| Message ID | 1516185438-31556-5-git-send-email-poza@codeaurora.org (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
On 1/17/2018 5:37 AM, Oza Pawandeep wrote: > +static bool dpc_wait_link_active(struct pci_dev *pdev) > +{ I think you can also make this function common instead of making another copy here. Of course, this would be another patch.
On Wed, Jan 17, 2018 at 08:27:39AM -0800, Sinan Kaya wrote: > On 1/17/2018 5:37 AM, Oza Pawandeep wrote: > > +static bool dpc_wait_link_active(struct pci_dev *pdev) > > +{ > > I think you can also make this function common instead of making another copy here. > Of course, this would be another patch. It is actually very similar to __pcie_wait_link_active in pciehp_hpc.c, so there's some opprotunity to make even more common code.
On 2018-01-17 21:57, Sinan Kaya wrote: > On 1/17/2018 5:37 AM, Oza Pawandeep wrote: >> +static bool dpc_wait_link_active(struct pci_dev *pdev) >> +{ > > I think you can also make this function common instead of making > another copy here. > Of course, this would be another patch. ok I will make a separate patch taking one more parameter dpc_wait_link_active(struct pci_dev *, bool) if not in this series, then immediate one. Regards, Oza.
On 2018-01-18 08:26, Keith Busch wrote: > On Wed, Jan 17, 2018 at 08:27:39AM -0800, Sinan Kaya wrote: >> On 1/17/2018 5:37 AM, Oza Pawandeep wrote: >> > +static bool dpc_wait_link_active(struct pci_dev *pdev) >> > +{ >> >> I think you can also make this function common instead of making >> another copy here. >> Of course, this would be another patch. > > It is actually very similar to __pcie_wait_link_active in pciehp_hpc.c, > so there's some opprotunity to make even more common code. in that case there has to be a generic function in drives/pci.c which addresses folowing functions from pcie-dpc.c: dpc_wait_link_inactive dpc_wait_link_active drivers/pci/hotplug/pciehp_hpc.c pcie_wait_link_active all aboe making one generic function to be moved to drives/pci.c please let me know if this is okay. Regards, Oza.
On 1/18/2018 12:32 AM, poza@codeaurora.org wrote: > On 2018-01-18 08:26, Keith Busch wrote: >> On Wed, Jan 17, 2018 at 08:27:39AM -0800, Sinan Kaya wrote: >>> On 1/17/2018 5:37 AM, Oza Pawandeep wrote: >>> > +static bool dpc_wait_link_active(struct pci_dev *pdev) >>> > +{ >>> >>> I think you can also make this function common instead of making another copy here. >>> Of course, this would be another patch. >> >> It is actually very similar to __pcie_wait_link_active in pciehp_hpc.c, >> so there's some opprotunity to make even more common code. > > in that case there has to be a generic function in > drives/pci.c > > which addresses folowing functions from > > pcie-dpc.c: > dpc_wait_link_inactive > dpc_wait_link_active > > drivers/pci/hotplug/pciehp_hpc.c > pcie_wait_link_active > > > all aboe making one generic function to be moved to drives/pci.c > > please let me know if this is okay. Works for me. Keith/Bjorn? > > Regards, > Oza. > >
On Thu, Jan 18, 2018 at 11:35:59AM -0500, Sinan Kaya wrote: > On 1/18/2018 12:32 AM, poza@codeaurora.org wrote: > > On 2018-01-18 08:26, Keith Busch wrote: > >> On Wed, Jan 17, 2018 at 08:27:39AM -0800, Sinan Kaya wrote: > >>> On 1/17/2018 5:37 AM, Oza Pawandeep wrote: > >>> > +static bool dpc_wait_link_active(struct pci_dev *pdev) > >>> > +{ > >>> > >>> I think you can also make this function common instead of making another copy here. > >>> Of course, this would be another patch. > >> > >> It is actually very similar to __pcie_wait_link_active in pciehp_hpc.c, > >> so there's some opprotunity to make even more common code. > > > > in that case there has to be a generic function in > > drives/pci.c > > > > which addresses folowing functions from > > > > pcie-dpc.c: > > dpc_wait_link_inactive > > dpc_wait_link_active > > > > drivers/pci/hotplug/pciehp_hpc.c > > pcie_wait_link_active > > > > > > all aboe making one generic function to be moved to drives/pci.c > > > > please let me know if this is okay. > > Works for me. Keith/Bjorn? Yep, I believe common solutions that reduce code is always encouraged in the Linux kernel.
On 2018-01-19 07:13, Keith Busch wrote: > On Thu, Jan 18, 2018 at 11:35:59AM -0500, Sinan Kaya wrote: >> On 1/18/2018 12:32 AM, poza@codeaurora.org wrote: >> > On 2018-01-18 08:26, Keith Busch wrote: >> >> On Wed, Jan 17, 2018 at 08:27:39AM -0800, Sinan Kaya wrote: >> >>> On 1/17/2018 5:37 AM, Oza Pawandeep wrote: >> >>> > +static bool dpc_wait_link_active(struct pci_dev *pdev) >> >>> > +{ >> >>> >> >>> I think you can also make this function common instead of making another copy here. >> >>> Of course, this would be another patch. >> >> >> >> It is actually very similar to __pcie_wait_link_active in pciehp_hpc.c, >> >> so there's some opprotunity to make even more common code. >> > >> > in that case there has to be a generic function in >> > drives/pci.c >> > >> > which addresses folowing functions from >> > >> > pcie-dpc.c: >> > dpc_wait_link_inactive >> > dpc_wait_link_active >> > >> > drivers/pci/hotplug/pciehp_hpc.c >> > pcie_wait_link_active >> > >> > >> > all aboe making one generic function to be moved to drives/pci.c >> > >> > please let me know if this is okay. >> >> Works for me. Keith/Bjorn? > > Yep, I believe common solutions that reduce code is always encouraged > in the Linux kernel. okay, I will work on this. Regards, Oza.
