| Message ID | 20130710160704.GH18966@arwen.pp.htv.fi (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi, On Wed, Jul 10, 2013 at 07:07:04PM +0300, Felipe Balbi wrote: > how about something like below ? It makes omap_device/hwmod and > pm_runtime agree on the initial state of the device and will prevent > ->runtime_resume() from being called on first pm_runtime_get*() done > during probe. > > This is similar to what PCI bus does (if you look at pci_pm_init()). > > commit 59108a500b4ab4b1a5102648a3360276dbf7df6f > Author: Felipe Balbi <balbi@ti.com> > Date: Wed Jul 10 18:50:16 2013 +0300 > > arm: omap2plus: unidle devices which are about to probe > > in order to make HWMOD and pm_runtime agree on the > initial state of the device, we will unidle the device > and call pm_runtime_set_active() to tell pm_runtime > that the device is really active. > > By the time driver's probe() is reached, a call to > pm_runtime_get_sync() will not cause driver's > ->runtime_resume() method to be called at first, only > after a successful ->runtime_suspend(). > > Signed-off-by: Felipe Balbi <balbi@ti.com> btw, this is RFC, haven't tested at all.
* Felipe Balbi <balbi@ti.com> [130710 09:18]: > > On Wed, Jul 10, 2013 at 07:07:04PM +0300, Felipe Balbi wrote: > > how about something like below ? It makes omap_device/hwmod and > > pm_runtime agree on the initial state of the device and will prevent > > ->runtime_resume() from being called on first pm_runtime_get*() done > > during probe. > > > > This is similar to what PCI bus does (if you look at pci_pm_init()). > > > > commit 59108a500b4ab4b1a5102648a3360276dbf7df6f > > Author: Felipe Balbi <balbi@ti.com> > > Date: Wed Jul 10 18:50:16 2013 +0300 > > > > arm: omap2plus: unidle devices which are about to probe > > > > in order to make HWMOD and pm_runtime agree on the > > initial state of the device, we will unidle the device > > and call pm_runtime_set_active() to tell pm_runtime > > that the device is really active. > > > > By the time driver's probe() is reached, a call to > > pm_runtime_get_sync() will not cause driver's > > ->runtime_resume() method to be called at first, only > > after a successful ->runtime_suspend(). > > > > Signed-off-by: Felipe Balbi <balbi@ti.com> > > btw, this is RFC, haven't tested at all. Yes it does not compile, then removing the extra ; at the end of the functions, it oopses with a NULL pointer exception. Regards, Tony -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi, On 07/11/2013 09:32 AM, Tony Lindgren wrote: > * Felipe Balbi <balbi@ti.com> [130710 09:18]: >> >> On Wed, Jul 10, 2013 at 07:07:04PM +0300, Felipe Balbi wrote: >>> how about something like below ? It makes omap_device/hwmod and >>> pm_runtime agree on the initial state of the device and will prevent >>> ->runtime_resume() from being called on first pm_runtime_get*() done >>> during probe. >>> >>> This is similar to what PCI bus does (if you look at pci_pm_init()). >>> >>> commit 59108a500b4ab4b1a5102648a3360276dbf7df6f >>> Author: Felipe Balbi <balbi@ti.com> >>> Date: Wed Jul 10 18:50:16 2013 +0300 >>> >>> arm: omap2plus: unidle devices which are about to probe >>> >>> in order to make HWMOD and pm_runtime agree on the >>> initial state of the device, we will unidle the device >>> and call pm_runtime_set_active() to tell pm_runtime >>> that the device is really active. Don't think that it's good idea ( I've checked some driver's and think this patch will enable some devices unpredictably: - hwspinlock - mailbox - iommu - ipu All above devices need to be enabled on demand only (no pm_runtime_get*() calls in probe). More over, some of them have very specific enabling sequence - like ipu). May be Summan can say more on that. >>> >>> By the time driver's probe() is reached, a call to >>> pm_runtime_get_sync() will not cause driver's >>> ->runtime_resume() method to be called at first, only >>> after a successful ->runtime_suspend(). >>> >>> Signed-off-by: Felipe Balbi <balbi@ti.com> >> >> btw, this is RFC, haven't tested at all. > > Yes