Message-Id: <1351958865-24394-2-git-send-email-jiang.liu@huawei.com>
Date:	Sun,  4 Nov 2012 00:07:42 +0800
From:	Jiang Liu <liuj97@...il.com>
To:	"Rafael J . Wysocki" <rjw@...k.pl>,
	Yinghai Lu <yinghai@...nel.org>,
	Tony Luck <tony.luck@...el.com>,
	Yasuaki Ishimatsu <isimatu.yasuaki@...fujitsu.com>,
	Wen Congyang <wency@...fujitsu.com>,
	Tang Chen <tangchen@...fujitsu.com>,
	Taku Izumi <izumi.taku@...fujitsu.com>,
	Bjorn Helgaas <bhelgaas@...gle.com>
Cc:	Jiang Liu <jiang.liu@...wei.com>,
	Kenji Kaneshige <kaneshige.kenji@...fujitsu.com>,
	Huang Ying <ying.huang@...el.com>,
	Bob Moore <robert.moore@...el.com>,
	Len Brown <lenb@...nel.org>,
	"Srivatsa S . Bhat" <srivatsa.bhat@...ux.vnet.ibm.com>,
	Yijing Wang <wangyijing@...wei.com>,
	Hanjun Guo <guohanjun@...wei.com>,
	Jiang Liu <liuj97@...il.com>, linux-kernel@...r.kernel.org,
	linux-acpi@...r.kernel.org, linux-pci@...r.kernel.org,
	linux-mm@...ck.org, Gaohuai Han <hangaohuai@...wei.com>
Subject: [ACPIHP PATCH part1 1/4] ACPIHP: introduce a framework for ACPI based system device hotplug

Modern high-end servers may support advanced RAS features, such as
system device dynamic reconfiguration. On x86 and IA64 platforms,
system device means processor(CPU), memory device, PCI host bridge
and even computer node.

The ACPI specifications have provided standard interfaces between
firmware and OS to support device dynamic reconfiguraiton at runtime.
This patch series introduces a new framework for system device
dynamic reconfiguration based on ACPI specification, which will
replace current existing system device hotplug logic embedded in
ACPI processor/memory/container device drivers.

The new ACPI based hotplug framework is modelled after the PCI hotplug
architecture and target to achieve following goals:
1) Optimize device configuration order to achieve best performance for
   hot-added system devices. For best perforamnce, system device should
   be configured in order of memory -> CPU -> IOAPIC/IOMMU -> PCI HB.
2) Resolve dependencies among hotplug slots. You need first to remove
   the memory device before removing a physical processor if a
   hotpluggable memory device is connected to a hotpluggable physical
   processor.
3) Provide interface to cancel ongoing hotplug operations. It may take
   a very long time to remove a memory device, so provide interface to
   cancel the inprogress hotplug operations.
4) Support new advanced RAS features, such as socket/memory migration.
5) Provide better user interfaces to access the hotplug functionalities.
6) Provide a mechanism to detect hotplug slots by checking existence
   of ACPI _EJ0 method or by other hardware platform specific methods.
7) Unify the way to enumerate ACPI based hotplug slots. All hotplug
   slots will be enumerated by the enumeration driver (acpihp_slot),
   instead of by individual ACPI device drivers.
8) Unify the way to handle ACPI hotplug events. All ACPI hotplug events
   for system devices will be handled by a generic ACPI hotplug driver
   (acpihp_drv) instead of by individual ACPI device drivers.
9) Provide better error handling and error recovery.
10) Trigger hotplug events/operations by software. This feature is useful
   for hardware fault management and/or power saving.

The new framework is composed up of three major components:
1) A system device hotplug slot enumerator driver, which enumerates
   hotplug slots in the system and provides platform specific methods
   to control those slots.
2) A system device hotplug driver, which is a platform independent
   driver to manage all hotplug slots created by the slot enumerator.
   The hotplug driver implements a state machine for hotplug slots and
   provides user interfaces to manage hotplug slots.
3) Several ACPI device drivers to configure/unconfigure system devices
   at runtime.

To get rid of inter dependengcy between the slot enumerator and hotplug
driver, common code shared by them will be built into the kernel. The
shared code provides some helper routines and a device class named
acpihp_slot_class with following default sysfs properties:
	capabilities: RAS capabilities of the hotplug slot
	state: current state of the hotplug slot state machine
	status: current health status of the hotplug slot
	object: ACPI object corresponding to the hotplug slot

Signed-off-by: Jiang Liu <jiang.liu@...wei.com>
Signed-off-by: Gaohuai Han <hangaohuai@...wei.com>
---
 drivers/acpi/Kconfig          |   13 +
 drivers/acpi/Makefile         |    2 +
 drivers/acpi/hotplug/Makefile |    6 +
 drivers/acpi/hotplug/acpihp.h |   32 +++
 drivers/acpi/hotplug/core.c   |  543 +++++++++++++++++++++++++++++++++++++++++
 include/acpi/acpi_hotplug.h   |  208 ++++++++++++++++
 6 files changed, 804 insertions(+)
 create mode 100644 drivers/acpi/hotplug/Makefile
 create mode 100644 drivers/acpi/hotplug/acpihp.h
 create mode 100644 drivers/acpi/hotplug/core.c
 create mode 100644 include/acpi/acpi_hotplug.h

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index 119d58d..9577b23 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -321,6 +321,19 @@ config X86_PM_TIMER
 	  You should nearly always say Y here because many modern
 	  systems require this timer. 
