1 /*
2 * @file op_model_amd.c
3 * athlon / K7 / K8 / Family 10h model-specific MSR operations
4 *
5 * @remark Copyright 2002-2009 OProfile authors
6 * @remark Read the file COPYING
7 *
8 * @author John Levon
9 * @author Philippe Elie
10 * @author Graydon Hoare
11 * @author Robert Richter <robert.richter@amd.com>
12 * @author Barry Kasindorf <barry.kasindorf@amd.com>
13 * @author Jason Yeh <jason.yeh@amd.com>
14 * @author Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
15 */
16
17 #include <linux/oprofile.h>
18 #include <linux/device.h>
19 #include <linux/pci.h>
20 #include <linux/percpu.h>
21
22 #include <asm/ptrace.h>
23 #include <asm/msr.h>
24 #include <asm/nmi.h>
25 #include <asm/apic.h>
26 #include <asm/processor.h>
27
28 #include "op_x86_model.h"
29 #include "op_counter.h"
30
31 #ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
32 #define NUM_VIRT_COUNTERS 32
33 #else
34 #define NUM_VIRT_COUNTERS 0
35 #endif
36
37 #define OP_EVENT_MASK 0x0FFF
38 #define OP_CTR_OVERFLOW (1ULL<<31)
39
40 #define MSR_AMD_EVENTSEL_RESERVED ((0xFFFFFCF0ULL<<32)|(1ULL<<21))
41
42 static int num_counters;
43 static unsigned long reset_value[OP_MAX_COUNTER];
44
45 #define IBS_FETCH_SIZE 6
46 #define IBS_OP_SIZE 12
47
48 static u32 ibs_caps;
49
50 struct ibs_config {
51 unsigned long op_enabled;
52 unsigned long fetch_enabled;
53 unsigned long max_cnt_fetch;
54 unsigned long max_cnt_op;
55 unsigned long rand_en;
56 unsigned long dispatched_ops;
57 unsigned long branch_target;
58 };
59
60 struct ibs_state {
61 u64 ibs_op_ctl;
62 int branch_target;
63 unsigned long sample_size;
64 };
65
66 static struct ibs_config ibs_config;
67 static struct ibs_state ibs_state;
68
69 /*
70 * IBS randomization macros
71 */
72 #define IBS_RANDOM_BITS 12
73 #define IBS_RANDOM_MASK ((1ULL << IBS_RANDOM_BITS) - 1)
74 #define IBS_RANDOM_MAXCNT_OFFSET (1ULL << (IBS_RANDOM_BITS - 5))
75
76 /*
77 * 16-bit Linear Feedback Shift Register (LFSR)
78 *
79 * 16 14 13 11
80 * Feedback polynomial = X + X + X + X + 1
81 */
lfsr_random(void)82 static unsigned int lfsr_random(void)
83 {
84 static unsigned int lfsr_value = 0xF00D;
85 unsigned int bit;
86
87 /* Compute next bit to shift in */
88 bit = ((lfsr_value >> 0) ^
89 (lfsr_value >> 2) ^
90 (lfsr_value >> 3) ^
91 (lfsr_value >> 5)) & 0x0001;
92
93 /* Advance to next register value */
94 lfsr_value = (lfsr_value >> 1) | (bit << 15);
95
96 return lfsr_value;
97 }
98
99 /*
100 * IBS software randomization
101 *
102 * The IBS periodic op counter is randomized in software. The lower 12
103 * bits of the 20 bit counter are randomized. IbsOpCurCnt is
104 * initialized with a 12 bit random value.
105 */
op_amd_randomize_ibs_op(u64 val)106 static inline u64 op_amd_randomize_ibs_op(u64 val)
107 {
108 unsigned int random = lfsr_random();
109
110 if (!(ibs_caps & IBS_CAPS_RDWROPCNT))
111 /*
112 * Work around if the hw can not write to IbsOpCurCnt
113 *
114 * Randomize the lower 8 bits of the 16 bit
115 * IbsOpMaxCnt [15:0] value in the range of -128 to
116 * +127 by adding/subtracting an offset to the
117 * maximum count (IbsOpMaxCnt).
