root/arch/powerpc/perf/mpc7450-pmu.c

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DEFINITIONS

This source file includes following definitions.
  1. mpc7450_classify_event
  2. mpc7450_threshold_use
  3. mpc7450_get_constraint
  4. find_alternative
  5. mpc7450_get_alternatives
  6. mpc7450_compute_mmcr
  7. mpc7450_disable_pmc
  8. init_mpc7450_pmu
   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Performance counter support for MPC7450-family processors.
   4  *
   5  * Copyright 2008-2009 Paul Mackerras, IBM Corporation.
   6  */
   7 #include <linux/string.h>
   8 #include <linux/perf_event.h>
   9 #include <asm/reg.h>
  10 #include <asm/cputable.h>
  11 
  12 #define N_COUNTER       6       /* Number of hardware counters */
  13 #define MAX_ALT         3       /* Maximum number of event alternative codes */
  14 
  15 /*
  16  * Bits in event code for MPC7450 family
  17  */
  18 #define PM_THRMULT_MSKS 0x40000
  19 #define PM_THRESH_SH    12
  20 #define PM_THRESH_MSK   0x3f
  21 #define PM_PMC_SH       8
  22 #define PM_PMC_MSK      7
  23 #define PM_PMCSEL_MSK   0x7f
  24 
  25 /*
  26  * Classify events according to how specific their PMC requirements are.
  27  * Result is:
  28  *      0: can go on any PMC
  29  *      1: can go on PMCs 1-4
  30  *      2: can go on PMCs 1,2,4
  31  *      3: can go on PMCs 1 or 2
  32  *      4: can only go on one PMC
  33  *      -1: event code is invalid
  34  */
  35 #define N_CLASSES       5
  36 
  37 static int mpc7450_classify_event(u32 event)
  38 {
  39         int pmc;
  40 
  41         pmc = (event >> PM_PMC_SH) & PM_PMC_MSK;
  42         if (pmc) {
  43                 if (pmc > N_COUNTER)
  44                         return -1;
  45                 return 4;
  46         }
  47         event &= PM_PMCSEL_MSK;
  48         if (event <= 1)
  49                 return 0;
  50         if (event <= 7)
  51                 return 1;
  52         if (event <= 13)
  53                 return 2;
  54         if (event <= 22)
  55                 return 3;
  56         return -1;
  57 }
  58 
  59 /*
  60  * Events using threshold and possible threshold scale:
  61  *      code    scale?  name
  62  *      11e     N       PM_INSTQ_EXCEED_CYC
  63  *      11f     N       PM_ALTV_IQ_EXCEED_CYC
  64  *      128     Y       PM_DTLB_SEARCH_EXCEED_CYC
  65  *      12b     Y       PM_LD_MISS_EXCEED_L1_CYC
  66  *      220     N       PM_CQ_EXCEED_CYC
  67  *      30c     N       PM_GPR_RB_EXCEED_CYC
  68  *      30d     ?       PM_FPR_IQ_EXCEED_CYC ?
  69  *      311     Y       PM_ITLB_SEARCH_EXCEED
  70  *      410     N       PM_GPR_IQ_EXCEED_CYC
  71  */
  72 
  73 /*
  74  * Return use of threshold and threshold scale bits:
  75  * 0 = uses neither, 1 = uses threshold, 2 = uses both
  76  */
  77 static int mpc7450_threshold_use(u32 event)
  78 {
  79         int pmc, sel;
  80 
  81         pmc = (event >> PM_PMC_SH) & PM_PMC_MSK;
  82         sel = event & PM_PMCSEL_MSK;
  83         switch (pmc) {
  84         case 1:
  85                 if (sel == 0x1e || sel == 0x1f)
  86                         return 1;
  87                 if (sel == 0x28 || sel == 0x2b)
  88                         return 2;
  89                 break;
  90         case 2:
  91                 if (sel == 0x20)
  92                         return 1;
  93                 break;
  94         case 3:
  95                 if (sel == 0xc || sel == 0xd)
  96                         return 1;
  97                 if (sel == 0x11)
  98                         return 2;
  99                 break;
 100         case 4:
 101                 if (sel == 0x10)
 102                         return 1;
 103                 break;
 104         }
 105         return 0;
 106 }
 107 
 108 /*
 109  * Layout of constraint bits:
 110  * 33222222222211111111110000000000
