/*
* IOAPIC/IOxAPIC/IOSAPIC driver
*
* Copyright (C) 2009 Fujitsu Limited.
* (c) Copyright 2009 Hewlett-Packard Development Company, L.P.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
/*
* This driver manages PCI I/O APICs added by hotplug after boot. We try to
* claim all I/O APIC PCI devices, but those present at boot were registered
* when we parsed the ACPI MADT, so we'll fail when we try to re-register
* them.
*/
#include <linux/pci.h>
#include <linux/module.h>
#include <linux/acpi.h>
#include <linux/slab.h>
#include <acpi/acpi_bus.h>
struct ioapic {
acpi_handle handle;
u32 gsi_base;
};
static int __devinit ioapic_probe(struct pci_dev *dev, const struct pci_device_id *ent)
{
acpi_handle handle;
acpi_status status;
unsigned long long gsb;
struct ioapic *ioapic;
int ret;
char *type;
struct resource *res;
handle = DEVICE_ACPI_HANDLE(&dev->dev);
if (!handle)
return -EINVAL;
status = acpi_evaluate_integer(handle, "_GSB", NULL, &gsb);
if (ACPI_FAILURE(status))
return -EINVAL;
/*
* The previous code in acpiphp evaluated _MAT if _GSB failed, but
* ACPI spec 4.0 sec 6.2.2 requires _GSB for hot-pluggable I/O APICs.
*/
ioapic = kzalloc(sizeof(*ioapic), GFP_KERNEL);
if (!ioapic)
return -ENOMEM;
ioapic->handle = handle;
ioapic->gsi_base = (u32) gsb;
if (dev->class == PCI_CLASS_SYSTEM_PIC_IOAPIC)
type = "IOAPIC";
else
type = "IOxAPIC";
ret = pci_enable_device(dev);
if (ret < 0)
goto exit_free;
pci_set_master(dev);
if (pci_request_region(dev, 0, type))
goto exit_disable;
res = &dev->resource[0];
if (acpi_register_ioapic(ioapic->handle, res->start, ioapic->gsi_base))
goto exit_release;
pci_set_drvdata(dev, ioapic);
dev_info(&dev->dev, "%s at %pR, GSI %u\n", type, res, ioapic->gsi_base);
return 0;
exit_release:
pci_release_region(dev, 0);
exit_disable:
pci_disable_device(dev);
exit_free:
kfree(ioapic);
return -ENODEV;
}
static void __devexit ioapic_remove(struct pci_dev *dev)
{
struct ioapic *ioapic = pci_get_drvdata(dev);
acpi_unregister_ioapic(ioapic->handle, ioapic->gsi_base);
pci_release_region(dev, 0);
pci_disable_device(dev);
kfree(ioapic);
}
static DEFINE_PCI_DEVICE_TABLE(ioapic_devices) = {
{ PCI_DEVICE_CLASS(PCI_CLASS_SYSTEM_PIC_IOAPIC, ~0) },
{ PCI_DEVICE_CLASS(PCI_CLASS_SYSTEM_PIC_IOXAPIC, ~0) },
{ }
};
MODULE_DEVICE_TABLE(pci, ioapic_devices);
static struct pci_driver ioapic_driver = {
.name = "ioapic",
.id_table = ioapic_devices,
.probe = ioapic_probe,
.remove = __devexit_p(ioapic_remove),
};
static int __init ioapic_init(void)
{
return pci_register_driver(&ioapic_driver);
}
static void __exit ioapic_exit(void)
{
pci_unregister_driver(&ioapic_driver);
}
module_init(ioapic_init);
module_exit(ioapic_exit);
