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         size_t len;
  98         char *savesys_ptr;
  99         char defsys_cmd[DEFSYS_CMD_SIZE];
 100         char savesys_cmd[SAVESYS_CMD_SIZE];
 101
 102         /* Do nothing if we are not running under VM */
 103         if (!MACHINE_IS_VM)
 104                 return;
 105
 106         /* Convert COMMAND_LINE to upper case */
 107         for (i = 0; i < strlen(boot_command_line); i++)
 108                 upper_command_line[i] = toupper(boot_command_line[i]);
 109
 110         savesys_ptr = strstr(upper_command_line, "SAVESYS=");
 111
 112         if (!savesys_ptr)
 113                 return;
 114
 115         savesys_ptr += 8;    /* Point to the beginning of the NSS name */
 116         for (i = 0; i < NSS_NAME_SIZE; i++) {
 117                 if (savesys_ptr[i] == ' ' || savesys_ptr[i] == '\0')
 118                         break;
 119                 kernel_nss_name[i] = savesys_ptr[i];
 120         }
 121
 122         stext_pfn = PFN_DOWN(__pa(&_stext));
 123         eshared_pfn = PFN_DOWN(__pa(&_eshared));
 124         end_pfn = PFN_UP(__pa(&_end));
 125         min_size = end_pfn << 2;
 126
 127         sprintf(defsys_cmd, "DEFSYS %s 00000-%.5X EW %.5X-%.5X SR %.5X-%.5X",
 128                 kernel_nss_name, stext_pfn - 1, stext_pfn, eshared_pfn - 1,
 129                 eshared_pfn, end_pfn);
 130
 131 #ifdef CONFIG_BLK_DEV_INITRD
 132         if (INITRD_START && INITRD_SIZE) {
 133                 sinitrd_pfn = PFN_DOWN(__pa(INITRD_START));
 134                 einitrd_pfn = PFN_UP(__pa(INITRD_START + INITRD_SIZE));
 135                 min_size = einitrd_pfn << 2;
 136                 sprintf(defsys_cmd, "%s EW %.5X-%.5X", defsys_cmd,
 137                 sinitrd_pfn, einitrd_pfn);
 138         }
 139 #endif
 140
 141         sprintf(defsys_cmd, "%s EW MINSIZE=%.7iK PARMREGS=0-13",
 142                 defsys_cmd, min_size);
 143         sprintf(savesys_cmd, "SAVESYS %s \n IPL %s",
 144                 kernel_nss_name, kernel_nss_name);
 145
 146         __cpcmd(defsys_cmd, NULL, 0, &response);
 147
 148         if (response != 0) {
 149                 pr_err("Defining the Linux kernel NSS failed with rc=%d\n",
 150                         response);
 151                 kernel_nss_name[0] = '\0';
 152                 return;
 153         }
 154
 155         len = strlen(savesys_cmd);
 156         ASCEBC(savesys_cmd, len);
 157         response = savesys_ipl_nss(savesys_cmd, len);
 158
 159         /* On success: response is equal to the command size,
 160          *             max SAVESYS_CMD_SIZE
 161          * On error: response contains the numeric portion of cp error message.
 162          *           for SAVESYS it will be >= 263
 163          *           for missing privilege class, it will be 1
 164          */
 165         if (response > SAVESYS_CMD_SIZE || response == 1) {
 166                 pr_err("Saving the Linux kernel NSS failed with rc=%d\n",
 167                         response);
 168                 kernel_nss_name[0] = '\0';
 169                 return;
 170         }
 171
 172         /* re-initialize cputime accounting. */
 173         sched_clock_base_cc = get_clock();
 174         S390_lowcore.last_update_clock = sched_clock_base_cc;
 175         S390_lowcore.last_update_timer = 0x7fffffffffffffffULL;
 176         S390_lowcore.user_timer = 0;
 177         S390_lowcore.system_timer = 0;
 178         asm volatile("SPT 0(%0)" : : "a" (&S390_lowcore.last_update_timer));
 179
 180         /* re-setup boot command line with new ipl vm parms */
 181         ipl_update_parameters();
 182         setup_boot_command_line();
 183
 184         ipl_flags = IPL_NSS_VALID;
 185 }
 186
 187 #else /* CONFIG_SHARED_KERNEL */
 188
 189 static inline void create_kernel_nss(void) { }
 190
 191 #endif /* CONFIG_SHARED_KERNEL */
 192
 193 /*
 194  * Clear bss memory
 195  */
 196 static noinline __init void clear_bss_section(void)
 197 {
 198         memset(__bss_start, 0, __bss_stop - __bss_start);
 199 }
 200
 201 /*
 202  * Initialize storage key for kernel pages
 203  */
 204 static noinline __init void init_kernel_storage_key(void)
 205 {
 206         unsigned long end_pfn, init_pfn;
 207
 208         end_pfn = PFN_UP(__pa(&_end));
 209
 210         for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++)
