2  * nvs.c - Routines for saving and restoring ACPI NVS memory region
4  * Copyright (C) 2008-2011 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
39 	struct nvs_region *region;  in acpi_nvs_register()  local
41 	region = kmalloc(sizeof(*region), GFP_KERNEL);  in acpi_nvs_register()
42 	if (!region)  in acpi_nvs_register()
43 		return -ENOMEM;  in acpi_nvs_register()
44 	region->phys_start = start;  in acpi_nvs_register()
45 	region->size = size;  in acpi_nvs_register()
46 	list_add_tail(&region->node, &nvs_region_list);  in acpi_nvs_register()
55 	struct nvs_region *region;  in acpi_nvs_for_each_region()  local
57 	list_for_each_entry(region, &nvs_region_list, node) {  in acpi_nvs_for_each_region()
58 		rc = func(region->phys_start, region->size, data);  in acpi_nvs_for_each_region()
69  * Platforms, like ACPI, may want us to save some memory used by them during
70  * suspend and to restore the contents of this memory during the subsequent
86  *	suspend_nvs_register - register platform NVS memory region to save
87  *	@start - physical address of the region
88  *	@size - size of the region
90  *	The NVS region need not be page-aligned (both ends) and we arrange
91  *	things so that the data from page-aligned addresses in this region will
98 	pr_info("PM: Registering ACPI NVS region [mem %#010lx-%#010lx] (%ld bytes)\n",  in suspend_nvs_register()
99 		start, start + size - 1, size);  in suspend_nvs_register()
108 		list_add_tail(&entry->node, &nvs_list);  in suspend_nvs_register()
109 		entry->phys_start = start;  in suspend_nvs_register()
110 		nr_bytes = PAGE_SIZE - (start & ~PAGE_MASK);  in suspend_nvs_register()
111 		entry->size = (size < nr_bytes) ? size : nr_bytes;  in suspend_nvs_register()
113 		start += entry->size;  in suspend_nvs_register()
114 		size -= entry->size;  in suspend_nvs_register()
120 		list_del(&entry->node);  in suspend_nvs_register()
123 	return -ENOMEM;  in suspend_nvs_register()
127  *	suspend_nvs_free - free data pages allocated for saving NVS regions
134 		if (entry->data) {  in suspend_nvs_free()
135 			free_page((unsigned long)entry->data);  in suspend_nvs_free()
136 			entry->data = NULL;  in suspend_nvs_free()
137 			if (entry->kaddr) {  in suspend_nvs_free()
138 				if (entry->unmap) {  in suspend_nvs_free()
139 					iounmap(entry->kaddr);  in suspend_nvs_free()
140 					entry->unmap = false;  in suspend_nvs_free()
142 					acpi_os_unmap_iomem(entry->kaddr,  in suspend_nvs_free()
143 							    entry->size);  in suspend_nvs_free()
145 				entry->kaddr = NULL;  in suspend_nvs_free()
151  *	suspend_nvs_alloc - allocate memory necessary for saving NVS regions
158 		entry->data = (void *)__get_free_page(GFP_KERNEL);  in suspend_nvs_alloc()
159 		if (!entry->data) {  in suspend_nvs_alloc()
161 			return -ENOMEM;  in suspend_nvs_alloc()
168  *	suspend_nvs_save - save NVS memory regions
174 	printk(KERN_INFO "PM: Saving platform NVS memory\n");  in suspend_nvs_save()
177 		if (entry->data) {  in suspend_nvs_save()
178 			unsigned long phys = entry->phys_start;  in suspend_nvs_save()
179 			unsigned int size = entry->size;  in suspend_nvs_save()
181 			entry->kaddr = acpi_os_get_iomem(phys, size);  in suspend_nvs_save()
182 			if (!entry->kaddr) {  in suspend_nvs_save()
183 				entry->kaddr = acpi_os_ioremap(phys, size);  in suspend_nvs_save()
184 				entry->unmap = !!entry->kaddr;  in suspend_nvs_save()
186 			if (!entry->kaddr) {  in suspend_nvs_save()
188 				return -ENOMEM;  in suspend_nvs_save()
190 			memcpy(entry->data, entry->kaddr, entry->size);  in suspend_nvs_save()
197  *	suspend_nvs_restore - restore NVS memory regions
200  *	cannot iounmap the virtual addresses used to access the NVS region.
206 	printk(KERN_INFO "PM: Restoring platform NVS memory\n");  in suspend_nvs_restore()
209 		if (entry->data)  in suspend_nvs_restore()
210 			memcpy(entry->kaddr, entry->data, entry->size);  in suspend_nvs_restore()