Subject: Re: [RFC PATCH V3 04/17] PCI: SRIOV: add VF enable/disable hook

From: Gavin Shan <[email-masked]>
Date: Mon, 23 Jun 2014 15:03:10 +1000

On Tue, Jun 10, 2014 at 09:56:26AM +0800, Wei Yang wrote:
>VFs are dynamically created/released when driver enable them. On some
>platforms, like PowerNV, special resources are necessary to enable VFs.
>
>This patch adds two hooks for platform initialization before creating the VFs.
>
>Signed-off-by: Wei Yang <[email-masked]>
>---
> drivers/pci/iov.c |   19 +++++++++++++++++++
> 1 file changed, 19 insertions(+)
>
>diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c
>index 1d21f43..cc87773 100644
>--- a/drivers/pci/iov.c
>+++ b/drivers/pci/iov.c
>@@ -250,6 +250,11 @@ static void sriov_disable_migration(struct pci_dev *dev)
> 	iounmap(iov->mstate);
> }
>
>+int __weak pcibios_sriov_enable(struct pci_dev *pdev, u16 vf_num)
>+{
>+       return 0;
>+}
>+
> static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
> {
> 	int rc;
>@@ -260,6 +265,7 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
> 	struct pci_dev *pdev;
> 	struct pci_sriov *iov = dev->sriov;
> 	int bars = 0;
>+	int retval;
>
> 	if (!nr_virtfn)
> 		return 0;
>@@ -334,6 +340,12 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
> 	if (nr_virtfn < initial)
> 		initial = nr_virtfn;
>
>+	if ((retval = pcibios_sriov_enable(dev, initial))) {
>+		dev_err(&dev->dev, "Failure %d from pcibios_sriov_setup()\n",
>+				retval);

		dev_err(&dev->dev, "Failure %d from pcibios_sriov_enable()\n",
			retval);

>+		return retval;
>+	}
>+
> 	for (i = 0; i < initial; i++) {
> 		rc = virtfn_add(dev, i, 0);
> 		if (rc)
>@@ -368,6 +380,11 @@ failed:
> 	return rc;
> }
>
>+int __weak pcibios_sriov_disable(struct pci_dev *pdev)
>+{
>+       return 0;
>+}
>+
> static void sriov_disable(struct pci_dev *dev)
> {
> 	int i;
>@@ -382,6 +399,8 @@ static void sriov_disable(struct pci_dev *dev)
> 	for (i = 0; i < iov->num_VFs; i++)
> 		virtfn_remove(dev, i, 0);
>
>+	pcibios_sriov_disable(dev);
>+
> 	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);

Thanks,
Gavin