1 /* 2 * pseries Memory Hotplug infrastructure. 3 * 4 * Copyright (C) 2008 Badari Pulavarty, IBM Corporation 5 * 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. 10 */ 11 12 #include <linux/of.h> 13 #include <linux/of_address.h> 14 #include <linux/memblock.h> 15 #include <linux/vmalloc.h> 16 #include <linux/memory.h> 17 #include <linux/memory_hotplug.h> 18 19 #include <asm/firmware.h> 20 #include <asm/machdep.h> 21 #include <asm/prom.h> 22 #include <asm/sparsemem.h> 23 24 unsigned long pseries_memory_block_size(void) 25 { 26 struct device_node *np; 27 unsigned int memblock_size = MIN_MEMORY_BLOCK_SIZE; 28 struct resource r; 29 30 np = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory"); 31 if (np) { 32 const __be64 *size; 33 34 size = of_get_property(np, "ibm,lmb-size", NULL); 35 if (size) 36 memblock_size = be64_to_cpup(size); 37 of_node_put(np); 38 } else if (machine_is(pseries)) { 39 /* This fallback really only applies to pseries */ 40 unsigned int memzero_size = 0; 41 42 np = of_find_node_by_path("/memory@0"); 43 if (np) { 44 if (!of_address_to_resource(np, 0, &r)) 45 memzero_size = resource_size(&r); 46 of_node_put(np); 47 } 48 49 if (memzero_size) { 50 /* We now know the size of memory@0, use this to find 51 * the first memoryblock and get its size. 52 */ 53 char buf[64]; 54 55 sprintf(buf, "/memory@%x", memzero_size); 56 np = of_find_node_by_path(buf); 57 if (np) { 58 if (!of_address_to_resource(np, 0, &r)) 59 memblock_size = resource_size(&r); 60 of_node_put(np); 61 } 62 } 63 } 64 return memblock_size; 65 } 66 67 #ifdef CONFIG_MEMORY_HOTREMOVE 68 static int pseries_remove_memory(u64 start, u64 size) 69 { 70 int ret; 71 72 /* Remove htab bolted mappings for this section of memory */ 73 start = (unsigned long)__va(start); 74 ret = remove_section_mapping(start, start + size); 75 76 /* Ensure all vmalloc mappings are flushed in case they also 77 * hit that section of memory 78 */ 79 vm_unmap_aliases(); 80 81 return ret; 82 } 83 84 static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size) 85 { 86 unsigned long block_sz, start_pfn; 87 int sections_per_block; 88 int i, nid; 89 90 start_pfn = base >> PAGE_SHIFT; 91 92 lock_device_hotplug(); 93 94 if (!pfn_valid(start_pfn)) 95 goto out; 96 97 block_sz = pseries_memory_block_size(); 98 sections_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE; 99 nid = memory_add_physaddr_to_nid(base); 100 101 for (i = 0; i < sections_per_block; i++) { 102 remove_memory(nid, base, MIN_MEMORY_BLOCK_SIZE); 103 base += MIN_MEMORY_BLOCK_SIZE; 104 } 105 106 out: 107 /* Update memory regions for memory remove */ 108 memblock_remove(base, memblock_size); 109 unlock_device_hotplug(); 110 return 0; 111 } 112 113 static int pseries_remove_mem_node(struct device_node *np) 114 { 115 const char *type; 116 const unsigned int *regs; 117 unsigned long base; 118 unsigned int lmb_size; 119 int ret = -EINVAL; 120 121 /* 122 * Check to see if we are actually removing memory 123 */ 124 type = of_get_property(np, "device_type", NULL); 125 if (type == NULL || strcmp(type, "memory") != 0) 126 return 0; 127 128 /* 129 * Find the bae address and size of the memblock 130 */ 131 regs = of_get_property(np, "reg", NULL); 132 if (!regs) 133 return ret; 134 135 base = *(unsigned long *)regs; 136 lmb_size = regs[3]; 137 138 pseries_remove_memblock(base, lmb_size); 139 return 0; 140 } 141 #else 142 static