| Message ID | 1605279602-18749-5-git-send-email-loic.poulain@linaro.org (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | mhi: pci_generic: Misc improvements | expand |
On 2020-11-13 06:59, Loic Poulain wrote: > Add support for resetting the device, reset can be triggered in case > of error or manually via sysfs (/sys/bus/pci/devices/*/reset). > > Signed-off-by: Loic Poulain <loic.poulain@linaro.org> > --- > drivers/bus/mhi/pci_generic.c | 117 > +++++++++++++++++++++++++++++++++++++----- > 1 file changed, 104 insertions(+), 13 deletions(-) > > diff --git a/drivers/bus/mhi/pci_generic.c > b/drivers/bus/mhi/pci_generic.c > index 0c07cf5..b48c382 100644 > --- a/drivers/bus/mhi/pci_generic.c > +++ b/drivers/bus/mhi/pci_generic.c > @@ -8,6 +8,7 @@ > * Copyright (C) 2020 Linaro Ltd <loic.poulain@linaro.org> > */ > > +#include <linux/delay.h> > #include <linux/device.h> > #include <linux/mhi.h> > #include <linux/module.h> > @@ -179,6 +180,16 @@ static const struct pci_device_id > mhi_pci_id_table[] = { > }; > MODULE_DEVICE_TABLE(pci, mhi_pci_id_table); > > +enum mhi_pci_device_status { > + MHI_PCI_DEV_STARTED, > +}; > + > +struct mhi_pci_device { > + struct mhi_controller mhi_cntrl; > + struct pci_saved_state *pci_state; > + unsigned long status; > +}; > + > static int mhi_pci_read_reg(struct mhi_controller *mhi_cntrl, > void __iomem *addr, u32 *out) > { > @@ -203,6 +214,20 @@ static inline void mhi_pci_reset(struct > mhi_controller *mhi_cntrl) > writel(1, mhi_cntrl->regs + DEV_RESET_REG); > } > > +static bool mhi_pci_is_alive(struct mhi_controller *mhi_cntrl) > +{ > + struct pci_dev *pdev = to_pci_dev(mhi_cntrl->cntrl_dev); > + u16 vendor = 0; > + > + if (pci_read_config_word(pdev, PCI_VENDOR_ID, &vendor)) > + return false; > + > + if (vendor == (u16) ~0 || vendor == 0) > + return false; > + > + return true; > +} > + > static int mhi_pci_claim(struct mhi_controller *mhi_cntrl, > unsigned int bar_num, u64 dma_mask) > { > @@ -298,16 +323,18 @@ 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; > const struct mhi_controller_config *mhi_cntrl_config; > + struct mhi_pci_device *mhi_pdev; > struct mhi_controller *mhi_cntrl; > int err; > > dev_dbg(&pdev->dev, "MHI PCI device found: %s\n", info->name); > > - mhi_cntrl = mhi_alloc_controller(); > - if (!mhi_cntrl) Not recommended. > + mhi_pdev = devm_kzalloc(&pdev->dev, sizeof(*mhi_pdev), GFP_KERNEL); > + if (!mhi_pdev) > return -ENOMEM; Why move away from the mhi_alloc_controller/mhi_free_controller pair we recommended for use? > > mhi_cntrl_config = info->config; > + mhi_cntrl = &mhi_pdev->mhi_cntrl; > mhi_cntrl->cntrl_dev = &pdev->dev; > mhi_cntrl->iova_start = 0; > mhi_cntrl->iova_stop = DMA_BIT_MASK(info->dma_data_width); > @@ -322,17 +349,21 @@ static int mhi_pci_probe(struct pci_dev *pdev, > const struct pci_device_id *id) > > err = mhi_pci_claim(mhi_cntrl, info->bar_num, > DMA_BIT_MASK(info->dma_data_width)); > if (err) > - goto err_release; > + return err; > > err = mhi_pci_get_irqs(mhi_cntrl, mhi_cntrl_config); > if (err) > - goto err_release; > + return err; > + > + pci_set_drvdata(pdev, mhi_pdev); > > - pci_set_drvdata(pdev, mhi_cntrl); > + /* Have stored pci confspace at hand for restore in sudden PCI error > */ > + pci_save_state(pdev); > + mhi_pdev->pci_state = pci_store_saved_state(pdev); > > err = mhi_register_controller(mhi_cntrl, mhi_cntrl_config); > if (err) > - goto err_release; > + return err; > > /* MHI bus does not power up the controller by default */ > err = mhi_prepare_for_power_up(mhi_cntrl); > @@ -347,37 +378,97 @@ static int mhi_pci_probe(struct pci_dev *pdev, > const struct pci_device_id *id) > goto err_unprepare; > } > > + set_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status); > + > return 0; > > err_unprepare: > mhi_unprepare_after_power_down(mhi_cntrl); > err_unregister: > mhi_unregister_controller(mhi_cntrl); > -err_release: > - mhi_free_controller(mhi_cntrl); Not recommended. > > return err; > } > > static void mhi_pci_remove(struct pci_dev *pdev) > { > - struct mhi_controller *mhi_cntrl = pci_get_drvdata(pdev); > + struct mhi_pci_device *mhi_pdev = pci_get_drvdata(pdev); > + struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl; > + > + 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); > + } > > - mhi_power_down(mhi_cntrl, true); > - mhi_unprepare_after_power_down(mhi_cntrl); > mhi_unregister_controller(mhi_cntrl); > > /* MHI-layer reset could not be enough, always hard-reset the device > */ > mhi_pci_reset(mhi_cntrl); > +} > + > +void mhi_pci_reset_prepare(struct pci_dev *pdev) > +{ > + struct mhi_pci_device *mhi_pdev = pci_get_drvdata(pdev); > + struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl; > + > + dev_info(&pdev->dev, "reset\n"); > > - mhi_free_controller(mhi_cntrl); > + /* 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); > + } > + > + /* cause internal device reset */ > + mhi_pci_reset(mhi_cntrl); > + > + /* Be sure device reset has been executed */ > + msleep(500); > } > > +void mhi_pci_reset_done(struct pci_dev *pdev) > +{ > + struct mhi_pci_device *mhi_pdev = pci_get_drvdata(pdev); > + struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl; > + int err; > + > + /* Restore initial known working PCI state */ > + pci_load_saved_state(pdev, mhi_pdev->pci_state); > + pci_restore_state(pdev); > + > + /* Is device status available ? */ > + if (!mhi_pci_is_alive(mhi_cntrl)) { > + dev_err(&pdev->dev, "reset failed\n"); > + return; > + } > + > + err = mhi_prepare_for_power_up(mhi_cntrl); > + if (err) { > + dev_err(&pdev->dev, "failed to prepare MHI controller\n"); > + return; > + } > + > + err = mhi_sync_power_up(mhi_cntrl); > + if (err) { > + dev_err(&pdev->dev, "failed to power up MHI controller\n"); > + mhi_unprepare_after_power_down(mhi_cntrl); > + return; > + } > + > + set_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status); > +} > + > +static const struct pci_error_handlers mhi_pci_err_handler = { > + .reset_prepare = mhi_pci_reset_prepare, > + .reset_done = mhi_pci_reset_done, > +}; > + > 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 > + .remove = mhi_pci_remove, > + .err_handler = &mhi_pci_err_handler, > }; > module_pci_driver(mhi_pci_driver);
Hi Bhaumik, On Fri, 13 Nov 2020 at 18:12, Bhaumik Bhatt <bbhatt@codeaurora.org> wrote: > > On 2020-11-13 06:59, Loic Poulain wrote: > > Add support for resetting the device, reset can be triggered in case > > of error or manually via sysfs (/sys/bus/pci/devices/*/reset). > > > > Signed-off-by: Loic Poulain <loic.poulain@linaro.org> > > --- > > drivers/bus/mhi/pci_generic.c | 117 > > +++++++++++++++++++++++++++++++++++++----- > > 1 file changed, 104 insertions(+), 13 deletions(-) > > > > diff --git a/drivers/bus/mhi/pci_generic.c > > b/drivers/bus/mhi/pci_generic.c > > index 0c07cf5..b48c382 100644 > > --- a/drivers/bus/mhi/pci_generic.c > > +++ b/drivers/bus/mhi/pci_generic.c > > @@ -8,6 +8,7 @@ > > * Copyright (C) 2020 Linaro Ltd <loic.poulain@linaro.org> > > */ > > > > +#include <linux/delay.h> > > #include <linux/device.h> > > #include <linux/mhi.h> > > #include <linux/module.h> > > @@ -179,6 +180,16 @@ static const struct pci_device_id > > mhi_pci_id_table[] = { > > }; > > MODULE_DEVICE_TABLE(pci, mhi_pci_id_table); > > > > +enum mhi_pci_device_status { > > + MHI_PCI_DEV_STARTED, > > +}; > > + > > +struct mhi_pci_device { > > + struct mhi_controller mhi_cntrl; > > + struct pci_saved_state *pci_state; > > + unsigned long status; > > +}; > > + > > static int mhi_pci_read_reg(struct mhi_controller *mhi_cntrl, > > void __iomem *addr, u32 *out) > > { > > @@ -203,6 +214,20 @@ static inline void mhi_pci_reset(struct > > mhi_controller *mhi_cntrl) > > writel(1, mhi_cntrl->regs + DEV_RESET_REG); > > } > > > > +static bool mhi_pci_is_alive(struct mhi_controller *mhi_cntrl) > > +{ > > + struct pci_dev *pdev = to_pci_dev(mhi_cntrl->cntrl_dev); > > + u16 vendor = 0; > > + > > + if (pci_read_config_word(pdev, PCI_VENDOR_ID, &vendor)) > > + return false; > > + > > + if (vendor == (u16) ~0 || vendor == 0) > > + return false; > > + > > + return true; > > +} > > + > > static int mhi_pci_claim(struct mhi_controller *mhi_cntrl, > > unsigned int bar_num, u64 dma_mask) > > { > > @@ -298,16 +323,18 @@ 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; > > const struct mhi_controller_config *mhi_cntrl_config; > > + struct mhi_pci_device *mhi_pdev; > > struct mhi_controller *mhi_cntrl; > > int err; > > > > dev_dbg(&pdev->dev, "MHI PCI device found: %s\n", info->name); > > > > - mhi_cntrl = mhi_alloc_controller(); > > - if (!mhi_cntrl) > Not recommended. > > + mhi_pdev = devm_kzalloc(&pdev->dev, sizeof(*mhi_pdev), GFP_KERNEL); > > + if (!mhi_pdev) > > return -ENOMEM; > Why move away from the mhi_alloc_controller/mhi_free_controller pair we > recommended for use? Because now I don't allocate mhi controller separately, it's part of the allocated mhi_pci_device that inherit from it. If necessary we would need something like mhi_init_controller() to initialize the field, but AFAIU everything needs to be zeroed. Regards, Loic
On 2020-11-13 09:42, Loic Poulain wrote: > Hi Bhaumik, > > On Fri, 13 Nov 2020 at 18:12, Bhaumik Bhatt <bbhatt@codeaurora.org> > wrote: >> >> On 2020-11-13 06:59, Loic Poulain wrote: >> > Add support for resetting the device, reset can be triggered in case >> > of error or manually via sysfs (/sys/bus/pci/devices/*/reset). >> > >> > Signed-off-by: Loic Poulain <loic.poulain@linaro.org> >> > --- >> > drivers/bus/mhi/pci_generic.c | 117 >> > +++++++++++++++++++++++++++++++++++++----- >> > 1 file changed, 104 insertions(+), 13 deletions(-) >> > >> > diff --git a/drivers/bus/mhi/pci_generic.c >> > b/drivers/bus/mhi/pci_generic.c >> > index 0c07cf5..b48c382 100644 >> > --- a/drivers/bus/mhi/pci_generic.c >> > +++ b/drivers/bus/mhi/pci_generic.c >> > @@ -8,6 +8,7 @@ >> > * Copyright (C) 2020 Linaro Ltd <loic.poulain@linaro.org> >> > */ >> > >> > +#include <linux/delay.h> >> > #include <linux/device.h> >> > #include <linux/mhi.h> >> > #include <linux/module.h> >> > @@ -179,6 +180,16 @@ static const struct pci_device_id >> > mhi_pci_id_table[] = { >> > }; >> > MODULE_DEVICE_TABLE(pci, mhi_pci_id_table); >> > >> > +enum mhi_pci_device_status { >> > + MHI_PCI_DEV_STARTED, >> > +}; >> > + >> > +struct mhi_pci_device { >> > + struct mhi_controller mhi_cntrl; >> > + struct pci_saved_state *pci_state; >> > + unsigned long status; >> > +}; >> > + >> > static int mhi_pci_read_reg(struct mhi_controller *mhi_cntrl, >> > void __iomem *addr, u32 *out) >> > { >> > @@ -203,6 +214,20 @@ static inline void mhi_pci_reset(struct >> > mhi_controller *mhi_cntrl) >> > writel(1, mhi_cntrl->regs + DEV_RESET_REG); >> > } >> > >> > +static bool mhi_pci_is_alive(struct mhi_controller *mhi_cntrl) >> > +{ >> > + struct pci_dev *pdev = to_pci_dev(mhi_cntrl->cntrl_dev); >> > + u16 vendor = 0; >> > + >> > + if (pci_read_config_word(pdev, PCI_VENDOR_ID, &vendor)) >> > + return false; >> > + >> > + if (vendor == (u16) ~0 || vendor == 0) >> > + return false; >> > + >> > + return true; >> > +} >> > + >> > static int mhi_pci_claim(struct mhi_controller *mhi_cntrl, >> > unsigned int bar_num, u64 dma_mask) >> > { >> > @@ -298,16 +323,18 @@ 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; >> > const struct mhi_controller_config *mhi_cntrl_config; >> > + struct mhi_pci_device *mhi_pdev; >> > struct mhi_controller *mhi_cntrl; >> > int err; >> > >> > dev_dbg(&pdev->dev, "MHI PCI device found: %s\n", info->name); >> > >> > - mhi_cntrl = mhi_alloc_controller(); >> > - if (!mhi_cntrl) >> Not recommended. >> > + mhi_pdev = devm_kzalloc(&pdev->dev, sizeof(*mhi_pdev), GFP_KERNEL); >> > + if (!mhi_pdev) >> > return -ENOMEM; >> Why move away from the mhi_alloc_controller/mhi_free_controller pair >> we >> recommended for use? > > Because now I don't allocate mhi controller separately, it's part of > the allocated mhi_pci_device that inherit from it. If necessary we > would need something like mhi_init_controller() to initialize the > field, but AFAIU everything needs to be zeroed. Let's make sure we use the mhi_alloc/free_controller APIs because it will help us have better control in case we need track of some allocations. > > Regards, > Loic
diff --git a/drivers/bus/mhi/pci_generic.c b/drivers/bus/mhi/pci_generic.c index 0c07cf5..b48c382 100644 --- a/drivers/bus/mhi/pci_generic.c +++ b/drivers/bus/mhi/pci_generic.c @@ -8,6 +8,7 @@ * Copyright (C) 2020 Linaro Ltd <loic.poulain@linaro.org> */ +#include <linux/delay.h> #include <linux/device.h> #include <linux/mhi.h> #include <linux/module.h> @@ -179,6 +180,16 @@ static const struct pci_device_id mhi_pci_id_table[] = { }; MODULE_DEVICE_TABLE(pci, mhi_pci_id_table); +enum mhi_pci_device_status { + MHI_PCI_DEV_STARTED, +}; + +struct mhi_pci_device { + struct mhi_controller mhi_cntrl; + struct pci_saved_state *pci_state; + unsigned long status; +}; + static int mhi_pci_read_reg(struct mhi_controller *mhi_cntrl, void __iomem *addr, u32 *out) { @@ -203,6 +214,20 @@ static inline void mhi_pci_reset(struct mhi_controller *mhi_cntrl) writel(1, mhi_cntrl->regs + DEV_RESET_REG); } +static bool mhi_pci_is_alive(struct mhi_controller *mhi_cntrl) +{ + struct pci_dev *pdev = to_pci_dev(mhi_cntrl->cntrl_dev); + u16 vendor = 0; + + if (pci_read_config_word(pdev, PCI_VENDOR_ID, &vendor)) + return false; + + if (vendor == (u16) ~0 || vendor == 0) + return false; + + return true; +} + static int mhi_pci_claim(struct mhi_controller *mhi_cntrl, unsigned int bar_num, u64 dma_mask) { @@ -298,16 +323,18 @@ 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; const struct mhi_controller_config *mhi_cntrl_config; + struct mhi_pci_device *mhi_pdev; struct mhi_controller *mhi_cntrl; int err; dev_dbg(&pdev->dev, "MHI PCI device found: %s\n", info->name); - mhi_cntrl = mhi_alloc_controller(); - if (!mhi_cntrl) + mhi_pdev = devm_kzalloc(&pdev->dev, sizeof(*mhi_pdev), GFP_KERNEL); + if (!mhi_pdev) return -ENOMEM; mhi_cntrl_config = info->config; + mhi_cntrl = &mhi_pdev->mhi_cntrl; mhi_cntrl->cntrl_dev = &pdev->dev; mhi_cntrl->iova_start = 0; mhi_cntrl->iova_stop = DMA_BIT_MASK(info->dma_data_width); @@ -322,17 +349,21 @@ static int mhi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) err = mhi_pci_claim(mhi_cntrl, info->bar_num, DMA_BIT_MASK(info->dma_data_width)); if (err) - goto err_release; + return err; err = mhi_pci_get_irqs(mhi_cntrl, mhi_cntrl_config); if (err) - goto err_release; + return err; + + pci_set_drvdata(pdev, mhi_pdev); - pci_set_drvdata(pdev, mhi_cntrl); + /* Have stored pci confspace at hand for restore in sudden PCI error */ + pci_save_state(pdev); + mhi_pdev->pci_state = pci_store_saved_state(pdev); err = mhi_register_controller(mhi_cntrl, mhi_cntrl_config); if (err) - goto err_release; + return err; /* MHI bus does not power up the controller by default */ err = mhi_prepare_for_power_up(mhi_cntrl); @@ -347,37 +378,97 @@ static int mhi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) goto err_unprepare; } + set_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status); + return 0; err_unprepare: mhi_unprepare_after_power_down(mhi_cntrl); err_unregister: mhi_unregister_controller(mhi_cntrl); -err_release: - mhi_free_controller(mhi_cntrl); return err; } static void mhi_pci_remove(struct pci_dev *pdev) { - struct mhi_controller *mhi_cntrl = pci_get_drvdata(pdev); + struct mhi_pci_device *mhi_pdev = pci_get_drvdata(pdev); + struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl; + + 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); + } - mhi_power_down(mhi_cntrl, true); - mhi_unprepare_after_power_down(mhi_cntrl); mhi_unregister_controller(mhi_cntrl); /* MHI-layer reset could not be enough, always hard-reset the device */ mhi_pci_reset(mhi_cntrl); +} + +void mhi_pci_reset_prepare(struct pci_dev *pdev) +{ + struct mhi_pci_device *mhi_pdev = pci_get_drvdata(pdev); + struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl; + + dev_info(&pdev->dev, "reset\n"); - mhi_free_controller(mhi_cntrl); + /* 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); + } + + /* cause internal device reset */ + mhi_pci_reset(mhi_cntrl); + + /* Be sure device reset has been executed */ + msleep(500); } +void mhi_pci_reset_done(struct pci_dev *pdev) +{ + struct mhi_pci_device *mhi_pdev = pci_get_drvdata(pdev); + struct mhi_controller *mhi_cntrl = &mhi_pdev->mhi_cntrl; + int err; + + /* Restore initial known working PCI state */ + pci_load_saved_state(pdev, mhi_pdev->pci_state); + pci_restore_state(pdev); + + /* Is device status available ? */ + if (!mhi_pci_is_alive(mhi_cntrl)) { + dev_err(&pdev->dev, "reset failed\n"); + return; + } + + err = mhi_prepare_for_power_up(mhi_cntrl); + if (err) { + dev_err(&pdev->dev, "failed to prepare MHI controller\n"); + return; + } + + err = mhi_sync_power_up(mhi_cntrl); + if (err) { + dev_err(&pdev->dev, "failed to power up MHI controller\n"); + mhi_unprepare_after_power_down(mhi_cntrl); + return; + } + + set_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status); +} + +static const struct pci_error_handlers mhi_pci_err_handler = { + .reset_prepare = mhi_pci_reset_prepare, + .reset_done = mhi_pci_reset_done, +}; + 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 + .remove = mhi_pci_remove, + .err_handler = &mhi_pci_err_handler, }; module_pci_driver(mhi_pci_driver);
Add support for resetting the device, reset can be triggered in case of error or manually via sysfs (/sys/bus/pci/devices/*/reset). Signed-off-by: Loic Poulain <loic.poulain@linaro.org> --- drivers/bus/mhi/pci_generic.c | 117 +++++++++++++++++++++++++++++++++++++----- 1 file changed, 104 insertions(+), 13 deletions(-)