Subject: Re: [PATCH v2 1/2] pci: Call pcibios_sriov_enable() before IOV BARs are enabled

From: Gavin Shan <[email-masked]>
Date: Tue, 11 Oct 2016 16:33:53 +1100

On Fri, Sep 30, 2016 at 09:47:49AM +1000, Gavin Shan wrote:
>In current implementation, pcibios_sriov_enable() is used by PPC
>PowerNV platform only. In PowerNV specific pcibios_sriov_enable(),
>PF's IOV BARs might be updated (shifted) by pci_update_resource().
>It means the IOV BARs aren't ready for decoding incoming memory
>address until pcibios_sriov_enable() returns.
>
>This calls pcibios_sriov_enable() earlier before the IOV BARs are
>enabled. As the result, the IOV BARs have been configured correctly
>when they are enabled.
>
>Signed-off-by: Gavin Shan <[email-masked]>
>Tested-by: Carol Soto <[email-masked]>

Bjorn, is there any chance to put those two patches to 4.9? :)

Thanks,
Gavin

>---
> drivers/pci/iov.c | 14 +++++++-------
> 1 file changed, 7 insertions(+), 7 deletions(-)
>
>diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c
>index 2194b44..f1343f0 100644
>--- a/drivers/pci/iov.c
>+++ b/drivers/pci/iov.c
>@@ -303,13 +303,6 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
> 			return rc;
> 	}
>
>-	pci_iov_set_numvfs(dev, nr_virtfn);
>-	iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;
>-	pci_cfg_access_lock(dev);
>-	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
>-	msleep(100);
>-	pci_cfg_access_unlock(dev);
>-
> 	iov->initial_VFs = initial;
> 	if (nr_virtfn < initial)
> 		initial = nr_virtfn;
>@@ -320,6 +313,13 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
> 		goto err_pcibios;
> 	}
>
>+	pci_iov_set_numvfs(dev, nr_virtfn);
>+	iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;
>+	pci_cfg_access_lock(dev);
>+	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
>+	msleep(100);
>+	pci_cfg_access_unlock(dev);
>+
> 	for (i = 0; i < initial; i++) {
> 		rc = pci_iov_add_virtfn(dev, i, 0);
> 		if (rc)
>-- 
>2.1.0
>