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