arch/arm/oprofile/op_model_xscale.c

   1 /**
   2  * @file op_model_xscale.c
   3  * XScale Performance Monitor Driver
   4  *
   5  * @remark Copyright 2000-2004 Deepak Saxena <dsaxena@mvista.com>
   6  * @remark Copyright 2000-2004 MontaVista Software Inc
   7  * @remark Copyright 2004 Dave Jiang <dave.jiang@intel.com>
   8  * @remark Copyright 2004 Intel Corporation
   9  * @remark Copyright 2004 Zwane Mwaikambo <zwane@arm.linux.org.uk>
  10  * @remark Copyright 2004 OProfile Authors
  11  *
  12  * @remark Read the file COPYING
  13  *
  14  * @author Zwane Mwaikambo
  15  */
  16
  17 /* #define DEBUG */
  18 #include <linux/types.h>
  19 #include <linux/errno.h>
  20 #include <linux/sched.h>
  21 #include <linux/oprofile.h>
  22 #include <linux/interrupt.h>
  23 #include <linux/irq.h>
  24
  25 #include <asm/system.h>
  26
  27 #include "op_counter.h"
  28 #include "op_arm_model.h"
  29
  30 #define PMU_ENABLE      0x001   /* Enable counters */
  31 #define PMN_RESET       0x002   /* Reset event counters */
  32 #define CCNT_RESET      0x004   /* Reset clock counter */
  33 #define PMU_RESET       (CCNT_RESET | PMN_RESET)
  34 #define PMU_CNT64       0x008   /* Make CCNT count every 64th cycle */
  35
  36 /* TODO do runtime detection */
  37 #ifdef CONFIG_ARCH_IOP32X
  38 #define XSCALE_PMU_IRQ  IRQ_IOP32X_CORE_PMU
  39 #endif
  40 #ifdef CONFIG_ARCH_IOP33X
  41 #define XSCALE_PMU_IRQ  IRQ_IOP33X_CORE_PMU
  42 #endif
  43 #ifdef CONFIG_ARCH_PXA
  44 #define XSCALE_PMU_IRQ  IRQ_PMU
  45 #endif
  46
  47 /*
  48  * Different types of events that can be counted by the XScale PMU
  49  * as used by Oprofile userspace. Here primarily for documentation
  50  * purposes.
  51  */
  52
  53 #define EVT_ICACHE_MISS                 0x00
  54 #define EVT_ICACHE_NO_DELIVER           0x01
  55 #define EVT_DATA_STALL                  0x02
  56 #define EVT_ITLB_MISS                   0x03
  57 #define EVT_DTLB_MISS                   0x04
  58 #define EVT_BRANCH                      0x05
  59 #define EVT_BRANCH_MISS                 0x06
  60 #define EVT_INSTRUCTION                 0x07
  61 #define EVT_DCACHE_FULL_STALL           0x08
  62 #define EVT_DCACHE_FULL_STALL_CONTIG    0x09
  63 #define EVT_DCACHE_ACCESS               0x0A
  64 #define EVT_DCACHE_MISS                 0x0B
  65 #define EVT_DCACE_WRITE_BACK            0x0C
  66 #define EVT_PC_CHANGED                  0x0D
  67 #define EVT_BCU_REQUEST                 0x10
  68 #define EVT_BCU_FULL                    0x11
  69 #define EVT_BCU_DRAIN                   0x12
  70 #define EVT_BCU_ECC_NO_ELOG             0x14
  71 #define EVT_BCU_1_BIT_ERR               0x15
  72 #define EVT_RMW                         0x16
  73 /* EVT_CCNT is not hardware defined */
  74 #define EVT_CCNT                        0xFE
  75 #define EVT_UNUSED                      0xFF
  76
  77 struct pmu_counter {
  78         volatile unsigned long ovf;
  79         unsigned long reset_counter;
  80 };
  81
  82 enum { CCNT, PMN0, PMN1, PMN2, PMN3, MAX_COUNTERS };
  83
  84 static struct pmu_counter results[MAX_COUNTERS];
  85
  86 /*
  87  * There are two versions of the PMU in current XScale processors
  88  * with differing register layouts and number of performance counters.
  89  * e.g. IOP32x is xsc1 whilst IOP33x is xsc2.
