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/cpufeature.h>
12 #include <linux/bitops.h>
13 #include <linux/kernel.h>
14 #include <linux/random.h>
15 #include <linux/sched/mm.h>
16 #include <linux/init.h>
17 #include <linux/seq_file.h>
18 #include <linux/mm_types.h>
19 #include <linux/delay.h>
20 #include <linux/cpu.h>
21
22 #include <asm/diag.h>
23 #include <asm/facility.h>
24 #include <asm/elf.h>
25 #include <asm/lowcore.h>
26 #include <asm/param.h>
27 #include <asm/sclp.h>
28 #include <asm/smp.h>
29
30 unsigned long __read_mostly elf_hwcap;
31 char elf_platform[ELF_PLATFORM_SIZE];
32
33 struct cpu_info {
34 unsigned int cpu_mhz_dynamic;
35 unsigned int cpu_mhz_static;
36 struct cpuid cpu_id;
37 };
38
39 static DEFINE_PER_CPU(struct cpu_info, cpu_info);
40 static DEFINE_PER_CPU(int, cpu_relax_retry);
41
42 static bool machine_has_cpu_mhz;
43
cpu_detect_mhz_feature(void)44 void __init cpu_detect_mhz_feature(void)
45 {
46 if (test_facility(34) && __ecag(ECAG_CPU_ATTRIBUTE, 0) != -1UL)
47 machine_has_cpu_mhz = true;
48 }
49
update_cpu_mhz(void * arg)50 static void update_cpu_mhz(void *arg)
51 {
52 unsigned long mhz;
53 struct cpu_info *c;
54
55 mhz = __ecag(ECAG_CPU_ATTRIBUTE, 0);
56 c = this_cpu_ptr(&cpu_info);
57 c->cpu_mhz_dynamic = mhz >> 32;
58 c->cpu_mhz_static = mhz & 0xffffffff;
59 }
60
s390_update_cpu_mhz(void)61 void s390_update_cpu_mhz(void)
62 {
63 s390_adjust_jiffies();
64 if (machine_has_cpu_mhz)
65 on_each_cpu(update_cpu_mhz, NULL, 0);
66 }
67
stop_machine_yield(const struct cpumask * cpumask)68 void notrace stop_machine_yield(const struct cpumask *cpumask)
69 {
70 int cpu, this_cpu;
71
72 this_cpu = smp_processor_id();
73 if (__this_cpu_inc_return(cpu_relax_retry) >= spin_retry) {
74 __this_cpu_write(cpu_relax_retry, 0);
75 cpu = cpumask_next_wrap(this_cpu, cpumask, this_cpu, false);
76 if (cpu >= nr_cpu_ids)
77 return;
78 if (arch_vcpu_is_preempted(cpu))
79 smp_yield_cpu(cpu);
80 }
81 }
82
83 /*
84 * cpu_init - initializes state that is per-CPU.
