summaryrefslogtreecommitdiffstats
path: root/arch/s390/kernel/topology.c
blob: 632b13e100538704758cea2eebd75c6cfdc15bf7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
/*
 *    Copyright IBM Corp. 2007
 *    Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
 */

#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/bootmem.h>
#include <linux/sched.h>
#include <linux/workqueue.h>
#include <linux/cpu.h>
#include <linux/smp.h>
#include <asm/delay.h>
#include <asm/s390_ext.h>
#include <asm/sysinfo.h>

#define CPU_BITS 64
#define NR_MAG 6

#define PTF_HORIZONTAL	(0UL)
#define PTF_VERTICAL	(1UL)
#define PTF_CHECK	(2UL)

struct tl_cpu {
	unsigned char reserved0[4];
	unsigned char :6;
	unsigned char pp:2;
	unsigned char reserved1;
	unsigned short origin;
	unsigned long mask[CPU_BITS / BITS_PER_LONG];
};

struct tl_container {
	unsigned char reserved[8];
};

union tl_entry {
	unsigned char nl;
	struct tl_cpu cpu;
	struct tl_container container;
};

struct tl_info {
	unsigned char reserved0[2];
	unsigned short length;
	unsigned char mag[NR_MAG];
	unsigned char reserved1;
	unsigned char mnest;
	unsigned char reserved2[4];
	union tl_entry tle[0];
};

struct core_info {
	struct core_info *next;
	cpumask_t mask;
};

static void topology_work_fn(struct work_struct *work);
static struct tl_info *tl_info;
static struct core_info core_info;
static int machine_has_topology;
static int machine_has_topology_irq;
static struct timer_list topology_timer;
static void set_topology_timer(void);
static DECLARE_WORK(topology_work, topology_work_fn);

cpumask_t cpu_core_map[NR_CPUS];

cpumask_t cpu_coregroup_map(unsigned int cpu)
{
	struct core_info *core = &core_info;
	cpumask_t mask;

	cpus_clear(mask);
	if (!machine_has_topology)
		return cpu_present_map;
	mutex_lock(&smp_cpu_state_mutex);
	while (core) {
		if (cpu_isset(cpu, core->mask)) {
			mask = core->mask;
			break;
		}
		core = core->next;
	}
	mutex_unlock(&smp_cpu_state_mutex);
	if (cpus_empty(mask))
		mask = cpumask_of_cpu(cpu);
	return mask;
}

static void add_cpus_to_core(struct tl_cpu *tl_cpu, struct core_info *core)
{
	unsigned int cpu;

	for (cpu = find_first_bit(&tl_cpu->mask[0], CPU_BITS);
	     cpu < CPU_BITS;
	     cpu = find_next_bit(&tl_cpu->mask[0], CPU_BITS, cpu + 1))
	{
		unsigned int rcpu, lcpu;

		rcpu = CPU_BITS - 1 - cpu + tl_cpu->origin;
		for_each_present_cpu(lcpu) {
			if (__cpu_logical_map[lcpu] == rcpu) {
				cpu_set(lcpu, core->mask);
				smp_cpu_polarization[lcpu] = tl_cpu->pp;
			}
		}
	}
}

static void clear_cores(void)
{
	struct core_info *core = &core_info;

	while (core) {
		cpus_clear(core->mask);
		core = core->next;
	}
}

static union tl_entry *next_tle(union tl_entry *tle)
{
	if (tle->nl)
		return (union tl_entry *)((struct tl_container *)tle + 1);
	else
		return (union tl_entry *)((struct tl_cpu *)tle + 1);
}

static void tl_to_cores(struct tl_info *info)
{
	union tl_entry *tle, *end;
	struct core_info *core = &core_info;

	mutex_lock(&smp_cpu_state_mutex);
	clear_cores();
	tle = info->tle;
	end = (union tl_entry *)((unsigned long)info + info->length);
	while (tle < end) {
		switch (tle->nl) {
		case 5:
		case 4:
		case 3:
		case 2:
			break;
		case 1:
			core = core->next;
			break;
		case 0:
			add_cpus_to_core(&tle->cpu, core);
			break;
		default:
			clear_cores();
			machine_has_topology = 0;
			return;
		}
		tle = next_tle(tle);
	}
	mutex_unlock(&smp_cpu_state_mutex);
}

