linux/arch/powerpc/perf/mpc7450-pmu.c
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   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
  37static 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 */
  77static 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
 134static 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
 143static 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
 150static int mpc7450_get_constraint(u64 event, unsigned long *maskp,
 151                                  unsigned long *valp, u64 event_config1 __maybe_unused)
 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
 186static 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 */
 208static 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
 222static 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 */
 244static const u8 classmap[N_CLASSES] = {
 245        0x3f, 0x0f, 0x0b, 0x03, 0
 246};
 247
 248/* Bit position and width of each PMCSEL field */
 249static const int pmcsel_shift[N_COUNTER] = {
 250        6,      0,      27,     22,     17,     11
 251};
 252static 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 */
 259static int mpc7450_compute_mmcr(u64 event[], int n_ev, unsigned int hwc[],
 260                                struct mmcr_regs *mmcr,
 261                                struct perf_event *pevents[],
 262                                u32 flags __maybe_unused)
 263{
 264        u8 event_index[N_CLASSES][N_COUNTER];
 265        int n_classevent[N_CLASSES];
 266        int i, j, class, tuse;
 267        u32 pmc_inuse = 0, pmc_avail;
 268        u32 mmcr0 = 0, mmcr1 = 0, mmcr2 = 0;
 269        u32 ev, pmc, thresh;
 270
 271        if (n_ev > N_COUNTER)
 272                return -1;
 273
 274        /* First pass: count usage in each class */
 275        for (i = 0; i < N_CLASSES; ++i)
 276                n_classevent[i] = 0;
 277        for (i = 0; i < n_ev; ++i) {
 278                class = mpc7450_classify_event(event[i]);
 279                if (class < 0)
 280                        return -1;
 281                j = n_classevent[class]++;
 282                event_index[class][j] = i;
 283        }
 284
 285        /* Second pass: allocate PMCs from most specific event to least */
 286        for (class = N_CLASSES - 1; class >= 0; --class) {
 287                for (i = 0; i < n_classevent[class]; ++i) {
 288                        ev = event[event_index[class][i]];
 289                        if (class == 4) {
 290                                pmc = (ev >> PM_PMC_SH) & PM_PMC_MSK;
 291                                if (pmc_inuse & (1 << (pmc - 1)))
 292                                        return -1;
 293                        } else {
 294                                /* Find a suitable PMC */
 295                                pmc_avail = classmap[class] & ~pmc_inuse;
 296                                if (!pmc_avail)
 297                                        return -1;
 298                                pmc = ffs(pmc_avail);
 299                        }
 300                        pmc_inuse |= 1 << (pmc - 1);
 301
 302                        tuse = mpc7450_threshold_use(ev);
 303                        if (tuse) {
 304                                thresh = (ev >> PM_THRESH_SH) & PM_THRESH_MSK;
 305                                mmcr0 |= thresh << 16;
 306                                if (tuse == 2 && (ev & PM_THRMULT_MSKS))
 307                                        mmcr2 = 0x80000000;
 308                        }
 309                        ev &= pmcsel_mask[pmc - 1];
 310                        ev <<= pmcsel_shift[pmc - 1];
 311                        if (pmc <= 2)
 312                                mmcr0 |= ev;
 313                        else
 314                                mmcr1 |= ev;
 315                        hwc[event_index[class][i]] = pmc - 1;
 316                }
 317        }
 318
 319        if (pmc_inuse & 1)
 320                mmcr0 |= MMCR0_PMC1CE;
 321        if (pmc_inuse & 0x3e)
 322                mmcr0 |= MMCR0_PMCnCE;
 323
 324        /* Return MMCRx values */
 325        mmcr->mmcr0 = mmcr0;
 326        mmcr->mmcr1 = mmcr1;
 327        mmcr->mmcr2 = mmcr2;
 328        /*
 329         * 32-bit doesn't have an MMCRA and uses SPRN_MMCR2 to define
 330         * SPRN_MMCRA. So assign mmcra of cpu_hw_events with `mmcr2`
 331         * value to ensure that any write to this SPRN_MMCRA will
 332         * use mmcr2 value.
 333         */
 334        mmcr->mmcra = mmcr2;
 335        return 0;
 336}
 337
 338/*
 339 * Disable counting by a PMC.
 340 * Note that the pmc argument is 0-based here, not 1-based.
