xref: /openbmc/qemu/target/ppc/power8-pmu.c (revision 2f95279a) 
1 /*
2  * PMU emulation helpers for TCG IBM POWER chips
3  *
4  *  Copyright IBM Corp. 2021
5  *
6  * Authors:
7  *  Daniel Henrique Barboza      <danielhb413@gmail.com>
8  *
9  * This work is licensed under the terms of the GNU GPL, version 2 or later.
10  * See the COPYING file in the top-level directory.
11  */
12 
13 #include "qemu/osdep.h"
14 #include "cpu.h"
15 #include "helper_regs.h"
16 #include "exec/exec-all.h"
17 #include "exec/helper-proto.h"
18 #include "qemu/error-report.h"
19 #include "qemu/timer.h"
20 #include "hw/ppc/ppc.h"
21 #include "power8-pmu.h"
22 
23 #if defined(TARGET_PPC64) && !defined(CONFIG_USER_ONLY)
24 
25 static bool pmc_has_overflow_enabled(CPUPPCState *env, int sprn)
26 {
27     if (sprn == SPR_POWER_PMC1) {
28         return env->spr[SPR_POWER_MMCR0] & MMCR0_PMC1CE;
29     }
30 
31     return env->spr[SPR_POWER_MMCR0] & MMCR0_PMCjCE;
32 }
33 
34 /*
35  * Called after MMCR0 or MMCR1 changes to update pmc_ins_cnt and pmc_cyc_cnt.
36  * hflags must subsequently be updated.
37  */
38 static void pmu_update_summaries(CPUPPCState *env)
39 {
40     target_ulong mmcr0 = env->spr[SPR_POWER_MMCR0];
41     target_ulong mmcr1 = env->spr[SPR_POWER_MMCR1];
42     int ins_cnt = 0;
43     int cyc_cnt = 0;
44 
45     if (mmcr0 & MMCR0_FC) {
46         goto out;
47     }
48 
49     if (!(mmcr0 & MMCR0_FC14) && mmcr1 != 0) {
50         target_ulong sel;
51 
52         sel = extract64(mmcr1, MMCR1_PMC1EVT_EXTR, MMCR1_EVT_SIZE);
53         switch (sel) {
54         case 0x02:
55         case 0xfe:
56             ins_cnt |= 1 << 1;
57             break;
58         case 0x1e:
59         case 0xf0:
60             cyc_cnt |= 1 << 1;
61             break;
62         }
63 
64         sel = extract64(mmcr1, MMCR1_PMC2EVT_EXTR, MMCR1_EVT_SIZE);
65         ins_cnt |= (sel == 0x02) << 2;
66         cyc_cnt |= (sel == 0x1e) << 2;
67 
68         sel = extract64(mmcr1, MMCR1_PMC3EVT_EXTR, MMCR1_EVT_SIZE);
69         ins_cnt |= (sel == 0x02) << 3;
70         cyc_cnt |= (sel == 0x1e) << 3;
71 
72         sel = extract64(mmcr1, MMCR1_PMC4EVT_EXTR, MMCR1_EVT_SIZE);
73         ins_cnt |= ((sel == 0xfa) || (sel == 0x2)) << 4;
74         cyc_cnt |= (sel == 0x1e) << 4;
75     }
76 
77     ins_cnt |= !(mmcr0 & MMCR0_FC56) << 5;
78     cyc_cnt |= !(mmcr0 & MMCR0_FC56) << 6;
79 
80  out:
81     env->pmc_ins_cnt = ins_cnt;
82     env->pmc_cyc_cnt = cyc_cnt;
83 }
84 
85 static void hreg_bhrb_filter_update(CPUPPCState *env)
86 {
87     target_long ifm;
88 
89     if (!(env->spr[SPR_POWER_MMCR0] & MMCR0_PMAE)) {
90         /* disable recording to BHRB */
91         env->bhrb_filter = BHRB_TYPE_NORECORD;
92         return;
93     }
94 
95     ifm = (env->spr[SPR_POWER_MMCRA] & MMCRA_IFM_MASK) >> MMCRA_IFM_SHIFT;
96     switch (ifm) {
97     case 0:
98         /* record all branches */
99         env->bhrb_filter = -1;
100         break;
101     case 1:
102         /* only record calls (LK = 1) */
103         env->bhrb_filter = BHRB_TYPE_CALL;
104         break;
105     case 2:
106         /* only record indirect branches */
107         env->bhrb_filter = BHRB_TYPE_INDIRECT;
108         break;
109     case 3:
110         /* only record conditional branches */
111         env->bhrb_filter = BHRB_TYPE_COND;
112         break;
113     }
114 }
115 
