[PATCH -v3 27/47] PCI, acpiphp: Separate out hot-add support of pci host bridge

From: Yinghai Lu
Date: Mon Mar 19 2012 - 02:01:03 EST


It causes confusion.

We may only need acpi hp for pci host bridge.

Split host bridge hot-add support to pci_root_hp, and keep acpiphp simple.

Also remove not used res_lock in the struct.

-v2: put back pci_root_hp change in one patch
-v3: add pcibios_resource_survey_bus() calling

Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>
---
drivers/acpi/Makefile | 1 +
drivers/acpi/pci_root_hp.c | 238 ++++++++++++++++++++++++++++++++++++
drivers/pci/hotplug/acpiphp.h | 9 +--
drivers/pci/hotplug/acpiphp_glue.c | 104 +++-------------
4 files changed, 260 insertions(+), 92 deletions(-)
create mode 100644 drivers/acpi/pci_root_hp.c

diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index 1567028..bc6e53f 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -36,6 +36,7 @@ acpi-y += processor_core.o
acpi-y += ec.o
acpi-$(CONFIG_ACPI_DOCK) += dock.o
acpi-y += pci_root.o pci_link.o pci_irq.o pci_bind.o
+acpi-$(CONFIG_HOTPLUG) += pci_root_hp.o
acpi-y += power.o
acpi-y += event.o
acpi-y += sysfs.o
diff --git a/drivers/acpi/pci_root_hp.c b/drivers/acpi/pci_root_hp.c
new file mode 100644
index 0000000..e07c31b
--- /dev/null
+++ b/drivers/acpi/pci_root_hp.c
@@ -0,0 +1,238 @@
+/*
+ * Separated from drivers/pci/hotplug/acpiphp_glue.c
+ * only support root bridge
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/acpi.h>
+
+static LIST_HEAD(acpi_root_bridge_list);
+struct acpi_root_bridge {
+ struct list_head list;
+ acpi_handle handle;
+ u32 flags;
+};
+
+/* bridge flags */
+#define ROOT_BRIDGE_HAS_EJ0 (0x00000002)
+#define ROOT_BRIDGE_HAS_PS3 (0x00000080)
+
+#define ACPI_STA_FUNCTIONING (0x00000008)
+
+static struct acpi_root_bridge *acpi_root_handle_to_bridge(acpi_handle handle)
+{
+ struct acpi_root_bridge *bridge;
+
+ list_for_each_entry(bridge, &acpi_root_bridge_list, list)
+ if (bridge->handle == handle)
+ return bridge;
+
+ return NULL;
+}
+
+/* allocate and initialize host bridge data structure */
+static void add_acpi_root_bridge(acpi_handle handle)
+{
+ struct acpi_root_bridge *bridge;
+ acpi_handle dummy_handle;
+ acpi_status status;
+
+ /* if the bridge doesn't have _STA, we assume it is always there */
+ status = acpi_get_handle(handle, "_STA", &dummy_handle);
+ if (ACPI_SUCCESS(status)) {
+ unsigned long long tmp;
+
+ status = acpi_evaluate_integer(handle, "_STA", NULL, &tmp);
+ if (ACPI_FAILURE(status)) {
+ printk(KERN_DEBUG "%s: _STA evaluation failure\n",
+ __func__);
+ return;
+ }
+ if ((tmp & ACPI_STA_FUNCTIONING) == 0)
+ /* don't register this object */
+ return;
+ }
+
+ bridge = kzalloc(sizeof(struct acpi_root_bridge), GFP_KERNEL);
+ if (!bridge)
+ return;
+
+ bridge->handle = handle;
+
+ if (ACPI_SUCCESS(acpi_get_handle(handle, "_EJ0", &dummy_handle)))
+ bridge->flags |= ROOT_BRIDGE_HAS_EJ0;
+ if (ACPI_SUCCESS(acpi_get_handle(handle, "_PS3", &dummy_handle)))
+ bridge->flags |= ROOT_BRIDGE_HAS_PS3;
+
+ list_add(&bridge->list, &acpi_root_bridge_list);
+}
+
+struct acpi_root_hp_work {
+ struct work_struct work;
+ acpi_handle handle;
+ u32 type;
+ void *context;
+};
+
+static void alloc_acpi_root_hp_work(acpi_handle handle, u32 type,
+ void *context,
+ void (*func)(struct work_struct *work))
+{
+ struct acpi_root_hp_work *hp_work;
+ int ret;
+
+ hp_work = kmalloc(sizeof(*hp_work), GFP_KERNEL);
+ if (!hp_work)
+ return;
+
+ hp_work->handle = handle;
+ hp_work->type = type;
+ hp_work->context = context;
+
+ INIT_WORK(&hp_work->work, func);
+ ret = queue_work(kacpi_hotplug_wq, &hp_work->work);
+ if (!ret)
+ kfree(hp_work);
+}
+
+/* Program resources in newly inserted bridge */
+static void acpi_root_configure_bridge(acpi_handle handle)
