1 files changed, 51 insertions, 34 deletions

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index bfac1d5ae842..43aeecc4b675 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -127,6 +127,9 @@ static int __init pcie_port_pm_setup(char *str)
 }
 __setup("pcie_port_pm=", pcie_port_pm_setup);
 
+/* Time to wait after a reset for device to become responsive */
+#define PCIE_RESET_READY_POLL_MS 60000
+
 /**
  * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
  * @bus: pointer to PCI bus structure to search
@@ -3969,20 +3972,13 @@ 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_dev_wait(struct pci_dev *dev, char *reset_type, int timeout)
 {
-	int delay = 1, timeout = 60000;
+	int delay = 1;
 	u32 id;
 
 	/*
-	 * Per PCIe r3.1, sec 6.6.2, a device must complete an FLR within
-	 * 100ms, but may silently discard requests while the FLR is in
-	 * progress.  Wait 100ms before trying to access the device.
-	 */
-	msleep(100);
-
-	/*
-	 * After 100ms, the device should not silently discard config
+	 * After reset, the device should not silently discard config
 	 * requests, but it may still indicate that it needs more time by
 	 * responding to them with CRS completions.  The Root Port will
 	 * generally synthesize ~0 data to complete the read (except when
@@ -3996,14 +3992,14 @@ static void pci_flr_wait(struct pci_dev *dev)
 	pci_read_config_dword(dev, PCI_COMMAND, &id);
 	while (id == ~0) {
 		if (delay > timeout) {
-			pci_warn(dev, "not ready %dms after FLR; giving up\n",
-				 100 + delay - 1);
-			return;
+			pci_warn(dev, "not ready %dms after %s; giving up\n",
+				 delay - 1, reset_type);
+			return -ENOTTY;
 		}
 
 		if (delay > 1000)
-			pci_info(dev, "not ready %dms after FLR; waiting\n",
-				 100 + delay - 1);
+			pci_info(dev, "not ready %dms after %s; waiting\n",
+				 delay - 1, reset_type);
 
 		msleep(delay);
 		delay *= 2;
@@ -4011,7 +4007,10 @@ static void pci_flr_wait(struct pci_dev *dev)
 	}
 
 	if (delay > 1000)
-		pci_info(dev, "ready %dms after FLR\n", 100 + delay - 1);
+		pci_info(dev, "ready %dms after %s\n", delay - 1,
+			 reset_type);
+
+	return 0;
 }
 
 /**
@@ -4040,13 +4039,21 @@ 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);
+
+	/*
+	 * Per PCIe r4.0, sec 6.6.2, a device must complete an FLR within
+	 * 100ms, but may silently discard requests while the FLR is in
+	 * progress.  Wait 100ms before trying to access the device.
+	 */
+	msleep(100);
+
+	return pci_dev_wait(dev, "FLR", PCIE_RESET_READY_POLL_MS);
 }
 EXPORT_SYMBOL_GPL(pcie_flr);
 
@@ -4079,8 +4086,16 @@ 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;
+
+	/*
+	 * Per Advanced Capabilities for Conventional PCI ECN, 13 April 2006,
+	 * updated 27 July 2006; a device must complete an FLR within
+	 * 100ms, but may silently discard requests while the FLR is in
+	 * progress.  Wait 100ms before trying to access the device.
+	 */
+	msleep(100);
+
+	return pci_dev_wait(dev, "AF_FLR", PCIE_RESET_READY_POLL_MS);
 }
 
 /**
@@ -4125,7 +4140,7 @@ static int pci_pm_reset(struct pci_dev *dev, int probe)
 	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
 	pci_dev_d3_sleep(dev);
 
-	return 0;
+	return pci_dev_wait(dev, "PM D3->D0", PCIE_RESET_READY_POLL_MS);
 }
 
 void pci_reset_secondary_bus(struct pci_dev *dev)
@@ -4167,9 +4182,11 @@ void __weak pcibios_reset_secondary_bus(struct pci_dev *dev)
  * Use the bridge control register to assert reset on the secondary bus.
  * Devices on the secondary bus are left in power-on state.
  */
-void pci_reset_bridge_secondary_bus(struct pci_dev *dev)
+int pci_reset_bridge_secondary_bus(struct pci_dev *dev)
 {
 	pcibios_reset_secondary_bus(dev);
+
+	return pci_dev_wait(dev, "bus reset", PCIE_RESET_READY_POLL_MS);
 }
 EXPORT_SYMBOL_GPL(pci_reset_bridge_secondary_bus);
 
@@ -4332,8 +4349,9 @@ 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)
@@ -4403,9 +4421,8 @@ int pci_reset_function(struct pci_dev *dev)
 {
 	int rc;
 
-	rc = pci_probe_reset_function(dev);
-	if (rc)
-		return rc;
+	if (!dev->reset_fn)
+		return -ENOTTY;
 
 	pci_dev_lock(dev);
 	pci_dev_save_and_disable(dev);
@@ -4440,9 +4457,8 @@ int pci_reset_function_locked(struct pci_dev *dev)
 {
 	int rc;
 
-	rc = pci_probe_reset_function(dev);
-	if (rc)
-		return rc;
+	if (!dev->reset_fn)
+		return -ENOTTY;
 
 	pci_dev_save_and_disable(dev);
 
@@ -4464,18 +4480,17 @@ int pci_try_reset_function(struct pci_dev *dev)
 {
 	int rc;
 
-	rc = pci_probe_reset_function(dev);
-	if (rc)
-		return rc;
+	if (!dev->reset_fn)
+		return -ENOTTY;
 
 	if (!pci_dev_trylock(dev))
 		return -EAGAIN;
 
 	pci_dev_save_and_disable(dev);
 	rc = __pci_reset_function_locked(dev);
+	pci_dev_restore(dev);
 	pci_dev_unlock(dev);
 
-	pci_dev_restore(dev);
 	return rc;
 }
 EXPORT_SYMBOL_GPL(pci_try_reset_function);
@@ -4683,7 +4698,9 @@ static void pci_slot_restore(struct pci_slot *slot)
 	list_for_each_entry(dev, &slot->bus->devices, bus_list) {
 		if (!dev->slot || dev->slot != slot)
 			continue;
+		pci_dev_lock(dev);
 		pci_dev_restore(dev);
+		pci_dev_unlock(dev);
 		if (dev->subordinate)
 			pci_bus_restore(dev->subordinate);
 	}