kernel/arch/s390/kernel/early.c

   1 /*
   2  *    Copyright IBM Corp. 2007, 2009
   3  *    Author(s): Hongjie Yang <hongjie@us.ibm.com>,
   4  *               Heiko Carstens <heiko.carstens@de.ibm.com>
   5  */
   6
   7 #define KMSG_COMPONENT "setup"
   8 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
   9
  10 #include <linux/compiler.h>
  11 #include <linux/init.h>
  12 #include <linux/errno.h>
  13 #include <linux/string.h>
  14 #include <linux/ctype.h>
  15 #include <linux/lockdep.h>
  16 #include <linux/module.h>
  17 #include <linux/pfn.h>
  18 #include <linux/uaccess.h>
  19 #include <linux/kernel.h>
  20 #include <asm/ebcdic.h>
  21 #include <asm/ipl.h>
  22 #include <asm/lowcore.h>
  23 #include <asm/processor.h>
  24 #include <asm/sections.h>
  25 #include <asm/setup.h>
  26 #include <asm/sysinfo.h>
  27 #include <asm/cpcmd.h>
  28 #include <asm/sclp.h>
  29 #include <asm/facility.h>
  30 #include "entry.h"
  31
  32 /*
  33  * Create a Kernel NSS if the SAVESYS= parameter is defined
  34  */
  35 #define DEFSYS_CMD_SIZE         128
  36 #define SAVESYS_CMD_SIZE        32
  37
  38 char kernel_nss_name[NSS_NAME_SIZE + 1];
  39
  40 static void __init setup_boot_command_line(void);
  41
  42 /*
  43  * Get the TOD clock running.
  44  */
  45 static void __init reset_tod_clock(void)
  46 {
  47         u64 time;
  48
  49         if (store_tod_clock(&time) == 0)
  50                 return;
  51         /* TOD clock not running. Set the clock to Unix Epoch. */
  52         if (set_tod_clock(TOD_UNIX_EPOCH) != 0 || store_tod_clock(&time) != 0)
  53                 disabled_wait(0);
  54
  55         sched_clock_base_cc = TOD_UNIX_EPOCH;
  56         S390_lowcore.last_update_clock = sched_clock_base_cc;
  57 }
  58
  59 #ifdef CONFIG_SHARED_KERNEL
  60 int __init savesys_ipl_nss(char *cmd, const int cmdlen);
  61
  62 asm(
  63         "       .section .init.text,\"ax\",@progbits\n"
  64         "       .align  4\n"
  65         "       .type   savesys_ipl_nss, @function\n"
  66         "savesys_ipl_nss:\n"
  67         "       stmg    6,15,48(15)\n"
  68         "       lgr     14,3\n"
  69         "       sam31\n"
  70         "       diag    2,14,0x8\n"
  71         "       sam64\n"
  72         "       lgr     2,14\n"
  73         "       lmg     6,15,48(15)\n"
  74         "       br      14\n"
  75         "       .size   savesys_ipl_nss, .-savesys_ipl_nss\n"
  76         "       .previous\n");
  77
  78 static __initdata char upper_command_line[COMMAND_LINE_SIZE];
  79
  80 static noinline __init void create_kernel_nss(void)
  81 {
  82         unsigned int i, stext_pfn, eshared_pfn, end_pfn, min_size;
  83 #ifdef CONFIG_BLK_DEV_INITRD
  84         unsigned int sinitrd_pfn, einitrd_pfn;
  85 #endif
  86         int response;
  87         int hlen;
  88         size_t len;
  89         char *savesys_ptr;
  90         char defsys_cmd[DEFSYS_CMD_SIZE];
  91         char savesys_cmd[SAVESYS_CMD_SIZE];
  92
  93         /* Do nothing if we are not running under VM */
  94         if (!MACHINE_IS_VM)
  95                 return;
  96
  97         /* Convert COMMAND_LINE to upper case */
  98         for (i = 0; i < strlen(boot_command_line); i++)
  99                 upper_command_line[i] = toupper(boot_command_line[i]);
 100
 101         savesys_ptr = strstr(upper_command_line, "SAVESYS=");
 102
 103         if (!savesys_ptr)
 104                 return;
 105
 106         savesys_ptr += 8;    /* Point to the beginning of the NSS name */
 107         for (i = 0; i < NSS_NAME_SIZE; i++) {
 108                 if (savesys_ptr[i] == ' ' || savesys_ptr[i] == '\0')
 109                         break;
 110                 kernel_nss_name[i] = savesys_ptr[i];
 111         }
 112
 113         stext_pfn = PFN_DOWN(__pa(&_stext));
 114         eshared_pfn = PFN_DOWN(__pa(&_eshared));
 115         end_pfn = PFN_UP(__pa(&_end));
 116         min_size = end_pfn << 2;
 117
 118         hlen = snprintf(defsys_cmd, DEFSYS_CMD_SIZE,
