1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright IBM Corp. 2008
4 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
5 */
6
7 #define KMSG_COMPONENT "cpu"
8 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
9
10 #include <linux/stop_machine.h>
11 #include <linux/bitops.h>
12 #include <linux/kernel.h>
13 #include <linux/random.h>
14 #include <linux/sched/mm.h>
15 #include <linux/init.h>
16 #include <linux/seq_file.h>
17 #include <linux/mm_types.h>
18 #include <linux/delay.h>
19 #include <linux/cpu.h>
20
21 #include <asm/diag.h>
22 #include <asm/facility.h>
23 #include <asm/elf.h>
24 #include <asm/lowcore.h>
25 #include <asm/param.h>
26 #include <asm/sclp.h>
27 #include <asm/smp.h>
28
29 unsigned long __read_mostly elf_hwcap;
30 char elf_platform[ELF_PLATFORM_SIZE];
31
32 struct cpu_info {
33 unsigned int cpu_mhz_dynamic;
34 unsigned int cpu_mhz_static;
35 struct cpuid cpu_id;
36 };
37
38 static DEFINE_PER_CPU(struct cpu_info, cpu_info);
39 static DEFINE_PER_CPU(int, cpu_relax_retry);
40
41 static bool machine_has_cpu_mhz;
42
cpu_detect_mhz_feature(void)43 void __init cpu_detect_mhz_feature(void)
44 {
45 if (test_facility(34) && __ecag(ECAG_CPU_ATTRIBUTE, 0) != -1UL)
46 machine_has_cpu_mhz = true;
47 }
48
update_cpu_mhz(void * arg)49 static void update_cpu_mhz(void *arg)
50 {
51 unsigned long mhz;
52 struct cpu_info *c;
53
54 mhz = __ecag(ECAG_CPU_ATTRIBUTE, 0);
55 c = this_cpu_ptr(&cpu_info);
56 c->cpu_mhz_dynamic = mhz >> 32;
57 c->cpu_mhz_static = mhz & 0xffffffff;
58 }
59
s390_update_cpu_mhz(void)60 void s390_update_cpu_mhz(void)
61 {
62 s390_adjust_jiffies();
63 if (machine_has_cpu_mhz)
64 on_each_cpu(update_cpu_mhz, NULL, 0);
65 }
66
stop_machine_yield(const struct cpumask * cpumask)67 void notrace stop_machine_yield(const struct cpumask *cpumask)
68 {
69 int cpu, this_cpu;
70
71 this_cpu = smp_processor_id();
72 if (__this_cpu_inc_return(cpu_relax_retry) >= spin_retry) {
73 __this_cpu_write(cpu_relax_retry, 0);
74 cpu = cpumask_next_wrap(this_cpu, cpumask, this_cpu, false);
75 if (cpu >= nr_cpu_ids)
76 return;
77 if (arch_vcpu_is_preempted(cpu))
78 smp_yield_cpu(cpu);
79 }
80 }
81
82 /*
83 * cpu_init - initializes state that is per-CPU.
84 */
cpu_init(void)85 void cpu_init(void)
86 {
87 struct cpuid *id = this_cpu_ptr(&cpu_info.cpu_id);
88
89 get_cpu_id(id);
90 if (machine_has_cpu_mhz)
91 update_cpu_mhz(NULL);
92 mmgrab(&init_mm);
93 current->active_mm = &init_mm;
94 BUG_ON(current->mm);
95 enter_lazy_tlb(&init_mm, current);
96 }
97
show_facilities(struct seq_file * m)98 static void show_facilities(struct seq_file *m)
99 {
100 unsigned int bit;
101
102 seq_puts(m, "facilities :");
103 for_each_set_bit_inv(bit, (long *)&stfle_fac_list, MAX_FACILITY_BIT)
104 seq_printf(m, " %d", bit);
105 seq_putc(m, '\n');
106 }
107
show_cpu_summary(struct seq_file * m,void * v)108 static void show_cpu_summary(struct seq_file *m, void *v)
109 {
110 static const char *hwcap_str[] = {
111 [HWCAP_NR_ESAN3] = "esan3",
112 [HWCAP_NR_ZARCH] = "zarch",
113 [HWCAP_NR_STFLE] = "stfle",
114 [HWCAP_NR_MSA] = "msa",
115 [HWCAP_NR_LDISP] = "ldisp",
116 [HWCAP_NR_EIMM] = "eimm",
117 [HWCAP_NR_DFP] = "dfp",
118 [HWCAP_NR_HPAGE] = "edat",
119 [HWCAP_NR_ETF3EH] = "etf3eh",
120 [HWCAP_NR_HIGH_GPRS] = "highgprs",
121 [HWCAP_NR_TE] = "te",
122 [HWCAP_NR_VXRS] = "vx",
123 [HWCAP_NR_VXRS_BCD] = "vxd",
124 [HWCAP_NR_VXRS_EXT] = "vxe",
125 [HWCAP_NR_GS] = "gs",
126 [HWCAP_NR_VXRS_EXT2] = "vxe2",
127 [HWCAP_NR_VXRS_PDE] = "vxp",
128 [HWCAP_NR_SORT] = "sort",
129 [HWCAP_NR_DFLT] = "dflt",
130 [HWCAP_NR_VXRS_PDE2] = "vxp2",
