qemu/target-ia64/firmware.c

   1 /*
   2  * firmware.c : Firmware build logic for ia64 platform.
   3  *
   4  * Ported from Xen 3.0 Source.
   5  * Copyright (c) 2007, Intel Corporation.
   6  * Zhang Xiantao <xiantao.zhang@intel.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms and conditions of the GNU General Public License,
  10  * version 2, as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope it will be useful, but WITHOUT
  13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  15  * more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along with
  18  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  19  * Place - Suite 330, Boston, MA 02111-1307 USA.
  20  */
  21
  22 #include <string.h>
  23 #include <stdlib.h>
  24 #include <zlib.h>
  25 #include <sys/types.h>
  26 #include <sys/stat.h>
  27 #include <fcntl.h>
  28
  29 #include "cpu.h"
  30
  31 #include "firmware.h"
  32
  33 typedef struct {
  34     unsigned long signature;
  35     unsigned int  type;
  36     unsigned int  length;
  37 } HOB_GENERIC_HEADER;
  38
  39 /*
  40  * INFO HOB is the first data data in one HOB list
  41  * it contains the control information of the HOB list
  42  */
  43 typedef struct {
  44     HOB_GENERIC_HEADER  header;
  45     unsigned long       length;    // current length of hob
  46     unsigned long       cur_pos;   // current poisiton of hob
  47     unsigned long       buf_size;  // size of hob buffer
  48 } HOB_INFO;
  49
  50 typedef struct{
  51     unsigned long start;
  52     unsigned long size;
  53 } hob_mem_t;
  54
  55 typedef enum {
  56     HOB_TYPE_INFO=0,
  57     HOB_TYPE_TERMINAL,
  58     HOB_TYPE_MEM,
  59     HOB_TYPE_PAL_BUS_GET_FEATURES_DATA,
  60     HOB_TYPE_PAL_CACHE_SUMMARY,
  61     HOB_TYPE_PAL_MEM_ATTRIB,
  62     HOB_TYPE_PAL_CACHE_INFO,
  63     HOB_TYPE_PAL_CACHE_PROT_INFO,
  64     HOB_TYPE_PAL_DEBUG_INFO,
  65     HOB_TYPE_PAL_FIXED_ADDR,
  66     HOB_TYPE_PAL_FREQ_BASE,
  67     HOB_TYPE_PAL_FREQ_RATIOS,
  68     HOB_TYPE_PAL_HALT_INFO,
  69     HOB_TYPE_PAL_PERF_MON_INFO,
  70     HOB_TYPE_PAL_PROC_GET_FEATURES,
  71     HOB_TYPE_PAL_PTCE_INFO,
  72     HOB_TYPE_PAL_REGISTER_INFO,
  73     HOB_TYPE_PAL_RSE_INFO,
  74     HOB_TYPE_PAL_TEST_INFO,
  75     HOB_TYPE_PAL_VM_SUMMARY,
  76     HOB_TYPE_PAL_VM_INFO,
  77     HOB_TYPE_PAL_VM_PAGE_SIZE,
  78     HOB_TYPE_NR_VCPU,
  79     HOB_TYPE_NR_NVRAM,
  80     HOB_TYPE_MAX
  81 } hob_type_t;
  82
  83 static int hob_init(void  *buffer ,unsigned long buf_size);
  84 static int add_pal_hob(void* hob_buf);
  85 static int add_mem_hob(void* hob_buf, unsigned long dom_mem_size);
  86 static int add_vcpus_hob(void* hob_buf, unsigned long nr_vcpu);
  87 static int build_hob(void* hob_buf, unsigned long hob_buf_size,
  88                      unsigned long dom_mem_size, unsigned long vcpus);
  89 static int load_hob(void *hob_buf,
  90                     unsigned long dom_mem_size, void* hob_start);
  91
  92 int
  93 kvm_ia64_build_hob(unsigned long memsize,
  94             unsigned long vcpus, uint8_t* fw_start)
  95 {
  96     char   *hob_buf;
  97
  98     hob_buf = malloc(GFW_HOB_SIZE);
  99     if (hob_buf == NULL) {
 100         Hob_Output("Hob: Could not allocate hob");
 101         return -1;
 102     }
 103