it does not compile, then removing the extra ; at the end > of the functions, it oopses with a NULL pointer exception. > > Regards, > > Tony > -- > To unsubscribe from this list: send the line "unsubscribe linux-omap" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 07/11/2013 04:59 AM, Grygorii Strashko wrote: > Hi, > > On 07/11/2013 09:32 AM, Tony Lindgren wrote: >> * Felipe Balbi <balbi@ti.com> [130710 09:18]: >>> >>> On Wed, Jul 10, 2013 at 07:07:04PM +0300, Felipe Balbi wrote: >>>> how about something like below ? It makes omap_device/hwmod and >>>> pm_runtime agree on the initial state of the device and will prevent >>>> ->runtime_resume() from being called on first pm_runtime_get*() done >>>> during probe. >>>> >>>> This is similar to what PCI bus does (if you look at pci_pm_init()). >>>> >>>> commit 59108a500b4ab4b1a5102648a3360276dbf7df6f >>>> Author: Felipe Balbi <balbi@ti.com> >>>> Date: Wed Jul 10 18:50:16 2013 +0300 >>>> >>>> arm: omap2plus: unidle devices which are about to probe >>>> >>>> in order to make HWMOD and pm_runtime agree on the >>>> initial state of the device, we will unidle the device >>>> and call pm_runtime_set_active() to tell pm_runtime >>>> that the device is really active. > Don't think that it's good idea ( > I've checked some driver's and think this patch will enable some devices > unpredictably: > - hwspinlock > - mailbox > - iommu > - ipu > All above devices need to be enabled on demand only (no > pm_runtime_get*() calls in probe). More over, some of them have very > specific enabling sequence - like ipu). > > May be Summan can say more on that. Indeed, this is a problem for any of the slave processor devices. mailbox and iommu would be slaves to the remoteproc and the drivers have a specific sequence of bringing up a processor. The current hwmod/omap_device code is such that these devices will be left in reset and the driver code use the omap_device_(de)assert_hardreset API together with omap_device_enable code to bring up the devices. The remoteproc driver also needs to assert the resets (there are other problems associated with using omap_device_idle for remoteproc and iommu) for bringing up the devices after a suspend sequence. hwspinlock and mailbox may get away since they are in CORE domain, but definitely an issue for iommu and remoteproc. I would think that this would also affect other compute devices like IVAHD, ISS, SGX. regards Suman > >>>> >>>> By the time driver's probe() is reached, a call to >>>> pm_runtime_get_sync() will not cause driver's >>>> ->runtime_resume() method to be called at first, only >>>> after a successful ->runtime_suspend(). >>>> >>>> Signed-off-by: Felipe Balbi <balbi@ti.com> >>> >>> btw, this is RFC, haven't tested at all. >> >> Yes it does not compile, then removing the extra ; at the end >> of the functions, it oopses with a NULL pointer exception. >> >> Regards, >> >> Tony >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-omap" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Friday 12 July 2013 06:10 AM, Suman Anna wrote: > On 07/11/2013 04:59 AM, Grygorii Strashko wrote: >> Hi, >> >> On 07/11/2013 09:32 AM, Tony Lindgren wrote: >>> * Felipe Balbi <balbi@ti.com> [130710 09:18]: >>>> >>>> On Wed, Jul 10, 2013 at 07:07:04PM +0300, Felipe Balbi wrote: >>>>> how about something like below ? It makes omap_device/hwmod and >>>>> pm_runtime agree on the initial state of the device and will prevent >>>>> ->runtime_resume() from being called on first pm_runtime_get*() done >>>>> during probe. >>>>> >>>>> This is similar to what PCI bus does (if you look at pci_pm_init()). >>>>> >>>>> commit 59108a500b4ab4b1a5102648a3360276dbf7df6f >>>>> Author: Felipe Balbi <balbi@ti.com> >>>>> Date: Wed Jul 10 18:50:16 2013 +0300 >>>>> >>>>> arm: omap2plus: unidle devices which are about to probe >>>>> >>>>> in order to make HWMOD and pm_runtime agree on the >>>>> initial state of the device, we will unidle the device >>>>> and call pm_runtime_set_active() to tell pm_runtime >>>>> that the