s390/kernel/processor.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  *  Copyright IBM Corp. 2008
0004  *  Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
0005  */
0006
0007 #define KMSG_COMPONENT "cpu"
0008 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
0009
0010 #include <linux/stop_machine.h>
0011 #include <linux/bitops.h>
0012 #include <linux/kernel.h>
0013 #include <linux/random.h>
0014 #include <linux/sched/mm.h>
0015 #include <linux/init.h>
0016 #include <linux/seq_file.h>
0017 #include <linux/mm_types.h>
0018 #include <linux/delay.h>
0019 #include <linux/cpu.h>
0020
0021 #include <asm/diag.h>
0022 #include <asm/facility.h>
0023 #include <asm/elf.h>
0024 #include <asm/lowcore.h>
0025 #include <asm/param.h>
0026 #include <asm/sclp.h>
0027 #include <asm/smp.h>
0028
0029 unsigned long __read_mostly elf_hwcap;
0030 char elf_platform[ELF_PLATFORM_SIZE];
0031
0032 struct cpu_info {
0033     unsigned int cpu_mhz_dynamic;
0034     unsigned int cpu_mhz_static;
0035     struct cpuid cpu_id;
0036 };
0037
0038 static DEFINE_PER_CPU(struct cpu_info, cpu_info);
0039 static DEFINE_PER_CPU(int, cpu_relax_retry);
0040
0041 static bool machine_has_cpu_mhz;
0042
0043 void __init cpu_detect_mhz_feature(void)
0044 {
0045     if (test_facility(34) && __ecag(ECAG_CPU_ATTRIBUTE, 0) != -1UL)
0046         machine_has_cpu_mhz = true;
0047 }
0048
0049 static void update_cpu_mhz(void *arg)
0050 {
0051     unsigned long mhz;
0052     struct cpu_info *c;
0053
0054     mhz = __ecag(ECAG_CPU_ATTRIBUTE, 0);
0055     c = this_cpu_ptr(&cpu_info);
0056     c->cpu_mhz_dynamic = mhz >> 32;
0057     c->cpu_mhz_static = mhz & 0xffffffff;
0058 }
0059
0060 void s390_update_cpu_mhz(void)
0061 {
0062     s390_adjust_jiffies();
0063     if (machine_has_cpu_mhz)
0064         on_each_cpu(update_cpu_mhz, NULL, 0);
0065 }
0066
0067 void notrace stop_machine_yield(const struct cpumask *cpumask)
0068 {
0069     int cpu, this_cpu;
0070
0071     this_cpu = smp_processor_id();
0072     if (__this_cpu_inc_return(cpu_relax_retry) >= spin_retry) {
0073         __this_cpu_write(cpu_relax_retry, 0);
0074         cpu = cpumask_next_wrap(this_cpu, cpumask, this_cpu, false);
0075         if (cpu >= nr_cpu_ids)
0076             return;
0077         if (arch_vcpu_is_preempted(cpu))
0078             smp_yield_cpu(cpu);
0079     }
0080 }
0081
0082 /*
0083  * cpu_init - initializes state that is per-CPU.
