arch/powerpc/platforms/iseries/dt.c

   1 /*
   2  *    Copyright (C) 2005-2006 Michael Ellerman, IBM Corporation
   3  *    Copyright (C) 2000-2004, IBM Corporation
   4  *
   5  *    Description:
   6  *      This file contains all the routines to build a flattened device
   7  *      tree for a legacy iSeries machine.
   8  *
   9  *      This program is free software; you can redistribute it and/or
  10  *      modify it under the terms of the GNU General Public License
  11  *      as published by the Free Software Foundation; either version
  12  *      2 of the License, or (at your option) any later version.
  13  */
  14
  15 #undef DEBUG
  16
  17 #include <linux/types.h>
  18 #include <linux/init.h>
  19 #include <linux/pci.h>
  20 #include <linux/pci_regs.h>
  21 #include <linux/pci_ids.h>
  22 #include <linux/threads.h>
  23 #include <linux/bitops.h>
  24 #include <linux/string.h>
  25 #include <linux/kernel.h>
  26 #include <linux/if_ether.h>     /* ETH_ALEN */
  27
  28 #include <asm/machdep.h>
  29 #include <asm/prom.h>
  30 #include <asm/lppaca.h>
  31 #include <asm/cputable.h>
  32 #include <asm/abs_addr.h>
  33 #include <asm/system.h>
  34 #include <asm/iseries/hv_types.h>
  35 #include <asm/iseries/hv_lp_config.h>
  36 #include <asm/iseries/hv_call_xm.h>
  37 #include <asm/udbg.h>
  38
  39 #include "processor_vpd.h"
  40 #include "call_hpt.h"
  41 #include "call_pci.h"
  42 #include "pci.h"
  43 #include "it_exp_vpd_panel.h"
  44 #include "naca.h"
  45
  46 #ifdef DEBUG
  47 #define DBG(fmt...) udbg_printf(fmt)
  48 #else
  49 #define DBG(fmt...)
  50 #endif
  51
  52 /*
  53  * These are created by the linker script at the start and end
  54  * of the section containing all the strings from this file.
  55  */
  56 extern char __dt_strings_start[];
  57 extern char __dt_strings_end[];
  58
  59 struct iseries_flat_dt {
  60         struct boot_param_header header;
  61         u64 reserve_map[2];
  62 };
  63
  64 static void * __initdata dt_data;
  65
  66 /*
  67  * Putting these strings here keeps them out of the section
  68  * that we rename to .dt_strings using objcopy and capture
  69  * for the strings blob of the flattened device tree.
  70  */
  71 static char __initdata device_type_cpu[] = "cpu";
  72 static char __initdata device_type_memory[] = "memory";
  73 static char __initdata device_type_serial[] = "serial";
  74 static char __initdata device_type_network[] = "network";
  75 static char __initdata device_type_block[] = "block";
  76 static char __initdata device_type_byte[] = "byte";
  77 static char __initdata device_type_pci[] = "pci";
  78 static char __initdata device_type_vdevice[] = "vdevice";
  79 static char __initdata device_type_vscsi[] = "vscsi";
  80
  81
  82 /* EBCDIC to ASCII conversion routines */
  83
  84 static unsigned char __init e2a(unsigned char x)
  85 {
  86         switch (x) {
  87         case 0x81 ... 0x89:
  88                 return x - 0x81 + 'a';
  89         case 0x91 ... 0x99:
  90                 return x - 0x91 + 'j';
  91         case 0xA2 ... 0xA9:
  92                 return x - 0xA2 + 's';
  93         case 0xC1 ... 0xC9:
  94                 return x - 0xC1 + 'A';
  95         case 0xD1 ... 0xD9:
  96                 return x - 0xD1 + 'J';
  97         case 0xE2 ... 0xE9:
  98                 return x - 0xE2 + 'S';
  99         case 0xF0 ... 0xF9:
 100                 return x - 0xF0 + '0';
 101         }
 102         return ' ';
 103 }
 104
 105 static unsigned char * __init strne2a(unsigned char *dest,
 106                 const unsigned char *src, size_t n)
 107 {
 108         int i;
 109
 110         n = strnlen(src, n);
 111
 112         for (i = 0; i < n; i++)