 341 */
 342static void mpc7450_disable_pmc(unsigned int pmc, struct mmcr_regs *mmcr)
 343{
 344        if (pmc <= 1)
 345                mmcr->mmcr0 &= ~(pmcsel_mask[pmc] << pmcsel_shift[pmc]);
 346        else
 347                mmcr->mmcr1 &= ~(pmcsel_mask[pmc] << pmcsel_shift[pmc]);
 348}
 349
 350static int mpc7450_generic_events[] = {
 351        [PERF_COUNT_HW_CPU_CYCLES]              = 1,
 352        [PERF_COUNT_HW_INSTRUCTIONS]            = 2,
 353        [PERF_COUNT_HW_CACHE_MISSES]            = 0x217, /* PM_L1_DCACHE_MISS */
 354        [PERF_COUNT_HW_BRANCH_INSTRUCTIONS]     = 0x122, /* PM_BR_CMPL */
 355        [PERF_COUNT_HW_BRANCH_MISSES]           = 0x41c, /* PM_BR_MPRED */
 356};
 357
 358#define C(x)    PERF_COUNT_HW_CACHE_##x
 359
 360/*
 361 * Table of generalized cache-related events.
 362 * 0 means not supported, -1 means nonsensical, other values
 363 * are event codes.
 364 */
 365static u64 mpc7450_cache_events[C(MAX)][C(OP_MAX)][C(RESULT_MAX)] = {
 366        [C(L1D)] = {            /*      RESULT_ACCESS   RESULT_MISS */
 367                [C(OP_READ)] = {        0,              0x225   },
 368                [C(OP_WRITE)] = {       0,              0x227   },
 369                [C(OP_PREFETCH)] = {    0,              0       },
 370        },
 371        [C(L1I)] = {            /*      RESULT_ACCESS   RESULT_MISS */
 372                [C(OP_READ)] = {        0x129,          0x115   },
 373                [C(OP_WRITE)] = {       -1,             -1      },
 374                [C(OP_PREFETCH)] = {    0x634,          0       },
 375        },
 376        [C(LL)] = {             /*      RESULT_ACCESS   RESULT_MISS */
 377                [C(OP_READ)] = {        0,              0       },
 378                [C(OP_WRITE)] = {       0,              0       },
 379                [C(OP_PREFETCH)] = {    0,              0       },
 380        },
 381        [C(DTLB)] = {           /*      RESULT_ACCESS   RESULT_MISS */
 382                [C(OP_READ)] = {        0,              0x312   },
 383                [C(OP_WRITE)] = {       -1,             -1      },
 384                [C(OP_PREFETCH)] = {    -1,             -1      },
 385        },
 386        [C(ITLB)] = {           /*      RESULT_ACCESS   RESULT_MISS */
 387                [C(OP_READ)] = {        0,              0x223   },
 388                [C(OP_WRITE)] = {       -1,             -1      },
 389                [C(OP_PREFETCH)] = {    -1,             -1      },
 390        },
 391        [C(BPU)] = {            /*      RESULT_ACCESS   RESULT_MISS */
 392                [C(OP_READ)] = {        0x122,          0x41c   },
 393                [C(OP_WRITE)] = {       -1,             -1      },
 394                [C(OP_PREFETCH)] = {    -1,             -1      },
 395        },
 396        [C(NODE)] = {           /*      RESULT_ACCESS   RESULT_MISS */
 397                [C(OP_READ)] = {        -1,             -1      },
 398                [C(OP_WRITE)] = {       -1,             -1      },
 399                [C(OP_PREFETCH)] = {    -1,             -1      },
 400        },
 401};
 402
 403struct power_pmu mpc7450_pmu = {
 404        .name                   = "MPC7450 family",
 405        .n_counter              = N_COUNTER,
 406        .max_alternatives       = MAX_ALT,
 407        .add_fields             = 0x00111555ul,
 408        .test_adder             = 0x00301000ul,
 409        .compute_mmcr           = mpc7450_compute_mmcr,
 410        .get_constraint         = mpc7450_get_constraint,
 411        .get_alternatives       = mpc7450_get_alternatives,
 412        .disable_pmc            = mpc7450_disable_pmc,
 413        .n_generic              = ARRAY_SIZE(mpc7450_generic_events),
 414        .generic_events         = mpc7450_generic_events,
 415        .cache_events           = &mpc7450_cache_events,
 416};
 417
 418static int __init init_mpc7450_pmu(void)
 419{
 420        if (!cur_cpu_spec->oprofile_cpu_type ||
 421            strcmp(cur_cpu_spec->oprofile_cpu_type, "ppc/7450"))
 422                return -ENODEV;
 423
 424        return register_power_pmu(&mpc7450_pmu);
 425}
 426
 427early_initcall(init_mpc7450_pmu);
 428
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