116 void pmu_mmcr01a_updated(CPUPPCState *env)
117 {
118     PowerPCCPU *cpu = env_archcpu(env);
119 
120     pmu_update_summaries(env);
121     hreg_update_pmu_hflags(env);
122 
123     if (env->spr[SPR_POWER_MMCR0] & MMCR0_PMAO) {
124         ppc_set_irq(cpu, PPC_INTERRUPT_PERFM, 1);
125     } else {
126         ppc_set_irq(cpu, PPC_INTERRUPT_PERFM, 0);
127     }
128 
129     hreg_bhrb_filter_update(env);
130 
131     /*
132      * Should this update overflow timers (if mmcr0 is updated) so they
133      * get set in cpu_post_load?
134      */
135 }
136 
137 static bool pmu_increment_insns(CPUPPCState *env, uint32_t num_insns)
138 {
139     target_ulong mmcr0 = env->spr[SPR_POWER_MMCR0];
140     unsigned ins_cnt = env->pmc_ins_cnt;
141     bool overflow_triggered = false;
142     target_ulong tmp;
143 
144     if (ins_cnt & (1 << 1)) {
145         tmp = env->spr[SPR_POWER_PMC1];
146         tmp += num_insns;
147         if (tmp >= PMC_COUNTER_NEGATIVE_VAL && (mmcr0 & MMCR0_PMC1CE)) {
148             tmp = PMC_COUNTER_NEGATIVE_VAL;
149             overflow_triggered = true;
150         }
151         env->spr[SPR_POWER_PMC1] = tmp;
152     }
153 
154     if (ins_cnt & (1 << 2)) {
155         tmp = env->spr[SPR_POWER_PMC2];
156         tmp += num_insns;
157         if (tmp >= PMC_COUNTER_NEGATIVE_VAL && (mmcr0 & MMCR0_PMCjCE)) {
158             tmp = PMC_COUNTER_NEGATIVE_VAL;
159             overflow_triggered = true;
160         }
161         env->spr[SPR_POWER_PMC2] = tmp;
162     }
163 
164     if (ins_cnt & (1 << 3)) {
165         tmp = env->spr[SPR_POWER_PMC3];
166         tmp += num_insns;
167         if (tmp >= PMC_COUNTER_NEGATIVE_VAL && (mmcr0 & MMCR0_PMCjCE)) {
168             tmp = PMC_COUNTER_NEGATIVE_VAL;
169             overflow_triggered = true;
170         }
171         env->spr[SPR_POWER_PMC3] = tmp;
172     }
173 
174     if (ins_cnt & (1 << 4)) {
175         target_ulong mmcr1 = env->spr[SPR_POWER_MMCR1];
176         int sel = extract64(mmcr1, MMCR1_PMC4EVT_EXTR, MMCR1_EVT_SIZE);
177         if (sel == 0x02 || (env->spr[SPR_CTRL] & CTRL_RUN)) {
178             tmp = env->spr[SPR_POWER_PMC4];
179             tmp += num_insns;
180             if (tmp >= PMC_COUNTER_NEGATIVE_VAL && (mmcr0 & MMCR0_PMCjCE)) {
181                 tmp = PMC_COUNTER_NEGATIVE_VAL;
182                 overflow_triggered = true;
183             }
184             env->spr[SPR_POWER_PMC4] = tmp;
185         }
186     }
187 
188     if (ins_cnt & (1 << 5)) {
189         tmp = env->spr[SPR_POWER_PMC5];
190         tmp += num_insns;
191         if (tmp >= PMC_COUNTER_NEGATIVE_VAL && (mmcr0 & MMCR0_PMCjCE)) {
192             tmp = PMC_COUNTER_NEGATIVE_VAL;
193             overflow_triggered = true;
194         }
195         env->spr[SPR_POWER_PMC5] = tmp;
196     }
197 
198     return overflow_triggered;
199 }
200 
201 static void pmu_update_cycles(CPUPPCState *env)
202 {
203     uint64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
204     uint64_t time_delta = now - env->pmu_base_time;
205     int sprn, cyc_cnt = env->pmc_cyc_cnt;
206 
207     for (sprn = SPR_POWER_PMC1; sprn <= SPR_POWER_PMC6; sprn++) {
208         if (cyc_cnt & (1 << (sprn - SPR_POWER_PMC1 + 1))) {
209             /*
210              * The pseries and powernv clock runs at 1Ghz, meaning
211              * that 1 nanosec equals 1 cycle.
