1 /**
2 * op_model_v7.c
3 * ARM V7 (Cortex A8) Event Monitor Driver
4 *
5 * Copyright 2008 Jean Pihet <jpihet@mvista.com>
6 * Copyright 2004 ARM SMP Development Team
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12 #include <linux/types.h>
13 #include <linux/errno.h>
14 #include <linux/oprofile.h>
15 #include <linux/interrupt.h>
16 #include <linux/irq.h>
17 #include <linux/smp.h>
18
19 #include "op_counter.h"
20 #include "op_arm_model.h"
21 #include "op_model_v7.h"
22
23 /* #define DEBUG */
24
25
26 /*
27 * ARM V7 PMNC support
28 */
29
30 static u32 cnt_en[CNTMAX];
31
armv7_pmnc_write(u32 val)32 static inline void armv7_pmnc_write(u32 val)
33 {
34 val &= PMNC_MASK;
35 asm volatile("mcr p15, 0, %0, c9, c12, 0" : : "r" (val));
36 }
37
armv7_pmnc_read(void)38 static inline u32 armv7_pmnc_read(void)
39 {
40 u32 val;
41
42 asm volatile("mrc p15, 0, %0, c9, c12, 0" : "=r" (val));
43 return val;
44 }
45
armv7_pmnc_enable_counter(unsigned int cnt)46 static inline u32 armv7_pmnc_enable_counter(unsigned int cnt)
47 {
48 u32 val;
49
50 if (cnt >= CNTMAX) {
51 printk(KERN_ERR "oprofile: CPU%u enabling wrong PMNC counter"
52 " %d\n", smp_processor_id(), cnt);
53 return -1;
54 }
55
56 if (cnt == CCNT)
57 val = CNTENS_C;
58 else
59 val = (1 << (cnt - CNT0));
60
61 val &= CNTENS_MASK;
62 asm volatile("mcr p15, 0, %0, c9, c12, 1" : : "r" (val));
63
64 return cnt;
65 }
66
armv7_pmnc_disable_counter(unsigned int cnt)67 static inline u32 armv7_pmnc_disable_counter(unsigned int cnt)
68 {
69 u32 val;
70
71 if (cnt >= CNTMAX) {
72 printk(KERN_ERR "oprofile: CPU%u disabling wrong PMNC counter"
73 " %d\n", smp_processor_id(), cnt);
74 return -1;
75 }
76
77 if (cnt == CCNT)
78 val = CNTENC_C;
79 else
80 val = (1 << (cnt - CNT0));
81
82 val &= CNTENC_MASK;
83 asm volatile("mcr p15, 0, %0, c9, c12, 2" : : "r" (val));
84
85 return cnt;
86 }
87
armv7_pmnc_enable_intens(unsigned int cnt)88 static inline u32 armv7_pmnc_enable_intens(unsigned int cnt)
89 {
90 u32 val;
91
92 if (cnt >= CNTMAX) {
93 printk(KERN_ERR "oprofile: CPU%u enabling wrong PMNC counter"
94 " interrupt enable %d\n", smp_processor_id(), cnt);
95 return -1;
96 }
97
98 if (cnt == CCNT)
99 val = INTENS_C;
100 else
101 val = (1 << (cnt - CNT0));
102
103 val &= INTENS_MASK;
104 asm volatile("mcr p15, 0, %0, c9, c14, 1" : : "r" (val));
105
106 return cnt;
107 }
108
armv7_pmnc_getreset_flags(void)109 static inline u32 armv7_pmnc_getreset_flags(void)
110 {
111 u32 val;
112
113 /* Read */
114 asm volatile("mrc p15, 0, %0, c9, c12, 3" : "=r" (val));
115
116 /* Write to clear flags */
117 val &= FLAG_MASK;
118 asm volatile("mcr p15, 0, %0, c9, c12, 3" : : "r" (val));
119
120 return val;
121 }
122
armv7_pmnc_select_counter(unsigned int cnt)123 static inline int armv7_pmnc_select_counter(unsigned int cnt)
124 {
125 u32 val;
126
127 if ((cnt == CCNT) || (cnt >= CNTMAX)) {
128 printk(KERN_ERR "oprofile: CPU%u selecting wrong PMNC counteri"
129 " %d\n", smp_processor_id(), cnt);
130 return -1;
131 }
132
133 val = (cnt - CNT0) & SELECT_MASK;
134 asm volatile("mcr p15, 0, %0, c9, c12, 5" : : "r" (val));
135
136 return cnt;
137 }
138
armv7_pmnc_write_evtsel(unsigned int cnt,u32 val)139 static inline void armv7_pmnc_write_evtsel(unsigned int cnt, u32 val)