 
+menuconfig ACPI_HOTPLUG
+	bool "System Device Hotplug"
+	depends on (X86 || IA64) && SYSFS
+	default n
+	help
+	  This option enables a framework to dynamically reconfigure system
+	  devices at runtime based on ACPI specifications. On x86 and IA64
+	  platforms, system device includes processor(CPU), memory device,
+	  PCI/PCIe host bridge and computer node etc.
+
+	  If your hardware platform does not support system device dynamic
+	  reconfiguration at runtime, you need not to enable this option.
+
 config ACPI_CONTAINER
 	tristate "Container and Module Devices (EXPERIMENTAL)"
 	depends on EXPERIMENTAL
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index 47199e2..17bea6c 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -73,3 +73,5 @@ obj-$(CONFIG_ACPI_PROCESSOR_AGGREGATOR) += acpi_pad.o
 obj-$(CONFIG_ACPI_IPMI)		+= acpi_ipmi.o
 
 obj-$(CONFIG_ACPI_APEI)		+= apei/
+
+obj-$(CONFIG_ACPI_HOTPLUG)	+= hotplug/
diff --git a/drivers/acpi/hotplug/Makefile b/drivers/acpi/hotplug/Makefile
new file mode 100644
index 0000000..5e7790f
--- /dev/null
+++ b/drivers/acpi/hotplug/Makefile
@@ -0,0 +1,6 @@
+#
+# Makefile for ACPI based system device hotplug drivers
+#
+
+obj-$(CONFIG_ACPI_HOTPLUG)			+= acpihp.o
+acpihp-y					= core.o
diff --git a/drivers/acpi/hotplug/acpihp.h b/drivers/acpi/hotplug/acpihp.h
new file mode 100644
index 0000000..7467895
--- /dev/null
+++ b/drivers/acpi/hotplug/acpihp.h
@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2012 Huawei Tech. Co., Ltd.
+ * Copyright (C) 2012 Jiang Liu <jiang.liu@...wei.com>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#ifndef	ACPIHP_INTERNAL_H
+#define	ACPIHP_INTERNAL_H
+#include <acpi/acpi.h>
+#include <acpi/acpi_bus.h>
+#include <acpi/acpi_hotplug.h>
+
+extern struct acpi_device *acpi_root;
+
+#endif
diff --git a/drivers/acpi/hotplug/core.c b/drivers/acpi/hotplug/core.c
new file mode 100644
index 0000000..c835a97
--- /dev/null
+++ b/drivers/acpi/hotplug/core.c
@@ -0,0 +1,543 @@
+/*
+ * Copyright (C) 2012 Huawei Tech. Co., Ltd.
+ * Copyright (C) 2012 Jiang Liu <jiang.liu@...wei.com>
+ * Copyright (C) 2012 Gaohuai Han <hangaohuai@...wei.com>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/acpi.h>
+#include <linux/bug.h>
+#include <linux/device.h>
+#include <linux/mutex.h>
+#include <linux/sem.h>
+#include <linux/version.h>
+#include <acpi/acpi.h>
+#include <acpi/acpi_bus.h>
+#include <acpi/acpi_hotplug.h>
+#include "acpihp.h"
+
+#define to_acpihp_slot(d) container_of(d, struct acpihp_slot, dev)
+
+static DEFINE_MUTEX(acpihp_mutex);
+static int acpihp_class_count;
+static struct kset *acpihp_slot_kset;
+
+static char *acpihp_slot_names[ACPIHP_SLOT_TYPE_MAX] = {
+	[ACPIHP_SLOT_TYPE_UNKNOWN]	= "UNKNOWN",
+	[ACPIHP_SLOT_TYPE_COMMON]	= "SLOT",
+	[ACPIHP_SLOT_TYPE_NODE]		= "NODE",
+	[ACPIHP_SLOT_TYPE_SYSTEM_BOARD]	= "SB",
+	[ACPIHP_SLOT_TYPE_CPU]		= "CPU",
+	[ACPIHP_SLOT_TYPE_MEM]		= "MEM",
+	[ACPIHP_SLOT_TYPE_IOX]		= "IOX",
+};
+
+static char *acpihp_slot_states[] = {
+	[ACPIHP_SLOT_STATE_UNKNOWN]		= "unknown",
+	[ACPIHP_SLOT_STATE_ABSENT]		= "absent",
+	[ACPIHP_SLOT_STATE_PRESENT]		= "present",
