On Mon, Jul 10, 2023 at 01:21:50PM +0530, Ani Sinha wrote:
>
>
> > On 05-Jul-2023, at 7:54 AM, Akihiko Odaki <[email protected]> wrote:
> >
> > The current implementers of ARI are all SR-IOV devices. The ARI next
> > function number field is undefined for VF according to PCI Express Base
> > Specification Revision 5.0 Version 1.0 section 9.3.7.7. The PF should
> > end the linked list formed with the field by specifying 0 according to
> > section 7.8.7.2.
>
> Section 7.8.7.2 ARI Capability Register (Offset 04h), I see only this
>
> Next Function Number - This field indicates the Function Number of the next
> higher numbered Function in the Device, or 00h if there are no higher
> numbered Functions. Function 0 starts this linked list of Functions.
>
> I do not see anything specifically for PF. What am I missing?
This is *only* for PFs. There's separate text explaining that
VFs use NumVFs VFOffset and VFStride.
> >
> > For migration, the field will keep having 1 as its value on the old
> > virt models.
> >
> > Fixes: 2503461691 ("pcie: Add some SR/IOV API documentation in
> > docs/pcie_sriov.txt")
> > Fixes: 44c2c09488 ("hw/nvme: Add support for SR-IOV")
> > Fixes: 3a977deebe ("Intrdocue igb device emulation")
> > Signed-off-by: Akihiko Odaki <[email protected]>
> > ---
> > include/hw/pci/pci.h | 2 ++
> > hw/core/machine.c | 1 +
> > hw/pci/pci.c | 2 ++
> > hw/pci/pcie.c | 2 +-
> > 4 files changed, 6 insertions(+), 1 deletion(-)
> >
> > diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h
> > index e6d0574a29..9c5b5eb206 100644
> > --- a/include/hw/pci/pci.h
> > +++ b/include/hw/pci/pci.h
> > @@ -209,6 +209,8 @@ enum {
> > QEMU_PCIE_CAP_CXL = (1 << QEMU_PCIE_CXL_BITNR),
> > #define QEMU_PCIE_ERR_UNC_MASK_BITNR 11
> > QEMU_PCIE_ERR_UNC_MASK = (1 << QEMU_PCIE_ERR_UNC_MASK_BITNR),
> > +#define QEMU_PCIE_ARI_NEXTFN_1_BITNR 12
> > + QEMU_PCIE_ARI_NEXTFN_1 = (1 << QEMU_PCIE_ARI_NEXTFN_1_BITNR),
> > };
> >
> > typedef struct PCIINTxRoute {
> > diff --git a/hw/core/machine.c b/hw/core/machine.c
> > index 46f8f9a2b0..f0d35c6401 100644
> > --- a/hw/core/machine.c
> > +++ b/hw/core/machine.c
> > @@ -41,6 +41,7 @@
> >
> > GlobalProperty hw_compat_8_0[] = {
> > { "migration", "multifd-flush-after-each-section", "on"},
> > + { TYPE_PCI_DEVICE, "x-pcie-ari-nextfn-1", "on" },
> > };
> > const size_t hw_compat_8_0_len = G_N_ELEMENTS(hw_compat_8_0);
> >
> > diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> > index e2eb4c3b4a..45a9bc0da8 100644
> > --- a/hw/pci/pci.c
> > +++ b/hw/pci/pci.c
> > @@ -82,6 +82,8 @@ static Property pci_props[] = {
> > DEFINE_PROP_UINT32("acpi-index", PCIDevice, acpi_index, 0),
> > DEFINE_PROP_BIT("x-pcie-err-unc-mask", PCIDevice, cap_present,
> > QEMU_PCIE_ERR_UNC_MASK_BITNR, true),
> > + DEFINE_PROP_BIT("x-pcie-ari-nextfn-1", PCIDevice, cap_present,
> > + QEMU_PCIE_ARI_NEXTFN_1_BITNR, false),
> > DEFINE_PROP_END_OF_LIST()
> > };
> >
> > diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c
> > index 9a3f6430e8..cf09e03a10 100644
> > --- a/hw/pci/pcie.c
> > +++ b/hw/pci/pcie.c
> > @@ -1030,7 +1030,7 @@ void pcie_sync_bridge_lnk(PCIDevice *bridge_dev)
> > /* ARI */
> > void pcie_ari_init(PCIDevice *dev, uint16_t offset)
> > {
> > - uint16_t nextfn = 1;
> > + uint16_t nextfn = dev->cap_present & QEMU_PCIE_ARI_NEXTFN_1 ? 1 : 0;
> >
> > pcie_add_capability(dev, PCI_EXT_CAP_ID_ARI, PCI_ARI_VER,
> > offset, PCI_ARI_SIZEOF);
> > --
> > 2.41.0
> >
