1 files changed, 253 insertions, 0 deletions
diff --git a/arch/s390/kernel/processor.c b/arch/s390/kernel/processor.c
new file mode 100644
index 000000000..c92d04f87
--- /dev/null
+++ b/arch/s390/kernel/processor.c
@@ -0,0 +1,253 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  Copyright IBM Corp. 2008
+ *  Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
+ */
+
+#define KMSG_COMPONENT "cpu"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
+#include <linux/stop_machine.h>
+#include <linux/cpufeature.h>
+#include <linux/bitops.h>
+#include <linux/kernel.h>
+#include <linux/sched/mm.h>
+#include <linux/init.h>
+#include <linux/seq_file.h>
+#include <linux/mm_types.h>
+#include <linux/delay.h>
+#include <linux/cpu.h>
+
+#include <asm/diag.h>
+#include <asm/facility.h>
+#include <asm/elf.h>
+#include <asm/lowcore.h>
+#include <asm/param.h>
+#include <asm/smp.h>
+
+struct cpu_info {
+	unsigned int cpu_mhz_dynamic;
+	unsigned int cpu_mhz_static;
+	struct cpuid cpu_id;
+};
+
+static DEFINE_PER_CPU(struct cpu_info, cpu_info);
+static DEFINE_PER_CPU(int, cpu_relax_retry);
+
+static bool machine_has_cpu_mhz;
+
+void __init cpu_detect_mhz_feature(void)
+{
+	if (test_facility(34) && __ecag(ECAG_CPU_ATTRIBUTE, 0) != -1UL)
+		machine_has_cpu_mhz = true;
+}
+
+static void update_cpu_mhz(void *arg)
+{
+	unsigned long mhz;
+	struct cpu_info *c;
+
+	mhz = __ecag(ECAG_CPU_ATTRIBUTE, 0);
+	c = this_cpu_ptr(&cpu_info);
+	c->cpu_mhz_dynamic = mhz >> 32;
+	c->cpu_mhz_static = mhz & 0xffffffff;
+}
+
+void s390_update_cpu_mhz(void)
+{
+	s390_adjust_jiffies();
+	if (machine_has_cpu_mhz)
+		on_each_cpu(update_cpu_mhz, NULL, 0);
+}
+
+void notrace stop_machine_yield(const struct cpumask *cpumask)
+{
+	int cpu, this_cpu;
+
+	this_cpu = smp_processor_id();
+	if (__this_cpu_inc_return(cpu_relax_retry) >= spin_retry) {
+		__this_cpu_write(cpu_relax_retry, 0);
+		cpu = cpumask_next_wrap(this_cpu, cpumask, this_cpu, false);
+		if (cpu >= nr_cpu_ids)
+			return;
+		if (arch_vcpu_is_preempted(cpu))
+			smp_yield_cpu(cpu);
+	}
+}
+
+/*
+ * cpu_init - initializes state that is per-CPU.
+ */
+void cpu_init(void)
+{
+	struct cpuid *id = this_cpu_ptr(&cpu_info.cpu_id);
+
+	get_cpu_id(id);
+	if (machine_has_cpu_mhz)
+		update_cpu_mhz(NULL);
+	mmgrab(&init_mm);
+	current->active_mm = &init_mm;
+	BUG_ON(current->mm);
+	enter_lazy_tlb(&init_mm, current);
+}
+
+/*
+ * cpu_have_feature - Test CPU features on module initialization
+ */
+int cpu_have_feature(unsigned int num)
+{
+	return elf_hwcap & (1UL << num);
+}
+EXPORT_SYMBOL(cpu_have_feature);
+
+static void show_facilities(struct seq_file *m)
+{
+	unsigned int bit;
+	long *facilities;
+
+	facilities = (long *)&S390_lowcore.stfle_fac_list;
+	seq_puts(m, "facilities      :");
+	for_each_set_bit_inv(bit, facilities, MAX_FACILITY_BIT)
+		seq_printf(m, " %d", bit);
+	seq_putc(m, '\n');
+}
+
+static void show_cpu_summary(struct seq_file *m, void *v)
+{
+	static const char *hwcap_str[] = {
+		"esan3", "zarch", "stfle", "msa", "ldisp", "eimm", "dfp",
+		"edat", "etf3eh", "highgprs", "te", "vx", "vxd", "vxe", "gs",
+		"vxe2", "vxp", "sort", "dflt"
+	};
+	static const char * const int_hwcap_str[] = {
+		"sie"
+	};
+	int i, cpu;
+
+	seq_printf(m, "vendor_id       : IBM/S390\n"
+		   "# processors    : %i\n"
+		   "bogomips per cpu: %lu.%02lu\n",
+		   num_online_cpus(), loops_per_jiffy/(500000/HZ),
+		   (loops_per_jiffy/(5000/HZ))%100);
