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 #include "pseries.h" 24 25 unsigned long pseries_memory_block_size(void) 26 { 27 struct device_node *np; 28 unsigned int memblock_size = MIN_MEMORY_BLOCK_SIZE; 29 struct resource r; 30 31 np = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory"); 32 if (np) { 33 const __be64 *size; 34 35 size = of_get_property(np, "ibm,lmb-size", NULL); 36 if (size) 37 memblock_size = be64_to_cpup(size); 38 of_node_put(np); 39 } else if (machine_is(pseries)) { 40 /* This fallback really only applies to pseries */ 41 unsigned int memzero_size = 0; 42 43 np = of_find_node_by_path("/memory@0"); 44 if (np) { 45 if (!of_address_to_resource(np, 0, &r)) 46 memzero_size = resource_size(&r); 47 of_node_put(np); 48 } 49 50 if (memzero_size) { 51 /* We now know the size of memory@0, use this to find 52 * the first memoryblock and get its size. 53 */ 54 char buf[64]; 55 56 sprintf(buf, "/memory@%x", memzero_size); 57 np = of_find_node_by_path(buf); 58 if (np) { 59 if (!of_address_to_resource(np, 0, &r)) 60 memblock_size = resource_size(&r); 61 of_node_put(np); 62 } 63 } 64 } 65 return memblock_size; 66 } 67 68 #ifdef CONFIG_MEMORY_HOTREMOVE 69 static int pseries_remove_memory(u64 start, u64 size) 70 { 71 int ret; 72 73 /* Remove htab bolted mappings for this section of memory */ 74 start = (unsigned long)__va(start); 75 ret = remove_section_mapping(start, start + size); 76 77 /* Ensure all vmalloc mappings are flushed in case they also 78 * hit that section of memory 79 */ 80 vm_unmap_aliases(); 81 82 return ret; 83 } 84 85 static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size) 86 { 87 unsigned long block_sz, start_pfn; 88 int sections_per_block; 89 int i, nid; 90 91 start_pfn = base >> PAGE_SHIFT; 92 93 lock_device_hotplug(); 94 95 if (!pfn_valid(start_pfn)) 96 goto out; 97 98 block_sz = pseries_memory_block_size(); 99 sections_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE; 100 nid = memory_add_physaddr_to_nid(base); 101 102 for (i = 0; i < sections_per_block; i++) { 103 remove_memory(nid, base, MIN_MEMORY_BLOCK_SIZE); 104 base += MIN_MEMORY_BLOCK_SIZE; 105 } 106 107 out: 108 /* Update memory regions for memory remove */ 109 memblock_remove(base, memblock_size); 110 unlock_device_hotplug(); 111 return 0; 112 } 113 114 static int pseries_remove_mem_node(struct device_node *np) 115 { 116 const char *type; 117 const __be32 *regs; 118 unsigned long base; 119 unsigned int lmb_size; 120 int ret = -EINVAL; 121 122 /* 123 * Check to see if we are actually removing memory 124 */ 125 type = of_get_property(np, "device_type", NULL); 126 if (type == NULL || strcmp(type, "memory") != 0) 127 return 0; 128 129 /* 130 * Find the base address and size of the memblock 131 */ 132 regs = of_get_property(np, "reg", NULL); 133 if (!regs) 134 return ret; 135 136 base = be64_to_cpu(*(unsigned long *)regs); 137 lmb_size = be32_to_cpu(regs[3]); 138 139 pseries_remove_memblock(base, lmb_size); 140 return 0; 141 } 142 #else 143 static inline int pseries_remove_memblock(unsigned long base, 144 unsigned int memblock_size) 145 { 146 return -EOPNOTSUPP; 147 } 148 static inline int pseries_remove_mem_node(struct device_node *np) 149 { 150 return 0; 151 } 152 #endif /* CONFIG_MEMORY_HOTREMOVE */ 153 154 static int pseries_add_mem_node(struct device_node *np) 155 { 156 const char *type; 157 const __be32 *regs; 158 unsigned long base; 159 unsigned int lmb_size; 160 int ret = -EINVAL; 161 162 /* 163 * Check to see if we are actually adding memory 164 */ 165 type = of_get_property(np, "device_type", NULL); 166 if (type == NULL || strcmp(type, "memory") != 0) 167 return 0; 168 169 /* 170 * Find the base and size of the memblock 171 */ 172 regs = of_get_property(np, "reg", NULL); 173 if (!regs) 174 return ret; 175 176 base = be64_to_cpu(*(unsigned long *)regs); 177 lmb_size = be32_to_cpu(regs[3]); 178 179 /* 180 * Update memory region to represent the memory add 181 */ 182 ret = memblock_add(base, lmb_size); 183 return (ret < 0) ? -EINVAL : 0; 184 } 185 186 static int pseries_update_drconf_memory(struct of_prop_reconfig *pr) 187 { 188 struct of_drconf_cell *new_drmem, *old_drmem; 189 unsigned long memblock_size; 190 u32 entries; 191 __be32 *p; 192 int i, rc = -EINVAL; 193 194 memblock_size = pseries_memory_block_size(); 195 if (!memblock_size) 196 return -EINVAL; 197 198 p = (__be32 *) pr->old_prop->value; 199 if (!p) 200 return -EINVAL; 201 202 /* The first int of the property is the number of lmb's described 203 * by the property. This is followed by an array of of_drconf_cell 204 * entries. Get the number of entries and skip to the array of 205 * of_drconf_cell's. 206 */ 207 entries = be32_to_cpu(*p++); 208 old_drmem = (struct of_drconf_cell *)p; 209 210 p = (__be32 *)pr->prop->value; 211 p++; 212 new_drmem = (struct of_drconf_cell *)p; 213 214 for (i = 0; i < entries; i++) { 215 if ((be32_to_cpu(old_drmem[i].flags) & DRCONF_MEM_ASSIGNED) && 216 (!(be32_to_cpu(new_drmem[i].flags) & DRCONF_MEM_ASSIGNED))) { 217 rc = pseries_remove_memblock( 218 be64_to_cpu(old_drmem[i].base_addr), 219 memblock_size); 220 break; 221 } else if ((!(be32_to_cpu(old_drmem[i].flags) & 222 DRCONF_MEM_ASSIGNED)) && 223 (be32_to_cpu(new_drmem[i].flags) & 224 DRCONF_MEM_ASSIGNED)) { 225 rc = memblock_add(be64_to_cpu(old_drmem[i].base_addr), 226 memblock_size); 227 rc = (rc < 0) ? -EINVAL : 0; 228 break; 229 } 230 } 231 return rc; 232 } 233 234 static int pseries_memory_notifier(struct notifier_block *nb, 235 unsigned long action, void *node) 236 { 237 struct of_prop_reconfig *pr; 238 int err = 0; 239 240 switch (action) { 241 case OF_RECONFIG_ATTACH_NODE: 242 err = pseries_add_mem_node(node); 243 break; 244 case OF_RECONFIG_DETACH_NODE: 245 err = pseries_remove_mem_node(node); 246 break; 247 case OF_RECONFIG_UPDATE_PROPERTY: 248 pr = (struct of_prop_reconfig *)node; 249 if (!strcmp(pr->prop->name, "ibm,dynamic-memory")) 250 err = pseries_update_drconf_memory(pr); 251 break; 252 } 253 return notifier_from_errno(err); 254 } 255 256 static struct notifier_block pseries_mem_nb = { 257 .notifier_call = pseries_memory_notifier, 258 }; 259 260 static int __init pseries_memory_hotplug_init(void) 261 { 262 if (firmware_has_feature(FW_FEATURE_LPAR)) 263 of_reconfig_notifier_register(&pseries_mem_nb); 264 265 #ifdef CONFIG_MEMORY_HOTREMOVE 266 ppc_md.remove_memory = pseries_remove_memory; 267 #endif 268 269 return 0; 270 } 271 machine_device_initcall(pseries, pseries_memory_hotplug_init); 272