118 *
119 * To avoid over or underflows and protect upper bits
120 * starting at bit 16, the initial value for
121 * IbsOpMaxCnt must fit in the range from 0x0081 to
122 * 0xff80.
123 */
124 val += (s8)(random >> 4);
125 else
126 val |= (u64)(random & IBS_RANDOM_MASK) << 32;
127
128 return val;
129 }
130
131 static inline void
op_amd_handle_ibs(struct pt_regs * const regs,struct op_msrs const * const msrs)132 op_amd_handle_ibs(struct pt_regs * const regs,
133 struct op_msrs const * const msrs)
134 {
135 u64 val, ctl;
136 struct op_entry entry;
137
138 if (!ibs_caps)
139 return;
140
141 if (ibs_config.fetch_enabled) {
142 rdmsrl(MSR_AMD64_IBSFETCHCTL, ctl);
143 if (ctl & IBS_FETCH_VAL) {
144 rdmsrl(MSR_AMD64_IBSFETCHLINAD, val);
145 oprofile_write_reserve(&entry, regs, val,
146 IBS_FETCH_CODE, IBS_FETCH_SIZE);
147 oprofile_add_data64(&entry, val);
148 oprofile_add_data64(&entry, ctl);
149 rdmsrl(MSR_AMD64_IBSFETCHPHYSAD, val);
150 oprofile_add_data64(&entry, val);
151 oprofile_write_commit(&entry);
152
153 /* reenable the IRQ */
154 ctl &= ~(IBS_FETCH_VAL | IBS_FETCH_CNT);
155 ctl |= IBS_FETCH_ENABLE;
156 wrmsrl(MSR_AMD64_IBSFETCHCTL, ctl);
157 }
158 }
159
160 if (ibs_config.op_enabled) {
161 rdmsrl(MSR_AMD64_IBSOPCTL, ctl);
162 if (ctl & IBS_OP_VAL) {
163 rdmsrl(MSR_AMD64_IBSOPRIP, val);
164 oprofile_write_reserve(&entry, regs, val, IBS_OP_CODE,
165 ibs_state.sample_size);
166 oprofile_add_data64(&entry, val);
167 rdmsrl(MSR_AMD64_IBSOPDATA, val);
168 oprofile_add_data64(&entry, val);
169 rdmsrl(MSR_AMD64_IBSOPDATA2, val);
170 oprofile_add_data64(&entry, val);
171 rdmsrl(MSR_AMD64_IBSOPDATA3, val);
172 oprofile_add_data64(&entry, val);
173 rdmsrl(MSR_AMD64_IBSDCLINAD, val);
174 oprofile_add_data64(&entry, val);
175 rdmsrl(MSR_AMD64_IBSDCPHYSAD, val);
176 oprofile_add_data64(&entry, val);
177 if (ibs_state.branch_target) {
178 rdmsrl(MSR_AMD64_IBSBRTARGET, val);
179 oprofile_add_data(&entry, (unsigned long)val);
180 }
181 oprofile_write_commit(&entry);
182
183 /* reenable the IRQ */
184 ctl = op_amd_randomize_ibs_op(ibs_state.ibs_op_ctl);
185 wrmsrl(MSR_AMD64_IBSOPCTL, ctl);
186 }
187 }
188 }
189
op_amd_start_ibs(void)190 static inline void op_amd_start_ibs(void)
191 {
192 u64 val;
193
194 if (!ibs_caps)
195 return;
196
197 memset(&ibs_state, 0, sizeof(ibs_state));
198
199 /*
200 * Note: Since the max count settings may out of range we
201 * write back the actual used values so that userland can read
202 * it.
203 */
204
205 if (ibs_config.fetch_enabled) {
206 val = ibs_config.max_cnt_fetch >> 4;
207 val = min(val, IBS_FETCH_MAX_CNT);
208 ibs_config.max_cnt_fetch = val << 4;
209 val |= ibs_config.rand_en ? IBS_FETCH_RAND_EN : 0;
210 val |= IBS_FETCH_ENABLE;
211 wrmsrl(MSR_AMD64_IBSFETCHCTL, val);
212 }
213
214 if (ibs_config.op_enabled) {
215 val = ibs_config.max_cnt_op >> 4;
216 if (!(ibs_caps & IBS_CAPS_RDWROPCNT)) {
217 /*
218 * IbsOpCurCnt not supported. See
219 * op_amd_randomize_ibs_op() for details.