 113                 dest[i] = e2a(src[i]);
 114
 115         return dest;
 116 }
 117
 118 static struct iseries_flat_dt * __init dt_init(void)
 119 {
 120         struct iseries_flat_dt *dt;
 121         unsigned long str_len;
 122
 123         str_len = __dt_strings_end - __dt_strings_start;
 124         dt = (struct iseries_flat_dt *)ALIGN(klimit, 8);
 125         dt->header.off_mem_rsvmap =
 126                 offsetof(struct iseries_flat_dt, reserve_map);
 127         dt->header.off_dt_strings = ALIGN(sizeof(*dt), 8);
 128         dt->header.off_dt_struct = dt->header.off_dt_strings
 129                 + ALIGN(str_len, 8);
 130         dt_data = (void *)((unsigned long)dt + dt->header.off_dt_struct);
 131         dt->header.dt_strings_size = str_len;
 132
 133         /* There is no notion of hardware cpu id on iSeries */
 134         dt->header.boot_cpuid_phys = smp_processor_id();
 135
 136         memcpy((char *)dt + dt->header.off_dt_strings, __dt_strings_start,
 137                         str_len);
 138
 139         dt->header.magic = OF_DT_HEADER;
 140         dt->header.version = 0x10;
 141         dt->header.last_comp_version = 0x10;
 142
 143         dt->reserve_map[0] = 0;
 144         dt->reserve_map[1] = 0;
 145
 146         return dt;
 147 }
 148
 149 static void __init dt_push_u32(struct iseries_flat_dt *dt, u32 value)
 150 {
 151         *((u32 *)dt_data) = value;
 152         dt_data += sizeof(u32);
 153 }
 154
 155 #ifdef notyet
 156 static void __init dt_push_u64(struct iseries_flat_dt *dt, u64 value)
 157 {
 158         *((u64 *)dt_data) = value;
 159         dt_data += sizeof(u64);
 160 }
 161 #endif
 162
 163 static void __init dt_push_bytes(struct iseries_flat_dt *dt, const char *data,
 164                 int len)
 165 {
 166         memcpy(dt_data, data, len);
 167         dt_data += ALIGN(len, 4);
 168 }
 169
 170 static void __init dt_start_node(struct iseries_flat_dt *dt, const char *name)
 171 {
 172         dt_push_u32(dt, OF_DT_BEGIN_NODE);
 173         dt_push_bytes(dt, name, strlen(name) + 1);
 174 }
 175
 176 #define dt_end_node(dt) dt_push_u32(dt, OF_DT_END_NODE)
 177
 178 static void __init dt_prop(struct iseries_flat_dt *dt, const char *name,
 179                 const void *data, int len)
 180 {
 181         unsigned long offset;
 182
 183         dt_push_u32(dt, OF_DT_PROP);
 184
 185         /* Length of the data */
 186         dt_push_u32(dt, len);
 187
 188         offset = name - __dt_strings_start;
 189
 190         /* The offset of the properties name in the string blob. */
 191         dt_push_u32(dt, (u32)offset);
 192
 193         /* The actual data. */
 194         dt_push_bytes(dt, data, len);
 195 }
 196
 197 static void __init dt_prop_str(struct iseries_flat_dt *dt, const char *name,
 198                 const char *data)
 199 {
 200         dt_prop(dt, name, data, strlen(data) + 1); /* + 1 for NULL */
 201 }
 202
 203 static void __init dt_prop_u32(struct iseries_flat_dt *dt, const char *name,
 204                 u32 data)
 205 {
 206         dt_prop(dt, name, &data, sizeof(u32));
 207 }
 208
 209 static void __init dt_prop_u64(struct iseries_flat_dt *dt, const char *name,
 210                 u64 data)
 211 {
 212         dt_prop(dt, name, &data, sizeof(u64));
 213 }
 214
 215 static void __init dt_prop_u64_list(struct iseries_flat_dt *dt,
 216                 const char *name, u64 *data, int n)
 217 {
 218         dt_prop(dt, name, data, sizeof(u64) * n);
 219 }
 220
 221 static void __init dt_prop_u32_list(struct iseries_flat_dt *dt,
 222                 const char *name, u32 *data, int n)
 223 {
 224         dt_prop(dt, name, data, sizeof(u32) * n);
 225 }
 226
 227 #ifdef notyet
