arch/s390/kernel/early.c

   1 /*
   2  *  arch/s390/kernel/early.c
   3  *
   4  *    Copyright IBM Corp. 2007, 2009
   5  *    Author(s): Hongjie Yang <hongjie@us.ibm.com>,
   6  *               Heiko Carstens <heiko.carstens@de.ibm.com>
   7  */
   8
   9 #define KMSG_COMPONENT "setup"
  10 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  11
  12 #include <linux/compiler.h>
  13 #include <linux/init.h>
  14 #include <linux/errno.h>
  15 #include <linux/string.h>
  16 #include <linux/ctype.h>
  17 #include <linux/ftrace.h>
  18 #include <linux/lockdep.h>
  19 #include <linux/module.h>
  20 #include <linux/pfn.h>
  21 #include <linux/uaccess.h>
  22 #include <linux/kernel.h>
  23 #include <asm/ebcdic.h>
  24 #include <asm/ipl.h>
  25 #include <asm/lowcore.h>
  26 #include <asm/processor.h>
  27 #include <asm/sections.h>
  28 #include <asm/setup.h>
  29 #include <asm/sysinfo.h>
  30 #include <asm/cpcmd.h>
  31 #include <asm/sclp.h>
  32 #include "entry.h"
  33
  34 /*
  35  * Create a Kernel NSS if the SAVESYS= parameter is defined
  36  */
  37 #define DEFSYS_CMD_SIZE         128
  38 #define SAVESYS_CMD_SIZE        32
  39
  40 char kernel_nss_name[NSS_NAME_SIZE + 1];
  41
  42 static void __init setup_boot_command_line(void);
  43
  44 /*
  45  * Get the TOD clock running.
  46  */
  47 static void __init reset_tod_clock(void)
  48 {
  49         u64 time;
  50
  51         if (store_clock(&time) == 0)
  52                 return;
  53         /* TOD clock not running. Set the clock to Unix Epoch. */
  54         if (set_clock(TOD_UNIX_EPOCH) != 0 || store_clock(&time) != 0)
  55                 disabled_wait(0);
  56
  57         sched_clock_base_cc = TOD_UNIX_EPOCH;
  58         S390_lowcore.last_update_clock = sched_clock_base_cc;
  59 }
  60
  61 #ifdef CONFIG_SHARED_KERNEL
  62 int __init savesys_ipl_nss(char *cmd, const int cmdlen);
  63
  64 asm(
  65         "       .section .init.text,\"ax\",@progbits\n"
  66         "       .align  4\n"
  67         "       .type   savesys_ipl_nss, @function\n"
  68         "savesys_ipl_nss:\n"
  69 #ifdef CONFIG_64BIT
  70         "       stmg    6,15,48(15)\n"
  71         "       lgr     14,3\n"
  72         "       sam31\n"
  73         "       diag    2,14,0x8\n"
  74         "       sam64\n"
  75         "       lgr     2,14\n"
  76         "       lmg     6,15,48(15)\n"
  77 #else
  78         "       stm     6,15,24(15)\n"
  79         "       lr      14,3\n"
  80         "       diag    2,14,0x8\n"
  81         "       lr      2,14\n"
  82         "       lm      6,15,24(15)\n"
  83 #endif
  84         "       br      14\n"
  85         "       .size   savesys_ipl_nss, .-savesys_ipl_nss\n"
  86         "       .previous\n");
  87
  88 static __initdata char upper_command_line[COMMAND_LINE_SIZE];
  89
  90 static noinline __init void create_kernel_nss(void)
  91 {
  92         unsigned int i, stext_pfn, eshared_pfn, end_pfn, min_size;
  93 #ifdef CONFIG_BLK_DEV_INITRD