85 */
cpu_init(void)86 void cpu_init(void)
87 {
88 struct cpuid *id = this_cpu_ptr(&cpu_info.cpu_id);
89
90 get_cpu_id(id);
91 if (machine_has_cpu_mhz)
92 update_cpu_mhz(NULL);
93 mmgrab(&init_mm);
94 current->active_mm = &init_mm;
95 BUG_ON(current->mm);
96 enter_lazy_tlb(&init_mm, current);
97 }
98
99 /*
100 * cpu_have_feature - Test CPU features on module initialization
101 */
cpu_have_feature(unsigned int num)102 int cpu_have_feature(unsigned int num)
103 {
104 return elf_hwcap & (1UL << num);
105 }
106 EXPORT_SYMBOL(cpu_have_feature);
107
show_facilities(struct seq_file * m)108 static void show_facilities(struct seq_file *m)
109 {
110 unsigned int bit;
111
112 seq_puts(m, "facilities :");
113 for_each_set_bit_inv(bit, (long *)&stfle_fac_list, MAX_FACILITY_BIT)
114 seq_printf(m, " %d", bit);
115 seq_putc(m, '\n');
116 }
117
show_cpu_summary(struct seq_file * m,void * v)118 static void show_cpu_summary(struct seq_file *m, void *v)
119 {
120 static const char *hwcap_str[] = {
121 [HWCAP_NR_ESAN3] = "esan3",
122 [HWCAP_NR_ZARCH] = "zarch",
123 [HWCAP_NR_STFLE] = "stfle",
124 [HWCAP_NR_MSA] = "msa",
125 [HWCAP_NR_LDISP] = "ldisp",
126 [HWCAP_NR_EIMM] = "eimm",
127 [HWCAP_NR_DFP] = "dfp",
128 [HWCAP_NR_HPAGE] = "edat",
129 [HWCAP_NR_ETF3EH] = "etf3eh",
130 [HWCAP_NR_HIGH_GPRS] = "highgprs",
131 [HWCAP_NR_TE] = "te",
132 [HWCAP_NR_VXRS] = "vx",
133 [HWCAP_NR_VXRS_BCD] = "vxd",
134 [HWCAP_NR_VXRS_EXT] = "vxe",
135 [HWCAP_NR_GS] = "gs",
136 [HWCAP_NR_VXRS_EXT2] = "vxe2",
137 [HWCAP_NR_VXRS_PDE] = "vxp",
138 [HWCAP_NR_SORT] = "sort",
139 [HWCAP_NR_DFLT] = "dflt",
140 [HWCAP_NR_VXRS_PDE2] = "vxp2",
141 [HWCAP_NR_NNPA] = "nnpa",
142 [HWCAP_NR_PCI_MIO] = "pcimio",
143 [HWCAP_NR_SIE] = "sie",
144 };
145 int i, cpu;
146
147 BUILD_BUG_ON(ARRAY_SIZE(hwcap_str) != HWCAP_NR_MAX);
148 seq_printf(m, "vendor_id : IBM/S390\n"
149 "# processors : %i\n"
150 "bogomips per cpu: %lu.%02lu\n",
151 num_online_cpus(), loops_per_jiffy/(500000/HZ),
152 (loops_per_jiffy/(5000/HZ))%100);
153 seq_printf(m, "max thread id : %d\n", smp_cpu_mtid);
154 seq_puts(m, "features\t: ");
155 for (i = 0; i < ARRAY_SIZE(hwcap_str); i++)
156 if (hwcap_str[i] && (elf_hwcap & (1UL << i)))
157 seq_printf(m, "%s ", hwcap_str[i]);
158 seq_puts(m, "\n");
159 show_facilities(m);
160 show_cacheinfo(m);
161 for_each_online_cpu(cpu) {
162 struct cpuid *id = &per_cpu(cpu_info.cpu_id, cpu);
163
164 seq_printf(m, "processor %d: "
165 "version = %02X, "
166 "identification = %06X, "
167 "machine = %04X\n",
168 cpu, id->version, id->ident, id->machine);
169 }
170 }
171
setup_hwcaps(void)172 static int __init setup_hwcaps(void)
173 {
174 /* instructions named N3, "backported" to esa-mode */
175 if (test_facility(0))
176 elf_hwcap |= HWCAP_ESAN3;
177
178 /* z/Architecture mode active */
179 elf_hwcap |= HWCAP_ZARCH;
180
181 /* store-facility-list-extended */
182 if (test_facility(7))
183 elf_hwcap |= HWCAP_STFLE;
184
185 /* message-security assist */
186 if (test_facility(17))
187 elf_hwcap |= HWCAP_MSA;
188
189 /* long-displacement */
190 if (test_facility(19))
191 elf_hwcap |= HWCAP_LDISP;
192
193 /* extended-immediate */
194 if (test_facility(21))
195 elf_hwcap |= HWCAP_EIMM;
196
197 /* extended-translation facility 3 enhancement */
198 if (test_facility(22) && test_facility(30))
199 elf_hwcap |= HWCAP_ETF3EH;
200
201 /* decimal floating point & perform floating point operation */
202 if (test_facility(42) && test_facility(44))
203 elf_hwcap |= HWCAP_DFP;
204
205 /* huge page support */
206 if (MACHINE_HAS_EDAT1)
207 elf_hwcap |= HWCAP_HPAGE;
208
209 /* 64-bit register support for 31-bit processes */
210 elf_hwcap |= HWCAP_HIGH_GPRS;
211
212 /* transactional execution */
213 if (MACHINE_HAS_TE)
214 elf_hwcap |= HWCAP_TE;
215
216 /*
217 * Vector extension can be disabled with the "novx" parameter.