 104     if (build_hob(hob_buf, GFW_HOB_SIZE, memsize, vcpus) < 0) {
 105         free(hob_buf);
 106         Hob_Output("Could not build hob");
 107         return -1;
 108     }
 109     if (load_hob(hob_buf, memsize, fw_start + HOB_OFFSET) < 0) {
 110         free(hob_buf);
 111         Hob_Output("Could not load hob");
 112         return -1;
 113     }
 114     free(hob_buf);
 115     return 0;
 116
 117 }
 118
 119 static int
 120 hob_init(void *buffer, unsigned long buf_size)
 121 {
 122     HOB_INFO *phit;
 123     HOB_GENERIC_HEADER *terminal;
 124
 125     if (sizeof(HOB_INFO) + sizeof(HOB_GENERIC_HEADER) > buf_size) {
 126         // buffer too small
 127         return -1;
 128     }
 129
 130     phit = (HOB_INFO*)buffer;
 131     phit->header.signature = HOB_SIGNATURE;
 132     phit->header.type = HOB_TYPE_INFO;
 133     phit->header.length = sizeof(HOB_INFO);
 134     phit->length = sizeof(HOB_INFO) + sizeof(HOB_GENERIC_HEADER);
 135     phit->cur_pos = 0;
 136     phit->buf_size = buf_size;
 137
 138     terminal = (HOB_GENERIC_HEADER*)(buffer + sizeof(HOB_INFO));
 139     terminal->signature = HOB_SIGNATURE;
 140     terminal->type = HOB_TYPE_TERMINAL;
 141     terminal->length = sizeof(HOB_GENERIC_HEADER);
 142
 143     return 0;
 144 }
 145
 146 /*
 147  *  Add a new HOB to the HOB List.
 148  *
 149  *  hob_start  -  start address of hob buffer
 150  *  type       -  type of the hob to be added
 151  *  data       -  data of the hob to be added
 152  *  data_size  -  size of the data
 153  */
 154 static int
 155 hob_add(void* hob_start, int type, void* data, int data_size)
 156 {
 157     HOB_INFO *phit;
 158     HOB_GENERIC_HEADER *newhob, *tail;
 159
 160     phit = (HOB_INFO*)hob_start;
 161
 162     if (phit->length + data_size > phit->buf_size) {
 163         // no space for new hob
 164         return -1;
 165     }
 166
 167     //append new HOB
 168     newhob = (HOB_GENERIC_HEADER*)(hob_start + phit->length -
 169                                    sizeof(HOB_GENERIC_HEADER));
 170     newhob->signature = HOB_SIGNATURE;
 171     newhob->type = type;
 172     newhob->length = data_size + sizeof(HOB_GENERIC_HEADER);
 173     memcpy((void*)newhob + sizeof(HOB_GENERIC_HEADER), data, data_size);
 174
 175     // append terminal HOB
 176     tail = (HOB_GENERIC_HEADER*)(hob_start + phit->length + data_size);
 177     tail->signature = HOB_SIGNATURE;
 178     tail->type = HOB_TYPE_TERMINAL;
 179     tail->length = sizeof(HOB_GENERIC_HEADER);
 180
 181     // adjust HOB list length
 182     phit->length += sizeof(HOB_GENERIC_HEADER) + data_size;
 183
 184     return 0;
 185 }
 186
 187 static int
 188 get_hob_size(void* hob_buf)
 189 {
 190     HOB_INFO *phit = (HOB_INFO*)hob_buf;
 191
 192     if (phit->header.signature != HOB_SIGNATURE) {
 193         Hob_Output("xc_get_hob_size:Incorrect signature");
 194         return -1;
 195     }
 196     return phit->length;
 197 }
 198
 199 static  int
 200 add_max_hob_entry(void* hob_buf)
 201 {
 202     long max_hob = 0;
 203     return hob_add(hob_buf, HOB_TYPE_MAX, &max_hob, sizeof(long));
 204 }
 205
 206 static int
 207 build_hob(void* hob_buf, unsigned long hob_buf_size,
 208           unsigned long dom_mem_size, unsigned long vcpus)
 209 {
 210     //Init HOB List
 211     if (hob_init(hob_buf, hob_buf_size) < 0) {