inline int pseries_remove_memblock(unsigned long base, 143 unsigned int memblock_size) 144 { 145 return -EOPNOTSUPP; 146 } 147 static inline int pseries_remove_mem_node(struct device_node *np) 148 { 149 return -EOPNOTSUPP; 150 } 151 #endif /* CONFIG_MEMORY_HOTREMOVE */ 152 153 static int pseries_add_mem_node(struct device_node *np) 154 { 155 const char *type; 156 const unsigned int *regs; 157 unsigned long base; 158 unsigned int lmb_size; 159 int ret = -EINVAL; 160 161 /* 162 * Check to see if we are actually adding memory 163 */ 164 type = of_get_property(np, "device_type", NULL); 165 if (type == NULL || strcmp(type, "memory") != 0) 166 return 0; 167 168 /* 169 * Find the base and size of the memblock 170 */ 171 regs = of_get_property(np, "reg", NULL); 172 if (!regs) 173 return ret; 174 175 base = *(unsigned long *)regs; 176 lmb_size = regs[3]; 177 178 /* 179 * Update memory region to represent the memory add 180 */ 181 ret = memblock_add(base, lmb_size); 182 return (ret < 0) ? -EINVAL : 0; 183 } 184 185 static int pseries_update_drconf_memory(struct of_prop_reconfig *pr) 186 { 187 struct of_drconf_cell *new_drmem, *old_drmem; 188 unsigned long memblock_size; 189 u32 entries; 190 u32 *p; 191 int i, rc = -EINVAL; 192 193 memblock_size = pseries_memory_block_size(); 194 if (!memblock_size) 195 return -EINVAL; 196 197 p = (u32 *)of_get_property(pr->dn, "ibm,dynamic-memory", NULL); 198 if (!p) 199 return -EINVAL; 200 201 /* The first int of the property is the number of lmb's described 202 * by the property. This is followed by an array of of_drconf_cell 203 * entries. Get the niumber of entries and skip to the array of 204 * of_drconf_cell's. 205 */ 206 entries = *p++; 207 old_drmem = (struct of_drconf_cell *)p; 208 209 p = (u32 *)pr->prop->value; 210 p++; 211 new_drmem = (struct of_drconf_cell *)p; 212 213 for (i = 0; i < entries; i++) { 214 if ((old_drmem[i].flags & DRCONF_MEM_ASSIGNED) && 215 (!(new_drmem[i].flags & DRCONF_MEM_ASSIGNED))) { 216 rc = pseries_remove_memblock(old_drmem[i].base_addr, 217 memblock_size); 218 break; 219 } else if ((!(old_drmem[i].flags & DRCONF_MEM_ASSIGNED)) && 220 (new_drmem[i].flags & DRCONF_MEM_ASSIGNED)) { 221 rc = memblock_add(old_drmem[i].base_addr, 222 memblock_size); 223 rc = (rc < 0) ? -EINVAL : 0; 224 break; 225 } 226 } 227 228 return rc; 229 } 230 231 static int pseries_memory_notifier(struct notifier_block *nb, 232 unsigned long action, void *node) 233 { 234 struct of_prop_reconfig *pr; 235 int err = 0; 236 237 switch (action) { 238 case OF_RECONFIG_ATTACH_NODE: 239 err = pseries_add_mem_node(node); 240 break; 241 case OF_RECONFIG_DETACH_NODE: 242 err = pseries_remove_mem_node(node); 243 break; 244 case OF_RECONFIG_UPDATE_PROPERTY: 245 pr = (struct of_prop_reconfig *)node; 246 if (!strcmp(pr->prop->name, "ibm,dynamic-memory")) 247 err = pseries_update_drconf_memory(pr); 248 break; 249 } 250 return notifier_from_errno(err); 251 } 252 253 static struct notifier_block pseries_mem_nb = { 254 .notifier_call = pseries_memory_notifier, 255 }; 256 257 static int __init pseries_memory_hotplug_init(void) 258 { 259 if (firmware_has_feature(FW_FEATURE_LPAR)) 260 of_reconfig_notifier_register(&pseries_mem_nb); 261 262 #ifdef CONFIG_MEMORY_HOTREMOVE 263 ppc_md.remove_memory = pseries_remove_memory; 264 #endif 265 266 return 0; 267 } 268 machine_device_initcall(pseries, pseries_memory_hotplug_init); 269