  94         unsigned int sinitrd_pfn, einitrd_pfn;
  95 #endif
  96         int response;
  97         int hlen;
  98         size_t len;
  99         char *savesys_ptr;
 100         char defsys_cmd[DEFSYS_CMD_SIZE];
 101         char savesys_cmd[SAVESYS_CMD_SIZE];
 102
 103         /* Do nothing if we are not running under VM */
 104         if (!MACHINE_IS_VM)
 105                 return;
 106
 107         /* Convert COMMAND_LINE to upper case */
 108         for (i = 0; i < strlen(boot_command_line); i++)
 109                 upper_command_line[i] = toupper(boot_command_line[i]);
 110
 111         savesys_ptr = strstr(upper_command_line, "SAVESYS=");
 112
 113         if (!savesys_ptr)
 114                 return;
 115
 116         savesys_ptr += 8;    /* Point to the beginning of the NSS name */
 117         for (i = 0; i < NSS_NAME_SIZE; i++) {
 118                 if (savesys_ptr[i] == ' ' || savesys_ptr[i] == '\0')
 119                         break;
 120                 kernel_nss_name[i] = savesys_ptr[i];
 121         }
 122
 123         stext_pfn = PFN_DOWN(__pa(&_stext));
 124         eshared_pfn = PFN_DOWN(__pa(&_eshared));
 125         end_pfn = PFN_UP(__pa(&_end));
 126         min_size = end_pfn << 2;
 127
 128         hlen = snprintf(defsys_cmd, DEFSYS_CMD_SIZE,
 129                         "DEFSYS %s 00000-%.5X EW %.5X-%.5X SR %.5X-%.5X",
 130                         kernel_nss_name, stext_pfn - 1, stext_pfn,
 131                         eshared_pfn - 1, eshared_pfn, end_pfn);
 132
 133 #ifdef CONFIG_BLK_DEV_INITRD
 134         if (INITRD_START && INITRD_SIZE) {
 135                 sinitrd_pfn = PFN_DOWN(__pa(INITRD_START));
 136                 einitrd_pfn = PFN_UP(__pa(INITRD_START + INITRD_SIZE));
 137                 min_size = einitrd_pfn << 2;
 138                 hlen += snprintf(defsys_cmd + hlen, DEFSYS_CMD_SIZE - hlen,
 139                                  " EW %.5X-%.5X", sinitrd_pfn, einitrd_pfn);
 140         }
 141 #endif
 142
 143         snprintf(defsys_cmd + hlen, DEFSYS_CMD_SIZE - hlen,
 144                  " EW MINSIZE=%.7iK PARMREGS=0-13", min_size);
 145         defsys_cmd[DEFSYS_CMD_SIZE - 1] = '\0';
 146         snprintf(savesys_cmd, SAVESYS_CMD_SIZE, "SAVESYS %s \n IPL %s",
 147                  kernel_nss_name, kernel_nss_name);
 148         savesys_cmd[SAVESYS_CMD_SIZE - 1] = '\0';
 149
 150         __cpcmd(defsys_cmd, NULL, 0, &response);
 151
 152         if (response != 0) {
 153                 pr_err("Defining the Linux kernel NSS failed with rc=%d\n",
 154                         response);
 155                 kernel_nss_name[0] = '\0';
 156                 return;
 157         }
 158
 159         len = strlen(savesys_cmd);
 160         ASCEBC(savesys_cmd, len);
 161         response = savesys_ipl_nss(savesys_cmd, len);
 162
 163         /* On success: response is equal to the command size,
 164          *             max SAVESYS_CMD_SIZE
 165          * On error: response contains the numeric portion of cp error message.
