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/compiler.h>
11#include <linux/init.h>
12#include <linux/errno.h>
13#include <linux/string.h>
14#include <linux/ctype.h>
15#include <linux/lockdep.h>
16#include <linux/extable.h>
17#include <linux/pfn.h>
18#include <linux/uaccess.h>
19#include <linux/kernel.h>
20#include <asm/asm-extable.h>
21#include <linux/memblock.h>
22#include <asm/access-regs.h>
23#include <asm/diag.h>
24#include <asm/ebcdic.h>
25#include <asm/fpu.h>
26#include <asm/ipl.h>
27#include <asm/lowcore.h>
28#include <asm/processor.h>
29#include <asm/sections.h>
30#include <asm/setup.h>
31#include <asm/sysinfo.h>
32#include <asm/cpcmd.h>
33#include <asm/sclp.h>
34#include <asm/facility.h>
35#include <asm/boot_data.h>
36#include "entry.h"
37
38#define decompressor_handled_param(param) \
39static int __init ignore_decompressor_param_##param(char *s) \
40{ \
41 return 0; \
42} \
43early_param(#param, ignore_decompressor_param_##param)
44
45decompressor_handled_param(mem);
46decompressor_handled_param(vmalloc);
47decompressor_handled_param(dfltcc);
48decompressor_handled_param(facilities);
49decompressor_handled_param(nokaslr);
50decompressor_handled_param(cmma);
51#if IS_ENABLED(CONFIG_KVM)
52decompressor_handled_param(prot_virt);
53#endif
54
55static void __init kasan_early_init(void)
56{
57#ifdef CONFIG_KASAN
58 init_task.kasan_depth = 0;
59 sclp_early_printk("KernelAddressSanitizer initialized\n");
60#endif
61}
62
63static void __init reset_tod_clock(void)
64{
65 union tod_clock clk;
66
67 if (store_tod_clock_ext_cc(&clk) == 0)
68 return;
69 /* TOD clock not running. Set the clock to Unix Epoch. */
70 if (set_tod_clock(TOD_UNIX_EPOCH) || store_tod_clock_ext_cc(&clk))
71 disabled_wait();
72
73 memset(&tod_clock_base, 0, sizeof(tod_clock_base));
74 tod_clock_base.tod = TOD_UNIX_EPOCH;
75 S390_lowcore.last_update_clock = TOD_UNIX_EPOCH;
76}
77
78/*
79 * Initialize storage key for kernel pages
80 */
81static noinline __init void init_kernel_storage_key(void)
82{
83#if PAGE_DEFAULT_KEY
84 unsigned long end_pfn, init_pfn;
85
86 end_pfn = PFN_UP(__pa(_end));
87
88 for (init_pfn = 0 ; init_pfn < end_pfn; init_pfn++)
89 page_set_storage_key(init_pfn << PAGE_SHIFT,
90 PAGE_DEFAULT_KEY, 0);
91#endif
92}
93
94static __initdata char sysinfo_page[PAGE_SIZE] __aligned(PAGE_SIZE);
95
96static noinline __init void detect_machine_type(void)
97{
98 struct sysinfo_3_2_2 *vmms = (struct sysinfo_3_2_2 *)&sysinfo_page;
99
100 /* Check current-configuration-level */
101 if (stsi(NULL, 0, 0, 0) <= 2) {
102 S390_lowcore.machine_flags |= MACHINE_FLAG_LPAR;
103 return;
104 }
105 /* Get virtual-machine cpu information. */
106 if (stsi(vmms, 3, 2, 2) || !vmms->count)
107 return;
108
109 /* Detect known hypervisors */
110 if (!memcmp(vmms->vm[0].cpi, "\xd2\xe5\xd4", 3))
111 S390_lowcore.machine_flags |= MACHINE_FLAG_KVM;
112 else if (!memcmp(vmms->vm[0].cpi, "\xa9\x61\xe5\xd4", 4))
113 S390_lowcore.machine_flags |= MACHINE_FLAG_VM;
114}
115
116/* Remove leading, trailing and double whitespace. */
117static inline void strim_all(char *str)
118{
119 char *s;
120
121 s = strim(str);
122 if (s != str)
123 memmove(str, s, strlen(s));
124 while (*str) {
125 if (!isspace(*str++))
126 continue;
127 if (isspace(*str)) {
128 s = skip_spaces(str);
129 memmove(str, s, strlen(s) + 1);
130 }
131 }
132}
133
134static noinline __init void setup_arch_string(void)
135{
136 struct sysinfo_1_1_1 *mach = (struct sysinfo_1_1_1 *)&sysinfo_page;
137 struct sysinfo_3_2_2 *vm = (struct sysinfo_3_2_2 *)&sysinfo_page;
138 char mstr[80], hvstr[17];
139
140 if (stsi(mach, 1, 1, 1))
141 return;
142 EBCASC(mach->manufacturer, sizeof(mach->manufacturer));
143 EBCASC(mach->type, sizeof(mach->type));
144 EBCASC(mach->model, sizeof(mach->model));
145 EBCASC(mach->model_capacity, sizeof(mach->model_capacity));
146 sprintf(buf: mstr, fmt: "%-16.16s %-4.4s %-16.16s %-16.16s",
147 mach->manufacturer, mach->type,
148 mach->model, mach->model_capacity);
149 strim_all(str: mstr);
150 if (stsi(vm, 3, 2, 2) == 0 && vm->count) {
151 EBCASC(vm->vm[0].cpi, sizeof(vm->vm[0].cpi));
152 sprintf(buf: hvstr, fmt: "%-16.16s", vm->vm[0].cpi);
153 strim_all(str: hvstr);
154 } else {
155 sprintf(buf: hvstr, fmt: "%s",
156 MACHINE_IS_LPAR ? "LPAR" :
