| Message ID | 20211201025419.2797624-2-helgaas@kernel.org (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
| Series | agp: convert to generic power management | expand |
[cc->to: Rafael: help :)] On Tue, Nov 30, 2021 at 08:54:17PM -0600, Bjorn Helgaas wrote: > From: Vaibhav Gupta <vaibhavgupta40@gmail.com> > > Convert amd64-agp from legacy PCI power management to the generic power > management framework. > > Previously, amd64-agp used legacy PCI power management. > agp_amd64_suspend() looked like this: > > agp_amd64_suspend > pci_save_state(pdev) > pci_set_power_state(pdev, pci_choose_state(pdev, state)) > > With generic power management, these are both done by the PCI core in > pci_pm_runtime_suspend(), so drop agp_amd64_suspend() completely. I think the *patch* is correct, but my explanation is wrong. Would appreciate any corrections! Prior to this patch, agp_amd64_suspend() is a pci_driver.suspend() method and is called in this path: pci_pm_suspend pci_legacy_suspend drv->suspend After this patch, agp_amd64_suspend() is not implemented at all, and we do the pci_save_state() and pci_set_power_state() in PCI generic code. But I think those actually happen in pci_pm_suspend_noirq(), not in pci_pm_runtime_suspend(), i.e., in this path: suspend_devices_and_enter dpm_suspend_start(PMSG_SUSPEND) dpm_suspend(PMSG_SUSPEND) device_suspend __device_suspend callback = pm_op(dev->bus->pm, state) dpm_run_callback(callback) pci_pm_suspend # PCI bus method dev->driver->pm->suspend agp_amd64_suspend # <-- no longer needed suspend_enter dpm_suspend_noirq(PMSG_SUSPEND) dpm_noirq_suspend_devices(PMSG_SUSPEND) device_suspend_noirq __device_suspend_noirq callback = pm_noirq_op(dev->bus->pm, state) dpm_run_callback(callback) pci_pm_suspend_noirq # PCI bus method pci_save_state # <-- now done here pci_prepare_to_sleep pci_set_power_state # <-- and here I got confused because I couldn't find the call chain leading to pci_pm_suspend_noirq(). pm_op() and dpm_run_callback() essentially break the call chain, which makes it a little hard to follow. > agp_amd64_resume() looked like this: > > agp_amd64_resume > pci_set_power_state(pdev, PCI_D0) > pci_restore_state(pdev) > ... > > With generic power management, the PCI parts are done by > pci_pm_runtime_resume(), so drop those from agp_amd64_resume(). > > [bhelgaas: commit log] > Signed-off-by: Vaibhav Gupta <vaibhavgupta40@gmail.com> > Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> > --- > drivers/char/agp/amd64-agp.c | 24 ++++++------------------ > 1 file changed, 6 insertions(+), 18 deletions(-) > > diff --git a/drivers/char/agp/amd64-agp.c b/drivers/char/agp/amd64-agp.c > index b40edae32817..dc78a4fb879e 100644 > --- a/drivers/char/agp/amd64-agp.c > +++ b/drivers/char/agp/amd64-agp.c > @@ -588,20 +588,11 @@ static void agp_amd64_remove(struct pci_dev *pdev) > agp_bridges_found--; > } > > -#ifdef CONFIG_PM > +#define agp_amd64_suspend NULL > > -static int agp_amd64_suspend(struct pci_dev *pdev, pm_message_t state) > +static int __maybe_unused agp_amd64_resume(struct device *dev) > { > - pci_save_state(pdev); > - pci_set_power_state(pdev, pci_choose_state(pdev, state)); > - > - return 0; > -} > - > -static int agp_amd64_resume(struct pci_dev *pdev) > -{ > - pci_set_power_state(pdev, PCI_D0); > - pci_restore_state(pdev); > + struct pci_dev *pdev = to_pci_dev(dev); > > if (pdev->vendor == PCI_VENDOR_ID_NVIDIA) > nforce3_agp_init(pdev); > @@ -609,8 +600,6 @@ static int agp_amd64_resume(struct pci_dev *pdev) > return amd_8151_configure(); > } > > -#endif /* CONFIG_PM */ > - > static const struct pci_device_id agp_amd64_pci_table[] = { > { > .class = (PCI_CLASS_BRIDGE_HOST << 8), > @@ -738,15 +727,14 @@ static const struct pci_device_id agp_amd64_pci_promisc_table[] = { > { } > }; > > +static SIMPLE_DEV_PM_OPS(agp_amd64_pm_ops, agp_amd64_suspend, agp_amd64_resume); > + > static struct pci_driver agp_amd64_pci_driver = { > .name = "agpgart-amd64", > .id_table = agp_amd64_pci_table, > .probe = agp_amd64_probe, > .remove = agp_amd64_remove, > -#ifdef CONFIG_PM > - .suspend = agp_amd64_suspend, > - .resume = agp_amd64_resume, > -#endif > + .driver.pm = &agp_amd64_pm_ops, > }; > > > -- > 2.25.1 >
diff --git a/drivers/char/agp/amd64-agp.c b/drivers/char/agp/amd64-agp.c index b40edae32817..dc78a4fb879e 100644 --- a/drivers/char/agp/amd64-agp.c +++ b/drivers/char/agp/amd64-agp.c @@ -588,20 +588,11 @@ static void agp_amd64_remove(struct pci_dev *pdev) agp_bridges_found--; } -#ifdef CONFIG_PM +#define agp_amd64_suspend NULL -static int agp_amd64_suspend(struct pci_dev *pdev, pm_message_t state) +static int __maybe_unused agp_amd64_resume(struct device *dev) { - pci_save_state(pdev); - pci_set_power_state(pdev, pci_choose_state(pdev, state)); - - return 0; -} - -static int agp_amd64_resume(struct pci_dev *pdev) -{ - pci_set_power_state(pdev, PCI_D0); - pci_restore_state(pdev); + struct pci_dev *pdev = to_pci_dev(dev); if (pdev->vendor == PCI_VENDOR_ID_NVIDIA) nforce3_agp_init(pdev); @@ -609,8 +600,6 @@ static int agp_amd64_resume(struct pci_dev *pdev) return amd_8151_configure(); } -#endif /* CONFIG_PM */ - static const struct pci_device_id agp_amd64_pci_table[] = { { .class = (PCI_CLASS_BRIDGE_HOST << 8), @@ -738,15 +727,14 @@ static const struct pci_device_id agp_amd64_pci_promisc_table[] = { { } }; +static SIMPLE_DEV_PM_OPS(agp_amd64_pm_ops, agp_amd64_suspend, agp_amd64_resume); + static struct pci_driver agp_amd64_pci_driver = { .name = "agpgart-amd64", .id_table = agp_amd64_pci_table, .probe = agp_amd64_probe, .remove = agp_amd64_remove, -#ifdef CONFIG_PM - .suspend = agp_amd64_suspend, - .resume = agp_amd64_resume, -#endif + .driver.pm = &agp_amd64_pm_ops, };