140 {
141 if (armv7_pmnc_select_counter(cnt) == cnt) {
142 val &= EVTSEL_MASK;
143 asm volatile("mcr p15, 0, %0, c9, c13, 1" : : "r" (val));
144 }
145 }
146
armv7_pmnc_reset_counter(unsigned int cnt)147 static void armv7_pmnc_reset_counter(unsigned int cnt)
148 {
149 u32 cpu_cnt = CPU_COUNTER(smp_processor_id(), cnt);
150 u32 val = -(u32)counter_config[cpu_cnt].count;
151
152 switch (cnt) {
153 case CCNT:
154 armv7_pmnc_disable_counter(cnt);
155
156 asm volatile("mcr p15, 0, %0, c9, c13, 0" : : "r" (val));
157
158 if (cnt_en[cnt] != 0)
159 armv7_pmnc_enable_counter(cnt);
160
161 break;
162
163 case CNT0:
164 case CNT1:
165 case CNT2:
166 case CNT3:
167 armv7_pmnc_disable_counter(cnt);
168
169 if (armv7_pmnc_select_counter(cnt) == cnt)
170 asm volatile("mcr p15, 0, %0, c9, c13, 2" : : "r" (val));
171
172 if (cnt_en[cnt] != 0)
173 armv7_pmnc_enable_counter(cnt);
174
175 break;
176
177 default:
178 printk(KERN_ERR "oprofile: CPU%u resetting wrong PMNC counter"
179 " %d\n", smp_processor_id(), cnt);
180 break;
181 }
182 }
183
armv7_setup_pmnc(void)184 int armv7_setup_pmnc(void)
185 {
186 unsigned int cnt;
187
188 if (armv7_pmnc_read() & PMNC_E) {
189 printk(KERN_ERR "oprofile: CPU%u PMNC still enabled when setup"
190 " new event counter.\n", smp_processor_id());
191 return -EBUSY;
192 }
193
194 /*
195 * Initialize & Reset PMNC: C bit, D bit and P bit.
196 * Note: Using a slower count for CCNT (D bit: divide by 64) results
197 * in a more stable system
198 */
199 armv7_pmnc_write(PMNC_P | PMNC_C | PMNC_D);
200
201
202 for (cnt = CCNT; cnt < CNTMAX; cnt++) {
203 unsigned long event;
204 u32 cpu_cnt = CPU_COUNTER(smp_processor_id(), cnt);
205
206 /*
207 * Disable counter
208 */
209 armv7_pmnc_disable_counter(cnt);
210 cnt_en[cnt] = 0;
211
212 if (!counter_config[cpu_cnt].enabled)
213 continue;
214
215 event = counter_config[cpu_cnt].event & 255;
216
217 /*
218 * Set event (if destined for PMNx counters)
219 * We don't need to set the event if it's a cycle count
220 */
221 if (cnt != CCNT)
222 armv7_pmnc_write_evtsel(cnt, event);
223
224 /*
225 * Enable interrupt for this counter
226 */
227 armv7_pmnc_enable_intens(cnt);
228
229 /*
230 * Reset counter
231 */
232 armv7_pmnc_reset_counter(cnt);
233
234 /*
235 * Enable counter
236 */
237 armv7_pmnc_enable_counter(cnt);
238 cnt_en[cnt] = 1;
239 }
240
241 return 0;
242 }
243
armv7_start_pmnc(void)244 static inline void armv7_start_pmnc(void)
245 {
246 armv7_pmnc_write(armv7_pmnc_read() | PMNC_E);
247 }
248
armv7_stop_pmnc(void)249 static inline void armv7_stop_pmnc(void)
250 {
251 armv7_pmnc_write(armv7_pmnc_read() & ~PMNC_E);
252 }
253
254 /*
255 * CPU counters' IRQ handler (one IRQ per CPU)
256 */
armv7_pmnc_interrupt(int irq,void * arg)257 static irqreturn_t armv7_pmnc_interrupt(int irq, void *arg)
258 {
259 struct pt_regs *regs = get_irq_regs();
260 unsigned int cnt;
261 u32 flags;
262
263
264 /*
265 * Stop IRQ generation
266 */
267 armv7_stop_pmnc();
268
269 /*
270 * Get and reset overflow status flags
271 */
272 flags = armv7_pmnc_getreset_flags();
273
274 /*
275 * Cycle counter
276 */
277 if (flags & FLAG_C) {
278 u32 cpu_cnt = CPU_COUNTER(smp_processor_id(), CCNT);
279 armv7_pmnc_reset_counter(CCNT);
