Commit 668192b6 authored by Yinghai Lu's avatar Yinghai Lu Committed by Bjorn Helgaas
Browse files

PCI: acpiphp: Move host bridge hotplug to pci_root.c 



The acpiphp driver is confusing because it contains partial support for PCI
host bridge hotplug as well as support for hotplug of PCI devices.

This patch moves the host bridge hot-add support to pci_root.c and adds
hot-remove support in pci_root.c.

How to test it: if sci_emu patch is applied, find out root bus number to
ACPI root name mapping from dmesg or /sys.  To remove root bus:

  echo "\_SB.PCIB 3" > /sys/kernel/debug/acpi/sci_notify

To add back root bus:

  echo "\_SB.PCIB 1" > /sys/kernel/debug/acpi/sci_notify

Signed-off-by: default avatarYinghai Lu <yinghai@kernel.org>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Acked-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 92d8aff3

drivers/acpi/internal.h

+1 −0
Original line number Diff line number Diff line
@@ -68,6 +68,7 @@ struct acpi_ec { 
extern struct acpi_ec *first_ec;



int acpi_pci_root_init(void);

void acpi_pci_root_hp_init(void);

int acpi_ec_init(void);

int acpi_ec_ecdt_probe(void);

int acpi_boot_ec_enable(void);

drivers/acpi/pci_root.c

+124 −0
Original line number Diff line number Diff line
@@ -673,3 +673,127 @@ int __init acpi_pci_root_init(void) 


	return 0;

}

/* Support root bridge hotplug */



static void handle_root_bridge_insertion(acpi_handle handle)

{

	struct acpi_device *device;



	if (!acpi_bus_get_device(handle, &device)) {

		printk(KERN_DEBUG "acpi device exists...\n");

		return;

	}



	if (acpi_bus_scan(handle))

		printk(KERN_ERR "cannot add bridge to acpi list\n");

}



static void handle_root_bridge_removal(struct acpi_device *device)

{

	struct acpi_eject_event *ej_event;



	ej_event = kmalloc(sizeof(*ej_event), GFP_KERNEL);

	if (!ej_event) {

		/* Inform firmware the hot-remove operation has error */

		(void) acpi_evaluate_hotplug_ost(device->handle,

					ACPI_NOTIFY_EJECT_REQUEST,

					ACPI_OST_SC_NON_SPECIFIC_FAILURE,

					NULL);

		return;

	}



	ej_event->device = device;

	ej_event->event = ACPI_NOTIFY_EJECT_REQUEST;



	acpi_bus_hot_remove_device(ej_event);

}



static void _handle_hotplug_event_root(struct work_struct *work)

{

	struct acpi_pci_root *root;

	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER };

	struct acpi_hp_work *hp_work;

	acpi_handle handle;

	u32 type;



	hp_work = container_of(work, struct acpi_hp_work, work);

	handle = hp_work->handle;

	type = hp_work->type;



	root = acpi_pci_find_root(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__,

				 (char *)buffer.pointer);

		if (!root)

			handle_root_bridge_insertion(handle);



		break;



	case ACPI_NOTIFY_DEVICE_CHECK:

		/* device check */

		printk(KERN_DEBUG "%s: Device check notify on %s\n", __func__,

				 (char *)buffer.pointer);

		if (!root)

			handle_root_bridge_insertion(handle);

		break;



	case ACPI_NOTIFY_EJECT_REQUEST:

		/* request device eject */

		printk(KERN_DEBUG "%s: Device eject notify on %s\n", __func__,

				 (char *)buffer.pointer);

		if (root)

			handle_root_bridge_removal(root->device);

		break;

	default:

		printk(KERN_WARNING "notify_handler: unknown event type 0x%x for %s\n",

				 type, (char *)buffer.pointer);

		break;

	}



	kfree(hp_work); /* allocated in handle_hotplug_event_bridge */

	kfree(buffer.pointer);

}



static void handle_hotplug_event_root(acpi_handle handle, u32 type,

					void *context)

{

	alloc_acpi_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);



	return AE_OK;

}



void __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);

}

drivers/acpi/scan.c

+3 −0
Original line number Diff line number Diff line
@@ -1706,5 +1706,8 @@ int __init acpi_scan_init(void) 
	}



	acpi_update_all_gpes();



	acpi_pci_root_hp_init();



	return 0;

}

drivers/pci/hotplug/acpiphp_glue.c

+15 −44
Original line number Diff line number Diff line
@@ -543,10 +543,13 @@ static void cleanup_bridge(struct acpiphp_bridge *bridge) 
	acpi_status status;

	acpi_handle handle = bridge->handle;



	status = acpi_remove_notify_handler(handle, ACPI_SYSTEM_NOTIFY,

	if (bridge->type != BRIDGE_TYPE_HOST) {

		status = acpi_remove_notify_handler(handle,

					    ACPI_SYSTEM_NOTIFY,

					    handle_hotplug_event_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)) {
@@ -630,9 +633,6 @@ static void remove_bridge(struct acpi_pci_root *root) 
	bridge = acpiphp_handle_to_bridge(handle);

	if (bridge)

		cleanup_bridge(bridge);

	else

		acpi_remove_notify_handler(handle, ACPI_SYSTEM_NOTIFY,

					   handle_hotplug_event_bridge);

}



static int power_on_slot(struct acpiphp_slot *slot)
@@ -1123,18 +1123,12 @@ static void acpiphp_sanitize_bus(struct pci_bus *bus) 
}



/* Program resources in newly inserted bridge */

static int acpiphp_configure_bridge (acpi_handle handle)

static int acpiphp_configure_p2p_bridge(acpi_handle handle)

{

	struct pci_bus *bus;



	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;

	struct pci_bus *bus = pdev->subordinate;



	pci_dev_put(pdev);

	}



	pci_bus_size_bridges(bus);

	pci_bus_assign_resources(bus);
@@ -1144,7 +1138,7 @@ static int acpiphp_configure_bridge (acpi_handle handle) 
	return 0;

}



static void handle_bridge_insertion(acpi_handle handle, u32 type)

static void handle_p2p_bridge_insertion(acpi_handle handle, u32 type)

{

	struct acpi_device *device;
@@ -1162,8 +1156,8 @@ static void handle_bridge_insertion(acpi_handle handle, u32 type) 
		err("ACPI device object missing\n");

		return;

	}

	if (!acpiphp_configure_bridge(handle))

		add_bridge(handle);

	if (!acpiphp_configure_p2p_bridge(handle))

		add_p2p_bridge(handle);

	else

		err("cannot configure and start bridge\n");
@@ -1221,7 +1215,7 @@ static void _handle_hotplug_event_bridge(struct work_struct *work) 


	if (acpi_bus_get_device(handle, &device)) {

		/* This bridge must have just been physically inserted */

		handle_bridge_insertion(handle, type);

		handle_p2p_bridge_insertion(handle, type);

		goto out;

	}
@@ -1396,21 +1390,6 @@ static void handle_hotplug_event_func(acpi_handle handle, u32 type, 
	alloc_acpi_hp_work(handle, type, context, _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,
@@ -1421,14 +1400,6 @@ 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);



	return 0;

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