Re: [PATCH v3 1/6] powerpc/powernv: don't enable SRIOV when VF BAR has non 64bit-prefetchable BAR

[Gavin Shan <gwshan@linux.vnet.ibm.com>]

On Thu, Aug 13, 2015 at 10:11:06PM +0800, Wei Yang wrote:
>On PHB_IODA2, we enable SRIOV devices by mapping IOV BAR with M64 BARs. If
>a SRIOV device's IOV BAR is not 64bit-prefetchable, this is not assigned
>from 64bit prefetchable window, which means M64 BAR can't work on it.
>
>This patch makes this explicit.
>
>Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com>

Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>

>---
> arch/powerpc/platforms/powernv/pci-ioda.c |   25 +++++++++----------------
> 1 file changed, 9 insertions(+), 16 deletions(-)
>
>diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
>index 5738d31..9ac324e 100644
>--- a/arch/powerpc/platforms/powernv/pci-ioda.c
>+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
>@@ -908,9 +908,6 @@ static int pnv_pci_vf_resource_shift(struct pci_dev *dev, int offset)
> 		if (!res->flags || !res->parent)
> 			continue;
>
>-		if (!pnv_pci_is_mem_pref_64(res->flags))
>-			continue;
>-
> 		/*
> 		 * The actual IOV BAR range is determined by the start address
> 		 * and the actual size for num_vfs VFs BAR.  This check is to
>@@ -939,9 +936,6 @@ static int pnv_pci_vf_resource_shift(struct pci_dev *dev, int offset)
> 		if (!res->flags || !res->parent)
> 			continue;
>
>-		if (!pnv_pci_is_mem_pref_64(res->flags))
>-			continue;
>-
> 		size = pci_iov_resource_size(dev, i + PCI_IOV_RESOURCES);
> 		res2 = *res;
> 		res->start += size * offset;
>@@ -1221,9 +1215,6 @@ static int pnv_pci_vf_assign_m64(struct pci_dev *pdev, u16 num_vfs)
> 		if (!res->flags || !res->parent)
> 			continue;
>
>-		if (!pnv_pci_is_mem_pref_64(res->flags))
>-			continue;
>-
> 		for (j = 0; j < vf_groups; j++) {
> 			do {
> 				win = find_next_zero_bit(&phb->ioda.m64_bar_alloc,
>@@ -1510,6 +1501,12 @@ int pnv_pci_sriov_enable(struct pci_dev *pdev, u16 num_vfs)
> 	pdn = pci_get_pdn(pdev);
>
> 	if (phb->type == PNV_PHB_IODA2) {
>+		if (!pdn->vfs_expanded) {
>+			dev_info(&pdev->dev, "don't support this SRIOV device"
>+				" with non 64bit-prefetchable IOV BAR\n");
>+			return -ENOSPC;
>+		}
>+
> 		/* Calculate available PE for required VFs */
> 		mutex_lock(&phb->ioda.pe_alloc_mutex);
> 		pdn->offset = bitmap_find_next_zero_area(
>@@ -2774,9 +2771,10 @@ static void pnv_pci_ioda_fixup_iov_resources(struct pci_dev *pdev)
> 		if (!res->flags || res->parent)
> 			continue;
> 		if (!pnv_pci_is_mem_pref_64(res->flags)) {
>-			dev_warn(&pdev->dev, " non M64 VF BAR%d: %pR\n",
>+			dev_warn(&pdev->dev, "Don't support SR-IOV with"
>+					" non M64 VF BAR%d: %pR. \n",
> 				 i, res);
>-			continue;
>+			return;
> 		}
>
> 		size = pci_iov_resource_size(pdev, i + PCI_IOV_RESOURCES);
>@@ -2795,11 +2793,6 @@ static void pnv_pci_ioda_fixup_iov_resources(struct pci_dev *pdev)
> 		res = &pdev->resource[i + PCI_IOV_RESOURCES];
> 		if (!res->flags || res->parent)
> 			continue;
>-		if (!pnv_pci_is_mem_pref_64(res->flags)) {
>-			dev_warn(&pdev->dev, "Skipping expanding VF BAR%d: %pR\n",
>-				 i, res);
>-			continue;
>-		}
>
> 		dev_dbg(&pdev->dev, " Fixing VF BAR%d: %pR to\n", i, res);
> 		size = pci_iov_resource_size(pdev, i + PCI_IOV_RESOURCES);
>-- 
>1.7.9.5
>