehci_writel(ehci, temp | PORT_RESUME, status_reg); ehci->reset_done[wIndex] = jiffies - + msecs_to_jiffies(USB_RESUME_TIMEOUT); + + msecs_to_jiffies(usb_timing.tdrsmdn); set_bit(wIndex, &ehci->resuming_ports); usb_hcd_start_port_resume(&hcd->self, wIndex); break; diff --git a/drivers/usb/host/fotg210-hcd.c b/drivers/usb/host/fotg210-hcd.c index 66efa9a..3e87703 100644 --- a/drivers/usb/host/fotg210-hcd.c +++ b/drivers/usb/host/fotg210-hcd.c @@ -1544,7 +1544,7 @@ static int fotg210_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue, /* resume signaling for 20 msec */ fotg210_writel(fotg210, temp | PORT_RESUME, status_reg); fotg210->reset_done[wIndex] = jiffies - + msecs_to_jiffies(USB_RESUME_TIMEOUT); + + msecs_to_jiffies(usb_timing.tdrsmdn); break; case USB_PORT_FEAT_C_SUSPEND: clear_bit(wIndex, &fotg210->port_c_suspend); diff --git a/drivers/usb/host/isp116x-hcd.c b/drivers/usb/host/isp116x-hcd.c index d089b3f..a71ffb2 100644 --- a/drivers/usb/host/isp116x-hcd.c +++ b/drivers/usb/host/isp116x-hcd.c @@ -1491,7 +1491,7 @@ static int isp116x_bus_resume(struct usb_hcd *hcd) spin_unlock_irq(&isp116x->lock); hcd->state = HC_STATE_RESUMING; - msleep(USB_RESUME_TIMEOUT); + msleep(usb_timing.tdrsmdn); /* Go operational */ spin_lock_irq(&isp116x->lock); diff --git a/drivers/usb/host/isp1362-hcd.c b/drivers/usb/host/isp1362-hcd.c index 0f2b4b3..916f715 100644 --- a/drivers/usb/host/isp1362-hcd.c +++ b/drivers/usb/host/isp1362-hcd.c @@ -1896,7 +1896,7 @@ static int isp1362_bus_resume(struct usb_hcd *hcd) isp1362_write_reg32(isp1362_hcd, HCCONTROL, isp1362_hcd->hc_control); spin_unlock_irqrestore(&isp1362_hcd->lock, flags); /* TRSMRCY */ - msleep(10); + msleep(usb_timing.trsmrcy); /* keep it alive for ~5x suspend + resume costs */ isp1362_hcd->next_statechange = jiffies + msecs_to_jiffies(250); diff --git a/drivers/usb/host/ohci-hub.c b/drivers/usb/host/ohci-hub.c index ed678c17..43f8106 100644 --- a/drivers/usb/host/ohci-hub.c +++ b/drivers/usb/host/ohci-hub.c @@ -256,7 +256,7 @@ __acquires(ohci->lock) /* TRSMRCY */ if (!autostopped) { - msleep (10); + msleep(usb_timing.trsmrcy); spin_lock_irq (&ohci->lock); } /* now ohci->lock is always held and irqs are always disabled */ diff --git a/drivers/usb/host/oxu210hp-hcd.c b/drivers/usb/host/oxu210hp-hcd.c index 4e4d601..c3ebb93 100644 --- a/drivers/usb/host/oxu210hp-hcd.c +++ b/drivers/usb/host/oxu210hp-hcd.c @@ -2493,12 +2493,12 @@ static irqreturn_t oxu210_hcd_irq(struct usb_hcd *hcd) || oxu->reset_done[i] != 0) continue; - /* start USB_RESUME_TIMEOUT resume signaling from this + /* start TDRSMDN resume signaling from this * port, and make hub_wq collect PORT_STAT_C_SUSPEND to * stop that signaling. */ oxu->reset_done[i] = jiffies + - msecs_to_jiffies(USB_RESUME_TIMEOUT); + msecs_to_jiffies(usb_timing.tdrsmdn); oxu_dbg(oxu, "port %d remote wakeup\n", i + 1); mod_timer(&hcd->rh_timer, oxu->reset_done[i]); } diff --git a/drivers/usb/host/r8a66597-hcd.c b/drivers/usb/host/r8a66597-hcd.c index bfa7fa3..50492f1 100644 --- a/drivers/usb/host/r8a66597-hcd.c +++ b/drivers/usb/host/r8a66597-hcd.c @@ -2298,7 +2298,7 @@ static int r8a66597_bus_resume(struct usb_hcd *hcd) rh->port &= ~USB_PORT_STAT_SUSPEND; rh->port |= USB_PORT_STAT_C_SUSPEND << 16; r8a66597_mdfy(r8a66597, RESUME, RESUME | UACT, dvstctr_reg); - msleep(USB_RESUME_TIMEOUT); + msleep(usb_timing.tdrsmdn); r8a66597_mdfy(r8a66597, UACT, RESUME | UACT, dvstctr_reg); } diff --git a/drivers/usb/host/sl811-hcd.c b/drivers/usb/host/sl811-hcd.c index fd2a114..26bfc84 100644 --- a/drivers/usb/host/sl811-hcd.c +++ b/drivers/usb/host/sl811-hcd.c @@ -1259,7 +1259,7 @@ sl811h_hub_control( sl811_write(sl811, SL11H_CTLREG1, sl811->ctrl1); mod_timer(&sl811->timer, jiffies - + msecs_to_jiffies(USB_RESUME_TIMEOUT)); + + msecs_to_jiffies(usb_timing.tdrsmdn)); break; case USB_PORT_FEAT_POWER: port_power(sl811, 0); diff --git a/drivers/usb/host/uhci-hub.c b/drivers/usb/host/uhci-hub.c index ece9e37..89af729 100644 --- a/drivers/usb/host/uhci-hub.c +++ b/drivers/usb/host/uhci-hub.c @@ -166,7 +166,7 @@ static void uhci_check_ports(struct uhci_hcd *uhci) /* Port received a wakeup request */ set_bit(port, &uhci->resuming_ports); uhci->ports_timeout = jiffies + - msecs_to_jiffies(USB_RESUME_TIMEOUT); + msecs_to_jiffies(usb_timing.tdrsmdn); usb_hcd_start_port_resume( &uhci_to_hcd(uhci)->self, port); @@ -339,7 +339,7 @@ static int uhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue, /* USB v2.0 7.1.7.5 */ uhci->ports_timeout = jiffies + - msecs_to_jiffies(USB_RESUME_TIMEOUT); + msecs_to_jiffies(usb_timing.trstrcy); break; case USB_PORT_FEAT_POWER: /* UHCI has no power switching */ @@ -382,7 +382,7 @@ static int uhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue, else /* USB v2.0 7.1.7.7 */ uhci->ports_timeout = jiffies + - msecs_to_jiffies(20); + msecs_to_jiffies(usb_timing.tdrsmdn); } break; case USB_PORT_FEAT_C_SUSPEND: diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c index 0ef1690..571fb5a 100644 --- a/drivers/usb/host/xhci-hub.c +++ b/drivers/usb/host/xhci-hub.c @@ -760,7 +760,7 @@ static u32 xhci_get_port_status(struct usb_hcd *hcd, * start resume timing */ unsigned long timeout = jiffies + - msecs_to_jiffies(USB_RESUME_TIMEOUT); + msecs_to_jiffies(usb_timing.tdrsmdn); set_bit(wIndex, &bus_state->resuming_ports); bus_state->resume_done[wIndex] = timeout; @@ -1166,7 +1166,7 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue, xhci_set_link_state(xhci, port_array, wIndex, XDEV_RESUME); spin_unlock_irqrestore(&xhci->lock, flags); - msleep(USB_RESUME_TIMEOUT); + msleep(usb_timing.tdrsmdn); spin_lock_irqsave(&xhci->lock, flags); xhci_set_link_state(xhci, port_array, wIndex, XDEV_U0); @@ -1447,7 +1447,7 @@ int xhci_bus_resume(struct usb_hcd *hcd) if (need_usb2_u3_exit) { spin_unlock_irqrestore(&xhci->lock, flags); - msleep(USB_RESUME_TIMEOUT); + msleep(usb_timing.tdrsmdn); spin_lock_irqsave(&xhci->lock, flags); } diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index bdf6b13..7627e7b 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -1607,7 +1607,7 @@ static void handle_port_status(struct xhci_hcd *xhci, &bus_state->resuming_ports)) { xhci_dbg(xhci, "resume HS port %d\n", port_id); bus_state->resume_done[faked_port_index] = jiffies + - msecs_to_jiffies(USB_RESUME_TIMEOUT); + msecs_to_jiffies(usb_timing.tdrsmdn); set_bit(faked_port_index, &bus_state->resuming_ports); mod_timer(&hcd->rh_timer, bus_state->resume_done[faked_port_index]); diff --git a/drivers/usb/isp1760/isp1760-hcd.c b/drivers/usb/isp1760/isp1760-hcd.c index ac31d19..dd3b4e9 100644 --- a/drivers/usb/isp1760/isp1760-hcd.c +++ b/drivers/usb/isp1760/isp1760-hcd.c @@ -1869,7 +1869,7 @@ static int isp1760_hub_control(struct usb_hcd *hcd, u16 typeReq, reg_write32(hcd->regs, HC_PORTSC1, temp | PORT_RESUME); priv->reset_done = jiffies + - msecs_to_jiffies(USB_RESUME_TIMEOUT); + msecs_to_jiffies(usb_timing.tdrsmdn); } break; case USB_PORT_FEAT_C_SUSPEND: diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c index 9e22646..e344db9 100644 --- a/drivers/usb/musb/musb_core.c +++ b/drivers/usb/musb/musb_core.c @@ -593,7 +593,7 @@ static irqreturn_t musb_stage0_irq(struct musb *musb, u8 int_usb, (USB_PORT_STAT_C_SUSPEND << 16) | MUSB_PORT_STAT_RESUME; musb->rh_timer = jiffies - + msecs_to_jiffies(USB_RESUME_TIMEOUT); + + msecs_to_jiffies(usb_timing.tdrsmdn); musb->need_finish_resume = 1; musb->xceiv->otg->state = OTG_STATE_A_HOST; @@ -2711,7 +2711,7 @@ static int musb_resume(struct device *dev) if (musb->need_finish_resume) { musb->need_finish_resume = 0; schedule_delayed_work(&musb->finish_resume_work, - msecs_to_jiffies(USB_RESUME_TIMEOUT)); + msecs_to_jiffies(usb_timing.tdrsmdn)); } /* @@ -2767,7 +2767,7 @@ static int musb_runtime_resume(struct device *dev) if (musb->need_finish_resume) { musb->need_finish_resume = 0; schedule_delayed_work(&musb->finish_resume_work, - msecs_to_jiffies(USB_RESUME_TIMEOUT)); + msecs_to_jiffies(usb_timing.tdrsmdn)); } spin_lock_irqsave(&musb->lock, flags); diff --git a/drivers/usb/musb/musb_virthub.c b/drivers/usb/musb/musb_virthub.c index 0b45954..053e896 100644 --- a/drivers/usb/musb/musb_virthub.c +++ b/drivers/usb/musb/musb_virthub.c @@ -134,7 +134,7 @@ void musb_port_suspend(struct musb *musb, bool do_suspend) musb->port1_status |= MUSB_PORT_STAT_RESUME; schedule_delayed_work(&musb->finish_resume_work, - msecs_to_jiffies(USB_RESUME_TIMEOUT)); + msecs_to_jiffies(usb_timing.tdrsmdn)); } } diff --git a/include/linux/usb.h b/include/linux/usb.h index 7e68259..620bfbb 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -233,8 +233,29 @@ void usb_put_intf(struct usb_interface *intf); * In order to avoid both conditions, we're using a 40 ms resume timeout, which * should cope with both LPJ calibration errors and devices not following every * detail of the USB Specification. + * + * struct _usb_timing_config - USB timing value settings + * @tdrsmdn: TDRSMDN resume signal time 7.1.7.7 + * @trsmrcy; TRSMRCY resume recovery time 7.1.7.7 + * @trstrcy; TRSTRCY reset recovery time 7.1.7.5 + * + * These timing values are defined in the USB 2.0 spec sec 7.3.2 table 7-13 + * Thir default values have been padded for various reasons and this config + * allows the system to use different values. */ -#define USB_RESUME_TIMEOUT 40 /* ms */ +#define USB_TIMING_TDRSMDN_MIN 20 +#define USB_TIMING_TRSMRCY_MIN 10 +#define USB_TIMING_TRSTRCY_MIN 0 +#define USB_TIMING_TDRSMDN_DEF 40 +#define USB_TIMING_TRSMRCY_DEF 10 +#define USB_TIMING_TRSTRCY_DEF 50 + +struct _usb_timing_config { + unsigned int tdrsmdn; /* resume signal time 20ms - infinity */ + unsigned int trsmrcy; /* resume recovery time 0ms - 10ms */ + unsigned int trstrcy; /* reset recovery time 0ms - infinity*/ +}; +extern struct _usb_timing_config usb_timing; /** * struct usb_interface_cache - long-term representation of a device interface -- 2.1.4 -- 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