 228 static void __init dt_prop_empty(struct iseries_flat_dt *dt, const char *name)
 229 {
 230         dt_prop(dt, name, NULL, 0);
 231 }
 232 #endif
 233
 234 static void __init dt_cpus(struct iseries_flat_dt *dt)
 235 {
 236         unsigned char buf[32];
 237         unsigned char *p;
 238         unsigned int i, index;
 239         struct IoHriProcessorVpd *d;
 240         u32 pft_size[2];
 241
 242         /* yuck */
 243         snprintf(buf, 32, "PowerPC,%s", cur_cpu_spec->cpu_name);
 244         p = strchr(buf, ' ');
 245         if (!p) p = buf + strlen(buf);
 246
 247         dt_start_node(dt, "cpus");
 248         dt_prop_u32(dt, "#address-cells", 1);
 249         dt_prop_u32(dt, "#size-cells", 0);
 250
 251         pft_size[0] = 0; /* NUMA CEC cookie, 0 for non NUMA  */
 252         pft_size[1] = __ilog2(HvCallHpt_getHptPages() * HW_PAGE_SIZE);
 253
 254         for (i = 0; i < NR_CPUS; i++) {
 255                 if (lppaca[i].dyn_proc_status >= 2)
 256                         continue;
 257
 258                 snprintf(p, 32 - (p - buf), "@%d", i);
 259                 dt_start_node(dt, buf);
 260
 261                 dt_prop_str(dt, "device_type", device_type_cpu);
 262
 263                 index = lppaca[i].dyn_hv_phys_proc_index;
 264                 d = &xIoHriProcessorVpd[index];
 265
 266                 dt_prop_u32(dt, "i-cache-size", d->xInstCacheSize * 1024);
 267                 dt_prop_u32(dt, "i-cache-line-size", d->xInstCacheOperandSize);
 268
 269                 dt_prop_u32(dt, "d-cache-size", d->xDataL1CacheSizeKB * 1024);
 270                 dt_prop_u32(dt, "d-cache-line-size", d->xDataCacheOperandSize);
 271
 272                 /* magic conversions to Hz copied from old code */
 273                 dt_prop_u32(dt, "clock-frequency",
 274                         ((1UL << 34) * 1000000) / d->xProcFreq);
 275                 dt_prop_u32(dt, "timebase-frequency",
 276                         ((1UL << 32) * 1000000) / d->xTimeBaseFreq);
 277
 278                 dt_prop_u32(dt, "reg", i);
 279
 280                 dt_prop_u32_list(dt, "ibm,pft-size", pft_size, 2);
 281
 282                 dt_end_node(dt);
 283         }
 284
 285         dt_end_node(dt);
 286 }
 287
 288 static void __init dt_model(struct iseries_flat_dt *dt)
 289 {
 290         char buf[16] = "IBM,";
 291
 292         /* N.B. lparcfg.c knows about the "IBM," prefixes ... */
 293         /* "IBM," + mfgId[2:3] + systemSerial[1:5] */
 294         strne2a(buf + 4, xItExtVpdPanel.mfgID + 2, 2);
 295         strne2a(buf + 6, xItExtVpdPanel.systemSerial + 1, 5);
 296         buf[11] = '\0';
 297         dt_prop_str(dt, "system-id", buf);
 298
 299         /* "IBM," + machineType[0:4] */
 300         strne2a(buf + 4, xItExtVpdPanel.machineType, 4);
 301         buf[8] = '\0';
 302         dt_prop_str(dt, "model", buf);
 303
 304         dt_prop_str(dt, "compatible", "IBM,iSeries");
 305         dt_prop_u32(dt, "ibm,partition-no", HvLpConfig_getLpIndex());
 306 }
 307
 308 static void __init dt_initrd(struct iseries_flat_dt *dt)
 309 {
 310 #ifdef CONFIG_BLK_DEV_INITRD
 311         if (naca.xRamDisk) {
 312                 dt_prop_u64(dt, "linux,initrd-start", (u64)naca.xRamDisk);
 313                 dt_prop_u64(dt, "linux,initrd-end",
 314                         (u64)naca.xRamDisk + naca.xRamDiskSize * HW_PAGE_SIZE);
 315         }
 316 #endif
 317 }
 318
 319 static void __init dt_do_vdevice(struct iseries_flat_dt *dt,
 320                 const char *name, u32 reg, int unit,
 321                 const char *type, const char *compat, int end)
 322 {
 323         char buf[32];
 324
 325         snprintf(buf, 32, "%s@%08x", name, reg + ((unit >= 0) ? unit : 0));