+	seq_printf(m, "max thread id   : %d\n", smp_cpu_mtid);
+	seq_puts(m, "features\t: ");
+	for (i = 0; i < ARRAY_SIZE(hwcap_str); i++)
+		if (hwcap_str[i] && (elf_hwcap & (1UL << i)))
+			seq_printf(m, "%s ", hwcap_str[i]);
+	for (i = 0; i < ARRAY_SIZE(int_hwcap_str); i++)
+		if (int_hwcap_str[i] && (int_hwcap & (1UL << i)))
+			seq_printf(m, "%s ", int_hwcap_str[i]);
+	seq_puts(m, "\n");
+	show_facilities(m);
+	show_cacheinfo(m);
+	for_each_online_cpu(cpu) {
+		struct cpuid *id = &per_cpu(cpu_info.cpu_id, cpu);
+
+		seq_printf(m, "processor %d: "
+			   "version = %02X,  "
+			   "identification = %06X,  "
+			   "machine = %04X\n",
+			   cpu, id->version, id->ident, id->machine);
+	}
+}
+
+static void show_cpu_topology(struct seq_file *m, unsigned long n)
+{
+#ifdef CONFIG_SCHED_TOPOLOGY
+	seq_printf(m, "physical id     : %d\n", topology_physical_package_id(n));
+	seq_printf(m, "core id         : %d\n", topology_core_id(n));
+	seq_printf(m, "book id         : %d\n", topology_book_id(n));
+	seq_printf(m, "drawer id       : %d\n", topology_drawer_id(n));
+	seq_printf(m, "dedicated       : %d\n", topology_cpu_dedicated(n));
+	seq_printf(m, "address         : %d\n", smp_cpu_get_cpu_address(n));
+	seq_printf(m, "siblings        : %d\n", cpumask_weight(topology_core_cpumask(n)));
+	seq_printf(m, "cpu cores       : %d\n", topology_booted_cores(n));
+#endif /* CONFIG_SCHED_TOPOLOGY */
+}
+
+static void show_cpu_ids(struct seq_file *m, unsigned long n)
+{
+	struct cpuid *id = &per_cpu(cpu_info.cpu_id, n);
+
+	seq_printf(m, "version         : %02X\n", id->version);
+	seq_printf(m, "identification  : %06X\n", id->ident);
+	seq_printf(m, "machine         : %04X\n", id->machine);
+}
+
+static void show_cpu_mhz(struct seq_file *m, unsigned long n)
+{
+	struct cpu_info *c = per_cpu_ptr(&cpu_info, n);
+
+	if (!machine_has_cpu_mhz)
+		return;
+	seq_printf(m, "cpu MHz dynamic : %d\n", c->cpu_mhz_dynamic);
+	seq_printf(m, "cpu MHz static  : %d\n", c->cpu_mhz_static);
+}
+
+/*
+ * show_cpuinfo - Get information on one CPU for use by procfs.
+ */
+static int show_cpuinfo(struct seq_file *m, void *v)
+{
+	unsigned long n = (unsigned long) v - 1;
+	unsigned long first = cpumask_first(cpu_online_mask);
+
+	if (n == first)
+		show_cpu_summary(m, v);
+	seq_printf(m, "\ncpu number      : %ld\n", n);
+	show_cpu_topology(m, n);
+	show_cpu_ids(m, n);
+	show_cpu_mhz(m, n);
+	return 0;
+}
+
+static inline void *c_update(loff_t *pos)
+{
+	if (*pos)
+		*pos = cpumask_next(*pos - 1, cpu_online_mask);
+	else
+		*pos = cpumask_first(cpu_online_mask);
+	return *pos < nr_cpu_ids ? (void *)*pos + 1 : NULL;
+}
+
+static void *c_start(struct seq_file *m, loff_t *pos)
+{
+	get_online_cpus();
+	return c_update(pos);
+}
+
+static void *c_next(struct seq_file *m, void *v, loff_t *pos)
+{
+	++*pos;
+	return c_update(pos);
+}
+
+static void c_stop(struct seq_file *m, void *v)
+{
+	put_online_cpus();
+}
+
+const struct seq_operations cpuinfo_op = {
+	.start	= c_start,
+	.next	= c_next,
+	.stop	= c_stop,
+	.show	= show_cpuinfo,
+};
+
+int s390_isolate_bp(void)
+{
+	if (!test_facility(82))
+		return -EOPNOTSUPP;
+	set_thread_flag(TIF_ISOLATE_BP);
+	return 0;
+}
+EXPORT_SYMBOL(s390_isolate_bp);
+
+int s390_isolate_bp_guest(void)
+{
+	if (!test_facility(82))
+		return -EOPNOTSUPP;
+	set_thread_flag(TIF_ISOLATE_BP_GUEST);
+	return 0;
+}
+EXPORT_SYMBOL(s390_isolate_bp_guest);