+{
+ struct acpi_pci_root *root = acpi_pci_find_root(handle);
+
+ pcibios_resource_survey_bus(root->bus);
+ pci_assign_unassigned_bus_resources(root->bus);
+}
+
+static void handle_root_bridge_insertion(acpi_handle handle)
+{
+ struct acpi_device *device, *pdevice;
+ acpi_handle phandle;
+ int ret_val;
+
+ acpi_get_parent(handle, &phandle);
+ if (acpi_bus_get_device(phandle, &pdevice)) {
+ printk(KERN_DEBUG "no parent device, assuming NULL\n");
+ pdevice = NULL;
+ }
+ if (!acpi_bus_get_device(handle, &device)) {
+ /* check if pci root_bus is removed */
+ struct acpi_pci_root *root = acpi_driver_data(device);
+ if (pci_find_bus(root->segment, root->secondary.start))
+ return;
+
+ printk(KERN_DEBUG "bus exists... trim\n");
+ /* this shouldn't be in here, so remove
+ * the bus then re-add it...
+ */
+ ret_val = acpi_bus_trim(device, 1);
+ printk(KERN_DEBUG "acpi_bus_trim return %x\n", ret_val);
+ }
+ if (acpi_bus_add(&device, pdevice, handle, ACPI_BUS_TYPE_DEVICE)) {
+ printk(KERN_ERR "cannot add bridge to acpi list\n");
+ return;
+ }
+ acpi_root_configure_bridge(handle);
+ if (acpi_bus_start(device))
+ printk(KERN_ERR "cannot start bridge\n");
+}
+
+static void _handle_hotplug_event_root(struct work_struct *work)
+{
+ struct acpi_root_bridge *bridge;
+ char objname[64];
+ struct acpi_buffer buffer = { .length = sizeof(objname),
+ .pointer = objname };
+ struct acpi_root_hp_work *hp_work;
+ acpi_handle handle;
+ u32 type;
+
+ hp_work = container_of(work, struct acpi_root_hp_work, work);
+ handle = hp_work->handle;
+ type = hp_work->type;
+
+ bridge = acpi_root_handle_to_bridge(handle);
+
+ acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
+
+ switch (type) {
+ case ACPI_NOTIFY_BUS_CHECK:
+ /* bus enumerate */
+ printk(KERN_DEBUG "%s: Bus check notify on %s\n", __func__,
+ objname);
+ if (!bridge) {
+ handle_root_bridge_insertion(handle);
+ add_acpi_root_bridge(handle);
+ }
+
+ break;
+
+ case ACPI_NOTIFY_DEVICE_CHECK:
+ /* device check */
+ printk(KERN_DEBUG "%s: Device check notify on %s\n", __func__,
+ objname);
+ if (!bridge) {
+ handle_root_bridge_insertion(handle);
+ add_acpi_root_bridge(handle);
+ }
+ break;
+
+ default:
+ printk(KERN_WARNING "notify_handler: unknown event type 0x%x for %s\n",
+ type, objname);
+ break;
+ }
+
+ kfree(hp_work); /* allocated in handle_hotplug_event_bridge */
+}
+
+static void handle_hotplug_event_root(acpi_handle handle, u32 type,
+ void *context)
+{
+ alloc_acpi_root_hp_work(handle, type, context,
+ _handle_hotplug_event_root);
+}
+
+static acpi_status __init
+find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv)
+{
+ char objname[64];
+ struct acpi_buffer buffer = { .length = sizeof(objname),
+ .pointer = objname };
+ int *count = (int *)context;
+
+ if (!acpi_is_root_bridge(handle))
+ return AE_OK;
+
+ (*count)++;
+
+ acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
+
+ acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
+ handle_hotplug_event_root, NULL);
+ printk(KERN_DEBUG "acpi root: %s notify handler installed\n", objname);
+
+ add_acpi_root_bridge(handle);
+
+ return AE_OK;
+}
+
+static int __init acpi_pci_root_hp_init(void)
+{
+ int num = 0;
+
+ acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
+ ACPI_UINT32_MAX, find_root_bridges, NULL, &num, NULL);
+
+ printk(KERN_DEBUG "Found %d acpi root devices\n", num);
+
+ return 0;
+}
+
+subsys_initcall(acpi_pci_root_hp_init);
diff --git a/drivers/pci/hotplug/acpiphp.h b/drivers/pci/hotplug/acpiphp.h
index 7722108..1a62e7b 100644
--- a/drivers/pci/hotplug/acpiphp.h
+++ b/drivers/pci/hotplug/acpiphp.h
@@ -79,18 +79,15 @@ struct acpiphp_bridge {
/* Ejectable PCI-to-PCI bridge (PCI bridge and PCI function) */
struct acpiphp_func *func;

