arch/powerpc/oprofile/op_model_power4.c

   1 /*
   2  * Copyright (C) 2004 Anton Blanchard <anton@au.ibm.com>, IBM
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version
   7  * 2 of the License, or (at your option) any later version.
   8  */
   9
  10 #include <linux/oprofile.h>
  11 #include <linux/init.h>
  12 #include <linux/smp.h>
  13 #include <asm/firmware.h>
  14 #include <asm/ptrace.h>
  15 #include <asm/system.h>
  16 #include <asm/processor.h>
  17 #include <asm/cputable.h>
  18 #include <asm/rtas.h>
  19 #include <asm/oprofile_impl.h>
  20 #include <asm/reg.h>
  21
  22 #define dbg(args...)
  23
  24 static unsigned long reset_value[OP_MAX_COUNTER];
  25
  26 static int oprofile_running;
  27
  28 /* mmcr values are set in power4_reg_setup, used in power4_cpu_setup */
  29 static u32 mmcr0_val;
  30 static u64 mmcr1_val;
  31 static u64 mmcra_val;
  32
  33 static void power4_reg_setup(struct op_counter_config *ctr,
  34                              struct op_system_config *sys,
  35                              int num_ctrs)
  36 {
  37         int i;
  38
  39         /*
  40          * The performance counter event settings are given in the mmcr0,
  41          * mmcr1 and mmcra values passed from the user in the
  42          * op_system_config structure (sys variable).
  43          */
  44         mmcr0_val = sys->mmcr0;
  45         mmcr1_val = sys->mmcr1;
  46         mmcra_val = sys->mmcra;
  47
  48         for (i = 0; i < cur_cpu_spec->num_pmcs; ++i)
  49                 reset_value[i] = 0x80000000UL - ctr[i].count;
  50
  51         /* setup user and kernel profiling */
  52         if (sys->enable_kernel)
  53                 mmcr0_val &= ~MMCR0_KERNEL_DISABLE;
  54         else
  55                 mmcr0_val |= MMCR0_KERNEL_DISABLE;
  56
  57         if (sys->enable_user)
  58                 mmcr0_val &= ~MMCR0_PROBLEM_DISABLE;
  59         else
  60                 mmcr0_val |= MMCR0_PROBLEM_DISABLE;
  61 }
  62
  63 extern void ppc64_enable_pmcs(void);
  64
  65 /*
  66  * Older CPUs require the MMCRA sample bit to be always set, but newer
  67  * CPUs only want it set for some groups. Eventually we will remove all
  68  * knowledge of this bit in the kernel, oprofile userspace should be
  69  * setting it when required.
  70  *
  71  * In order to keep current installations working we force the bit for
  72  * those older CPUs. Once everyone has updated their oprofile userspace we
  73  * can remove this hack.
  74  */
  75 static inline int mmcra_must_set_sample(void)
  76 {
  77         if (__is_processor(PV_POWER4) || __is_processor(PV_POWER4p) ||
  78             __is_processor(PV_970) || __is_processor(PV_970FX) ||
  79             __is_processor(PV_970MP))
  80                 return 1;
  81
  82         return 0;
  83 }
  84
  85 static void power4_cpu_setup(void *unused)
  86 {
  87         unsigned int mmcr0 = mmcr0_val;
  88         unsigned long mmcra = mmcra_val;
  89
  90         ppc64_enable_pmcs();
  91
  92         /* set the freeze bit */
  93         mmcr0 |= MMCR0_FC;
  94         mtspr(SPRN_MMCR0, mmcr0);
  95
  96         mmcr0 |= MMCR0_FCM1|MMCR0_PMXE|MMCR0_FCECE;
  97         mmcr0 |= MMCR0_PMC1CE|MMCR0_PMCjCE;
  98         mtspr(SPRN_MMCR0, mmcr0);
  99
 100         mtspr(SPRN_MMCR1, mmcr1_val);
 101
 102         if (mmcra_must_set_sample())
 103                 mmcra |= MMCRA_SAMPLE_ENABLE;
 104         mtspr(SPRN_MMCRA, mmcra);
 105
 106         dbg("setup on cpu %d, mmcr0 %lx\n", smp_processor_id(),
 107             mfspr(SPRN_MMCR0));
 108         dbg("setup on cpu %d, mmcr1 %lx\n", smp_processor_id(),
 109             mfspr(SPRN_MMCR1));
 110         dbg("setup on cpu %d, mmcra %lx\n", smp_processor_id(),
 111             mfspr(SPRN_MMCRA));
 112 }
 113
 114 static void power4_start(struct op_counter_config *ctr)
 115 {
 116         int i;
 117         unsigned int mmcr0;
 118
 119         /* set the PMM bit (see comment below) */
 120         mtmsrd(mfmsr() | MSR_PMM);
 121
 122         for (i = 0; i < cur_cpu_spec->num_pmcs; ++i) {
 123                 if (ctr[i].enabled) {
 124                         ctr_write(i, reset_value[i]);
 125                 } else {
 126                         ctr_write(i, 0);
 127                 }
 128         }
 129
 130         mmcr0 = mfspr(SPRN_MMCR0);
 131
 132         /*
 133          * We must clear the PMAO bit on some (GQ) chips. Just do it
 134          * all the time
 135          */
 136         mmcr0 &= ~MMCR0_PMAO;
 137
 138         /*
 139          * now clear the freeze bit, counting will not start until we
 140          * rfid from this excetion, because only at that point will
 141          * the PMM bit be cleared
 142          */
 143         mmcr0 &= ~MMCR0_FC;
 144         mtspr(SPRN_MMCR0, mmcr0);
 145
 146         oprofile_running = 1;
 147
 148         dbg("start on cpu %d, mmcr0 %x\n", smp_processor_id(), mmcr0);
 149 }
 150
 151 static void power4_stop(void)
 152 {
 153         unsigned int mmcr0;
 154
 155         /* freeze counters */
 156         mmcr0 = mfspr(SPRN_MMCR0);
 157         mmcr0 |= MMCR0_FC;
 158         mtspr(SPRN_MMCR0, mmcr0);
 159
 160         oprofile_running = 0;
 161
 162         dbg("stop on cpu %d, mmcr0 %x\n", smp_processor_id(), mmcr0);
 163
 164         mb();
 165 }
 166
 167 /* Fake functions used by canonicalize_pc */
 168 static void __attribute_used__ hypervisor_bucket(void)
 169 {
 170 }
 171
 172 static void __attribute_used__ rtas_bucket(void)
 173 {
 174 }
 175
 176 static void __attribute_used__ kernel_unknown_bucket(void)
 177 {
 178 }
 179
 180 /*
 181  * On GQ and newer the MMCRA stores the HV and PR bits at the time
 182  * the SIAR was sampled. We use that to work out if the SIAR was sampled in
 183  * the hypervisor, our exception vectors or RTAS.
