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 <asm/switch_to.h> 34 #include "entry.h" 35 36 int __bootdata(is_full_image); 37 38 static void __init reset_tod_clock(void) 39 { 40 union tod_clock clk; 41 42 if (store_tod_clock_ext_cc(&clk) == 0) 43 return; 44 /* TOD clock not running. Set the clock to Unix Epoch. */ 45 if (set_tod_clock(TOD_UNIX_EPOCH) || store_tod_clock_ext_cc(&clk)) 46 disabled_wait(); 47 48 memset(&tod_clock_base, 0, sizeof(tod_clock_base)); 49 tod_clock_base.tod = TOD_UNIX_EPOCH; 50 S390_lowcore.last_update_clock = TOD_UNIX_EPOCH; 51 } 52 53 /* 54 * Initialize storage key for kernel pages 55 */ 56 static noinline __init void init_kernel_storage_key(void) 57 { 58 #if PAGE_DEFAULT_KEY 59 unsigned long end_pfn, init_pfn; 60 61 end_pfn = PFN_UP(__pa(_end)); 62 63 for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++) 64 page_set_storage_key(init_pfn << PAGE_SHIFT, 65 PAGE_DEFAULT_KEY, 0); 66 #endif 67 } 68 69 static __initdata char sysinfo_page[PAGE_SIZE] __aligned(PAGE_SIZE); 70 71 static noinline __init void detect_machine_type(void) 72 { 73 struct sysinfo_3_2_2 *vmms = (struct sysinfo_3_2_2 *)&sysinfo_page; 74 75 /* Check current-configuration-level */ 76 if (stsi(NULL, 0, 0, 0) <= 2) { 77 S390_lowcore.machine_flags |= MACHINE_FLAG_LPAR; 78 return; 79 } 80 /* Get virtual-machine cpu information. */ 81 if (stsi(vmms, 3, 2, 2) || !vmms->count) 82 return; 83 84 /* Detect known hypervisors */ 85 if (!memcmp(vmms->vm[0].cpi, "\xd2\xe5\xd4", 3)) 86 S390_lowcore.machine_flags |= MACHINE_FLAG_KVM; 87 else if (!memcmp(vmms->vm[0].cpi, "\xa9\x61\xe5\xd4", 4)) 88 S390_lowcore.machine_flags |= MACHINE_FLAG_VM; 89 } 90 91 /* Remove leading, trailing and double whitespace. */ 92 static inline void strim_all(char *str) 93 { 94 char *s; 95 96 s = strim(str); 97 if (s != str) 98 memmove(str, s, strlen(s)); 99 while (*str) { 100 if (!isspace(*str++)) 101 continue; 102 if (isspace(*str)) { 103 s = skip_spaces(str); 104 memmove(str, s, strlen(s) + 1); 105 } 106 } 107 } 108 109 static noinline __init void setup_arch_string(void) 110 { 111 struct sysinfo_1_1_1 *mach = (struct sysinfo_1_1_1 *)&sysinfo_page; 112 struct sysinfo_3_2_2 *vm = (struct sysinfo_3_2_2 *)&sysinfo_page; 113 char mstr[80], hvstr[17]; 114 115 if (stsi(mach, 1, 1, 1)) 116 return; 117 EBCASC(mach->manufacturer, sizeof(mach->manufacturer)); 118 EBCASC(mach->type, sizeof(mach->type)); 119 EBCASC(mach->model, sizeof(mach->model)); 120 EBCASC(mach->model_capacity, sizeof(mach->model_capacity)); 121 sprintf(mstr, "%-16.16s %-4.4s %-16.16s %-16.16s", 122 mach->manufacturer, mach->type, 123 mach->model, mach->model_capacity); 124 strim_all(mstr); 125 if (stsi(vm, 3, 2, 2) == 0 && vm->count) { 126 EBCASC(vm->vm[0].cpi, sizeof(vm->vm[0].cpi)); 127 sprintf(hvstr, "%-16.16s", vm->vm[0].cpi); 128 strim_all(hvstr); 129 } else { 130 sprintf(hvstr, "%s", 131 MACHINE_IS_LPAR ? "LPAR" : 132 MACHINE_IS_VM ? "z/VM" : 133 MACHINE_IS_KVM ? "KVM" : "unknown"); 134 } 135 dump_stack_set_arch_desc("%s (%s)", mstr, hvstr); 136 } 137 138 static __init void setup_topology(void) 139 { 140 int max_mnest; 141 142 if (!test_facility(11)) 143 return; 144 S390_lowcore.machine_flags |= MACHINE_FLAG_TOPOLOGY; 145 for (max_mnest = 6; max_mnest > 1; max_mnest--) { 146 if (stsi(&sysinfo_page, 15, 1, max_mnest) == 0) 147 break; 148 } 149 topology_max_mnest = max_mnest; 150 } 151 152 static void early_pgm_check_handler(void) 153 { 154 const struct exception_table_entry *fixup; 155 unsigned long cr0, cr0_new; 156 unsigned long addr; 157 158 addr = S390_lowcore.program_old_psw.addr; 159 fixup = s390_search_extables(addr); 160 if (!fixup) 161 disabled_wait(); 162 /* Disable low address protection before storing into lowcore. */ 163 __ctl_store(cr0, 0, 0); 164 cr0_new = cr0 & ~(1UL << 28); 165 __ctl_load(cr0_new, 0, 0); 166 S390_lowcore.program_old_psw.addr = extable_fixup(fixup); 167 __ctl_load(cr0, 0, 0); 168 } 169 170 static noinline __init void setup_lowcore_early(void) 171 { 172 psw_t psw; 173 174 psw.addr = (unsigned long)s390_base_pgm_handler; 175 psw.mask = PSW_MASK_BASE | PSW_DEFAULT_KEY | PSW_MASK_EA | PSW_MASK_BA; 