diff options
Diffstat (limited to 'kernel/arch/x86/pci/xen.c')
| -rw-r--r-- | kernel/arch/x86/pci/xen.c | 581 |
1 files changed, 581 insertions, 0 deletions
diff --git a/kernel/arch/x86/pci/xen.c b/kernel/arch/x86/pci/xen.c new file mode 100644 index 000000000..d22f4b5bb --- /dev/null +++ b/kernel/arch/x86/pci/xen.c @@ -0,0 +1,581 @@ +/* + * Xen PCI - handle PCI (INTx) and MSI infrastructure calls for PV, HVM and + * initial domain support. We also handle the DSDT _PRT callbacks for GSI's + * used in HVM and initial domain mode (PV does not parse ACPI, so it has no + * concept of GSIs). Under PV we hook under the pnbbios API for IRQs and + * 0xcf8 PCI configuration read/write. + * + * Author: Ryan Wilson <hap9@epoch.ncsc.mil> + * Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> + * Stefano Stabellini <stefano.stabellini@eu.citrix.com> + */ +#include <linux/module.h> +#include <linux/init.h> +#include <linux/pci.h> +#include <linux/acpi.h> + +#include <linux/io.h> +#include <asm/io_apic.h> +#include <asm/pci_x86.h> + +#include <asm/xen/hypervisor.h> + +#include <xen/features.h> +#include <xen/events.h> +#include <asm/xen/pci.h> +#include <asm/xen/cpuid.h> +#include <asm/apic.h> +#include <asm/i8259.h> + +static int xen_pcifront_enable_irq(struct pci_dev *dev) +{ + int rc; + int share = 1; + int pirq; + u8 gsi; + + rc = pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &gsi); + if (rc < 0) { + dev_warn(&dev->dev, "Xen PCI: failed to read interrupt line: %d\n", + rc); + return rc; + } + /* In PV DomU the Xen PCI backend puts the PIRQ in the interrupt line.*/ + pirq = gsi; + + if (gsi < nr_legacy_irqs()) + share = 0; + + rc = xen_bind_pirq_gsi_to_irq(gsi, pirq, share, "pcifront"); + if (rc < 0) { + dev_warn(&dev->dev, "Xen PCI: failed to bind GSI%d (PIRQ%d) to IRQ: %d\n", + gsi, pirq, rc); + return rc; + } + + dev->irq = rc; + dev_info(&dev->dev, "Xen PCI mapped GSI%d to IRQ%d\n", gsi, dev->irq); + return 0; +} + +#ifdef CONFIG_ACPI +static int xen_register_pirq(u32 gsi, int gsi_override, int triggering, + bool set_pirq) +{ + int rc, pirq = -1, irq = -1; + struct physdev_map_pirq map_irq; + int shareable = 0; + char *name; + + irq = xen_irq_from_gsi(gsi); + if (irq > 0) + return irq; + + if (set_pirq) + pirq = gsi; + + map_irq.domid = DOMID_SELF; + map_irq.type = MAP_PIRQ_TYPE_GSI; + map_irq.index = gsi; + map_irq.pirq = pirq; + + rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq); + if (rc) { + printk(KERN_WARNING "xen map irq failed %d\n", rc); + return -1; + } + + if (triggering == ACPI_EDGE_SENSITIVE) { + shareable = 0; + name = "ioapic-edge"; + } else { + shareable = 1; + name = "ioapic-level"; + } + + if (gsi_override >= 0) + gsi = gsi_override; + + irq = xen_bind_pirq_gsi_to_irq(gsi, map_irq.pirq, shareable, name); + if (irq < 0) + goto out; + + printk(KERN_DEBUG "xen: --> pirq=%d -> irq=%d (gsi=%d)\n", map_irq.pirq, irq, gsi); +out: + return irq; +} + +static int acpi_register_gsi_xen_hvm(struct device *dev, u32 