  90  * We detect which register layout to use in xscale_detect_pmu()
  91  */
  92 enum { PMU_XSC1, PMU_XSC2 };
  93
  94 struct pmu_type {
  95         int id;
  96         char *name;
  97         int num_counters;
  98         unsigned int int_enable;
  99         unsigned int cnt_ovf[MAX_COUNTERS];
 100         unsigned int int_mask[MAX_COUNTERS];
 101 };
 102
 103 static struct pmu_type pmu_parms[] = {
 104         {
 105                 .id             = PMU_XSC1,
 106                 .name           = "arm/xscale1",
 107                 .num_counters   = 3,
 108                 .int_mask       = { [PMN0] = 0x10, [PMN1] = 0x20,
 109                                     [CCNT] = 0x40 },
 110                 .cnt_ovf        = { [CCNT] = 0x400, [PMN0] = 0x100,
 111                                     [PMN1] = 0x200},
 112         },
 113         {
 114                 .id             = PMU_XSC2,
 115                 .name           = "arm/xscale2",
 116                 .num_counters   = 5,
 117                 .int_mask       = { [CCNT] = 0x01, [PMN0] = 0x02,
 118                                     [PMN1] = 0x04, [PMN2] = 0x08,
 119                                     [PMN3] = 0x10 },
 120                 .cnt_ovf        = { [CCNT] = 0x01, [PMN0] = 0x02,
 121                                     [PMN1] = 0x04, [PMN2] = 0x08,
 122                                     [PMN3] = 0x10 },
 123         },
 124 };
 125
 126 static struct pmu_type *pmu;
 127
 128 static void write_pmnc(u32 val)
 129 {
 130         if (pmu->id == PMU_XSC1) {
 131                 /* upper 4bits and 7, 11 are write-as-0 */
 132                 val &= 0xffff77f;
 133                 __asm__ __volatile__ ("mcr p14, 0, %0, c0, c0, 0" : : "r" (val));
 134         } else {
 135                 /* bits 4-23 are write-as-0, 24-31 are write ignored */
 136                 val &= 0xf;
 137                 __asm__ __volatile__ ("mcr p14, 0, %0, c0, c1, 0" : : "r" (val));
 138         }
 139 }
 140
 141 static u32 read_pmnc(void)
 142 {
 143         u32 val;
 144
 145         if (pmu->id == PMU_XSC1)
 146                 __asm__ __volatile__ ("mrc p14, 0, %0, c0, c0, 0" : "=r" (val));
 147         else {
 148                 __asm__ __volatile__ ("mrc p14, 0, %0, c0, c1, 0" : "=r" (val));
 149                 /* bits 1-2 and 4-23 are read-unpredictable */
 150                 val &= 0xff000009;
 151         }
 152
 153         return val;
 154 }
 155
 156 static u32 __xsc1_read_counter(int counter)
 157 {
 158         u32 val = 0;
 159
 160         switch (counter) {
 161         case CCNT:
 162                 __asm__ __volatile__ ("mrc p14, 0, %0, c1, c0, 0" : "=r" (val));
 163                 break;
 164         case PMN0:
 165                 __asm__ __volatile__ ("mrc p14, 0, %0, c2, c0, 0" : "=r" (val));
 166                 break;
 167         case PMN1:
 168                 __asm__ __volatile__ ("mrc p14, 0, %0, c3, c0, 0" : "=r" (val));
 169                 break;
 170         }
 171         return val;
 172 }
 173
 174 static u32 __xsc2_read_counter(int counter)
 175 {
 176         u32 val = 0;
 177
 178         switch (counter) {
 179         case CCNT:
 180                 __asm__ __volatile__ ("mrc p14, 0, %0, c1, c1, 0" : "=r" (val));
 181                 break;
 182         case PMN0:
 183                 __asm__ __volatile__ ("mrc p14, 0, %0, c0, c2, 0" : "=r" (val));
 184                 break;
 185         case PMN1:
 186                 __asm__ __volatile__ ("mrc p14, 0, %0, c1, c2, 0" : "=r" (val));
 187                 break;
 188         case PMN2:
 189                 __asm__ __volatile__ ("mrc p14, 0, %0, c2, c2, 0" : "=r" (val));
 190                 break;
 191         case PMN3:
 192                 __asm__ __volatile__ ("mrc p14, 0, %0, c3, c2, 0" : "=r" (val));
 193                 break;
 194         }
 195         return val;
 196 }
 197
 198 static u32 read_counter(int counter)
 199 {
 200         u32 val;
 201
 202         if (pmu->id == PMU_XSC1)
 203                 val = __xsc1_read_counter(counter);
