| Message ID | 1633677970-10619-1-git-send-email-zhuyinbo@loongson.cn (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v3] usb: ohci: add check for host controller functional states | expand |
On Fri, Oct 08, 2021 at 03:26:10PM +0800, Yinbo Zhu wrote: > The usb states of ohci controller include UsbOperational, UsbReset, > UsbSuspend and UsbResume. Among them, only the UsbOperational state > supports launching the start of frame for host controller according > the ohci protocol spec, but in S3/S4 press test procedure, it may Nobody reading this will know what "S3/S4 press test procedure" means. You have to explain it, or use a different name that people will understand. > happen that the start of frame was launched in other usb states and > cause ohci works abnormally then kernel will allways report rcu > call trace. This patch was to add check for host controller > functional states and if it is not UsbOperational state that need > set INTR_SF in intrdisable register to ensure SOF Token generation > was been disabled. This doesn't make sense. You already mentioned that only the UsbOperational state supports sending start-of-frame packets. So if the controller is in a different state then it won't send these packets, whether INTR_SF is enabled or not. What problem are you really trying to solve? > Signed-off-by: Yinbo Zhu <zhuyinbo@loongson.cn> > --- > Change in v3: > Rework the commit information. > Move the patch code change to lower down position in ohci_irq. > > > drivers/usb/host/ohci-hcd.c | 13 ++++++++++--- > 1 file changed, 10 insertions(+), 3 deletions(-) > > diff --git a/drivers/usb/host/ohci-hcd.c b/drivers/usb/host/ohci-hcd.c > index 1f5e693..87aa9bb 100644 > --- a/drivers/usb/host/ohci-hcd.c > +++ b/drivers/usb/host/ohci-hcd.c > @@ -879,7 +879,8 @@ static irqreturn_t ohci_irq (struct usb_hcd *hcd) > { > struct ohci_hcd *ohci = hcd_to_ohci (hcd); > struct ohci_regs __iomem *regs = ohci->regs; > - int ints; > + int ints, ctl; > + Extra blank line not needed. > > /* Read interrupt status (and flush pending writes). We ignore the > * optimization of checking the LSB of hcca->done_head; it doesn't > @@ -969,9 +970,15 @@ static irqreturn_t ohci_irq (struct usb_hcd *hcd) > * when there's still unlinking to be done (next frame). > */ > ohci_work(ohci); > - if ((ints & OHCI_INTR_SF) != 0 && !ohci->ed_rm_list > - && ohci->rh_state == OHCI_RH_RUNNING) > + > + ctl = ohci_readl(ohci, ®s->control); > + Blank lines not needed. > + if (((ints & OHCI_INTR_SF) != 0 && !ohci->ed_rm_list > + && ohci->rh_state == OHCI_RH_RUNNING) || > + ((ctl & OHCI_CTRL_HCFS) != OHCI_USB_OPER)) { > ohci_writel (ohci, OHCI_INTR_SF, ®s->intrdisable); > + (void)ohci_readl(ohci, ®s->intrdisable); > + } This is definitely wrong. You must not turn off SF interrupts when ed_rm_list is non-NULL. If you do, the driver will not be able to finish unlinking URBs. Alan Stern
在 2021/10/8 下午10:26, Alan Stern 写道: > On Fri, Oct 08, 2021 at 03:26:10PM +0800, Yinbo Zhu wrote: >> The usb states of ohci controller include UsbOperational, UsbReset, >> UsbSuspend and UsbResume. Among them, only the UsbOperational state >> supports launching the start of frame for host controller according >> the ohci protocol spec, but in S3/S4 press test procedure, it may > Nobody reading this will know what "S3/S4 press test procedure" means. > You have to explain it, or use a different name that people will > understand. okay, I got it. >> happen that the start of frame was launched in other usb states and >> cause ohci works abnormally then kernel will allways report rcu >> call trace. This patch was to add check for host controller >> functional states and