diff options
Diffstat (limited to 'kernel/drivers/acpi/ioapic.c')
| -rw-r--r-- | kernel/drivers/acpi/ioapic.c | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/kernel/drivers/acpi/ioapic.c b/kernel/drivers/acpi/ioapic.c new file mode 100644 index 000000000..ccdc8db16 --- /dev/null +++ b/kernel/drivers/acpi/ioapic.c @@ -0,0 +1,229 @@ +/* + * IOAPIC/IOxAPIC/IOSAPIC driver + * + * Copyright (C) 2009 Fujitsu Limited. + * (c) Copyright 2009 Hewlett-Packard Development Company, L.P. + * + * Copyright (C) 2014 Intel Corporation + * + * 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. + * + * Based on original drivers/pci/ioapic.c + * Yinghai Lu <yinghai@kernel.org> + * Jiang Liu <jiang.liu@intel.com> + */ + +/* + * This driver manages I/O APICs added by hotplug after boot. + * We try to claim all I/O APIC devices, but those present at boot were + * registered when we parsed the ACPI MADT. + */ + +#define pr_fmt(fmt) "ACPI : IOAPIC: " fmt + +#include <linux/slab.h> +#include <linux/acpi.h> +#include <linux/pci.h> +#include <acpi/acpi.h> + +struct acpi_pci_ioapic { + acpi_handle root_handle; + acpi_handle handle; + u32 gsi_base; + struct resource res; + struct pci_dev *pdev; + struct list_head list; +}; + +static LIST_HEAD(ioapic_list); +static DEFINE_MUTEX(ioapic_list_lock); + +static acpi_status setup_res(struct acpi_resource *acpi_res, void *data) +{ + struct resource *res = data; + struct resource_win win; + + res->flags = 0; + if (acpi_dev_filter_resource_type(acpi_res, IORESOURCE_MEM) == 0) + return AE_OK; + + if (!acpi_dev_resource_memory(acpi_res, res)) { + if (acpi_dev_resource_address_space(acpi_res, &win) || + acpi_dev_resource_ext_address_space(acpi_res, &win)) + *res = win.res; + } + if ((res->flags & IORESOURCE_PREFETCH) || + (res->flags & IORESOURCE_DISABLED)) + res->flags = 0; + + return AE_CTRL_TERMINATE; +} + +static bool acpi_is_ioapic(acpi_handle handle, char **type) +{ + acpi_status status; + struct acpi_device_info *info; + char *hid = NULL; + bool match = false; + + if (!acpi_has_method(handle, "_GSB")) + return false; + + status = acpi_get_object_info(handle, &info); + if (ACPI_SUCCESS(status)) { + if (info->valid & ACPI_VALID_HID) + hid = info->hardware_id.string; + if (hid) { + if (strcmp(hid, "ACPI0009") == 0) { + *type = "IOxAPIC"; + match = true; + } else if (strcmp(hid, "ACPI000A") == 0) { + *type = "IOAPIC"; + match = true; + } + } + kfree(info); + } + + return match; +} + +static acpi_status handle_ioapic_add(acpi_handle handle, u32 lvl, + void *context, void **rv) +{ + acpi_status status; + unsigned long long gsi_base; + struct acpi_pci_ioapic *ioapic; + struct pci_dev *dev = NULL; + struct resource *res = NULL; + char *type = NULL; + + if (!acpi_is_ioapic(handle, &type)) + return AE_OK; + + mutex_lock(&ioapic_list_lock); + list_for_each_entry(ioapic, &ioapic_list, list) + if (ioapic->handle == handle) { + mutex_unlock(&ioapic_list_lock); + return AE_OK; + } + + status = acpi_evaluate_integer(handle, "_GSB", NULL, &gsi_base); + if (ACPI_FAILURE(status)) { + acpi_handle_warn(handle, "failed to evaluate _GSB method\n"); + goto exit; + } + + ioapic = kzalloc(sizeof(*ioapic), GFP_KERNEL); + if (!ioapic) { + pr_err("cannot allocate memory for new IOAPIC\n"); + goto exit; + } else { + ioapic->root_handle = (acpi_handle)context; + ioapic->handle = handle; + ioapic->gsi_base = (u32)gsi_base; + INIT_LIST_HEAD(&ioapic->list); + } + + if (acpi_ioapic_registered(handle, (u32)gsi_base)) + goto done; + + dev = acpi_get_pci_dev(handle); + if (dev && pci_resource_len(dev, 0)) { + if (pci_enable_device(dev) < 0) + goto exit_put; + pci_set_master(dev); + if (pci_request_region(dev, 0, type)) + goto exit_disable; + res = &dev->resource[0]; + ioapic->pdev = dev; + } else { + pci_dev_put(dev); + dev = NULL; + + res = &ioapic->res; + acpi_walk_resources(handle, METHOD_NAME__CRS, setup_res, res); + if (res->flags == 0) { + acpi_handle_warn(handle, "failed to get resource\n"); + goto exit_free; + } else if (request_resource(&iomem_resource, res)) { + acpi_handle_warn(handle, "failed to insert resource\n"); + goto exit_free; + } + } + + if (acpi_register_ioapic(handle, res->start, (u32)gsi_base)) { + acpi_handle_warn(handle, "failed to register IOAPIC\n"); + goto exit_release; + } +done: + list_add(&ioapic->list, &ioapic_list); + mutex_unlock(&ioapic_list_lock); + + if (dev) + dev_info(&dev->dev, "%s at %pR, GSI %u\n", + type, res, (u32)gsi_base); + else + acpi_handle_info(handle, "%s at %pR, GSI %u\n", + type, res, (u32)gsi_base); + + return AE_OK; + +exit_release: + if (dev) + pci_release_region(dev, 0); + else + release_resource(res); +exit_disable: + if (dev) + pci_disable_device(dev); +exit_put: + pci_dev_put(dev); +exit_free: + kfree(ioapic); +exit: + mutex_unlock(&ioapic_list_lock); + *(acpi_status *)rv = AE_ERROR; + return AE_OK; +} + +int acpi_ioapic_add(struct acpi_pci_root *root) +{ + acpi_status status, retval = AE_OK; + + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, root->device->handle, + UINT_MAX, handle_ioapic_add, NULL, + root->device->handle, (void **)&retval); + + return ACPI_SUCCESS(status) && ACPI_SUCCESS(retval) ? 0 : -ENODEV; +} + +int acpi_ioapic_remove(struct acpi_pci_root *root) +{ + int retval = 0; + struct acpi_pci_ioapic *ioapic, *tmp; + + mutex_lock(&ioapic_list_lock); + list_for_each_entry_safe(ioapic, tmp, &ioapic_list, list) { + if (root->device->handle != ioapic->root_handle) + continue; + + if (acpi_unregister_ioapic(ioapic->handle, ioapic->gsi_base)) + retval = -EBUSY; + + if (ioapic->pdev) { + pci_release_region(ioapic->pdev, 0); + pci_disable_device(ioapic->pdev); + pci_dev_put(ioapic->pdev); + } else if (ioapic->res.flags && ioapic->res.parent) { + release_resource(&ioapic->res); + } + list_del(&ioapic->list); + kfree(ioapic); + } + mutex_unlock(&ioapic_list_lock); + + return retval; +} |