+	[ACPIHP_SLOT_STATE_POWERED]		= "powered",
+	[ACPIHP_SLOT_STATE_CONNECTED]		= "connected",
+	[ACPIHP_SLOT_STATE_CONFIGURED]		= "configured",
+	[ACPIHP_SLOT_STATE_POWERING_ON]		= "powering on",
+	[ACPIHP_SLOT_STATE_POWERING_OFF]	= "powering off",
+	[ACPIHP_SLOT_STATE_CONNECTING]		= "connecting",
+	[ACPIHP_SLOT_STATE_DISCONNECTING]	= "disconneting",
+	[ACPIHP_SLOT_STATE_CONFIGURING]		= "configuring",
+	[ACPIHP_SLOT_STATE_UNCONFIGURING]	= "unconfiguring",
+};
+
+static char *acpihp_slot_status[] = {
+	"ok",
+	"irremovable",
+	"fault",
+	"irremovable, fault",
+};
+
+static char *acpihp_dev_container_ids[] = {
+	"ACPI0004",
+	"PNP0A05",
+	"PNP0A06",
+	NULL
+};
+
+static char *acpihp_dev_cpu_ids[] = {
+	"ACPI0007",
+	"LNXCPU",
+	NULL
+};
+
+static char *acpihp_dev_mem_ids[] = {
+	"PNP0C80",
+	NULL
+};
+
+static char *acpihp_dev_pcihb_ids[] = {
+	"PNP0A03",
+	NULL
+};
+
+static void acpihp_slot_release(struct device *dev)
+{
+	struct acpihp_slot *slot = to_acpihp_slot(dev);
+
+	kfree(slot);
+}
+
+/**
+ * acpihp_alloc_slot - allocate a hotplug slot for @handle
+ * @handle: the ACPI device handle to associated with the hotplug slot
+ * @name: optional name for the hotplug slot
+ *
+ * The returned data structure must be freed by calling acpihp_slot_put()
+ * instead of kfree().
+ */
+struct acpihp_slot *acpihp_alloc_slot(acpi_handle handle, char *name)
+{
+	struct acpihp_slot *slot;
+
+	if (name && strlen(name) >= ACPIHP_SLOT_NAME_MAX_SIZE) {
+		ACPIHP_DEBUG("slot name '%s' is too big.\n", name);
+		return NULL;
+	}
+
+	slot = kzalloc(sizeof(*slot), GFP_KERNEL);
+	if (slot == NULL) {
+		ACPIHP_DEBUG("fails to allocate memory for slot device.\n");
+		return NULL;
+	}
+
+	slot->handle = handle;
+	INIT_LIST_HEAD(&slot->slot_list);
+	INIT_LIST_HEAD(&slot->drvdata_list);
+	if (name)
+		strncpy(slot->name, name, sizeof(slot->name) - 1);
+	mutex_init(&slot->slot_mutex);
+
+	slot->dev.class = &acpihp_slot_class;
+	device_initialize(&slot->dev);
+
+	return slot;
+}
+EXPORT_SYMBOL_GPL(acpihp_alloc_slot);
+
+int acpihp_register_slot(struct acpihp_slot *slot)
+{
+	int ret;
+
+	if (!slot || !slot->slot_ops)
+		return -EINVAL;
+
+	/* Use ACPI root device to host top level hotplug slots */
+	if (slot->parent)
+		slot->dev.parent = &slot->parent->dev;
+	else
+		slot->dev.parent = &acpi_root->dev;
+
+	ret = device_add(&slot->dev);
+	if (!ret) {
+		slot->flags |= ACPIHP_SLOT_FLAG_REGISTERED;
+		if (sysfs_create_link(&acpihp_slot_kset->kobj, &slot->dev.kobj,
+				      slot->name))
+			dev_warn(&slot->dev, "fails to create symlink.\n");
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(acpihp_register_slot);
+
+void acpihp_unregister_slot(struct acpihp_slot *slot)
+{
+	if (slot && (slot->flags & ACPIHP_SLOT_FLAG_REGISTERED)) {
+		sysfs_remove_link(&acpihp_slot_kset->kobj, slot->name);
+		device_del(&slot->dev);
+		slot->flags &= ~ACPIHP_SLOT_FLAG_REGISTERED;
+	}
+}
+EXPORT_SYMBOL_GPL(acpihp_unregister_slot);
+
+struct acpihp_slot *acpihp_slot_get(struct acpihp_slot *slot)
+{
+	if (slot)
+		get_device(&slot->dev);
+
+	return slot;
+}
+EXPORT_SYMBOL_GPL(acpihp_slot_get);
+
+void acpihp_slot_put(struct acpihp_slot *slot)