220 */
221 val = clamp(val, 0x0081ULL, 0xFF80ULL);
222 ibs_config.max_cnt_op = val << 4;
223 } else {
224 /*
225 * The start value is randomized with a
226 * positive offset, we need to compensate it
227 * with the half of the randomized range. Also
228 * avoid underflows.
229 */
230 val += IBS_RANDOM_MAXCNT_OFFSET;
231 if (ibs_caps & IBS_CAPS_OPCNTEXT)
232 val = min(val, IBS_OP_MAX_CNT_EXT);
233 else
234 val = min(val, IBS_OP_MAX_CNT);
235 ibs_config.max_cnt_op =
236 (val - IBS_RANDOM_MAXCNT_OFFSET) << 4;
237 }
238 val = ((val & ~IBS_OP_MAX_CNT) << 4) | (val & IBS_OP_MAX_CNT);
239 val |= ibs_config.dispatched_ops ? IBS_OP_CNT_CTL : 0;
240 val |= IBS_OP_ENABLE;
241 ibs_state.ibs_op_ctl = val;
242 ibs_state.sample_size = IBS_OP_SIZE;
243 if (ibs_config.branch_target) {
244 ibs_state.branch_target = 1;
245 ibs_state.sample_size++;
246 }
247 val = op_amd_randomize_ibs_op(ibs_state.ibs_op_ctl);
248 wrmsrl(MSR_AMD64_IBSOPCTL, val);
249 }
250 }
251
op_amd_stop_ibs(void)252 static void op_amd_stop_ibs(void)
253 {
254 if (!ibs_caps)
255 return;
256
257 if (ibs_config.fetch_enabled)
258 /* clear max count and enable */
259 wrmsrl(MSR_AMD64_IBSFETCHCTL, 0);
260
261 if (ibs_config.op_enabled)
262 /* clear max count and enable */
263 wrmsrl(MSR_AMD64_IBSOPCTL, 0);
264 }
265
266 #ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
267
op_mux_switch_ctrl(struct op_x86_model_spec const * model,struct op_msrs const * const msrs)268 static void op_mux_switch_ctrl(struct op_x86_model_spec const *model,
269 struct op_msrs const * const msrs)
270 {
271 u64 val;
272 int i;
273
274 /* enable active counters */
275 for (i = 0; i < num_counters; ++i) {
276 int virt = op_x86_phys_to_virt(i);
277 if (!reset_value[virt])
278 continue;
279 rdmsrl(msrs->controls[i].addr, val);
280 val &= model->reserved;
281 val |= op_x86_get_ctrl(model, &counter_config[virt]);
282 wrmsrl(msrs->controls[i].addr, val);
283 }
284 }
285
286 #endif
287
288 /* functions for op_amd_spec */
289
op_amd_shutdown(struct op_msrs const * const msrs)290 static void op_amd_shutdown(struct op_msrs const * const msrs)
291 {
292 int i;
293
294 for (i = 0; i < num_counters; ++i) {
295 if (!msrs->counters[i].addr)
296 continue;
297 release_perfctr_nmi(MSR_K7_PERFCTR0 + i);
298 release_evntsel_nmi(MSR_K7_EVNTSEL0 + i);
299 }
300 }
301
op_amd_fill_in_addresses(struct op_msrs * const msrs)302 static int op_amd_fill_in_addresses(struct op_msrs * const msrs)
303 {
304 int i;
305
306 for (i = 0; i < num_counters; i++) {
307 if (!reserve_perfctr_nmi(MSR_K7_PERFCTR0 + i))
308 goto fail;
309 if (!reserve_evntsel_nmi(MSR_K7_EVNTSEL0 + i)) {
310 release_perfctr_nmi(MSR_K7_PERFCTR0 + i);
311 goto fail;
312 }
313 /* both registers must be reserved */
314 if (num_counters == AMD64_NUM_COUNTERS_CORE) {
315 msrs->counters[i].addr = MSR_F15H_PERF_CTR + (i << 1);
316 msrs->controls[i].addr = MSR_F15H_PERF_CTL + (i << 1);
317 } else {
318 msrs->controls[i].addr = MSR_K7_EVNTSEL0 + i;
319 msrs->counters[i].addr = MSR_K7_PERFCTR0 + i;