gsi, + int trigger, int polarity) +{ + if (!xen_hvm_domain()) + return -1; + + return xen_register_pirq(gsi, -1 /* no GSI override */, trigger, + false /* no mapping of GSI to PIRQ */); +} + +#ifdef CONFIG_XEN_DOM0 +static int xen_register_gsi(u32 gsi, int gsi_override, int triggering, int polarity) +{ + int rc, irq; + struct physdev_setup_gsi setup_gsi; + + if (!xen_pv_domain()) + return -1; + + printk(KERN_DEBUG "xen: registering gsi %u triggering %d polarity %d\n", + gsi, triggering, polarity); + + irq = xen_register_pirq(gsi, gsi_override, triggering, true); + + setup_gsi.gsi = gsi; + setup_gsi.triggering = (triggering == ACPI_EDGE_SENSITIVE ? 0 : 1); + setup_gsi.polarity = (polarity == ACPI_ACTIVE_HIGH ? 0 : 1); + + rc = HYPERVISOR_physdev_op(PHYSDEVOP_setup_gsi, &setup_gsi); + if (rc == -EEXIST) + printk(KERN_INFO "Already setup the GSI :%d\n", gsi); + else if (rc) { + printk(KERN_ERR "Failed to setup GSI :%d, err_code:%d\n", + gsi, rc); + } + + return irq; +} + +static int acpi_register_gsi_xen(struct device *dev, u32 gsi, + int trigger, int polarity) +{ + return xen_register_gsi(gsi, -1 /* no GSI override */, trigger, polarity); +} +#endif +#endif + +#if defined(CONFIG_PCI_MSI) +#include <linux/msi.h> +#include <asm/msidef.h> + +struct xen_pci_frontend_ops *xen_pci_frontend; +EXPORT_SYMBOL_GPL(xen_pci_frontend); + +static int xen_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) +{ + int irq, ret, i; + struct msi_desc *msidesc; + int *v; + + if (type == PCI_CAP_ID_MSI && nvec > 1) + return 1; + + v = kzalloc(sizeof(int) * max(1, nvec), GFP_KERNEL); + if (!v) + return -ENOMEM; + + if (type == PCI_CAP_ID_MSIX) + ret = xen_pci_frontend_enable_msix(dev, v, nvec); + else + ret = xen_pci_frontend_enable_msi(dev, v); + if (ret) + goto error; + i = 0; + list_for_each_entry(msidesc, &dev->msi_list, list) { + irq = xen_bind_pirq_msi_to_irq(dev, msidesc, v[i], + (type == PCI_CAP_ID_MSI) ? nvec : 1, + (type == PCI_CAP_ID_MSIX) ? + "pcifront-msi-x" : + "pcifront-msi", + DOMID_SELF); + if (irq < 0) { + ret = irq; + goto free; + } + i++; + } + kfree(v); + return 0; + +error: + dev_err(&dev->dev, "Xen PCI frontend has not registered MSI/MSI-X support!\n"); +free: + kfree(v); + return ret; +} + +#define XEN_PIRQ_MSI_DATA (MSI_DATA_TRIGGER_EDGE | \ + MSI_DATA_LEVEL_ASSERT | (3 << 8) | MSI_DATA_VECTOR(0)) + +static void xen_msi_compose_msg(struct pci_dev *pdev, unsigned int pirq, + struct msi_msg *msg) +{ + /* We set vector == 0 to tell the hypervisor we don't care about it, + * but we want a pirq setup instead. + * We use the dest_id field to pass the pirq that we want. */ + msg->address_hi = MSI_ADDR_BASE_HI | MSI_ADDR_EXT_DEST_ID(pirq); + msg->address_lo = + MSI_ADDR_BASE_LO | + MSI_ADDR_DEST_MODE_PHYSICAL | + MSI_ADDR_REDIRECTION_CPU | + MSI_ADDR_DEST_ID(pirq); + + msg->data = XEN_PIRQ_MSI_DATA; +} + +static int xen_hvm_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) +{ + int irq, pirq; + struct msi_desc *msidesc; + struct msi_msg