2 * pseries Memory Hotplug infrastructure.
4 * Copyright (C) 2008 Badari Pulavarty, IBM Corporation
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
13 #include <linux/memblock.h>
14 #include <linux/vmalloc.h>
15 #include <asm/firmware.h>
16 #include <asm/machdep.h>
17 #include <asm/pSeries_reconfig.h>
18 #include <asm/sparsemem.h>
20 static unsigned long get_memblock_size(void)
22 struct device_node *np;
23 unsigned int memblock_size = 0;
25 np = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
27 const unsigned long *size;
29 size = of_get_property(np, "ibm,lmb-size", NULL);
30 memblock_size = size ? *size : 0;
34 unsigned int memzero_size = 0;
35 const unsigned int *regs;
37 np = of_find_node_by_path("/memory@0");
39 regs = of_get_property(np, "reg", NULL);
40 memzero_size = regs ? regs[3] : 0;
45 /* We now know the size of memory@0, use this to find
46 * the first memoryblock and get its size.
50 sprintf(buf, "/memory@%x", memzero_size);
51 np = of_find_node_by_path(buf);
53 regs = of_get_property(np, "reg", NULL);
54 memblock_size = regs ? regs[3] : 0;
63 unsigned long memory_block_size_bytes(void)
65 return get_memblock_size();
68 static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size)
70 unsigned long start, start_pfn;
74 start_pfn = base >> PAGE_SHIFT;
76 if (!pfn_valid(start_pfn)) {
77 memblock_remove(base, memblock_size);
81 zone = page_zone(pfn_to_page(start_pfn));
84 * Remove section mappings and sysfs entries for the
85 * section of the memory we are removing.
87 * NOTE: Ideally, this should be done in generic code like
88 * remove_memory(). But remove_memory() gets called by writing
89 * to sysfs "state" file and we can't remove sysfs entries
90 * while writing to it. So we have to defer it to here.
92 ret = __remove_pages(zone, start_pfn, memblock_size >> PAGE_SHIFT);
97 * Update memory regions for memory remove
99 memblock_remove(base, memblock_size);
102 * Remove htab bolted mappings for this section of memory
104 start = (unsigned long)__va(base);
105 ret = remove_section_mapping(start, start + memblock_size);
107 /* Ensure all vmalloc mappings are flushed in case they also
108 * hit that section of memory
115 static int pseries_remove_memory(struct device_node *np)
118 const unsigned int *regs;
120 unsigned int lmb_size;
124 * Check to see if we are actually removing memory
126 type = of_get_property(np, "device_type", NULL);
127 if (type == NULL || strcmp(type, "memory") != 0)
131 * Find the bae address and size of the memblock
133 regs = of_get_property(np, "reg", NULL);
137 base = *(unsigned long *)regs;
140 ret = pseries_remove_memblock(base, lmb_size);
144 static int pseries_add_memory(struct device_node *np)
147 const unsigned int *regs;
149 unsigned int lmb_size;
153 * Check to see if we are actually adding memory
155 type = of_get_property(np, "device_type", NULL);
156 if (type == NULL || strcmp(type, "memory") != 0)
160 * Find the base and size of the memblock
162 regs = of_get_property(np, "reg", NULL);
166 base = *(unsigned long *)regs;
170 * Update memory region to represent the memory add
172 ret = memblock_add(base, lmb_size);
173 return (ret < 0) ? -EINVAL : 0;
176 static int pseries_drconf_memory(unsigned long *base, unsigned int action)
178 unsigned long memblock_size;
181 memblock_size = get_memblock_size();
185 if (action == PSERIES_DRCONF_MEM_ADD) {
186 rc = memblock_add(*base, memblock_size);
187 rc = (rc < 0) ? -EINVAL : 0;
188 } else if (action == PSERIES_DRCONF_MEM_REMOVE) {
189 rc = pseries_remove_memblock(*base, memblock_size);
197 static int pseries_memory_notifier(struct notifier_block *nb,
198 unsigned long action, void *node)
203 case PSERIES_RECONFIG_ADD:
204 if (pseries_add_memory(node))
207 case PSERIES_RECONFIG_REMOVE:
208 if (pseries_remove_memory(node))
211 case PSERIES_DRCONF_MEM_ADD:
212 case PSERIES_DRCONF_MEM_REMOVE:
213 if (pseries_drconf_memory(node, action))
223 static struct notifier_block pseries_mem_nb = {
224 .notifier_call = pseries_memory_notifier,
227 static int __init pseries_memory_hotplug_init(void)
229 if (firmware_has_feature(FW_FEATURE_LPAR))
230 pSeries_reconfig_notifier_register(&pseries_mem_nb);
234 machine_device_initcall(pseries, pseries_memory_hotplug_init);