Commit f6b7bb84 authored by Jon Derrick's avatar Jon Derrick Committed by Lorenzo Pieralisi
Browse files

PCI: vmd: Offset Client VMD MSI-X vectors 

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.

Link: https://lore.kernel.org/r/20201102222223.92978-1-jonathan.derrick@intel.com


Tested-by: default avatarJian-Hong Pan <jhp@endlessos.org>
Signed-off-by: default avatarJon Derrick <jonathan.derrick@intel.com>
Signed-off-by: default avatarLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
parent f8394f23

drivers/pci/controller/vmd.c

+26 −11
Original line number Diff line number Diff line
@@ -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)
@@ -199,11 +206,11 @@ 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
@@ -213,11 +220,12 @@ static struct vmd_irq_list *vmd_next_irq(struct vmd_dev *vmd, struct msi_desc *d 
	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++;
@@ -550,8 +558,8 @@ static int vmd_alloc_irqs(struct vmd_dev *vmd) 
	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;
@@ -719,6 +727,7 @@ static int vmd_enable_domain(struct vmd_dev *vmd, unsigned long features) 


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 err;
@@ -743,13 +752,16 @@ 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;



	err = vmd_alloc_irqs(vmd);

	if (err)

		return err;



	spin_lock_init(&vmd->cfg_lock);

	pci_set_drvdata(dev, vmd);

	err = vmd_enable_domain(vmd, (unsigned long) id->driver_data);

	err = vmd_enable_domain(vmd, features);

	if (err)

		return err;
@@ -818,13 +830,16 @@ 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);