[PATCH 01/12] xen: remap GSIs as pirqs when running as initial domain

stefano.stabellini
2010-09-28T12:17:30Z

From: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>

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>
---
arch/x86/pci/xen.c | 144 ++++++++++++++++++++++++++++++++++++++-
drivers/xen/events.c | 13 ++++
include/xen/events.h | 2 +
include/xen/interface/physdev.h | 10 +++
4 files changed, 168 insertions(+), 1 deletions(-)

diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index 6fbc81a..cb8d5be 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -18,6 +18,108 @@
#include <xen/events.h>
#include <asm/xen/pci.h>

+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;
+}
+
+#ifdef CONFIG_ACPI
+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)
+ return;
+ trigger = trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE;
+ polarity = polarity ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH;
+
+ printk("xen: sci override: global_irq=%d trigger=%d polarity=%d\n",
+ gsi, trigger, polarity);
+
+ gsi = xen_register_gsi(gsi, trigger, polarity);
+ /*
+ * stash over-ride to indicate we've been here
+ * and for later update of acpi_gbl_FADT
+ */
+ printk("xen: acpi sci %d\n", gsi);
+
+ return;
+}
+#else
+static __init void xen_setup_acpi_sci(void)
+{
+}
+#endif
+
int xen_hvm_register_pirq(u32 gsi, int triggering)
{
int rc, irq;
@@ -211,10 +313,15 @@ static int acpi_register_gsi_xen_hvm(struct device *dev, u32 gsi,
return xen_hvm_register_pirq(gsi, trigger);
}

+static int acpi_register_gsi_xen(struct device *dev, u32 gsi,
+ int trigger, int polarity)
+{
+ return xen_register_gsi(gsi, trigger, polarity);
+}

int __init pci_xen_init(void)
{
- if (!xen_pv_domain() || xen_initial_domain())
+ if (!xen_pv_domain() || xen_initial_domain())
return -ENODEV;

printk(KERN_INFO "PCI: setting up Xen PCI frontend stub\n");
@@ -242,6 +349,41 @@ int __init pci_xen_init(void)
return 0;
}

+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;
+#ifndef CONFIG_SMP
+ int nr_ioapics = 1;
+#endif
+
+ 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);
+ }
+}
+
int __init pci_xen_hvm_init(void)
{
if (!xen_feature(XENFEAT_hvm_pirqs))
diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index a31677e..27e4b70 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -676,6 +676,8 @@ 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);
@@ -684,6 +686,15 @@ 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();

dynamic_irq_cleanup(irq);
@@ -1410,5 +1421,7 @@ 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/events.h b/include/xen/events.h
index 5e67be7..9853fce 100644
--- a/include/xen/events.h
+++ b/include/xen/events.h
@@ -84,4 +84,6 @@ int xen_vector_from_irq(unsigned pirq);
/* Return gsi allocated to pirq */
int xen_gsi_from_irq(unsigned pirq);

+void xen_setup_pirqs(void);
+
#endif /* _XEN_EVENTS_H */
diff --git a/include/xen/interface/physdev.h b/include/xen/interface/physdev.h
index 69a72b9..a85d76c 100644
--- 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 */
--
1.5.6.5