From 7fd1fe4e4811f52b854647b8ff324745135224a5 Mon Sep 17 00:00:00 2001 From: Oliver O'Halloran Date: Tue, 3 Sep 2019 20:15:59 +1000 Subject: [PATCH] pci-hotplug/pnv_php: Add a reset_slot() callback When performing EEH recovery of devices in a hotplug slot we need to use the slot driver's ->reset_slot() callback to prevent spurious hotplug events due to spurious DLActive and PresDet change interrupts. Add a reset_slot() callback to pnv_php so we can handle recovery of devices in pnv_php managed slots. Signed-off-by: Oliver O'Halloran Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20190903101605.2890-9-oohall@gmail.com --- drivers/pci/hotplug/pnv_php.c | 39 +++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) diff --git a/drivers/pci/hotplug/pnv_php.c b/drivers/pci/hotplug/pnv_php.c index 6758fd7c382e..b0e243dabf77 100644 --- a/drivers/pci/hotplug/pnv_php.c +++ b/drivers/pci/hotplug/pnv_php.c @@ -511,6 +511,37 @@ scan: return 0; } +static int pnv_php_reset_slot(struct hotplug_slot *slot, int probe) +{ + struct pnv_php_slot *php_slot = to_pnv_php_slot(slot); + struct pci_dev *bridge = php_slot->pdev; + uint16_t sts; + + /* + * The CAPI folks want pnv_php to drive OpenCAPI slots + * which don't have a bridge. Only claim to support + * reset_slot() if we have a bridge device (for now...) + */ + if (probe) + return !bridge; + + /* mask our interrupt while resetting the bridge */ + if (php_slot->irq > 0) + disable_irq(php_slot->irq); + + pci_bridge_secondary_bus_reset(bridge); + + /* clear any state changes that happened due to the reset */ + pcie_capability_read_word(php_slot->pdev, PCI_EXP_SLTSTA, &sts); + sts &= (PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_DLLSC); + pcie_capability_write_word(php_slot->pdev, PCI_EXP_SLTSTA, sts); + + if (php_slot->irq > 0) + enable_irq(php_slot->irq); + + return 0; +} + static int pnv_php_enable_slot(struct hotplug_slot *slot) { struct pnv_php_slot *php_slot = to_pnv_php_slot(slot); @@ -548,6 +579,7 @@ static const struct hotplug_slot_ops php_slot_ops = { .set_attention_status = pnv_php_set_attention_state, .enable_slot = pnv_php_enable_slot, .disable_slot = pnv_php_disable_slot, + .reset_slot = pnv_php_reset_slot, }; static void pnv_php_release(struct pnv_php_slot *php_slot) @@ -721,6 +753,12 @@ static irqreturn_t pnv_php_interrupt(int irq, void *data) pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &sts); sts &= (PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_DLLSC); pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, sts); + + pci_dbg(pdev, "PCI slot [%s]: HP int! DLAct: %d, PresDet: %d\n", + php_slot->name, + !!(sts & PCI_EXP_SLTSTA_DLLSC), + !!(sts & PCI_EXP_SLTSTA_PDC)); + if (sts & PCI_EXP_SLTSTA_DLLSC) { pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lsts); added = !!(lsts & PCI_EXP_LNKSTA_DLLLA); @@ -735,6 +773,7 @@ static irqreturn_t pnv_php_interrupt(int irq, void *data) added = !!(presence == OPAL_PCI_SLOT_PRESENT); } else { + pci_dbg(pdev, "PCI slot [%s]: Spurious IRQ?\n", php_slot->name); return IRQ_NONE; } -- 2.30.2