device is really active. >> Don't think that it's good idea ( >> I've checked some driver's and think this patch will enable some devices >> unpredictably: >> - hwspinlock >> - mailbox >> - iommu >> - ipu >> All above devices need to be enabled on demand only (no >> pm_runtime_get*() calls in probe). More over, some of them have very >> specific enabling sequence - like ipu). >> >> May be Summan can say more on that. > > Indeed, this is a problem for any of the slave processor devices. > mailbox and iommu would be slaves to the remoteproc and the drivers have > a specific sequence of bringing up a processor. The current > hwmod/omap_device code is such that these devices will be left in reset > and the driver code use the omap_device_(de)assert_hardreset API > together with omap_device_enable code to bring up the devices. The > remoteproc driver also needs to assert the resets (there are other > problems associated with using omap_device_idle for remoteproc and > iommu) for bringing up the devices after a suspend sequence. hwspinlock > and mailbox may get away since they are in CORE domain, but definitely > an issue for iommu and remoteproc. I would think that this would also > affect other compute devices like IVAHD, ISS, SGX. Today, for these IPs I guess hwmod waits for the resets to be de-asserted, right? /* * If an IP block contains HW reset lines and all of them are * asserted, we let integration code associated with that * block handle the enable. We've received very little * information on what those driver authors need, and until * detailed information is provided and the driver code is * posted to the public lists, this is probably the best we * can do. */ if (_are_all_hardreset_lines_asserted(oh)) return 0; What if this information is send back to omap_device() through a return value so omap_device() knows about this too, so it avoids marking the omap device as enabled? Wouldn't that fix the issue? > > regards > Suman > >> >>>>> >>>>> By the time driver's probe() is reached, a call to >>>>> pm_runtime_get_sync() will not cause driver's >>>>> ->runtime_resume() method to be called at first, only >>>>> after a successful ->runtime_suspend(). >>>>> >>>>> Signed-off-by: Felipe Balbi <balbi@ti.com> >>>> >>>> btw, this is RFC, haven't tested at all. >>> >>> Yes it does not compile, then removing the extra ; at the end >>> of the functions, it oopses with a NULL pointer exception. >>> >>> Regards, >>> >>> Tony >>> -- >>> To unsubscribe from this list: send the line "unsubscribe linux-omap" in >>> the body of a message to majordomo@vger.kernel.org >>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>> >> > -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/arm/mach-omap2/omap_device.c b/arch/arm/mach-omap2/omap_device.c index e6d2307..1cedf3a 100644 --- a/arch/arm/mach-omap2/omap_device.c +++ b/arch/arm/mach-omap2/omap_device.c @@ -181,6 +181,26 @@ odbfd_exit: return ret; } +static void omap_device_pm_init(struct platform_device *pdev); +{ + /* + * if we reach this function, it's because the device is about to be + * probed. In such cases, we will enable the device, and call + * pm_runtime_set_active() so that the device driver and runtime PM + * framework agree on initial state of the device. + */ + omap_device_enable(pdev); + pm_runtime_set_active(&pdev->dev); + device_enable_async_suspend(&pdev->dev); +} + +static void omap_device_pm_exit(struct platform_device *pdev); +{ + device_disable_async_suspend(&pdev->dev); + pm_runtime_set_suspended(&pdev->dev); + omap_device_idle(pdev); +} + static int _omap_device_notifier_call(struct notifier_block *nb, unsigned long event, void *dev) { @@ -192,6 +212,12 @@ static int _omap_device_notifier_call(struct notifier_block *nb, if (pdev->archdata.od) omap_device_delete(pdev->archdata.od); break; + case BUS_NOTIFY_BIND_DRIVER: + omap_device_pm_init(pdev); + break; + case BUS_NOTIFY_UNBOUND_DRIVER: + omap_device_pm_exit(pdev); + break; case BUS_NOTIFY_ADD_DEVICE: if (pdev->dev.of_node) omap_device_build_from_dt(pdev);