arch/s390/kernel/early.c

   1 /*
   2  *  arch/s390/kernel/early.c
   3  *
   4  *    Copyright IBM Corp. 2007
   5  *    Author(s): Hongjie Yang <hongjie@us.ibm.com>,
   6  *               Heiko Carstens <heiko.carstens@de.ibm.com>
   7  */
   8
   9 #include <linux/init.h>
  10 #include <linux/errno.h>
  11 #include <linux/string.h>
  12 #include <linux/ctype.h>
  13 #include <linux/lockdep.h>
  14 #include <linux/module.h>
  15 #include <linux/pfn.h>
  16 #include <linux/uaccess.h>
  17 #include <asm/ebcdic.h>
  18 #include <asm/ipl.h>
  19 #include <asm/lowcore.h>
  20 #include <asm/processor.h>
  21 #include <asm/sections.h>
  22 #include <asm/setup.h>
  23 #include <asm/cpcmd.h>
  24 #include <asm/sclp.h>
  25 #include "entry.h"
  26
  27 /*
  28  * Create a Kernel NSS if the SAVESYS= parameter is defined
  29  */
  30 #define DEFSYS_CMD_SIZE         128
  31 #define SAVESYS_CMD_SIZE        32
  32
  33 char kernel_nss_name[NSS_NAME_SIZE + 1];
  34
  35 static void __init setup_boot_command_line(void);
  36
  37
  38 #ifdef CONFIG_SHARED_KERNEL
  39 int __init savesys_ipl_nss(char *cmd, const int cmdlen);
  40
  41 asm(
  42         "       .section .init.text,\"ax\",@progbits\n"
  43         "       .align  4\n"
  44         "       .type   savesys_ipl_nss, @function\n"
  45         "savesys_ipl_nss:\n"
  46 #ifdef CONFIG_64BIT
  47         "       stmg    6,15,48(15)\n"
  48         "       lgr     14,3\n"
  49         "       sam31\n"
  50         "       diag    2,14,0x8\n"
  51         "       sam64\n"
  52         "       lgr     2,14\n"
  53         "       lmg     6,15,48(15)\n"
  54 #else
  55         "       stm     6,15,24(15)\n"
  56         "       lr      14,3\n"
  57         "       diag    2,14,0x8\n"
  58         "       lr      2,14\n"
  59         "       lm      6,15,24(15)\n"
  60 #endif
  61         "       br      14\n"
  62         "       .size   savesys_ipl_nss, .-savesys_ipl_nss\n");
  63
  64 static noinline __init void create_kernel_nss(void)
  65 {
  66         unsigned int i, stext_pfn, eshared_pfn, end_pfn, min_size;
  67 #ifdef CONFIG_BLK_DEV_INITRD
  68         unsigned int sinitrd_pfn, einitrd_pfn;
  69 #endif
  70         int response;
  71         size_t len;
  72         char *savesys_ptr;
  73         char upper_command_line[COMMAND_LINE_SIZE];
  74         char defsys_cmd[DEFSYS_CMD_SIZE];
  75         char savesys_cmd[SAVESYS_CMD_SIZE];
  76
  77         /* Do nothing if we are not running under VM */
  78         if (!MACHINE_IS_VM)
  79                 return;
  80
  81         /* Convert COMMAND_LINE to upper case */
  82         for (i = 0; i < strlen(boot_command_line); i++)
  83                 upper_command_line[i] = toupper(boot_command_line[i]);
  84
  85         savesys_ptr = strstr(upper_command_line, "SAVESYS=");
  86
  87         if (!savesys_ptr)
  88                 return;
  89
  90         savesys_ptr += 8;    /* Point to the beginning of the NSS name */
  91         for (i = 0; i < NSS_NAME_SIZE; i++) {
  92                 if (savesys_ptr[i] == ' ' || savesys_ptr[i] == '\0')
  93                         break;
  94                 kernel_nss_name[i] = savesys_ptr[i];
  95         }
  96
  97         stext_pfn = PFN_DOWN(__pa(&_stext));
  98         eshared_pfn = PFN_DOWN(__pa(&_eshared));
  99         end_pfn = PFN_UP(__pa(&_end));
 100         min_size = end_pfn << 2;
 101
 102         sprintf(defsys_cmd, "DEFSYS %s 00000-%.5X EW %.5X-%.5X SR %.5X-%.5X",
 103                 kernel_nss_name, stext_pfn - 1, stext_pfn, eshared_pfn - 1,
 104                 eshared_pfn, end_pfn);
 105
 106 #ifdef CONFIG_BLK_DEV_INITRD
 107         if (INITRD_START && INITRD_SIZE) {
 108                 sinitrd_pfn = PFN_DOWN(__pa(INITRD_START));
 109                 einitrd_pfn = PFN_UP(__pa(INITRD_START + INITRD_SIZE));
 110                 min_size = einitrd_pfn << 2;
 111                 sprintf(defsys_cmd, "%s EW %.5X-%.5X", defsys_cmd,
 112                 sinitrd_pfn, einitrd_pfn);
 113         }
 114 #endif
 115
 116         sprintf(defsys_cmd, "%s EW MINSIZE=%.7iK PARMREGS=0-13",
 117                 defsys_cmd, min_size);
 118         sprintf(savesys_cmd, "SAVESYS %s \n IPL %s",
 119                 kernel_nss_name, kernel_nss_name);
 120
 121         __cpcmd(defsys_cmd, NULL, 0, &response);
 122
 123         if (response != 0) {
 124                 kernel_nss_name[0] = '\0';
 125                 return;
 126         }
 127
 128         len = strlen(savesys_cmd);
 129         ASCEBC(savesys_cmd, len);
 130         response = savesys_ipl_nss(savesys_cmd, len);
 131
 132         /* On success: response is equal to the command size,
 133          *             max SAVESYS_CMD_SIZE
 134          * On error: response contains the numeric portion of cp error message.
