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/memory.h> 16 #include <linux/memory_hotplug.h> 17 18 #include <asm/firmware.h> 19 #include <asm/machdep.h> 20 #include <asm/prom.h> 21 #include <asm/sparsemem.h> 22 #include "pseries.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_memblock(unsigned long base, unsigned int memblock_size) 69 { 70 unsigned long block_sz, start_pfn; 71 int sections_per_block; 72 int i, nid; 73 74 start_pfn = base >> PAGE_SHIFT; 75 76 lock_device_hotplug(); 77 78 if (!pfn_valid(start_pfn)) 79 goto out; 80 81 block_sz = pseries_memory_block_size(); 82 sections_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE; 83 nid = memory_add_physaddr_to_nid(base); 84 85 for (i = 0; i < sections_per_block; i++) { 86 remove_memory(nid, base, MIN_MEMORY_BLOCK_SIZE); 87 base += MIN_MEMORY_BLOCK_SIZE; 88 } 89 90 out: 91 /* Update memory regions for memory remove */ 92 memblock_remove(base, memblock_size); 93 unlock_device_hotplug(); 94 return 0; 95 } 96 97 static int pseries_remove_mem_node(struct device_node *np) 98 { 99 const char *type; 100 const __be32 *regs; 101 unsigned long base; 102 unsigned int lmb_size; 103 int ret = -EINVAL; 104 105 /* 106 * Check to see if we are actually removing memory 107 */ 108 type = of_get_property(np, "device_type", NULL); 109 if (type == NULL || strcmp(type, "memory") != 0) 110 return 0; 111 112 /* 113 * Find the base address and size of the memblock 114 */ 115 regs = of_get_property(np, "reg", NULL); 116 if (!regs) 117 return ret; 118 119 base = be64_to_cpu(*(unsigned long *)regs); 120 lmb_size = be32_to_cpu(regs[3]); 121 122 pseries_remove_memblock(base, lmb_size); 123 return 0; 124 } 125 #else 126 static inline int pseries_remove_memblock(unsigned long base, 127 unsigned int memblock_size) 128 { 129 return -EOPNOTSUPP; 130 } 131 static inline int pseries_remove_mem_node(struct device_node *np) 132 { 133 return 0; 134 } 135 #endif /* CONFIG_MEMORY_HOTREMOVE */ 136 137 static int pseries_add_mem_node(struct device_node *np) 138 { 139 const char *type; 140 const __be32 *regs; 141 unsigned long base; 142 unsigned int lmb_size; 143 int ret = -EINVAL; 144 145 /* 146 * Check to see if we are actually adding memory 147 */ 148 type = of_get_property(np, "device_type", NULL); 149 if (type == NULL || strcmp(type, "memory") != 0) 150 return 0; 151 152 /* 153 * Find the base and size of the memblock 154 */ 155 regs = of_get_property(np, "reg", NULL); 156 if (!regs) 157 return ret; 158 159 base = be64_to_cpu(*(unsigned long *)regs); 160 lmb_size = be32_to_cpu(regs[3]); 161 162 /* 163 * Update memory region to represent the memory add 164 */ 165 ret = memblock_add(base, lmb_size); 166 return (ret < 0) ? -EINVAL : 0; 167 } 168 169 static int pseries_update_drconf_memory(struct of_reconfig_data *pr) 170 { 171 struct of_drconf_cell *new_drmem, *old_drmem; 172 unsigned long memblock_size; 173 u32 entries; 174 __be32 *p; 175 int i, rc = -EINVAL; 176 177 memblock_size = pseries_memory_block_size(); 178 if (!memblock_size) 179 return -EINVAL; 180 181 p = (__be32 *) pr->old_prop->value; 182 if (!p) 183 return -EINVAL; 184 185 /* The first int of the property is the number of lmb's described 186 * by the property. This is followed by an array of of_drconf_cell 187 * entries. Get the number of entries and skip to the array of 188 * of_drconf_cell's. 189 */ 190 entries = be32_to_cpu(*p++); 191 old_drmem = (struct of_drconf_cell *)p; 192 193 p = (__be32 *)pr->prop->value; 194 p++; 195 new_drmem = (struct of_drconf_cell *)p; 196 197 for (i = 0; i < entries; i++) { 198 if ((be32_to_cpu(old_drmem[i].flags) & DRCONF_MEM_ASSIGNED) && 199 (!(be32_to_cpu(new_drmem[i].flags) & DRCONF_MEM_ASSIGNED))) { 200 rc = pseries_remove_memblock( 201 be64_to_cpu(old_drmem[i].base_addr), 202 memblock_size); 203 break; 204 } else if ((!(be32_to_cpu(old_drmem[i].flags) & 205 DRCONF_MEM_ASSIGNED)) && 206 (be32_to_cpu(new_drmem[i].flags) & 207 DRCONF_MEM_ASSIGNED)) { 208 rc = memblock_add(be64_to_cpu(old_drmem[i].base_addr), 209 memblock_size); 210 rc = (rc < 0) ? -EINVAL : 0; 211 break; 212 } 213 } 214 return rc; 215 } 216 217 static int pseries_memory_notifier(struct notifier_block *nb, 218 unsigned long action, void *data) 219 { 220 struct of_reconfig_data *rd = data; 221 int err = 0; 222 223 switch (action) { 224 case OF_RECONFIG_ATTACH_NODE: 225 err = pseries_add_mem_node(rd->dn); 226 break; 227 case OF_RECONFIG_DETACH_NODE: 228 err = pseries_remove_mem_node(rd->dn); 229 break; 230 case OF_RECONFIG_UPDATE_PROPERTY: 231 if (!strcmp(rd->prop->name, "ibm,dynamic-memory")) 232 err = pseries_update_drconf_memory(rd); 233 break; 234 } 235 return notifier_from_errno(err); 236 } 237 238 static struct notifier_block pseries_mem_nb = { 239 .notifier_call = pseries_memory_notifier, 240 }; 241 242 static int __init pseries_memory_hotplug_init(void) 243 { 244 if (firmware_has_feature(FW_FEATURE_LPAR)) 245 of_reconfig_notifier_register(&pseries_mem_nb); 246 247 return 0; 248 } 249 machine_device_initcall(pseries, pseries_memory_hotplug_init); 250