+{
+	if (slot)
+		put_device(&slot->dev);
+}
+EXPORT_SYMBOL_GPL(acpihp_slot_put);
+
+static void acpihp_slot_data_handler(acpi_handle handle, void *context)
+{
+	return;
+}
+
+/* Bind the slot device to corresponding ACPI object handle */
+acpi_status acpihp_mark_slot(acpi_handle handle, struct acpihp_slot *slot)
+{
+	acpi_status status;
+
+	mutex_lock(&acpihp_mutex);
+	status = acpi_attach_data(handle, &acpihp_slot_data_handler, slot);
+	mutex_unlock(&acpihp_mutex);
+
+	return status;
+}
+EXPORT_SYMBOL_GPL(acpihp_mark_slot);
+
+acpi_status acpihp_unmark_slot(acpi_handle handle)
+{
+	acpi_status result;
+
+	mutex_lock(&acpihp_mutex);
+	result = acpi_detach_data(handle, &acpihp_slot_data_handler);
+	if (result == AE_NOT_FOUND)
+		result = AE_OK;
+	BUG_ON(result != AE_OK);
+	mutex_unlock(&acpihp_mutex);
+
+	return result;
+}
+EXPORT_SYMBOL_GPL(acpihp_unmark_slot);
+
+bool acpihp_is_slot(acpi_handle handle)
+{
+	acpi_status result;
+	void *data = NULL;
+
+	result = acpi_get_data(handle, &acpihp_slot_data_handler, &data);
+	BUG_ON(result != AE_OK && result != AE_NOT_FOUND);
+
+	return (result == AE_OK);
+}
+EXPORT_SYMBOL_GPL(acpihp_is_slot);
+
+struct acpihp_slot *acpihp_get_slot(acpi_handle handle)
+{
+	acpi_status result;
+	void *data = NULL;
+	struct acpihp_slot *slot = NULL;
+
+	mutex_lock(&acpihp_mutex);
+	result = acpi_get_data(handle, &acpihp_slot_data_handler, &data);
+	if (ACPI_SUCCESS(result) && data) {
+		slot = data;
+		acpihp_slot_get(slot);
+	}
+	mutex_unlock(&acpihp_mutex);
+
+	return slot;
+}
+EXPORT_SYMBOL_GPL(acpihp_get_slot);
+
+bool acpihp_dev_match_ids(struct acpi_device_info *infop, char **ids)
+{
+	int i, j;
+	struct acpica_device_id_list *cid_list;
+
+	if (infop == NULL || ids == NULL) {
+		ACPIHP_DEBUG("invalid parameters.\n");
+		return false;
+	}
+
+	if (infop->valid & ACPI_VALID_HID) {
+		for (i = 0; ids[i]; i++) {
+			if (strncmp(ids[i], infop->hardware_id.string,
+				    infop->hardware_id.length) == 0) {
+				return true;
+			}
+		}
+	}
+
+	if (infop->valid & ACPI_VALID_CID) {
+		for (i = 0; ids[i]; i++) {
+			cid_list = &infop->compatible_id_list;
+			for (j = 0; j < cid_list->count; j++) {
+				if (strncmp(ids[i],
+					    cid_list->ids[j].string,
+					    cid_list->ids[j].length) == 0) {
+						return true;
+				}
+			}
+		}
+	}
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(acpihp_dev_match_ids);
+
+int acpihp_dev_get_type(acpi_handle handle, enum acpihp_dev_type *type)
+{
+	struct acpi_device_info *infop = NULL;
+
+	if (handle == NULL || type == NULL) {
+		ACPIHP_DEBUG("invalid parameters.\n");
+		return -EINVAL;
+	}
+	if (ACPI_FAILURE(acpi_get_object_info(handle, &infop)))
+		return -ENODEV;
+
+	*type = ACPIHP_DEV_TYPE_UNKNOWN;
+	if (infop->type == ACPI_TYPE_PROCESSOR) {
+		*type = ACPIHP_DEV_TYPE_CPU;
+	} else if (infop->type == ACPI_TYPE_DEVICE) {
+		if (acpihp_dev_match_ids(infop, acpihp_dev_container_ids))
+			*type = ACPIHP_DEV_TYPE_CONTAINER;
+		else if (acpihp_dev_match_ids(infop, acpihp_dev_cpu_ids))
+			*type = ACPIHP_DEV_TYPE_CPU;
+		else if (acpihp_dev_match_ids(infop, acpihp_dev_mem_ids))
+			*type = ACPIHP_DEV_TYPE_MEM;
