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 } 212 213 static __init void early_pgm_check_handler(void) 214 { 215 unsigned long addr; 216 const struct exception_table_entry *fixup; 217 218 addr = S390_lowcore.program_old_psw.addr; 219 fixup = search_exception_tables(addr & PSW_ADDR_INSN); 220 if (!fixup) 221 disabled_wait(0); 222 S390_lowcore.program_old_psw.addr = fixup->fixup | PSW_ADDR_AMODE; 223 } 224 225 static noinline __init void setup_lowcore_early(void) 226 { 227 psw_t psw; 228 229 psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY; 230 psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_ext_handler; 231 S390_lowcore.external_new_psw = psw; 232 psw.addr = PSW_ADDR_AMODE | (unsigned long) s390_base_pgm_handler; 233 S390_lowcore.program_new_psw = psw; 234 s390_base_pgm_handler_fn = early_pgm_check_handler; 235 } 236 237 static noinline __init void setup_hpage(void) 238 { 239 #ifndef CONFIG_DEBUG_PAGEALLOC 240 unsigned int facilities; 241 242 facilities = stfl(); 243 if (!(facilities & (1UL << 23)) || !(facilities & (1UL << 29))) 244 return; 245 machine_flags |= MACHINE_FLAG_HPAGE; 246 __ctl_set_bit(0, 23); 247 #endif 248 } 249 250 static __init void detect_mvpg(void) 251 { 252 #ifndef CONFIG_64BIT 253 int rc; 254 255 asm volatile( 256 " la 0,0\n" 257 " mvpg %2,%2\n" 258 "0: la %0,0\n" 259 "1:\n" 260 EX_TABLE(0b,1b) 261 : "=d" (rc) : "0" (-EOPNOTSUPP), "a" (0) : "memory", "cc", "0"); 262 if (!rc) 263 machine_flags |= MACHINE_FLAG_MVPG; 264 #endif 265 } 266 267 static __init void detect_ieee(void) 268 { 269 #ifndef CONFIG_64BIT 270 int rc, tmp; 271 272 asm volatile( 273 " efpc %1,0\n" 274 "0: la %0,0\n" 275 "1:\n" 276 EX_TABLE(0b,1b) 277 : "=d" (rc), "=d" (tmp): "0" (-EOPNOTSUPP) : "cc"); 278 if (!rc) 279 machine_flags |= MACHINE_FLAG_IEEE; 280 #endif 281 } 282 283 static __init void detect_csp(void) 284 { 285 #ifndef CONFIG_64BIT 286 int rc; 287 288 asm volatile( 289 " la 0,0\n" 290 " la 1,0\n" 291 " la 2,4\n" 292 " csp 0,2\n" 293 "0: la %0,0\n" 294 "1:\n" 295 EX_TABLE(0b,1b) 296 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc", "0", "1", "2"); 297 if (!rc) 298 machine_flags |= MACHINE_FLAG_CSP; 299 #endif 300 } 301 302 static __init void detect_diag9c(void) 303 { 304 unsigned int cpu_address; 305 int rc; 306 307 cpu_address = stap(); 308 asm volatile( 309 " diag %2,0,0x9c\n" 310 "0: la %0,0\n" 311 "1:\n" 312 EX_TABLE(0b,1b) 313 : "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc"); 314 if (!rc) 315 machine_flags |= MACHINE_FLAG_DIAG9C; 316 } 317 318 static __init void detect_diag44(void) 319 { 320 #ifdef CONFIG_64BIT 321 int rc; 322 323 asm volatile( 324 " diag 0,0,0x44\n" 325 "0: la %0,0\n" 326 "1:\n" 327 EX_TABLE(0b,1b) 328 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc"); 329 if (!rc) 330 machine_flags |= MACHINE_FLAG_DIAG44; 331 #endif 332 } 333 334 static __init void detect_machine_facilities(void) 335 { 336 #ifdef CONFIG_64BIT 337 unsigned int facilities; 338 339 facilities = stfl(); 340 if (facilities & (1 << 28)) 341 machine_flags |= MACHINE_FLAG_IDTE; 342 if (facilities & (1 << 23)) 343 machine_flags |= MACHINE_FLAG_PFMF; 344 if (facilities & (1 << 4)) 345 machine_flags |= MACHINE_FLAG_MVCOS; 346 #endif 347 } 348 349 static __init void rescue_initrd(void) 350 { 351 #ifdef CONFIG_BLK_DEV_INITRD 352 /* 353 * Move the initrd right behind the bss section in case it starts 354 * within the bss section. So we don't overwrite it when the bss 355 * section gets cleared. 356 */ 357 if (!INITRD_START || !INITRD_SIZE) 358 return; 359 if (INITRD_START >= (unsigned long) __bss_stop) 360 return; 361 memmove(__bss_stop, (void *) INITRD_START, INITRD_SIZE); 362 INITRD_START = (unsigned long) __bss_stop; 363 #endif 364 } 365 366 /* Set up boot command line */ 367 static void __init setup_boot_command_line(void) 368 { 369 char *parm = NULL; 370 371 /* copy arch command line */ 372 strlcpy(boot_command_line, COMMAND_LINE, ARCH_COMMAND_LINE_SIZE); 373 374 /* append IPL PARM data to the boot command line */ 375 if (MACHINE_IS_VM) { 376 parm = boot_command_line + strlen(boot_command_line); 377 *parm++ = ' '; 378 get_ipl_vmparm(parm); 379 if (parm[0] == '=') 380 memmove(boot_command_line, parm + 1, strlen(parm)); 381 } 382 } 383 384 385 /* 386 * Save ipl parameters, clear bss memory, initialize storage keys 387 * and create a kernel NSS at startup if the SAVESYS= parm is defined 388 */ 389 void __init startup_init(void) 390 { 391 reset_tod_clock(); 392 ipl_save_parameters(); 393 rescue_initrd(); 394 clear_bss_section(); 395 init_kernel_storage_key(); 396 lockdep_init(); 397 lockdep_off(); 398 sort_main_extable(); 399 setup_lowcore_early(); 400 detect_machine_type(); 401 ipl_update_parameters(); 402 setup_boot_command_line(); 403 create_kernel_nss(); 404 detect_mvpg(); 405 detect_ieee(); 406 detect_csp(); 407 detect_diag9c(); 408 detect_diag44(); 409 detect_machine_facilities(); 410 setup_hpage(); 411 sclp_facilities_detect(); 412 detect_memory_layout(memory_chunk); 413 S390_lowcore.machine_flags = machine_flags; 414 #ifdef CONFIG_DYNAMIC_FTRACE 415 S390_lowcore.ftrace_func = (unsigned long)ftrace_caller; 416 #endif 417 lockdep_on(); 418 } 419