arch/powerpc/platforms/pseries/hotplug-memory.c

   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 #define pr_fmt(fmt)     "pseries-hotplug-mem: " fmt
  13
  14 #include <linux/of.h>
  15 #include <linux/of_address.h>
  16 #include <linux/memblock.h>
  17 #include <linux/memory.h>
  18 #include <linux/memory_hotplug.h>
  19
  20 #include <asm/firmware.h>
  21 #include <asm/machdep.h>
  22 #include <asm/prom.h>
  23 #include <asm/sparsemem.h>
  24 #include "pseries.h"
  25
  26 unsigned long pseries_memory_block_size(void)
  27 {
  28         struct device_node *np;
  29         unsigned int memblock_size = MIN_MEMORY_BLOCK_SIZE;
  30         struct resource r;
  31
  32         np = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
  33         if (np) {
  34                 const __be64 *size;
  35
  36                 size = of_get_property(np, "ibm,lmb-size", NULL);
  37                 if (size)
  38                         memblock_size = be64_to_cpup(size);
  39                 of_node_put(np);
  40         } else  if (machine_is(pseries)) {
  41                 /* This fallback really only applies to pseries */
  42                 unsigned int memzero_size = 0;
  43
  44                 np = of_find_node_by_path("/memory@0");
  45                 if (np) {
  46                         if (!of_address_to_resource(np, 0, &r))
  47                                 memzero_size = resource_size(&r);
  48                         of_node_put(np);
  49                 }
  50
  51                 if (memzero_size) {
  52                         /* We now know the size of memory@0, use this to find
  53                          * the first memoryblock and get its size.
  54                          */
  55                         char buf[64];
  56
  57                         sprintf(buf, "/memory@%x", memzero_size);
  58                         np = of_find_node_by_path(buf);
  59                         if (np) {
  60                                 if (!of_address_to_resource(np, 0, &r))
  61                                         memblock_size = resource_size(&r);
  62                                 of_node_put(np);
  63                         }
  64                 }
  65         }
  66         return memblock_size;
  67 }
  68
  69 #ifdef CONFIG_MEMORY_HOTREMOVE
  70 static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size)
  71 {
  72         unsigned long block_sz, start_pfn;
  73         int sections_per_block;
  74         int i, nid;
  75
  76         start_pfn = base >> PAGE_SHIFT;
  77
  78         lock_device_hotplug();
  79
  80         if (!pfn_valid(start_pfn))
  81                 goto out;
  82
  83         block_sz = pseries_memory_block_size();
  84         sections_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE;
  85         nid = memory_add_physaddr_to_nid(base);
  86
  87         for (i = 0; i < sections_per_block; i++) {
  88                 remove_memory(nid, base, MIN_MEMORY_BLOCK_SIZE);
  89                 base += MIN_MEMORY_BLOCK_SIZE;
  90         }
  91
  92 out:
  93         /* Update memory regions for memory remove */
  94         memblock_remove(base, memblock_size);
  95         unlock_device_hotplug();
  96         return 0;
  97 }
  98
  99 static int pseries_remove_mem_node(struct device_node *np)
 100 {
 101         const char *type;
 102         const __be32 *regs;
 103         unsigned long base;
 104         unsigned int lmb_size;
 105         int ret = -EINVAL;
 106
 107         /*
 108          * Check to see if we are actually removing memory
 109          */
 110         type = of_get_property(np, "device_type", NULL);
 111         if (type == NULL || strcmp(type, "memory") != 0)
 112                 return 0;
 113
 114         /*
 115          * Find the base address and size of the memblock
 116          */
 117         regs = of_get_property(np, "reg", NULL);
 118         if (!regs)
 119                 return ret;
 120
 121         base = be64_to_cpu(*(unsigned long *)regs);
 122         lmb_size = be32_to_cpu(regs[3]);
 123
 124         pseries_remove_memblock(base, lmb_size);
 125         return 0;
 126 }
 127 #else
 128 static inline int pseries_remove_memblock(unsigned long base,
 129                                           unsigned int memblock_size)
 130 {
 131         return -EOPNOTSUPP;
 132 }
 133 static inline int pseries_remove_mem_node(struct device_node *np)
 134 {
 135         return 0;
 136 }
 137 #endif /* CONFIG_MEMORY_HOTREMOVE */
 138
 139 int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
 140 {
 141         int rc = 0;
 142
