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 } 59 60 #ifdef CONFIG_SHARED_KERNEL 61 int __init savesys_ipl_nss(char *cmd, const int cmdlen); 62 63 asm( 64 " .section .init.text,\"ax\",@progbits\n" 65 " .align 4\n" 66 " .type savesys_ipl_nss, @function\n" 67 "savesys_ipl_nss:\n" 68 #ifdef CONFIG_64BIT 69 " stmg 6,15,48(15)\n" 70 " lgr 14,3\n" 71 " sam31\n" 72 " diag 2,14,0x8\n" 73 " sam64\n" 74 " lgr 2,14\n" 75 " lmg 6,15,48(15)\n" 76 #else 77 " stm 6,15,24(15)\n" 78 " lr 14,3\n" 79 " diag 2,14,0x8\n" 80 " lr 2,14\n" 81 " lm 6,15,24(15)\n" 82 #endif 83 " br 14\n" 84 " .size savesys_ipl_nss, .-savesys_ipl_nss\n"); 85 86 static __initdata char upper_command_line[COMMAND_LINE_SIZE]; 87 88 static noinline __init void create_kernel_nss(void) 89 { 90 unsigned int i, stext_pfn, eshared_pfn, end_pfn, min_size; 91 #ifdef CONFIG_BLK_DEV_INITRD 92 unsigned int sinitrd_pfn, einitrd_pfn; 93 #endif 94 int response; 95 size_t len; 96 char *savesys_ptr; 97 char defsys_cmd[DEFSYS_CMD_SIZE]; 98 char savesys_cmd[SAVESYS_CMD_SIZE]; 99 100 /* Do nothing if we are not running under VM */ 101 if (!MACHINE_IS_VM) 102 return; 103 104 /* Convert COMMAND_LINE to upper case */ 105 for (i = 0; i < strlen(boot_command_line); i++) 106 upper_command_line[i] = toupper(boot_command_line[i]); 107 108 savesys_ptr = strstr(upper_command_line, "SAVESYS="); 109 110 if (!savesys_ptr) 111 return; 112 113 savesys_ptr += 8; /* Point to the beginning of the NSS name */ 114 for (i = 0; i < NSS_NAME_SIZE; i++) { 115 if (savesys_ptr[i] == ' ' || savesys_ptr[i] == '\0') 116 break; 117 kernel_nss_name[i] = savesys_ptr[i]; 118 } 119 120 stext_pfn = PFN_DOWN(__pa(&_stext)); 121 eshared_pfn = PFN_DOWN(__pa(&_eshared)); 122 end_pfn = PFN_UP(__pa(&_end)); 123 min_size = end_pfn << 2; 124 125 sprintf(defsys_cmd, "DEFSYS %s 00000-%.5X EW %.5X-%.5X SR %.5X-%.5X", 126 kernel_nss_name, stext_pfn - 1, stext_pfn, eshared_pfn - 1, 127 eshared_pfn, end_pfn); 128 129 #ifdef CONFIG_BLK_DEV_INITRD 130 if (INITRD_START && INITRD_SIZE) { 131 sinitrd_pfn = PFN_DOWN(__pa(INITRD_START)); 132 einitrd_pfn = PFN_UP(__pa(INITRD_START + INITRD_SIZE)); 133 min_size = einitrd_pfn << 2; 134 sprintf(defsys_cmd, "%s EW %.5X-%.5X", defsys_cmd, 135 sinitrd_pfn, einitrd_pfn); 136 } 137 #endif 138 139 sprintf(defsys_cmd, "%s EW MINSIZE=%.7iK PARMREGS=0-13", 140 defsys_cmd, min_size); 141 sprintf(savesys_cmd, "SAVESYS %s \n IPL %s", 142 kernel_nss_name, kernel_nss_name); 143 144 __cpcmd(defsys_cmd, NULL, 0, &response); 145 146 if (response != 0) { 147 pr_err("Defining the Linux kernel NSS failed with rc=%d\n", 148 response); 149 kernel_nss_name[0] = '\0'; 150 return; 151 } 152 153 len = strlen(savesys_cmd); 154 ASCEBC(savesys_cmd, len); 155 response = savesys_ipl_nss(savesys_cmd, len); 156 157 /* On success: response is equal to the command size, 158 * max SAVESYS_CMD_SIZE 159 * On error: response contains the numeric portion of cp error message. 