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 static unsigned long get_memblock_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 /* WARNING: This is going to override the generic definition whenever 68 * pseries is built-in regardless of what platform is active at boot 69 * time. This is fine for now as this is the only "option" and it 70 * should work everywhere. If not, we'll have to turn this into a 71 * ppc_md. callback 72 */ 73 unsigned long memory_block_size_bytes(void) 74 { 75 return get_memblock_size(); 76 } 77 78 #ifdef CONFIG_MEMORY_HOTREMOVE 79 static int pseries_remove_memory(u64 start, u64 size) 80 { 81 int ret; 82 83 /* Remove htab bolted mappings for this section of memory */ 84 start = (unsigned long)__va(start); 85 ret = remove_section_mapping(start, start + size); 86 87 /* Ensure all vmalloc mappings are flushed in case they also 88 * hit that section of memory 89 */ 90 vm_unmap_aliases(); 91 92 return ret; 93 } 94 95 static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size) 96 { 97 unsigned long block_sz, start_pfn; 98 int sections_per_block; 99 int i, nid; 100 101 start_pfn = base >> PAGE_SHIFT; 102 103 lock_device_hotplug(); 104 105 if (!pfn_valid(start_pfn)) 106 goto out; 107 108 block_sz = memory_block_size_bytes(); 109 sections_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE; 110 nid = memory_add_physaddr_to_nid(base); 111 112 for (i = 0; i < sections_per_block; i++) { 113 remove_memory(nid, base, MIN_MEMORY_BLOCK_SIZE); 114 base += MIN_MEMORY_BLOCK_SIZE; 115 } 116 117 out: 118 /* Update memory regions for memory remove */ 119 memblock_remove(base, memblock_size); 120 unlock_device_hotplug(); 121 return 0; 122 } 123 124 static int pseries_remove_mem_node(struct device_node *np) 125 { 126 const char *type; 127 const unsigned int *regs; 128 unsigned long base; 129 unsigned int lmb_size; 130 int ret = -EINVAL; 131 132 /* 133 * Check to see if we are actually removing memory 134 */ 135 type = of_get_property(np, "device_type", NULL); 136 if (type == NULL || strcmp(type, "memory") != 0) 137 return 0; 138 139 /* 140 * Find the bae address and size of the memblock 141 */ 142 regs = of_get_property(np, "reg", NULL); 143 if (!regs) 144 return ret; 145 146 base = *(unsigned long *)regs; 147 lmb_size = regs[3]; 148 149 pseries_remove_memblock(base, lmb_size); 150 return 0; 151 } 152 #else 153 static inline int pseries_remove_memblock(unsigned long base, 154 unsigned int memblock_size) 155 { 156 return -EOPNOTSUPP; 157 } 158 static inline int pseries_remove_mem_node(struct device_node *np) 159 { 160 return -EOPNOTSUPP; 161 } 162 #endif /* CONFIG_MEMORY_HOTREMOVE */ 163 164 static int pseries_add_mem_node(struct device_node *np) 165 { 166 const char *type; 167 const unsigned int *regs; 168 unsigned long base; 169 unsigned int lmb_size; 170 int ret = -EINVAL; 171 172 /* 173 * Check to see if we are actually adding memory 174 */ 175 type = of_get_property(np, "device_type", NULL); 176 if (type == NULL || strcmp(type, "memory") != 0) 177 return 0; 178 179 /* 180 * Find the base and size of the memblock 181 */ 182 regs = of_get_property(np, "reg", NULL); 183 if (!regs) 184 return ret; 185 186 base = *(unsigned long *)regs; 187 lmb_size = regs[3]; 188 189 /* 190 * Update memory region to represent the memory add 191 */ 192 ret = memblock_add(base, lmb_size); 193 return (ret < 0) ? -EINVAL : 0; 194 } 195 196 static int pseries_update_drconf_memory(struct of_prop_reconfig *pr) 197 { 198 struct of_drconf_cell *new_drmem, *old_drmem; 199 unsigned long memblock_size; 200 u32 entries; 201 u32 *p; 202 int i, rc = -EINVAL; 203 204 memblock_size = get_memblock_size(); 205 if (!memblock_size) 206 return -EINVAL; 207 208 p = (u32 *)of_get_property(pr->dn, "ibm,dynamic-memory", NULL); 209 if (!p) 210 return -EINVAL; 211 212 /* The first int of the property is the number of lmb's described 213 * by the property. This is followed by an array of of_drconf_cell 214 * entries. Get the niumber of entries and skip to the array of 215 * of_drconf_cell's. 216 */ 217 entries = *p++; 218 old_drmem = (struct of_drconf_cell *)p; 219 220 p = (u32 *)pr->prop->value; 221 p++; 222 new_drmem = (struct of_drconf_cell *)p; 223 224 for (i = 0; i < entries; i++) { 225 if ((old_drmem[i].flags & DRCONF_MEM_ASSIGNED) && 226 (!(new_drmem[i].flags & DRCONF_MEM_ASSIGNED))) { 227 rc = pseries_remove_memblock(old_drmem[i].base_addr, 228 memblock_size); 229 break; 230 } else if ((!(old_drmem[i].flags & DRCONF_MEM_ASSIGNED)) && 231 (new_drmem[i].flags & DRCONF_MEM_ASSIGNED)) { 232 rc = memblock_add(old_drmem[i].base_addr, 233 memblock_size); 234 rc = (rc < 0) ? -EINVAL : 0; 235 break; 236 } 237 } 238 239 return rc; 240 } 241 242 static int pseries_memory_notifier(struct notifier_block *nb, 243 unsigned long action, void *node) 244 { 245 struct of_prop_reconfig *pr; 246 int err = 0; 247 248 switch (action) { 249 case OF_RECONFIG_ATTACH_NODE: 250 err = pseries_add_mem_node(node); 251 break; 252 case OF_RECONFIG_DETACH_NODE: 253 err = pseries_remove_mem_node(node); 254 break; 255 case OF_RECONFIG_UPDATE_PROPERTY: 256 pr = (struct of_prop_reconfig *)node; 257 if (!strcmp(pr->prop->name, "ibm,dynamic-memory")) 258 err = pseries_update_drconf_memory(pr); 259 break; 260 } 261 return notifier_from_errno(err); 262 } 263 264 static struct notifier_block pseries_mem_nb = { 265 .notifier_call = pseries_memory_notifier, 266 }; 267 268 static int __init pseries_memory_hotplug_init(void) 269 { 270 if (firmware_has_feature(FW_FEATURE_LPAR)) 271 of_reconfig_notifier_register(&pseries_mem_nb); 272 273 #ifdef CONFIG_MEMORY_HOTREMOVE 274 ppc_md.remove_memory = pseries_remove_memory; 275 #endif 276 277 return 0; 278 } 279 machine_device_initcall(pseries, pseries_memory_hotplug_init); 280