131 [HWCAP_NR_NNPA] = "nnpa",
132 [HWCAP_NR_PCI_MIO] = "pcimio",
133 [HWCAP_NR_SIE] = "sie",
134 };
135 int i, cpu;
136
137 BUILD_BUG_ON(ARRAY_SIZE(hwcap_str) != HWCAP_NR_MAX);
138 seq_printf(m, "vendor_id : IBM/S390\n"
139 "# processors : %i\n"
140 "bogomips per cpu: %lu.%02lu\n",
141 num_online_cpus(), loops_per_jiffy/(500000/HZ),
142 (loops_per_jiffy/(5000/HZ))%100);
143 seq_printf(m, "max thread id : %d\n", smp_cpu_mtid);
144 seq_puts(m, "features\t: ");
145 for (i = 0; i < ARRAY_SIZE(hwcap_str); i++)
146 if (hwcap_str[i] && (elf_hwcap & (1UL << i)))
147 seq_printf(m, "%s ", hwcap_str[i]);
148 seq_puts(m, "\n");
149 show_facilities(m);
150 show_cacheinfo(m);
151 for_each_online_cpu(cpu) {
152 struct cpuid *id = &per_cpu(cpu_info.cpu_id, cpu);
153
154 seq_printf(m, "processor %d: "
155 "version = %02X, "
156 "identification = %06X, "
157 "machine = %04X\n",
158 cpu, id->version, id->ident, id->machine);
159 }
160 }
161
setup_hwcaps(void)162 static int __init setup_hwcaps(void)
163 {
164 /* instructions named N3, "backported" to esa-mode */
165 elf_hwcap |= HWCAP_ESAN3;
166
167 /* z/Architecture mode active */
168 elf_hwcap |= HWCAP_ZARCH;
169
170 /* store-facility-list-extended */
171 if (test_facility(7))
172 elf_hwcap |= HWCAP_STFLE;
173
174 /* message-security assist */
175 if (test_facility(17))
176 elf_hwcap |= HWCAP_MSA;
177
178 /* long-displacement */
179 if (test_facility(19))
180 elf_hwcap |= HWCAP_LDISP;
181
182 /* extended-immediate */
183 elf_hwcap |= HWCAP_EIMM;
184
185 /* extended-translation facility 3 enhancement */
186 if (test_facility(22) && test_facility(30))
187 elf_hwcap |= HWCAP_ETF3EH;
188
189 /* decimal floating point & perform floating point operation */
190 if (test_facility(42) && test_facility(44))
191 elf_hwcap |= HWCAP_DFP;
192
193 /* huge page support */
194 if (MACHINE_HAS_EDAT1)
195 elf_hwcap |= HWCAP_HPAGE;
196
197 /* 64-bit register support for 31-bit processes */
198 elf_hwcap |= HWCAP_HIGH_GPRS;
199
200 /* transactional execution */
201 if (MACHINE_HAS_TE)
202 elf_hwcap |= HWCAP_TE;
203
204 /*
205 * Vector extension can be disabled with the "novx" parameter.
206 * Use MACHINE_HAS_VX instead of facility bit 129.
207 */
208 if (MACHINE_HAS_VX) {
209 elf_hwcap |= HWCAP_VXRS;
210 if (test_facility(134))
211 elf_hwcap |= HWCAP_VXRS_BCD;
212 if (test_facility(135))
213 elf_hwcap |= HWCAP_VXRS_EXT;
214 if (test_facility(148))
215 elf_hwcap |= HWCAP_VXRS_EXT2;
216 if (test_facility(152))
217 elf_hwcap |= HWCAP_VXRS_PDE;
218 if (test_facility(192))
219 elf_hwcap |= HWCAP_VXRS_PDE2;
220 }
221
222 if (test_facility(150))
223 elf_hwcap |= HWCAP_SORT;
224
225 if (test_facility(151))
226 elf_hwcap |= HWCAP_DFLT;
227
228 if (test_facility(165))
229 elf_hwcap |= HWCAP_NNPA;
230
231 /* guarded storage */
232 if (MACHINE_HAS_GS)
233 elf_hwcap |= HWCAP_GS;
234
235 if (MACHINE_HAS_PCI_MIO)
236 elf_hwcap |= HWCAP_PCI_MIO;
237
238 /* virtualization support */
239 if (sclp.has_sief2)
240 elf_hwcap |= HWCAP_SIE;
241
242 return 0;
243 }
244 arch_initcall(setup_hwcaps);
245
setup_elf_platform(void)246 static int __init setup_elf_platform(void)
247 {
248 struct cpuid cpu_id;
249
250 get_cpu_id(&cpu_id);
251 add_device_randomness(&cpu_id, sizeof(cpu_id));
252 switch (cpu_id.machine) {
253 default: /* Use "z10" as default. */
254 strcpy(elf_platform, "z10");
255 break;
256 case 0x2817:
257 case 0x2818:
258 strcpy(elf_platform, "z196");
259 break;
260 case 0x2827:
261 case 0x2828:
262 strcpy(elf_platform, "zEC12");
263 break;
264 case 0x2964:
265 case 0x2965:
