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 pr_fmt(fmt) "cpu: " fmt
8
9#include <linux/stop_machine.h>
10#include <linux/cpufeature.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#include <linux/smp.h>
21#include <asm/text-patching.h>
22#include <asm/machine.h>
23#include <asm/diag.h>
24#include <asm/facility.h>
25#include <asm/elf.h>
26#include <asm/lowcore.h>
27#include <asm/param.h>
28#include <asm/sclp.h>
29#include <asm/smp.h>
30
31unsigned long __read_mostly elf_hwcap;
32char elf_platform[ELF_PLATFORM_SIZE];
33
34struct cpu_info {
35 unsigned int cpu_mhz_dynamic;
36 unsigned int cpu_mhz_static;
37 struct cpuid cpu_id;
38};
39
40static DEFINE_PER_CPU(struct cpu_info, cpu_info);
41static DEFINE_PER_CPU(int, cpu_relax_retry);
42
43static bool machine_has_cpu_mhz;
44
45void __init cpu_detect_mhz_feature(void)
46{
47 if (test_facility(34) && __ecag(ECAG_CPU_ATTRIBUTE, 0) != -1UL)
48 machine_has_cpu_mhz = true;
49}
50
51static void update_cpu_mhz(void *arg)
52{
53 unsigned long mhz;
54 struct cpu_info *c;
55
56 mhz = __ecag(ECAG_CPU_ATTRIBUTE, 0);
57 c = this_cpu_ptr(&cpu_info);
58 c->cpu_mhz_dynamic = mhz >> 32;
59 c->cpu_mhz_static = mhz & 0xffffffff;
60}
61
62void s390_update_cpu_mhz(void)
63{
64 s390_adjust_jiffies();
65 if (machine_has_cpu_mhz)
66 on_each_cpu(func: update_cpu_mhz, NULL, wait: 0);
67}
68
69void notrace stop_machine_yield(const struct cpumask *cpumask)
70{
71 int cpu, this_cpu;
72
73 this_cpu = smp_processor_id();
74 if (__this_cpu_inc_return(cpu_relax_retry) >= spin_retry) {
75 __this_cpu_write(cpu_relax_retry, 0);
76 cpu = cpumask_next_wrap(n: this_cpu, src: cpumask);
77 if (cpu >= nr_cpu_ids)
78 return;
79 if (arch_vcpu_is_preempted(cpu))
80 smp_yield_cpu(cpu);
81 }
82}
83
84static void do_sync_core(void *info)
85{
86 sync_core();
87}
88
89void text_poke_sync(void)
90{
91 on_each_cpu(func: do_sync_core, NULL, wait: 1);
92}
93
94void text_poke_sync_lock(void)
95{
96 cpus_read_lock();
97 text_poke_sync();
98 cpus_read_unlock();
99}
100
101/*
102 * cpu_init - initializes state that is per-CPU.
103 */
104void cpu_init(void)
105{
106 struct cpuid *id = this_cpu_ptr(&cpu_info.cpu_id);
107
108 get_cpu_id(id);
109 if (machine_has_cpu_mhz)
110 update_cpu_mhz(NULL);
111 mmgrab(mm: &init_mm);
112 current->active_mm = &init_mm;
113 BUG_ON(current->mm);
114 enter_lazy_tlb(&init_mm, current);
115}
116
117static void show_facilities(struct seq_file *m)
118{
119 unsigned int bit;
120
121 seq_puts(m, s: "facilities :");
122 for_each_set_bit_inv(bit, (long *)&stfle_fac_list, MAX_FACILITY_BIT)
123 seq_printf(m, " %d", bit);
124 seq_putc(m, c: '\n');
125}
126
127static void show_cpu_summary(struct seq_file *m, void *v)
128{
129 static const char *hwcap_str[] = {
130 [HWCAP_NR_ESAN3] = "esan3",
131 [HWCAP_NR_ZARCH] = "zarch",
132 [HWCAP_NR_STFLE] = "stfle",
133 [HWCAP_NR_MSA] = "msa",
134 [HWCAP_NR_LDISP] = "ldisp",
135 [HWCAP_NR_EIMM] = "eimm",
136 [HWCAP_NR_DFP] = "dfp",
137 [HWCAP_NR_HPAGE] = "edat",
138 [HWCAP_NR_ETF3EH] = "etf3eh",
139 [HWCAP_NR_HIGH_GPRS] = "highgprs",
140 [HWCAP_NR_TE] = "te",
141 [HWCAP_NR_VXRS] = "vx",
142 [HWCAP_NR_VXRS_BCD] = "vxd",
143 [HWCAP_NR_VXRS_EXT] = "vxe",
144 [HWCAP_NR_GS] = "gs",
145 [HWCAP_NR_VXRS_EXT2] = "vxe2",