 166          *           for SAVESYS it will be >= 263
 167          *           for missing privilege class, it will be 1
 168          */
 169         if (response > SAVESYS_CMD_SIZE || response == 1) {
 170                 pr_err("Saving the Linux kernel NSS failed with rc=%d\n",
 171                         response);
 172                 kernel_nss_name[0] = '\0';
 173                 return;
 174         }
 175
 176         /* re-initialize cputime accounting. */
 177         sched_clock_base_cc = get_clock();
 178         S390_lowcore.last_update_clock = sched_clock_base_cc;
 179         S390_lowcore.last_update_timer = 0x7fffffffffffffffULL;
 180         S390_lowcore.user_timer = 0;
 181         S390_lowcore.system_timer = 0;
 182         asm volatile("SPT 0(%0)" : : "a" (&S390_lowcore.last_update_timer));
 183
 184         /* re-setup boot command line with new ipl vm parms */
 185         ipl_update_parameters();
 186         setup_boot_command_line();
 187
 188         ipl_flags = IPL_NSS_VALID;
 189 }
 190
 191 #else /* CONFIG_SHARED_KERNEL */
 192
 193 static inline void create_kernel_nss(void) { }
 194
 195 #endif /* CONFIG_SHARED_KERNEL */
 196
 197 /*
 198  * Clear bss memory
 199  */
 200 static noinline __init void clear_bss_section(void)
 201 {
 202         memset(__bss_start, 0, __bss_stop - __bss_start);
 203 }
 204
 205 /*
 206  * Initialize storage key for kernel pages
 207  */
 208 static noinline __init void init_kernel_storage_key(void)
 209 {
 210         unsigned long end_pfn, init_pfn;
 211
 212         end_pfn = PFN_UP(__pa(&_end));
 213
 214         for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++)
 215                 page_set_storage_key(init_pfn << PAGE_SHIFT,
 216                                      PAGE_DEFAULT_KEY, 0);
 217 }
 218
 219 static __initdata struct sysinfo_3_2_2 vmms __aligned(PAGE_SIZE);
 220
 221 static noinline __init void detect_machine_type(void)
 222 {
 223         /* Check current-configuration-level */
 224         if ((stsi(NULL, 0, 0, 0) >> 28) <= 2) {
 225                 S390_lowcore.machine_flags |= MACHINE_FLAG_LPAR;
 226                 return;
 227         }
 228         /* Get virtual-machine cpu information. */
 229         if (stsi(&vmms, 3, 2, 2) == -ENOSYS || !vmms.count)
 230                 return;
 231
 232         /* Running under KVM? If not we assume z/VM */
 233         if (!memcmp(vmms.vm[0].cpi, "\xd2\xe5\xd4", 3))
 234                 S390_lowcore.machine_flags |= MACHINE_FLAG_KVM;
 235         else
 236                 S390_lowcore.machine_flags |= MACHINE_FLAG_VM;
 237 }
 238
 239 static __init void early_pgm_check_handler(void)
 240 {
 241         unsigned long addr;
 242         const struct exception_table_entry *fixup;
 243
 244         addr = S390_lowcore.program_old_psw.addr;
 245         fixup = search_exception_tables(addr & PSW_ADDR_INSN);
 246         if (!fixup)
 247                 disabled_wait(0);
 248         S390_lowcore.program_old_psw.addr = fixup->fixup | PSW_ADDR_AMODE;
 249 }
 250
 251 static noinline __init void setup_lowcore_early(void)
 252 {
 253         psw_t psw;
 254
 255         psw.mask = PSW_MASK_BASE | PSW_DEFAULT_KEY | PSW_MASK_EA | PSW_MASK_BA;
 256         psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_ext_handler;
 257         S390_lowcore.external_new_psw = psw;
 258         psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_pgm_handler;
 259         S390_lowcore.program_new_psw = psw;
 260         s390_base_pgm_handler_fn = early_pgm_check_handler;
 261 }
 262
 263 static noinline __init void setup_facility_list(void)
 264 {
 265         unsigned long nr;
 266
 267         S390_lowcore.stfl_fac_list = 0;
 268         asm volatile(
 269                 "       .insn   s,0xb2b10000,0(0)\n" /* stfl */
 270                 "0:\n"
 271                 EX_TABLE(0b,0b) : "=m" (S390_lowcore.stfl_fac_list));
 272         memcpy(&S390_lowcore.stfle_fac_list, &S390_lowcore.stfl_fac_list, 4);
 273         nr = 4;                         /* # bytes stored by stfl */
 274         if (test_facility(7)) {
 275                 /* More facility bits available with stfle */
 276                 register unsigned long reg0 asm("0") = MAX_FACILITY_BIT/64 - 1;
 277                 asm volatile(".insn s,0xb2b00000,%0" /* stfle */