266 strcpy(elf_platform, "z13");
267 break;
268 case 0x3906:
269 case 0x3907:
270 strcpy(elf_platform, "z14");
271 break;
272 case 0x8561:
273 case 0x8562:
274 strcpy(elf_platform, "z15");
275 break;
276 case 0x3931:
277 case 0x3932:
278 strcpy(elf_platform, "z16");
279 break;
280 }
281 return 0;
282 }
283 arch_initcall(setup_elf_platform);
284
show_cpu_topology(struct seq_file * m,unsigned long n)285 static void show_cpu_topology(struct seq_file *m, unsigned long n)
286 {
287 #ifdef CONFIG_SCHED_TOPOLOGY
288 seq_printf(m, "physical id : %d\n", topology_physical_package_id(n));
289 seq_printf(m, "core id : %d\n", topology_core_id(n));
290 seq_printf(m, "book id : %d\n", topology_book_id(n));
291 seq_printf(m, "drawer id : %d\n", topology_drawer_id(n));
292 seq_printf(m, "dedicated : %d\n", topology_cpu_dedicated(n));
293 seq_printf(m, "address : %d\n", smp_cpu_get_cpu_address(n));
294 seq_printf(m, "siblings : %d\n", cpumask_weight(topology_core_cpumask(n)));
295 seq_printf(m, "cpu cores : %d\n", topology_booted_cores(n));
296 #endif /* CONFIG_SCHED_TOPOLOGY */
297 }
298
show_cpu_ids(struct seq_file * m,unsigned long n)299 static void show_cpu_ids(struct seq_file *m, unsigned long n)
300 {
301 struct cpuid *id = &per_cpu(cpu_info.cpu_id, n);
302
303 seq_printf(m, "version : %02X\n", id->version);
304 seq_printf(m, "identification : %06X\n", id->ident);
305 seq_printf(m, "machine : %04X\n", id->machine);
306 }
307
show_cpu_mhz(struct seq_file * m,unsigned long n)308 static void show_cpu_mhz(struct seq_file *m, unsigned long n)
309 {
310 struct cpu_info *c = per_cpu_ptr(&cpu_info, n);
311
312 if (!machine_has_cpu_mhz)
313 return;
314 seq_printf(m, "cpu MHz dynamic : %d\n", c->cpu_mhz_dynamic);
315 seq_printf(m, "cpu MHz static : %d\n", c->cpu_mhz_static);
316 }
317
318 /*
319 * show_cpuinfo - Get information on one CPU for use by procfs.
320 */
show_cpuinfo(struct seq_file * m,void * v)321 static int show_cpuinfo(struct seq_file *m, void *v)
322 {
323 unsigned long n = (unsigned long) v - 1;
324 unsigned long first = cpumask_first(cpu_online_mask);
325
326 if (n == first)
327 show_cpu_summary(m, v);
328 seq_printf(m, "\ncpu number : %ld\n", n);
329 show_cpu_topology(m, n);
330 show_cpu_ids(m, n);
331 show_cpu_mhz(m, n);
332 return 0;
333 }
334
c_update(loff_t * pos)335 static inline void *c_update(loff_t *pos)
336 {
337 if (*pos)
338 *pos = cpumask_next(*pos - 1, cpu_online_mask);
339 else
340 *pos = cpumask_first(cpu_online_mask);
341 return *pos < nr_cpu_ids ? (void *)*pos + 1 : NULL;
342 }
343
c_start(struct seq_file * m,loff_t * pos)344 static void *c_start(struct seq_file *m, loff_t *pos)
345 {
346 cpus_read_lock();
347 return c_update(pos);
348 }
349
c_next(struct seq_file * m,void * v,loff_t * pos)350 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
351 {
352 ++*pos;
353 return c_update(pos);
354 }
355
c_stop(struct seq_file * m,void * v)356 static void c_stop(struct seq_file *m, void *v)
357 {
358 cpus_read_unlock();
359 }
360
361 const struct seq_operations cpuinfo_op = {
362 .start = c_start,
363 .next = c_next,
364 .stop = c_stop,
365 .show = show_cpuinfo,
366 };
367
s390_isolate_bp(void)368 int s390_isolate_bp(void)
369 {
370 if (!test_facility(82))
371 return -EOPNOTSUPP;
372 set_thread_flag(TIF_ISOLATE_BP);
373 return 0;
374 }
375 EXPORT_SYMBOL(s390_isolate_bp);
376
s390_isolate_bp_guest(void)377 int s390_isolate_bp_guest(void)
378 {
379 if (!test_facility(82))
380 return -EOPNOTSUPP;
381 set_thread_flag(TIF_ISOLATE_BP_GUEST);
382 return 0;
383 }
384 EXPORT_SYMBOL(s390_isolate_bp_guest);
385