zte's code,first commit

Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/drivers/acpi/acpi_memhotplug.c b/ap/os/linux/linux-3.4.x/drivers/acpi/acpi_memhotplug.c
new file mode 100644
index 0000000..f81597f
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/drivers/acpi/acpi_memhotplug.c
@@ -0,0 +1,578 @@
+/*
+ * Copyright (C) 2004 Intel Corporation <naveen.b.s@intel.com>
+ *
+ * All rights reserved.
+ *
+ * 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, GOOD TITLE or
+ * NON INFRINGEMENT.  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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ *
+ * ACPI based HotPlug driver that supports Memory Hotplug
+ * This driver fields notifications from firmware for memory add
+ * and remove operations and alerts the VM of the affected memory
+ * ranges.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/memory_hotplug.h>
+#include <linux/slab.h>
+#include <acpi/acpi_drivers.h>
+
+#define ACPI_MEMORY_DEVICE_CLASS		"memory"
+#define ACPI_MEMORY_DEVICE_HID			"PNP0C80"
+#define ACPI_MEMORY_DEVICE_NAME			"Hotplug Mem Device"
+
+#define _COMPONENT		ACPI_MEMORY_DEVICE_COMPONENT
+
+#undef PREFIX
+#define 	PREFIX		"ACPI:memory_hp:"
+
+ACPI_MODULE_NAME("acpi_memhotplug");
+MODULE_AUTHOR("Naveen B S <naveen.b.s@intel.com>");
+MODULE_DESCRIPTION("Hotplug Mem Driver");
+MODULE_LICENSE("GPL");
+
+/* Memory Device States */
+#define MEMORY_INVALID_STATE	0
+#define MEMORY_POWER_ON_STATE	1
+#define MEMORY_POWER_OFF_STATE	2
+
+static int acpi_memory_device_add(struct acpi_device *device);
+static int acpi_memory_device_remove(struct acpi_device *device, int type);
+
+static const struct acpi_device_id memory_device_ids[] = {
+	{ACPI_MEMORY_DEVICE_HID, 0},
+	{"", 0},
+};
+MODULE_DEVICE_TABLE(acpi, memory_device_ids);
+
+static struct acpi_driver acpi_memory_device_driver = {
+	.name = "acpi_memhotplug",
+	.class = ACPI_MEMORY_DEVICE_CLASS,
+	.ids = memory_device_ids,
+	.ops = {
+		.add = acpi_memory_device_add,
+		.remove = acpi_memory_device_remove,
+		},
+};
+
+struct acpi_memory_info {
+	struct list_head list;
+	u64 start_addr;		/* Memory Range start physical addr */
+	u64 length;		/* Memory Range length */
+	unsigned short caching;	/* memory cache attribute */
+	unsigned short write_protect;	/* memory read/write attribute */
+	unsigned int enabled:1;
+};
+
+struct acpi_memory_device {
+	struct acpi_device * device;
+	unsigned int state;	/* State of the memory device */
+	struct list_head res_list;
+};
+
+static int acpi_hotmem_initialized;
+
+static acpi_status
+acpi_memory_get_resource(struct acpi_resource *resource, void *context)
+{
+	struct acpi_memory_device *mem_device = context;
+	struct acpi_resource_address64 address64;
+	struct acpi_memory_info *info, *new;
+	acpi_status status;
+
+	status = acpi_resource_to_address64(resource, &address64);
+	if (ACPI_FAILURE(status) ||
+	    (address64.resource_type != ACPI_MEMORY_RANGE))
+		return AE_OK;
+
+	list_for_each_entry(info, &mem_device->res_list, list) {
+		/* Can we combine the resource range information? */
+		if ((info->caching == address64.info.mem.caching) &&
+		    (info->write_protect == address64.info.mem.write_protect) &&
+		    (info->start_addr + info->length == address64.minimum)) {
+			info->length += address64.address_length;
+			return AE_OK;
+		}
+	}
+
+	new = kzalloc(sizeof(struct acpi_memory_info), GFP_KERNEL);
+	if (!new)
+		return AE_ERROR;
+
+	INIT_LIST_HEAD(&new->list);
+	new->caching = address64.info.mem.caching;
+	new->write_protect = address64.info.mem.write_protect;
+	new->start_addr = address64.minimum;
+	new->length = address64.address_length;
+	list_add_tail(&new->list, &mem_device->res_list);
+
+	return AE_OK;
+}
+
+static int
+acpi_memory_get_device_resources(struct acpi_memory_device *mem_device)
+{
