From linux-usb-devel-admin@lists.sourceforge.net Tue May 16 05:23:39 2006 From: David Brownell Cc: Andrew Morton Message-Id: <200605121849.09003.david-b@pacbell.net> Subject: USB: OHCI avoids root hub timer polling Date: Fri, 4 Aug 2006 11:31:55 -0700 This teaches OHCI to use the root hub status change (RHSC) IRQ, bypassing root hub timers most of the time and switching over to the "new" root hub polling scheme. It's complicated by the fact that implementations of OHCI trigger and ack that IRQ differently (the spec is vague there). Avoiding root hub timers helps mechanisms like "dynamic tick" leave the CPU in lowpower modes for longer intervals. Signed-off-by: David Brownell Signed-off-by: Greg Kroah-Hartman --- --- drivers/usb/host/ohci-at91.c | 2 - drivers/usb/host/ohci-au1xxx.c | 5 -- drivers/usb/host/ohci-dbg.c | 5 ++ drivers/usb/host/ohci-ep93xx.c | 1 drivers/usb/host/ohci-hcd.c | 41 +++++++++++++++++++----- drivers/usb/host/ohci-hub.c | 67 +++++++++++++++++++++++++++------------- drivers/usb/host/ohci-lh7a404.c | 5 -- drivers/usb/host/ohci-omap.c | 5 ++ drivers/usb/host/ohci-pci.c | 5 ++ drivers/usb/host/ohci-ppc-soc.c | 1 drivers/usb/host/ohci-pxa27x.c | 1 drivers/usb/host/ohci-s3c2410.c | 1 drivers/usb/host/ohci-sa1111.c | 5 -- 13 files changed, 99 insertions(+), 45 deletions(-) --- gregkh-2.6.orig/drivers/usb/host/ohci-at91.c +++ gregkh-2.6/drivers/usb/host/ohci-at91.c @@ -239,7 +239,7 @@ static const struct hc_driver ohci_at91_ */ .hub_status_data = ohci_hub_status_data, .hub_control = ohci_hub_control, - + .hub_irq_enable = ohci_rhsc_enable, #ifdef CONFIG_PM .bus_suspend = ohci_bus_suspend, .bus_resume = ohci_bus_resume, --- gregkh-2.6.orig/drivers/usb/host/ohci-au1xxx.c +++ gregkh-2.6/drivers/usb/host/ohci-au1xxx.c @@ -268,10 +268,6 @@ static const struct hc_driver ohci_au1xx * basic lifecycle operations */ .start = ohci_au1xxx_start, -#ifdef CONFIG_PM - /* suspend: ohci_au1xxx_suspend, -- tbd */ - /* resume: ohci_au1xxx_resume, -- tbd */ -#endif /*CONFIG_PM*/ .stop = ohci_stop, /* @@ -291,6 +287,7 @@ static const struct hc_driver ohci_au1xx */ .hub_status_data = ohci_hub_status_data, .hub_control = ohci_hub_control, + .hub_irq_enable = ohci_rhsc_enable, #ifdef CONFIG_PM .bus_suspend = ohci_bus_suspend, .bus_resume = ohci_bus_resume, --- gregkh-2.6.orig/drivers/usb/host/ohci-dbg.c +++ gregkh-2.6/drivers/usb/host/ohci-dbg.c @@ -667,6 +667,11 @@ show_registers (struct class_device *cla size -= temp; next += temp; + temp = scnprintf (next, size, "hub poll timer %s\n", + ohci_to_hcd(ohci)->poll_rh ? "ON" : "off"); + size -= temp; + next += temp; + /* roothub */ ohci_dump_roothub (ohci, 1, &next, &size); --- gregkh-2.6.orig/drivers/usb/host/ohci-ep93xx.c +++ gregkh-2.6/drivers/usb/host/ohci-ep93xx.c @@ -134,6 +134,7 @@ static struct hc_driver ohci_ep93xx_hc_d .get_frame_number = ohci_get_frame, .hub_status_data = ohci_hub_status_data, .hub_control = ohci_hub_control, + .hub_irq_enable = ohci_rhsc_enable, #ifdef CONFIG_PM .bus_suspend = ohci_bus_suspend, .bus_resume = ohci_bus_resume, --- gregkh-2.6.orig/drivers/usb/host/ohci-hcd.c +++ gregkh-2.6/drivers/usb/host/ohci-hcd.c @@ -101,7 +101,7 @@ #include "../core/hcd.h" -#define DRIVER_VERSION "2005 April 22" +#define DRIVER_VERSION "2006 August 04" #define DRIVER_AUTHOR "Roman Weissgaerber, David Brownell" #define DRIVER_DESC "USB 1.1 'Open' Host Controller (OHCI) Driver" @@ -110,9 +110,10 @@ #undef OHCI_VERBOSE_DEBUG /* not always helpful */ /* For initializing controller (mask in an HCFS mode too) */ -#define OHCI_CONTROL_INIT OHCI_CTRL_CBSR +#define OHCI_CONTROL_INIT OHCI_CTRL_CBSR #define OHCI_INTR_INIT \ - (OHCI_INTR_MIE | OHCI_INTR_UE | OHCI_INTR_RD | OHCI_INTR_WDH) + (OHCI_INTR_MIE | OHCI_INTR_RHSC | OHCI_INTR_UE \ + | OHCI_INTR_RD | OHCI_INTR_WDH) #ifdef __hppa__ /* On PA-RISC, PDC can leave IR set incorrectly; ignore it there. */ @@ -128,6 +129,8 @@ static const char hcd_name [] = "ohci_hcd"; +#define STATECHANGE_DELAY msecs_to_jiffies(300) + #include "ohci.h" static void ohci_dump (struct ohci_hcd *ohci, int verbose); @@ -446,7 +449,6 @@ static int ohci_init (struct ohci_hcd *o disable (ohci); ohci->regs = hcd->regs; - ohci->next_statechange = jiffies; /* REVISIT this BIOS handshake is now moved into PCI "quirks", and * was never needed for most non-PCI systems ... remove the code? @@ -637,10 +639,14 @@ retry: return -EOVERFLOW; } - /* start controller operations */ + /* use rhsc irqs after khubd is fully initialized */ + hcd->poll_rh = 1; + hcd->uses_new_polling = 1; + + /* start controller operations */ ohci->hc_control &= OHCI_CTRL_RWC; - ohci->hc_control |= OHCI_CONTROL_INIT | OHCI_USB_OPER; - ohci_writel (ohci, ohci->hc_control, &ohci->regs->control); + ohci->hc_control |= OHCI_CONTROL_INIT | OHCI_USB_OPER; + ohci_writel (ohci, ohci->hc_control, &ohci->regs->control); hcd->state = HC_STATE_RUNNING; /* wake on ConnectStatusChange, matching external hubs */ @@ -648,7 +654,7 @@ retry: /* Choose the interrupts we care about now, others later on demand */ mask = OHCI_INTR_INIT; - ohci_writel (ohci, mask, &ohci->regs->intrstatus); + ohci_writel (ohci, ~0, &ohci->regs->intrstatus); ohci_writel (ohci, mask, &ohci->regs->intrenable); /* handle root hub init quirks ... */ @@ -672,6 +678,7 @@ retry: // flush those writes (void) ohci_readl (ohci, &ohci->regs->control); + ohci->next_statechange = jiffies + STATECHANGE_DELAY; spin_unlock_irq (&ohci->lock); // POTPGT delay is bits 24-31, in 2 ms units. @@ -709,7 +716,23 @@ static irqreturn_t ohci_irq (struct usb_ /* interrupt for some other device? */ } else if ((ints &= ohci_readl (ohci, ®s->intrenable)) == 0) { return IRQ_NOTMINE; - } + } + + /* NOTE: vendors didn't always make the same implementation + * choices for RHSC. Sometimes it triggers on an edge (like + * setting and maybe clearing a port status change bit); and + * it's level-triggered on other silicon, active until khubd + * clears all active port status change bits. Poll by timer + * til it's fully debounced and the difference won't matter. + */ + if (ints & OHCI_INTR_RHSC) { + ohci_vdbg (ohci, "rhsc\n"); + ohci_writel (ohci, OHCI_INTR_RHSC, ®s->intrdisable); + hcd->poll_rh = 1; + ohci->next_statechange = jiffies + STATECHANGE_DELAY; + ohci_writel (ohci, OHCI_INTR_RHSC, ®s->intrstatus); + usb_hcd_poll_rh_status(hcd); + } if (ints & OHCI_INTR_UE) { disable (ohci); --- gregkh-2.6.orig/drivers/usb/host/ohci-hub.c +++ gregkh-2.6/drivers/usb/host/ohci-hub.c @@ -36,6 +36,14 @@ /*-------------------------------------------------------------------------*/ +/* hcd->hub_irq_enable() */ +static void ohci_rhsc_enable (struct usb_hcd *hcd) +{ + struct ohci_hcd *ohci = hcd_to_ohci (hcd); + + ohci_writel (ohci, OHCI_INTR_RHSC, &ohci->regs->intrenable); +} + #ifdef CONFIG_PM #define OHCI_SCHED_ENABLES \ @@ -123,6 +131,9 @@ static int ohci_bus_suspend (struct usb_ /* no resumes until devices finish suspending */ ohci->next_statechange = jiffies + msecs_to_jiffies (5); + /* no timer polling */ + hcd->poll_rh = 0; + done: /* external suspend vs self autosuspend ... same effect */ if (status == 0) @@ -256,8 +267,8 @@ static int ohci_bus_resume (struct usb_h /* TRSMRCY */ msleep (10); - /* keep it alive for ~5x suspend + resume costs */ - ohci->next_statechange = jiffies + msecs_to_jiffies (250); + /* keep it alive for more than ~5x suspend + resume costs */ + ohci->next_statechange = jiffies + STATECHANGE_DELAY; /* maybe turn schedules back on */ enables = 0; @@ -302,9 +313,10 @@ ohci_hub_status_data (struct usb_hcd *hc { struct ohci_hcd *ohci = hcd_to_ohci (hcd); int i, changed = 0, length = 1; - int can_suspend = device_may_wakeup(&hcd->self.root_hub->dev); + int can_suspend; unsigned long flags; + can_suspend = device_may_wakeup(&hcd->self.root_hub->dev); spin_lock_irqsave (&ohci->lock, flags); /* handle autosuspended root: finish resuming before @@ -339,6 +351,10 @@ ohci_hub_status_data (struct usb_hcd *hc for (i = 0; i < ohci->num_ports; i++) { u32 status = roothub_portstatus (ohci, i); + /* can't autosuspend with active ports */ + if ((status & RH_PS_PES) && !(status & RH_PS_PSS)) + can_suspend = 0; + if (status & (RH_PS_CSC | RH_PS_PESC | RH_PS_PSSC | RH_PS_OCIC | RH_PS_PRSC)) { changed = 1; @@ -348,32 +364,41 @@ ohci_hub_status_data (struct usb_hcd *hc buf [1] |= 1 << (i - 7); continue; } + } - /* can suspend if no ports are enabled; or if all all - * enabled ports are suspended AND remote wakeup is on. - */ - if (!(status & RH_PS_CCS)) - continue; - if ((status & RH_PS_PSS) && can_suspend) - continue; + /* after root hub changes, stop polling after debouncing + * for a while and maybe kicking in autosuspend + */ + if (changed) { + ohci->next_statechange = jiffies + STATECHANGE_DELAY; can_suspend = 0; + } else if (time_before (jiffies, ohci->next_statechange)) { + can_suspend = 0; + } else { +#ifdef CONFIG_PM + can_suspend = can_suspend + && !ohci->ed_rm_list + && ((OHCI_CTRL_HCFS | OHCI_SCHED_ENABLES) + & ohci->hc_control) + == OHCI_USB_OPER; +#endif + if (hcd->uses_new_polling) { + hcd->poll_rh = 0; + /* use INTR_RHSC iff INTR_RD won't apply */ + if (!can_suspend) + ohci_writel (ohci, OHCI_INTR_RHSC, + &ohci->regs->intrenable); + } } + done: spin_unlock_irqrestore (&ohci->lock, flags); -#ifdef CONFIG_PM - /* save power by suspending idle root hubs; +#ifdef CONFIG_PM + /* save power by autosuspending idle root hubs; * INTR_RD wakes us when there's work */ - if (can_suspend - && !changed - && !ohci->ed_rm_list - && ((OHCI_CTRL_HCFS | OHCI_SCHED_ENABLES) - & ohci->hc_control) - == OHCI_USB_OPER - && time_after (jiffies, ohci->next_statechange) - && usb_trylock_device (hcd->self.root_hub) == 0 - ) { + if (can_suspend && usb_trylock_device (hcd->self.root_hub) == 0) { ohci_vdbg (ohci, "autosuspend\n"); (void) ohci_bus_suspend (hcd); usb_unlock_device (hcd->self.root_hub); --- gregkh-2.6.orig/drivers/usb/host/ohci-lh7a404.c +++ gregkh-2.6/drivers/usb/host/ohci-lh7a404.c @@ -173,10 +173,6 @@ static const struct hc_driver ohci_lh7a4 * basic lifecycle operations */ .start = ohci_lh7a404_start, -#ifdef CONFIG_PM - /* suspend: ohci_lh7a404_suspend, -- tbd */ - /* resume: ohci_lh7a404_resume, -- tbd */ -#endif /*CONFIG_PM*/ .stop = ohci_stop, /* @@ -196,6 +192,7 @@ static const struct hc_driver ohci_lh7a4 */ .hub_status_data = ohci_hub_status_data, .hub_control = ohci_hub_control, + .hub_irq_enable = ohci_rhsc_enable, #ifdef CONFIG_PM .bus_suspend = ohci_bus_suspend, .bus_resume = ohci_bus_resume, --- gregkh-2.6.orig/drivers/usb/host/ohci-omap.c +++ gregkh-2.6/drivers/usb/host/ohci-omap.c @@ -382,8 +382,10 @@ ohci_omap_start (struct usb_hcd *hcd) int ret; config = hcd->self.controller->platform_data; - if (config->otg || config->rwc) + if (config->otg || config->rwc) { + ohci->hc_control = OHCI_CTRL_RWC; writel(OHCI_CTRL_RWC, &ohci->regs->control); + } if ((ret = ohci_run (ohci)) < 0) { dev_err(hcd->self.controller, "can't start\n"); @@ -429,6 +431,7 @@ static const struct hc_driver ohci_omap_ */ .hub_status_data = ohci_hub_status_data, .hub_control = ohci_hub_control, + .hub_irq_enable = ohci_rhsc_enable, #ifdef CONFIG_PM .bus_suspend = ohci_bus_suspend, .bus_resume = ohci_bus_resume, --- gregkh-2.6.orig/drivers/usb/host/ohci-pci.c +++ gregkh-2.6/drivers/usb/host/ohci-pci.c @@ -176,11 +176,13 @@ static const struct hc_driver ohci_pci_h */ .reset = ohci_pci_reset, .start = ohci_pci_start, + .stop = ohci_stop, + #ifdef CONFIG_PM + /* these suspend/resume entries are for upstream PCI glue ONLY */ .suspend = ohci_pci_suspend, .resume = ohci_pci_resume, #endif - .stop = ohci_stop, /* * managing i/o requests and associated device resources @@ -199,6 +201,7 @@ static const struct hc_driver ohci_pci_h */ .hub_status_data = ohci_hub_status_data, .hub_control = ohci_hub_control, + .hub_irq_enable = ohci_rhsc_enable, #ifdef CONFIG_PM .bus_suspend = ohci_bus_suspend, .bus_resume = ohci_bus_resume, --- gregkh-2.6.orig/drivers/usb/host/ohci-ppc-soc.c +++ gregkh-2.6/drivers/usb/host/ohci-ppc-soc.c @@ -166,6 +166,7 @@ static const struct hc_driver ohci_ppc_s */ .hub_status_data = ohci_hub_status_data, .hub_control = ohci_hub_control, + .hub_irq_enable = ohci_rhsc_enable, #ifdef CONFIG_PM .bus_suspend = ohci_bus_suspend, .bus_resume = ohci_bus_resume, --- gregkh-2.6.orig/drivers/usb/host/ohci-pxa27x.c +++ gregkh-2.6/drivers/usb/host/ohci-pxa27x.c @@ -288,6 +288,7 @@ static const struct hc_driver ohci_pxa27 */ .hub_status_data = ohci_hub_status_data, .hub_control = ohci_hub_control, + .hub_irq_enable = ohci_rhsc_enable, #ifdef CONFIG_PM .bus_suspend = ohci_bus_suspend, .bus_resume = ohci_bus_resume, --- gregkh-2.6.orig/drivers/usb/host/ohci-s3c2410.c +++ gregkh-2.6/drivers/usb/host/ohci-s3c2410.c @@ -465,6 +465,7 @@ static const struct hc_driver ohci_s3c24 */ .hub_status_data = ohci_s3c2410_hub_status_data, .hub_control = ohci_s3c2410_hub_control, + .hub_irq_enable = ohci_rhsc_enable, #ifdef CONFIG_PM .bus_suspend = ohci_bus_suspend, .bus_resume = ohci_bus_resume, --- gregkh-2.6.orig/drivers/usb/host/ohci-sa1111.c +++ gregkh-2.6/drivers/usb/host/ohci-sa1111.c @@ -212,10 +212,6 @@ static const struct hc_driver ohci_sa111 * basic lifecycle operations */ .start = ohci_sa1111_start, -#ifdef CONFIG_PM - /* suspend: ohci_sa1111_suspend, -- tbd */ - /* resume: ohci_sa1111_resume, -- tbd */ -#endif .stop = ohci_stop, /* @@ -235,6 +231,7 @@ static const struct hc_driver ohci_sa111 */ .hub_status_data = ohci_hub_status_data, .hub_control = ohci_hub_control, + .hub_irq_enable = ohci_rhsc_enable, #ifdef CONFIG_PM .bus_suspend = ohci_bus_suspend, .bus_resume = ohci_bus_resume,