0084  */
0085 void cpu_init(void)
0086 {
0087     struct cpuid *id = this_cpu_ptr(&cpu_info.cpu_id);
0088
0089     get_cpu_id(id);
0090     if (machine_has_cpu_mhz)
0091         update_cpu_mhz(NULL);
0092     mmgrab(&init_mm);
0093     current->active_mm = &init_mm;
0094     BUG_ON(current->mm);
0095     enter_lazy_tlb(&init_mm, current);
0096 }
0097
0098 static void show_facilities(struct seq_file *m)
0099 {
0100     unsigned int bit;
0101
0102     seq_puts(m, "facilities      :");
0103     for_each_set_bit_inv(bit, (long *)&stfle_fac_list, MAX_FACILITY_BIT)
0104         seq_printf(m, " %d", bit);
0105     seq_putc(m, '\n');
0106 }
0107
0108 static void show_cpu_summary(struct seq_file *m, void *v)
0109 {
0110     static const char *hwcap_str[] = {
0111         [HWCAP_NR_ESAN3]    = "esan3",
0112         [HWCAP_NR_ZARCH]    = "zarch",
0113         [HWCAP_NR_STFLE]    = "stfle",
0114         [HWCAP_NR_MSA]      = "msa",
0115         [HWCAP_NR_LDISP]    = "ldisp",
0116         [HWCAP_NR_EIMM]     = "eimm",
0117         [HWCAP_NR_DFP]      = "dfp",
0118         [HWCAP_NR_HPAGE]    = "edat",
0119         [HWCAP_NR_ETF3EH]   = "etf3eh",
0120         [HWCAP_NR_HIGH_GPRS]    = "highgprs",
0121         [HWCAP_NR_TE]       = "te",
0122         [HWCAP_NR_VXRS]     = "vx",
0123         [HWCAP_NR_VXRS_BCD] = "vxd",
0124         [HWCAP_NR_VXRS_EXT] = "vxe",
0125         [HWCAP_NR_GS]       = "gs",
0126         [HWCAP_NR_VXRS_EXT2]    = "vxe2",
0127         [HWCAP_NR_VXRS_PDE] = "vxp",
0128         [HWCAP_NR_SORT]     = "sort",
0129         [HWCAP_NR_DFLT]     = "dflt",
0130         [HWCAP_NR_VXRS_PDE2]    = "vxp2",
0131         [HWCAP_NR_NNPA]     = "nnpa",
0132         [HWCAP_NR_PCI_MIO]  = "pcimio",
0133         [HWCAP_NR_SIE]      = "sie",
0134     };
0135     int i, cpu;
0136
0137     BUILD_BUG_ON(ARRAY_SIZE(hwcap_str) != HWCAP_NR_MAX);
0138     seq_printf(m, "vendor_id       : IBM/S390\n"
0139            "# processors    : %i\n"
0140            "bogomips per cpu: %lu.%02lu\n",
0141            num_online_cpus(), loops_per_jiffy/(500000/HZ),
0142            (loops_per_jiffy/(5000/HZ))%100);
0143     seq_printf(m, "max thread id   : %d\n", smp_cpu_mtid);
0144     seq_puts(m, "features\t: ");
0145     for (i = 0; i < ARRAY_SIZE(hwcap_str); i++)
0146         if (hwcap_str[i] && (elf_hwcap & (1UL << i)))
0147             seq_printf(m, "%s ", hwcap_str[i]);
0148     seq_puts(m, "\n");
0149     show_facilities(m);
0150     show_cacheinfo(m);
0151     for_each_online_cpu(cpu) {
0152         struct cpuid *id = &per_cpu(cpu_info.cpu_id, cpu);
0153
0154         seq_printf(m, "processor %d: "
0155                "version = %02X,  "
0156                "identification = %06X,  "
0157                "machine = %04X\n",
0158                cpu, id->version, id->ident, id->machine);
0159     }
0160 }
0161
0162 static int __init setup_hwcaps(void)
0163 {
0164     /* instructions named N3, "backported" to esa-mode */
0165     elf_hwcap |= HWCAP_ESAN3;
0166
0167     /* z/Architecture mode active */
0168     elf_hwcap |= HWCAP_ZARCH;
0169
0170     /* store-facility-list-extended */
0171     if (test_facility(7))
0172         elf_hwcap |= HWCAP_STFLE;
0173
0174     /* message-security assist */
0175     if (test_facility(17))
0176         elf_hwcap |= HWCAP_MSA;
0177
0178     /* long-displacement */
0179     if (test_facility(19))
0180         elf_hwcap |= HWCAP_LDISP;
0181
0182     /* extended-immediate */
0183     elf_hwcap |= HWCAP_EIMM;
0184
0185     /* extended-translation facility 3 enhancement */
0186     if (test_facility(22) && test_facility(30))
0187         elf_hwcap |= HWCAP_ETF3EH;
0188
0189     /* decimal floating point & perform floating point operation */
0190     if (test_facility(42) && test_facility(44))
0191         elf_hwcap |= HWCAP_DFP;
0192
0193     /* huge page support */
0194     if (MACHINE_HAS_EDAT1)
0195         elf_hwcap |= HWCAP_HPAGE;
0196
0197     /* 64-bit register support for 31-bit processes */
0198     elf_hwcap |= HWCAP_HIGH_GPRS;
0199
0200     /* transactional execution */
0201     if (MACHINE_HAS_TE)
0202         elf_hwcap |= HWCAP_TE;
0203
0204     /*
0205      * Vector extension can be disabled with the "novx" parameter.