 278                              : "=m" (S390_lowcore.stfle_fac_list), "+d" (reg0)
 279                              : : "cc");
 280                 nr = (reg0 + 1) * 8;    /* # bytes stored by stfle */
 281         }
 282         memset((char *) S390_lowcore.stfle_fac_list + nr, 0,
 283                MAX_FACILITY_BIT/8 - nr);
 284 }
 285
 286 static noinline __init void setup_hpage(void)
 287 {
 288 #ifndef CONFIG_DEBUG_PAGEALLOC
 289         if (!test_facility(2) || !test_facility(8))
 290                 return;
 291         S390_lowcore.machine_flags |= MACHINE_FLAG_HPAGE;
 292         __ctl_set_bit(0, 23);
 293 #endif
 294 }
 295
 296 static __init void detect_mvpg(void)
 297 {
 298 #ifndef CONFIG_64BIT
 299         int rc;
 300
 301         asm volatile(
 302                 "       la      0,0\n"
 303                 "       mvpg    %2,%2\n"
 304                 "0:     la      %0,0\n"
 305                 "1:\n"
 306                 EX_TABLE(0b,1b)
 307                 : "=d" (rc) : "0" (-EOPNOTSUPP), "a" (0) : "memory", "cc", "0");
 308         if (!rc)
 309                 S390_lowcore.machine_flags |= MACHINE_FLAG_MVPG;
 310 #endif
 311 }
 312
 313 static __init void detect_ieee(void)
 314 {
 315 #ifndef CONFIG_64BIT
 316         int rc, tmp;
 317
 318         asm volatile(
 319                 "       efpc    %1,0\n"
 320                 "0:     la      %0,0\n"
 321                 "1:\n"
 322                 EX_TABLE(0b,1b)
 323                 : "=d" (rc), "=d" (tmp): "0" (-EOPNOTSUPP) : "cc");
 324         if (!rc)
 325                 S390_lowcore.machine_flags |= MACHINE_FLAG_IEEE;
 326 #endif
 327 }
 328
 329 static __init void detect_csp(void)
 330 {
 331 #ifndef CONFIG_64BIT
 332         int rc;
 333
 334         asm volatile(
 335                 "       la      0,0\n"
 336                 "       la      1,0\n"
 337                 "       la      2,4\n"
 338                 "       csp     0,2\n"
 339                 "0:     la      %0,0\n"
 340                 "1:\n"
 341                 EX_TABLE(0b,1b)
 342                 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc", "0", "1", "2");
 343         if (!rc)
 344                 S390_lowcore.machine_flags |= MACHINE_FLAG_CSP;
 345 #endif
 346 }
 347
 348 static __init void detect_diag9c(void)
 349 {
 350         unsigned int cpu_address;
 351         int rc;
 352
 353         cpu_address = stap();
 354         asm volatile(
 355                 "       diag    %2,0,0x9c\n"
 356                 "0:     la      %0,0\n"
 357                 "1:\n"
 358                 EX_TABLE(0b,1b)
 359                 : "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc");
 360         if (!rc)
 361                 S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG9C;
 362 }
 363
 364 static __init void detect_diag44(void)
 365 {
 366 #ifdef CONFIG_64BIT
 367         int rc;
 368
 369         asm volatile(
 370                 "       diag    0,0,0x44\n"
 371                 "0:     la      %0,0\n"
 372                 "1:\n"
 373                 EX_TABLE(0b,1b)
 374                 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc");
 375         if (!rc)
 376                 S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG44;
 377 #endif
 378 }
 379
 380 static __init void detect_machine_facilities(void)
 381 {
 382 #ifdef CONFIG_64BIT
 383         if (test_facility(3))
 384                 S390_lowcore.machine_flags |= MACHINE_FLAG_IDTE;
 385         if (test_facility(8))
 386                 S390_lowcore.machine_flags |= MACHINE_FLAG_PFMF;
 387         if (test_facility(11))
 388                 S390_lowcore.machine_flags |= MACHINE_FLAG_TOPOLOGY;
 389         if (test_facility(27))
 390                 S390_lowcore.machine_flags |= MACHINE_FLAG_MVCOS;
 391         if (test_facility(40))
 392                 S390_lowcore.machine_flags |= MACHINE_FLAG_SPP;
 393         if (test_facility(25))
 394                 S390_lowcore.machine_flags |= MACHINE_FLAG_STCKF;
 395 #endif
 396 }
 397
 398 static __init void rescue_initrd(void)
 399 {
 400 #ifdef CONFIG_BLK_DEV_INITRD
 401         unsigned long min_initrd_addr = (unsigned long) _end + (4UL << 20);
 402         /*
 403          * Just like in case of IPL from VM reader we make sure there is a
 404          * gap of 4MB between end of kernel and start of initrd.