 204         else
 205                 val = __xsc2_read_counter(counter);
 206
 207         return val;
 208 }
 209
 210 static void __xsc1_write_counter(int counter, u32 val)
 211 {
 212         switch (counter) {
 213         case CCNT:
 214                 __asm__ __volatile__ ("mcr p14, 0, %0, c1, c0, 0" : : "r" (val));
 215                 break;
 216         case PMN0:
 217                 __asm__ __volatile__ ("mcr p14, 0, %0, c2, c0, 0" : : "r" (val));
 218                 break;
 219         case PMN1:
 220                 __asm__ __volatile__ ("mcr p14, 0, %0, c3, c0, 0" : : "r" (val));
 221                 break;
 222         }
 223 }
 224
 225 static void __xsc2_write_counter(int counter, u32 val)
 226 {
 227         switch (counter) {
 228         case CCNT:
 229                 __asm__ __volatile__ ("mcr p14, 0, %0, c1, c1, 0" : : "r" (val));
 230                 break;
 231         case PMN0:
 232                 __asm__ __volatile__ ("mcr p14, 0, %0, c0, c2, 0" : : "r" (val));
 233                 break;
 234         case PMN1:
 235                 __asm__ __volatile__ ("mcr p14, 0, %0, c1, c2, 0" : : "r" (val));
 236                 break;
 237         case PMN2:
 238                 __asm__ __volatile__ ("mcr p14, 0, %0, c2, c2, 0" : : "r" (val));
 239                 break;
 240         case PMN3:
 241                 __asm__ __volatile__ ("mcr p14, 0, %0, c3, c2, 0" : : "r" (val));
 242                 break;
 243         }
 244 }
 245
 246 static void write_counter(int counter, u32 val)
 247 {
 248         if (pmu->id == PMU_XSC1)
 249                 __xsc1_write_counter(counter, val);
 250         else
 251                 __xsc2_write_counter(counter, val);
 252 }
 253
 254 static int xscale_setup_ctrs(void)
 255 {
 256         u32 evtsel, pmnc;
 257         int i;
 258
 259         for (i = CCNT; i < MAX_COUNTERS; i++) {
 260                 if (counter_config[i].enabled)
 261                         continue;
 262
 263                 counter_config[i].event = EVT_UNUSED;
 264         }
 265
 266         switch (pmu->id) {
 267         case PMU_XSC1:
 268                 pmnc = (counter_config[PMN1].event << 20) | (counter_config[PMN0].event << 12);
 269                 pr_debug("xscale_setup_ctrs: pmnc: %#08x\n", pmnc);
 270                 write_pmnc(pmnc);
 271                 break;
 272
 273         case PMU_XSC2:
 274                 evtsel = counter_config[PMN0].event | (counter_config[PMN1].event << 8) |
 275                         (counter_config[PMN2].event << 16) | (counter_config[PMN3].event << 24);
 276
 277                 pr_debug("xscale_setup_ctrs: evtsel %#08x\n", evtsel);
 278                 __asm__ __volatile__ ("mcr p14, 0, %0, c8, c1, 0" : : "r" (evtsel));
 279                 break;
 280         }
 281
 282         for (i = CCNT; i < MAX_COUNTERS; i++) {
 283                 if (counter_config[i].event == EVT_UNUSED) {
 284                         counter_config[i].event = 0;
 285                         pmu->int_enable &= ~pmu->int_mask[i];
 286                         continue;
 287                 }
 288
 289                 results[i].reset_counter = counter_config[i].count;
 290                 write_counter(i, -(u32)counter_config[i].count);
 291                 pmu->int_enable |= pmu->int_mask[i];
 292                 pr_debug("xscale_setup_ctrs: counter%d %#08x from %#08lx\n", i,
 293                         read_counter(i), counter_config[i].count);
 294         }
 295
 296         return 0;
 297 }
 298
 299 static void inline __xsc1_check_ctrs(void)
 300 {
 301         int i;
 302         u32 pmnc = read_pmnc();
 303
 304         /* NOTE: there's an A stepping errata that states if an overflow */
 305         /*       bit already exists and another occurs, the previous     */
 306         /*       Overflow bit gets cleared. There's no workaround.       */
 307         /*       Fixed in B stepping or later                            */
 308
 309         /* Write the value back to clear the overflow flags. Overflow */
