On Mon, 2020-10-05 at 12:23 +0100, Lorenzo Pieralisi wrote:
> On Mon, Sep 14, 2020 at 03:01:28PM -0400, Jon Derrick wrote:
> > Client VMD platforms have a software-triggered MSI-X vector 0 that will
> > not forward hardware-remapped MSI from the sub-device domain. This
> > causes an issue with VMD platforms that use AHCI behind VMD and have a
> > single MSI-X vector remapped to VMD vector 0. Add a VMD MSI-X vector
> > offset for these platforms.
> >
> > Signed-off-by: Jon Derrick <jonathan.derrick@xxxxxxxxx>
> > ---
> > v3: Commit MSI-X cleanup
> > vmd_next_irq check fix per Keith
> >
> > drivers/pci/controller/vmd.c | 37 +++++++++++++++++++++++++-----------
> > 1 file changed, 26 insertions(+), 11 deletions(-)
> >
> > diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c
> > index f69ef8c89f72..10c0d20190e0 100644
> > --- a/drivers/pci/controller/vmd.c
> > +++ b/drivers/pci/controller/vmd.c
> > @@ -53,6 +53,12 @@ enum vmd_features {
> > * vendor-specific capability space
> > */
> > VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP = (1 << 2),
> > +
> > + /*
> > + * Device may use MSI-X vector 0 for software triggering and will not
> > + * be used for MSI remapping
> > + */
> > + VMD_FEAT_OFFSET_FIRST_VECTOR = (1 << 3),
> > };
> >
> > /*
> > @@ -104,6 +110,7 @@ struct vmd_dev {
> > struct irq_domain *irq_domain;
> > struct pci_bus *bus;
> > u8 busn_start;
> > + u8 first_vec;
> > };
> >
> > static inline struct vmd_dev *vmd_from_bus(struct pci_bus *bus)
> > @@ -199,25 +206,26 @@ static irq_hw_number_t vmd_get_hwirq(struct msi_domain_info *info,
> > */
> > static struct vmd_irq_list *vmd_next_irq(struct vmd_dev *vmd, struct msi_desc *desc)
> > {
> > - int i, best = 1;
> > unsigned long flags;
> > + int i, best;
> >
> > - if (vmd->msix_count == 1)
> > - return &vmd->irqs[0];
> > + if (vmd->msix_count == 1 + vmd->first_vec)
> > + return &vmd->irqs[vmd->first_vec];
> >
> > /*
> > - * White list for fast-interrupt handlers. All others will share the
> > + * Allow list for fast-interrupt handlers. All others will share the
>
> Is this comment change related to this patch logical change ?
It's for following conduct standards but not related
>
> Other than that ready to merge it, please let me know.
>
This will be necessary as the 'remapping disable' set had conflicts
with X86 MSI cleanup.
It's ready to merge if the remapping set is dropped.
> Thanks,
> Lorenzo
>
> > * "slow" interrupt vector.
> > */
> > switch (msi_desc_to_pci_dev(desc)->class) {
> > case PCI_CLASS_STORAGE_EXPRESS:
> > break;
> > default:
> > - return &vmd->irqs[0];
> > + return &vmd->irqs[vmd->first_vec];
> > }
> >
> > raw_spin_lock_irqsave(&list_lock, flags);
> > - for (i = 1; i < vmd->msix_count; i++)
> > + best = vmd->first_vec + 1;
> > + for (i = best; i < vmd->msix_count; i++)
> > if (vmd->irqs[i].count < vmd->irqs[best].count)
> > best = i;
> > vmd->irqs[best].count++;
> > @@ -629,6 +637,7 @@ static irqreturn_t vmd_irq(int irq, void *data)
> >
> > static int vmd_probe(struct pci_dev *dev, const struct pci_device_id *id)
> > {
> > + unsigned long features = (unsigned long) id->driver_data;
> > struct vmd_dev *vmd;
> > int i, err;
> >
> > @@ -653,12 +662,15 @@ static int vmd_probe(struct pci_dev *dev, const struct pci_device_id *id)
> > dma_set_mask_and_coherent(&dev->dev, DMA_BIT_MASK(32)))
> > return -ENODEV;
> >
> > + if (features & VMD_FEAT_OFFSET_FIRST_VECTOR)
> > + vmd->first_vec = 1;
> > +
> > vmd->msix_count = pci_msix_vec_count(dev);
> > if (vmd->msix_count < 0)
> > return -ENODEV;
> >
> > - vmd->msix_count = pci_alloc_irq_vectors(dev, 1, vmd->msix_count,
> > - PCI_IRQ_MSIX);
> > + vmd->msix_count = pci_alloc_irq_vectors(dev, vmd->first_vec + 1,
> > + vmd->msix_count, PCI_IRQ_MSIX);
> > if (vmd->msix_count < 0)
> > return vmd->msix_count;
> >
> > @@ -755,13 +767,16 @@ static const struct pci_device_id vmd_ids[] = {
> > VMD_FEAT_HAS_BUS_RESTRICTIONS,},
> > {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x467f),
> > .driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP |
> > - VMD_FEAT_HAS_BUS_RESTRICTIONS,},
> > + VMD_FEAT_HAS_BUS_RESTRICTIONS |
> > + VMD_FEAT_OFFSET_FIRST_VECTOR,},
> > {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x4c3d),
> > .driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP |
> > - VMD_FEAT_HAS_BUS_RESTRICTIONS,},
> > + VMD_FEAT_HAS_BUS_RESTRICTIONS |
> > + VMD_FEAT_OFFSET_FIRST_VECTOR,},
> > {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_VMD_9A0B),
> > .driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP |
> > - VMD_FEAT_HAS_BUS_RESTRICTIONS,},
> > + VMD_FEAT_HAS_BUS_RESTRICTIONS |
> > + VMD_FEAT_OFFSET_FIRST_VECTOR,},
> > {0,}
> > };
> > MODULE_DEVICE_TABLE(pci, vmd_ids);
> > --
> > 2.18.1
> >
