[PATCH v7 39/50] powerpc/powernv: Fundamental reset in pnv_pci_reset_secondary_bus()

[Gavin Shan]

On Thu, Nov 05, 2015 at 12:12:39AM +1100, Gavin Shan wrote:
>In pnv_pci_reset_secondary_bus(), we should issue fundamental
>reset if any one subordinate device of the specified is requesting
                                        ^^^^^^^^^^^^^^

                                        the specified bus

I put the note reminding me to admend the changelog in next revision.

>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 c69b6a1..ab8b93e 100644
>--- a/arch/powerpc/platforms/powernv/eeh-powernv.c
>+++ b/arch/powerpc/platforms/powernv/eeh-powernv.c
>@@ -878,9 +878,28 @@ 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
>