if it is not UsbOperational state that need >> set INTR_SF in intrdisable register to ensure SOF Token generation >> was been disabled. > This doesn't make sense. You already mentioned that only the > UsbOperational state supports sending start-of-frame packets. So if the > controller is in a different state then it won't send these packets, > whether INTR_SF is enabled or not. > > What problem are you really trying to solve? Only UsbOperational state supports sending start-of-frame packets, but in fact, in S3/S4 press test procedure, usb in non-UsbOperational state that send start-of-frame packets but hc driver doesn't deal with this frame. and hc will allways lauched the SOF for finishing the frame, the cpu will hand this sof interrupt and doesn't deal with time interrupt that will cause rcu call trace then system doesn't suspend to memory/disk. >> Signed-off-by: Yinbo Zhu <zhuyinbo@loongson.cn> >> --- >> Change in v3: >> Rework the commit information. >> Move the patch code change to lower down position in ohci_irq. >> >> >> drivers/usb/host/ohci-hcd.c | 13 ++++++++++--- >> 1 file changed, 10 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/usb/host/ohci-hcd.c b/drivers/usb/host/ohci-hcd.c >> index 1f5e693..87aa9bb 100644 >> --- a/drivers/usb/host/ohci-hcd.c >> +++ b/drivers/usb/host/ohci-hcd.c >> @@ -879,7 +879,8 @@ static irqreturn_t ohci_irq (struct usb_hcd *hcd) >> { >> struct ohci_hcd *ohci = hcd_to_ohci (hcd); >> struct ohci_regs __iomem *regs = ohci->regs; >> - int ints; >> + int ints, ctl; >> + > Extra blank line not needed. > >> >> /* Read interrupt status (and flush pending writes). We ignore the >> * optimization of checking the LSB of hcca->done_head; it doesn't >> @@ -969,9 +970,15 @@ static irqreturn_t ohci_irq (struct usb_hcd *hcd) >> * when there's still unlinking to be done (next frame). >> */ >> ohci_work(ohci); >> - if ((ints & OHCI_INTR_SF) != 0 && !ohci->ed_rm_list >> - && ohci->rh_state == OHCI_RH_RUNNING) >> + >> + ctl = ohci_readl(ohci, ®s->control); >> + > Blank lines not needed. > >> + if (((ints & OHCI_INTR_SF) != 0 && !ohci->ed_rm_list >> + && ohci->rh_state == OHCI_RH_RUNNING) || >> + ((ctl & OHCI_CTRL_HCFS) != OHCI_USB_OPER)) { >> ohci_writel (ohci, OHCI_INTR_SF, ®s->intrdisable); >> + (void)ohci_readl(ohci, ®s->intrdisable); >> + } > This is definitely wrong. You must not turn off SF interrupts when > ed_rm_list is non-NULL. If you do, the driver will not be able to > finish unlinking URBs. > > Alan Stern Hi Alan Stern, even though ed_rm_list is non-NULL, if hc in non-UsbOperation state set SoF status in usbsts register that is illegal, at this time hcd doesn't need care URB whether finished, because hc had into a wrong state. even thoug it doesn't has this patch, URB was not be able to finish when hc in above worng state. except software can intervence this wrong state. but the SoF bit of usbsts register was set by HC, and this action will happen always !!! software clear SoF state I think it isn't make sense. software only disable SoF interrupt to fix HC wrong state. In additon, when kernel include my patch, that it does't happen about what you descriped that driver will not be able to finish unlinging URBs. Because above issue happen in S3/S4(Suspend to disk/Suspend to mem) test procedure, if ed_rm_lis is no-NULL but my patch disable SoF interrupt. then when S3/S4 recovery to cpu idle state that usb resume will be called, reume function has following logic, URB will continue to be processed. static int ohci_rh_resume (struct ohci_hcd *ohci) { ... 242 if (ohci->ed_rm_list) 243 ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrenable); ... } BRS, Yinbo Zhu.