 119                         "DEFSYS %s 00000-%.5X EW %.5X-%.5X SR %.5X-%.5X",
 120                         kernel_nss_name, stext_pfn - 1, stext_pfn,
 121                         eshared_pfn - 1, eshared_pfn, end_pfn);
 122
 123 #ifdef CONFIG_BLK_DEV_INITRD
 124         if (INITRD_START && INITRD_SIZE) {
 125                 sinitrd_pfn = PFN_DOWN(__pa(INITRD_START));
 126                 einitrd_pfn = PFN_UP(__pa(INITRD_START + INITRD_SIZE));
 127                 min_size = einitrd_pfn << 2;
 128                 hlen += snprintf(defsys_cmd + hlen, DEFSYS_CMD_SIZE - hlen,
 129                                  " EW %.5X-%.5X", sinitrd_pfn, einitrd_pfn);
 130         }
 131 #endif
 132
 133         snprintf(defsys_cmd + hlen, DEFSYS_CMD_SIZE - hlen,
 134                  " EW MINSIZE=%.7iK PARMREGS=0-13", min_size);
 135         defsys_cmd[DEFSYS_CMD_SIZE - 1] = '\0';
 136         snprintf(savesys_cmd, SAVESYS_CMD_SIZE, "SAVESYS %s \n IPL %s",
 137                  kernel_nss_name, kernel_nss_name);
 138         savesys_cmd[SAVESYS_CMD_SIZE - 1] = '\0';
 139
 140         __cpcmd(defsys_cmd, NULL, 0, &response);
 141
 142         if (response != 0) {
 143                 pr_err("Defining the Linux kernel NSS failed with rc=%d\n",
 144                         response);
 145                 kernel_nss_name[0] = '\0';
 146                 return;
 147         }
 148
 149         len = strlen(savesys_cmd);
 150         ASCEBC(savesys_cmd, len);
 151         response = savesys_ipl_nss(savesys_cmd, len);
 152
 153         /* On success: response is equal to the command size,
 154          *             max SAVESYS_CMD_SIZE
 155          * On error: response contains the numeric portion of cp error message.
 156          *           for SAVESYS it will be >= 263
 157          *           for missing privilege class, it will be 1
 158          */
 159         if (response > SAVESYS_CMD_SIZE || response == 1) {
 160                 pr_err("Saving the Linux kernel NSS failed with rc=%d\n",
 161                         response);
 162                 kernel_nss_name[0] = '\0';
 163                 return;
 164         }
 165
 166         /* re-initialize cputime accounting. */
 167         sched_clock_base_cc = get_tod_clock();
 168         S390_lowcore.last_update_clock = sched_clock_base_cc;
 169         S390_lowcore.last_update_timer = 0x7fffffffffffffffULL;
 170         S390_lowcore.user_timer = 0;
 171         S390_lowcore.system_timer = 0;
 172         asm volatile("SPT 0(%0)" : : "a" (&S390_lowcore.last_update_timer));
 173
 174         /* re-setup boot command line with new ipl vm parms */
 175         ipl_update_parameters();
 176         setup_boot_command_line();
 177
 178         ipl_flags = IPL_NSS_VALID;
 179 }
 180
 181 #else /* CONFIG_SHARED_KERNEL */
 182
 183 static inline void create_kernel_nss(void) { }
 184
 185 #endif /* CONFIG_SHARED_KERNEL */
 186
 187 /*
 188  * Clear bss memory
 189  */
 190 static noinline __init void clear_bss_section(void)
 191 {
 192         memset(__bss_start, 0, __bss_stop - __bss_start);
 193 }
 194
 195 /*
 196  * Initialize storage key for kernel pages
 197  */
 198 static noinline __init void init_kernel_storage_key(void)
 199 {
 200 #if PAGE_DEFAULT_KEY
 201         unsigned long end_pfn, init_pfn;
 202
 203         end_pfn = PFN_UP(__pa(&_end));
 204
 205         for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++)
 206                 page_set_storage_key(init_pfn << PAGE_SHIFT,
 207                                      PAGE_DEFAULT_KEY, 0);
 208 #endif
 209 }
 210
 211 static __initdata char sysinfo_page[PAGE_SIZE] __aligned(PAGE_SIZE);
 212
 213 static noinline __init void detect_machine_type(void)
 214 {
 215         struct sysinfo_3_2_2 *vmms = (struct sysinfo_3_2_2 *)&sysinfo_page;
 216
 217         /* Check current-configuration-level */
 218         if (stsi(NULL, 0, 0, 0) <= 2) {
 219                 S390_lowcore.machine_flags |= MACHINE_FLAG_LPAR;
 220                 return;
 221         }