 326         dt_start_node(dt, buf);
 327         dt_prop_str(dt, "device_type", type);
 328         if (compat)
 329                 dt_prop_str(dt, "compatible", compat);
 330         dt_prop_u32(dt, "reg", reg + ((unit >= 0) ? unit : 0));
 331         if (unit >= 0)
 332                 dt_prop_u32(dt, "linux,unit_address", unit);
 333         if (end)
 334                 dt_end_node(dt);
 335 }
 336
 337 static void __init dt_vdevices(struct iseries_flat_dt *dt)
 338 {
 339         u32 reg = 0;
 340         HvLpIndexMap vlan_map;
 341         int i;
 342
 343         dt_start_node(dt, "vdevice");
 344         dt_prop_str(dt, "device_type", device_type_vdevice);
 345         dt_prop_str(dt, "compatible", "IBM,iSeries-vdevice");
 346         dt_prop_u32(dt, "#address-cells", 1);
 347         dt_prop_u32(dt, "#size-cells", 0);
 348
 349         dt_do_vdevice(dt, "vty", reg, -1, device_type_serial,
 350                         "IBM,iSeries-vty", 1);
 351         reg++;
 352
 353         dt_do_vdevice(dt, "v-scsi", reg, -1, device_type_vscsi,
 354                         "IBM,v-scsi", 1);
 355         reg++;
 356
 357         vlan_map = HvLpConfig_getVirtualLanIndexMap();
 358         for (i = 0; i < HVMAXARCHITECTEDVIRTUALLANS; i++) {
 359                 unsigned char mac_addr[ETH_ALEN];
 360
 361                 if ((vlan_map & (0x8000 >> i)) == 0)
 362                         continue;
 363                 dt_do_vdevice(dt, "l-lan", reg, i, device_type_network,
 364                                 "IBM,iSeries-l-lan", 0);
 365                 mac_addr[0] = 0x02;
 366                 mac_addr[1] = 0x01;
 367                 mac_addr[2] = 0xff;
 368                 mac_addr[3] = i;
 369                 mac_addr[4] = 0xff;
 370                 mac_addr[5] = HvLpConfig_getLpIndex_outline();
 371                 dt_prop(dt, "local-mac-address", (char *)mac_addr, ETH_ALEN);
 372                 dt_prop(dt, "mac-address", (char *)mac_addr, ETH_ALEN);
 373                 dt_prop_u32(dt, "max-frame-size", 9000);
 374                 dt_prop_u32(dt, "address-bits", 48);
 375
 376                 dt_end_node(dt);
 377         }
 378         reg += HVMAXARCHITECTEDVIRTUALLANS;
 379
 380         for (i = 0; i < HVMAXARCHITECTEDVIRTUALDISKS; i++)
 381                 dt_do_vdevice(dt, "viodasd", reg, i, device_type_block,
 382                                 "IBM,iSeries-viodasd", 1);
 383         reg += HVMAXARCHITECTEDVIRTUALDISKS;
 384
 385         for (i = 0; i < HVMAXARCHITECTEDVIRTUALCDROMS; i++)
 386                 dt_do_vdevice(dt, "viocd", reg, i, device_type_block,
 387                                 "IBM,iSeries-viocd", 1);
 388         reg += HVMAXARCHITECTEDVIRTUALCDROMS;
 389
 390         for (i = 0; i < HVMAXARCHITECTEDVIRTUALTAPES; i++)
 391                 dt_do_vdevice(dt, "viotape", reg, i, device_type_byte,
 392                                 "IBM,iSeries-viotape", 1);
 393
 394         dt_end_node(dt);
 395 }
 396
 397 struct pci_class_name {
 398         u16 code;
 399         const char *name;
 400         const char *type;
 401 };
 402
 403 static struct pci_class_name __initdata pci_class_name[] = {
 404         { PCI_CLASS_NETWORK_ETHERNET, "ethernet", device_type_network },
 405 };
 406
 407 static struct pci_class_name * __init dt_find_pci_class_name(u16 class_code)
 408 {
 409         struct pci_class_name *cp;
 410
 411         for (cp = pci_class_name;
 412                         cp < &pci_class_name[ARRAY_SIZE(pci_class_name)]; cp++)
 413                 if (cp->code == class_code)
 414                         return cp;
 415         return NULL;
 416 }
 417
 418 /*
 419  * This assumes that the node slot is always on the primary bus!
