[PATCH v8 35/45] powerpc/powernv: Fundamental reset in pnv_pci_reset_secondary_bus()

[Gavin Shan]

In pnv_pci_reset_secondary_bus(), we should issue fundamental reset
if any one subordinate device of the specified bus is requesting that.
Otherwise, the device might not come up after the reset.

Signed-off-by: Gavin Shan <gwshan at linux.vnet.ibm.com>
---
 arch/powerpc/platforms/powernv/eeh-powernv.c | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/powernv/eeh-powernv.c b/arch/powerpc/platforms/powernv/eeh-powernv.c
index 593b8dc..c7454ba 100644
--- a/arch/powerpc/platforms/powernv/eeh-powernv.c
+++ b/arch/powerpc/platforms/powernv/eeh-powernv.c
@@ -866,9 +866,28 @@ static int pnv_eeh_bridge_reset(struct pci_dev *dev, int option)
 	return 0;
 }
 
+static int pnv_pci_dev_reset_type(struct pci_dev *pdev, void *data)
+{
+	int *freset = data;
+
+	/*
+	 * Stop the iteration immediately if there has any one
+	 * PCI device requesting fundamental reset.
+	 */
+	*freset |= pdev->needs_freset;
+	return *freset;
+}
+
 void pnv_pci_reset_secondary_bus(struct pci_dev *dev)
 {
-	pnv_eeh_bridge_reset(dev, EEH_RESET_HOT);
+	int option, freset = 0;
+
+	if (dev->subordinate)
+		pci_walk_bus(dev->subordinate,
+			     pnv_pci_dev_reset_type, &freset);
+
+	option = freset ? EEH_RESET_FUNDAMENTAL : EEH_RESET_HOT;
+	pnv_eeh_bridge_reset(dev, option);
 	pnv_eeh_bridge_reset(dev, EEH_RESET_DEACTIVATE);
 }
 
-- 
2.1.0