[PATCH] acpi hotplug: aCPI based root bridge hot-add

acpiphp changes to support acpi based root bridge hot-add.

Signed-off-by: Rajesh Shah <rajesh.shah@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 202 insertions, 9 deletions

diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c
index 1501eb26af33..a6270cc218f6 100644
--- a/drivers/pci/hotplug/acpiphp_glue.c
+++ b/drivers/pci/hotplug/acpiphp_glue.c
@@ -6,6 +6,8 @@
  * Copyright (C) 2002,2003 NEC Corporation
  * Copyright (C) 2003-2005 Matthew Wilcox (matthew.wilcox@hp.com)
  * Copyright (C) 2003-2005 Hewlett Packard
+ * Copyright (C) 2005 Rajesh Shah (rajesh.shah@intel.com)
+ * Copyright (C) 2005 Intel Corporation
  *
  * All rights reserved.
  *
@@ -304,13 +306,15 @@ static void init_bridge_misc(struct acpiphp_bridge *bridge)
                                      register_slot, bridge, NULL);
 
         /* install notify handler */
-        status = acpi_install_notify_handler(bridge->handle,
+        if (bridge->type != BRIDGE_TYPE_HOST) {
+                status = acpi_install_notify_handler(bridge->handle,
                                              ACPI_SYSTEM_NOTIFY,
                                              handle_hotplug_event_bridge,
                                              bridge);
 
-        if (ACPI_FAILURE(status)) {
-                err("failed to register interrupt notify handler\n");
+                if (ACPI_FAILURE(status)) {
+                        err("failed to register interrupt notify handler\n");
+                }
         }
 
         list_add(&bridge->list, &bridge_list);
@@ -820,6 +824,143 @@ static int acpiphp_check_bridge(struct acpiphp_bridge *bridge)
         return retval;
 }
 
+static void program_hpp(struct pci_dev *dev, struct acpiphp_bridge *bridge)
+{
+        u16 pci_cmd, pci_bctl;
+        struct pci_dev *cdev;
+
+        /* Program hpp values for this device */
+        if (!(dev->hdr_type == PCI_HEADER_TYPE_NORMAL ||
+                        (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE &&
+                        (dev->class >> 8) == PCI_CLASS_BRIDGE_PCI)))
+                return;
+        pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE,
+                        bridge->hpp.cache_line_size);
+        pci_write_config_byte(dev, PCI_LATENCY_TIMER,
+                        bridge->hpp.latency_timer);
+        pci_read_config_word(dev, PCI_COMMAND, &pci_cmd);
+        if (bridge->hpp.enable_SERR)
+                pci_cmd |= PCI_COMMAND_SERR;
+        else
+                pci_cmd &= ~PCI_COMMAND_SERR;
+        if (bridge->hpp.enable_PERR)
+                pci_cmd |= PCI_COMMAND_PARITY;
+        else
+                pci_cmd &= ~PCI_COMMAND_PARITY;
+        pci_write_config_word(dev, PCI_COMMAND, pci_cmd);
+
+        /* Program bridge control value and child devices */
+        if ((dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
+                pci_write_config_byte(dev, PCI_SEC_LATENCY_TIMER,
+                                bridge->hpp.latency_timer);
+                pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &pci_bctl);
+                if (bridge->hpp.enable_SERR)
+                        pci_bctl |= PCI_BRIDGE_CTL_SERR;
+                else
+                        pci_bctl &= ~PCI_BRIDGE_CTL_SERR;
+                if (bridge->hpp.enable_PERR)
+                        pci_bctl |= PCI_BRIDGE_CTL_PARITY;
+                else
+                        pci_bctl &= ~PCI_BRIDGE_CTL_PARITY;
+                pci_write_config_word(dev, PCI_BRIDGE_CONTROL, pci_bctl);
+                if (dev->subordinate) {
+                        list_for_each_entry(cdev, &dev->subordinate->devices,
+                                        bus_list)
+                                program_hpp(cdev, bridge);
+                }
+        }
+}
+
+static void acpiphp_set_hpp_values(acpi_handle handle, struct pci_bus *bus)
+{
+        struct acpiphp_bridge bridge;
+        struct pci_dev *dev;
+
+        memset(&bridge, 0, sizeof(bridge));
+        bridge.handle = handle;
+        decode_hpp(&bridge);
+        list_for_each_entry(dev, &bus->devices, bus_list)
+                program_hpp(dev, &bridge);
+
+}
+
+/*
+ * Remove devices for which we could not assign resources, call
+ * arch specific code to fix-up the bus
+ */
+static void acpiphp_sanitize_bus(struct pci_bus *bus)
+{
+        struct pci_dev *dev;
+        int i;
+        unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM;
+
+        list_for_each_entry(dev, &bus->devices, bus_list) {
+                for (i=0; i<PCI_BRIDGE_RESOURCES; i++) {
+                        struct resource *res = &dev->resource[i];
+                        if ((res->flags & type_mask) && !res->start &&
+                                        res->end) {
+                                /* Could not assign a required resources
+                                 * for this device, remove it */
+                                pci_remove_bus_device(dev);
+                                break;
+                        }
+                }
+        }
+}
+
+/* Program resources in newly inserted bridge */
+static int acpiphp_configure_bridge (acpi_handle handle)
+{
+        struct acpi_pci_id pci_id;
+        struct pci_bus *bus;
+
+        if (ACPI_FAILURE(acpi_get_pci_id(handle, &pci_id))) {
+                err("cannot get PCI domain and bus number for bridge\n");
+                return -EINVAL;
+        }
+        bus = pci_find_bus(pci_id.segment, pci_id.bus);
+        if (!bus) {
+                err("cannot find bus %d:%d\n",
+                                pci_id.segment, pci_id.bus);
+                return -EINVAL;
+        }
+
+        pci_bus_size_bridges(bus);
+        pci_bus_assign_resources(bus);
+        acpiphp_sanitize_bus(bus);
+        acpiphp_set_hpp_values(handle, bus);
+        pci_enable_bridges(bus);
+        return 0;
+}
+
+static void handle_bridge_insertion(acpi_handle handle, u32 type)
+{
+        struct acpi_device *device, *pdevice;
+        acpi_handle phandle;
+
+        if ((type != ACPI_NOTIFY_BUS_CHECK) &&
+                        (type != ACPI_NOTIFY_DEVICE_CHECK)) {
+                err("unexpected notification type %d\n", type);
+                return;
+        }
+
+        acpi_get_parent(handle, &phandle);
+        if (acpi_bus_get_device(phandle, &pdevice)) {
+                dbg("no parent device, assuming NULL\n");
+                pdevice = NULL;
+        }
+        if (acpi_bus_add(&device, pdevice, handle, ACPI_BUS_TYPE_DEVICE)) {
+                err("cannot add bridge to acpi list\n");
+                return;
+        }
+        if (!acpiphp_configure_bridge(handle) &&
+                !acpi_bus_start(device))
+                add_bridge(handle);
+        else
+                err("cannot configure and start bridge\n");
+
+}
+
 /*
  * ACPI event handlers
  */
@@ -840,8 +981,19 @@ static void handle_hotplug_event_bridge(acpi_handle handle, u32 type, void *cont
         char objname[64];
         struct acpi_buffer buffer = { .length = sizeof(objname),
                                       .pointer = objname };
+        struct acpi_device *device;
 