280 oprofile_add_sample(regs, cpu_cnt);
281 }
282
283 /*
284 * PMNC counters 0:3
285 */
286 for (cnt = CNT0; cnt < CNTMAX; cnt++) {
287 if (flags & (1 << (cnt - CNT0))) {
288 u32 cpu_cnt = CPU_COUNTER(smp_processor_id(), cnt);
289 armv7_pmnc_reset_counter(cnt);
290 oprofile_add_sample(regs, cpu_cnt);
291 }
292 }
293
294 /*
295 * Allow IRQ generation
296 */
297 armv7_start_pmnc();
298
299 return IRQ_HANDLED;
300 }
301
armv7_request_interrupts(int * irqs,int nr)302 int armv7_request_interrupts(int *irqs, int nr)
303 {
304 unsigned int i;
305 int ret = 0;
306
307 for (i = 0; i < nr; i++) {
308 ret = request_irq(irqs[i], armv7_pmnc_interrupt,
309 IRQF_DISABLED, "CP15 PMNC", NULL);
310 if (ret != 0) {
311 printk(KERN_ERR "oprofile: unable to request IRQ%u"
312 " for ARMv7\n",
313 irqs[i]);
314 break;
315 }
316 }
317
318 if (i != nr)
319 while (i-- != 0)
320 free_irq(irqs[i], NULL);
321
322 return ret;
323 }
324
armv7_release_interrupts(int * irqs,int nr)325 void armv7_release_interrupts(int *irqs, int nr)
326 {
327 unsigned int i;
328
329 for (i = 0; i < nr; i++)
330 free_irq(irqs[i], NULL);
331 }
332
333 #ifdef DEBUG
armv7_pmnc_dump_regs(void)334 static void armv7_pmnc_dump_regs(void)
335 {
336 u32 val;
337 unsigned int cnt;
338
339 printk(KERN_INFO "PMNC registers dump:\n");
340
341 asm volatile("mrc p15, 0, %0, c9, c12, 0" : "=r" (val));
342 printk(KERN_INFO "PMNC =0x%08x\n", val);
343
344 asm volatile("mrc p15, 0, %0, c9, c12, 1" : "=r" (val));
345 printk(KERN_INFO "CNTENS=0x%08x\n", val);
346
347 asm volatile("mrc p15, 0, %0, c9, c14, 1" : "=r" (val));
348 printk(KERN_INFO "INTENS=0x%08x\n", val);
349
350 asm volatile("mrc p15, 0, %0, c9, c12, 3" : "=r" (val));
351 printk(KERN_INFO "FLAGS =0x%08x\n", val);
352
353 asm volatile("mrc p15, 0, %0, c9, c12, 5" : "=r" (val));
354 printk(KERN_INFO "SELECT=0x%08x\n", val);
355
356 asm volatile("mrc p15, 0, %0, c9, c13, 0" : "=r" (val));
357 printk(KERN_INFO "CCNT =0x%08x\n", val);
358
359 for (cnt = CNT0; cnt < CNTMAX; cnt++) {
360 armv7_pmnc_select_counter(cnt);
361 asm volatile("mrc p15, 0, %0, c9, c13, 2" : "=r" (val));
362 printk(KERN_INFO "CNT[%d] count =0x%08x\n", cnt-CNT0, val);
363 asm volatile("mrc p15, 0, %0, c9, c13, 1" : "=r" (val));
364 printk(KERN_INFO "CNT[%d] evtsel=0x%08x\n", cnt-CNT0, val);
365 }
366 }
367 #endif
368
369
370 static int irqs[] = {
371 #ifdef CONFIG_ARCH_OMAP3
372 INT_34XX_BENCH_MPU_EMUL,
373 #endif
374 };
375
armv7_pmnc_stop(void)376 static void armv7_pmnc_stop(void)
377 {
378 #ifdef DEBUG
379 armv7_pmnc_dump_regs();
380 #endif
381 armv7_stop_pmnc();
382 armv7_release_interrupts(irqs, ARRAY_SIZE(irqs));
383 }
384
armv7_pmnc_start(void)385 static int armv7_pmnc_start(void)
386 {
387 int ret;
388
389 #ifdef DEBUG
390 armv7_pmnc_dump_regs();
391 #endif
392 ret = armv7_request_interrupts(irqs, ARRAY_SIZE(irqs));
393 if (ret >= 0)
394 armv7_start_pmnc();
395
396 return ret;
397 }
398
armv7_detect_pmnc(void)399 static int armv7_detect_pmnc(void)
400 {
401 return 0;
402 }
403
404 struct op_arm_model_spec op_armv7_spec = {
405 .init = armv7_detect_pmnc,
406 .num_counters = 5,
407 .setup_ctrs = armv7_setup_pmnc,
408 .start = armv7_pmnc_start,
409 .stop = armv7_pmnc_stop,
410 .name = "arm/armv7",
411 };
412