- int type;
int nr_slots;

u32 flags;

- /* This bus (host bridge) or Secondary bus (PCI-to-PCI bridge) */
+ /* Secondary bus (PCI-to-PCI bridge) */
struct pci_bus *pci_bus;

/* PCI-to-PCI bridge device */
struct pci_dev *pci_dev;
-
- spinlock_t res_lock;
};


@@ -148,10 +145,6 @@ struct acpiphp_attention_info
/* PCI bus bridge HID */
#define ACPI_PCI_HOST_HID "PNP0A03"

-/* PCI BRIDGE type */
-#define BRIDGE_TYPE_HOST 0
-#define BRIDGE_TYPE_P2P 1
-
/* ACPI _STA method value (ignore bit 4; battery present) */
#define ACPI_STA_PRESENT (0x00000001)
#define ACPI_STA_ENABLED (0x00000002)
diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c
index 6aaf9ff..ae78c3d 100644
--- a/drivers/pci/hotplug/acpiphp_glue.c
+++ b/drivers/pci/hotplug/acpiphp_glue.c
@@ -283,7 +283,7 @@ static int detect_ejectable_slots(acpi_handle handle)
return found;
}

-/* initialize miscellaneous stuff for both root and PCI-to-PCI bridge */
+/* initialize miscellaneous stuff for PCI-to-PCI bridge */
static void init_bridge_misc(struct acpiphp_bridge *bridge)
{
acpi_status status;
@@ -300,25 +300,21 @@ static void init_bridge_misc(struct acpiphp_bridge *bridge)
}

/* install notify handler */
- if (bridge->type != BRIDGE_TYPE_HOST) {
- if ((bridge->flags & BRIDGE_HAS_EJ0) && bridge->func) {
- status = acpi_remove_notify_handler(bridge->func->handle,
- ACPI_SYSTEM_NOTIFY,
- handle_hotplug_event_func);
- if (ACPI_FAILURE(status))
- err("failed to remove notify handler\n");
- }
- 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 ((bridge->flags & BRIDGE_HAS_EJ0) && bridge->func) {
+ status = acpi_remove_notify_handler(bridge->func->handle,
+ ACPI_SYSTEM_NOTIFY,
+ handle_hotplug_event_func);
+ if (ACPI_FAILURE(status))
+ err("failed to remove notify handler\n");
}
-}
+ 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");
+}

/* find acpiphp_func from acpiphp_bridge */
static struct acpiphp_func *acpiphp_bridge_handle_to_function(acpi_handle handle)
@@ -375,28 +371,6 @@ static inline void config_p2p_bridge_flags(struct acpiphp_bridge *bridge)
}
}

-
-/* allocate and initialize host bridge data structure */
-static void add_host_bridge(acpi_handle *handle)
-{
- struct acpiphp_bridge *bridge;
- struct acpi_pci_root *root = acpi_pci_find_root(handle);
-
- bridge = kzalloc(sizeof(struct acpiphp_bridge), GFP_KERNEL);
- if (bridge == NULL)
- return;
-
- bridge->type = BRIDGE_TYPE_HOST;
- bridge->handle = handle;
-
- bridge->pci_bus = root->bus;
-
- spin_lock_init(&bridge->res_lock);
-
- init_bridge_misc(bridge);
-}
-
-
/* allocate and initialize PCI-to-PCI bridge data structure */
static void add_p2p_bridge(acpi_handle *handle)
{
@@ -408,7 +382,6 @@ static void add_p2p_bridge(acpi_handle *handle)
return;
}

