[5/5] PCI: add device wait after slot and bus reset

Commit Message

Sinan Kaya Sept. 24, 2017, 12:16 a.m. UTC

Rev 3.1 Sec 2.3.1 Request Handling Rules indicates that a device can issue
CRS following secondary bus reset. Handle device presence gracefully.

Signed-off-by: Sinan Kaya <[e-mail]>
---
 drivers/pci/pci.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

Comments

Sinan Kaya Sept. 24, 2017, 12:20 a.m. UTC | #1

On 9/23/2017 8:16 PM, Sinan Kaya wrote:
> @@ -4056,7 +4056,7 @@ static int pci_parent_bus_reset(struct pci_dev *dev, int probe)
>  
>  	pci_reset_bridge_secondary_bus(dev->bus->self);
>  
> -	return 0;
> +	return pci_dev_wait(dev, "bus reset", 1000, 60000);
>  }

This doesn't solve the warm reset message getting broadcasted. I wanted to get
feedback on the direction first with this version.

Patch

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 074adf9..7131aab 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -4056,7 +4056,7 @@  static int pci_parent_bus_reset(struct pci_dev *dev, int probe)
 
 	pci_reset_bridge_secondary_bus(dev->bus->self);
 
-	return 0;
+	return pci_dev_wait(dev, "bus reset", 1000, 60000);
 }
 
 static int pci_reset_hotplug_slot(struct hotplug_slot *hotplug, int probe)
@@ -4077,6 +4077,7 @@  static int pci_reset_hotplug_slot(struct hotplug_slot *hotplug, int probe)
 static int pci_dev_reset_slot_function(struct pci_dev *dev, int probe)
 {
 	struct pci_dev *pdev;
+	int rc;
 
 	if (dev->subordinate || !dev->slot ||
 	    dev->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET)
@@ -4086,7 +4087,11 @@  static int pci_dev_reset_slot_function(struct pci_dev *dev, int probe)
 		if (pdev != dev && pdev->slot == dev->slot)
 			return -ENOTTY;
 
-	return pci_reset_hotplug_slot(dev->slot->hotplug, probe);
+	rc = pci_reset_hotplug_slot(dev->slot->hotplug, probe);
+	if (!rc && !probe)
+		rc = pci_dev_wait(dev, "slot reset", 1000, 60000);
+
+	return rc;
 }
 
 static void pci_dev_lock(struct pci_dev *dev)