On Sat, Oct 09, 2021 at 10:01:25AM +0800, zhuyinbo wrote: > > 在 2021/10/8 下午10:26, Alan Stern 写道: > > On Fri, Oct 08, 2021 at 03:26:10PM +0800, Yinbo Zhu wrote: > > > The usb states of ohci controller include UsbOperational, UsbReset, > > > UsbSuspend and UsbResume. Among them, only the UsbOperational state > > > supports launching the start of frame for host controller according > > > the ohci protocol spec, but in S3/S4 press test procedure, it may > > Nobody reading this will know what "S3/S4 press test procedure" means. > > You have to explain it, or use a different name that people will > > understand. > okay, I got it. > > > happen that the start of frame was launched in other usb states and > > > cause ohci works abnormally then kernel will allways report rcu > > > call trace. This patch was to add check for host controller > > > functional states and if it is not UsbOperational state that need > > > set INTR_SF in intrdisable register to ensure SOF Token generation > > > was been disabled. > > This doesn't make sense. You already mentioned that only the > > UsbOperational state supports sending start-of-frame packets. So if the > > controller is in a different state then it won't send these packets, > > whether INTR_SF is enabled or not. > > > > What problem are you really trying to solve? > > Only UsbOperational state supports sending start-of-frame packets, but in > fact, in S3/S4 press test procedure, > > usb in non-UsbOperational state that send start-of-frame packets but hc > driver doesn't deal with this frame. and hc will > > allways lauched the SOF for finishing the frame, the cpu will hand this sof > interrupt and doesn't deal with time interrupt > > that will cause rcu call trace then system doesn't suspend to memory/disk. I still don't understand. Are you saying that your OHCI controller behaves badly because it sends SOF packets even when the state is different from UsbOperational? > Hi Alan Stern, > > even though ed_rm_list is non-NULL, if hc in non-UsbOperation state set > SoF status in usbsts register that is illegal, > > at this time hcd doesn't need care URB whether finished, because hc had > into a wrong state. even thoug it doesn't has this patch, > > URB was not be able to finish when hc in above worng state. except software > can intervence this wrong state. but the SoF bit of usbsts > > register was set by HC, and this action will happen always !!! software > clear SoF state I think it isn't make sense. software only disable SoF > > interrupt to fix HC wrong state. This problem happens when you go into S3 or S4 suspend, right? So you should fix the problem by disabling INTR_SF when the root hub is suspended. Try adding /* All ED unlinks should be finished, no need for SOF interrupts */ ohci_writel(ohci, OHCI_INTR_SF, &ohci->regs->intrdisable); into ohci_rh_suspend(), just before the update_done_list() call. If you add this then INTR_SF will not be enabled during S3 or S4 suspend, so the problem shouldn't occur. Does that work for you? > In additon, when kernel include my patch, that it does't happen about > what you descriped that driver will not be able to finish unlinging URBs. > > Because above issue happen in S3/S4(Suspend to disk/Suspend to mem) test > procedure, if ed_rm_lis is no-NULL but my patch disable SoF interrupt. > > then when S3/S4 recovery to cpu idle state that usb resume will be called, > reume function has following logic, URB will continue to be processed. > > static int ohci_rh_resume (struct ohci_hcd *ohci) > > { > > ... > > 242 if (ohci->ed_rm_list) > 243 ohci_writel (ohci, OHCI_INTR_SF, > &ohci->regs->intrenable); > > ... > > } I'm worried that your patch may disable INTR_SF even when the controller has not gone into S3 or S4 suspend. Maybe this won't cause problems, but it's better to be safe and do the disable _only_ when a suspend occurs. Alan Stern
