* [PATCH v2 1/1] vfio-pci/nvlink2: Allow fallback to ibm,mmio-atsd[0]
@ 2020-03-31 4:12 Sam Bobroff
2020-03-31 5:13 ` Alexey Kardashevskiy
2020-04-01 22:39 ` Alex Williamson
0 siblings, 2 replies; 3+ messages in thread
From: Sam Bobroff @ 2020-03-31 4:12 UTC (permalink / raw)
To: kvm, linuxppc-dev; +Cc: aik
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(-)
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)) {
--
2.22.0.216.g00a2a96fc9
^ permalink raw reply related [flat|nested] 3+ messages in thread* Re: [PATCH v2 1/1] vfio-pci/nvlink2: Allow fallback to ibm,mmio-atsd[0]
2020-03-31 4:12 [PATCH v2 1/1] vfio-pci/nvlink2: Allow fallback to ibm,mmio-atsd[0] Sam Bobroff
@ 2020-03-31 5:13 ` Alexey Kardashevskiy
2020-04-01 22:39 ` Alex Williamson
1 sibling, 0 replies; 3+ messages in thread
From: Alexey Kardashevskiy @ 2020-03-31 5:13 UTC (permalink / raw)
To: Sam Bobroff, kvm, linuxppc-dev
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)) {
>
--
Alexey
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [PATCH v2 1/1] vfio-pci/nvlink2: Allow fallback to ibm,mmio-atsd[0]
2020-03-31 4:12 [PATCH v2 1/1] vfio-pci/nvlink2: Allow fallback to ibm,mmio-atsd[0] Sam Bobroff
2020-03-31 5:13 ` Alexey Kardashevskiy
@ 2020-04-01 22:39 ` Alex Williamson
1 sibling, 0 replies; 3+ messages in thread
From: Alex Williamson @ 2020-04-01 22:39 UTC (permalink / raw)
To: Sam Bobroff; +Cc: aik, linuxppc-dev, kvm
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)) {
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2020-04-01 22:41 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2020-03-31 4:12 [PATCH v2 1/1] vfio-pci/nvlink2: Allow fallback to ibm,mmio-atsd[0] Sam Bobroff
2020-03-31 5:13 ` Alexey Kardashevskiy
2020-04-01 22:39 ` Alex Williamson
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