 135          *           for SAVESYS it will be >= 263
 136          */
 137         if (response > SAVESYS_CMD_SIZE) {
 138                 kernel_nss_name[0] = '\0';
 139                 return;
 140         }
 141
 142         /* re-setup boot command line with new ipl vm parms */
 143         ipl_update_parameters();
 144         setup_boot_command_line();
 145
 146         ipl_flags = IPL_NSS_VALID;
 147 }
 148
 149 #else /* CONFIG_SHARED_KERNEL */
 150
 151 static inline void create_kernel_nss(void) { }
 152
 153 #endif /* CONFIG_SHARED_KERNEL */
 154
 155 /*
 156  * Clear bss memory
 157  */
 158 static noinline __init void clear_bss_section(void)
 159 {
 160         memset(__bss_start, 0, __bss_stop - __bss_start);
 161 }
 162
 163 /*
 164  * Initialize storage key for kernel pages
 165  */
 166 static noinline __init void init_kernel_storage_key(void)
 167 {
 168         unsigned long end_pfn, init_pfn;
 169
 170         end_pfn = PFN_UP(__pa(&_end));
 171
 172         for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++)
 173                 page_set_storage_key(init_pfn << PAGE_SHIFT, PAGE_DEFAULT_KEY);
 174 }
 175
 176 static noinline __init void detect_machine_type(void)
 177 {
 178         struct cpuinfo_S390 *cpuinfo = &S390_lowcore.cpu_data;
 179
 180         get_cpu_id(&S390_lowcore.cpu_data.cpu_id);
 181
 182         /* Running under z/VM ? */
 183         if (cpuinfo->cpu_id.version == 0xff)
 184                 machine_flags |= MACHINE_FLAG_VM;
 185
 186         /* Running under KVM ? */
 187         if (cpuinfo->cpu_id.version == 0xfe)
 188                 machine_flags |= MACHINE_FLAG_KVM;
 189 }
 190
 191 static __init void early_pgm_check_handler(void)
 192 {
 193         unsigned long addr;
 194         const struct exception_table_entry *fixup;
 195
 196         addr = S390_lowcore.program_old_psw.addr;
 197         fixup = search_exception_tables(addr & PSW_ADDR_INSN);
 198         if (!fixup)
 199                 disabled_wait(0);
 200         S390_lowcore.program_old_psw.addr = fixup->fixup | PSW_ADDR_AMODE;
 201 }
 202
 203 static noinline __init void setup_lowcore_early(void)
 204 {
 205         psw_t psw;
 206
 207         psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
 208         psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_ext_handler;
 209         S390_lowcore.external_new_psw = psw;
 210         psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_pgm_handler;
 211         S390_lowcore.program_new_psw = psw;
 212         s390_base_pgm_handler_fn = early_pgm_check_handler;
 213 }
 214
 215 static noinline __init void setup_hpage(void)
 216 {
 217 #ifndef CONFIG_DEBUG_PAGEALLOC
 218         unsigned int facilities;
 219
 220         facilities = stfl();
 221         if (!(facilities & (1UL << 23)) || !(facilities & (1UL << 29)))
 222                 return;
 223         machine_flags |= MACHINE_FLAG_HPAGE;
 224         __ctl_set_bit(0, 23);
 225 #endif
 226 }
 227
 228 static __init void detect_mvpg(void)
 229 {
 230 #ifndef CONFIG_64BIT
 231         int rc;
 232
 233         asm volatile(
 234                 "       la      0,0\n"
 235                 "       mvpg    %2,%2\n"
 236                 "0:     la      %0,0\n"
 237                 "1:\n"
 238                 EX_TABLE(0b,1b)
 239                 : "=d" (rc) : "0" (-EOPNOTSUPP), "a" (0) : "memory", "cc", "0");
 240         if (!rc)
 241                 machine_flags |= MACHINE_FLAG_MVPG;
 242 #endif
 243 }
 244
 245 static __init void detect_ieee(void)
 246 {
 247 #ifndef CONFIG_64BIT
 248         int rc, tmp;
 249
 250         asm volatile(
 251                 "       efpc    %1,0\n"
 252                 "0:     la      %0,0\n"
 253                 "1:\n"
 254                 EX_TABLE(0b,1b)
 255                 : "=d" (rc), "=d" (tmp): "0" (-EOPNOTSUPP) : "cc");
 256         if (!rc)
 257                 machine_flags |= MACHINE_FLAG_IEEE;
 258 #endif
 259 }
 260
 261 static __init void detect_csp(void)
 262 {
 263 #ifndef CONFIG_64BIT
 264         int rc;
 265
 266         asm volatile(
 267                 "       la      0,0\n"
 268                 "       la      1,0\n"