 420  */
 421 static void __init scan_bridge_slot(struct iseries_flat_dt *dt,
 422                 HvBusNumber bus, struct HvCallPci_BridgeInfo *bridge_info)
 423 {
 424         HvSubBusNumber sub_bus = bridge_info->subBusNumber;
 425         u16 vendor_id;
 426         u16 device_id;
 427         u32 class_id;
 428         int err;
 429         char buf[32];
 430         u32 reg[5];
 431         int id_sel = ISERIES_GET_DEVICE_FROM_SUBBUS(sub_bus);
 432         int function = ISERIES_GET_FUNCTION_FROM_SUBBUS(sub_bus);
 433         HvAgentId eads_id_sel = ISERIES_PCI_AGENTID(id_sel, function);
 434         u8 devfn;
 435         struct pci_class_name *cp;
 436
 437         /*
 438          * Connect all functions of any device found.
 439          */
 440         for (id_sel = 1; id_sel <= bridge_info->maxAgents; id_sel++) {
 441                 for (function = 0; function < 8; function++) {
 442                         HvAgentId agent_id = ISERIES_PCI_AGENTID(id_sel,
 443                                         function);
 444                         err = HvCallXm_connectBusUnit(bus, sub_bus,
 445                                         agent_id, 0);
 446                         if (err) {
 447                                 if (err != 0x302)
 448                                         DBG("connectBusUnit(%x, %x, %x) %x\n",
 449                                                 bus, sub_bus, agent_id, err);
 450                                 continue;
 451                         }
 452
 453                         err = HvCallPci_configLoad16(bus, sub_bus, agent_id,
 454                                         PCI_VENDOR_ID, &vendor_id);
 455                         if (err) {
 456                                 DBG("ReadVendor(%x, %x, %x) %x\n",
 457                                         bus, sub_bus, agent_id, err);
 458                                 continue;
 459                         }
 460                         err = HvCallPci_configLoad16(bus, sub_bus, agent_id,
 461                                         PCI_DEVICE_ID, &device_id);
 462                         if (err) {
 463                                 DBG("ReadDevice(%x, %x, %x) %x\n",
 464                                         bus, sub_bus, agent_id, err);
 465                                 continue;
 466                         }
 467                         err = HvCallPci_configLoad32(bus, sub_bus, agent_id,
 468                                         PCI_CLASS_REVISION , &class_id);
 469                         if (err) {
 470                                 DBG("ReadClass(%x, %x, %x) %x\n",
 471                                         bus, sub_bus, agent_id, err);
 472                                 continue;
 473                         }
 474
 475                         devfn = PCI_DEVFN(ISERIES_ENCODE_DEVICE(eads_id_sel),
 476                                         function);
 477                         cp = dt_find_pci_class_name(class_id >> 16);
 478                         if (cp && cp->name)
 479                                 strncpy(buf, cp->name, sizeof(buf) - 1);
 480                         else
 481                                 snprintf(buf, sizeof(buf), "pci%x,%x",
 482                                                 vendor_id, device_id);
 483                         buf[sizeof(buf) - 1] = '\0';
 484                         snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf),
 485                                         "@%x", PCI_SLOT(devfn));
 486                         buf[sizeof(buf) - 1] = '\0';
 487                         if (function != 0)
 488                                 snprintf(buf + strlen(buf),
 489                                         sizeof(buf) - strlen(buf),
 490                                         ",%x", function);