 212         Hob_Output("buffer too small");
 213         goto err_out;
 214     }
 215
 216     if (add_mem_hob(hob_buf,dom_mem_size) < 0) {
 217         Hob_Output("Add memory hob failed, buffer too small");
 218         goto err_out;
 219     }
 220
 221     if (add_vcpus_hob(hob_buf, vcpus) < 0) {
 222         Hob_Output("Add NR_VCPU hob failed, buffer too small");
 223         goto err_out;
 224     }
 225
 226     if (add_pal_hob( hob_buf ) < 0) {
 227         Hob_Output("Add PAL hob failed, buffer too small");
 228         goto err_out;
 229     }
 230
 231     if (add_max_hob_entry(hob_buf) < 0) {
 232         Hob_Output("Add max hob entry failed, buffer too small");
 233         goto err_out;
 234     }
 235     return 0;
 236
 237 err_out:
 238     return -1;
 239 }
 240 static int
 241 load_hob(void *hob_buf,
 242          unsigned long dom_mem_size, void* hob_start)
 243 {
 244     int hob_size;
 245
 246     hob_size = get_hob_size(hob_buf);
 247     if (hob_size < 0) {
 248         Hob_Output("Invalid hob data");
 249         return -1;
 250     }
 251
 252     if (hob_size > GFW_HOB_SIZE) {
 253         Hob_Output("No enough memory for hob data");
 254         return -1;
 255     }
 256     memcpy (hob_start, hob_buf, hob_size);
 257     return 0;
 258 }
 259
 260 static int
 261 add_mem_hob(void* hob_buf, unsigned long dom_mem_size)
 262 {
 263     hob_mem_t memhob;
 264
 265     // less than 3G
 266     memhob.start = 0;
 267     memhob.size = MIN(dom_mem_size, 0xC0000000);
 268
 269     if (hob_add(hob_buf, HOB_TYPE_MEM, &memhob, sizeof(memhob)) < 0)
 270         return -1;
 271
 272     if (dom_mem_size > 0xC0000000) {
 273         // 4G ~ 4G+remain
 274         memhob.start = 0x100000000; //4G
 275         memhob.size = dom_mem_size - 0xC0000000;
 276         if (hob_add(hob_buf, HOB_TYPE_MEM, &memhob, sizeof(memhob)) < 0)
 277             return -1;
 278     }
 279     return 0;
 280 }
 281
 282 static int
 283 add_vcpus_hob(void* hob_buf, unsigned long vcpus)
 284 {
 285     return hob_add(hob_buf, HOB_TYPE_NR_VCPU, &vcpus, sizeof(vcpus));
 286 }
 287
 288 static const unsigned char config_pal_bus_get_features_data[24] = {
 289     0, 0, 0, 32, 0, 0, 240, 189, 0, 0, 0, 0, 0, 0,
 290     0, 0, 0, 0, 0, 0, 0, 0, 0, 0
 291 };
 292
 293 static const unsigned char config_pal_cache_summary[16] = {
 294     3, 0, 0, 0, 0, 0, 0, 0, 5, 0, 0, 0, 0, 0, 0, 0
 295 };
 296
 297 static const unsigned char config_pal_mem_attrib[8] = {
 298     241, 0, 0, 0, 0, 0, 0, 0
 299 };
 300
 301 static const unsigned char config_pal_cache_info[152] = {
 302     3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 303     6, 4, 6, 7, 255, 1, 0, 1, 0, 64, 0, 0, 12, 12,
 304     49, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 6, 7, 0, 1,
 305     0, 1, 0, 64, 0, 0, 12, 12, 49, 0, 0, 0, 0, 0, 0,
 306     0, 0, 0, 6, 8, 7, 7, 255, 7, 0, 11, 0, 0, 16, 0,
 307     12, 17, 49, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 8, 7,
 308     7, 7, 5, 9, 11, 0, 0, 4, 0, 12, 15, 49, 0, 254, 255,
 309     255, 255, 255, 255, 255, 255, 2, 8, 7, 7, 7, 5, 9,
 310     11, 0, 0, 4, 0, 12, 15, 49, 0, 0, 0, 0, 0, 0, 0, 0,
 311     0, 3, 12, 7, 7, 7, 14, 1, 3, 0, 0, 192, 0, 12, 20, 49, 0
 312 };
 313
 314 static const unsigned char config_pal_cache_prot_info[200] = {