+	acpi_status status;
+	struct acpi_memory_info *info, *n;
+
+
+	if (!list_empty(&mem_device->res_list))
+		return 0;
+
+	status = acpi_walk_resources(mem_device->device->handle, METHOD_NAME__CRS,
+				     acpi_memory_get_resource, mem_device);
+	if (ACPI_FAILURE(status)) {
+		list_for_each_entry_safe(info, n, &mem_device->res_list, list)
+			kfree(info);
+		INIT_LIST_HEAD(&mem_device->res_list);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int
+acpi_memory_get_device(acpi_handle handle,
+		       struct acpi_memory_device **mem_device)
+{
+	acpi_status status;
+	acpi_handle phandle;
+	struct acpi_device *device = NULL;
+	struct acpi_device *pdevice = NULL;
+	int result;
+
+
+	if (!acpi_bus_get_device(handle, &device) && device)
+		goto end;
+
+	status = acpi_get_parent(handle, &phandle);
+	if (ACPI_FAILURE(status)) {
+		ACPI_EXCEPTION((AE_INFO, status, "Cannot find acpi parent"));
+		return -EINVAL;
+	}
+
+	/* Get the parent device */
+	result = acpi_bus_get_device(phandle, &pdevice);
+	if (result) {
+		printk(KERN_WARNING PREFIX "Cannot get acpi bus device");
+		return -EINVAL;
+	}
+
+	/*
+	 * Now add the notified device.  This creates the acpi_device
+	 * and invokes .add function
+	 */
+	result = acpi_bus_add(&device, pdevice, handle, ACPI_BUS_TYPE_DEVICE);
+	if (result) {
+		printk(KERN_WARNING PREFIX "Cannot add acpi bus");
+		return -EINVAL;
+	}
+
+      end:
+	*mem_device = acpi_driver_data(device);
+	if (!(*mem_device)) {
+		printk(KERN_ERR "\n driver data not found");
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static int acpi_memory_check_device(struct acpi_memory_device *mem_device)
+{
+	unsigned long long current_status;
+
+	/* Get device present/absent information from the _STA */
+	if (ACPI_FAILURE(acpi_evaluate_integer(mem_device->device->handle, "_STA",
+					       NULL, &current_status)))
+		return -ENODEV;
+	/*
+	 * Check for device status. Device should be
+	 * present/enabled/functioning.
+	 */
+	if (!((current_status & ACPI_STA_DEVICE_PRESENT)
+	      && (current_status & ACPI_STA_DEVICE_ENABLED)
+	      && (current_status & ACPI_STA_DEVICE_FUNCTIONING)))
+		return -ENODEV;
+
+	return 0;
+}
+
+static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
+{
+	int result, num_enabled = 0;
+	struct acpi_memory_info *info;
+	int node;
+
+
+	/* Get the range from the _CRS */
+	result = acpi_memory_get_device_resources(mem_device);
+	if (result) {
+		printk(KERN_ERR PREFIX "get_device_resources failed\n");
+		mem_device->state = MEMORY_INVALID_STATE;
+		return result;
+	}
+
+	node = acpi_get_node(mem_device->device->handle);
+	/*
+	 * Tell the VM there is more memory here...
+	 * Note: Assume that this function returns zero on success
+	 * We don't have memory-hot-add rollback function,now.
+	 * (i.e. memory-hot-remove function)
+	 */
+	list_for_each_entry(info, &mem_device->res_list, list) {
+		if (info->enabled) { /* just sanity check...*/
+			num_enabled++;
+			continue;
+		}
+		/*
+		 * If the memory block size is zero, please ignore it.
+		 * Don't try to do the following memory hotplug flowchart.
+		 */
+		if (!info->length)
+			continue;
+		if (node < 0)
+			node = memory_add_physaddr_to_nid(info->start_addr);
+
+		result = add_memory(node, info->start_addr, info->length);
+		if (result)
+			continue;
+		info->enabled = 1;
+		num_enabled++;
+	}
+	if (!num_enabled) {
+		printk(KERN_ERR PREFIX "add_memory failed\n");
+		mem_device->state = MEMORY_INVALID_STATE;
+		return -EINVAL;
+	}
+	/*
+	 * Sometimes the memory device will contain several memory blocks.
+	 * When one memory block is hot-added to the system memory, it will
+	 * be regarded as a success.
+	 * Otherwise if the last memory block can't be hot-added to the system
+	 * memory, it will be failure and the memory device can't be bound with
+	 * driver.
