1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright IBM Corp. 2007, 2009 4 * Author(s): Hongjie Yang <hongjie@us.ibm.com>, 5 * Heiko Carstens <heiko.carstens@de.ibm.com> 6 */ 7 8 #define KMSG_COMPONENT "setup" 9 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 10 11 #include <linux/compiler.h> 12 #include <linux/init.h> 13 #include <linux/errno.h> 14 #include <linux/string.h> 15 #include <linux/ctype.h> 16 #include <linux/lockdep.h> 17 #include <linux/extable.h> 18 #include <linux/pfn.h> 19 #include <linux/uaccess.h> 20 #include <linux/kernel.h> 21 #include <asm/diag.h> 22 #include <asm/ebcdic.h> 23 #include <asm/ipl.h> 24 #include <asm/lowcore.h> 25 #include <asm/processor.h> 26 #include <asm/sections.h> 27 #include <asm/setup.h> 28 #include <asm/sysinfo.h> 29 #include <asm/cpcmd.h> 30 #include <asm/sclp.h> 31 #include <asm/facility.h> 32 #include <asm/boot_data.h> 33 #include "entry.h" 34 35 static void __init reset_tod_clock(void) 36 { 37 u64 time; 38 39 if (store_tod_clock(&time) == 0) 40 return; 41 /* TOD clock not running. Set the clock to Unix Epoch. */ 42 if (set_tod_clock(TOD_UNIX_EPOCH) != 0 || store_tod_clock(&time) != 0) 43 disabled_wait(); 44 45 memset(tod_clock_base, 0, 16); 46 *(__u64 *) &tod_clock_base[1] = TOD_UNIX_EPOCH; 47 S390_lowcore.last_update_clock = TOD_UNIX_EPOCH; 48 } 49 50 /* 51 * Initialize storage key for kernel pages 52 */ 53 static noinline __init void init_kernel_storage_key(void) 54 { 55 #if PAGE_DEFAULT_KEY 56 unsigned long end_pfn, init_pfn; 57 58 end_pfn = PFN_UP(__pa(_end)); 59 60 for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++) 61 page_set_storage_key(init_pfn << PAGE_SHIFT, 62 PAGE_DEFAULT_KEY, 0); 63 #endif 64 } 65 66 static __initdata char sysinfo_page[PAGE_SIZE] __aligned(PAGE_SIZE); 67 68 static noinline __init void detect_machine_type(void) 69 { 70 struct sysinfo_3_2_2 *vmms = (struct sysinfo_3_2_2 *)&sysinfo_page; 71 72 /* Check current-configuration-level */ 73 if (stsi(NULL, 0, 0, 0) <= 2) { 74 S390_lowcore.machine_flags |= MACHINE_FLAG_LPAR; 75 return; 76 } 77 /* Get virtual-machine cpu information. */ 78 if (stsi(vmms, 3, 2, 2) || !vmms->count) 79 return; 80 81 /* Detect known hypervisors */ 82 if (!memcmp(vmms->vm[0].cpi, "\xd2\xe5\xd4", 3)) 83 S390_lowcore.machine_flags |= MACHINE_FLAG_KVM; 84 else if (!memcmp(vmms->vm[0].cpi, "\xa9\x61\xe5\xd4", 4)) 85 S390_lowcore.machine_flags |= MACHINE_FLAG_VM; 86 } 87 88 /* Remove leading, trailing and double whitespace. */ 89 static inline void strim_all(char *str) 90 { 91 char *s; 92 93 s = strim(str); 94 if (s != str) 95 memmove(str, s, strlen(s)); 96 while (*str) { 97 if (!isspace(*str++)) 98 continue; 99 if (isspace(*str)) { 100 s = skip_spaces(str); 101 memmove(str, s, strlen(s) + 1); 102 } 103 } 104 } 105 106 static noinline __init void setup_arch_string(void) 107 { 108 struct sysinfo_1_1_1 *mach = (struct sysinfo_1_1_1 *)&sysinfo_page; 109 struct sysinfo_3_2_2 *vm = (struct sysinfo_3_2_2 *)&sysinfo_page; 110 char mstr[80], hvstr[17]; 111 112 if (stsi(mach, 1, 1, 1)) 113 return; 114 EBCASC(mach->manufacturer, sizeof(mach->manufacturer)); 115 EBCASC(mach->type, sizeof(mach->type)); 