static void topology_update_polarization_simple(void)
{
	int cpu;

	mutex_lock(&smp_cpu_state_mutex);
	for_each_present_cpu(cpu)
		smp_cpu_polarization[cpu] = POLARIZATION_HRZ;
	mutex_unlock(&smp_cpu_state_mutex);
}

static int ptf(unsigned long fc)
{
	int rc;

	asm volatile(
		"	.insn	rre,0xb9a20000,%1,%1\n"
		"	ipm	%0\n"
		"	srl	%0,28\n"
		: "=d" (rc)
		: "d" (fc)  : "cc");
	return rc;
}

int topology_set_cpu_management(int fc)
{
	int cpu;
	int rc;

	if (!machine_has_topology)
		return -EOPNOTSUPP;
	if (fc)
		rc = ptf(PTF_VERTICAL);
	else
		rc = ptf(PTF_HORIZONTAL);
	if (rc)
		return -EBUSY;
	for_each_present_cpu(cpu)
		smp_cpu_polarization[cpu] = POLARIZATION_UNKNWN;
	return rc;
}

static void update_cpu_core_map(void)
{
	int cpu;

	for_each_present_cpu(cpu)
		cpu_core_map[cpu] = cpu_coregroup_map(cpu);
}

void arch_update_cpu_topology(void)
{
	struct tl_info *info = tl_info;
	struct sys_device *sysdev;
	int cpu;

	if (!machine_has_topology) {
		update_cpu_core_map();
		topology_update_polarization_simple();
		return;
	}
	stsi(info, 15, 1, 2);
	tl_to_cores(info);
	update_cpu_core_map();
	for_each_online_cpu(cpu) {
		sysdev = get_cpu_sysdev(cpu);
		kobject_uevent(&sysdev->kobj, KOBJ_CHANGE);
	}
}

static void topology_work_fn(struct work_struct *work)
{
	arch_reinit_sched_domains();
}

void topology_schedule_update(void)
{
	schedule_work(&topology_work);
}

static void topology_timer_fn(unsigned long ignored)
{
	if (ptf(PTF_CHECK))
		topology_schedule_update();
	set_topology_timer();
}

static void set_topology_timer(void)
{
	topology_timer.function = topology_timer_fn;
	topology_timer.data = 0;
	topology_timer.expires = jiffies + 60 * HZ;
	add_timer(&topology_timer);
}

static void topology_interrupt(__u16 code)
{
	schedule_work(&topology_work);
}

static int __init init_topology_update(void)
{
	int rc;

	rc = 0;
	if (!machine_has_topology) {
		topology_update_polarization_simple();
		goto out;
	}
	init_timer_deferrable(&topology_timer);
	if (machine_has_topology_irq) {
		rc = register_external_interrupt(0x2005, topology_interrupt);
		if (rc)
			goto out;
		ctl_set_bit(0, 8);
	}
	else
		set_topology_timer();
out:
	update_cpu_core_map();
	return rc;
}
__initcall(init_topology_update);

void __init s390_init_cpu_topology(void)
{
	unsigned long long facility_bits;
	struct tl_info *info;
	struct core_info *core;
	int nr_cores;
	int i;

	if (stfle(&facility_bits, 1) <= 0)
		return;
	if (!(facility_bits & (1ULL << 52)) || !(facility_bits & (1ULL << 61)))
		return;
	machine_has_topology = 1;

	if (facility_bits & (1ULL << 51))
		machine_has_topology_irq = 1;

	tl_info = alloc_bootmem_pages(PAGE_SIZE);
	info = tl_info;
	stsi(info, 15, 1, 2);

	nr_cores = info->mag[NR_MAG - 2];
	for (i = 0; i < info->mnest - 2; i++)
		nr_cores *= info->mag[NR_MAG - 3 - i];

	printk(KERN_INFO "CPU topology:");
	for (i = 0; i < NR_MAG; i++)
		printk(" %d", info->mag[i]);
	printk(" / %d\n", info->mnest);

	core = &core_info;
	for (i = 0; i < nr_cores; i++) {
		core->next = alloc_bootmem(sizeof(struct core_info));
		core = core->next;
		if (!core)
			goto error;
	}
	return;
error:
	machine_has_topology = 0;
	machine_has_topology_irq = 0;
}
OpenPOWER on IntegriCloud