0206      * Use MACHINE_HAS_VX instead of facility bit 129.
0207      */
0208     if (MACHINE_HAS_VX) {
0209         elf_hwcap |= HWCAP_VXRS;
0210         if (test_facility(134))
0211             elf_hwcap |= HWCAP_VXRS_BCD;
0212         if (test_facility(135))
0213             elf_hwcap |= HWCAP_VXRS_EXT;
0214         if (test_facility(148))
0215             elf_hwcap |= HWCAP_VXRS_EXT2;
0216         if (test_facility(152))
0217             elf_hwcap |= HWCAP_VXRS_PDE;
0218         if (test_facility(192))
0219             elf_hwcap |= HWCAP_VXRS_PDE2;
0220     }
0221
0222     if (test_facility(150))
0223         elf_hwcap |= HWCAP_SORT;
0224
0225     if (test_facility(151))
0226         elf_hwcap |= HWCAP_DFLT;
0227
0228     if (test_facility(165))
0229         elf_hwcap |= HWCAP_NNPA;
0230
0231     /* guarded storage */
0232     if (MACHINE_HAS_GS)
0233         elf_hwcap |= HWCAP_GS;
0234
0235     if (MACHINE_HAS_PCI_MIO)
0236         elf_hwcap |= HWCAP_PCI_MIO;
0237
0238     /* virtualization support */
0239     if (sclp.has_sief2)
0240         elf_hwcap |= HWCAP_SIE;
0241
0242     return 0;
0243 }
0244 arch_initcall(setup_hwcaps);
0245
0246 static int __init setup_elf_platform(void)
0247 {
0248     struct cpuid cpu_id;
0249
0250     get_cpu_id(&cpu_id);
0251     add_device_randomness(&cpu_id, sizeof(cpu_id));
0252     switch (cpu_id.machine) {
0253     default:    /* Use "z10" as default. */
0254         strcpy(elf_platform, "z10");
0255         break;
0256     case 0x2817:
0257     case 0x2818:
0258         strcpy(elf_platform, "z196");
0259         break;
0260     case 0x2827:
0261     case 0x2828:
0262         strcpy(elf_platform, "zEC12");
0263         break;
0264     case 0x2964:
0265     case 0x2965:
0266         strcpy(elf_platform, "z13");
0267         break;
0268     case 0x3906:
0269     case 0x3907:
0270         strcpy(elf_platform, "z14");
0271         break;
0272     case 0x8561:
0273     case 0x8562:
0274         strcpy(elf_platform, "z15");
0275         break;
0276     case 0x3931:
0277     case 0x3932:
0278         strcpy(elf_platform, "z16");
0279         break;
0280     }
0281     return 0;
0282 }
0283 arch_initcall(setup_elf_platform);
0284
0285 static void show_cpu_topology(struct seq_file *m, unsigned long n)
0286 {
0287 #ifdef CONFIG_SCHED_TOPOLOGY
0288     seq_printf(m, "physical id     : %d\n", topology_physical_package_id(n));
0289     seq_printf(m, "core id         : %d\n", topology_core_id(n));
0290     seq_printf(m, "book id         : %d\n", topology_book_id(n));
0291     seq_printf(m, "drawer id       : %d\n", topology_drawer_id(n));
0292     seq_printf(m, "dedicated       : %d\n", topology_cpu_dedicated(n));