 143         lock_device_hotplug();
 144
 145         switch (hp_elog->action) {
 146         default:
 147                 pr_err("Invalid action (%d) specified\n", hp_elog->action);
 148                 rc = -EINVAL;
 149                 break;
 150         }
 151
 152         unlock_device_hotplug();
 153         return rc;
 154 }
 155
 156 static int pseries_add_mem_node(struct device_node *np)
 157 {
 158         const char *type;
 159         const __be32 *regs;
 160         unsigned long base;
 161         unsigned int lmb_size;
 162         int ret = -EINVAL;
 163
 164         /*
 165          * Check to see if we are actually adding memory
 166          */
 167         type = of_get_property(np, "device_type", NULL);
 168         if (type == NULL || strcmp(type, "memory") != 0)
 169                 return 0;
 170
 171         /*
 172          * Find the base and size of the memblock
 173          */
 174         regs = of_get_property(np, "reg", NULL);
 175         if (!regs)
 176                 return ret;
 177
 178         base = be64_to_cpu(*(unsigned long *)regs);
 179         lmb_size = be32_to_cpu(regs[3]);
 180
 181         /*
 182          * Update memory region to represent the memory add
 183          */
 184         ret = memblock_add(base, lmb_size);
 185         return (ret < 0) ? -EINVAL : 0;
 186 }
 187
 188 static int pseries_update_drconf_memory(struct of_reconfig_data *pr)
 189 {
 190         struct of_drconf_cell *new_drmem, *old_drmem;
 191         unsigned long memblock_size;
 192         u32 entries;
 193         __be32 *p;
 194         int i, rc = -EINVAL;
 195
 196         memblock_size = pseries_memory_block_size();
 197         if (!memblock_size)
 198                 return -EINVAL;
 199
 200         p = (__be32 *) pr->old_prop->value;
 201         if (!p)
 202                 return -EINVAL;
 203
 204         /* The first int of the property is the number of lmb's described
 205          * by the property. This is followed by an array of of_drconf_cell
 206          * entries. Get the number of entries and skip to the array of
 207          * of_drconf_cell's.
 208          */
 209         entries = be32_to_cpu(*p++);
 210         old_drmem = (struct of_drconf_cell *)p;
 211
 212         p = (__be32 *)pr->prop->value;
 213         p++;
 214         new_drmem = (struct of_drconf_cell *)p;
 215
 216         for (i = 0; i < entries; i++) {
 217                 if ((be32_to_cpu(old_drmem[i].flags) & DRCONF_MEM_ASSIGNED) &&
 218                     (!(be32_to_cpu(new_drmem[i].flags) & DRCONF_MEM_ASSIGNED))) {
 219                         rc = pseries_remove_memblock(
 220                                 be64_to_cpu(old_drmem[i].base_addr),
 221                                                      memblock_size);
 222                         break;
 223                 } else if ((!(be32_to_cpu(old_drmem[i].flags) &
 224                             DRCONF_MEM_ASSIGNED)) &&
 225                             (be32_to_cpu(new_drmem[i].flags) &
 226                             DRCONF_MEM_ASSIGNED)) {
 227                         rc = memblock_add(be64_to_cpu(old_drmem[i].base_addr),
 228                                           memblock_size);
 229                         rc = (rc < 0) ? -EINVAL : 0;
 230                         break;
 231                 }
 232         }
 233         return rc;
 234 }
 235
 236 static int pseries_memory_notifier(struct notifier_block *nb,
 237                                    unsigned long action, void *data)
 238 {
 239         struct of_reconfig_data *rd = data;
 240         int err = 0;
 241
 242         switch (action) {
 243         case OF_RECONFIG_ATTACH_NODE:
 244                 err = pseries_add_mem_node(rd->dn);
 245                 break;
 246         case OF_RECONFIG_DETACH_NODE:
 247                 err = pseries_remove_mem_node(rd->dn);
 248                 break;
 249         case OF_RECONFIG_UPDATE_PROPERTY:
 250                 if (!strcmp(rd->prop->name, "ibm,dynamic-memory"))
 251                         err = pseries_update_drconf_memory(rd);
 252                 break;
 253         }
 254         return notifier_from_errno(err);
 255 }
 256
 257 static struct notifier_block pseries_mem_nb = {
 258         .notifier_call = pseries_memory_notifier,
 259 };
 260
 261 static int __init pseries_memory_hotplug_init(void)
 262 {
 263         if (firmware_has_feature(FW_FEATURE_LPAR))
 264                 of_reconfig_notifier_register(&pseries_mem_nb);
 265
 266         return 0;
 267 }
 268 machine_device_initcall(pseries, pseries_memory_hotplug_init);