116 EBCASC(mach->model, sizeof(mach->model)); 117 EBCASC(mach->model_capacity, sizeof(mach->model_capacity)); 118 sprintf(mstr, "%-16.16s %-4.4s %-16.16s %-16.16s", 119 mach->manufacturer, mach->type, 120 mach->model, mach->model_capacity); 121 strim_all(mstr); 122 if (stsi(vm, 3, 2, 2) == 0 && vm->count) { 123 EBCASC(vm->vm[0].cpi, sizeof(vm->vm[0].cpi)); 124 sprintf(hvstr, "%-16.16s", vm->vm[0].cpi); 125 strim_all(hvstr); 126 } else { 127 sprintf(hvstr, "%s", 128 MACHINE_IS_LPAR ? "LPAR" : 129 MACHINE_IS_VM ? "z/VM" : 130 MACHINE_IS_KVM ? "KVM" : "unknown"); 131 } 132 dump_stack_set_arch_desc("%s (%s)", mstr, hvstr); 133 } 134 135 static __init void setup_topology(void) 136 { 137 int max_mnest; 138 139 if (!test_facility(11)) 140 return; 141 S390_lowcore.machine_flags |= MACHINE_FLAG_TOPOLOGY; 142 for (max_mnest = 6; max_mnest > 1; max_mnest--) { 143 if (stsi(&sysinfo_page, 15, 1, max_mnest) == 0) 144 break; 145 } 146 topology_max_mnest = max_mnest; 147 } 148 149 static void early_pgm_check_handler(void) 150 { 151 const struct exception_table_entry *fixup; 152 unsigned long cr0, cr0_new; 153 unsigned long addr; 154 155 addr = S390_lowcore.program_old_psw.addr; 156 fixup = s390_search_extables(addr); 157 if (!fixup) 158 disabled_wait(); 159 /* Disable low address protection before storing into lowcore. */ 160 __ctl_store(cr0, 0, 0); 161 cr0_new = cr0 & ~(1UL << 28); 162 __ctl_load(cr0_new, 0, 0); 163 S390_lowcore.program_old_psw.addr = extable_fixup(fixup); 164 __ctl_load(cr0, 0, 0); 165 } 166 167 static noinline __init void setup_lowcore_early(void) 168 { 169 psw_t psw; 170 171 psw.mask = PSW_MASK_BASE | PSW_DEFAULT_KEY | PSW_MASK_EA | PSW_MASK_BA; 172 psw.addr = (unsigned long) s390_base_ext_handler; 173 S390_lowcore.external_new_psw = psw; 174 psw.addr = (unsigned long) s390_base_pgm_handler; 175 S390_lowcore.program_new_psw = psw; 176 s390_base_pgm_handler_fn = early_pgm_check_handler; 177 S390_lowcore.preempt_count = INIT_PREEMPT_COUNT; 178 } 179 180 static noinline __init void setup_facility_list(void) 181 { 182 memcpy(S390_lowcore.alt_stfle_fac_list, 183 S390_lowcore.stfle_fac_list, 184 sizeof(S390_lowcore.alt_stfle_fac_list)); 185 if (!IS_ENABLED(CONFIG_KERNEL_NOBP)) 186 __clear_facility(82, S390_lowcore.alt_stfle_fac_list); 187 } 188 189 static __init void detect_diag9c(void) 190 { 191 unsigned int cpu_address; 192 int rc; 193 194 cpu_address = stap(); 195 diag_stat_inc(DIAG_STAT_X09C); 196 asm volatile( 197 " diag %2,0,0x9c\n" 198 "0: la %0,0\n" 199 "1:\n" 200 EX_TABLE(0b,1b) 201 : "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc"); 202 if (!rc) 203 S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG9C; 204 } 205 206 static __init void detect_diag44(void) 207 { 208 int rc; 209 210 diag_stat_inc(DIAG_STAT_X044); 211 asm volatile( 212 " diag 0,0,0x44\n" 213 "0: la %0,0\n" 214 "1:\n" 215 EX_TABLE(0b,1b) 216 : "=d" (rc) : "0" (-EOPNOTSUPP) : "cc"); 217 if (!rc) 218 S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG44; 219 } 220 221 static __init void detect_machine_facilities(void) 222 { 223 if (test_facility(8)) { 224 S390_lowcore.machine_flags |= MACHINE_FLAG_EDAT1; 