 184  */
 185 static unsigned long get_pc(struct pt_regs *regs)
 186 {
 187         unsigned long pc = mfspr(SPRN_SIAR);
 188         unsigned long mmcra;
 189
 190         /* Cant do much about it */
 191         if (!cur_cpu_spec->oprofile_mmcra_sihv)
 192                 return pc;
 193
 194         mmcra = mfspr(SPRN_MMCRA);
 195
 196         /* Were we in the hypervisor? */
 197         if (firmware_has_feature(FW_FEATURE_LPAR) &&
 198             (mmcra & cur_cpu_spec->oprofile_mmcra_sihv))
 199                 /* function descriptor madness */
 200                 return *((unsigned long *)hypervisor_bucket);
 201
 202         /* We were in userspace, nothing to do */
 203         if (mmcra & cur_cpu_spec->oprofile_mmcra_sipr)
 204                 return pc;
 205
 206 #ifdef CONFIG_PPC_RTAS
 207         /* Were we in RTAS? */
 208         if (pc >= rtas.base && pc < (rtas.base + rtas.size))
 209                 /* function descriptor madness */
 210                 return *((unsigned long *)rtas_bucket);
 211 #endif
 212
 213         /* Were we in our exception vectors or SLB real mode miss handler? */
 214         if (pc < 0x1000000UL)
 215                 return (unsigned long)__va(pc);
 216
 217         /* Not sure where we were */
 218         if (!is_kernel_addr(pc))
 219                 /* function descriptor madness */
 220                 return *((unsigned long *)kernel_unknown_bucket);
 221
 222         return pc;
 223 }
 224
 225 static int get_kernel(unsigned long pc, unsigned long mmcra)
 226 {
 227         int is_kernel;
 228
 229         if (!cur_cpu_spec->oprofile_mmcra_sihv) {
 230                 is_kernel = is_kernel_addr(pc);
 231         } else {
 232                 is_kernel = ((mmcra & cur_cpu_spec->oprofile_mmcra_sipr) == 0);
 233         }
 234
 235         return is_kernel;
 236 }
 237
 238 static void power4_handle_interrupt(struct pt_regs *regs,
 239                                     struct op_counter_config *ctr)
 240 {
 241         unsigned long pc;
 242         int is_kernel;
 243         int val;
 244         int i;
 245         unsigned int mmcr0;
 246         unsigned long mmcra;
 247
 248         mmcra = mfspr(SPRN_MMCRA);
 249
 250         pc = get_pc(regs);
 251         is_kernel = get_kernel(pc, mmcra);
 252
 253         /* set the PMM bit (see comment below) */
 254         mtmsrd(mfmsr() | MSR_PMM);
 255
 256         for (i = 0; i < cur_cpu_spec->num_pmcs; ++i) {
 257                 val = ctr_read(i);
 258                 if (val < 0) {
 259                         if (oprofile_running && ctr[i].enabled) {
 260                                 oprofile_add_ext_sample(pc, regs, i, is_kernel);
 261                                 ctr_write(i, reset_value[i]);
 262                         } else {
 263                                 ctr_write(i, 0);
 264                         }
 265                 }
 266         }
 267
 268         mmcr0 = mfspr(SPRN_MMCR0);
 269
 270         /* reset the perfmon trigger */
 271         mmcr0 |= MMCR0_PMXE;
 272
 273         /*
 274          * We must clear the PMAO bit on some (GQ) chips. Just do it
 275          * all the time
 276          */
 277         mmcr0 &= ~MMCR0_PMAO;
 278
 279         /* Clear the appropriate bits in the MMCRA */
 280         mmcra &= ~cur_cpu_spec->oprofile_mmcra_clear;
 281         mtspr(SPRN_MMCRA, mmcra);
 282
 283         /*
 284          * now clear the freeze bit, counting will not start until we
 285          * rfid from this exception, because only at that point will
 286          * the PMM bit be cleared
 287          */
 288         mmcr0 &= ~MMCR0_FC;
 289         mtspr(SPRN_MMCR0, mmcr0);
 290 }
 291
 292 struct op_powerpc_model op_model_power4 = {
 293         .reg_setup              = power4_reg_setup,
 294         .cpu_setup              = power4_cpu_setup,
 295         .start                  = power4_start,
 296         .stop                   = power4_stop,
 297         .handle_interrupt       = power4_handle_interrupt,
 298 };