+		else if (acpihp_dev_match_ids(infop, acpihp_dev_pcihb_ids))
+			*type = ACPIHP_DEV_TYPE_HOST_BRIDGE;
+		else if ((infop->valid & (ACPI_VALID_ADR | ACPI_VALID_HID |
+			 ACPI_VALID_CID)) == ACPI_VALID_ADR)
+			*type = ACPIHP_DEV_TYPE_MAX;
+	}
+	kfree(infop);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(acpihp_dev_get_type);
+
+char *acpihp_get_slot_type_name(enum acpihp_slot_type type)
+{
+	if (type < 0 || type >= ACPIHP_SLOT_TYPE_MAX) {
+		ACPIHP_DEBUG("invalid parameters.\n");
+		return "UNKNOWN";
+	}
+
+	return acpihp_slot_names[type];
+}
+EXPORT_SYMBOL_GPL(acpihp_get_slot_type_name);
+
+acpi_status acpihp_slot_get_status(struct acpihp_slot *slot, u64 *status)
+{
+	acpi_status rc;
+
+	if (slot == NULL || status == NULL) {
+		ACPIHP_DEBUG("invalid parameters.\n");
+		return AE_BAD_PARAMETER;
+	} else if (slot->slot_ops == NULL) {
+		ACPIHP_SLOT_DEBUG(slot, "operation not supported.\n");
+		return AE_SUPPORT;
+	} else if (slot->slot_ops->get_status)
+		return slot->slot_ops->get_status(slot, status);
+
+	rc = acpi_evaluate_integer(slot->handle, METHOD_NAME__STA,
+				   NULL, status);
+	if (rc == AE_NOT_FOUND) {
+		*status = ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED |
+			  ACPI_STA_DEVICE_FUNCTIONING;
+		rc = AE_OK;
+	}
+
+	return rc;
+}
+EXPORT_SYMBOL_GPL(acpihp_slot_get_status);
+
+acpi_status acpihp_slot_poweron(struct acpihp_slot *slot)
+{
+	if (slot == NULL) {
+		ACPIHP_DEBUG("invalid parameter.\n");
+		return AE_BAD_PARAMETER;
+	} else if (slot->slot_ops == NULL || slot->slot_ops->poweron == NULL) {
+		ACPIHP_SLOT_DEBUG(slot, "operation not supported.\n");
+		return AE_SUPPORT;
+	}
+
+	return slot->slot_ops->poweron(slot->handle);
+}
+EXPORT_SYMBOL_GPL(acpihp_slot_poweron);
+
+acpi_status acpihp_slot_poweroff(struct acpihp_slot *slot)
+{
+	if (slot == NULL) {
+		ACPIHP_DEBUG("invalid parameter.\n");
+		return AE_BAD_PARAMETER;
+	} else if (slot->slot_ops == NULL || slot->slot_ops->poweroff == NULL) {
+		ACPIHP_SLOT_DEBUG(slot, "operation not supported.\n");
+		return AE_SUPPORT;
+	}
+
+	return slot->slot_ops->poweroff(slot->handle);
+}
+EXPORT_SYMBOL_GPL(acpihp_slot_poweroff);
+
+/* SYSFS interfaces */
+static ssize_t acpihp_slot_object_show(struct device *d,
+		struct device_attribute *attr, char *buf)
+{
+	acpi_status rc;
+	ssize_t sz = -EINVAL;
+	struct acpihp_slot *slot = to_acpihp_slot(d);
+	struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
+
+	rc = acpi_get_name(slot->handle, ACPI_FULL_PATHNAME, &path);
+	if (ACPI_SUCCESS(rc)) {
+		sz = snprintf(buf, PAGE_SIZE, "%s\n", (char *)path.pointer);
+		kfree(path.pointer);
+	}
+
+	return sz;
+}
+
+static ssize_t acpihp_slot_state_show(struct device *d,
+		struct device_attribute *attr, char *buf)
+{
+	enum acpihp_slot_state state;
+	acpi_status status;
+	unsigned long long sta;
+	struct acpihp_slot *slot = to_acpihp_slot(d);
+
+	state = slot->state < 0 || slot->state >= ACPIHP_SLOT_STATE_MAX ?
+		ACPIHP_SLOT_STATE_UNKNOWN : slot->state;
+
+	/*
+	 * There's no standard ACPI interfaces to notify the hotplug driver
+	 * when device presence changes, so check it for sure.