 111  * 10987654321098765432109876543210
 112  *  |<    ><  > < > < ><><><><><><>
 113  *  TS TV   G4   G3  G2P6P5P4P3P2P1
 114  *
 115  * P1 - P6
 116  *      0 - 11: Count of events needing PMC1 .. PMC6
 117  *
 118  * G2
 119  *      12 - 14: Count of events needing PMC1 or PMC2
 120  *
 121  * G3
 122  *      16 - 18: Count of events needing PMC1, PMC2 or PMC4
 123  *
 124  * G4
 125  *      20 - 23: Count of events needing PMC1, PMC2, PMC3 or PMC4
 126  *
 127  * TV
 128  *      24 - 29: Threshold value requested
 129  *
 130  * TS
 131  *      30: Threshold scale value requested
 132  */
 133 
 134 static u32 pmcbits[N_COUNTER][2] = {
 135         { 0x00844002, 0x00111001 },     /* PMC1 mask, value: P1,G2,G3,G4 */
 136         { 0x00844008, 0x00111004 },     /* PMC2: P2,G2,G3,G4 */
 137         { 0x00800020, 0x00100010 },     /* PMC3: P3,G4 */
 138         { 0x00840080, 0x00110040 },     /* PMC4: P4,G3,G4 */
 139         { 0x00000200, 0x00000100 },     /* PMC5: P5 */
 140         { 0x00000800, 0x00000400 }      /* PMC6: P6 */
 141 };
 142 
 143 static u32 classbits[N_CLASSES - 1][2] = {
 144         { 0x00000000, 0x00000000 },     /* class 0: no constraint */
 145         { 0x00800000, 0x00100000 },     /* class 1: G4 */
 146         { 0x00040000, 0x00010000 },     /* class 2: G3 */
 147         { 0x00004000, 0x00001000 },     /* class 3: G2 */
 148 };
 149 
 150 static int mpc7450_get_constraint(u64 event, unsigned long *maskp,
 151                                   unsigned long *valp)
 152 {
 153         int pmc, class;
 154         u32 mask, value;
 155         int thresh, tuse;
 156 
 157         class = mpc7450_classify_event(event);
 158         if (class < 0)
 159                 return -1;
 160         if (class == 4) {
 161                 pmc = ((unsigned int)event >> PM_PMC_SH) & PM_PMC_MSK;
 162                 mask  = pmcbits[pmc - 1][0];
 163                 value = pmcbits[pmc - 1][1];
 164         } else {
 165                 mask  = classbits[class][0];
 166                 value = classbits[class][1];
 167         }
 168 
 169         tuse = mpc7450_threshold_use(event);
 170         if (tuse) {
 171                 thresh = ((unsigned int)event >> PM_THRESH_SH) & PM_THRESH_MSK;
 172                 mask  |= 0x3f << 24;
 173                 value |= thresh << 24;
 174                 if (tuse == 2) {
 175                         mask |= 0x40000000;
 176                         if ((unsigned int)event & PM_THRMULT_MSKS)
 177                                 value |= 0x40000000;
 178                 }
 179         }
 180 
 181         *maskp = mask;
 182         *valp = value;
 183         return 0;
 184 }
 185 
 186 static const unsigned int event_alternatives[][MAX_ALT] = {
 187         { 0x217, 0x317 },               /* PM_L1_DCACHE_MISS */
 188         { 0x418, 0x50f, 0x60f },        /* PM_SNOOP_RETRY */
 189         { 0x502, 0x602 },               /* PM_L2_HIT */
 190         { 0x503, 0x603 },               /* PM_L3_HIT */
 191         { 0x504, 0x604 },               /* PM_L2_ICACHE_MISS */
 192         { 0x505, 0x605 },               /* PM_L3_ICACHE_MISS */
 193         { 0x506, 0x606 },               /* PM_L2_DCACHE_MISS */
 194         { 0x507, 0x607 },               /* PM_L3_DCACHE_MISS */
 195         { 0x50a, 0x623 },               /* PM_LD_HIT_L3 */
 196         { 0x50b, 0x624 },               /* PM_ST_HIT_L3 */
 197         { 0x50d, 0x60d },               /* PM_L2_TOUCH_HIT */
 198         { 0x50e, 0x60e },               /* PM_L3_TOUCH_HIT */
 199         { 0x512, 0x612 },               /* PM_INT_LOCAL */
 200         { 0x513, 0x61d },               /* PM_L2_MISS */
 201         { 0x514, 0x61e },               /* PM_L3_MISS */
 202 };
 203 
 204 /*
 205  * Scan the alternatives table for a match and return the
 206  * index into the alternatives table if found, else -1.