160 * for SAVESYS it will be >= 263 161 * for missing privilege class, it will be 1 162 */ 163 if (response > SAVESYS_CMD_SIZE || response == 1) { 164 pr_err("Saving the Linux kernel NSS failed with rc=%d\n", 165 response); 166 kernel_nss_name[0] = '\0'; 167 return; 168 } 169 170 /* re-setup boot command line with new ipl vm parms */ 171 ipl_update_parameters(); 172 setup_boot_command_line(); 173 174 ipl_flags = IPL_NSS_VALID; 175 } 176 177 #else /* CONFIG_SHARED_KERNEL */ 178 179 static inline void create_kernel_nss(void) { } 180 181 #endif /* CONFIG_SHARED_KERNEL */ 182 183 /* 184 * Clear bss memory 185 */ 186 static noinline __init void clear_bss_section(void) 187 { 188 memset(__bss_start, 0, __bss_stop - __bss_start); 189 } 190 191 /* 192 * Initialize storage key for kernel pages 193 */ 194 static noinline __init void init_kernel_storage_key(void) 195 { 196 unsigned long end_pfn, init_pfn; 197 198 end_pfn = PFN_UP(__pa(&_end)); 199 200 for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++) 201 page_set_storage_key(init_pfn << PAGE_SHIFT, PAGE_DEFAULT_KEY); 202 } 203 204 static __initdata struct sysinfo_3_2_2 vmms __aligned(PAGE_SIZE); 205 206 static noinline __init void detect_machine_type(void) 207 { 208 /* No VM information? Looks like LPAR */ 209 if (stsi(&vmms, 3, 2, 2) == -ENOSYS) 210 return; 211 if (!vmms.count) 212 return; 213 214 /* Running under KVM? If not we assume z/VM */ 215 if (!memcmp(vmms.vm[0].cpi, "\xd2\xe5\xd4", 3)) 216 S390_lowcore.machine_flags |= MACHINE_FLAG_KVM; 217 else 218 S390_lowcore.machine_flags |= MACHINE_FLAG_VM; 219 } 220 221 static __init void early_pgm_check_handler(void) 222 { 223 unsigned long addr; 224 const struct exception_table_entry *fixup; 225 226 addr = S390_lowcore.program_old_psw.addr; 227 fixup = search_exception_tables(addr & PSW_ADDR_INSN); 228 if (!fixup) 229 disabled_wait(0); 230 S390_lowcore.program_old_psw.addr = fixup->fixup | PSW_ADDR_AMODE; 231 } 232 233 static noinline __init void setup_lowcore_early(void) 234 { 235 psw_t psw; 236 237 psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY; 238 psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_ext_handler; 239 S390_lowcore.external_new_psw = psw; 240 psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_pgm_handler; 241 S390_lowcore.program_new_psw = psw; 242 s390_base_pgm_handler_fn = early_pgm_check_handler; 243 } 244 245 static noinline __init void setup_hpage(void) 246 { 247 #ifndef CONFIG_DEBUG_PAGEALLOC 248 unsigned int facilities; 249 250 facilities = stfl(); 251 if (!(facilities & (1UL << 23)) || !(facilities & (1UL << 29))) 252 return; 253 S390_lowcore.machine_flags |= MACHINE_FLAG_HPAGE; 254 __ctl_set_bit(0, 23); 255 #endif 256 } 257 258 static __init void detect_mvpg(void) 259 { 260 #ifndef CONFIG_64BIT 261 int rc; 262 263 asm volatile( 264 " la 0,0\n" 265 " mvpg %2,%2\n" 266 "0: la %0,0\n" 267 "1:\n" 268 EX_TABLE(0b,1b) 269 : "=d" (rc) : "0" (-EOPNOTSUPP), "a" (0) : "memory", "cc", "0"); 270 if (!rc) 271 S390_lowcore.machine_flags |= MACHINE_FLAG_MVPG; 272 #endif 273 } 274 275 static __init void detect_ieee(void) 276 { 277 #ifndef CONFIG_64BIT 278 int rc, tmp; 279 280 asm volatile( 281 " efpc %1,0\n" 282 "0: la %0,0\n" 283 "1:\n" 284 EX_TABLE(0b,1b) 285 : "=d" (rc), "=d" (tmp): "0" (-EOPNOTSUPP) : "cc"); 286 if (!rc) 287 S390_lowcore.machine_flags |= MACHINE_FLAG_IEEE; 288 #endif 289 } 290 291 static __init void detect_csp(void) 292 { 293 #ifndef CONFIG_64BIT 294 int rc; 295 296 asm volatile( 297 " la 0,0\n" 298 " la 1,0\n" 299 " la 2,4\n" 300 " csp 0,2\n" 301 "0: la %0,0\n" 302 "1:\n" 303 EX_TABLE(0b,1b) 304 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc", "0", "1", "2"); 305 if (!rc) 306 S390_lowcore.machine_flags |= MACHINE_FLAG_CSP; 307 #endif 308 } 309 310 static __init void detect_diag9c(void) 