320 }
321 continue;
322 fail:
323 if (!counter_config[i].enabled)
324 continue;
325 op_x86_warn_reserved(i);
326 op_amd_shutdown(msrs);
327 return -EBUSY;
328 }
329
330 return 0;
331 }
332
op_amd_setup_ctrs(struct op_x86_model_spec const * model,struct op_msrs const * const msrs)333 static void op_amd_setup_ctrs(struct op_x86_model_spec const *model,
334 struct op_msrs const * const msrs)
335 {
336 u64 val;
337 int i;
338
339 /* setup reset_value */
340 for (i = 0; i < OP_MAX_COUNTER; ++i) {
341 if (counter_config[i].enabled
342 && msrs->counters[op_x86_virt_to_phys(i)].addr)
343 reset_value[i] = counter_config[i].count;
344 else
345 reset_value[i] = 0;
346 }
347
348 /* clear all counters */
349 for (i = 0; i < num_counters; ++i) {
350 if (!msrs->controls[i].addr)
351 continue;
352 rdmsrl(msrs->controls[i].addr, val);
353 if (val & ARCH_PERFMON_EVENTSEL_ENABLE)
354 op_x86_warn_in_use(i);
355 val &= model->reserved;
356 wrmsrl(msrs->controls[i].addr, val);
357 /*
358 * avoid a false detection of ctr overflows in NMI
359 * handler
360 */
361 wrmsrl(msrs->counters[i].addr, -1LL);
362 }
363
364 /* enable active counters */
365 for (i = 0; i < num_counters; ++i) {
366 int virt = op_x86_phys_to_virt(i);
367 if (!reset_value[virt])
368 continue;
369
370 /* setup counter registers */
371 wrmsrl(msrs->counters[i].addr, -(u64)reset_value[virt]);
372
373 /* setup control registers */
374 rdmsrl(msrs->controls[i].addr, val);
375 val &= model->reserved;
376 val |= op_x86_get_ctrl(model, &counter_config[virt]);
377 wrmsrl(msrs->controls[i].addr, val);
378 }
379 }
380
op_amd_check_ctrs(struct pt_regs * const regs,struct op_msrs const * const msrs)381 static int op_amd_check_ctrs(struct pt_regs * const regs,
382 struct op_msrs const * const msrs)
383 {
384 u64 val;
385 int i;
386
387 for (i = 0; i < num_counters; ++i) {
388 int virt = op_x86_phys_to_virt(i);
389 if (!reset_value[virt])
390 continue;
391 rdmsrl(msrs->counters[i].addr, val);
392 /* bit is clear if overflowed: */
393 if (val & OP_CTR_OVERFLOW)
394 continue;
395 oprofile_add_sample(regs, virt);
396 wrmsrl(msrs->counters[i].addr, -(u64)reset_value[virt]);
397 }
398
399 op_amd_handle_ibs(regs, msrs);
400
401 /* See op_model_ppro.c */
402 return 1;
403 }
404
op_amd_start(struct op_msrs const * const msrs)405 static void op_amd_start(struct op_msrs const * const msrs)
406 {
407 u64 val;
408 int i;
409
410 for (i = 0; i < num_counters; ++i) {
411 if (!reset_value[op_x86_phys_to_virt(i)])
412 continue;
413 rdmsrl(msrs->controls[i].addr, val);
414 val |= ARCH_PERFMON_EVENTSEL_ENABLE;
415 wrmsrl(msrs->controls[i].addr, val);
416 }
417
418 op_amd_start_ibs();
419 }
420
op_amd_stop(struct op_msrs const * const msrs)421 static void op_amd_stop(struct op_msrs const * const msrs)
422 {
423 u64 val;
424 int i;
425
426 /*
427 * Subtle: stop on all counters to avoid race with setting our
428 * pm callback
429 */
430 for (i = 0; i < num_counters; ++i) {
431 if (!reset_value[op_x86_phys_to_virt(i)])
432 continue;