diff --git a/drivers/pci/pcie/pcie-dpc.c b/drivers/pci/pcie/pcie-dpc.c index ed916765..f99adcae 100644 --- a/drivers/pci/pcie/pcie-dpc.c +++ b/drivers/pci/pcie/pcie-dpc.c @@ -162,6 +162,43 @@ static void dpc_wait_link_inactive(struct dpc_dev *dpc) dev_warn(dev, "Link state not disabled for DPC event\n"); } +static bool dpc_wait_link_active(struct pci_dev *pdev) +{ + unsigned long timeout = jiffies + HZ; + u16 lnk_status; + bool ret = true; + + pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status); + + while (!(lnk_status & PCI_EXP_LNKSTA_DLLLA) && + !time_after(jiffies, timeout)) { + msleep(10); + pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status); + } + + if (!(lnk_status & PCI_EXP_LNKSTA_DLLLA)) { + dev_warn(&pdev->dev, "Link state not enabled after DPC event\n"); + ret = false; + } + + return ret; +} + +/** + * dpc_error_resume - enumerate the devices beneath + * @dev: pointer to Root Port's pci_dev data structure + * + * Invoked by Port Bus driver during nonfatal recovery. + */ +static void dpc_error_resume(struct pci_dev *pdev) +{ + if (dpc_wait_link_active(pdev)) { + pci_lock_rescan_remove(); + pci_rescan_bus(pdev->bus); + pci_unlock_rescan_remove(); + } +} + /** * dpc_reset_link - reset link DPC routine * @dev: pointer to Root Port's pci_dev data structure @@ -420,6 +457,7 @@ static void dpc_remove(struct pcie_device *dev) .service = PCIE_PORT_SERVICE_DPC, .probe = dpc_probe, .remove = dpc_remove, + .error_resume = dpc_error_resume, .reset_link = dpc_reset_link, }; diff --git a/drivers/pci/pcie/pcie-err.c b/drivers/pci/pcie/pcie-err.c index 8ce1de1..de72b0a 100644 --- a/drivers/pci/pcie/pcie-err.c +++ b/drivers/pci/pcie/pcie-err.c @@ -236,6 +236,7 @@ static pci_ers_result_t reset_link(struct pci_dev *dev, int severity) * @state: error state * @error_mesg: message to print * @cb: callback to be broadcasted + * @severity: error severity * * Invoked during error recovery process. Once being invoked, the content * of error severity will be broadcasted to all downstream drivers in a @@ -244,7 +245,8 @@ static pci_ers_result_t reset_link(struct pci_dev *dev, int severity) static pci_ers_result_t broadcast_error_message(struct pci_dev *dev, enum pci_channel_state state, char *error_mesg, - int (*cb)(struct pci_dev *, void *)) + int (*cb)(struct pci_dev *, void *), + int severity) { struct aer_broadcast_data result_data; @@ -256,6 +258,15 @@ static pci_ers_result_t broadcast_error_message(struct pci_dev *dev, result_data.result = PCI_ERS_RESULT_RECOVERED; if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) { + /* If DPC is triggered, call resume error hanlder + * because, at this point we can safely assume that + * link recovery has happened. + */ + if ((severity == DPC_FATAL) && + (cb == report_resume)) { + cb(dev, NULL); + return PCI_ERS_RESULT_RECOVERED; + } /* * If the error is reported by a bridge, we think this error * is related to the downstream link of the bridge, so we @@ -305,7 +316,8 @@ void pci_do_recovery(struct pci_dev *dev, int severity) status = broadcast_error_message(dev, state, "error_detected", - report_error_detected); + report_error_detected, + severity); if ((severity == AER_FATAL) || (severity == DPC_FATAL)) { @@ -318,7 +330,8 @@ void pci_do_recovery(struct pci_dev *dev, int severity) status = broadcast_error_message(dev, state, "mmio_enabled", - report_mmio_enabled); + report_mmio_enabled, + severity); if (status == PCI_ERS_RESULT_NEED_RESET) { /* @@ -329,7 +342,8 @@ void pci_do_recovery(struct pci_dev *dev, int severity) status = broadcast_error_message(dev, state, "slot_reset", - report_slot_reset); + report_slot_reset, + severity); } if (status != PCI_ERS_RESULT_RECOVERED) @@ -338,7 +352,8 @@ void pci_do_recovery(struct pci_dev *dev, int severity) broadcast_error_message(dev, state, "resume", - report_resume); + report_resume, + severity); dev_info(&dev->dev, "Device recovery successful\n"); mutex_unlock(&pci_err_recovery_lock);
Implement error_resume callback in DPC so, after DPC trigger event enumerates the devices beneath. Signed-off-by: Oza Pawandeep <poza@codeaurora.org>