 315     3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 316     45, 0, 16, 8, 0, 76, 12, 64, 0, 0, 0, 0, 0, 0, 0,
 317     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 318     8, 0, 16, 4, 0, 76, 44, 68, 0, 0, 0, 0, 0, 0, 0, 0,
 319     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 32,
 320     0, 16, 8, 0, 81, 44, 72, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 321     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 32, 0,
 322     112, 12, 0, 79, 124, 76, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 323     0, 0, 0, 0, 0, 0, 254, 255, 255, 255, 255, 255, 255, 255,
 324     32, 0, 112, 12, 0, 79, 124, 76, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 325     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 255, 0, 160,
 326     12, 0, 84, 124, 76, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 327     0, 0, 0
 328 };
 329
 330 static const unsigned char config_pal_debug_info[16] = {
 331     2, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0
 332 };
 333
 334 static const unsigned char config_pal_fixed_addr[8] = {
 335     0, 0, 0, 0, 0, 0, 0, 0
 336 };
 337
 338 static const unsigned char config_pal_freq_base[8] = {
 339     109, 219, 182, 13, 0, 0, 0, 0
 340 };
 341
 342 static const unsigned char config_pal_freq_ratios[24] = {
 343     11, 1, 0, 0, 77, 7, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 4,
 344     0, 0, 0, 7, 0, 0, 0
 345 };
 346
 347 static const unsigned char config_pal_halt_info[64] = {
 348     0, 0, 0, 0, 0, 0, 0, 48, 0, 0, 0, 0, 0, 0, 0, 0,
 349     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 350     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 351     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
 352 };
 353
 354 static const unsigned char config_pal_perf_mon_info[136] = {
 355     12, 47, 18, 8, 0, 0, 0, 0, 241, 255, 0, 0, 255, 7, 0, 0,
 356     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 357     0, 0, 0, 0, 0, 0, 0, 0, 241, 255, 0, 0, 223, 0, 255, 255,
 358     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 359     0, 0, 0, 0, 0, 0, 0, 0, 240, 255, 0, 0, 0, 0, 0, 0,
 360     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 361     0, 0, 0, 0, 0, 0, 0, 0, 240, 255, 0, 0, 0, 0, 0, 0,
 362     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 363     0, 0, 0, 0, 0, 0, 0, 0
 364 };
 365
 366 static const unsigned char config_pal_proc_get_features[104] = {
 367     3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 368     0, 0, 0, 0, 64, 6, 64, 49, 0, 0, 0, 0, 64, 6, 0, 0,
 369     0, 0, 0, 0, 0, 0, 0, 0, 16, 0, 0, 0, 0, 0, 0, 0,
 370     231, 0, 0, 0, 0, 0, 0, 0, 228, 0, 0, 0, 0, 0, 0, 0,
 371     0, 0, 0, 0, 0, 0, 0, 0, 17, 0, 0, 0, 0, 0, 0, 0,
 372     63, 0, 0, 0, 0, 0, 0, 0, 32, 0, 0, 0, 0, 0, 0, 0,
 373     0, 0, 0, 0, 0, 0, 0, 0
 374 };
 375
 376 static const unsigned char config_pal_ptce_info[24] = {
 377     0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0,
 378     0, 0, 0, 0, 0, 0, 0, 0
 379 };
 380
 381 static const unsigned char config_pal_register_info[64] = {
 382     255, 0, 47, 127, 17, 17, 0, 0, 7, 0, 0, 0, 0, 0, 0, 0, 0,
 383     255, 208, 128, 238, 238, 0, 0, 248, 255, 255, 255, 255, 255, 0, 0, 7, 3,
 384     251, 3, 0, 0, 0, 0, 255, 7, 3, 0, 0, 0, 0, 0, 248, 252, 4,