 222         /* Get virtual-machine cpu information. */
 223         if (stsi(vmms, 3, 2, 2) || !vmms->count)
 224                 return;
 225
 226         /* Running under KVM? If not we assume z/VM */
 227         if (!memcmp(vmms->vm[0].cpi, "\xd2\xe5\xd4", 3))
 228                 S390_lowcore.machine_flags |= MACHINE_FLAG_KVM;
 229         else
 230                 S390_lowcore.machine_flags |= MACHINE_FLAG_VM;
 231 }
 232
 233 static __init void setup_topology(void)
 234 {
 235         int max_mnest;
 236
 237         if (!test_facility(11))
 238                 return;
 239         S390_lowcore.machine_flags |= MACHINE_FLAG_TOPOLOGY;
 240         for (max_mnest = 6; max_mnest > 1; max_mnest--) {
 241                 if (stsi(&sysinfo_page, 15, 1, max_mnest) == 0)
 242                         break;
 243         }
 244         topology_max_mnest = max_mnest;
 245 }
 246
 247 static void early_pgm_check_handler(void)
 248 {
 249         const struct exception_table_entry *fixup;
 250         unsigned long cr0, cr0_new;
 251         unsigned long addr;
 252
 253         addr = S390_lowcore.program_old_psw.addr;
 254         fixup = search_exception_tables(addr & PSW_ADDR_INSN);
 255         if (!fixup)
 256                 disabled_wait(0);
 257         /* Disable low address protection before storing into lowcore. */
 258         __ctl_store(cr0, 0, 0);
 259         cr0_new = cr0 & ~(1UL << 28);
 260         __ctl_load(cr0_new, 0, 0);
 261         S390_lowcore.program_old_psw.addr = extable_fixup(fixup)|PSW_ADDR_AMODE;
 262         __ctl_load(cr0, 0, 0);
 263 }
 264
 265 static noinline __init void setup_lowcore_early(void)
 266 {
 267         psw_t psw;
 268
 269         psw.mask = PSW_MASK_BASE | PSW_DEFAULT_KEY | PSW_MASK_EA | PSW_MASK_BA;
 270         psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_ext_handler;
 271         S390_lowcore.external_new_psw = psw;
 272         psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_pgm_handler;
 273         S390_lowcore.program_new_psw = psw;
 274         s390_base_pgm_handler_fn = early_pgm_check_handler;
 275 }
 276
 277 static noinline __init void setup_facility_list(void)
 278 {
 279         stfle(S390_lowcore.stfle_fac_list,
 280               ARRAY_SIZE(S390_lowcore.stfle_fac_list));
 281 }
 282
 283 static __init void detect_diag9c(void)
 284 {
 285         unsigned int cpu_address;
 286         int rc;
 287
 288         cpu_address = stap();
 289         asm volatile(
 290                 "       diag    %2,0,0x9c\n"
 291                 "0:     la      %0,0\n"
 292                 "1:\n"
 293                 EX_TABLE(0b,1b)
 294                 : "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc");
 295         if (!rc)
 296                 S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG9C;
 297 }
 298
 299 static __init void detect_diag44(void)
 300 {
 301         int rc;
 302
 303         asm volatile(
 304                 "       diag    0,0,0x44\n"
 305                 "0:     la      %0,0\n"
 306                 "1:\n"
 307                 EX_TABLE(0b,1b)
 308                 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc");
 309         if (!rc)
 310                 S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG44;
 311 }
 312
 313 static __init void detect_machine_facilities(void)
 314 {
 315         if (test_facility(8)) {
 316                 S390_lowcore.machine_flags |= MACHINE_FLAG_EDAT1;
 317                 __ctl_set_bit(0, 23);
 318         }
 319         if (test_facility(78))
 320                 S390_lowcore.machine_flags |= MACHINE_FLAG_EDAT2;
 321         if (test_facility(3))
 322                 S390_lowcore.machine_flags |= MACHINE_FLAG_IDTE;
 323         if (test_facility(40))
 324                 S390_lowcore.machine_flags |= MACHINE_FLAG_LPP;
 325         if (test_facility(50) && test_facility(73))
 326                 S390_lowcore.machine_flags |= MACHINE_FLAG_TE;
 327         if (test_facility(51))