msg; + + if (type == PCI_CAP_ID_MSI && nvec > 1) + return 1; + + list_for_each_entry(msidesc, &dev->msi_list, list) { + __pci_read_msi_msg(msidesc, &msg); + pirq = MSI_ADDR_EXT_DEST_ID(msg.address_hi) | + ((msg.address_lo >> MSI_ADDR_DEST_ID_SHIFT) & 0xff); + if (msg.data != XEN_PIRQ_MSI_DATA || + xen_irq_from_pirq(pirq) < 0) { + pirq = xen_allocate_pirq_msi(dev, msidesc); + if (pirq < 0) { + irq = -ENODEV; + goto error; + } + xen_msi_compose_msg(dev, pirq, &msg); + __pci_write_msi_msg(msidesc, &msg); + dev_dbg(&dev->dev, "xen: msi bound to pirq=%d\n", pirq); + } else { + dev_dbg(&dev->dev, + "xen: msi already bound to pirq=%d\n", pirq); + } + irq = xen_bind_pirq_msi_to_irq(dev, msidesc, pirq, + (type == PCI_CAP_ID_MSI) ? nvec : 1, + (type == PCI_CAP_ID_MSIX) ? + "msi-x" : "msi", + DOMID_SELF); + if (irq < 0) + goto error; + dev_dbg(&dev->dev, + "xen: msi --> pirq=%d --> irq=%d\n", pirq, irq); + } + return 0; + +error: + dev_err(&dev->dev, + "Xen PCI frontend has not registered MSI/MSI-X support!\n"); + return irq; +} + +#ifdef CONFIG_XEN_DOM0 +static bool __read_mostly pci_seg_supported = true; + +static int xen_initdom_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) +{ + int ret = 0; + struct msi_desc *msidesc; + + list_for_each_entry(msidesc, &dev->msi_list, list) { + struct physdev_map_pirq map_irq; + domid_t domid; + + domid = ret = xen_find_device_domain_owner(dev); + /* N.B. Casting int's -ENODEV to uint16_t results in 0xFFED, + * hence check ret value for < 0. */ + if (ret < 0) + domid = DOMID_SELF; + + memset(&map_irq, 0, sizeof(map_irq)); + map_irq.domid = domid; + map_irq.type = MAP_PIRQ_TYPE_MSI_SEG; + map_irq.index = -1; + map_irq.pirq = -1; + map_irq.bus = dev->bus->number | + (pci_domain_nr(dev->bus) << 16); + map_irq.devfn = dev->devfn; + + if (type == PCI_CAP_ID_MSI && nvec > 1) { + map_irq.type = MAP_PIRQ_TYPE_MULTI_MSI; + map_irq.entry_nr = nvec; + } else if (type == PCI_CAP_ID_MSIX) { + int pos; + unsigned long flags; + u32 table_offset, bir; + + pos = dev->msix_cap; + pci_read_config_dword(dev, pos + PCI_MSIX_TABLE, + &table_offset); + bir = (u8)(table_offset & PCI_MSIX_TABLE_BIR); + flags = pci_resource_flags(dev, bir); + if (!flags || (flags & IORESOURCE_UNSET)) + return -EINVAL; + + map_irq.table_base = pci_resource_start(dev, bir); + map_irq.entry_nr = msidesc->msi_attrib.entry_nr; + } + + ret = -EINVAL; + if (pci_seg_supported) + ret = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, + &map_irq); + if (type == PCI_CAP_ID_MSI && nvec > 1 && ret) { + /* + * If MAP_PIRQ_TYPE_MULTI_MSI is not available + * there's nothing else we can do in this case. + * Just set ret > 0 so driver can retry with + * single MSI. + */ + ret = 1; + goto out; + } + if (ret == -EINVAL && !pci_domain_nr(dev->bus)) { + map_irq.type = MAP_PIRQ_TYPE_MSI; + map_irq.index = -1; + map_irq.pirq = -1; + map_irq.bus = dev->bus->number; + ret = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, + &map_irq); + if (ret != -EINVAL) + pci_seg_supported = false; + } + if (ret) { + dev_warn(&dev->dev, "xen map irq failed %d for %d domain\n", + ret, domid); + goto out; + } + + ret = xen_bind_pirq_msi_to_irq(dev, msidesc, map_irq.pirq, + (type == PCI_CAP_ID_MSI) ? nvec : 1, + (type == PCI_CAP_ID_MSIX) ? "msi-x" : "msi", + domid); + if (ret < 0) + goto out; + } + ret = 0; +out: + return ret; +} + +static void xen_initdom_restore_msi_irqs(struct pci_dev *dev) +{ + int ret = 0; + + if (pci_seg_supported) { + struct physdev_pci_device restore_ext; + + restore_ext.seg = pci_domain_nr(dev->bus); + restore_ext.bus = dev->bus->number; + restore_ext.devfn = dev->devfn; + ret = HYPERVISOR_physdev_op(PHYSDEVOP_restore_msi_ext, + &restore_ext); + if (ret == -ENOSYS) + pci_seg_supported = false; + WARN(ret && ret != -ENOSYS, "restore_msi_ext -> %d\n", ret); + } + if (!pci_seg_supported) { + struct physdev_restore_msi restore; + + restore.bus = dev->bus->number; + restore.devfn = dev->devfn; + ret = HYPERVISOR_physdev_op(PHYSDEVOP_restore_msi, &restore); + WARN(ret && ret != -ENOSYS, "restore_msi -> %d\n", ret); + } +} +#endif + +static void xen_teardown_msi_irqs(struct pci_dev *dev) +{ + struct msi_desc *msidesc; + + msidesc = list_entry(dev->msi_list.next, struct msi_desc, list); + if (msidesc->msi_attrib.is_msix) + xen_pci_frontend_disable_msix(dev); + else + xen_pci_frontend_disable_msi(dev); + + /* Free the IRQ's and the msidesc using the generic code. */ + default_teardown_msi_irqs(dev); +} + +static void xen_teardown_msi_irq(unsigned int irq) +{ + xen_destroy_irq(irq); +} + +#endif + +int __init pci_xen_init(void) +{ + if (!xen_pv_domain() || xen_initial_domain()) + return -ENODEV; + + printk(KERN_INFO "PCI: setting up Xen PCI frontend stub\n"); + + pcibios_set_cache_line_size(); + + pcibios_enable_irq = xen_pcifront_enable_irq; + pcibios_disable_irq = NULL; + +#ifdef CONFIG_ACPI + /* Keep ACPI out of the picture */ + acpi_noirq = 1; +#endif + +#ifdef CONFIG_PCI_MSI + x86_msi.setup_msi_irqs = xen_setup_msi_irqs; + x86_msi.teardown_msi_irq = xen_teardown_msi_irq; + x86_msi.teardown_msi_irqs = xen_teardown_msi_irqs; + pci_msi_ignore_mask = 1; +#endif + return 0; +} + +#ifdef CONFIG_PCI_MSI +void __init xen_msi_init(void) +{ + if (!disable_apic) { + /* + * If hardware supports (x2)APIC virtualization (as indicated + * by hypervisor's leaf 4) then we don't need to use pirqs/ + * event channels for MSI handling and instead use regular + * APIC processing + */ + uint32_t eax = cpuid_eax(xen_cpuid_base() + 4); + + if (((eax & XEN_HVM_CPUID_X2APIC_VIRT) && x2apic_mode) || + ((eax & XEN_HVM_CPUID_APIC_ACCESS_VIRT) && cpu_has_apic)) + return; + } + + x86_msi.setup_msi_irqs = xen_hvm_setup_msi_irqs; + x86_msi.teardown_msi_irq = xen_teardown_msi_irq; +} +#endif + +int __init pci_xen_hvm_init(void) +{ + if (!xen_have_vector_callback || !xen_feature(XENFEAT_hvm_pirqs)) + return 0; + +#ifdef CONFIG_ACPI + /* + * We don't want to change the actual ACPI delivery model, + * just how GSIs