 211                 page_set_storage_key(init_pfn << PAGE_SHIFT, PAGE_DEFAULT_KEY);
 212 }
 213
 214 static __initdata struct sysinfo_3_2_2 vmms __aligned(PAGE_SIZE);
 215
 216 static noinline __init void detect_machine_type(void)
 217 {
 218         /* Check current-configuration-level */
 219         if ((stsi(NULL, 0, 0, 0) >> 28) <= 2) {
 220                 S390_lowcore.machine_flags |= MACHINE_FLAG_LPAR;
 221                 return;
 222         }
 223         /* Get virtual-machine cpu information. */
 224         if (stsi(&vmms, 3, 2, 2) == -ENOSYS || !vmms.count)
 225                 return;
 226
 227         /* Running under KVM? If not we assume z/VM */
 228         if (!memcmp(vmms.vm[0].cpi, "\xd2\xe5\xd4", 3))
 229                 S390_lowcore.machine_flags |= MACHINE_FLAG_KVM;
 230         else
 231                 S390_lowcore.machine_flags |= MACHINE_FLAG_VM;
 232 }
 233
 234 static __init void early_pgm_check_handler(void)
 235 {
 236         unsigned long addr;
 237         const struct exception_table_entry *fixup;
 238
 239         addr = S390_lowcore.program_old_psw.addr;
 240         fixup = search_exception_tables(addr & PSW_ADDR_INSN);
 241         if (!fixup)
 242                 disabled_wait(0);
 243         S390_lowcore.program_old_psw.addr = fixup->fixup | PSW_ADDR_AMODE;
 244 }
 245
 246 static noinline __init void setup_lowcore_early(void)
 247 {
 248         psw_t psw;
 249
 250         psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
 251         psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_ext_handler;
 252         S390_lowcore.external_new_psw = psw;
 253         psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_pgm_handler;
 254         S390_lowcore.program_new_psw = psw;
 255         s390_base_pgm_handler_fn = early_pgm_check_handler;
 256 }
 257
 258 static noinline __init void setup_hpage(void)
 259 {
 260 #ifndef CONFIG_DEBUG_PAGEALLOC
 261         unsigned int facilities;
 262
 263         facilities = stfl();
 264         if (!(facilities & (1UL << 23)) || !(facilities & (1UL << 29)))
 265                 return;
 266         S390_lowcore.machine_flags |= MACHINE_FLAG_HPAGE;
 267         __ctl_set_bit(0, 23);
 268 #endif
 269 }
 270
 271 static __init void detect_mvpg(void)
 272 {
 273 #ifndef CONFIG_64BIT
 274         int rc;
 275
 276         asm volatile(
 277                 "       la      0,0\n"
 278                 "       mvpg    %2,%2\n"
 279                 "0:     la      %0,0\n"
 280                 "1:\n"
 281                 EX_TABLE(0b,1b)
 282                 : "=d" (rc) : "0" (-EOPNOTSUPP), "a" (0) : "memory", "cc", "0");
 283         if (!rc)
 284                 S390_lowcore.machine_flags |= MACHINE_FLAG_MVPG;
 285 #endif
 286 }
 287
 288 static __init void detect_ieee(void)
 289 {
 290 #ifndef CONFIG_64BIT
 291         int rc, tmp;
 292
 293         asm volatile(
 294                 "       efpc    %1,0\n"
 295                 "0:     la      %0,0\n"
 296                 "1:\n"
 297                 EX_TABLE(0b,1b)
 298                 : "=d" (rc), "=d" (tmp): "0" (-EOPNOTSUPP) : "cc");
 299         if (!rc)
 300                 S390_lowcore.machine_flags |= MACHINE_FLAG_IEEE;
 301 #endif
 302 }
 303
 304 static __init void detect_csp(void)
 305 {
 306 #ifndef CONFIG_64BIT
 307         int rc;
 308
 309         asm volatile(
 310                 "       la      0,0\n"
 311                 "       la      1,0\n"
 312                 "       la      2,4\n"
 313                 "       csp     0,2\n"
 314                 "0:     la      %0,0\n"
 315                 "1:\n"
 316                 EX_TABLE(0b,1b)
 317                 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc", "0", "1", "2");
 318         if (!rc)
 319                 S390_lowcore.machine_flags |= MACHINE_FLAG_CSP;
 320 #endif
 321 }
 322
 323 static __init void detect_diag9c(void)
 324 {
 325         unsigned int cpu_address;
 326         int rc;
 327
 328         cpu_address = stap();
 329         asm volatile(
 330                 "       diag    %2,0,0x9c\n"
 331                 "0:     la      %0,0\n"
 332                 "1:\n"
 333                 EX_TABLE(0b,1b)
 334                 : "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc");
 335         if (!rc)
 336                 S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG9C;