在 2021/10/10 上午3:39, Alan Stern 写道: > On Sat, Oct 09, 2021 at 10:01:25AM +0800, zhuyinbo wrote: >> 在 2021/10/8 下午10:26, Alan Stern 写道: >>> On Fri, Oct 08, 2021 at 03:26:10PM +0800, Yinbo Zhu wrote: >>>> The usb states of ohci controller include UsbOperational, UsbReset, >>>> UsbSuspend and UsbResume. Among them, only the UsbOperational state >>>> supports launching the start of frame for host controller according >>>> the ohci protocol spec, but in S3/S4 press test procedure, it may >>> Nobody reading this will know what "S3/S4 press test procedure" means. >>> You have to explain it, or use a different name that people will >>> understand. >> okay, I got it. >>>> happen that the start of frame was launched in other usb states and >>>> cause ohci works abnormally then kernel will allways report rcu >>>> call trace. This patch was to add check for host controller >>>> functional states and if it is not UsbOperational state that need >>>> set INTR_SF in intrdisable register to ensure SOF Token generation >>>> was been disabled. >>> This doesn't make sense. You already mentioned that only the >>> UsbOperational state supports sending start-of-frame packets. So if the >>> controller is in a different state then it won't send these packets, >>> whether INTR_SF is enabled or not. >>> >>> What problem are you really trying to solve? >> Only UsbOperational state supports sending start-of-frame packets, but in >> fact, in S3/S4 press test procedure, >> >> usb in non-UsbOperational state that send start-of-frame packets but hc >> driver doesn't deal with this frame. and hc will >> >> allways lauched the SOF for finishing the frame, the cpu will hand this sof >> interrupt and doesn't deal with time interrupt >> >> that will cause rcu call trace then system doesn't suspend to memory/disk. > I still don't understand. > > Are you saying that your OHCI controller behaves badly because it sends > SOF packets even when the state is different from UsbOperational? HC will allways report the SoF interrupt in the all time when HC was not in NO-UsbOperation state. and no WritebackDoneHead interrupt that is the issue phenomenon. and this situation is badly state for ohci. > >> Hi Alan Stern, >> >> even though ed_rm_list is non-NULL, if hc in non-UsbOperation state set >> SoF status in usbsts register that is illegal, >> >> at this time hcd doesn't need care URB whether finished, because hc had >> into a wrong state. even thoug it doesn't has this patch, >> >> URB was not be able to finish when hc in above worng state. except software >> can intervence this wrong state. but the SoF bit of usbsts >> >> register was set by HC, and this action will happen always !!! software >> clear SoF state I think it isn't make sense. software only disable SoF >> >> interrupt to fix HC wrong state. > This problem happens when you go into S3 or S4 suspend, right? So you > should fix the problem by disabling INTR_SF when the root hub is > suspended. Try adding > > /* All ED unlinks should be finished, no need for SOF interrupts */ > ohci_writel(ohci, OHCI_INTR_SF, &ohci->regs->intrdisable); > > into ohci_rh_suspend(), just before the update_done_list() call. If you > add this then INTR_SF will not be enabled during S3 or S4 suspend, so > the problem shouldn't occur. Does that work for you? The system doesn't suspend to disk completely by my test result and hc will always produce SoF interrupt. I encountered SoF interrupt issue when HC in UsbSuspend state. and I think when hc in UsbResume/UsbRest/ SoF interrupt issue may be happen so I disable INTR_SF in ohci_irq. So I think disable INTR_SF in suspend function which this way isn't good for me. In addition, I hope my patch was not only fix the bug i encountered and it can limit HC into badly state and it should be the base limit condition and prevent more unknown problems. In fact, HC doesn't deal with ed/td list and done list by the ohci spec, so I think my patch has no risk for ohci. by the way, root hub state isn't completely same with HC, but the root hub reset and resume signaling are controlled by the hcfs bits. and hcd can set hcfs to decide hc usb state, so I judge whether set SF_INT to interrupt disable register only depend on HC state. > >> In additon, when kernel include my patch, that it does't happen about >> what you descriped that driver will not be able to finish unlinging URBs. >> >> Because above issue happen in S3/S4(Suspend to disk/Suspend to mem) test >> procedure, if ed_rm_lis is no-NULL but my patch disable SoF interrupt. >> >> then when S3/S4 recovery to cpu idle state that usb resume will be called, >> reume function has following logic, URB will continue to be processed. >> >> static int ohci_rh_resume (struct ohci_hcd *ohci) >> >> { >> >> ... >> >> 242 if (ohci->ed_rm_list) >> 243 ohci_writel (ohci, OHCI_INTR_SF, >> &ohci->regs->intrenable); >> >> ... >> >> } > I'm worried that your patch may disable INTR_SF even when the controller > has not gone into S3 or S4 suspend. Maybe this won't cause problems, > but it's better to be safe and do the disable _only_ when a suspend > occurs. > > Alan Stern Hi Alan Stern, According to the previous statement, I think my patch has no risk on ohci.