 491                         dt_start_node(dt, buf);
 492                         reg[0] = (bus << 16) | (devfn << 8);
 493                         reg[1] = 0;
 494                         reg[2] = 0;
 495                         reg[3] = 0;
 496                         reg[4] = 0;
 497                         dt_prop_u32_list(dt, "reg", reg, 5);
 498                         if (cp && (cp->type || cp->name))
 499                                 dt_prop_str(dt, "device_type",
 500                                         cp->type ? cp->type : cp->name);
 501                         dt_prop_u32(dt, "vendor-id", vendor_id);
 502                         dt_prop_u32(dt, "device-id", device_id);
 503                         dt_prop_u32(dt, "class-code", class_id >> 8);
 504                         dt_prop_u32(dt, "revision-id", class_id & 0xff);
 505                         dt_prop_u32(dt, "linux,subbus", sub_bus);
 506                         dt_prop_u32(dt, "linux,agent-id", agent_id);
 507                         dt_prop_u32(dt, "linux,logical-slot-number",
 508                                         bridge_info->logicalSlotNumber);
 509                         dt_end_node(dt);
 510
 511                 }
 512         }
 513 }
 514
 515 static void __init scan_bridge(struct iseries_flat_dt *dt, HvBusNumber bus,
 516                 HvSubBusNumber sub_bus, int id_sel)
 517 {
 518         struct HvCallPci_BridgeInfo bridge_info;
 519         HvAgentId agent_id;
 520         int function;
 521         int ret;
 522
 523         /* Note: hvSubBus and irq is always be 0 at this level! */
 524         for (function = 0; function < 8; ++function) {
 525                 agent_id = ISERIES_PCI_AGENTID(id_sel, function);
 526                 ret = HvCallXm_connectBusUnit(bus, sub_bus, agent_id, 0);
 527                 if (ret != 0) {
 528                         if (ret != 0xb)
 529                                 DBG("connectBusUnit(%x, %x, %x) %x\n",
 530                                                 bus, sub_bus, agent_id, ret);
 531                         continue;
 532                 }
 533                 DBG("found device at bus %d idsel %d func %d (AgentId %x)\n",
 534                                 bus, id_sel, function, agent_id);
 535                 ret = HvCallPci_getBusUnitInfo(bus, sub_bus, agent_id,
 536                                 iseries_hv_addr(&bridge_info),
 537                                 sizeof(struct HvCallPci_BridgeInfo));
 538                 if (ret != 0)
 539                         continue;
 540                 DBG("bridge info: type %x subbus %x "
 541                         "maxAgents %x maxsubbus %x logslot %x\n",
 542                         bridge_info.busUnitInfo.deviceType,
 543                         bridge_info.subBusNumber,
 544                         bridge_info.maxAgents,
 545                         bridge_info.maxSubBusNumber,
 546                         bridge_info.logicalSlotNumber);
 547                 if (bridge_info.busUnitInfo.deviceType ==
 548                                 HvCallPci_BridgeDevice)
 549                         scan_bridge_slot(dt, bus, &bridge_info);
 550                 else
 551                         DBG("PCI: Invalid Bridge Configuration(0x%02X)",
 552                                 bridge_info.busUnitInfo.deviceType);
 553         }
 554 }
 555
 556 static void __init scan_phb(struct iseries_flat_dt *dt, HvBusNumber bus)
 557 {
 558         struct HvCallPci_DeviceInfo dev_info;
 559         const HvSubBusNumber sub_bus = 0;       /* EADs is always 0. */
 560         int err;
 561         int id_sel;
 562         const int max_agents = 8;
 563
 564         /*
 565          * Probe for EADs Bridges
 566          */
 567         for (id_sel = 1; id_sel < max_agents; ++id_sel) {
 568                 err = HvCallPci_getDeviceInfo(bus, sub_bus, id_sel,
