From 91295d79d65892eabd02a2a75fd4ac88197d17a1 Mon Sep 17 00:00:00 2001 From: Sinan Kaya Date: Tue, 27 Feb 2018 14:14:08 -0600 Subject: [PATCH] PCI: Handle FLR failure and allow other reset types pci_flr_wait() and pci_af_flr() functions assume graceful return even though the device is inaccessible under error conditions. Return -ENOTTY in error cases so that __pci_reset_function_locked() can try other reset types if AF_FLR/FLR reset fails. Signed-off-by: Sinan Kaya Signed-off-by: Bjorn Helgaas Reviewed-by: Christoph Hellwig --- drivers/pci/pci.c | 18 ++++++++++-------- include/linux/pci.h | 2 +- 2 files changed, 11 insertions(+), 9 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 660c848aa14a..7aa11b1fbee3 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -4017,7 +4017,7 @@ int pci_wait_for_pending_transaction(struct pci_dev *dev) } EXPORT_SYMBOL(pci_wait_for_pending_transaction); -static void pci_flr_wait(struct pci_dev *dev) +static int pci_flr_wait(struct pci_dev *dev) { int delay = 1, timeout = 60000; u32 id; @@ -4046,7 +4046,7 @@ static void pci_flr_wait(struct pci_dev *dev) if (delay > timeout) { pci_warn(dev, "not ready %dms after FLR; giving up\n", 100 + delay - 1); - return; + return -ENOTTY; } if (delay > 1000) @@ -4060,6 +4060,8 @@ static void pci_flr_wait(struct pci_dev *dev) if (delay > 1000) pci_info(dev, "ready %dms after FLR\n", 100 + delay - 1); + + return 0; } /** @@ -4088,13 +4090,13 @@ static bool pcie_has_flr(struct pci_dev *dev) * device supports FLR before calling this function, e.g. by using the * pcie_has_flr() helper. */ -void pcie_flr(struct pci_dev *dev) +int pcie_flr(struct pci_dev *dev) { if (!pci_wait_for_pending_transaction(dev)) pci_err(dev, "timed out waiting for pending transaction; performing function level reset anyway\n"); pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_DEVCTL_BCR_FLR); - pci_flr_wait(dev); + return pci_flr_wait(dev); } EXPORT_SYMBOL_GPL(pcie_flr); @@ -4127,8 +4129,7 @@ static int pci_af_flr(struct pci_dev *dev, int probe) pci_err(dev, "timed out waiting for pending transaction; performing AF function level reset anyway\n"); pci_write_config_byte(dev, pos + PCI_AF_CTRL, PCI_AF_CTRL_FLR); - pci_flr_wait(dev); - return 0; + return pci_flr_wait(dev); } /** @@ -4379,8 +4380,9 @@ int __pci_reset_function_locked(struct pci_dev *dev) if (rc != -ENOTTY) return rc; if (pcie_has_flr(dev)) { - pcie_flr(dev); - return 0; + rc = pcie_flr(dev); + if (rc != -ENOTTY) + return rc; } rc = pci_af_flr(dev, 0); if (rc != -ENOTTY) diff --git a/include/linux/pci.h b/include/linux/pci.h index 024a1beda008..af75d9d76189 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1082,7 +1082,7 @@ int pcie_get_mps(struct pci_dev *dev); int pcie_set_mps(struct pci_dev *dev, int mps); int pcie_get_minimum_link(struct pci_dev *dev, enum pci_bus_speed *speed, enum pcie_link_width *width); -void pcie_flr(struct pci_dev *dev); +int pcie_flr(struct pci_dev *dev); int __pci_reset_function_locked(struct pci_dev *dev); int pci_reset_function(struct pci_dev *dev); int pci_reset_function_locked(struct pci_dev *dev);