 385     252, 255, 255, 255, 255, 2, 248, 252, 255, 255, 255, 255, 255
 386 };
 387
 388 static const unsigned char config_pal_rse_info[16] = {
 389     96, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
 390 };
 391
 392 static const unsigned char config_pal_test_info[48] = {
 393     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 394     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 395     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
 396 };
 397
 398 static const unsigned char config_pal_vm_summary[16] = {
 399     101, 18, 15, 2, 7, 7, 4, 2, 59, 18, 0, 0, 0, 0, 0, 0
 400 };
 401
 402 static const unsigned char config_pal_vm_info[104] = {
 403     2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,
 404     32, 32, 0, 0, 0, 0, 0, 0, 112, 85, 21, 0, 0, 0, 0, 0, 0,
 405     0, 0, 0, 0, 0, 0, 1, 32, 32, 0, 0, 0, 0, 0, 0, 112, 85,
 406     21, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 128, 128, 0,
 407     4, 0, 0, 0, 0, 112, 85, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 408     0, 0, 0, 1, 128, 128, 0, 4, 0, 0, 0, 0, 112, 85, 0, 0, 0, 0, 0
 409 };
 410
 411 static const unsigned char config_pal_vm_page_size[16] = {
 412     0, 112, 85, 21, 0, 0, 0, 0, 0, 112, 85, 21, 0, 0, 0, 0
 413 };
 414
 415 typedef struct{
 416     hob_type_t type;
 417     void* data;
 418     unsigned long size;
 419 } hob_batch_t;
 420
 421 static const hob_batch_t hob_batch[]={
 422     {   HOB_TYPE_PAL_BUS_GET_FEATURES_DATA,
 423         &config_pal_bus_get_features_data,
 424         sizeof(config_pal_bus_get_features_data)
 425     },
 426     {   HOB_TYPE_PAL_CACHE_SUMMARY,
 427         &config_pal_cache_summary,
 428         sizeof(config_pal_cache_summary)
 429     },
 430     {   HOB_TYPE_PAL_MEM_ATTRIB,
 431         &config_pal_mem_attrib,
 432         sizeof(config_pal_mem_attrib)
 433     },
 434     {   HOB_TYPE_PAL_CACHE_INFO,
 435         &config_pal_cache_info,
 436         sizeof(config_pal_cache_info)
 437     },
 438     {   HOB_TYPE_PAL_CACHE_PROT_INFO,
 439         &config_pal_cache_prot_info,
 440         sizeof(config_pal_cache_prot_info)
 441     },
 442     {   HOB_TYPE_PAL_DEBUG_INFO,
 443         &config_pal_debug_info,
 444         sizeof(config_pal_debug_info)
 445     },
 446     {   HOB_TYPE_PAL_FIXED_ADDR,
 447         &config_pal_fixed_addr,
 448         sizeof(config_pal_fixed_addr)
 449     },
 450     {   HOB_TYPE_PAL_FREQ_BASE,
 451         &config_pal_freq_base,
 452         sizeof(config_pal_freq_base)
 453     },
 454     {   HOB_TYPE_PAL_FREQ_RATIOS,
 455         &config_pal_freq_ratios,
 456         sizeof(config_pal_freq_ratios)
 457     },
 458     {   HOB_TYPE_PAL_HALT_INFO,
 459         &config_pal_halt_info,
 460         sizeof(config_pal_halt_info)
 461     },
 462     {   HOB_TYPE_PAL_PERF_MON_INFO,
 463         &config_pal_perf_mon_info,
 464         sizeof(config_pal_perf_mon_info)
 465     },
 466     {   HOB_TYPE_PAL_PROC_GET_FEATURES,
 467         &config_pal_proc_get_features,
 468         sizeof(config_pal_proc_get_features)
 469     },
 470     {   HOB_TYPE_PAL_PTCE_INFO,
 471         &config_pal_ptce_info,
 472         sizeof(config_pal_ptce_info)
 473     },
 474     {   HOB_TYPE_PAL_REGISTER_INFO,
 475         &config_pal_register_info,
