| Message ID | 20200914173255.5481-1-jonathan.derrick@intel.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | [v2] PCI: vmd: Offset Client VMD MSI/X vectors | expand |
On Mon, Sep 14, 2020 at 01:32:55PM -0400, Jon Derrick wrote: > Client VMD platforms have a software-triggered MSI/X vector 0 that will > not forward hardware-remapped MSI/X vectors from the sub-device domain. > This causes an issue with VMD platforms that use AHCI behind VMD and > have a single MSI/X vector mapping to vector 0. Add an MSI/X vector > offset for these platforms. > > Signed-off-by: Jon Derrick <jonathan.derrick@intel.com> > --- > drivers/pci/controller/vmd.c | 35 +++++++++++++++++++++++++---------- > 1 file changed, 25 insertions(+), 10 deletions(-) > > diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c > index f69ef8c89f72..f8195bad79d1 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/X 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) This condition needs account for the vector offset, right? if (vmd->msix_count == 1 + vmd->first_vec)) > - return &vmd->irqs[0]; > + return &vmd->irqs[vmd->first_vec];
Hi Jon, This refers to "MSI/X" (subject, commit log of this patch, as well as other recent patches). I don't know if that means what the spec calls "MSI-X", or if you mean something like "MSI or MSI-X" (there is one reference in vmd.c to "MSI/MSI-X"). I'd sort of rather avoid adding "MSI/X" to the PCI lexicon because of this ambiguity. If it's not important to the meaning or if it's clear from context that "MSI" is a generic term for "either MSI or MSI-X", I'm ok with using that. Bjorn On Mon, Sep 14, 2020 at 01:32:55PM -0400, Jon Derrick wrote: > Client VMD platforms have a software-triggered MSI/X vector 0 that will > not forward hardware-remapped MSI/X vectors from the sub-device domain. > This causes an issue with VMD platforms that use AHCI behind VMD and > have a single MSI/X vector mapping to vector 0. Add an MSI/X vector > offset for these platforms. > > Signed-off-by: Jon Derrick <jonathan.derrick@intel.com> > --- > drivers/pci/controller/vmd.c | 35 +++++++++++++++++++++++++---------- > 1 file changed, 25 insertions(+), 10 deletions(-) > > diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c > index f69ef8c89f72..f8195bad79d1 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/X remapping > + */ > + VMD_FEAT_OFFSET_FIRST_VECTOR = (1 << 3), ...
On Tue, 2020-09-15 at 03:42 +0900, Keith Busch wrote: > On Mon, Sep 14, 2020 at 01:32:55PM -0400, Jon Derrick wrote: > > Client VMD platforms have a software-triggered MSI/X vector 0 that will > > not forward hardware-remapped MSI/X vectors from the sub-device domain. > > This causes an issue with VMD platforms that use AHCI behind VMD and > > have a single MSI/X vector mapping to vector 0. Add an MSI/X vector > > offset for these platforms. > > > > Signed-off-by: Jon Derrick <jonathan.derrick@intel.com> > > --- > > drivers/pci/controller/vmd.c | 35 +++++++++++++++++++++++++---------- > > 1 file changed, 25 insertions(+), 10 deletions(-) > > > > diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c > > index f69ef8c89f72..f8195bad79d1 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/X 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) > > This condition needs account for the vector offset, right? > > if (vmd->msix_count == 1 + vmd->first_vec)) Looks like it, yes Thank you > > > - return &vmd->irqs[0]; > > + return &vmd->irqs[vmd->first_vec];
diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c index f69ef8c89f72..f8195bad79d1 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/X 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]; + 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 * "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);
Client VMD platforms have a software-triggered MSI/X vector 0 that will not forward hardware-remapped MSI/X vectors from the sub-device domain. This causes an issue with VMD platforms that use AHCI behind VMD and have a single MSI/X vector mapping to vector 0. Add an MSI/X vector offset for these platforms. Signed-off-by: Jon Derrick <jonathan.derrick@intel.com> --- drivers/pci/controller/vmd.c | 35 +++++++++++++++++++++++++---------- 1 file changed, 25 insertions(+), 10 deletions(-)