0293     seq_printf(m, "address         : %d\n", smp_cpu_get_cpu_address(n));
0294     seq_printf(m, "siblings        : %d\n", cpumask_weight(topology_core_cpumask(n)));
0295     seq_printf(m, "cpu cores       : %d\n", topology_booted_cores(n));
0296 #endif /* CONFIG_SCHED_TOPOLOGY */
0297 }
0298
0299 static void show_cpu_ids(struct seq_file *m, unsigned long n)
0300 {
0301     struct cpuid *id = &per_cpu(cpu_info.cpu_id, n);
0302
0303     seq_printf(m, "version         : %02X\n", id->version);
0304     seq_printf(m, "identification  : %06X\n", id->ident);
0305     seq_printf(m, "machine         : %04X\n", id->machine);
0306 }
0307
0308 static void show_cpu_mhz(struct seq_file *m, unsigned long n)
0309 {
0310     struct cpu_info *c = per_cpu_ptr(&cpu_info, n);
0311
0312     if (!machine_has_cpu_mhz)
0313         return;
0314     seq_printf(m, "cpu MHz dynamic : %d\n", c->cpu_mhz_dynamic);
0315     seq_printf(m, "cpu MHz static  : %d\n", c->cpu_mhz_static);
0316 }
0317
0318 /*
0319  * show_cpuinfo - Get information on one CPU for use by procfs.
0320  */
0321 static int show_cpuinfo(struct seq_file *m, void *v)
0322 {
0323     unsigned long n = (unsigned long) v - 1;
0324     unsigned long first = cpumask_first(cpu_online_mask);
0325
0326     if (n == first)
0327         show_cpu_summary(m, v);
0328     seq_printf(m, "\ncpu number      : %ld\n", n);
0329     show_cpu_topology(m, n);
0330     show_cpu_ids(m, n);
0331     show_cpu_mhz(m, n);
0332     return 0;
0333 }
0334
0335 static inline void *c_update(loff_t *pos)
0336 {
0337     if (*pos)
0338         *pos = cpumask_next(*pos - 1, cpu_online_mask);
0339     else
0340         *pos = cpumask_first(cpu_online_mask);
0341     return *pos < nr_cpu_ids ? (void *)*pos + 1 : NULL;
0342 }
0343
0344 static void *c_start(struct seq_file *m, loff_t *pos)
0345 {
0346     cpus_read_lock();
0347     return c_update(pos);
0348 }
0349
0350 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
0351 {
0352     ++*pos;
0353     return c_update(pos);
0354 }
0355
0356 static void c_stop(struct seq_file *m, void *v)
0357 {
0358     cpus_read_unlock();
0359 }
0360
0361 const struct seq_operations cpuinfo_op = {
0362     .start  = c_start,
0363     .next   = c_next,
0364     .stop   = c_stop,
0365     .show   = show_cpuinfo,
0366 };
0367
0368 int s390_isolate_bp(void)
0369 {
0370     if (!test_facility(82))
0371         return -EOPNOTSUPP;
0372     set_thread_flag(TIF_ISOLATE_BP);
0373     return 0;
0374 }
0375 EXPORT_SYMBOL(s390_isolate_bp);
0376
0377 int s390_isolate_bp_guest(void)
0378 {
0379     if (!test_facility(82))
0380         return -EOPNOTSUPP;
0381     set_thread_flag(TIF_ISOLATE_BP_GUEST);
0382     return 0;
0383 }
0384 EXPORT_SYMBOL(s390_isolate_bp_guest);