get registered. + */ + __acpi_register_gsi = acpi_register_gsi_xen_hvm; + __acpi_unregister_gsi = NULL; +#endif + +#ifdef CONFIG_PCI_MSI + /* + * We need to wait until after x2apic is initialized + * before we can set MSI IRQ ops. + */ + x86_platform.apic_post_init = xen_msi_init; +#endif + return 0; +} + +#ifdef CONFIG_XEN_DOM0 +int __init pci_xen_initial_domain(void) +{ + int irq; + +#ifdef CONFIG_PCI_MSI + x86_msi.setup_msi_irqs = xen_initdom_setup_msi_irqs; + x86_msi.teardown_msi_irq = xen_teardown_msi_irq; + x86_msi.restore_msi_irqs = xen_initdom_restore_msi_irqs; + pci_msi_ignore_mask = 1; +#endif + __acpi_register_gsi = acpi_register_gsi_xen; + __acpi_unregister_gsi = NULL; + /* Pre-allocate legacy irqs */ + for (irq = 0; irq < nr_legacy_irqs(); irq++) { + int trigger, polarity; + + if (acpi_get_override_irq(irq, &trigger, &polarity) == -1) + continue; + + xen_register_pirq(irq, -1 /* no GSI override */, + trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE, + true /* Map GSI to PIRQ */); + } + if (0 == nr_ioapics) { + for (irq = 0; irq < nr_legacy_irqs(); irq++) + xen_bind_pirq_gsi_to_irq(irq, irq, 0, "xt-pic"); + } + return 0; +} + +struct xen_device_domain_owner { + domid_t domain; + struct pci_dev *dev; + struct list_head list; +}; + +static DEFINE_SPINLOCK(dev_domain_list_spinlock); +static struct list_head dev_domain_list = LIST_HEAD_INIT(dev_domain_list); + +static struct xen_device_domain_owner *find_device(struct pci_dev *dev) +{ + struct xen_device_domain_owner *owner; + + list_for_each_entry(owner, &dev_domain_list, list) { + if (owner->dev == dev) + return owner; + } + return NULL; +} + +int xen_find_device_domain_owner(struct pci_dev *dev) +{ + struct xen_device_domain_owner *owner; + int domain = -ENODEV; + + spin_lock(&dev_domain_list_spinlock); + owner = find_device(dev); + if (owner) + domain = owner->domain; + spin_unlock(&dev_domain_list_spinlock); + return domain; +} +EXPORT_SYMBOL_GPL(xen_find_device_domain_owner); + +int xen_register_device_domain_owner(struct pci_dev *dev, uint16_t domain) +{ + struct xen_device_domain_owner *owner; + + owner = kzalloc(sizeof(struct xen_device_domain_owner), GFP_KERNEL); + if (!owner) + return -ENODEV; + + spin_lock(&dev_domain_list_spinlock); + if (find_device(dev)) { + spin_unlock(&dev_domain_list_spinlock); + kfree(owner); + return -EEXIST; + } + owner->domain = domain; + owner->dev = dev; + list_add_tail(&owner->list, &dev_domain_list); + spin_unlock(&dev_domain_list_spinlock); + return 0; +} +EXPORT_SYMBOL_GPL(xen_register_device_domain_owner); + +int xen_unregister_device_domain_owner(struct pci_dev *dev) +{ + struct xen_device_domain_owner *owner; + + spin_lock(&dev_domain_list_spinlock); + owner = find_device(dev); + if (!owner) { + spin_unlock(&dev_domain_list_spinlock); + return -ENODEV; + } + list_del(&owner->list); + spin_unlock(&dev_domain_list_spinlock); + kfree(owner); + return 0; +} +EXPORT_SYMBOL_GPL(xen_unregister_device_domain_owner); +#endif |