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 ?
Other than that ready to merge it, please let me know.
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
>