433 rdmsrl(msrs->controls[i].addr, val);
434 val &= ~ARCH_PERFMON_EVENTSEL_ENABLE;
435 wrmsrl(msrs->controls[i].addr, val);
436 }
437
438 op_amd_stop_ibs();
439 }
440
441 /*
442 * check and reserve APIC extended interrupt LVT offset for IBS if
443 * available
444 */
445
init_ibs(void)446 static void init_ibs(void)
447 {
448 ibs_caps = get_ibs_caps();
449
450 if (!ibs_caps)
451 return;
452
453 printk(KERN_INFO "oprofile: AMD IBS detected (0x%08x)\n", ibs_caps);
454 }
455
456 static int (*create_arch_files)(struct dentry *root);
457
setup_ibs_files(struct dentry * root)458 static int setup_ibs_files(struct dentry *root)
459 {
460 struct dentry *dir;
461 int ret = 0;
462
463 /* architecture specific files */
464 if (create_arch_files)
465 ret = create_arch_files(root);
466
467 if (ret)
468 return ret;
469
470 if (!ibs_caps)
471 return ret;
472
473 /* model specific files */
474
475 /* setup some reasonable defaults */
476 memset(&ibs_config, 0, sizeof(ibs_config));
477 ibs_config.max_cnt_fetch = 250000;
478 ibs_config.max_cnt_op = 250000;
479
480 if (ibs_caps & IBS_CAPS_FETCHSAM) {
481 dir = oprofilefs_mkdir(root, "ibs_fetch");
482 oprofilefs_create_ulong(dir, "enable",
483 &ibs_config.fetch_enabled);
484 oprofilefs_create_ulong(dir, "max_count",
485 &ibs_config.max_cnt_fetch);
486 oprofilefs_create_ulong(dir, "rand_enable",
487 &ibs_config.rand_en);
488 }
489
490 if (ibs_caps & IBS_CAPS_OPSAM) {
491 dir = oprofilefs_mkdir(root, "ibs_op");
492 oprofilefs_create_ulong(dir, "enable",
493 &ibs_config.op_enabled);
494 oprofilefs_create_ulong(dir, "max_count",
495 &ibs_config.max_cnt_op);
496 if (ibs_caps & IBS_CAPS_OPCNT)
497 oprofilefs_create_ulong(dir, "dispatched_ops",
498 &ibs_config.dispatched_ops);
499 if (ibs_caps & IBS_CAPS_BRNTRGT)
500 oprofilefs_create_ulong(dir, "branch_target",
501 &ibs_config.branch_target);
502 }
503
504 return 0;
505 }
506
507 struct op_x86_model_spec op_amd_spec;
508
op_amd_init(struct oprofile_operations * ops)509 static int op_amd_init(struct oprofile_operations *ops)
510 {
511 init_ibs();
512 create_arch_files = ops->create_files;
513 ops->create_files = setup_ibs_files;
514
515 if (boot_cpu_data.x86 == 0x15) {
516 num_counters = AMD64_NUM_COUNTERS_CORE;
517 } else {
518 num_counters = AMD64_NUM_COUNTERS;
519 }
520
521 op_amd_spec.num_counters = num_counters;
522 op_amd_spec.num_controls = num_counters;
523 op_amd_spec.num_virt_counters = max(num_counters, NUM_VIRT_COUNTERS);
524
525 return 0;
526 }
527
528 struct op_x86_model_spec op_amd_spec = {
529 /* num_counters/num_controls filled in at runtime */
530 .reserved = MSR_AMD_EVENTSEL_RESERVED,
531 .event_mask = OP_EVENT_MASK,
532 .init = op_amd_init,
533 .fill_in_addresses = &op_amd_fill_in_addresses,
534 .setup_ctrs = &op_amd_setup_ctrs,
535 .check_ctrs = &op_amd_check_ctrs,
536 .start = &op_amd_start,
537 .stop = &op_amd_stop,
538 .shutdown = &op_amd_shutdown,
539 #ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
540 .switch_ctrl = &op_mux_switch_ctrl,
541 #endif
542 };
543