 337 }
 338
 339 static __init void detect_diag44(void)
 340 {
 341 #ifdef CONFIG_64BIT
 342         int rc;
 343
 344         asm volatile(
 345                 "       diag    0,0,0x44\n"
 346                 "0:     la      %0,0\n"
 347                 "1:\n"
 348                 EX_TABLE(0b,1b)
 349                 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc");
 350         if (!rc)
 351                 S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG44;
 352 #endif
 353 }
 354
 355 static __init void detect_machine_facilities(void)
 356 {
 357 #ifdef CONFIG_64BIT
 358         unsigned int facilities;
 359
 360         facilities = stfl();
 361         if (facilities & (1 << 28))
 362                 S390_lowcore.machine_flags |= MACHINE_FLAG_IDTE;
 363         if (facilities & (1 << 23))
 364                 S390_lowcore.machine_flags |= MACHINE_FLAG_PFMF;
 365         if (facilities & (1 << 4))
 366                 S390_lowcore.machine_flags |= MACHINE_FLAG_MVCOS;
 367 #endif
 368 }
 369
 370 static __init void rescue_initrd(void)
 371 {
 372 #ifdef CONFIG_BLK_DEV_INITRD
 373         /*
 374          * Move the initrd right behind the bss section in case it starts
 375          * within the bss section. So we don't overwrite it when the bss
 376          * section gets cleared.
 377          */
 378         if (!INITRD_START || !INITRD_SIZE)
 379                 return;
 380         if (INITRD_START >= (unsigned long) __bss_stop)
 381                 return;
 382         memmove(__bss_stop, (void *) INITRD_START, INITRD_SIZE);
 383         INITRD_START = (unsigned long) __bss_stop;
 384 #endif
 385 }
 386
 387 /* Set up boot command line */
 388 static void __init append_to_cmdline(size_t (*ipl_data)(char *, size_t))
 389 {
 390         char *parm, *delim;
 391         size_t rc, len;
 392
 393         len = strlen(boot_command_line);
 394
 395         delim = boot_command_line + len;        /* '\0' character position */
 396         parm  = boot_command_line + len + 1;    /* append right after '\0' */
 397
 398         rc = ipl_data(parm, COMMAND_LINE_SIZE - len - 1);
 399         if (rc) {
 400                 if (*parm == '=')
 401                         memmove(boot_command_line, parm + 1, rc);
 402                 else
 403                         *delim = ' ';           /* replace '\0' with space */
 404         }
 405 }
 406
 407 static void __init setup_boot_command_line(void)
 408 {
 409         int i;
 410
 411         /* convert arch command line to ascii */
 412         for (i = 0; i < ARCH_COMMAND_LINE_SIZE; i++)
 413                 if (COMMAND_LINE[i] & 0x80)
 414                         break;
 415         if (i < ARCH_COMMAND_LINE_SIZE)
 416                 EBCASC(COMMAND_LINE, ARCH_COMMAND_LINE_SIZE);
 417         COMMAND_LINE[ARCH_COMMAND_LINE_SIZE-1] = 0;
 418
 419         /* copy arch command line */
 420         strlcpy(boot_command_line, strstrip(COMMAND_LINE),
 421                 ARCH_COMMAND_LINE_SIZE);
 422
 423         /* append IPL PARM data to the boot command line */
 424         if (MACHINE_IS_VM)
 425                 append_to_cmdline(append_ipl_vmparm);
 426
 427         append_to_cmdline(append_ipl_scpdata);
 428 }
 429
 430
 431 /*
 432  * Save ipl parameters, clear bss memory, initialize storage keys
 433  * and create a kernel NSS at startup if the SAVESYS= parm is defined
 434  */
 435 void __init startup_init(void)
 436 {
 437         reset_tod_clock();
 438         ipl_save_parameters();
 439         rescue_initrd();
 440         clear_bss_section();
 441         init_kernel_storage_key();
 442         lockdep_init();
 443         lockdep_off();
 444         sort_main_extable();
 445         setup_lowcore_early();
 446         detect_machine_type();
 447         ipl_update_parameters();
 448         setup_boot_command_line();
 449         create_kernel_nss();
 450         detect_mvpg();
 451         detect_ieee();
 452         detect_csp();
 453         detect_diag9c();
 454         detect_diag44();
 455         detect_machine_facilities();
 456         setup_hpage();
 457         sclp_facilities_detect();
 458         detect_memory_layout(memory_chunk);
 459 #ifdef CONFIG_DYNAMIC_FTRACE
 460         S390_lowcore.ftrace_func = (unsigned long)ftrace_caller;
 461 #endif
 462         lockdep_on();
 463 }