> From: Zhu, Lingshan <lingshan.zhu@xxxxxxxxx>
> Sent: Tuesday, May 14, 2024 6:58 AM
>
> On 5/13/2024 9:36 PM, Parav Pandit wrote:
> > Hi Lingshan,
> >
> >> From: Zhu Lingshan <lingshan.zhu@xxxxxxxxx>
> >> Sent: Tuesday, May 14, 2024 2:57 AM
> >> To: jasowang@xxxxxxxxxx; mst@xxxxxxxxxx
> >> Cc: virtualization@xxxxxxxxxxxxxxx; Zhu Lingshan
> >> <lingshan.zhu@xxxxxxxxx>
> >> Subject: [PATCH] ifcvf/vDPA: ifcvf drives standard virtio pci devices
> >>
> >> Most of ifcvf code work for standard virtio pci, except for bar4.
> >> This commit makes bar4 only effective for Intel products, thereby
> >> turning ifcvf into a standard virtio pci driver.
> >>
> >> Signed-off-by: Zhu Lingshan <lingshan.zhu@xxxxxxxxx>
> >> ---
> >> drivers/vdpa/Kconfig | 2 +-
> >> drivers/vdpa/ifcvf/ifcvf_base.c | 17 ++++++++++++-----
> >> drivers/vdpa/ifcvf/ifcvf_main.c | 5 ++++-
> >> 3 files changed, 17 insertions(+), 7 deletions(-)
> >>
> >> diff --git a/drivers/vdpa/Kconfig b/drivers/vdpa/Kconfig index
> >> 656c1cb541de..dbf09f35bcef 100644
> >> --- a/drivers/vdpa/Kconfig
> >> +++ b/drivers/vdpa/Kconfig
> >> @@ -44,7 +44,7 @@ config VDPA_USER
> >> in a userspace program.
> >>
> >> config IFCVF
> >> - tristate "Intel IFC VF vDPA driver"
> >> + tristate "Intel IFC VF and standard virtio-pci vDPA driver"
> > The virtio specification limits the subsystem vendor and device id usage for
> informational purposes only.
> > Hence this change/claim here for standard is not good.
> >
> > I don't have objection to have per vendor creativity in the spec, but for that
> let OASIS commit to ratify the spec to use subsystem vendor and device id for
> non-informational purposes.
> > And amend the spec " (for informational purposes by the driver).".
> The spec says:
> The PCI Subsystem Vendor ID and the PCI Subsystem Device ID MAY reflect
> the PCI Vendor and Device ID of the environment (for informational purposes
> by the driver).
>
> I don't see how this change conflicts with the spec.
It does. It is used beyond the _informational_ purposes as described in the previous email.
Let vp_vdpa driver handle the standard device as Michael pointed out.
> >
> >> depends on PCI_MSI
> >> help
> >> This kernel module can drive Intel IFC VF NIC to offload diff
> >> --git a/drivers/vdpa/ifcvf/ifcvf_base.c
> >> b/drivers/vdpa/ifcvf/ifcvf_base.c index
> >> 472daa588a9d..47bc9b11c678 100644
> >> --- a/drivers/vdpa/ifcvf/ifcvf_base.c
> >> +++ b/drivers/vdpa/ifcvf/ifcvf_base.c
> >> @@ -178,7 +178,8 @@ int ifcvf_init_hw(struct ifcvf_hw *hw, struct
> >> pci_dev
> >> *pdev)
> >> hw->vring[i].irq = -EINVAL;
> >> }
> >>
> >> - hw->lm_cfg = hw->base[IFCVF_LM_BAR];
> >> + if (hw->pdev->subsystem_vendor == PCI_VENDOR_ID_INTEL)
> >> + hw->lm_cfg = hw->base[IFCVF_LM_BAR];
> >>
> >> IFCVF_DBG(pdev,
> >> "PCI capability mapping: common cfg: %p, notify base:
> >> %p\n, isr cfg: %p, device cfg: %p, multiplier: %u\n", @@ -330,18
> >> +331,24 @@
> >> u16 ifcvf_get_vq_state(struct ifcvf_hw *hw, u16 qid)
> >> struct ifcvf_lm_cfg __iomem *lm_cfg = hw->lm_cfg;
> >> u16 last_avail_idx;
> >>
> >> - last_avail_idx = vp_ioread16(&lm_cfg->vq_state_region + qid * 2);
> >> + if (lm_cfg) {
> >> + last_avail_idx = vp_ioread16(&lm_cfg->vq_state_region + qid
> >> * 2);
> >> + return last_avail_idx;
> >> + }
> >>
> >> - return last_avail_idx;
> >> + return -EOPNOTSUPP;
> >> }
> >>
> >> int ifcvf_set_vq_state(struct ifcvf_hw *hw, u16 qid, u16 num) {
> >> struct ifcvf_lm_cfg __iomem *lm_cfg = hw->lm_cfg;
> >>
> >> - vp_iowrite16(num, &lm_cfg->vq_state_region + qid * 2);
> >> + if (lm_cfg) {
> >> + vp_iowrite16(num, &lm_cfg->vq_state_region + qid * 2);
> >> + return 0;
> >> + }
> >>
> > This is more than informational and requires OASIS virtio committee to add
> section to indicate per subsystem vendor to allow its modifications.
> This is Intel Specific implementation.
Sure that is fine. So keep it as _intel_ driver.
No need to add "and standard" and things are just fine.
> >
> >> - return 0;
> >> + return -EOPNOTSUPP;
> >> }
> >>
> >> void ifcvf_set_vq_num(struct ifcvf_hw *hw, u16 qid, u32 num) diff
> >> --git a/drivers/vdpa/ifcvf/ifcvf_main.c
> >> b/drivers/vdpa/ifcvf/ifcvf_main.c index
> >> 80d0a0460885..e89fd4d96ff1 100644
> >> --- a/drivers/vdpa/ifcvf/ifcvf_main.c
> >> +++ b/drivers/vdpa/ifcvf/ifcvf_main.c
> >> @@ -1,6 +1,7 @@
> >> // SPDX-License-Identifier: GPL-2.0-only
> >> /*
> >> * Intel IFC VF NIC driver for virtio dataplane offloading
> >> + * This driver also drives standard virtio-pci hardwares
> >> *
> >> * Copyright (C) 2020 Intel Corporation.
> >> *
> >> @@ -880,7 +881,9 @@ static struct pci_device_id ifcvf_pci_ids[] = {
> >> VIRTIO_TRANS_ID_BLOCK,
> >> PCI_VENDOR_ID_INTEL,
> >> VIRTIO_ID_BLOCK) },
> >> -
> >> + /* standard virtio pci devices */
> >> + { PCI_DEVICE(PCI_VENDOR_ID_REDHAT_QUMRANET,
> >> + PCI_ANY_ID) },
> >> { 0 },
> >> };
> >> MODULE_DEVICE_TABLE(pci, ifcvf_pci_ids);
> >> --
> >> 2.43.0
> >>
> >