 207  */
 208 static int find_alternative(u32 event)
 209 {
 210         int i, j;
 211 
 212         for (i = 0; i < ARRAY_SIZE(event_alternatives); ++i) {
 213                 if (event < event_alternatives[i][0])
 214                         break;
 215                 for (j = 0; j < MAX_ALT && event_alternatives[i][j]; ++j)
 216                         if (event == event_alternatives[i][j])
 217                                 return i;
 218         }
 219         return -1;
 220 }
 221 
 222 static int mpc7450_get_alternatives(u64 event, unsigned int flags, u64 alt[])
 223 {
 224         int i, j, nalt = 1;
 225         u32 ae;
 226 
 227         alt[0] = event;
 228         nalt = 1;
 229         i = find_alternative((u32)event);
 230         if (i >= 0) {
 231                 for (j = 0; j < MAX_ALT; ++j) {
 232                         ae = event_alternatives[i][j];
 233                         if (ae && ae != (u32)event)
 234                                 alt[nalt++] = ae;
 235                 }
 236         }
 237         return nalt;
 238 }
 239 
 240 /*
 241  * Bitmaps of which PMCs each class can use for classes 0 - 3.
 242  * Bit i is set if PMC i+1 is usable.
 243  */
 244 static const u8 classmap[N_CLASSES] = {
 245         0x3f, 0x0f, 0x0b, 0x03, 0
 246 };
 247 
 248 /* Bit position and width of each PMCSEL field */
 249 static const int pmcsel_shift[N_COUNTER] = {
 250         6,      0,      27,     22,     17,     11
 251 };
 252 static const u32 pmcsel_mask[N_COUNTER] = {
 253         0x7f,   0x3f,   0x1f,   0x1f,   0x1f,   0x3f
 254 };
 255 
 256 /*
 257  * Compute MMCR0/1/2 values for a set of events.
 258  */
 259 static int mpc7450_compute_mmcr(u64 event[], int n_ev, unsigned int hwc[],
 260                                 unsigned long mmcr[],
 261                                 struct perf_event *pevents[])
 262 {
 263         u8 event_index[N_CLASSES][N_COUNTER];
 264         int n_classevent[N_CLASSES];
 265         int i, j, class, tuse;
 266         u32 pmc_inuse = 0, pmc_avail;
 267         u32 mmcr0 = 0, mmcr1 = 0, mmcr2 = 0;
 268         u32 ev, pmc, thresh;
 269 
 270         if (n_ev > N_COUNTER)
 271                 return -1;
 272 
 273         /* First pass: count usage in each class */
 274         for (i = 0; i < N_CLASSES; ++i)
 275                 n_classevent[i] = 0;
 276         for (i = 0; i < n_ev; ++i) {
 277                 class = mpc7450_classify_event(event[i]);
 278                 if (class < 0)
 279                         return -1;
 280                 j = n_classevent[class]++;
 281                 event_index[class][j] = i;
 282         }
 283 
 284         /* Second pass: allocate PMCs from most specific event to least */
 285         for (class = N_CLASSES - 1; class >= 0; --class) {
 286                 for (i = 0; i < n_classevent[class]; ++i) {
 287                         ev = event[event_index[class][i]];
 288                         if (class == 4) {
 289                                 pmc = (ev >> PM_PMC_SH) & PM_PMC_MSK;
 290                                 if (pmc_inuse & (1 << (pmc - 1)))
 291                                         return -1;
 292                         } else {
 293                                 /* Find a suitable PMC */
 294                                 pmc_avail = classmap[class] & ~pmc_inuse;
 295                                 if (!pmc_avail)
 296                                         return -1;
 297                                 pmc = ffs(pmc_avail);
 298                         }
 299                         pmc_inuse |= 1 << (pmc - 1);
 300 
 301                         tuse = mpc7450_threshold_use(ev);
 302                         if (tuse) {
 303                                 thresh = (ev >> PM_THRESH_SH) & PM_THRESH_MSK;
 304                                 mmcr0 |= thresh << 16;
 305                                 if (tuse == 2 && (ev & PM_THRMULT_MSKS))
 306                                         mmcr2 = 0x80000000;
 307                         }
 308                         ev &= pmcsel_mask[pmc - 1];
 309                         ev <<= pmcsel_shift[pmc - 1];
 310                         if (pmc <= 2)
 311                                 mmcr0 |= ev;
 312                         else
 313                                 mmcr1 |= ev;
 314                         hwc[event_index[class][i]] = pmc - 1;
 315                 }
 316         }
 317 
 318         if (pmc_inuse & 1)
 319                 mmcr0 |= MMCR0_PMC1CE;
 320         if (pmc_inuse & 0x3e)
 321                 mmcr0 |= MMCR0_PMCnCE;
 322 
 323         /* Return MMCRx values */
 324         mmcr[0] = mmcr0;
 325         mmcr[1] = mmcr1;
 326         mmcr[2] = mmcr2;
 327         return 0;
 328 }
 329 
 330 /*
 331  * Disable counting by a PMC.
 332  * Note that the pmc argument is 0-based here, not 1-based.
