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 int pseries_remove_memblock(unsigned long base, unsigned int memblock_size)
22 unsigned long start, start_pfn;
26 start_pfn = base >> PAGE_SHIFT;
28 if (!pfn_valid(start_pfn)) {
29 memblock_remove(base, memblock_size);
33 zone = page_zone(pfn_to_page(start_pfn));
36 * Remove section mappings and sysfs entries for the
37 * section of the memory we are removing.
39 * NOTE: Ideally, this should be done in generic code like
40 * remove_memory(). But remove_memory() gets called by writing
41 * to sysfs "state" file and we can't remove sysfs entries
42 * while writing to it. So we have to defer it to here.
44 ret = __remove_pages(zone, start_pfn, memblock_size >> PAGE_SHIFT);
49 * Update memory regions for memory remove
51 memblock_remove(base, memblock_size);
54 * Remove htab bolted mappings for this section of memory
56 start = (unsigned long)__va(base);
57 ret = remove_section_mapping(start, start + memblock_size);
59 /* Ensure all vmalloc mappings are flushed in case they also
60 * hit that section of memory
67 static int pseries_remove_memory(struct device_node *np)
70 const unsigned int *regs;
72 unsigned int lmb_size;
76 * Check to see if we are actually removing memory
78 type = of_get_property(np, "device_type", NULL);
79 if (type == NULL || strcmp(type, "memory") != 0)
83 * Find the bae address and size of the memblock
85 regs = of_get_property(np, "reg", NULL);
89 base = *(unsigned long *)regs;
92 ret = pseries_remove_memblock(base, lmb_size);
96 static int pseries_add_memory(struct device_node *np)
99 const unsigned int *regs;
101 unsigned int lmb_size;
105 * Check to see if we are actually adding memory
107 type = of_get_property(np, "device_type", NULL);
108 if (type == NULL || strcmp(type, "memory") != 0)
112 * Find the base and size of the memblock
114 regs = of_get_property(np, "reg", NULL);
118 base = *(unsigned long *)regs;
122 * Update memory region to represent the memory add
124 ret = memblock_add(base, lmb_size);
125 return (ret < 0) ? -EINVAL : 0;
128 static int pseries_drconf_memory(unsigned long *base, unsigned int action)
130 struct device_node *np;
131 const unsigned long *lmb_size;
134 np = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
138 lmb_size = of_get_property(np, "ibm,lmb-size", NULL);
144 if (action == PSERIES_DRCONF_MEM_ADD) {
145 rc = memblock_add(*base, *lmb_size);
146 rc = (rc < 0) ? -EINVAL : 0;
147 } else if (action == PSERIES_DRCONF_MEM_REMOVE) {
148 rc = pseries_remove_memblock(*base, *lmb_size);
157 static int pseries_memory_notifier(struct notifier_block *nb,
158 unsigned long action, void *node)
163 case PSERIES_RECONFIG_ADD:
164 if (pseries_add_memory(node))
167 case PSERIES_RECONFIG_REMOVE:
168 if (pseries_remove_memory(node))
171 case PSERIES_DRCONF_MEM_ADD:
172 case PSERIES_DRCONF_MEM_REMOVE:
173 if (pseries_drconf_memory(node, action))
183 static struct notifier_block pseries_mem_nb = {
184 .notifier_call = pseries_memory_notifier,
187 static int __init pseries_memory_hotplug_init(void)
189 if (firmware_has_feature(FW_FEATURE_LPAR))
190 pSeries_reconfig_notifier_register(&pseries_mem_nb);
194 machine_device_initcall(pseries, pseries_memory_hotplug_init);