xen: remap GSIs as pirqs when running as initial domain

Implement xen_register_gsi to setup the correct triggering and polarity
properties of a gsi.
Implement xen_register_pirq to register a particular gsi as pirq and
receive interrupts as events.
Call xen_setup_pirqs to register all the legacy ISA irqs as pirqs.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

diff --git a/arch/x86/include/asm/xen/pci.h b/arch/x86/include/asm/xen/pci.h
index f89a42a..2329b3e 100644 (file)
--- a/arch/x86/include/asm/xen/pci.h
+++ b/arch/x86/include/asm/xen/pci.h
@@ -13,6 +13,13 @@ static inline int pci_xen_hvm_init(void)
        return -1;
 }
 #endif
+#if defined(CONFIG_XEN_DOM0)
+void __init xen_setup_pirqs(void);
+#else
+static inline void __init xen_setup_pirqs(void)
+{
+}
+#endif
 
 #if defined(CONFIG_PCI_MSI)
 #if defined(CONFIG_PCI_XEN)

diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index b5bd642..dd0b5fd 100644 (file)
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -257,3 +257,138 @@ int __init pci_xen_hvm_init(void)
 #endif
        return 0;
 }
+
+#ifdef CONFIG_XEN_DOM0
+static int xen_register_pirq(u32 gsi, int triggering)
+{
+       int rc, irq;
+       struct physdev_map_pirq map_irq;
+       int shareable = 0;
+       char *name;
+
+       if (!xen_pv_domain())
+               return -1;
+
+       if (triggering == ACPI_EDGE_SENSITIVE) {
+               shareable = 0;
+               name = "ioapic-edge";
+       } else {
+               shareable = 1;
+               name = "ioapic-level";
+       }
+
+       irq = xen_allocate_pirq(gsi, shareable, name);
+
+       printk(KERN_DEBUG "xen: --> irq=%d\n", irq);
+
+       if (irq < 0)
+               goto out;
+
+       map_irq.domid = DOMID_SELF;
+       map_irq.type = MAP_PIRQ_TYPE_GSI;
+       map_irq.index = gsi;
+       map_irq.pirq = irq;
+
+       rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
+       if (rc) {
+               printk(KERN_WARNING "xen map irq failed %d\n", rc);
+               return -1;
+       }
+
+out:
+       return irq;
+}
+
+static int xen_register_gsi(u32 gsi, 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, triggering);
+
+       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 __init void xen_setup_acpi_sci(void)
+{
+       int rc;
+       int trigger, polarity;
+       int gsi = acpi_sci_override_gsi;
+
+       if (!gsi)
+               return;
+
+       rc = acpi_get_override_irq(gsi, &trigger, &polarity);
+       if (rc) {
+               printk(KERN_WARNING "xen: acpi_get_override_irq failed for acpi"
+                               " sci, rc=%d\n", rc);
+               return;
+       }
+       trigger = trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE;
+       polarity = polarity ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH;
+       
+       printk(KERN_INFO "xen: sci override: global_irq=%d trigger=%d "
+                       "polarity=%d\n", gsi, trigger, polarity);
+
+       gsi = xen_register_gsi(gsi, trigger, polarity);
+       printk(KERN_INFO "xen: acpi sci %d\n", gsi);
+
+       return;
+}
+
+static int acpi_register_gsi_xen(struct device *dev, u32 gsi,
+                                int trigger, int polarity)
+{
+       return xen_register_gsi(gsi, trigger, polarity);
+}
+
+static int __init pci_xen_initial_domain(void)
+{
+       xen_setup_acpi_sci();
+       __acpi_register_gsi = acpi_register_gsi_xen;
+
+       return 0;
+}
+
+void __init xen_setup_pirqs(void)
+{
+       int irq;
+
+       pci_xen_initial_domain();
+
+       if (0 == nr_ioapics) {
+               for (irq = 0; irq < NR_IRQS_LEGACY; irq++)
+                       xen_allocate_pirq(irq, 0, "xt-pic");
+               return;
+       }
+
+       /* Pre-allocate legacy irqs */
+       for (irq = 0; irq < NR_IRQS_LEGACY; irq++) {
+               int trigger, polarity;
+
+               if (acpi_get_override_irq(irq, &trigger, &polarity) == -1)
+                       continue;
+
+               xen_register_pirq(irq,
+                       trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE);
+       }
+}
+#endif

diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index efa683e..c649ac0 100644 (file)
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -681,6 +681,8 @@ out:
 int xen_destroy_irq(int irq)
 {
        struct irq_desc *desc;
+       struct physdev_unmap_pirq unmap_irq;
+       struct irq_info *info = info_for_irq(irq);
        int rc = -ENOENT;
 
        spin_lock(&irq_mapping_update_lock);
@@ -689,6 +691,15 @@ int xen_destroy_irq(int irq)
        if (!desc)
                goto out;
 
+       if (xen_initial_domain()) {
+               unmap_irq.pirq = info->u.pirq.gsi;
+               unmap_irq.domid = DOMID_SELF;
+               rc = HYPERVISOR_physdev_op(PHYSDEVOP_unmap_pirq, &unmap_irq);
+               if (rc) {
+                       printk(KERN_WARNING "unmap irq failed %d\n", rc);
+                       goto out;
+               }
+       }
        irq_info[irq] = mk_unbound_info();
 
        irq_free_desc(irq);
@@ -1425,5 +1436,7 @@ void __init xen_init_IRQ(void)
                pci_xen_hvm_init();
        } else {
                irq_ctx_init(smp_processor_id());
+               if (xen_initial_domain())
+                       xen_setup_pirqs();
        }
 }

diff --git a/include/xen/interface/physdev.h b/include/xen/interface/physdev.h
index 69a72b9..a85d76c 100644 (file)
--- a/include/xen/interface/physdev.h
+++ b/include/xen/interface/physdev.h
@@ -151,6 +151,16 @@ struct physdev_op {
        } u;
 };
 
+#define PHYSDEVOP_setup_gsi    21
+struct physdev_setup_gsi {
+    int gsi;
+    /* IN */
+    uint8_t triggering;
+    /* IN */
+    uint8_t polarity;
+    /* IN */
+};
+
 #define PHYSDEVOP_get_nr_pirqs    22
 struct physdev_nr_pirqs {
     /* OUT */