1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright IBM Corp. 2007, 2009
4 * Author(s): Hongjie Yang <hongjie@us.ibm.com>,
5 */
6
7 #define KMSG_COMPONENT "setup"
8 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
9
10 #include <linux/sched/debug.h>
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/asm-extable.h>
22 #include <linux/memblock.h>
23 #include <asm/access-regs.h>
24 #include <asm/diag.h>
25 #include <asm/ebcdic.h>
26 #include <asm/fpu.h>
27 #include <asm/ipl.h>
28 #include <asm/lowcore.h>
29 #include <asm/processor.h>
30 #include <asm/sections.h>
31 #include <asm/setup.h>
32 #include <asm/sysinfo.h>
33 #include <asm/cpcmd.h>
34 #include <asm/sclp.h>
35 #include <asm/facility.h>
36 #include <asm/boot_data.h>
37 #include "entry.h"
38
39 #define decompressor_handled_param(param) \
40 static int __init ignore_decompressor_param_##param(char *s) \
41 { \
42 return 0; \
43 } \
44 early_param(#param, ignore_decompressor_param_##param)
45
46 decompressor_handled_param(mem);
47 decompressor_handled_param(vmalloc);
48 decompressor_handled_param(dfltcc);
49 decompressor_handled_param(facilities);
50 decompressor_handled_param(nokaslr);
51 decompressor_handled_param(cmma);
52 decompressor_handled_param(relocate_lowcore);
53 decompressor_handled_param(bootdebug);
54 #if IS_ENABLED(CONFIG_KVM)
55 decompressor_handled_param(prot_virt);
56 #endif
57
kasan_early_init(void)58 static void __init kasan_early_init(void)
59 {
60 #ifdef CONFIG_KASAN
61 init_task.kasan_depth = 0;
62 pr_info("KernelAddressSanitizer initialized\n");
63 #endif
64 }
65
reset_tod_clock(void)66 static void __init reset_tod_clock(void)
67 {
68 union tod_clock clk;
69
70 if (store_tod_clock_ext_cc(&clk) == 0)
71 return;
72 /* TOD clock not running. Set the clock to Unix Epoch. */
73 if (set_tod_clock(TOD_UNIX_EPOCH) || store_tod_clock_ext_cc(&clk))
74 disabled_wait();
75
76 memset(&tod_clock_base, 0, sizeof(tod_clock_base));
77 tod_clock_base.tod = TOD_UNIX_EPOCH;
78 get_lowcore()->last_update_clock = TOD_UNIX_EPOCH;
79 }
80
81 /*
82 * Initialize storage key for kernel pages
83 */
init_kernel_storage_key(void)84 static noinline __init void init_kernel_storage_key(void)
85 {
86 #if PAGE_DEFAULT_KEY
87 unsigned long end_pfn, init_pfn;
88
89 end_pfn = PFN_UP(__pa(_end));
90
91 for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++)
92 page_set_storage_key(init_pfn << PAGE_SHIFT,
93 PAGE_DEFAULT_KEY, 0);
94 #endif
95 }
96
97 static __initdata char sysinfo_page[PAGE_SIZE] __aligned(PAGE_SIZE);
98
detect_machine_type(void)99 static noinline __init void detect_machine_type(void)
100 {
101 struct sysinfo_3_2_2 *vmms = (struct sysinfo_3_2_2 *)&sysinfo_page;
102
103 /* Check current-configuration-level */
104 if (stsi(NULL, 0, 0, 0) <= 2) {
105 get_lowcore()->machine_flags |= MACHINE_FLAG_LPAR;
106 return;
107 }
108 /* Get virtual-machine cpu information. */