157 MACHINE_IS_VM ? "z/VM" :
158 MACHINE_IS_KVM ? "KVM" : "unknown");
159 }
160 dump_stack_set_arch_desc(fmt: "%s (%s)", mstr, hvstr);
161}
162
163static __init void setup_topology(void)
164{
165 int max_mnest;
166
167 if (!test_facility(11))
168 return;
169 S390_lowcore.machine_flags |= MACHINE_FLAG_TOPOLOGY;
170 for (max_mnest = 6; max_mnest > 1; max_mnest--) {
171 if (stsi(&sysinfo_page, 15, 1, max_mnest) == 0)
172 break;
173 }
174 topology_max_mnest = max_mnest;
175}
176
177void __do_early_pgm_check(struct pt_regs *regs)
178{
179 if (!fixup_exception(regs))
180 disabled_wait();
181}
182
183static noinline __init void setup_lowcore_early(void)
184{
185 psw_t psw;
186
187 psw.addr = (unsigned long)early_pgm_check_handler;
188 psw.mask = PSW_KERNEL_BITS;
189 S390_lowcore.program_new_psw = psw;
190 S390_lowcore.preempt_count = INIT_PREEMPT_COUNT;
191}
192
193static noinline __init void setup_facility_list(void)
194{
195 memcpy(alt_stfle_fac_list, stfle_fac_list, sizeof(alt_stfle_fac_list));
196 if (!IS_ENABLED(CONFIG_KERNEL_NOBP))
197 __clear_facility(82, alt_stfle_fac_list);
198}
199
200static __init void detect_diag9c(void)
201{
202 unsigned int cpu_address;
203 int rc;
204
205 cpu_address = stap();
206 diag_stat_inc(DIAG_STAT_X09C);
207 asm volatile(
208 " diag %2,0,0x9c\n"
209 "0: la %0,0\n"
210 "1:\n"
211 EX_TABLE(0b,1b)
212 : "=d" (rc) : "0" (-EOPNOTSUPP), "d" (cpu_address) : "cc");
213 if (!rc)
214 S390_lowcore.machine_flags |= MACHINE_FLAG_DIAG9C;
215}
216
217static __init void detect_machine_facilities(void)
218{
219 if (test_facility(8)) {
220 S390_lowcore.machine_flags |= MACHINE_FLAG_EDAT1;
221 system_ctl_set_bit(0, CR0_EDAT_BIT);
222 }
223 if (test_facility(78))
224 S390_lowcore.machine_flags |= MACHINE_FLAG_EDAT2;
225 if (test_facility(3))
226 S390_lowcore.machine_flags |= MACHINE_FLAG_IDTE;
227 if (test_facility(50) && test_facility(73)) {
228 S390_lowcore.machine_flags |= MACHINE_FLAG_TE;
229 system_ctl_set_bit(0, CR0_TRANSACTIONAL_EXECUTION_BIT);
230 }
231 if (test_facility(51))
232 S390_lowcore.machine_flags |= MACHINE_FLAG_TLB_LC;
233 if (test_facility(129))
234 system_ctl_set_bit(0, CR0_VECTOR_BIT);
235 if (test_facility(130))
236 S390_lowcore.machine_flags |= MACHINE_FLAG_NX;
237 if (test_facility(133))
238 S390_lowcore.machine_flags |= MACHINE_FLAG_GS;
239 if (test_facility(139) && (tod_clock_base.tod >> 63)) {
240 /* Enabled signed clock comparator comparisons */
241 S390_lowcore.machine_flags |= MACHINE_FLAG_SCC;
242 clock_comparator_max = -1ULL >> 1;
243 system_ctl_set_bit(0, CR0_CLOCK_COMPARATOR_SIGN_BIT);
244 }
245 if (IS_ENABLED(CONFIG_PCI) && test_facility(153)) {
246 S390_lowcore.machine_flags |= MACHINE_FLAG_PCI_MIO;
247 /* the control bit is set during PCI initialization */
248 }
249 if (test_facility(194))
250 S390_lowcore.machine_flags |= MACHINE_FLAG_RDP;
251}
252
253static inline void save_vector_registers(void)
254{
255#ifdef CONFIG_CRASH_DUMP
256 if (test_facility(129))
257 save_vx_regs(boot_cpu_vector_save_area);
258#endif
259}
260
261static inline void setup_low_address_protection(void)
262{
263 system_ctl_set_bit(0, CR0_LOW_ADDRESS_PROTECTION_BIT);
264}
265
266static inline void setup_access_registers(void)
267{
268 unsigned int acrs[NUM_ACRS] = { 0 };
269
270 restore_access_regs(acrs);
271}
272
273char __bootdata(early_command_line)[COMMAND_LINE_SIZE];
274static void __init setup_boot_command_line(void)
275{
276 /* copy arch command line */
277 strscpy(boot_command_line, early_command_line, COMMAND_LINE_SIZE);
278}
279
280static void __init sort_amode31_extable(void)
281{
282 sort_extable(__start_amode31_ex_table, __stop_amode31_ex_table);
283}
284
285void __init startup_init(void)
286{
287 kasan_early_init();
288 reset_tod_clock();
289 time_early_init();
290 init_kernel_storage_key();
291 lockdep_off();
292 sort_amode31_extable();
293 setup_lowcore_early();
294 setup_facility_list();
295 detect_machine_type();
296 setup_arch_string();
297 setup_boot_command_line();
298 detect_diag9c();
299 detect_machine_facilities();
300 save_vector_registers();
301 setup_topology();
302 sclp_early_detect();
303 setup_low_address_protection();
304 setup_access_registers();
305 lockdep_on();
306}
307

source code of linux/arch/s390/kernel/early.c