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 #include <linux/compiler.h> 10 #include <linux/init.h> 11 #include <linux/errno.h> 12 #include <linux/string.h> 13 #include <linux/ctype.h> 14 #include <linux/ftrace.h> 15 #include <linux/lockdep.h> 16 #include <linux/module.h> 17 #include <linux/pfn.h> 18 #include <linux/uaccess.h> 19 #include <asm/ebcdic.h> 20 #include <asm/ipl.h> 21 #include <asm/lowcore.h> 22 #include <asm/processor.h> 23 #include <asm/sections.h> 24 #include <asm/setup.h> 25 #include <asm/sysinfo.h> 26 #include <asm/cpcmd.h> 27 #include <asm/sclp.h> 28 #include "entry.h" 29 30 /* 31 * Create a Kernel NSS if the SAVESYS= parameter is defined 32 */ 33 #define DEFSYS_CMD_SIZE 128 34 #define SAVESYS_CMD_SIZE 32 35 36 char kernel_nss_name[NSS_NAME_SIZE + 1]; 37 38 static unsigned long machine_flags; 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_clock(&time) == 0) 50 return; 51 /* TOD clock not running. Set the clock to Unix Epoch. */ 52 if (set_clock(TOD_UNIX_EPOCH) != 0 || store_clock(&time) != 0) 53 disabled_wait(0); 54 55 sched_clock_base_cc = TOD_UNIX_EPOCH; 56 } 57 58 #ifdef CONFIG_SHARED_KERNEL 59 int __init savesys_ipl_nss(char *cmd, const int cmdlen); 60 61 asm( 62 " .section .init.text,\"ax\",@progbits\n" 63 " .align 4\n" 64 " .type savesys_ipl_nss, @function\n" 65 "savesys_ipl_nss:\n" 66 #ifdef CONFIG_64BIT 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 #else 75 " stm 6,15,24(15)\n" 76 " lr 14,3\n" 77 " diag 2,14,0x8\n" 78 " lr 2,14\n" 79 " lm 6,15,24(15)\n" 80 #endif 81 " br 14\n" 82 " .size savesys_ipl_nss, .-savesys_ipl_nss\n"); 83 84 static noinline __init void create_kernel_nss(void) 85 { 86 unsigned int i, stext_pfn, eshared_pfn, end_pfn, min_size; 87 #ifdef CONFIG_BLK_DEV_INITRD 88 unsigned int sinitrd_pfn, einitrd_pfn; 89 #endif 90 int response; 91 size_t len; 92 char *savesys_ptr; 93 char upper_command_line[COMMAND_LINE_SIZE]; 94 char defsys_cmd[DEFSYS_CMD_SIZE]; 95 char savesys_cmd[SAVESYS_CMD_SIZE]; 96 97 /* Do nothing if we are not running under VM */ 98 if (!MACHINE_IS_VM) 99 return; 100 101 /* Convert COMMAND_LINE to upper case */ 102 for (i = 0; i < strlen(boot_command_line); i++) 103 upper_command_line[i] = toupper(boot_command_line[i]); 104 105 savesys_ptr = strstr(upper_command_line, "SAVESYS="); 106 107 if (!savesys_ptr) 108 return; 109 110 savesys_ptr += 8; /* Point to the beginning of the NSS name */ 111 for (i = 0; i < NSS_NAME_SIZE; i++) { 112 if (savesys_ptr[i] == ' ' || savesys_ptr[i] == '\0') 113 break; 114 kernel_nss_name[i] = savesys_ptr[i]; 115 } 116 117 stext_pfn = PFN_DOWN(__pa(&_stext)); 118 eshared_pfn = PFN_DOWN(__pa(&_eshared)); 119 end_pfn = PFN_UP(__pa(&_end)); 120 min_size = end_pfn << 2; 121 122 sprintf(defsys_cmd, "DEFSYS %s 00000-%.5X EW %.5X-%.5X SR %.5X-%.5X", 123 kernel_nss_name, stext_pfn - 1, stext_pfn, eshared_pfn - 1, 124 eshared_pfn, end_pfn); 125 126 #ifdef CONFIG_BLK_DEV_INITRD 127 if (INITRD_START && INITRD_SIZE) { 128 sinitrd_pfn = PFN_DOWN(__pa(INITRD_START)); 129 einitrd_pfn = PFN_UP(__pa(INITRD_START + INITRD_SIZE)); 130 min_size = einitrd_pfn << 2; 131 sprintf(defsys_cmd, "%s EW %.5X-%.5X", defsys_cmd, 132 sinitrd_pfn, einitrd_pfn); 133 } 134 #endif 135 136 sprintf(defsys_cmd, "%s EW MINSIZE=%.7iK PARMREGS=0-13", 137 defsys_cmd, min_size); 138 sprintf(savesys_cmd, "SAVESYS %s \n IPL %s", 139 kernel_nss_name, kernel_nss_name); 140 141 __cpcmd(defsys_cmd, NULL, 0, &response); 142 143 if (response != 0) { 144 kernel_nss_name[0] = '\0'; 145 return; 146 } 147 148 len = strlen(savesys_cmd); 149 ASCEBC(savesys_cmd, len); 150 response = savesys_ipl_nss(savesys_cmd, len); 151 152 /* On success: response is equal to the command size, 153 * max SAVESYS_CMD_SIZE 154 * On error: response contains the numeric portion of cp error message. 