146 [HWCAP_NR_VXRS_PDE] = "vxp",
147 [HWCAP_NR_SORT] = "sort",
148 [HWCAP_NR_DFLT] = "dflt",
149 [HWCAP_NR_VXRS_PDE2] = "vxp2",
150 [HWCAP_NR_NNPA] = "nnpa",
151 [HWCAP_NR_PCI_MIO] = "pcimio",
152 [HWCAP_NR_SIE] = "sie",
153 };
154 int i, cpu;
155
156 BUILD_BUG_ON(ARRAY_SIZE(hwcap_str) != HWCAP_NR_MAX);
157 seq_printf(m, fmt: "vendor_id : IBM/S390\n"
158 "# processors : %i\n"
159 "bogomips per cpu: %lu.%02lu\n",
160 num_online_cpus(), loops_per_jiffy/(500000/HZ),
161 (loops_per_jiffy/(5000/HZ))%100);
162 seq_printf(m, fmt: "max thread id : %d\n", smp_cpu_mtid);
163 seq_puts(m, s: "features\t: ");
164 for (i = 0; i < ARRAY_SIZE(hwcap_str); i++)
165 if (hwcap_str[i] && (elf_hwcap & (1UL << i)))
166 seq_printf(m, "%s ", hwcap_str[i]);
167 seq_puts(m, s: "\n");
168 show_facilities(m);
169 show_cacheinfo(m);
170 for_each_online_cpu(cpu) {
171 struct cpuid *id = &per_cpu(cpu_info.cpu_id, cpu);
172
173 seq_printf(m, fmt: "processor %d: "
174 "version = %02X, "
175 "identification = %06X, "
176 "machine = %04X\n",
177 cpu, id->version, id->ident, id->machine);
178 }
179}
180
181static int __init setup_hwcaps(void)
182{
183 /* instructions named N3, "backported" to esa-mode */
184 elf_hwcap |= HWCAP_ESAN3;
185
186 /* z/Architecture mode active */
187 elf_hwcap |= HWCAP_ZARCH;
188
189 /* store-facility-list-extended */
190 if (test_facility(7))
191 elf_hwcap |= HWCAP_STFLE;
192
193 /* message-security assist */
194 if (test_facility(17))
195 elf_hwcap |= HWCAP_MSA;
196
197 /* long-displacement */
198 if (test_facility(19))
199 elf_hwcap |= HWCAP_LDISP;
200
201 /* extended-immediate */
202 elf_hwcap |= HWCAP_EIMM;
203
204 /* extended-translation facility 3 enhancement */
205 if (test_facility(22) && test_facility(30))
206 elf_hwcap |= HWCAP_ETF3EH;
207
208 /* decimal floating point & perform floating point operation */
209 if (test_facility(42) && test_facility(44))
210 elf_hwcap |= HWCAP_DFP;
211
212 /* huge page support */
213 if (cpu_has_edat1())
214 elf_hwcap |= HWCAP_HPAGE;
215
216 /* 64-bit register support for 31-bit processes */
217 elf_hwcap |= HWCAP_HIGH_GPRS;
218
219 /* transactional execution */
220 if (machine_has_tx())
221 elf_hwcap |= HWCAP_TE;
222
223 /* vector */
224 if (test_facility(129)) {
225 elf_hwcap |= HWCAP_VXRS;
226 if (test_facility(134))
227 elf_hwcap |= HWCAP_VXRS_BCD;
228 if (test_facility(135))
229 elf_hwcap |= HWCAP_VXRS_EXT;
230 if (test_facility(148))
231 elf_hwcap |= HWCAP_VXRS_EXT2;
232 if (test_facility(152))
233 elf_hwcap |= HWCAP_VXRS_PDE;
234 if (test_facility(192))
235 elf_hwcap |= HWCAP_VXRS_PDE2;
236 }
237
238 if (test_facility(150))
239 elf_hwcap |= HWCAP_SORT;
240
241 if (test_facility(151))
242 elf_hwcap |= HWCAP_DFLT;
243
244 if (test_facility(165))
245 elf_hwcap |= HWCAP_NNPA;
246
247 /* guarded storage */
248 if (cpu_has_gs())
249 elf_hwcap |= HWCAP_GS;
250
251 if (test_machine_feature(MFEATURE_PCI_MIO))
252 elf_hwcap |= HWCAP_PCI_MIO;
253
254 /* virtualization support */
255 if (sclp.has_sief2)
256 elf_hwcap |= HWCAP_SIE;
257
258 return 0;
259}
260arch_initcall(setup_hwcaps);
261
262static int __init setup_elf_platform(void)
263{
264 struct cpuid cpu_id;
265
266 get_cpu_id(&cpu_id);
267 add_device_randomness(buf: &cpu_id, len: sizeof(cpu_id));