-        bridge = (struct acpiphp_bridge *)context;
+        if (acpi_bus_get_device(handle, &device)) {
+                /* This bridge must have just been physically inserted */
+                handle_bridge_insertion(handle, type);
+                return;
+        }
+
+        bridge = acpiphp_handle_to_bridge(handle);
+        if (!bridge) {
+                err("cannot get bridge info\n");
+                return;
+        }
 
         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 
@@ -941,6 +1093,47 @@ static void handle_hotplug_event_func(acpi_handle handle, u32 type, void *contex
         }
 }
 
+static int is_root_bridge(acpi_handle handle)
+{
+        acpi_status status;
+        struct acpi_device_info *info;
+        struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
+        int i;
+
+        status = acpi_get_object_info(handle, &buffer);
+        if (ACPI_SUCCESS(status)) {
+                info = buffer.pointer;
+                if ((info->valid & ACPI_VALID_HID) &&
+                        !strcmp(PCI_ROOT_HID_STRING,
+                                        info->hardware_id.value)) {
+                        acpi_os_free(buffer.pointer);
+                        return 1;
+                }
+                if (info->valid & ACPI_VALID_CID) {
+                        for (i=0; i < info->compatibility_id.count; i++) {
+                                if (!strcmp(PCI_ROOT_HID_STRING,
+                                        info->compatibility_id.id[i].value)) {
+                                        acpi_os_free(buffer.pointer);
+                                        return 1;
+                                }
+                        }
+                }
+        }
+        return 0;
+}
+
+static acpi_status
+find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv)
+{
+        int *count = (int *)context;
+
+        if (is_root_bridge(handle)) {
+                acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
+                                handle_hotplug_event_bridge, NULL);
+                        (*count)++;
+        }
+        return AE_OK ;
+}
 
 static struct acpi_pci_driver acpi_pci_hp_driver = {
         .add =          add_bridge,
@@ -953,15 +1146,15 @@ static struct acpi_pci_driver acpi_pci_hp_driver = {
  */
 int __init acpiphp_glue_init(void)
 {
-        int num;
-
-        if (list_empty(&pci_root_buses))
-                return -1;
+        int num = 0;
 
-        num = acpi_pci_register_driver(&acpi_pci_hp_driver);
+        acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
+                        ACPI_UINT32_MAX, find_root_bridges, &num, NULL);
 
         if (num <= 0)
                 return -1;
+        else
+                acpi_pci_register_driver(&acpi_pci_hp_driver);
 
         return 0;
 }