218 * Use MACHINE_HAS_VX instead of facility bit 129.
219 */
220 if (MACHINE_HAS_VX) {
221 elf_hwcap |= HWCAP_VXRS;
222 if (test_facility(134))
223 elf_hwcap |= HWCAP_VXRS_BCD;
224 if (test_facility(135))
225 elf_hwcap |= HWCAP_VXRS_EXT;
226 if (test_facility(148))
227 elf_hwcap |= HWCAP_VXRS_EXT2;
228 if (test_facility(152))
229 elf_hwcap |= HWCAP_VXRS_PDE;
230 if (test_facility(192))
231 elf_hwcap |= HWCAP_VXRS_PDE2;
232 }
233
234 if (test_facility(150))
235 elf_hwcap |= HWCAP_SORT;
236
237 if (test_facility(151))
238 elf_hwcap |= HWCAP_DFLT;
239
240 if (test_facility(165))
241 elf_hwcap |= HWCAP_NNPA;
242
243 /* guarded storage */
244 if (MACHINE_HAS_GS)
245 elf_hwcap |= HWCAP_GS;
246
247 if (MACHINE_HAS_PCI_MIO)
248 elf_hwcap |= HWCAP_PCI_MIO;
249
250 /* virtualization support */
251 if (sclp.has_sief2)
252 elf_hwcap |= HWCAP_SIE;
253
254 return 0;
255 }
256 arch_initcall(setup_hwcaps);
257
setup_elf_platform(void)258 static int __init setup_elf_platform(void)
259 {
260 struct cpuid cpu_id;
261
262 get_cpu_id(&cpu_id);
263 add_device_randomness(&cpu_id, sizeof(cpu_id));
264 switch (cpu_id.machine) {
265 case 0x2064:
266 case 0x2066:
267 default: /* Use "z900" as default for 64 bit kernels. */
268 strcpy(elf_platform, "z900");
269 break;
270 case 0x2084:
271 case 0x2086:
272 strcpy(elf_platform, "z990");
273 break;
274 case 0x2094:
275 case 0x2096:
276 strcpy(elf_platform, "z9-109");
277 break;
278 case 0x2097:
279 case 0x2098:
280 strcpy(elf_platform, "z10");
281 break;
282 case 0x2817:
283 case 0x2818:
284 strcpy(elf_platform, "z196");
285 break;
286 case 0x2827:
287 case 0x2828:
288 strcpy(elf_platform, "zEC12");
289 break;
290 case 0x2964:
291 case 0x2965:
292 strcpy(elf_platform, "z13");
293 break;
294 case 0x3906:
295 case 0x3907:
296 strcpy(elf_platform, "z14");
297 break;
298 case 0x8561:
299 case 0x8562:
300 strcpy(elf_platform, "z15");
301 break;
302 }
303 return 0;
304 }
305 arch_initcall(setup_elf_platform);
306
show_cpu_topology(struct seq_file * m,unsigned long n)307 static void show_cpu_topology(struct seq_file *m, unsigned long n)
308 {
309 #ifdef CONFIG_SCHED_TOPOLOGY
310 seq_printf(m, "physical id : %d\n", topology_physical_package_id(n));
311 seq_printf(m, "core id : %d\n", topology_core_id(n));
312 seq_printf(m, "book id : %d\n", topology_book_id(n));
313 seq_printf(m, "drawer id : %d\n", topology_drawer_id(n));
314 seq_printf(m, "dedicated : %d\n", topology_cpu_dedicated(n));
315 seq_printf(m, "address : %d\n", smp_cpu_get_cpu_address(n));
316 seq_printf(m, "siblings : %d\n", cpumask_weight(topology_core_cpumask(n)));