311 { 312 unsigned int cpu_address; 313 int rc; 314 315 cpu_address = stap(); 316 asm volatile( 317 " diag %2,0,0x9c\n" 318 "0: la %0,0\n" 319 "1:\n" 320 EX_TABLE(0b,1b) 321 : "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc"); 322 if (!rc) 323 S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG9C; 324 } 325 326 static __init void detect_diag44(void) 327 { 328 #ifdef CONFIG_64BIT 329 int rc; 330 331 asm volatile( 332 " diag 0,0,0x44\n" 333 "0: la %0,0\n" 334 "1:\n" 335 EX_TABLE(0b,1b) 336 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc"); 337 if (!rc) 338 S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG44; 339 #endif 340 } 341 342 static __init void detect_machine_facilities(void) 343 { 344 #ifdef CONFIG_64BIT 345 unsigned int facilities; 346 347 facilities = stfl(); 348 if (facilities & (1 << 28)) 349 S390_lowcore.machine_flags |= MACHINE_FLAG_IDTE; 350 if (facilities & (1 << 23)) 351 S390_lowcore.machine_flags |= MACHINE_FLAG_PFMF; 352 if (facilities & (1 << 4)) 353 S390_lowcore.machine_flags |= MACHINE_FLAG_MVCOS; 354 #endif 355 } 356 357 static __init void rescue_initrd(void) 358 { 359 #ifdef CONFIG_BLK_DEV_INITRD 360 /* 361 * Move the initrd right behind the bss section in case it starts 362 * within the bss section. So we don't overwrite it when the bss 363 * section gets cleared. 364 */ 365 if (!INITRD_START || !INITRD_SIZE) 366 return; 367 if (INITRD_START >= (unsigned long) __bss_stop) 368 return; 369 memmove(__bss_stop, (void *) INITRD_START, INITRD_SIZE); 370 INITRD_START = (unsigned long) __bss_stop; 371 #endif 372 } 373 374 /* Set up boot command line */ 375 static void __init append_to_cmdline(size_t (*ipl_data)(char *, size_t)) 376 { 377 char *parm, *delim; 378 size_t rc, len; 379 380 len = strlen(boot_command_line); 381 382 delim = boot_command_line + len; /* '\0' character position */ 383 parm = boot_command_line + len + 1; /* append right after '\0' */ 384 385 rc = ipl_data(parm, COMMAND_LINE_SIZE - len - 1); 386 if (rc) { 387 if (*parm == '=') 388 memmove(boot_command_line, parm + 1, rc); 389 else 390 *delim = ' '; /* replace '\0' with space */ 391 } 392 } 393 394 static void __init setup_boot_command_line(void) 395 { 396 /* copy arch command line */ 397 strlcpy(boot_command_line, COMMAND_LINE, ARCH_COMMAND_LINE_SIZE); 398 399 /* append IPL PARM data to the boot command line */ 400 if (MACHINE_IS_VM) 401 append_to_cmdline(append_ipl_vmparm); 402 403 append_to_cmdline(append_ipl_scpdata); 404 } 405 406 407 /* 408 * Save ipl parameters, clear bss memory, initialize storage keys 409 * and create a kernel NSS at startup if the SAVESYS= parm is defined 410 */ 411 void __init startup_init(void) 412 { 413 reset_tod_clock(); 414 ipl_save_parameters(); 415 rescue_initrd(); 416 clear_bss_section(); 417 init_kernel_storage_key(); 418 lockdep_init(); 419 lockdep_off(); 420 sort_main_extable(); 421 setup_lowcore_early(); 422 detect_machine_type(); 423 ipl_update_parameters(); 424 setup_boot_command_line(); 425 create_kernel_nss(); 426 detect_mvpg(); 427 detect_ieee(); 428 detect_csp(); 429 detect_diag9c(); 430 detect_diag44(); 431 detect_machine_facilities(); 432 setup_hpage(); 433 sclp_facilities_detect(); 434 detect_memory_layout(memory_chunk); 435 #ifdef CONFIG_DYNAMIC_FTRACE 436 S390_lowcore.ftrace_func = (unsigned long)ftrace_caller; 437 #endif 438 lockdep_on(); 439 } 440