 569                                 iseries_hv_addr(&dev_info),
 570                                 sizeof(struct HvCallPci_DeviceInfo));
 571                 if (err) {
 572                         if (err != 0x302)
 573                                 DBG("getDeviceInfo(%x, %x, %x) %x\n",
 574                                                 bus, sub_bus, id_sel, err);
 575                         continue;
 576                 }
 577                 if (dev_info.deviceType != HvCallPci_NodeDevice) {
 578                         DBG("PCI: Invalid System Configuration"
 579                                         "(0x%02X) for bus 0x%02x id 0x%02x.\n",
 580                                         dev_info.deviceType, bus, id_sel);
 581                         continue;
 582                 }
 583                 scan_bridge(dt, bus, sub_bus, id_sel);
 584         }
 585 }
 586
 587 static void __init dt_pci_devices(struct iseries_flat_dt *dt)
 588 {
 589         HvBusNumber bus;
 590         char buf[32];
 591         u32 buses[2];
 592         int phb_num = 0;
 593
 594         /* Check all possible buses. */
 595         for (bus = 0; bus < 256; bus++) {
 596                 int err = HvCallXm_testBus(bus);
 597
 598                 if (err) {
 599                         /*
 600                          * Check for Unexpected Return code, a clue that
 601                          * something has gone wrong.
 602                          */
 603                         if (err != 0x0301)
 604                                 DBG("Unexpected Return on Probe(0x%02X) "
 605                                                 "0x%04X\n", bus, err);
 606                         continue;
 607                 }
 608                 DBG("bus %d appears to exist\n", bus);
 609                 snprintf(buf, 32, "pci@%d", phb_num);
 610                 dt_start_node(dt, buf);
 611                 dt_prop_str(dt, "device_type", device_type_pci);
 612                 dt_prop_str(dt, "compatible", "IBM,iSeries-Logical-PHB");
 613                 dt_prop_u32(dt, "#address-cells", 3);
 614                 dt_prop_u32(dt, "#size-cells", 2);
 615                 buses[0] = buses[1] = bus;
 616                 dt_prop_u32_list(dt, "bus-range", buses, 2);
 617                 scan_phb(dt, bus);
 618                 dt_end_node(dt);
 619                 phb_num++;
 620         }
 621 }
 622
 623 static void dt_finish(struct iseries_flat_dt *dt)
 624 {
 625         dt_push_u32(dt, OF_DT_END);
 626         dt->header.totalsize = (unsigned long)dt_data - (unsigned long)dt;
 627         klimit = ALIGN((unsigned long)dt_data, 8);
 628 }
 629
 630 void * __init build_flat_dt(unsigned long phys_mem_size)
 631 {
 632         struct iseries_flat_dt *iseries_dt;
 633         u64 tmp[2];
 634
 635         iseries_dt = dt_init();
 636
 637         dt_start_node(iseries_dt, "");
 638
 639         dt_prop_u32(iseries_dt, "#address-cells", 2);
 640         dt_prop_u32(iseries_dt, "#size-cells", 2);
 641         dt_model(iseries_dt);
 642
 643         /* /memory */
 644         dt_start_node(iseries_dt, "memory@0");
 645         dt_prop_str(iseries_dt, "device_type", device_type_memory);
 646         tmp[0] = 0;
 647         tmp[1] = phys_mem_size;
 648         dt_prop_u64_list(iseries_dt, "reg", tmp, 2);
 649         dt_end_node(iseries_dt);
 650
 651         /* /chosen */
 652         dt_start_node(iseries_dt, "chosen");
 653         dt_prop_str(iseries_dt, "bootargs", cmd_line);
 654         dt_initrd(iseries_dt);
 655         dt_end_node(iseries_dt);
 656
 657         dt_cpus(iseries_dt);
 658
 659         dt_vdevices(iseries_dt);
 660         dt_pci_devices(iseries_dt);
 661
 662         dt_end_node(iseries_dt);
 663
 664         dt_finish(iseries_dt);
 665
 666         return iseries_dt;
 667 }