317 seq_printf(m, "cpu cores : %d\n", topology_booted_cores(n));
318 #endif /* CONFIG_SCHED_TOPOLOGY */
319 }
320
show_cpu_ids(struct seq_file * m,unsigned long n)321 static void show_cpu_ids(struct seq_file *m, unsigned long n)
322 {
323 struct cpuid *id = &per_cpu(cpu_info.cpu_id, n);
324
325 seq_printf(m, "version : %02X\n", id->version);
326 seq_printf(m, "identification : %06X\n", id->ident);
327 seq_printf(m, "machine : %04X\n", id->machine);
328 }
329
show_cpu_mhz(struct seq_file * m,unsigned long n)330 static void show_cpu_mhz(struct seq_file *m, unsigned long n)
331 {
332 struct cpu_info *c = per_cpu_ptr(&cpu_info, n);
333
334 if (!machine_has_cpu_mhz)
335 return;
336 seq_printf(m, "cpu MHz dynamic : %d\n", c->cpu_mhz_dynamic);
337 seq_printf(m, "cpu MHz static : %d\n", c->cpu_mhz_static);
338 }
339
340 /*
341 * show_cpuinfo - Get information on one CPU for use by procfs.
342 */
show_cpuinfo(struct seq_file * m,void * v)343 static int show_cpuinfo(struct seq_file *m, void *v)
344 {
345 unsigned long n = (unsigned long) v - 1;
346 unsigned long first = cpumask_first(cpu_online_mask);
347
348 if (n == first)
349 show_cpu_summary(m, v);
350 seq_printf(m, "\ncpu number : %ld\n", n);
351 show_cpu_topology(m, n);
352 show_cpu_ids(m, n);
353 show_cpu_mhz(m, n);
354 return 0;
355 }
356
c_update(loff_t * pos)357 static inline void *c_update(loff_t *pos)
358 {
359 if (*pos)
360 *pos = cpumask_next(*pos - 1, cpu_online_mask);
361 else
362 *pos = cpumask_first(cpu_online_mask);
363 return *pos < nr_cpu_ids ? (void *)*pos + 1 : NULL;
364 }
365
c_start(struct seq_file * m,loff_t * pos)366 static void *c_start(struct seq_file *m, loff_t *pos)
367 {
368 cpus_read_lock();
369 return c_update(pos);
370 }
371
c_next(struct seq_file * m,void * v,loff_t * pos)372 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
373 {
374 ++*pos;
375 return c_update(pos);
376 }
377
c_stop(struct seq_file * m,void * v)378 static void c_stop(struct seq_file *m, void *v)
379 {
380 cpus_read_unlock();
381 }
382
383 const struct seq_operations cpuinfo_op = {
384 .start = c_start,
385 .next = c_next,
386 .stop = c_stop,
387 .show = show_cpuinfo,
388 };
389
s390_isolate_bp(void)390 int s390_isolate_bp(void)
391 {
392 if (!test_facility(82))
393 return -EOPNOTSUPP;
394 set_thread_flag(TIF_ISOLATE_BP);
395 return 0;
396 }
397 EXPORT_SYMBOL(s390_isolate_bp);
398
s390_isolate_bp_guest(void)399 int s390_isolate_bp_guest(void)
400 {
401 if (!test_facility(82))
402 return -EOPNOTSUPP;
403 set_thread_flag(TIF_ISOLATE_BP_GUEST);
404 return 0;
405 }
406 EXPORT_SYMBOL(s390_isolate_bp_guest);
407