From 9f5a70f18c5893a30d6c339adc48de43c57dd7e2 Mon Sep 17 00:00:00 2001 From: Oza Pawandeep Date: Thu, 17 May 2018 16:44:11 -0500 Subject: PCI: Add generic pcie_wait_for_link() interface Clients such as hotplug and Downstream Port Containment (DPC) both need to wait until a link becomes active or inactive. Add a generic pcie_wait_link_active() interface and use it instead of duplicating the code. Signed-off-by: Oza Pawandeep Signed-off-by: Bjorn Helgaas Reviewed-by: Keith Busch --- drivers/pci/hotplug/pciehp_hpc.c | 20 +++----------------- drivers/pci/pci.c | 29 +++++++++++++++++++++++++++++ drivers/pci/pci.h | 1 + drivers/pci/pcie/dpc.c | 12 +----------- 4 files changed, 34 insertions(+), 28 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c index 18a42f8f5dc5..e0c2b8ead6cb 100644 --- a/drivers/pci/hotplug/pciehp_hpc.c +++ b/drivers/pci/hotplug/pciehp_hpc.c @@ -231,25 +231,11 @@ bool pciehp_check_link_active(struct controller *ctrl) return ret; } -static void __pcie_wait_link_active(struct controller *ctrl, bool active) -{ - int timeout = 1000; - - if (pciehp_check_link_active(ctrl) == active) - return; - while (timeout > 0) { - msleep(10); - timeout -= 10; - if (pciehp_check_link_active(ctrl) == active) - return; - } - ctrl_dbg(ctrl, "Data Link Layer Link Active not %s in 1000 msec\n", - active ? "set" : "cleared"); -} - static void pcie_wait_link_active(struct controller *ctrl) { - __pcie_wait_link_active(ctrl, true); + struct pci_dev *pdev = ctrl_dev(ctrl); + + pcie_wait_for_link(pdev, true); } static bool pci_bus_check_dev(struct pci_bus *bus, int devfn) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index e597655a5643..764bf64a097d 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -4138,6 +4138,35 @@ static int pci_pm_reset(struct pci_dev *dev, int probe) return pci_dev_wait(dev, "PM D3->D0", PCIE_RESET_READY_POLL_MS); } +/** + * pcie_wait_for_link - Wait until link is active or inactive + * @pdev: Bridge device + * @active: waiting for active or inactive? + * + * Use this to wait till link becomes active or inactive. + */ +bool pcie_wait_for_link(struct pci_dev *pdev, bool active) +{ + int timeout = 1000; + bool ret; + u16 lnk_status; + + for (;;) { + pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status); + ret = !!(lnk_status & PCI_EXP_LNKSTA_DLLLA); + if (ret == active) + return true; + if (timeout <= 0) + break; + msleep(10); + timeout -= 10; + } + + pci_info(pdev, "Data Link Layer Link Active not %s in 1000 msec\n", + active ? "set" : "cleared"); + + return false; +} void pci_reset_secondary_bus(struct pci_dev *dev) { diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 023f7cf25bff..cec9d8c2b7b8 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -353,6 +353,7 @@ static inline resource_size_t pci_resource_alignment(struct pci_dev *dev, void pci_enable_acs(struct pci_dev *dev); +bool pcie_wait_for_link(struct pci_dev *pdev, bool active); #ifdef CONFIG_PCIEASPM void pcie_aspm_init_link_state(struct pci_dev *pdev); void pcie_aspm_exit_link_state(struct pci_dev *pdev); diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c index 8c57d607e603..80ec3849f8d3 100644 --- a/drivers/pci/pcie/dpc.c +++ b/drivers/pci/pcie/dpc.c @@ -68,19 +68,9 @@ static int dpc_wait_rp_inactive(struct dpc_dev *dpc) static void dpc_wait_link_inactive(struct dpc_dev *dpc) { - unsigned long timeout = jiffies + HZ; struct pci_dev *pdev = dpc->dev->port; - struct device *dev = &dpc->dev->device; - u16 lnk_status; - 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(dev, "Link state not disabled for DPC event\n"); + pcie_wait_for_link(pdev, false); } static void dpc_work(struct work_struct *work) -- cgit v1.2.3-58-ga151