Reading an empty slot returns all ones, which triggers a false EEH error event on PowerNV.
New callbacks pcibios_rescan_prepare/done are introduced to pause/resume the EEH during rescan. Signed-off-by: Sergey Miroshnichenko <s.miroshniche...@yadro.com> --- arch/powerpc/include/asm/eeh.h | 2 ++ arch/powerpc/kernel/eeh.c | 12 +++++++++++ arch/powerpc/platforms/powernv/eeh-powernv.c | 22 ++++++++++++++++++++ drivers/pci/probe.c | 14 +++++++++++++ include/linux/pci.h | 2 ++ 5 files changed, 52 insertions(+) diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h index 219637ea69a1..926c3e31df99 100644 --- a/arch/powerpc/include/asm/eeh.h +++ b/arch/powerpc/include/asm/eeh.h @@ -219,6 +219,8 @@ struct eeh_ops { int (*next_error)(struct eeh_pe **pe); int (*restore_config)(struct pci_dn *pdn); int (*notify_resume)(struct pci_dn *pdn); + int (*pause)(struct pci_bus *bus); + int (*resume)(struct pci_bus *bus); }; extern int eeh_subsystem_flags; diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c index 6ebba3e48b01..9fb5012f389d 100644 --- a/arch/powerpc/kernel/eeh.c +++ b/arch/powerpc/kernel/eeh.c @@ -1831,3 +1831,15 @@ static int __init eeh_init_proc(void) return 0; } __initcall(eeh_init_proc); + +void pcibios_rescan_prepare(struct pci_bus *bus) +{ + if (eeh_ops && eeh_ops->pause) + eeh_ops->pause(bus); +} + +void pcibios_rescan_done(struct pci_bus *bus) +{ + if (eeh_ops && eeh_ops->resume) + eeh_ops->resume(bus); +} diff --git a/arch/powerpc/platforms/powernv/eeh-powernv.c b/arch/powerpc/platforms/powernv/eeh-powernv.c index 3c1beae29f2d..9724a58afcd2 100644 --- a/arch/powerpc/platforms/powernv/eeh-powernv.c +++ b/arch/powerpc/platforms/powernv/eeh-powernv.c @@ -59,6 +59,26 @@ void pnv_pcibios_bus_add_device(struct pci_dev *pdev) eeh_sysfs_add_device(pdev); } +static int pnv_eeh_pause(struct pci_bus *bus) +{ + struct pci_controller *hose = pci_bus_to_host(bus); + struct pnv_phb *phb = hose->private_data; + + phb->flags &= ~PNV_PHB_FLAG_EEH; + disable_irq(eeh_event_irq); + return 0; +} + +static int pnv_eeh_resume(struct pci_bus *bus) +{ + struct pci_controller *hose = pci_bus_to_host(bus); + struct pnv_phb *phb = hose->private_data; + + enable_irq(eeh_event_irq); + phb->flags |= PNV_PHB_FLAG_EEH; + return 0; +} + static int pnv_eeh_init(void) { struct pci_controller *hose; @@ -1710,6 +1730,8 @@ static struct eeh_ops pnv_eeh_ops = { .write_config = pnv_eeh_write_config, .next_error = pnv_eeh_next_error, .restore_config = pnv_eeh_restore_config, + .pause = pnv_eeh_pause, + .resume = pnv_eeh_resume, .notify_resume = NULL }; diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index ac876e32de4b..4a9045364809 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -2801,6 +2801,14 @@ void __weak pcibios_remove_bus(struct pci_bus *bus) { } +void __weak pcibios_rescan_prepare(struct pci_bus *bus) +{ +} + +void __weak pcibios_rescan_done(struct pci_bus *bus) +{ +} + struct pci_bus *pci_create_root_bus(struct device *parent, int bus, struct pci_ops *ops, void *sysdata, struct list_head *resources) { @@ -3055,9 +3063,15 @@ unsigned int pci_rescan_bus_bridge_resize(struct pci_dev *bridge) unsigned int pci_rescan_bus(struct pci_bus *bus) { unsigned int max; + struct pci_bus *root = bus; + + while (!pci_is_root_bus(root)) + root = root->parent; + pcibios_rescan_prepare(root); max = pci_scan_child_bus(bus); pci_assign_unassigned_bus_resources(bus); + pcibios_rescan_done(root); pci_bus_add_devices(bus); return max; diff --git a/include/linux/pci.h b/include/linux/pci.h index 340029b2fb38..42930731c5a7 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1929,6 +1929,8 @@ void pcibios_penalize_isa_irq(int irq, int active); int pcibios_alloc_irq(struct pci_dev *dev); void pcibios_free_irq(struct pci_dev *dev); resource_size_t pcibios_default_alignment(void); +void pcibios_rescan_prepare(struct pci_bus *bus); +void pcibios_rescan_done(struct pci_bus *bus); #ifdef CONFIG_HIBERNATE_CALLBACKS extern struct dev_pm_ops pcibios_pm_ops; -- 2.17.1