在 2021/10/11 下午1:10, zhuyinbo 写道: > > 在 2021/10/10 上午3:39, Alan Stern 写道: >> On Sat, Oct 09, 2021 at 10:01:25AM +0800, zhuyinbo wrote: >>> 在 2021/10/8 下午10:26, Alan Stern 写道: >>>> On Fri, Oct 08, 2021 at 03:26:10PM +0800, Yinbo Zhu wrote: >>>>> The usb states of ohci controller include UsbOperational, UsbReset, >>>>> UsbSuspend and UsbResume. Among them, only the UsbOperational state >>>>> supports launching the start of frame for host controller according >>>>> the ohci protocol spec, but in S3/S4 press test procedure, it may >>>> Nobody reading this will know what "S3/S4 press test procedure" means. >>>> You have to explain it, or use a different name that people will >>>> understand. >>> okay, I got it. >>>>> happen that the start of frame was launched in other usb states and >>>>> cause ohci works abnormally then kernel will allways report rcu >>>>> call trace. This patch was to add check for host controller >>>>> functional states and if it is not UsbOperational state that need >>>>> set INTR_SF in intrdisable register to ensure SOF Token generation >>>>> was been disabled. >>>> This doesn't make sense. You already mentioned that only the >>>> UsbOperational state supports sending start-of-frame packets. So >>>> if the >>>> controller is in a different state then it won't send these packets, >>>> whether INTR_SF is enabled or not. >>>> >>>> What problem are you really trying to solve? >>> Only UsbOperational state supports sending start-of-frame packets, >>> but in >>> fact, in S3/S4 press test procedure, >>> >>> usb in non-UsbOperational state that send start-of-frame packets but hc >>> driver doesn't deal with this frame. and hc will >>> >>> allways lauched the SOF for finishing the frame, the cpu will hand >>> this sof >>> interrupt and doesn't deal with time interrupt >>> >>> that will cause rcu call trace then system doesn't suspend to >>> memory/disk. >> I still don't understand. >> >> Are you saying that your OHCI controller behaves badly because it sends >> SOF packets even when the state is different from UsbOperational? > > HC will allways report the SoF interrupt in the all time when HC was > not in NO-UsbOperation state. > > and no WritebackDoneHead interrupt that is the issue phenomenon. and > this situation is badly state for ohci. > >> >>> Hi Alan Stern, >>> >>> even though ed_rm_list is non-NULL, if hc in non-UsbOperation >>> state set >>> SoF status in usbsts register that is illegal, >>> >>> at this time hcd doesn't need care URB whether finished, because hc had >>> into a wrong state. even thoug it doesn't has this patch, >>> >>> URB was not be able to finish when hc in above worng state. except >>> software >>> can intervence this wrong state. but the SoF bit of usbsts >>> >>> register was set by HC, and this action will happen always !!! software >>> clear SoF state I think it isn't make sense. software only disable SoF >>> >>> interrupt to fix HC wrong state. >> This problem happens when you go into S3 or S4 suspend, right? So you >> should fix the problem by disabling INTR_SF when the root hub is >> suspended. Try adding >> >> /* All ED unlinks should be finished, no need for SOF interrupts */ >> ohci_writel(ohci, OHCI_INTR_SF, &ohci->regs->intrdisable); >> >> into ohci_rh_suspend(), just before the update_done_list() call. If you >> add this then INTR_SF will not be enabled during S3 or S4 suspend, so >> the problem shouldn't occur. Does that work for you? > > The system doesn't suspend to disk completely by my test result and hc > will always produce SoF interrupt. > > I encountered SoF interrupt issue when HC in UsbSuspend state. and I > think when hc in > > UsbResume/UsbRest/ SoF interrupt issue may be happen so I disable > INTR_SF in ohci_irq. > > So I think disable INTR_SF in suspend function which this way isn't > good for me. > > In addition, I hope my patch was not only fix the bug i > encountered and it can limit HC into badly state and it should be the > > base limit condition and prevent more unknown problems. In fact, HC > doesn't deal with ed/td list and done list by the ohci spec, so > > I think my patch has no risk for