 328                 S390_lowcore.machine_flags |= MACHINE_FLAG_TLB_LC;
 329         if (test_facility(129))
 330                 S390_lowcore.machine_flags |= MACHINE_FLAG_VX;
 331 }
 332
 333 static int __init cad_setup(char *str)
 334 {
 335         int val;
 336
 337         get_option(&str, &val);
 338         if (val && test_facility(128))
 339                 S390_lowcore.machine_flags |= MACHINE_FLAG_CAD;
 340         return 0;
 341 }
 342 early_param("cad", cad_setup);
 343
 344 static int __init cad_init(void)
 345 {
 346         if (MACHINE_HAS_CAD)
 347                 /* Enable problem state CAD. */
 348                 __ctl_set_bit(2, 3);
 349         return 0;
 350 }
 351 early_initcall(cad_init);
 352
 353 static __init void rescue_initrd(void)
 354 {
 355 #ifdef CONFIG_BLK_DEV_INITRD
 356         unsigned long min_initrd_addr = (unsigned long) _end + (4UL << 20);
 357         /*
 358          * Just like in case of IPL from VM reader we make sure there is a
 359          * gap of 4MB between end of kernel and start of initrd.
 360          * That way we can also be sure that saving an NSS will succeed,
 361          * which however only requires different segments.
 362          */
 363         if (!INITRD_START || !INITRD_SIZE)
 364                 return;
 365         if (INITRD_START >= min_initrd_addr)
 366                 return;
 367         memmove((void *) min_initrd_addr, (void *) INITRD_START, INITRD_SIZE);
 368         INITRD_START = min_initrd_addr;
 369 #endif
 370 }
 371
 372 /* Set up boot command line */
 373 static void __init append_to_cmdline(size_t (*ipl_data)(char *, size_t))
 374 {
 375         char *parm, *delim;
 376         size_t rc, len;
 377
 378         len = strlen(boot_command_line);
 379
 380         delim = boot_command_line + len;        /* '\0' character position */
 381         parm  = boot_command_line + len + 1;    /* append right after '\0' */
 382
 383         rc = ipl_data(parm, COMMAND_LINE_SIZE - len - 1);
 384         if (rc) {
 385                 if (*parm == '=')
 386                         memmove(boot_command_line, parm + 1, rc);
 387                 else
 388                         *delim = ' ';           /* replace '\0' with space */
 389         }
 390 }
 391
 392 static inline int has_ebcdic_char(const char *str)
 393 {
 394         int i;
 395
 396         for (i = 0; str[i]; i++)
 397                 if (str[i] & 0x80)
 398                         return 1;
 399         return 0;
 400 }
 401
 402 static void __init setup_boot_command_line(void)
 403 {
 404         COMMAND_LINE[ARCH_COMMAND_LINE_SIZE - 1] = 0;
 405         /* convert arch command line to ascii if necessary */
 406         if (has_ebcdic_char(COMMAND_LINE))
 407                 EBCASC(COMMAND_LINE, ARCH_COMMAND_LINE_SIZE);
 408         /* copy arch command line */
 409         strlcpy(boot_command_line, strstrip(COMMAND_LINE),
 410                 ARCH_COMMAND_LINE_SIZE);
 411
 412         /* append IPL PARM data to the boot command line */
 413         if (MACHINE_IS_VM)
 414                 append_to_cmdline(append_ipl_vmparm);
 415
 416         append_to_cmdline(append_ipl_scpdata);
 417 }
 418
 419 /*
 420  * Save ipl parameters, clear bss memory, initialize storage keys
 421  * and create a kernel NSS at startup if the SAVESYS= parm is defined
 422  */
 423 void __init startup_init(void)
 424 {
 425         reset_tod_clock();
 426         ipl_save_parameters();
 427         rescue_initrd();
 428         clear_bss_section();
 429         init_kernel_storage_key();
 430         lockdep_init();
 431         lockdep_off();
 432         setup_lowcore_early();
 433         setup_facility_list();
 434         detect_machine_type();
 435         ipl_update_parameters();
 436         setup_boot_command_line();
 437         create_kernel_nss();
 438         detect_diag9c();
 439         detect_diag44();
 440         detect_machine_facilities();
 441         setup_topology();
 442         sclp_early_detect();
 443         lockdep_on();
 444 }