 405          * That way we can also be sure that saving an NSS will succeed,
 406          * which however only requires different segments.
 407          */
 408         if (!INITRD_START || !INITRD_SIZE)
 409                 return;
 410         if (INITRD_START >= min_initrd_addr)
 411                 return;
 412         memmove((void *) min_initrd_addr, (void *) INITRD_START, INITRD_SIZE);
 413         INITRD_START = min_initrd_addr;
 414 #endif
 415 }
 416
 417 /* Set up boot command line */
 418 static void __init append_to_cmdline(size_t (*ipl_data)(char *, size_t))
 419 {
 420         char *parm, *delim;
 421         size_t rc, len;
 422
 423         len = strlen(boot_command_line);
 424
 425         delim = boot_command_line + len;        /* '\0' character position */
 426         parm  = boot_command_line + len + 1;    /* append right after '\0' */
 427
 428         rc = ipl_data(parm, COMMAND_LINE_SIZE - len - 1);
 429         if (rc) {
 430                 if (*parm == '=')
 431                         memmove(boot_command_line, parm + 1, rc);
 432                 else
 433                         *delim = ' ';           /* replace '\0' with space */
 434         }
 435 }
 436
 437 static inline int has_ebcdic_char(const char *str)
 438 {
 439         int i;
 440
 441         for (i = 0; str[i]; i++)
 442                 if (str[i] & 0x80)
 443                         return 1;
 444         return 0;
 445 }
 446
 447 static void __init setup_boot_command_line(void)
 448 {
 449         COMMAND_LINE[ARCH_COMMAND_LINE_SIZE - 1] = 0;
 450         /* convert arch command line to ascii if necessary */
 451         if (has_ebcdic_char(COMMAND_LINE))
 452                 EBCASC(COMMAND_LINE, ARCH_COMMAND_LINE_SIZE);
 453         /* copy arch command line */
 454         strlcpy(boot_command_line, strstrip(COMMAND_LINE),
 455                 ARCH_COMMAND_LINE_SIZE);
 456
 457         /* append IPL PARM data to the boot command line */
 458         if (MACHINE_IS_VM)
 459                 append_to_cmdline(append_ipl_vmparm);
 460
 461         append_to_cmdline(append_ipl_scpdata);
 462 }
 463
 464
 465 /*
 466  * Save ipl parameters, clear bss memory, initialize storage keys
 467  * and create a kernel NSS at startup if the SAVESYS= parm is defined
 468  */
 469 void __init startup_init(void)
 470 {
 471         reset_tod_clock();
 472         ipl_save_parameters();
 473         rescue_initrd();
 474         clear_bss_section();
 475         init_kernel_storage_key();
 476         lockdep_init();
 477         lockdep_off();
 478         sort_main_extable();
 479         setup_lowcore_early();
 480         setup_facility_list();
 481         detect_machine_type();
 482         ipl_update_parameters();
 483         setup_boot_command_line();
 484         create_kernel_nss();
 485         detect_mvpg();
 486         detect_ieee();
 487         detect_csp();
 488         detect_diag9c();
 489         detect_diag44();
 490         detect_machine_facilities();
 491         setup_hpage();
 492         sclp_facilities_detect();
 493         detect_memory_layout(memory_chunk);
 494 #ifdef CONFIG_DYNAMIC_FTRACE
 495         S390_lowcore.ftrace_func = (unsigned long)ftrace_caller;
 496 #endif
 497         lockdep_on();
 498 }