- bridge->type = BRIDGE_TYPE_P2P;
bridge->handle = handle;
config_p2p_bridge_flags(bridge);

@@ -425,7 +398,6 @@ static void add_p2p_bridge(acpi_handle *handle)
* (which we access during module unload).
*/
get_device(&bridge->pci_bus->dev);
- spin_lock_init(&bridge->res_lock);

init_bridge_misc(bridge);
return;
@@ -485,12 +457,6 @@ static int add_bridge(acpi_handle handle)
return 0;
}

- /* check if this bridge has ejectable slots */
- if (detect_ejectable_slots(handle) > 0) {
- dbg("found PCI host-bus bridge with hot-pluggable slots\n");
- add_host_bridge(handle);
- }
-
/* search P2P bridges under this host bridge */
status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,
find_p2p_bridge, NULL, NULL, NULL);
@@ -524,8 +490,7 @@ static void cleanup_bridge(struct acpiphp_bridge *bridge)
if (ACPI_FAILURE(status))
err("failed to remove notify handler\n");

- if ((bridge->type != BRIDGE_TYPE_HOST) &&
- ((bridge->flags & BRIDGE_HAS_EJ0) && bridge->func)) {
+ if ((bridge->flags & BRIDGE_HAS_EJ0) && bridge->func) {
status = acpi_install_notify_handler(bridge->func->handle,
ACPI_SYSTEM_NOTIFY,
handle_hotplug_event_func,
@@ -1079,15 +1044,10 @@ static void acpiphp_sanitize_bus(struct pci_bus *bus)
static int acpiphp_configure_bridge (acpi_handle handle)
{
struct pci_bus *bus;
+ struct pci_dev *pdev = acpi_get_pci_dev(handle);

- if (acpi_is_root_bridge(handle)) {
- struct acpi_pci_root *root = acpi_pci_find_root(handle);
- bus = root->bus;
- } else {
- struct pci_dev *pdev = acpi_get_pci_dev(handle);
- bus = pdev->subordinate;
- pci_dev_put(pdev);
- }
+ bus = pdev->subordinate;
+ pci_dev_put(pdev);

pci_bus_size_bridges(bus);
pci_bus_assign_resources(bus);
@@ -1250,8 +1210,7 @@ static void _handle_hotplug_event_bridge(struct work_struct *work)
case ACPI_NOTIFY_EJECT_REQUEST:
/* request device eject */
dbg("%s: Device eject notify on %s\n", __func__, objname);
- if ((bridge->type != BRIDGE_TYPE_HOST) &&
- (bridge->flags & BRIDGE_HAS_EJ0)) {
+ if (bridge->flags & BRIDGE_HAS_EJ0) {
struct acpiphp_slot *slot;
slot = bridge->func->slot;
if (!acpiphp_disable_slot(slot))
@@ -1382,21 +1341,6 @@ static void handle_hotplug_event_func(acpi_handle handle, u32 type,
_handle_hotplug_event_func);
}

-static acpi_status
-find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv)
-{
- int *count = (int *)context;
-
- if (!acpi_is_root_bridge(handle))
- return AE_OK;
-
- (*count)++;
- acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
- handle_hotplug_event_bridge, NULL);
-
- return AE_OK ;
-}
-
static struct acpi_pci_driver acpi_pci_hp_driver = {
.add = add_bridge,
.remove = remove_bridge,
@@ -1407,15 +1351,7 @@ static struct acpi_pci_driver acpi_pci_hp_driver = {
*/
int __init acpiphp_glue_init(void)
{
- int num = 0;
-
- acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
- ACPI_UINT32_MAX, find_root_bridges, NULL, &num, NULL);
-
- if (num <= 0)
- return -1;
- else
- acpi_pci_register_driver(&acpi_pci_hp_driver);
+ acpi_pci_register_driver(&acpi_pci_hp_driver);

return 0;
}
--
1.7.7

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