+	 */
+	if (ACPIHP_SLOT_STATE_ABSENT == state ||
+	    ACPIHP_SLOT_STATE_PRESENT == state) {
+		status = acpihp_slot_get_status(slot, &sta);
+		if (ACPI_SUCCESS(status)) {
+			if (sta & ACPI_STA_DEVICE_PRESENT)
+				state = ACPIHP_SLOT_STATE_PRESENT;
+			else
+				state = ACPIHP_SLOT_STATE_ABSENT;
+		}
+	}
+
+	return snprintf(buf, PAGE_SIZE, "%s\n", acpihp_slot_states[state]);
+}
+
+static ssize_t acpihp_slot_status_show(struct device *d,
+		struct device_attribute *attr, char *buf)
+{
+	struct acpihp_slot *slot = to_acpihp_slot(d);
+	u32 status = slot->flags & ACPIHP_SLOT_STATUS_MASK;
+
+	return snprintf(buf, PAGE_SIZE, "%s\n", acpihp_slot_status[status]);
+}
+
+static ssize_t acpihp_slot_capabilities_show(struct device *d,
+		struct device_attribute *attr, char *buf)
+{
+	ssize_t sz;
+	struct acpihp_slot *slot = to_acpihp_slot(d);
+	u32 cap = slot->capabilities;
+
+	sz = snprintf(buf, PAGE_SIZE, "%s%s%s%s%s%s",
+		(cap & ACPIHP_SLOT_CAP_ONLINE) ? "online," : "",
+		(cap & ACPIHP_SLOT_CAP_OFFLINE) ? "offline," : "",
+		(cap & ACPIHP_SLOT_CAP_POWERON) ? "poweron," : "",
+		(cap & ACPIHP_SLOT_CAP_POWEROFF) ? "poweroff," : "",
+		(cap & ACPIHP_SLOT_CAP_HOTPLUG) ? "hotplug," : "",
+		(cap & ACPIHP_SLOT_CAP_MIGRATE) ? "migrate," : "");
+
+	/* Change the last ',' to '\n' */
+	BUG_ON(sz == 0);
+	if (sz)
+		buf[sz - 1] = '\n';
+
+	return sz;
+}
+
+struct device_attribute acpihp_slot_dev_attrs[] = {
+	__ATTR(object, S_IRUGO, acpihp_slot_object_show, NULL),
+	__ATTR(state, S_IRUGO, acpihp_slot_state_show, NULL),
+	__ATTR(status, S_IRUGO, acpihp_slot_status_show, NULL),
+	__ATTR(capabilities, S_IRUGO, acpihp_slot_capabilities_show, NULL),
+	__ATTR_NULL
+};
+
+/* The device class to support ACPI hotplug slots. */
+struct class acpihp_slot_class = {
+	.name		= "acpihp",
+	.dev_release	= &acpihp_slot_release,
+	.dev_attrs	= acpihp_slot_dev_attrs,
+};
+EXPORT_SYMBOL_GPL(acpihp_slot_class);
+
+/* Initialize the ACPI based system device hotplug core logic */
+int acpihp_core_init(void)
+{
+	int retval = 0;
+	struct kset *acpi_bus_kset;
+
+	mutex_lock(&acpihp_mutex);
+	BUG_ON(acpihp_class_count < 0);
+
+	if (acpihp_class_count == 0) {
+		/* create directory /sys/bus/acpi/slots */
+		acpi_bus_kset = bus_get_kset(&acpi_bus_type);
+		acpihp_slot_kset = kset_create_and_add("slots", NULL,
+						       &acpi_bus_kset->kobj);
+		if (!acpihp_slot_kset) {
+			ACPIHP_DEBUG("fails to create kset.\n");
+			retval = -ENOMEM;
+			goto out_unlock;
+		}
+
+		retval = class_register(&acpihp_slot_class);
+		if (retval) {
+			ACPIHP_DEBUG("fails to register acpihp_slot_class.\n");
+			kset_unregister(acpihp_slot_kset);
+			goto out_unlock;
+		}
+	}
+
+	acpihp_class_count++;
+out_unlock:
+	mutex_unlock(&acpihp_mutex);
+
+	return retval;
+}
+EXPORT_SYMBOL_GPL(acpihp_core_init);
+
+/* Deinitialize the ACPI based system device hotplug core logic */
+void acpihp_core_fini(void)
+{
+	mutex_lock(&acpihp_mutex);
+	BUG_ON(acpihp_class_count <= 0);
+	--acpihp_class_count;
+	if (acpihp_class_count == 0) {
+		class_unregister(&acpihp_slot_class);
+		kset_unregister(acpihp_slot_kset);
+		acpihp_slot_kset = NULL;
+	}
+	mutex_unlock(&acpihp_mutex);
+}
+EXPORT_SYMBOL_GPL(acpihp_core_fini);
+
+#ifdef	DEBUG
+int acpihp_debug = 1;
+#else
+int acpihp_debug;
+#endif
+EXPORT_SYMBOL_GPL(acpihp_debug);
+module_param_named(debug, acpihp_debug, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(debug, "Enable debug mode");
diff --git a/include/acpi/acpi_hotplug.h b/include/acpi/acpi_hotplug.h
new file mode 100644
index 0000000..298f679
--- /dev/null
+++ b/include/acpi/acpi_hotplug.h
@@ -0,0 +1,208 @@
+/*
+ * Copyright (C) 2012 Huawei Tech. Co., Ltd.