ohci. > > by the way, root hub state isn't completely same with HC, but > the root hub reset and resume signaling are controlled by the hcfs bits. > > and hcd can set hcfs to decide hc usb state, so I judge whether set > SF_INT to interrupt disable register only depend on HC state. And I have a test, ohci_rh_suspend was called that HC state as gerneral was also UsbOperational state whatever do s3/s4 test or power on to boot kernel. but HCD record it as suspend state on root hub at this time. > >> >>> In additon, when kernel include my patch, that it does't >>> happen about >>> what you descriped that driver will not be able to finish unlinging >>> URBs. >>> >>> Because above issue happen in S3/S4(Suspend to disk/Suspend to mem) >>> test >>> procedure, if ed_rm_lis is no-NULL but my patch disable SoF interrupt. >>> >>> then when S3/S4 recovery to cpu idle state that usb resume will be >>> called, >>> reume function has following logic, URB will continue to be processed. >>> >>> static int ohci_rh_resume (struct ohci_hcd *ohci) >>> >>> { >>> >>> ... >>> >>> 242 if (ohci->ed_rm_list) >>> 243 ohci_writel (ohci, OHCI_INTR_SF, >>> &ohci->regs->intrenable); >>> >>> ... >>> >>> } >> I'm worried that your patch may disable INTR_SF even when the controller >> has not gone into S3 or S4 suspend. Maybe this won't cause problems, >> but it's better to be safe and do the disable _only_ when a suspend >> occurs. >> >> Alan Stern > > Hi Alan Stern, > > According to the previous statement, I think my patch has no risk > on ohci. > > > >
On Mon, Oct 11, 2021 at 01:10:18PM +0800, zhuyinbo wrote: > > 在 2021/10/10 上午3:39, Alan Stern 写道: > > On Sat, Oct 09, 2021 at 10:01:25AM +0800, zhuyinbo wrote: > > > 在 2021/10/8 下午10:26, Alan Stern 写道: > > > > On Fri, Oct 08, 2021 at 03:26:10PM +0800, Yinbo Zhu wrote: > > > > > The usb states of ohci controller include UsbOperational, UsbReset, > > > > > UsbSuspend and UsbResume. Among them, only the UsbOperational state > > > > > supports launching the start of frame for host controller according > > > > > the ohci protocol spec, but in S3/S4 press test procedure, it may > > > > Nobody reading this will know what "S3/S4 press test procedure" means. > > > > You have to explain it, or use a different name that people will > > > > understand. > > > okay, I got it. > > > > > happen that the start of frame was launched in other usb states and > > > > > cause ohci works abnormally then kernel will allways report rcu > > > > > call trace. This patch was to add check for host controller > > > > > functional states and if it is not UsbOperational state that need > > > > > set INTR_SF in intrdisable register to ensure SOF Token generation > > > > > was been disabled. > > > > This doesn't make sense. You already mentioned that only the > > > > UsbOperational state supports sending start-of-frame packets. So if the > > > > controller is in a different state then it won't send these packets, > > > > whether INTR_SF is enabled or not. > > > > > > > > What problem are you really trying to solve? > > > Only UsbOperational state supports sending start-of-frame packets, but in > > > fact, in S3/S4 press test procedure, > > > > > > usb in non-UsbOperational state that send start-of-frame packets but hc > > > driver doesn't deal with this frame. and hc will > > > > > > allways lauched the SOF for finishing the frame, the cpu will hand this sof > > > interrupt and doesn't deal with time interrupt > > > > > > that will cause rcu call trace then system doesn't suspend to memory/disk. > > I still don't understand. > > > > Are you saying that your OHCI controller behaves badly because it sends > > SOF packets even when the state is different from UsbOperational? > > HC will allways report the SoF interrupt in the all time when HC was not in > NO-UsbOperation state. How did your host controller get into the non-UsbOperational state? What part of the code is responsible for changing to a different state? It looks like the only place where this could happen is in ohci_rh_suspend(). So if you disable SOF interrupts there, it should fix your problem. > and no WritebackDoneHead interrupt