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commit 9936328b41ce4bce8f20269dcac8cb476c8d0820
parent 8c7ae38d1ce12a0eaeba655df8562552b3596c7f
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date:   Thu, 28 Mar 2019 13:29:09 -0700

Merge tag 'pci-v5.1-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI fixes from Bjorn Helgaas:
 "PCI fixes:

   - Clear level-triggered interrupts for the bandwidth notification
     supported added for v5.1 (Alexandru Gagniuc)

   - Clear bandwidth notification interrupts before enabling them (Lukas
     Wunner)

   - Report post-enumeration bandwidth changes only once for
     multi-function devices (Lukas Wunner)"

* tag 'pci-v5.1-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  PCI/LINK: Deduplicate bandwidth reports for multi-function devices
  PCI/LINK: Clear bandwidth notification interrupt before enabling it
  PCI/LINK: Supply IRQ handler so level-triggered IRQs are acked

Diffstat:
Mdrivers/pci/pci.h | 1+
Mdrivers/pci/pcie/bw_notification.c | 23+++++++++++++++++------
Mdrivers/pci/probe.c | 2+-
3 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h @@ -273,6 +273,7 @@ enum pcie_link_width pcie_get_width_cap(struct pci_dev *dev); u32 pcie_bandwidth_capable(struct pci_dev *dev, enum pci_bus_speed *speed, enum pcie_link_width *width); void __pcie_print_link_status(struct pci_dev *dev, bool verbose); +void pcie_report_downtraining(struct pci_dev *dev); /* Single Root I/O Virtualization */ struct pci_sriov { diff --git a/drivers/pci/pcie/bw_notification.c b/drivers/pci/pcie/bw_notification.c @@ -30,6 +30,8 @@ static void pcie_enable_link_bandwidth_notification(struct pci_dev *dev) { u16 lnk_ctl; + pcie_capability_write_word(dev, PCI_EXP_LNKSTA, PCI_EXP_LNKSTA_LBMS); + pcie_capability_read_word(dev, PCI_EXP_LNKCTL, &lnk_ctl); lnk_ctl |= PCI_EXP_LNKCTL_LBMIE; pcie_capability_write_word(dev, PCI_EXP_LNKCTL, lnk_ctl); @@ -44,11 +46,10 @@ static void pcie_disable_link_bandwidth_notification(struct pci_dev *dev) pcie_capability_write_word(dev, PCI_EXP_LNKCTL, lnk_ctl); } -static irqreturn_t pcie_bw_notification_handler(int irq, void *context) +static irqreturn_t pcie_bw_notification_irq(int irq, void *context) { struct pcie_device *srv = context; struct pci_dev *port = srv->port; - struct pci_dev *dev; u16 link_status, events; int ret; @@ -58,17 +59,26 @@ static irqreturn_t pcie_bw_notification_handler(int irq, void *context) if (ret != PCIBIOS_SUCCESSFUL || !events) return IRQ_NONE; + pcie_capability_write_word(port, PCI_EXP_LNKSTA, events); + pcie_update_link_speed(port->subordinate, link_status); + return IRQ_WAKE_THREAD; +} + +static irqreturn_t pcie_bw_notification_handler(int irq, void *context) +{ + struct pcie_device *srv = context; + struct pci_dev *port = srv->port; + struct pci_dev *dev; + /* * Print status from downstream devices, not this root port or * downstream switch port. */ down_read(&pci_bus_sem); list_for_each_entry(dev, &port->subordinate->devices, bus_list) - __pcie_print_link_status(dev, false); + pcie_report_downtraining(dev); up_read(&pci_bus_sem); - pcie_update_link_speed(port->subordinate, link_status); - pcie_capability_write_word(port, PCI_EXP_LNKSTA, events); return IRQ_HANDLED; } @@ -80,7 +90,8 @@ static int pcie_bandwidth_notification_probe(struct pcie_device *srv) if (!pcie_link_bandwidth_notification_supported(srv->port)) return -ENODEV; - ret = request_threaded_irq(srv->irq, NULL, pcie_bw_notification_handler, + ret = request_threaded_irq(srv->irq, pcie_bw_notification_irq, + pcie_bw_notification_handler, IRQF_SHARED, "PCIe BW notif", srv); if (ret) return ret; diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c @@ -2388,7 +2388,7 @@ static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn) return dev; } -static void pcie_report_downtraining(struct pci_dev *dev) +void pcie_report_downtraining(struct pci_dev *dev) { if (!pci_is_pcie(dev)) return;