+	 */
+	return 0;
+}
+
+static int acpi_memory_powerdown_device(struct acpi_memory_device *mem_device)
+{
+	acpi_status status;
+	struct acpi_object_list arg_list;
+	union acpi_object arg;
+	unsigned long long current_status;
+
+
+	/* Issue the _EJ0 command */
+	arg_list.count = 1;
+	arg_list.pointer = &arg;
+	arg.type = ACPI_TYPE_INTEGER;
+	arg.integer.value = 1;
+	status = acpi_evaluate_object(mem_device->device->handle,
+				      "_EJ0", &arg_list, NULL);
+	/* Return on _EJ0 failure */
+	if (ACPI_FAILURE(status)) {
+		ACPI_EXCEPTION((AE_INFO, status, "_EJ0 failed"));
+		return -ENODEV;
+	}
+
+	/* Evalute _STA to check if the device is disabled */
+	status = acpi_evaluate_integer(mem_device->device->handle, "_STA",
+				       NULL, &current_status);
+	if (ACPI_FAILURE(status))
+		return -ENODEV;
+
+	/* Check for device status.  Device should be disabled */
+	if (current_status & ACPI_STA_DEVICE_ENABLED)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int acpi_memory_disable_device(struct acpi_memory_device *mem_device)
+{
+	int result;
+	struct acpi_memory_info *info, *n;
+
+
+	/*
+	 * Ask the VM to offline this memory range.
+	 * Note: Assume that this function returns zero on success
+	 */
+	list_for_each_entry_safe(info, n, &mem_device->res_list, list) {
+		if (info->enabled) {
+			result = remove_memory(info->start_addr, info->length);
+			if (result)
+				return result;
+		}
+		kfree(info);
+	}
+
+	/* Power-off and eject the device */
+	result = acpi_memory_powerdown_device(mem_device);
+	if (result) {
+		/* Set the status of the device to invalid */
+		mem_device->state = MEMORY_INVALID_STATE;
+		return result;
+	}
+
+	mem_device->state = MEMORY_POWER_OFF_STATE;
+	return result;
+}
+
+static void acpi_memory_device_notify(acpi_handle handle, u32 event, void *data)
+{
+	struct acpi_memory_device *mem_device;
+	struct acpi_device *device;
+
+
+	switch (event) {
+	case ACPI_NOTIFY_BUS_CHECK:
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+				  "\nReceived BUS CHECK notification for device\n"));
+		/* Fall Through */
+	case ACPI_NOTIFY_DEVICE_CHECK:
+		if (event == ACPI_NOTIFY_DEVICE_CHECK)
+			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+					  "\nReceived DEVICE CHECK notification for device\n"));
+		if (acpi_memory_get_device(handle, &mem_device)) {
+			printk(KERN_ERR PREFIX "Cannot find driver data\n");
+			return;
+		}
+
+		if (!acpi_memory_check_device(mem_device)) {
+			if (acpi_memory_enable_device(mem_device))
+				printk(KERN_ERR PREFIX
+					    "Cannot enable memory device\n");
+		}
+		break;
+	case ACPI_NOTIFY_EJECT_REQUEST:
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+				  "\nReceived EJECT REQUEST notification for device\n"));
+
+		if (acpi_bus_get_device(handle, &device)) {
+			printk(KERN_ERR PREFIX "Device doesn't exist\n");
+			break;
+		}
+		mem_device = acpi_driver_data(device);
+		if (!mem_device) {
+			printk(KERN_ERR PREFIX "Driver Data is NULL\n");
+			break;
+		}
+
+		/*
+		 * Currently disabling memory device from kernel mode
+		 * TBD: Can also be disabled from user mode scripts
+		 * TBD: Can also be disabled by Callback registration
+		 *      with generic sysfs driver
+		 */
+		if (acpi_memory_disable_device(mem_device))
+			printk(KERN_ERR PREFIX
+				    "Disable memory device\n");
+		/*
+		 * TBD: Invoke acpi_bus_remove to cleanup data structures
+		 */
+		break;
+	default:
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+				  "Unsupported event [0x%x]\n", event));
+		break;
+	}
+
+	return;
+}
+
+static int acpi_memory_device_add(struct acpi_device *device)
+{
+	int result;
+	struct acpi_memory_device *mem_device = NULL;
+
+
+	if (!device)
+		return -EINVAL;
+
+	mem_device = kzalloc(sizeof(struct acpi_memory_device), GFP_KERNEL);
+	if (!mem_device)
+		return -ENOMEM;
+
+	INIT_LIST_HEAD(&mem_device->res_list);
+	mem_device->device = device;
+	sprintf(acpi_device_name(device), "%s", ACPI_MEMORY_DEVICE_NAME);
+	sprintf(acpi_device_class(device), "%s", ACPI_MEMORY_DEVICE_CLASS);
+	device->driver_data = mem_device;
+
+	/* Get the range from the _CRS */
+	result = acpi_memory_get_device_resources(mem_device);
+	if (result) {
+		device->driver_data = NULL;
+		kfree(mem_device);
+		return result;
+	}
+
+	/* Set the device state */
+	mem_device->state = MEMORY_POWER_ON_STATE;
+
+	printk(KERN_DEBUG "%s \n", acpi_device_name(device));
+
+	/*
+	 * Early boot code has recognized memory area by EFI/E820.