268 switch (cpu_id.machine) {
269 default: /* Use "z10" as default. */
270 strscpy(elf_platform, "z10");
271 break;
272 case 0x2817:
273 case 0x2818:
274 strscpy(elf_platform, "z196");
275 break;
276 case 0x2827:
277 case 0x2828:
278 strscpy(elf_platform, "zEC12");
279 break;
280 case 0x2964:
281 case 0x2965:
282 strscpy(elf_platform, "z13");
283 break;
284 case 0x3906:
285 case 0x3907:
286 strscpy(elf_platform, "z14");
287 break;
288 case 0x8561:
289 case 0x8562:
290 strscpy(elf_platform, "z15");
291 break;
292 case 0x3931:
293 case 0x3932:
294 strscpy(elf_platform, "z16");
295 break;
296 case 0x9175:
297 case 0x9176:
298 strscpy(elf_platform, "z17");
299 break;
300 }
301 return 0;
302}
303arch_initcall(setup_elf_platform);
304
305static void show_cpu_topology(struct seq_file *m, unsigned long n)
306{
307#ifdef CONFIG_SCHED_TOPOLOGY
308 seq_printf(m, "physical id : %d\n", topology_physical_package_id(n));
309 seq_printf(m, "core id : %d\n", topology_core_id(n));
310 seq_printf(m, "book id : %d\n", topology_book_id(n));
311 seq_printf(m, "drawer id : %d\n", topology_drawer_id(n));
312 seq_printf(m, "dedicated : %d\n", topology_cpu_dedicated(n));
313 seq_printf(m, "address : %d\n", smp_cpu_get_cpu_address(n));
314 seq_printf(m, "siblings : %d\n", cpumask_weight(topology_core_cpumask(n)));
315 seq_printf(m, "cpu cores : %d\n", topology_booted_cores(n));
316#endif /* CONFIG_SCHED_TOPOLOGY */
317}
318
319static void show_cpu_ids(struct seq_file *m, unsigned long n)
320{
321 struct cpuid *id = &per_cpu(cpu_info.cpu_id, n);
322
323 seq_printf(m, fmt: "version : %02X\n", id->version);
324 seq_printf(m, fmt: "identification : %06X\n", id->ident);
325 seq_printf(m, fmt: "machine : %04X\n", id->machine);
326}
327
328static void show_cpu_mhz(struct seq_file *m, unsigned long n)
329{
330 struct cpu_info *c = per_cpu_ptr(&cpu_info, n);
331
332 if (!machine_has_cpu_mhz)
333 return;
334 seq_printf(m, fmt: "cpu MHz dynamic : %d\n", c->cpu_mhz_dynamic);
335 seq_printf(m, fmt: "cpu MHz static : %d\n", c->cpu_mhz_static);
336}
337
338/*
339 * show_cpuinfo - Get information on one CPU for use by procfs.
340 */
341static int show_cpuinfo(struct seq_file *m, void *v)
342{
343 unsigned long n = (unsigned long) v - 1;
344 unsigned long first = cpumask_first(cpu_online_mask);
345
346 if (n == first)
347 show_cpu_summary(m, v);
348 seq_printf(m, fmt: "\ncpu number : %ld\n", n);
349 show_cpu_topology(m, n);
350 show_cpu_ids(m, n);
351 show_cpu_mhz(m, n);
352 return 0;
353}
354
355static inline void *c_update(loff_t *pos)
356{
357 if (*pos)
358 *pos = cpumask_next(n: *pos - 1, cpu_online_mask);
359 else
360 *pos = cpumask_first(cpu_online_mask);
361 return *pos < nr_cpu_ids ? (void *)*pos + 1 : NULL;
362}
363
364static void *c_start(struct seq_file *m, loff_t *pos)
365{
366 cpus_read_lock();
367 return c_update(pos);
368}
369
370static void *c_next(struct seq_file *m, void *v, loff_t *pos)
371{
372 ++*pos;
373 return c_update(pos);
374}
375
376static void c_stop(struct seq_file *m, void *v)
377{
378 cpus_read_unlock();
379}
380
381const struct seq_operations cpuinfo_op = {
382 .start = c_start,
383 .next = c_next,
384 .stop = c_stop,
385 .show = show_cpuinfo,
386};
387

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