On 08/06/2015 02:35 PM, Gavin Shan wrote:
On Wed, Aug 05, 2015 at 09:24:58AM +0800, Wei Yang wrote:
On PHB_IODA2, we enable SRIOV devices by mapping IOV BAR with M64 BARs. If
a SRIOV device's BAR is not 64-bit prefetchable, this is not assigned from
M64 windwo, which means M64 BAR can't work on it.
s/PHB_IODA2/PHB3
No, it is IODA2. OPEL does PHB3-specific bits, the host kernel just uses OPAL.
s/windwo/window
This patch makes this explicit.
Signed-off-by: Wei Yang <weiy...@linux.vnet.ibm.com>
The idea sounds right, but there is one question as below.
---
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..9b41dba 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 M64 VF BAR\n");
+ return -EBUSY;
+ }
+
It would be -ENOSPC since -EBUSY indicates the devices (VFs) are temparily
unavailable. For this case, the VFs are permanently unavailable because of
running out of space to accomodate M64 and non-M64 VF BARs.
The error message could be printed with dev_warn() and it would be precise
as below or something else you prefer:
dev_warn(&pdev->dev, "SRIOV not supported because of non-M64 VF BAR\n");
Both messages are cryptic.
If it is not M64 BAR, then what is it? It is always in one of M64 BARs (in
the worst case - BAR#15?), the difference is if it is segmented or not, no?
/* 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;
- }
When any one IOV BAR on the PF is non-M64, none of the VFs can be enabled.
Will we still allocate/assign M64 or M32 resources for the IOV BARs? If so,
I think it can be avoided.
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
--
Alexey
_______________________________________________
Linuxppc-dev mailing list
Linuxppc-dev@lists.ozlabs.org
https://lists.ozlabs.org/listinfo/linuxppc-dev