that is the issue phenomenon. and this > situation is badly state for ohci. > > > > > > Hi Alan Stern, > > > > > > even though ed_rm_list is non-NULL, if hc in non-UsbOperation state set > > > SoF status in usbsts register that is illegal, > > > > > > at this time hcd doesn't need care URB whether finished, because hc had > > > into a wrong state. even thoug it doesn't has this patch, > > > > > > URB was not be able to finish when hc in above worng state. except software > > > can intervence this wrong state. but the SoF bit of usbsts > > > > > > register was set by HC, and this action will happen always !!! software > > > clear SoF state I think it isn't make sense. software only disable SoF > > > > > > interrupt to fix HC wrong state. > > This problem happens when you go into S3 or S4 suspend, right? So you > > should fix the problem by disabling INTR_SF when the root hub is > > suspended. Try adding > > > > /* All ED unlinks should be finished, no need for SOF interrupts */ > > ohci_writel(ohci, OHCI_INTR_SF, &ohci->regs->intrdisable); > > > > into ohci_rh_suspend(), just before the update_done_list() call. If you > > add this then INTR_SF will not be enabled during S3 or S4 suspend, so > > the problem shouldn't occur. Does that work for you? > > The system doesn't suspend to disk completely by my test result and hc will > always produce SoF interrupt. Have you tried adding those two lines of code shown above? If you haven't tested them, please don't write back until you have. Alan Stern
在 2021/10/12 上午12:17, Alan Stern 写道: > On Mon, Oct 11, 2021 at 01:10:18PM +0800, zhuyinbo wrote: >> 在 2021/10/10 上午3:39, Alan Stern 写道: >>> On Sat, Oct 09, 2021 at 10:01:25AM +0800, zhuyinbo wrote: >>>> 在 2021/10/8 下午10:26, Alan Stern 写道: >>>>> On Fri, Oct 08, 2021 at 03:26:10PM +0800, Yinbo Zhu wrote: >>>>>> The usb states of ohci controller include UsbOperational, UsbReset, >>>>>> UsbSuspend and UsbResume. Among them, only the UsbOperational state >>>>>> supports launching the start of frame for host controller according >>>>>> the ohci protocol spec, but in S3/S4 press test procedure, it may >>>>> Nobody reading this will know what "S3/S4 press test procedure" means. >>>>> You have to explain it, or use a different name that people will >>>>> understand. >>>> okay, I got it. >>>>>> happen that the start of frame was launched in other usb states and >>>>>> cause ohci works abnormally then kernel will allways report rcu >>>>>> call trace. This patch was to add check for host controller >>>>>> functional states and if it is not UsbOperational state that need >>>>>> set INTR_SF in intrdisable register to ensure SOF Token generation >>>>>> was been disabled. >>>>> This doesn't make sense. You already mentioned that only the >>>>> UsbOperational state supports sending start-of-frame packets. So if the >>>>> controller is in a different state then it won't send these packets, >>>>> whether INTR_SF is enabled or not. >>>>> >>>>> What problem are you really trying to solve? >>>> Only UsbOperational state supports sending start-of-frame packets, but in >>>> fact, in S3/S4 press test procedure, >>>> >>>> usb in non-UsbOperational state that send start-of-frame packets but hc >>>> driver doesn't deal with this frame. and hc will >>>> >>>> allways lauched the SOF for finishing the frame, the cpu will hand this sof >>>> interrupt and doesn't deal with time interrupt >>>> >>>> that will cause rcu call trace then system doesn't suspend to memory/disk. >>> I still don't understand. >>> >>> Are you saying that your OHCI controller behaves badly because it sends >>> SOF packets even when the state is different from UsbOperational? >> HC will allways report the SoF interrupt in the all time when HC was not in >> NO-UsbOperation state. > How did your host controller get into the non-UsbOperational state? > What part of the code is responsible for changing to a different state? > > It looks like the only place where this could happen is in > ohci_rh_suspend(). So if you disable SOF interrupts there, it should > fix your problem. in fact, I want to consider all non-UsbOperational state for my