155 * for SAVESYS it will be >= 263 156 */ 157 if (response > SAVESYS_CMD_SIZE) { 158 kernel_nss_name[0] = '\0'; 159 return; 160 } 161 162 /* re-setup boot command line with new ipl vm parms */ 163 ipl_update_parameters(); 164 setup_boot_command_line(); 165 166 ipl_flags = IPL_NSS_VALID; 167 } 168 169 #else /* CONFIG_SHARED_KERNEL */ 170 171 static inline void create_kernel_nss(void) { } 172 173 #endif /* CONFIG_SHARED_KERNEL */ 174 175 /* 176 * Clear bss memory 177 */ 178 static noinline __init void clear_bss_section(void) 179 { 180 memset(__bss_start, 0, __bss_stop - __bss_start); 181 } 182 183 /* 184 * Initialize storage key for kernel pages 185 */ 186 static noinline __init void init_kernel_storage_key(void) 187 { 188 unsigned long end_pfn, init_pfn; 189 190 end_pfn = PFN_UP(__pa(&_end)); 191 192 for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++) 193 page_set_storage_key(init_pfn << PAGE_SHIFT, PAGE_DEFAULT_KEY); 194 } 195 196 static __initdata struct sysinfo_3_2_2 vmms __aligned(PAGE_SIZE); 197 198 static noinline __init void detect_machine_type(void) 199 { 200 /* No VM information? Looks like LPAR */ 201 if (stsi(&vmms, 3, 2, 2) == -ENOSYS) 202 return; 203 if (!vmms.count) 204 return; 205 206 /* Running under KVM? If not we assume z/VM */ 207 if (!memcmp(vmms.vm[0].cpi, "\xd2\xe5\xd4", 3)) 208 machine_flags |= MACHINE_FLAG_KVM; 209 else 210 machine_flags |= MACHINE_FLAG_VM; 211 212 /* Store machine flags for setting up lowcore early */ 213 S390_lowcore.machine_flags = machine_flags; 214 } 215 216 static __init void early_pgm_check_handler(void) 217 { 218 unsigned long addr; 219 const struct exception_table_entry *fixup; 220 221 addr = S390_lowcore.program_old_psw.addr; 222 fixup = search_exception_tables(addr & PSW_ADDR_INSN); 223 if (!fixup) 224 disabled_wait(0); 225 S390_lowcore.program_old_psw.addr = fixup->fixup | PSW_ADDR_AMODE; 226 } 227 228 static noinline __init void setup_lowcore_early(void) 229 { 230 psw_t psw; 231 232 psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY; 233 psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_ext_handler; 234 S390_lowcore.external_new_psw = psw; 235 psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_pgm_handler; 236 S390_lowcore.program_new_psw = psw; 237 s390_base_pgm_handler_fn = early_pgm_check_handler; 238 } 239 240 static noinline __init void setup_hpage(void) 241 { 242 #ifndef CONFIG_DEBUG_PAGEALLOC 243 unsigned int facilities; 244 245 facilities = stfl(); 246 if (!(facilities & (1UL << 23)) || !(facilities & (1UL << 29))) 247 return; 248 machine_flags |= MACHINE_FLAG_HPAGE; 249 __ctl_set_bit(0, 23); 250 #endif 251 } 252 253 static __init void detect_mvpg(void) 254 { 255 #ifndef CONFIG_64BIT 256 int rc; 257 258 asm volatile( 259 " la 0,0\n" 260 " mvpg %2,%2\n" 261 "0: la %0,0\n" 262 "1:\n" 263 EX_TABLE(0b,1b) 264 : "=d" (rc) : "0" (-EOPNOTSUPP), "a" (0) : "memory", "cc", "0"); 265 if (!rc) 266 machine_flags |= MACHINE_FLAG_MVPG; 267 #endif 268 } 269 270 static __init void detect_ieee(void) 271 { 272 #ifndef CONFIG_64BIT 273 int rc, tmp; 274 275 asm volatile( 276 " efpc %1,0\n" 277 "0: la %0,0\n" 278 "1:\n" 279 EX_TABLE(0b,1b) 280 : "=d" (rc), "=d" (tmp): "0" (-EOPNOTSUPP) : "cc"); 281 if (!rc) 282 machine_flags |= MACHINE_FLAG_IEEE; 283 #endif 284 } 285 286 static __init void detect_csp(void) 287 { 288 #ifndef CONFIG_64BIT 289 int rc; 290 291 asm volatile( 292 " la 0,0\n" 293 " la 1,0\n" 294 " la 2,4\n" 295 " csp 0,2\n" 296 "0: la %0,0\n" 297 "1:\n" 298 EX_TABLE(0b,1b) 299 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc", "0", "1", "2"); 300 if (!rc) 301 machine_flags |= MACHINE_FLAG_CSP; 302 #endif 303 } 304 305 static __init void detect_diag9c(void) 306 { 307 unsigned int cpu_address; 308 int rc; 309 310 cpu_address = stap(); 311 asm volatile( 312 " diag %2,0,0x9c\n" 313 "0: la %0,0\n" 314 "1:\n" 315 EX_TABLE(0b,1b) 316 : "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc"); 317 if (!rc) 318 machine_flags |= MACHINE_FLAG_DIAG9C; 319 } 320 321 static __init void detect_diag44(void) 322 { 323 #ifdef CONFIG_64BIT 324 int rc; 325 326 asm volatile( 327 " diag 0,0,0x44\n" 328 "0: la %0,0\n" 329 "1:\n" 330 EX_TABLE(0b,1b) 331 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc"); 332 if (!rc) 333 machine_flags |= MACHINE_FLAG_DIAG44; 334 #endif 335 } 336 337 static __init void detect_machine_facilities(void) 338 { 339 #ifdef CONFIG_64BIT 340 unsigned int facilities; 341 342 facilities = stfl(); 343 if (facilities & (1 << 28)) 344 machine_flags |= MACHINE_FLAG_IDTE; 345 if (facilities & (1 << 23)) 346 machine_flags |= MACHINE_FLAG_PFMF; 347 if (facilities & (1 << 4)) 348 machine_flags |= MACHINE_FLAG_MVCOS; 349 #endif 350 } 351 352 static __init void rescue_initrd(void) 353 { 354 #ifdef CONFIG_BLK_DEV_INITRD 355 /* 356 * Move the initrd right behind the bss section in case it starts 357 * within the bss section. So we don't overwrite it when the bss 358 * section gets cleared. 359 */ 360 if (!INITRD_START || !INITRD_SIZE) 361 return; 362 if (INITRD_START >= (unsigned long) __bss_stop) 363 return; 364 memmove(__bss_stop, (void *) INITRD_START, INITRD_SIZE); 365 INITRD_START = (unsigned long) __bss_stop; 366 #endif 367 } 368 369 /* Set up boot command line */ 370 static void __init setup_boot_command_line(void) 371 { 372 char *parm = NULL; 373 374 /* copy arch command line */ 375 strlcpy(boot_command_line, COMMAND_LINE, ARCH_COMMAND_LINE_SIZE); 376 377 /* append IPL PARM data to the boot command line */ 378 if (MACHINE_IS_VM) { 379 parm = boot_command_line + strlen(boot_command_line); 380 *parm++ = ' '; 381 get_ipl_vmparm(parm); 382 if (parm[0] == '=') 383 memmove(boot_command_line, parm + 1, strlen(parm)); 384 } 385 } 386 387 388 /* 389 * Save ipl parameters, clear bss memory, initialize storage keys 390 * and create a kernel NSS at startup if the SAVESYS= parm is defined 391 */ 392 void __init startup_init(void) 393 { 394 reset_tod_clock(); 395 ipl_save_parameters(); 396 rescue_initrd(); 397 clear_bss_section(); 398 init_kernel_storage_key(); 399 lockdep_init(); 400 lockdep_off(); 401 sort_main_extable(); 402 setup_lowcore_early(); 403 detect_machine_type(); 404 ipl_update_parameters(); 405 setup_boot_command_line(); 406 create_kernel_nss(); 407 detect_mvpg(); 408 detect_ieee(); 409 detect_csp(); 410 detect_diag9c(); 411 detect_diag44(); 412 detect_machine_facilities(); 413 setup_hpage(); 414 sclp_facilities_detect(); 415 detect_memory_layout(memory_chunk); 416 S390_lowcore.machine_flags = machine_flags; 417 #ifdef CONFIG_DYNAMIC_FTRACE 418 S390_lowcore.ftrace_func = (unsigned long)ftrace_caller; 419 #endif 420 lockdep_on(); 421 } 422