109 if (stsi(vmms, 3, 2, 2) || !vmms->count)
110 return;
111
112 /* Detect known hypervisors */
113 if (!memcmp(vmms->vm[0].cpi, "\xd2\xe5\xd4", 3))
114 get_lowcore()->machine_flags |= MACHINE_FLAG_KVM;
115 else if (!memcmp(vmms->vm[0].cpi, "\xa9\x61\xe5\xd4", 4))
116 get_lowcore()->machine_flags |= MACHINE_FLAG_VM;
117 }
118
119 /* Remove leading, trailing and double whitespace. */
strim_all(char * str)120 static inline void strim_all(char *str)
121 {
122 char *s;
123
124 s = strim(str);
125 if (s != str)
126 memmove(str, s, strlen(s));
127 while (*str) {
128 if (!isspace(*str++))
129 continue;
130 if (isspace(*str)) {
131 s = skip_spaces(str);
132 memmove(str, s, strlen(s) + 1);
133 }
134 }
135 }
136
setup_arch_string(void)137 static noinline __init void setup_arch_string(void)
138 {
139 struct sysinfo_1_1_1 *mach = (struct sysinfo_1_1_1 *)&sysinfo_page;
140 struct sysinfo_3_2_2 *vm = (struct sysinfo_3_2_2 *)&sysinfo_page;
141 char mstr[80], hvstr[17];
142
143 if (stsi(mach, 1, 1, 1))
144 return;
145 EBCASC(mach->manufacturer, sizeof(mach->manufacturer));
146 EBCASC(mach->type, sizeof(mach->type));
147 EBCASC(mach->model, sizeof(mach->model));
148 EBCASC(mach->model_capacity, sizeof(mach->model_capacity));
149 sprintf(mstr, "%-16.16s %-4.4s %-16.16s %-16.16s",
150 mach->manufacturer, mach->type,
151 mach->model, mach->model_capacity);
152 strim_all(mstr);
153 if (stsi(vm, 3, 2, 2) == 0 && vm->count) {
154 EBCASC(vm->vm[0].cpi, sizeof(vm->vm[0].cpi));
155 sprintf(hvstr, "%-16.16s", vm->vm[0].cpi);
156 strim_all(hvstr);
157 } else {
158 sprintf(hvstr, "%s",
159 MACHINE_IS_LPAR ? "LPAR" :
160 MACHINE_IS_VM ? "z/VM" :
161 MACHINE_IS_KVM ? "KVM" : "unknown");
162 }
163 dump_stack_set_arch_desc("%s (%s)", mstr, hvstr);
164 }
165
setup_topology(void)166 static __init void setup_topology(void)
167 {
168 int max_mnest;
169
170 if (!test_facility(11))
171 return;
172 get_lowcore()->machine_flags |= MACHINE_FLAG_TOPOLOGY;
173 for (max_mnest = 6; max_mnest > 1; max_mnest--) {
174 if (stsi(&sysinfo_page, 15, 1, max_mnest) == 0)
175 break;
176 }
177 topology_max_mnest = max_mnest;
178 }
179
__do_early_pgm_check(struct pt_regs * regs)180 void __init __do_early_pgm_check(struct pt_regs *regs)
181 {
182 struct lowcore *lc = get_lowcore();
183 unsigned long ip;
184
185 regs->int_code = lc->pgm_int_code;
186 regs->int_parm_long = lc->trans_exc_code;
187 ip = __rewind_psw(regs->psw, regs->int_code >> 16);
188
189 /* Monitor Event? Might be a warning */
190 if ((regs->int_code & PGM_INT_CODE_MASK) == 0x40) {
191 if (report_bug(ip, regs) == BUG_TRAP_TYPE_WARN)
192 return;
193 }
194 if (fixup_exception(regs))
195 return;
196 /*
197 * Unhandled exception - system cannot continue but try to get some
198 * helpful messages to the console. Use early_printk() to print
199 * some basic information in case it is too early for printk().