 333  */
 334 static void mpc7450_disable_pmc(unsigned int pmc, unsigned long mmcr[])
 335 {
 336         if (pmc <= 1)
 337                 mmcr[0] &= ~(pmcsel_mask[pmc] << pmcsel_shift[pmc]);
 338         else
 339                 mmcr[1] &= ~(pmcsel_mask[pmc] << pmcsel_shift[pmc]);
 340 }
 341 
 342 static int mpc7450_generic_events[] = {
 343         [PERF_COUNT_HW_CPU_CYCLES]              = 1,
 344         [PERF_COUNT_HW_INSTRUCTIONS]            = 2,
 345         [PERF_COUNT_HW_CACHE_MISSES]            = 0x217, /* PM_L1_DCACHE_MISS */
 346         [PERF_COUNT_HW_BRANCH_INSTRUCTIONS]     = 0x122, /* PM_BR_CMPL */
 347         [PERF_COUNT_HW_BRANCH_MISSES]           = 0x41c, /* PM_BR_MPRED */
 348 };
 349 
 350 #define C(x)    PERF_COUNT_HW_CACHE_##x
 351 
 352 /*
 353  * Table of generalized cache-related events.
 354  * 0 means not supported, -1 means nonsensical, other values
 355  * are event codes.
 356  */
 357 static int mpc7450_cache_events[C(MAX)][C(OP_MAX)][C(RESULT_MAX)] = {
 358         [C(L1D)] = {            /*      RESULT_ACCESS   RESULT_MISS */
 359                 [C(OP_READ)] = {        0,              0x225   },
 360                 [C(OP_WRITE)] = {       0,              0x227   },
 361                 [C(OP_PREFETCH)] = {    0,              0       },
 362         },
 363         [C(L1I)] = {            /*      RESULT_ACCESS   RESULT_MISS */
 364                 [C(OP_READ)] = {        0x129,          0x115   },
 365                 [C(OP_WRITE)] = {       -1,             -1      },
 366                 [C(OP_PREFETCH)] = {    0x634,          0       },
 367         },
 368         [C(LL)] = {             /*      RESULT_ACCESS   RESULT_MISS */
 369                 [C(OP_READ)] = {        0,              0       },
 370                 [C(OP_WRITE)] = {       0,              0       },
 371                 [C(OP_PREFETCH)] = {    0,              0       },
 372         },
 373         [C(DTLB)] = {           /*      RESULT_ACCESS   RESULT_MISS */
 374                 [C(OP_READ)] = {        0,              0x312   },
 375                 [C(OP_WRITE)] = {       -1,             -1      },
 376                 [C(OP_PREFETCH)] = {    -1,             -1      },
 377         },
 378         [C(ITLB)] = {           /*      RESULT_ACCESS   RESULT_MISS */
 379                 [C(OP_READ)] = {        0,              0x223   },
 380                 [C(OP_WRITE)] = {       -1,             -1      },
 381                 [C(OP_PREFETCH)] = {    -1,             -1      },
 382         },
 383         [C(BPU)] = {            /*      RESULT_ACCESS   RESULT_MISS */
 384                 [C(OP_READ)] = {        0x122,          0x41c   },
 385                 [C(OP_WRITE)] = {       -1,             -1      },
 386                 [C(OP_PREFETCH)] = {    -1,             -1      },
 387         },
 388         [C(NODE)] = {           /*      RESULT_ACCESS   RESULT_MISS */
 389                 [C(OP_READ)] = {        -1,             -1      },
 390                 [C(OP_WRITE)] = {       -1,             -1      },
 391                 [C(OP_PREFETCH)] = {    -1,             -1      },
 392         },
 393 };
 394 
 395 struct power_pmu mpc7450_pmu = {
 396         .name                   = "MPC7450 family",
 397         .n_counter              = N_COUNTER,
 398         .max_alternatives       = MAX_ALT,
 399         .add_fields             = 0x00111555ul,
 400         .test_adder             = 0x00301000ul,
 401         .compute_mmcr           = mpc7450_compute_mmcr,
 402         .get_constraint         = mpc7450_get_constraint,
 403         .get_alternatives       = mpc7450_get_alternatives,
 404         .disable_pmc            = mpc7450_disable_pmc,
 405         .n_generic              = ARRAY_SIZE(mpc7450_generic_events),
 406         .generic_events         = mpc7450_generic_events,
 407         .cache_events           = &mpc7450_cache_events,
 408 };
 409 
 410 static int __init init_mpc7450_pmu(void)
 411 {
 412         if (!cur_cpu_spec->oprofile_cpu_type ||
 413             strcmp(cur_cpu_spec->oprofile_cpu_type, "ppc/7450"))
 414                 return -ENODEV;
 415 
 416         return register_power_pmu(&mpc7450_pmu);
 417 }
 418 
 419 early_initcall(init_mpc7450_pmu);
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