212              */
213             env->spr[sprn] += time_delta;
214         }
215     }
216 
217     /* Update base_time for future calculations */
218     env->pmu_base_time = now;
219 }
220 
221 /*
222  * Helper function to retrieve the cycle overflow timer of the
223  * 'sprn' counter.
224  */
225 static QEMUTimer *get_cyc_overflow_timer(CPUPPCState *env, int sprn)
226 {
227     return env->pmu_cyc_overflow_timers[sprn - SPR_POWER_PMC1];
228 }
229 
230 static void pmc_update_overflow_timer(CPUPPCState *env, int sprn)
231 {
232     QEMUTimer *pmc_overflow_timer = get_cyc_overflow_timer(env, sprn);
233     int64_t timeout;
234 
235     /*
236      * PMC5 does not have an overflow timer and this pointer
237      * will be NULL.
238      */
239     if (!pmc_overflow_timer) {
240         return;
241     }
242 
243     if (!(env->pmc_cyc_cnt & (1 << (sprn - SPR_POWER_PMC1 + 1))) ||
244         !pmc_has_overflow_enabled(env, sprn)) {
245         /* Overflow timer is not needed for this counter */
246         timer_del(pmc_overflow_timer);
247         return;
248     }
249 
250     if (env->spr[sprn] >= PMC_COUNTER_NEGATIVE_VAL) {
251         timeout = 0;
252     } else {
253         timeout = PMC_COUNTER_NEGATIVE_VAL - env->spr[sprn];
254     }
255 
256     /*
257      * Use timer_mod_anticipate() because an overflow timer might
258      * be already running for this PMC.
259      */
260     timer_mod_anticipate(pmc_overflow_timer, env->pmu_base_time + timeout);
261 }
262 
263 static void pmu_update_overflow_timers(CPUPPCState *env)
264 {
265     int sprn;
266 
267     /*
268      * Scroll through all PMCs and start counter overflow timers for
269      * PM_CYC events, if needed.