200 */
201 register_early_console();
202 early_printk("PANIC: early exception %04x PSW: %016lx %016lx\n",
203 regs->int_code & 0xffff, regs->psw.mask, regs->psw.addr);
204 show_regs(regs);
205 disabled_wait();
206 }
207
setup_lowcore_early(void)208 static noinline __init void setup_lowcore_early(void)
209 {
210 struct lowcore *lc = get_lowcore();
211 psw_t psw;
212
213 psw.addr = (unsigned long)early_pgm_check_handler;
214 psw.mask = PSW_KERNEL_BITS;
215 lc->program_new_psw = psw;
216 lc->preempt_count = INIT_PREEMPT_COUNT;
217 lc->return_lpswe = gen_lpswe(__LC_RETURN_PSW);
218 lc->return_mcck_lpswe = gen_lpswe(__LC_RETURN_MCCK_PSW);
219 }
220
detect_diag9c(void)221 static __init void detect_diag9c(void)
222 {
223 unsigned int cpu_address;
224 int rc;
225
226 cpu_address = stap();
227 diag_stat_inc(DIAG_STAT_X09C);
228 asm volatile(
229 " diag %2,0,0x9c\n"
230 "0: la %0,0\n"
231 "1:\n"
232 EX_TABLE(0b,1b)
233 : "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc");
234 if (!rc)
235 get_lowcore()->machine_flags |= MACHINE_FLAG_DIAG9C;
236 }
237
detect_machine_facilities(void)238 static __init void detect_machine_facilities(void)
239 {
240 if (test_facility(8)) {
241 get_lowcore()->machine_flags |= MACHINE_FLAG_EDAT1;
242 system_ctl_set_bit(0, CR0_EDAT_BIT);
243 }
244 if (test_facility(78))
245 get_lowcore()->machine_flags |= MACHINE_FLAG_EDAT2;
246 if (test_facility(3))
247 get_lowcore()->machine_flags |= MACHINE_FLAG_IDTE;
248 if (test_facility(50) && test_facility(73)) {
249 get_lowcore()->machine_flags |= MACHINE_FLAG_TE;
250 system_ctl_set_bit(0, CR0_TRANSACTIONAL_EXECUTION_BIT);
251 }
252 if (test_facility(51))
253 get_lowcore()->machine_flags |= MACHINE_FLAG_TLB_LC;
254 if (test_facility(129))
255 system_ctl_set_bit(0, CR0_VECTOR_BIT);
256 if (test_facility(130))
257 get_lowcore()->machine_flags |= MACHINE_FLAG_NX;
258 if (test_facility(133))
259 get_lowcore()->machine_flags |= MACHINE_FLAG_GS;
260 if (test_facility(139) && (tod_clock_base.tod >> 63)) {
261 /* Enabled signed clock comparator comparisons */
262 get_lowcore()->machine_flags |= MACHINE_FLAG_SCC;
263 clock_comparator_max = -1ULL >> 1;
264 system_ctl_set_bit(0, CR0_CLOCK_COMPARATOR_SIGN_BIT);
265 }
266 if (IS_ENABLED(CONFIG_PCI) && test_facility(153)) {
267 get_lowcore()->machine_flags |= MACHINE_FLAG_PCI_MIO;
268 /* the control bit is set during PCI initialization */
269 }
270 if (test_facility(194))
271 get_lowcore()->machine_flags |= MACHINE_FLAG_RDP;
272 if (test_facility(85))
273 get_lowcore()->machine_flags |= MACHINE_FLAG_SEQ_INSN;
274 }
275
save_vector_registers(void)276 static inline void save_vector_registers(void)
277 {
278 #ifdef CONFIG_CRASH_DUMP
279 if (test_facility(129))
280 save_vx_regs(boot_cpu_vector_save_area);
281 #endif
282 }
283
setup_low_address_protection(void)284 static inline void setup_low_address_protection(void)
285 {
286 system_ctl_set_bit(0, CR0_LOW_ADDRESS_PROTECTION_BIT);
287 }
288
setup_access_registers(void)289 static inline void setup_access_registers(void)
290 {
291 unsigned int acrs[NUM_ACRS] = { 0 };
292
293 restore_access_regs(acrs);
294 }
295
296 char __bootdata(early_command_line)[COMMAND_LINE_SIZE];
setup_boot_command_line(void)297 static void __init setup_boot_command_line(void)
298 {
299 /* copy arch command line */
300 strscpy(boot_command_line, early_command_line, COMMAND_LINE_SIZE);
301 }
302
sort_amode31_extable(void)303 static void __init sort_amode31_extable(void)
304 {
305 sort_extable(__start_amode31_ex_table, __stop_amode31_ex_table);
306 }
307
startup_init(void)308 void __init startup_init(void)
309 {
310 kasan_early_init();
311 reset_tod_clock();
312 time_early_init();
313 init_kernel_storage_key();
314 lockdep_off();
315 sort_amode31_extable();
316 setup_lowcore_early();
317 detect_machine_type();
318 setup_arch_string();
319 setup_boot_command_line();
320 detect_diag9c();
321 detect_machine_facilities();
322 save_vector_registers();
323 setup_topology();
324 sclp_early_detect();
325 setup_low_address_protection();
326 setup_access_registers();
327 lockdep_on();
328 }
329