| Message ID | 6183bf8ec2dd0433f213e081911ab8fd5cac2dcb.1585627961.git.sbobroff@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2,1/1] vfio-pci/nvlink2: Allow fallback to ibm,mmio-atsd[0] | expand |
On 31/03/2020 15:12, Sam Bobroff wrote: > Older versions of skiboot only provide a single value in the device > tree property "ibm,mmio-atsd", even when multiple Address Translation > Shoot Down (ATSD) registers are present. This prevents NVLink2 devices > (other than the first) from being used with vfio-pci because vfio-pci > expects to be able to assign a dedicated ATSD register to each NVLink2 > device. > > However, ATSD registers can be shared among devices. This change > allows vfio-pci to fall back to sharing the register at index 0 if > necessary. > > Fixes: 7f92891778df ("vfio_pci: Add NVIDIA GV100GL [Tesla V100 SXM2] subdriver") > Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com> Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru> > --- > Patch set v2: > Patch 1/1: vfio-pci/nvlink2: Allow fallback to ibm,mmio-atsd[0] > - Removed unnecessary warning. > - Added Fixes tag. > > Patch set v1: > Patch 1/1: vfio-pci/nvlink2: Allow fallback to ibm,mmio-atsd[0] > > drivers/vfio/pci/vfio_pci_nvlink2.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/drivers/vfio/pci/vfio_pci_nvlink2.c b/drivers/vfio/pci/vfio_pci_nvlink2.c > index f2983f0f84be..ae2af590e501 100644 > --- a/drivers/vfio/pci/vfio_pci_nvlink2.c > +++ b/drivers/vfio/pci/vfio_pci_nvlink2.c > @@ -420,8 +420,14 @@ int vfio_pci_ibm_npu2_init(struct vfio_pci_device *vdev) > > if (of_property_read_u64_index(hose->dn, "ibm,mmio-atsd", nvlink_index, > &mmio_atsd)) { > - dev_warn(&vdev->pdev->dev, "No available ATSD found\n"); > - mmio_atsd = 0; > + if (of_property_read_u64_index(hose->dn, "ibm,mmio-atsd", 0, > + &mmio_atsd)) { > + dev_warn(&vdev->pdev->dev, "No available ATSD found\n"); > + mmio_atsd = 0; > + } else { > + dev_warn(&vdev->pdev->dev, > + "Using fallback ibm,mmio-atsd[0] for ATSD.\n"); > + } > } > > if (of_property_read_u64(npu_node, "ibm,device-tgt-addr", &tgt)) { >
On Tue, 31 Mar 2020 15:12:46 +1100 Sam Bobroff <sbobroff@linux.ibm.com> wrote: > Older versions of skiboot only provide a single value in the device > tree property "ibm,mmio-atsd", even when multiple Address Translation > Shoot Down (ATSD) registers are present. This prevents NVLink2 devices > (other than the first) from being used with vfio-pci because vfio-pci > expects to be able to assign a dedicated ATSD register to each NVLink2 > device. > > However, ATSD registers can be shared among devices. This change > allows vfio-pci to fall back to sharing the register at index 0 if > necessary. > > Fixes: 7f92891778df ("vfio_pci: Add NVIDIA GV100GL [Tesla V100 SXM2] subdriver") > Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com> > --- > Patch set v2: > Patch 1/1: vfio-pci/nvlink2: Allow fallback to ibm,mmio-atsd[0] > - Removed unnecessary warning. > - Added Fixes tag. > > Patch set v1: > Patch 1/1: vfio-pci/nvlink2: Allow fallback to ibm,mmio-atsd[0] > > drivers/vfio/pci/vfio_pci_nvlink2.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) Applied to vfio next branch for v5.7 with Alexey's review. Thanks, Alex > diff --git a/drivers/vfio/pci/vfio_pci_nvlink2.c b/drivers/vfio/pci/vfio_pci_nvlink2.c > index f2983f0f84be..ae2af590e501 100644 > --- a/drivers/vfio/pci/vfio_pci_nvlink2.c > +++ b/drivers/vfio/pci/vfio_pci_nvlink2.c > @@ -420,8 +420,14 @@ int vfio_pci_ibm_npu2_init(struct vfio_pci_device *vdev) > > if (of_property_read_u64_index(hose->dn, "ibm,mmio-atsd", nvlink_index, > &mmio_atsd)) { > - dev_warn(&vdev->pdev->dev, "No available ATSD found\n"); > - mmio_atsd = 0; > + if (of_property_read_u64_index(hose->dn, "ibm,mmio-atsd", 0, > + &mmio_atsd)) { > + dev_warn(&vdev->pdev->dev, "No available ATSD found\n"); > + mmio_atsd = 0; > + } else { > + dev_warn(&vdev->pdev->dev, > + "Using fallback ibm,mmio-atsd[0] for ATSD.\n"); > + } > } > > if (of_property_read_u64(npu_node, "ibm,device-tgt-addr", &tgt)) {
diff --git a/drivers/vfio/pci/vfio_pci_nvlink2.c b/drivers/vfio/pci/vfio_pci_nvlink2.c index f2983f0f84be..ae2af590e501 100644 --- a/drivers/vfio/pci/vfio_pci_nvlink2.c +++ b/drivers/vfio/pci/vfio_pci_nvlink2.c @@ -420,8 +420,14 @@ int vfio_pci_ibm_npu2_init(struct vfio_pci_device *vdev) if (of_property_read_u64_index(hose->dn, "ibm,mmio-atsd", nvlink_index, &mmio_atsd)) { - dev_warn(&vdev->pdev->dev, "No available ATSD found\n"); - mmio_atsd = 0; + if (of_property_read_u64_index(hose->dn, "ibm,mmio-atsd", 0, + &mmio_atsd)) { + dev_warn(&vdev->pdev->dev, "No available ATSD found\n"); + mmio_atsd = 0; + } else { + dev_warn(&vdev->pdev->dev, + "Using fallback ibm,mmio-atsd[0] for ATSD.\n"); + } } if (of_property_read_u64(npu_node, "ibm,device-tgt-addr", &tgt)) {
Older versions of skiboot only provide a single value in the device tree property "ibm,mmio-atsd", even when multiple Address Translation Shoot Down (ATSD) registers are present. This prevents NVLink2 devices (other than the first) from being used with vfio-pci because vfio-pci expects to be able to assign a dedicated ATSD register to each NVLink2 device. However, ATSD registers can be shared among devices. This change allows vfio-pci to fall back to sharing the register at index 0 if necessary. Fixes: 7f92891778df ("vfio_pci: Add NVIDIA GV100GL [Tesla V100 SXM2] subdriver") Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com> --- Patch set v2: Patch 1/1: vfio-pci/nvlink2: Allow fallback to ibm,mmio-atsd[0] - Removed unnecessary warning. - Added Fixes tag. Patch set v1: Patch 1/1: vfio-pci/nvlink2: Allow fallback to ibm,mmio-atsd[0] drivers/vfio/pci/vfio_pci_nvlink2.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)