| Message ID | 1609231431-10048-7-git-send-email-loic.poulain@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | mhi: pci_generic: Misc improvements | expand |
On Tue, Dec 29, 2020 at 09:43:47AM +0100, Loic Poulain wrote: > Add support for system wide suspend/resume. During suspend, MHI > device controller must be put in M3 state and PCI bus in D3 state. > > Add a recovery procedure allowing to reinitialize the device in case > of error during resume steps, which can happen if device loses power > (and so its context) while system suspend. > > Signed-off-by: Loic Poulain <loic.poulain@linaro.org> > Reviewed-by Hemant Kumar <hemantk@codeaurora.org> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Thanks, Mani > --- > drivers/bus/mhi/pci_generic.c | 105 ++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 105 insertions(+) > > diff --git a/drivers/bus/mhi/pci_generic.c b/drivers/bus/mhi/pci_generic.c > index 2521cd4..3297d95 100644 > --- a/drivers/bus/mhi/pci_generic.c > +++ b/drivers/bus/mhi/pci_generic.c > @@ -13,6 +13,7 @@ > #include <linux/mhi.h> > #include <linux/module.h> > #include <linux/pci.h> > +#include <linux/workqueue.h> > > #define MHI_PCI_DEFAULT_BAR_NUM 0 > > @@ -186,6 +187,7 @@ enum mhi_pci_device_status { > struct mhi_pci_device { > struct mhi_controller mhi_cntrl; > struct pci_saved_state *pci_state; > + struct work_struct recovery_work; > unsigned long status; > }; > > @@ -313,6 +315,50 @@ static void mhi_pci_runtime_put(struct mhi_controller *mhi_cntrl) > /* no PM for now */ > } > > +static void mhi_pci_recovery_work(struct work_struct *work) > +{ > + struct mhi_pci_device *mhi_pdev = container_of(work, struct mhi_pci_device, > + recovery_work); > + struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl; > + struct pci_dev *pdev = to_pci_dev(mhi_cntrl->cntrl_dev); > + int err; > + > + dev_warn(&pdev->dev, "device recovery started\n"); > + > + /* Clean up MHI state */ > + if (test_and_clear_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status)) { > + mhi_power_down(mhi_cntrl, false); > + mhi_unprepare_after_power_down(mhi_cntrl); > + } > + > + /* Check if we can recover without full reset */ > + pci_set_power_state(pdev, PCI_D0); > + pci_load_saved_state(pdev, mhi_pdev->pci_state); > + pci_restore_state(pdev); > + > + if (!mhi_pci_is_alive(mhi_cntrl)) > + goto err_try_reset; > + > + err = mhi_prepare_for_power_up(mhi_cntrl); > + if (err) > + goto err_try_reset; > + > + err = mhi_sync_power_up(mhi_cntrl); > + if (err) > + goto err_unprepare; > + > + dev_dbg(&pdev->dev, "Recovery completed\n"); > + > + set_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status); > + return; > + > +err_unprepare: > + mhi_unprepare_after_power_down(mhi_cntrl); > +err_try_reset: > + if (pci_reset_function(pdev)) > + dev_err(&pdev->dev, "Recovery failed\n"); > +} > + > static int mhi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) > { > const struct mhi_pci_dev_info *info = (struct mhi_pci_dev_info *) id->driver_data; > @@ -327,6 +373,8 @@ static int mhi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) > if (!mhi_pdev) > return -ENOMEM; > > + INIT_WORK(&mhi_pdev->recovery_work, mhi_pci_recovery_work); > + > mhi_cntrl_config = info->config; > mhi_cntrl = &mhi_pdev->mhi_cntrl; > > @@ -391,6 +439,8 @@ static void mhi_pci_remove(struct pci_dev *pdev) > struct mhi_pci_device *mhi_pdev = pci_get_drvdata(pdev); > struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl; > > + cancel_work_sync(&mhi_pdev->recovery_work); > + > if (test_and_clear_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status)) { > mhi_power_down(mhi_cntrl, true); > mhi_unprepare_after_power_down(mhi_cntrl); > @@ -456,12 +506,67 @@ static const struct pci_error_handlers mhi_pci_err_handler = { > .reset_done = mhi_pci_reset_done, > }; > > +static int __maybe_unused mhi_pci_suspend(struct device *dev) > +{ > + struct pci_dev *pdev = to_pci_dev(dev); > + struct mhi_pci_device *mhi_pdev = dev_get_drvdata(dev); > + struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl; > + > + cancel_work_sync(&mhi_pdev->recovery_work); > + > + /* Transition to M3 state */ > + mhi_pm_suspend(mhi_cntrl); > + > + pci_save_state(pdev); > + pci_disable_device(pdev); > + pci_wake_from_d3(pdev, true); > + pci_set_power_state(pdev, PCI_D3hot); > + > + return 0; > +} > + > +static int __maybe_unused mhi_pci_resume(struct device *dev) > +{ > + struct pci_dev *pdev = to_pci_dev(dev); > + struct mhi_pci_device *mhi_pdev = dev_get_drvdata(dev); > + struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl; > + int err; > + > + pci_set_power_state(pdev, PCI_D0); > + pci_restore_state(pdev); > + pci_set_master(pdev); > + > + err = pci_enable_device(pdev); > + if (err) > + goto err_recovery; > + > + /* Exit M3, transition to M0 state */ > + err = mhi_pm_resume(mhi_cntrl); > + if (err) { > + dev_err(&pdev->dev, "failed to resume device: %d\n", err); > + goto err_recovery; > + } > + > + return 0; > + > +err_recovery: > + /* The device may have loose power or crashed, try recovering it */ > + queue_work(system_long_wq, &mhi_pdev->recovery_work); > + > + return err; > +} > + > +static const struct dev_pm_ops mhi_pci_pm_ops = { > + SET_SYSTEM_SLEEP_PM_OPS(mhi_pci_suspend, mhi_pci_resume) > +}; > + > static struct pci_driver mhi_pci_driver = { > .name = "mhi-pci-generic", > .id_table = mhi_pci_id_table, > .probe = mhi_pci_probe, > .remove = mhi_pci_remove, > .err_handler = &mhi_pci_err_handler, > + .driver.pm = &mhi_pci_pm_ops > }; > module_pci_driver(mhi_pci_driver); > > -- > 2.7.4 >
diff --git a/drivers/bus/mhi/pci_generic.c b/drivers/bus/mhi/pci_generic.c index 2521cd4..3297d95 100644 --- a/drivers/bus/mhi/pci_generic.c +++ b/drivers/bus/mhi/pci_generic.c @@ -13,6 +13,7 @@ #include <linux/mhi.h> #include <linux/module.h> #include <linux/pci.h> +#include <linux/workqueue.h> #define MHI_PCI_DEFAULT_BAR_NUM 0 @@ -186,6 +187,7 @@ enum mhi_pci_device_status { struct mhi_pci_device { struct mhi_controller mhi_cntrl; struct pci_saved_state *pci_state; + struct work_struct recovery_work; unsigned long status; }; @@ -313,6 +315,50 @@ static void mhi_pci_runtime_put(struct mhi_controller *mhi_cntrl) /* no PM for now */ } +static void mhi_pci_recovery_work(struct work_struct *work) +{ + struct mhi_pci_device *mhi_pdev = container_of(work, struct mhi_pci_device, + recovery_work); + struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl; + struct pci_dev *pdev = to_pci_dev(mhi_cntrl->cntrl_dev); + int err; + + dev_warn(&pdev->dev, "device recovery started\n"); + + /* Clean up MHI state */ + if (test_and_clear_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status)) { + mhi_power_down(mhi_cntrl, false); + mhi_unprepare_after_power_down(mhi_cntrl); + } + + /* Check if we can recover without full reset */ + pci_set_power_state(pdev, PCI_D0); + pci_load_saved_state(pdev, mhi_pdev->pci_state); + pci_restore_state(pdev); + + if (!mhi_pci_is_alive(mhi_cntrl)) + goto err_try_reset; + + err = mhi_prepare_for_power_up(mhi_cntrl); + if (err) + goto err_try_reset; + + err = mhi_sync_power_up(mhi_cntrl); + if (err) + goto err_unprepare; + + dev_dbg(&pdev->dev, "Recovery completed\n"); + + set_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status); + return; + +err_unprepare: + mhi_unprepare_after_power_down(mhi_cntrl); +err_try_reset: + if (pci_reset_function(pdev)) + dev_err(&pdev->dev, "Recovery failed\n"); +} + static int mhi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) { const struct mhi_pci_dev_info *info = (struct mhi_pci_dev_info *) id->driver_data; @@ -327,6 +373,8 @@ static int mhi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) if (!mhi_pdev) return -ENOMEM; + INIT_WORK(&mhi_pdev->recovery_work, mhi_pci_recovery_work); + mhi_cntrl_config = info->config; mhi_cntrl = &mhi_pdev->mhi_cntrl; @@ -391,6 +439,8 @@ static void mhi_pci_remove(struct pci_dev *pdev) struct mhi_pci_device *mhi_pdev = pci_get_drvdata(pdev); struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl; + cancel_work_sync(&mhi_pdev->recovery_work); + if (test_and_clear_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status)) { mhi_power_down(mhi_cntrl, true); mhi_unprepare_after_power_down(mhi_cntrl); @@ -456,12 +506,67 @@ static const struct pci_error_handlers mhi_pci_err_handler = { .reset_done = mhi_pci_reset_done, }; +static int __maybe_unused mhi_pci_suspend(struct device *dev) +{ + struct pci_dev *pdev = to_pci_dev(dev); + struct mhi_pci_device *mhi_pdev = dev_get_drvdata(dev); + struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl; + + cancel_work_sync(&mhi_pdev->recovery_work); + + /* Transition to M3 state */ + mhi_pm_suspend(mhi_cntrl); + + pci_save_state(pdev); + pci_disable_device(pdev); + pci_wake_from_d3(pdev, true); + pci_set_power_state(pdev, PCI_D3hot); + + return 0; +} + +static int __maybe_unused mhi_pci_resume(struct device *dev) +{ + struct pci_dev *pdev = to_pci_dev(dev); + struct mhi_pci_device *mhi_pdev = dev_get_drvdata(dev); + struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl; + int err; + + pci_set_power_state(pdev, PCI_D0); + pci_restore_state(pdev); + pci_set_master(pdev); + + err = pci_enable_device(pdev); + if (err) + goto err_recovery; + + /* Exit M3, transition to M0 state */ + err = mhi_pm_resume(mhi_cntrl); + if (err) { + dev_err(&pdev->dev, "failed to resume device: %d\n", err); + goto err_recovery; + } + + return 0; + +err_recovery: + /* The device may have loose power or crashed, try recovering it */ + queue_work(system_long_wq, &mhi_pdev->recovery_work); + + return err; +} + +static const struct dev_pm_ops mhi_pci_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(mhi_pci_suspend, mhi_pci_resume) +}; + static struct pci_driver mhi_pci_driver = { .name = "mhi-pci-generic", .id_table = mhi_pci_id_table, .probe = mhi_pci_probe, .remove = mhi_pci_remove, .err_handler = &mhi_pci_err_handler, + .driver.pm = &mhi_pci_pm_ops }; module_pci_driver(mhi_pci_driver);
Add support for system wide suspend/resume. During suspend, MHI device controller must be put in M3 state and PCI bus in D3 state. Add a recovery procedure allowing to reinitialize the device in case of error during resume steps, which can happen if device loses power (and so its context) while system suspend. Signed-off-by: Loic Poulain <loic.poulain@linaro.org> Reviewed-by Hemant Kumar <hemantk@codeaurora.org> --- drivers/bus/mhi/pci_generic.c | 105 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 105 insertions(+) -- 2.7.4