270      */
271     for (sprn = SPR_POWER_PMC1; sprn <= SPR_POWER_PMC6; sprn++) {
272         pmc_update_overflow_timer(env, sprn);
273     }
274 }
275 
276 static void pmu_delete_timers(CPUPPCState *env)
277 {
278     QEMUTimer *pmc_overflow_timer;
279     int sprn;
280 
281     for (sprn = SPR_POWER_PMC1; sprn <= SPR_POWER_PMC6; sprn++) {
282         pmc_overflow_timer = get_cyc_overflow_timer(env, sprn);
283 
284         if (pmc_overflow_timer) {
285             timer_del(pmc_overflow_timer);
286         }
287     }
288 }
289 
290 void helper_store_mmcr0(CPUPPCState *env, target_ulong value)
291 {
292     pmu_update_cycles(env);
293 
294     env->spr[SPR_POWER_MMCR0] = value;
295 
296     pmu_mmcr01a_updated(env);
297 
298     /* Update cycle overflow timers with the current MMCR0 state */
299     pmu_update_overflow_timers(env);
300 }
301 
302 void helper_store_mmcr1(CPUPPCState *env, uint64_t value)
303 {
304     pmu_update_cycles(env);
305 
306     env->spr[SPR_POWER_MMCR1] = value;
307 
308     pmu_mmcr01a_updated(env);
309 }
310 
311 void helper_store_mmcrA(CPUPPCState *env, uint64_t value)
312 {
313     env->spr[SPR_POWER_MMCRA] = value;
314 
315     pmu_mmcr01a_updated(env);
316 }
317 
318 target_ulong helper_read_pmc(CPUPPCState *env, uint32_t sprn)
319 {
320     pmu_update_cycles(env);
321 
322     return env->spr[sprn];
323 }
324 
325 void helper_store_pmc(CPUPPCState *env, uint32_t sprn, uint64_t value)
326 {
327     pmu_update_cycles(env);
328 
329     env->spr[sprn] = (uint32_t)value;
330 
331     pmc_update_overflow_timer(env, sprn);
332 }
333 
334 static void perfm_alert(PowerPCCPU *cpu)
335 {
336     CPUPPCState *env = &cpu->env;
337 
338     pmu_update_cycles(env);
339 
340     if (env->spr[SPR_POWER_MMCR0] & MMCR0_FCECE) {
341         env->spr[SPR_POWER_MMCR0] |= MMCR0_FC;
342 
343         /* Changing MMCR0_FC requires summaries and hflags update */
344         pmu_mmcr01a_updated(env);
345 
346         /*
347          * Delete all pending timers if we need to freeze
348          * the PMC. We'll restart them when the PMC starts
349          * running again.
350          */
351         pmu_delete_timers(env);
352     }
353 
354     if (env->spr[SPR_POWER_MMCR0] & MMCR0_PMAE) {
355         /* These MMCR0 bits do not require summaries or hflags update. */
356         env->spr[SPR_POWER_MMCR0] &= ~MMCR0_PMAE;
357         env->spr[SPR_POWER_MMCR0] |= MMCR0_PMAO;
358         ppc_set_irq(cpu, PPC_INTERRUPT_PERFM, 1);
359     }
360 
361     raise_ebb_perfm_exception(env);
362 }
363 
364 void helper_handle_pmc5_overflow(CPUPPCState *env)
365 {
366     env->spr[SPR_POWER_PMC5] = PMC_COUNTER_NEGATIVE_VAL;
367     perfm_alert(env_archcpu(env));
368 }
369 
370 /* This helper assumes that the PMC is running. */
371 void helper_insns_inc(CPUPPCState *env, uint32_t num_insns)
372 {
373     bool overflow_triggered;
374 
375     overflow_triggered = pmu_increment_insns(env, num_insns);
376     if (overflow_triggered) {
377         perfm_alert(env_archcpu(env));
378     }
379 }
380 
381 static void cpu_ppc_pmu_timer_cb(void *opaque)
382 {
383     PowerPCCPU *cpu = opaque;
384 
385     perfm_alert(cpu);
386 }
387 
388 void cpu_ppc_pmu_init(CPUPPCState *env)
389 {
390     PowerPCCPU *cpu = env_archcpu(env);
391     int i, sprn;
392 
393     for (sprn = SPR_POWER_PMC1; sprn <= SPR_POWER_PMC6; sprn++) {
394         if (sprn == SPR_POWER_PMC5) {
395             continue;
396         }
397 
398         i = sprn - SPR_POWER_PMC1;
399 
400         env->pmu_cyc_overflow_timers[i] = timer_new_ns(QEMU_CLOCK_VIRTUAL,
401                                                        &cpu_ppc_pmu_timer_cb,
402                                                        cpu);
403     }
404 }
405 #endif /* defined(TARGET_PPC64) && !defined(CONFIG_USER_ONLY) */
406