 310         /* flags remain in pmnc for use below */
 311         write_pmnc(pmnc & ~PMU_ENABLE);
 312
 313         for (i = CCNT; i <= PMN1; i++) {
 314                 if (!(pmu->int_mask[i] & pmu->int_enable))
 315                         continue;
 316
 317                 if (pmnc & pmu->cnt_ovf[i])
 318                         results[i].ovf++;
 319         }
 320 }
 321
 322 static void inline __xsc2_check_ctrs(void)
 323 {
 324         int i;
 325         u32 flag = 0, pmnc = read_pmnc();
 326
 327         pmnc &= ~PMU_ENABLE;
 328         write_pmnc(pmnc);
 329
 330         /* read overflow flag register */
 331         __asm__ __volatile__ ("mrc p14, 0, %0, c5, c1, 0" : "=r" (flag));
 332
 333         for (i = CCNT; i <= PMN3; i++) {
 334                 if (!(pmu->int_mask[i] & pmu->int_enable))
 335                         continue;
 336
 337                 if (flag & pmu->cnt_ovf[i])
 338                         results[i].ovf++;
 339         }
 340
 341         /* writeback clears overflow bits */
 342         __asm__ __volatile__ ("mcr p14, 0, %0, c5, c1, 0" : : "r" (flag));
 343 }
 344
 345 static irqreturn_t xscale_pmu_interrupt(int irq, void *arg)
 346 {
 347         int i;
 348         u32 pmnc;
 349
 350         if (pmu->id == PMU_XSC1)
 351                 __xsc1_check_ctrs();
 352         else
 353                 __xsc2_check_ctrs();
 354
 355         for (i = CCNT; i < MAX_COUNTERS; i++) {
 356                 if (!results[i].ovf)
 357                         continue;
 358
 359                 write_counter(i, -(u32)results[i].reset_counter);
 360                 oprofile_add_sample(get_irq_regs(), i);
 361                 results[i].ovf--;
 362         }
 363
 364         pmnc = read_pmnc() | PMU_ENABLE;
 365         write_pmnc(pmnc);
 366
 367         return IRQ_HANDLED;
 368 }
 369
 370 static void xscale_pmu_stop(void)
 371 {
 372         u32 pmnc = read_pmnc();
 373
 374         pmnc &= ~PMU_ENABLE;
 375         write_pmnc(pmnc);
 376
 377         free_irq(XSCALE_PMU_IRQ, results);
 378 }
 379
 380 static int xscale_pmu_start(void)
 381 {
 382         int ret;
 383         u32 pmnc = read_pmnc();
 384
 385         ret = request_irq(XSCALE_PMU_IRQ, xscale_pmu_interrupt, IRQF_DISABLED,
 386                         "XScale PMU", (void *)results);
 387
 388         if (ret < 0) {
 389                 printk(KERN_ERR "oprofile: unable to request IRQ%d for XScale PMU\n",
 390                         XSCALE_PMU_IRQ);
 391                 return ret;
 392         }
 393
 394         if (pmu->id == PMU_XSC1)
 395                 pmnc |= pmu->int_enable;
 396         else {
 397                 __asm__ __volatile__ ("mcr p14, 0, %0, c4, c1, 0" : : "r" (pmu->int_enable));
 398                 pmnc &= ~PMU_CNT64;
 399         }
 400
 401         pmnc |= PMU_ENABLE;
 402         write_pmnc(pmnc);
 403         pr_debug("xscale_pmu_start: pmnc: %#08x mask: %08x\n", pmnc, pmu->int_enable);
 404         return 0;
 405 }
 406
 407 static int xscale_detect_pmu(void)
 408 {
 409         int ret = 0;
 410         u32 id;
 411
 412         id = (read_cpuid(CPUID_ID) >> 13) & 0x7;
 413
 414         switch (id) {
 415         case 1:
 416                 pmu = &pmu_parms[PMU_XSC1];
 417                 break;
 418         case 2:
 419                 pmu = &pmu_parms[PMU_XSC2];
 420                 break;
 421         default:
 422                 ret = -ENODEV;
 423                 break;
 424         }
 425
 426         if (!ret) {
 427                 op_xscale_spec.name = pmu->name;
 428                 op_xscale_spec.num_counters = pmu->num_counters;
 429                 pr_debug("xscale_detect_pmu: detected %s PMU\n", pmu->name);
 430         }
 431
 432         return ret;
 433 }
 434
 435 struct op_arm_model_spec op_xscale_spec = {
 436         .init           = xscale_detect_pmu,
 437         .setup_ctrs     = xscale_setup_ctrs,
 438         .start          = xscale_pmu_start,
 439         .stop           = xscale_pmu_stop,
 440 };
 441