+ * Copyright (C) 2012 Jiang Liu <jiang.liu@...wei.com>
+ * Copyright (C) 2012 Gaohuai Han <hangaohuai@...wei.com>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#ifndef	__ACPI_HOTPLUG_H__
+#define	__ACPI_HOTPLUG_H__
+#include <linux/types.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/klist.h>
+#include <acpi/acpi.h>
+#include <acpi/acpi_drivers.h>
+
+#ifdef	CONFIG_ACPI_HOTPLUG
+
+#define	ACPIHP_SLOT_NAME_MAX_SIZE		16
+
+/* Types of system devices supported by the ACPI hotplug framework. */
+enum acpihp_dev_type {
+	ACPIHP_DEV_TYPE_UNKNOWN = 0,	/* Unknown device type */
+	ACPIHP_DEV_TYPE_CONTAINER,	/* ACPI container device */
+	ACPIHP_DEV_TYPE_MEM,		/* Memory device */
+	ACPIHP_DEV_TYPE_CPU,		/* Logical CPU device */
+	ACPIHP_DEV_TYPE_HOST_BRIDGE,	/* PCI/PCIe host bridge */
+	ACPIHP_DEV_TYPE_MAX
+};
+
+/*
+ * ACPI hotplug slot is an abstraction of receptacles where a group of
+ * system devices could be attached, just like PCI slot in PCI hotplug.
+ */
+enum acpihp_slot_type {
+	ACPIHP_SLOT_TYPE_UNKNOWN = 0,	/* Unknown slot type */
+	ACPIHP_SLOT_TYPE_COMMON,	/* Generic hotplug slot */
+	ACPIHP_SLOT_TYPE_NODE,		/* Node hosts CPU, MEM & IO devices */
+	ACPIHP_SLOT_TYPE_SYSTEM_BOARD,	/* System board hosts CPU & MEM */
+	ACPIHP_SLOT_TYPE_CPU,		/* CPU board */
+	ACPIHP_SLOT_TYPE_MEM,		/* Memory board */
+	ACPIHP_SLOT_TYPE_IOX,		/* IO eXtension board */
+	ACPIHP_SLOT_TYPE_MAX
+};
+
+/*
+ * State machine for ACPI hotplug slot:
+ *                     (POWERON)      (CONNECT)      (CONFIGURE)
+ * [ABSENT] <-> [PRESENT] <-> [POWERED] <-> [CONNECTED] <-> [CONFIGURED]
+ *                     (POWEROFF)    (DISCONNECT)   (UNCONFIGURE)
+ *
+ * [ABSENT]: no devices attached to the slot
+ * [PRESENT]: devices attached to the slot but powered off
+ * [POWERED]: devices attached to the slot have been powered on
+ * [CONNECTED]: ACPI device objects have been created for devices attached
+ *              to the slot, and ACPI device drivers have been bound to the
+ *              ACPI device objects
+ * [CONFIGURED]: devices attached to the slot have been added into the
+ *               running system
+ */
+enum acpihp_slot_state {
+	ACPIHP_SLOT_STATE_UNKNOWN = 0,
+	ACPIHP_SLOT_STATE_ABSENT,	/* slot is empty. */
+	ACPIHP_SLOT_STATE_PRESENT,	/* slot is populated. */
+	ACPIHP_SLOT_STATE_POWERED,	/* attached devices are powered. */
+	ACPIHP_SLOT_STATE_CONNECTED,	/* ACPI device nodes created. */
+	ACPIHP_SLOT_STATE_CONFIGURED,	/* attached devices are configured. */
+	ACPIHP_SLOT_STATE_POWERING_ON,	/* powering devices on */
+	ACPIHP_SLOT_STATE_POWERING_OFF,	/* powering devices off */
+	ACPIHP_SLOT_STATE_CONNECTING,	/* creating ACPI device nodes */
+	ACPIHP_SLOT_STATE_DISCONNECTING,/* destroying ACPI device nodes */
+	ACPIHP_SLOT_STATE_CONFIGURING,	/* configuring devices */
+	ACPIHP_SLOT_STATE_UNCONFIGURING,/* unconfigure devices */
+	ACPIHP_SLOT_STATE_MAX
+};
+
+/* Devices attached to the slot can't be hot-removed. */
+#define	ACPIHP_SLOT_FLAG_IRREMOVABLE	0x1
+/* Devices attached to the slot have encountered serious problems. */
+#define	ACPIHP_SLOT_FLAG_FAULT		0x2
+#define	ACPIHP_SLOT_STATUS_MASK		0x3
+/* Internal flag: devices attached to the slot have been registered. */
+#define	ACPIHP_SLOT_FLAG_REGISTERED	0x80000000
+
+/* Capabilities of ACPI hotplug slot. */
+#define	ACPIHP_SLOT_CAP_ONLINE		0x1  /* Logical online */
+#define	ACPIHP_SLOT_CAP_OFFLINE		0x2  /* Logical offline */
+#define	ACPIHP_SLOT_CAP_POWERON		0x4  /* Physical power on */
+#define	ACPIHP_SLOT_CAP_POWEROFF	0x8  /* Physical power off */
+#define	ACPIHP_SLOT_CAP_HOTPLUG		0x10 /* Physical hotplug */
+#define	ACPIHP_SLOT_CAP_MIGRATE		0x20 /* Device migration */
+
+struct acpihp_slot;
+
+/*
+ * Callbacks provided by the platform dependent hotplug slot enumeration driver,
+ * which will be used by the platform independent ACPI hotplug framework to
+ * manage and control ACPI hotplug slots.