+	 * If DSDT shows these memory devices on boot, hotplug is not necessary
+	 * for them. So, it just returns until completion of this driver's
+	 * start up.
+	 */
+	if (!acpi_hotmem_initialized)
+		return 0;
+
+	if (!acpi_memory_check_device(mem_device)) {
+		/* call add_memory func */
+		result = acpi_memory_enable_device(mem_device);
+		if (result)
+			printk(KERN_ERR PREFIX
+				"Error in acpi_memory_enable_device\n");
+	}
+	return result;
+}
+
+static int acpi_memory_device_remove(struct acpi_device *device, int type)
+{
+	struct acpi_memory_device *mem_device = NULL;
+
+
+	if (!device || !acpi_driver_data(device))
+		return -EINVAL;
+
+	mem_device = acpi_driver_data(device);
+	kfree(mem_device);
+
+	return 0;
+}
+
+/*
+ * Helper function to check for memory device
+ */
+static acpi_status is_memory_device(acpi_handle handle)
+{
+	char *hardware_id;
+	acpi_status status;
+	struct acpi_device_info *info;
+
+	status = acpi_get_object_info(handle, &info);
+	if (ACPI_FAILURE(status))
+		return status;
+
+	if (!(info->valid & ACPI_VALID_HID)) {
+		kfree(info);
+		return AE_ERROR;
+	}
+
+	hardware_id = info->hardware_id.string;
+	if ((hardware_id == NULL) ||
+	    (strcmp(hardware_id, ACPI_MEMORY_DEVICE_HID)))
+		status = AE_ERROR;
+
+	kfree(info);
+	return status;
+}
+
+static acpi_status
+acpi_memory_register_notify_handler(acpi_handle handle,
+				    u32 level, void *ctxt, void **retv)
+{
+	acpi_status status;
+
+
+	status = is_memory_device(handle);
+	if (ACPI_FAILURE(status))
+		return AE_OK;	/* continue */
+
+	status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
+					     acpi_memory_device_notify, NULL);
+	/* continue */
+	return AE_OK;
+}
+
+static acpi_status
+acpi_memory_deregister_notify_handler(acpi_handle handle,
+				      u32 level, void *ctxt, void **retv)
+{
+	acpi_status status;
+
+
+	status = is_memory_device(handle);
+	if (ACPI_FAILURE(status))
+		return AE_OK;	/* continue */
+
+	status = acpi_remove_notify_handler(handle,
+					    ACPI_SYSTEM_NOTIFY,
+					    acpi_memory_device_notify);
+
+	return AE_OK;	/* continue */
+}
+
+static int __init acpi_memory_device_init(void)
+{
+	int result;
+	acpi_status status;
+
+
+	result = acpi_bus_register_driver(&acpi_memory_device_driver);
+
+	if (result < 0)
+		return -ENODEV;
+
+	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
+				     ACPI_UINT32_MAX,
+				     acpi_memory_register_notify_handler, NULL,
+				     NULL, NULL);
+
+	if (ACPI_FAILURE(status)) {
+		ACPI_EXCEPTION((AE_INFO, status, "walk_namespace failed"));
+		acpi_bus_unregister_driver(&acpi_memory_device_driver);
+		return -ENODEV;
+	}
+
+	acpi_hotmem_initialized = 1;
+	return 0;
+}
+
+static void __exit acpi_memory_device_exit(void)
+{
+	acpi_status status;
+
+
+	/*
+	 * Adding this to un-install notification handlers for all the device
+	 * handles.
+	 */
+	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
+				     ACPI_UINT32_MAX,
+				     acpi_memory_deregister_notify_handler, NULL,
+				     NULL, NULL);
+
+	if (ACPI_FAILURE(status))
+		ACPI_EXCEPTION((AE_INFO, status, "walk_namespace failed"));
+
+	acpi_bus_unregister_driver(&acpi_memory_device_driver);
+
+	return;
+}
+
+module_init(acpi_memory_device_init);
+module_exit(acpi_memory_device_exit);