/*
* Xen PCI Frontend Stub - puts some "dummy" functions in to the Linux
* x86 PCI core to support the Xen PCI Frontend
*
* Author: Ryan Wilson <hap9@epoch.ncsc.mil>
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/acpi.h>
#include <linux/io.h>
#include <asm/pci_x86.h>
#include <asm/xen/hypervisor.h>
#include <xen/features.h>
#include <xen/events.h>
#include <asm/xen/pci.h>
#ifdef CONFIG_ACPI
static int xen_hvm_register_pirq(u32 gsi, int triggering)
{
int rc, irq;
struct physdev_map_pirq map_irq;
int shareable = 0;
char *name;
if (!xen_hvm_domain())
return -1;
map_irq.domid = DOMID_SELF;
map_irq.type = MAP_PIRQ_TYPE_GSI;
map_irq.index = gsi;
map_irq.pirq = -1;
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";
}
irq = xen_map_pirq_gsi(map_irq.pirq, gsi, shareable, name);
printk(KERN_DEBUG "xen: --> irq=%d, pirq=%d\n", irq, map_irq.pirq);
return irq;
}
static int acpi_register_gsi_xen_hvm(struct device *dev, u32 gsi,
int trigger, int polarity)
{
return xen_hvm_register_pirq(gsi, trigger);
}
#endif
#if defined(CONFIG_PCI_MSI)
#include <linux/msi.h>
struct xen_pci_frontend_ops *xen_pci_frontend;
EXPORT_SYMBOL_GPL(xen_pci_frontend);
/*
* For MSI interrupts we have to use drivers/xen/event.s functions to
* allocate an irq_desc and setup the right */
static int xen_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
{
int irq, ret, i;
struct msi_desc *msidesc;
int *v;
v = kzalloc(sizeof(int) * max(1, nvec), GFP_KERNEL);
if (!v)
return -ENOMEM;
if (!xen_initial_domain()) {
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_allocate_pirq(v[i], 0, /* not sharable */
(type == PCI_CAP_ID_MSIX) ?
"pcifront-msi-x" : "pcifront-msi");
if (irq < 0)
return -1;
ret = set_irq_msi(irq, msidesc);
if (ret)
goto error_while;
i++;
}
kfree(v);
return 0;
error_while:
unbind_from_irqhandler(irq, NULL);
error:
if (ret == -ENODEV)
dev_err(&dev->dev, "Xen PCI frontend has not registered" \
" MSI/MSI-X support!\n");
kfree(v);
return ret;
}
static void xen_teardown_msi_irqs(struct pci_dev *dev)
{
/* Only do this when were are in non-privileged mode.*/
if (!xen_initial_domain()) {
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);
}
}
static void xen_teardown_msi_irq(unsigned int irq)
{
xen_destroy_irq(irq);
}
#endif
static int xen_pcifront_enable_irq(struct pci_dev *dev)
{
int rc;
int share = 1;
dev_info(&dev->dev, "Xen PCI enabling IRQ: %d\n", dev->irq);
if (dev->irq < 0)
return -EINVAL;
if (dev->irq < NR_IRQS_LEGACY)
share = 0;
rc = xen_allocate_pirq(dev->irq, share, "pcifront");
if (rc < 0) {
dev_warn(&dev->dev, "Xen PCI IRQ: %d, failed to register:%d\n",
dev->irq, rc);
return rc;
}
return 0;
}
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;
#endif
return 0;
}
int __init pci_xen_hvm_init(void)
{
if (!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;
#endif
return 0;
}