+ */
+struct acpihp_slot_ops {
+	struct module *owner;
+	char *desc;
+	acpi_status (*init)(void);
+	void (*fini)(void);					/* optional */
+	acpi_status (*check)(acpi_handle handle);
+	acpi_status (*create)(struct acpihp_slot *slot);
+	void (*destroy)(struct acpihp_slot *slot);		/* optional */
+	acpi_status (*poweron)(struct acpihp_slot *slot);	/* optional */
+	acpi_status (*poweroff)(struct acpihp_slot *slot);	/* optional */
+	acpi_status (*get_status)(struct acpihp_slot *slot,
+				  u64 *status);			/* optional */
+};
+
+/* Device structure for ACPI hotplug slots. */
+struct acpihp_slot {
+	struct device			dev;
+	acpi_handle			handle;
+	u32				capabilities;
+	u32				flags;
+	enum acpihp_slot_type		type;
+	enum acpihp_slot_state		state;
+	struct acpihp_slot		*parent;
+	struct acpihp_slot_ops		*slot_ops;
+	void				*slot_data;
+	struct mutex			slot_mutex;
+	struct list_head		slot_list;
+	struct list_head		drvdata_list;
+	struct klist			dev_lists[ACPIHP_DEV_TYPE_MAX];
+	char				name[ACPIHP_SLOT_NAME_MAX_SIZE];
+};
+
+/* Device class for ACPI hotplug slots */
+extern struct class acpihp_slot_class;
+
+/* Initialize the ACPI based system device hotplug core logic */
+extern int acpihp_core_init(void);
+
+/* Deinitialize the ACPI based system device hotplug core logic */
+extern void acpihp_core_fini(void);
+
+/* Utility routines */
+extern int acpihp_dev_get_type(acpi_handle handle, enum acpihp_dev_type *type);
+extern bool acpihp_dev_match_ids(struct acpi_device_info *infop, char **ids);
+extern char *acpihp_get_slot_type_name(enum acpihp_slot_type type);
+
+/* Mark/unmark an ACPI object as an ACPI hotplug slot. */
+extern acpi_status acpihp_mark_slot(acpi_handle handle,
+				    struct acpihp_slot *slot);
+extern acpi_status acpihp_unmark_slot(acpi_handle handle);
+
+/* Check whether the ACPI object is a hotplug slot. */
+extern bool acpihp_is_slot(acpi_handle handle);
+
+/* Interfaces to manage ACPI hotplug slots */
+extern struct acpihp_slot *acpihp_alloc_slot(acpi_handle handle, char *name);
+extern int acpihp_register_slot(struct acpihp_slot *slot);
+extern void acpihp_unregister_slot(struct acpihp_slot *slot);
+extern struct acpihp_slot *acpihp_slot_get(struct acpihp_slot *slot);
+extern void acpihp_slot_put(struct acpihp_slot *slot);
+extern struct acpihp_slot *acpihp_get_slot(acpi_handle handle);
+
+/* Platform dependent hotplug hooks */
+extern acpi_status acpihp_slot_get_status(struct acpihp_slot *slot,
+					  u64 *status);
+extern acpi_status acpihp_slot_poweron(struct acpihp_slot *slot);
+extern acpi_status acpihp_slot_poweroff(struct acpihp_slot *slot);
+
+extern int acpihp_debug;
+
+#define ACPIHP_WARN(fmt, ...) \
+	pr_warn("acpihp@%s: " fmt,  __func__, ##__VA_ARGS__)
+
+#define ACPIHP_DEBUG(fmt, ...) \
+	do { \
+		if (acpihp_debug & 0x01) \
+			pr_warn("acpihp@%s: " fmt,  __func__, ##__VA_ARGS__); \
+	} while (0)
+
+#define	ACPIHP_SLOT_DEBUG(slot, fmt, ...) \
+	do { \
+		if (acpihp_debug & 0x01) \
+			dev_warn(&(slot)->dev, fmt, ##__VA_ARGS__); \
+	} while (0)
+
+#define	ACPIHP_SLOT_WARN(slot, fmt, ...) \
+	dev_warn(&(slot)->dev, fmt, ##__VA_ARGS__)
+
+#endif	/* CONFIG_ACPI_HOTPLUG */
+
+#endif	/* __ACPI_HOTPLUG_H__ */
-- 
1.7.9.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists