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