225 __ctl_set_bit(0, 23); 226 } 227 if (test_facility(78)) 228 S390_lowcore.machine_flags |= MACHINE_FLAG_EDAT2; 229 if (test_facility(3)) 230 S390_lowcore.machine_flags |= MACHINE_FLAG_IDTE; 231 if (test_facility(50) && test_facility(73)) { 232 S390_lowcore.machine_flags |= MACHINE_FLAG_TE; 233 __ctl_set_bit(0, 55); 234 } 235 if (test_facility(51)) 236 S390_lowcore.machine_flags |= MACHINE_FLAG_TLB_LC; 237 if (test_facility(129)) { 238 S390_lowcore.machine_flags |= MACHINE_FLAG_VX; 239 __ctl_set_bit(0, 17); 240 } 241 if (test_facility(130)) { 242 S390_lowcore.machine_flags |= MACHINE_FLAG_NX; 243 __ctl_set_bit(0, 20); 244 } 245 if (test_facility(133)) 246 S390_lowcore.machine_flags |= MACHINE_FLAG_GS; 247 if (test_facility(139) && (tod_clock_base[1] & 0x80)) { 248 /* Enabled signed clock comparator comparisons */ 249 S390_lowcore.machine_flags |= MACHINE_FLAG_SCC; 250 clock_comparator_max = -1ULL >> 1; 251 __ctl_set_bit(0, 53); 252 } 253 } 254 255 static inline void save_vector_registers(void) 256 { 257 #ifdef CONFIG_CRASH_DUMP 258 if (test_facility(129)) 259 save_vx_regs(boot_cpu_vector_save_area); 260 #endif 261 } 262 263 static int __init disable_vector_extension(char *str) 264 { 265 S390_lowcore.machine_flags &= ~MACHINE_FLAG_VX; 266 __ctl_clear_bit(0, 17); 267 return 0; 268 } 269 early_param("novx", disable_vector_extension); 270 271 static int __init noexec_setup(char *str) 272 { 273 bool enabled; 274 int rc; 275 276 rc = kstrtobool(str, &enabled); 277 if (!rc && !enabled) { 278 /* Disable no-execute support */ 279 S390_lowcore.machine_flags &= ~MACHINE_FLAG_NX; 280 __ctl_clear_bit(0, 20); 281 } 282 return rc; 283 } 284 early_param("noexec", noexec_setup); 285 286 static int __init cad_setup(char *str) 287 { 288 bool enabled; 289 int rc; 290 291 rc = kstrtobool(str, &enabled); 292 if (!rc && enabled && test_facility(128)) 293 /* Enable problem state CAD. */ 294 __ctl_set_bit(2, 3); 295 return rc; 296 } 297 early_param("cad", cad_setup); 298 299 char __bootdata(early_command_line)[COMMAND_LINE_SIZE]; 300 static void __init setup_boot_command_line(void) 301 { 302 /* copy arch command line */ 303 strlcpy(boot_command_line, early_command_line, ARCH_COMMAND_LINE_SIZE); 304 } 305 306 static void __init check_image_bootable(void) 307 { 308 if (!memcmp(EP_STRING, (void *)EP_OFFSET, strlen(EP_STRING))) 309 return; 310 311 sclp_early_printk("Linux kernel boot failure: An attempt to boot a vmlinux ELF image failed.\n"); 312 sclp_early_printk("This image does not contain all parts necessary for starting up. Use\n"); 313 sclp_early_printk("bzImage or arch/s390/boot/compressed/vmlinux instead.\n"); 314 disabled_wait(); 315 } 316 317 void __init startup_init(void) 318 { 319 reset_tod_clock(); 320 check_image_bootable(); 321 time_early_init(); 322 init_kernel_storage_key(); 323 lockdep_off(); 324 setup_lowcore_early(); 325 setup_facility_list(); 326 detect_machine_type(); 327 setup_arch_string(); 328 setup_boot_command_line(); 329 detect_diag9c(); 330 detect_diag44(); 331 detect_machine_facilities(); 332 save_vector_registers(); 333 setup_topology(); 334 sclp_early_detect(); 335 lockdep_on(); 336 } 337