 476         sizeof(config_pal_register_info)
 477     },
 478     {   HOB_TYPE_PAL_RSE_INFO,
 479         &config_pal_rse_info,
 480         sizeof(config_pal_rse_info)
 481     },
 482     {   HOB_TYPE_PAL_TEST_INFO,
 483         &config_pal_test_info,
 484         sizeof(config_pal_test_info)
 485     },
 486     {   HOB_TYPE_PAL_VM_SUMMARY,
 487         &config_pal_vm_summary,
 488         sizeof(config_pal_vm_summary)
 489     },
 490     {   HOB_TYPE_PAL_VM_INFO,
 491         &config_pal_vm_info,
 492         sizeof(config_pal_vm_info)
 493     },
 494     {   HOB_TYPE_PAL_VM_PAGE_SIZE,
 495         &config_pal_vm_page_size,
 496         sizeof(config_pal_vm_page_size)
 497     },
 498 };
 499
 500 static int
 501 add_pal_hob(void* hob_buf)
 502 {
 503     int i;
 504     for (i = 0; i < sizeof(hob_batch)/sizeof(hob_batch_t); i++) {
 505         if (hob_add(hob_buf, hob_batch[i].type, hob_batch[i].data,
 506                     hob_batch[i].size) < 0)
 507             return -1;
 508     }
 509     return 0;
 510 }
 511 char *read_image(const char *filename, unsigned long *size)
 512 {
 513     int kernel_fd = -1;
 514     gzFile kernel_gfd = NULL;
 515     char *image = NULL, *tmp;
 516     unsigned int bytes;
 517
 518     if ( (filename == NULL) || (size == NULL) )
 519         return NULL;
 520
 521     kernel_fd = open(filename, O_RDONLY);
 522     if (kernel_fd < 0)
 523     {
 524         Hob_Output("Could not open kernel image\n");
 525         goto out_1;
 526     }
 527
 528     if ( (kernel_gfd = gzdopen(kernel_fd, "rb")) == NULL )
 529     {
 530         Hob_Output("Could not allocate decompression state for state file\n");
 531         goto out_1;
 532     }
 533
 534     *size = 0;
 535
 536 #define CHUNK 1*1024*1024
 537     while(1)
 538     {
 539         if ( (tmp = realloc(image, *size + CHUNK)) == NULL )
 540         {
 541             Hob_Output("Could not allocate memory for kernel image");
 542             free(image);
 543             image = NULL;
 544             goto out;
 545         }
 546         image = tmp;
 547
 548         bytes = gzread(kernel_gfd, image + *size, CHUNK);
 549         switch (bytes)
 550         {
 551         case -1:
 552             Hob_Output("Error reading kernel image");
 553             free(image);
 554             image = NULL;
 555             goto out;
 556         case 0: /* EOF */
 557             goto out;
 558         default:
 559             *size += bytes;
 560             break;
 561         }
 562     }
 563 #undef CHUNK
 564
 565  out:
 566     if ( *size == 0 )
 567     {
 568         Hob_Output("Could not read kernel image");
 569         free(image);
 570         image = NULL;
 571     }
 572     else if ( image )
 573     {
 574         /* Shrink allocation to fit image. */
 575         tmp = realloc(image, *size);
 576         if ( tmp )
 577             image = tmp;
 578     }
 579
 580     if ( kernel_gfd != NULL )
 581         gzclose(kernel_gfd);
 582     else if ( kernel_fd >= 0 )
 583         close(kernel_fd);
 584     return image;
 585
 586 out_1:
 587     return NULL;
 588 }
 589
 590 /*
 591  * Local variables:
 592  * mode: C
 593  * c-set-style: "BSD"
 594  * c-basic-offset: 4
 595  * tab-width: 4
 596  * indent-tabs-mode: nil
 597  * End:
 598  */