176 if (IS_ENABLED(CONFIG_KASAN)) 177 psw.mask |= PSW_MASK_DAT; 178 S390_lowcore.program_new_psw = psw; 179 s390_base_pgm_handler_fn = early_pgm_check_handler; 180 S390_lowcore.preempt_count = INIT_PREEMPT_COUNT; 181 } 182 183 static noinline __init void setup_facility_list(void) 184 { 185 memcpy(alt_stfle_fac_list, stfle_fac_list, sizeof(alt_stfle_fac_list)); 186 if (!IS_ENABLED(CONFIG_KERNEL_NOBP)) 187 __clear_facility(82, alt_stfle_fac_list); 188 } 189 190 static __init void detect_diag9c(void) 191 { 192 unsigned int cpu_address; 193 int rc; 194 195 cpu_address = stap(); 196 diag_stat_inc(DIAG_STAT_X09C); 197 asm volatile( 198 " diag %2,0,0x9c\n" 199 "0: la %0,0\n" 200 "1:\n" 201 EX_TABLE(0b,1b) 202 : "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc"); 203 if (!rc) 204 S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG9C; 205 } 206 207 static __init void detect_machine_facilities(void) 208 { 209 if (test_facility(8)) { 210 S390_lowcore.machine_flags |= MACHINE_FLAG_EDAT1; 211 __ctl_set_bit(0, 23); 212 } 213 if (test_facility(78)) 214 S390_lowcore.machine_flags |= MACHINE_FLAG_EDAT2; 215 if (test_facility(3)) 216 S390_lowcore.machine_flags |= MACHINE_FLAG_IDTE; 217 if (test_facility(50) && test_facility(73)) { 218 S390_lowcore.machine_flags |= MACHINE_FLAG_TE; 219 __ctl_set_bit(0, 55); 220 } 221 if (test_facility(51)) 222 S390_lowcore.machine_flags |= MACHINE_FLAG_TLB_LC; 223 if (test_facility(129)) { 224 S390_lowcore.machine_flags |= MACHINE_FLAG_VX; 225 __ctl_set_bit(0, 17); 226 } 227 if (test_facility(130) && !noexec_disabled) { 228 S390_lowcore.machine_flags |= MACHINE_FLAG_NX; 229 __ctl_set_bit(0, 20); 230 } 231 if (test_facility(133)) 232 S390_lowcore.machine_flags |= MACHINE_FLAG_GS; 233 if (test_facility(139) && (tod_clock_base.tod >> 63)) { 234 /* Enabled signed clock comparator comparisons */ 235 S390_lowcore.machine_flags |= MACHINE_FLAG_SCC; 236 clock_comparator_max = -1ULL >> 1; 237 __ctl_set_bit(0, 53); 238 } 239 if (IS_ENABLED(CONFIG_PCI) && test_facility(153)) { 240 S390_lowcore.machine_flags |= MACHINE_FLAG_PCI_MIO; 241 /* the control bit is set during PCI initialization */ 242 } 243 } 244 245 static inline void save_vector_registers(void) 246 { 247 #ifdef CONFIG_CRASH_DUMP 248 if (test_facility(129)) 249 save_vx_regs(boot_cpu_vector_save_area); 250 #endif 251 } 252 253 static inline void setup_control_registers(void) 254 { 255 unsigned long reg; 256 257 __ctl_store(reg, 0, 0); 258 reg |= CR0_LOW_ADDRESS_PROTECTION; 259 reg |= CR0_EMERGENCY_SIGNAL_SUBMASK; 260 reg |= CR0_EXTERNAL_CALL_SUBMASK; 261 __ctl_load(reg, 0, 0); 262 } 263 264 static inline void setup_access_registers(void) 265 { 266 unsigned int acrs[NUM_ACRS] = { 0 }; 267 268 restore_access_regs(acrs); 269 } 270 271 static int __init disable_vector_extension(char *str) 272 { 273 S390_lowcore.machine_flags &= ~MACHINE_FLAG_VX; 274 __ctl_clear_bit(0, 17); 275 return 0; 276 } 277 early_param("novx", disable_vector_extension); 278 279 char __bootdata(early_command_line)[COMMAND_LINE_SIZE]; 280 static void __init setup_boot_command_line(void) 281 { 282 /* copy arch command line */ 283 strlcpy(boot_command_line, early_command_line, ARCH_COMMAND_LINE_SIZE); 284 } 285 286 static void __init check_image_bootable(void) 287 { 288 if (is_full_image) 289 return; 290 291 sclp_early_printk("Linux kernel boot failure: An attempt to boot a vmlinux ELF image failed.\n"); 292 sclp_early_printk("This image does not contain all parts necessary for starting up. Use\n"); 293 sclp_early_printk("bzImage or arch/s390/boot/compressed/vmlinux instead.\n"); 294 disabled_wait(); 295 } 296 297 void __init startup_init(void) 298 { 299 reset_tod_clock(); 300 check_image_bootable(); 301 time_early_init(); 302 init_kernel_storage_key(); 303 lockdep_off(); 304 setup_lowcore_early(); 305 setup_facility_list(); 306 detect_machine_type(); 307 setup_arch_string(); 308 setup_boot_command_line(); 309 detect_diag9c(); 310 detect_machine_facilities(); 311 save_vector_registers(); 312 setup_topology(); 313 sclp_early_detect(); 314 setup_control_registers(); 315 setup_access_registers(); 316 lockdep_on(); 317 } 318