patch, as for UsbSuspend state and my issue that your advice is the pefect solution, and apply for the change according to your advice, it can fix my problem by my test. in addition, I got the non-UsbOperationnal state was by read hcfs bits in ohci control register, for the UsbSuspend status that it is only changed in ohci_rh_suspend. and other states was changed in multiple place that seems disable sof interrupt was only in ohci_irq. but if you still think it has risk i want to following your advice and as it v5 version. > >> and no WritebackDoneHead interrupt that is the issue phenomenon. and this >> situation is badly state for ohci. >> >>>> Hi Alan Stern, >>>> >>>> even though ed_rm_list is non-NULL, if hc in non-UsbOperation state set >>>> SoF status in usbsts register that is illegal, >>>> >>>> at this time hcd doesn't need care URB whether finished, because hc had >>>> into a wrong state. even thoug it doesn't has this patch, >>>> >>>> URB was not be able to finish when hc in above worng state. except software >>>> can intervence this wrong state. but the SoF bit of usbsts >>>> >>>> register was set by HC, and this action will happen always !!! software >>>> clear SoF state I think it isn't make sense. software only disable SoF >>>> >>>> interrupt to fix HC wrong state. >>> This problem happens when you go into S3 or S4 suspend, right? So you >>> should fix the problem by disabling INTR_SF when the root hub is >>> suspended. Try adding >>> >>> /* All ED unlinks should be finished, no need for SOF interrupts */ >>> ohci_writel(ohci, OHCI_INTR_SF, &ohci->regs->intrdisable); >>> >>> into ohci_rh_suspend(), just before the update_done_list() call. If you >>> add this then INTR_SF will not be enabled during S3 or S4 suspend, so >>> the problem shouldn't occur. Does that work for you? >> The system doesn't suspend to disk completely by my test result and hc will >> always produce SoF interrupt. > Have you tried adding those two lines of code shown above? > > If you haven't tested them, please don't write back until you have. > > Alan Stern Hi Alan stern, I have a try that follow your advice and the s3/s4 test result is good for me. Thanks, Yinbo Zhu.
diff --git a/drivers/usb/host/ohci-hcd.c b/drivers/usb/host/ohci-hcd.c index 1f5e693..87aa9bb 100644 --- a/drivers/usb/host/ohci-hcd.c +++ b/drivers/usb/host/ohci-hcd.c @@ -879,7 +879,8 @@ static irqreturn_t ohci_irq (struct usb_hcd *hcd) { struct ohci_hcd *ohci = hcd_to_ohci (hcd); struct ohci_regs __iomem *regs = ohci->regs; - int ints; + int ints, ctl; + /* Read interrupt status (and flush pending writes). We ignore the * optimization of checking the LSB of hcca->done_head; it doesn't @@ -969,9 +970,15 @@ static irqreturn_t ohci_irq (struct usb_hcd *hcd) * when there's still unlinking to be done (next frame). */ ohci_work(ohci); - if ((ints & OHCI_INTR_SF) != 0 && !ohci->ed_rm_list - && ohci->rh_state == OHCI_RH_RUNNING) + + ctl = ohci_readl(ohci, ®s->control); + + if (((ints & OHCI_INTR_SF) != 0 && !ohci->ed_rm_list + && ohci->rh_state == OHCI_RH_RUNNING) || + ((ctl & OHCI_CTRL_HCFS) != OHCI_USB_OPER)) { ohci_writel (ohci, OHCI_INTR_SF, ®s->intrdisable); + (void)ohci_readl(ohci, ®s->intrdisable); + } if (ohci->rh_state == OHCI_RH_RUNNING) { ohci_writel (ohci, ints, ®s->intrstatus);
The usb states of ohci controller include UsbOperational, UsbReset, UsbSuspend and UsbResume. Among them, only the UsbOperational state supports launching the start of frame for host controller according the ohci protocol spec, but in S3/S4 press test procedure, it may happen that the start of frame was launched in other usb states and cause ohci works abnormally then kernel will allways report rcu call trace. This patch was to add check for host controller functional states and if it is not UsbOperational state that need set INTR_SF in intrdisable register to ensure SOF Token generation was been disabled. Signed-off-by: Yinbo Zhu <zhuyinbo@loongson.cn> --- Change in v3: Rework the commit information. Move the patch code change to lower down position in ohci_irq. drivers/usb/host/ohci-hcd.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-)