 269                 "       la      2,4\n"
 270                 "       csp     0,2\n"
 271                 "0:     la      %0,0\n"
 272                 "1:\n"
 273                 EX_TABLE(0b,1b)
 274                 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc", "0", "1", "2");
 275         if (!rc)
 276                 machine_flags |= MACHINE_FLAG_CSP;
 277 #endif
 278 }
 279
 280 static __init void detect_diag9c(void)
 281 {
 282         unsigned int cpu_address;
 283         int rc;
 284
 285         cpu_address = stap();
 286         asm volatile(
 287                 "       diag    %2,0,0x9c\n"
 288                 "0:     la      %0,0\n"
 289                 "1:\n"
 290                 EX_TABLE(0b,1b)
 291                 : "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc");
 292         if (!rc)
 293                 machine_flags |= MACHINE_FLAG_DIAG9C;
 294 }
 295
 296 static __init void detect_diag44(void)
 297 {
 298 #ifdef CONFIG_64BIT
 299         int rc;
 300
 301         asm volatile(
 302                 "       diag    0,0,0x44\n"
 303                 "0:     la      %0,0\n"
 304                 "1:\n"
 305                 EX_TABLE(0b,1b)
 306                 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc");
 307         if (!rc)
 308                 machine_flags |= MACHINE_FLAG_DIAG44;
 309 #endif
 310 }
 311
 312 static __init void detect_machine_facilities(void)
 313 {
 314 #ifdef CONFIG_64BIT
 315         unsigned int facilities;
 316
 317         facilities = stfl();
 318         if (facilities & (1 << 28))
 319                 machine_flags |= MACHINE_FLAG_IDTE;
 320         if (facilities & (1 << 23))
 321                 machine_flags |= MACHINE_FLAG_PFMF;
 322         if (facilities & (1 << 4))
 323                 machine_flags |= MACHINE_FLAG_MVCOS;
 324 #endif
 325 }
 326
 327 static __init void rescue_initrd(void)
 328 {
 329 #ifdef CONFIG_BLK_DEV_INITRD
 330         /*
 331          * Move the initrd right behind the bss section in case it starts
 332          * within the bss section. So we don't overwrite it when the bss
 333          * section gets cleared.
 334          */
 335         if (!INITRD_START || !INITRD_SIZE)
 336                 return;
 337         if (INITRD_START >= (unsigned long) __bss_stop)
 338                 return;
 339         memmove(__bss_stop, (void *) INITRD_START, INITRD_SIZE);
 340         INITRD_START = (unsigned long) __bss_stop;
 341 #endif
 342 }
 343
 344 /* Set up boot command line */
 345 static void __init setup_boot_command_line(void)
 346 {
 347         char *parm = NULL;
 348
 349         /* copy arch command line */
 350         strlcpy(boot_command_line, COMMAND_LINE, ARCH_COMMAND_LINE_SIZE);
 351         boot_command_line[ARCH_COMMAND_LINE_SIZE - 1] = 0;
 352
 353         /* append IPL PARM data to the boot command line */
 354         if (MACHINE_IS_VM) {
 355                 parm = boot_command_line + strlen(boot_command_line);
 356                 *parm++ = ' ';
 357                 get_ipl_vmparm(parm);
 358                 if (parm[0] == '=')
 359                         memmove(boot_command_line, parm + 1, strlen(parm));
 360         }
 361 }
 362
 363
 364 /*
 365  * Save ipl parameters, clear bss memory, initialize storage keys
 366  * and create a kernel NSS at startup if the SAVESYS= parm is defined
 367  */
 368 void __init startup_init(void)
 369 {
 370         ipl_save_parameters();
 371         rescue_initrd();
 372         clear_bss_section();
 373         init_kernel_storage_key();
 374         lockdep_init();
 375         lockdep_off();
 376         sort_main_extable();
 377         setup_lowcore_early();
 378         detect_machine_type();
 379         ipl_update_parameters();
 380         setup_boot_command_line();
 381         create_kernel_nss();
 382         detect_mvpg();
 383         detect_ieee();
 384         detect_csp();
 385         detect_diag9c();
 386         detect_diag44();
 387         detect_machine_facilities();
 388         setup_hpage();
 389         sclp_facilities_detect();
 390         detect_memory_layout(memory_chunk);
 391         lockdep_on();
 392 }