arch/sparc/kernel/pcr.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /* pcr.c: Generic sparc64 performance counter infrastructure.
   3  *
   4  * Copyright (C) 2009 David S. Miller (davem@davemloft.net)
   5  */
   6 #include <linux/kernel.h>
   7 #include <linux/export.h>
   8 #include <linux/init.h>
   9 #include <linux/irq.h>
  10
  11 #include <linux/irq_work.h>
  12 #include <linux/ftrace.h>
  13
  14 #include <asm/pil.h>
  15 #include <asm/pcr.h>
  16 #include <asm/nmi.h>
  17 #include <asm/asi.h>
  18 #include <asm/spitfire.h>
  19
  20 /* This code is shared between various users of the performance
  21  * counters.  Users will be oprofile, pseudo-NMI watchdog, and the
  22  * perf_event support layer.
  23  */
  24
  25 /* Performance counter interrupts run unmasked at PIL level 15.
  26  * Therefore we can't do things like wakeups and other work
  27  * that expects IRQ disabling to be adhered to in locking etc.
  28  *
  29  * Therefore in such situations we defer the work by signalling
  30  * a lower level cpu IRQ.
  31  */
  32 void __irq_entry deferred_pcr_work_irq(int irq, struct pt_regs *regs)
  33 {
  34         struct pt_regs *old_regs;
  35
  36         clear_softint(1 << PIL_DEFERRED_PCR_WORK);
  37
  38         old_regs = set_irq_regs(regs);
  39         irq_enter();
  40 #ifdef CONFIG_IRQ_WORK
  41         irq_work_run();
  42 #endif
  43         irq_exit();
  44         set_irq_regs(old_regs);
  45 }
  46
  47 void arch_irq_work_raise(void)
  48 {
  49         set_softint(1 << PIL_DEFERRED_PCR_WORK);
  50 }
  51
  52 const struct pcr_ops *pcr_ops;
  53 EXPORT_SYMBOL_GPL(pcr_ops);
  54
  55 static u64 direct_pcr_read(unsigned long reg_num)
  56 {
  57         u64 val;
  58
  59         WARN_ON_ONCE(reg_num != 0);
  60         __asm__ __volatile__("rd %%pcr, %0" : "=r" (val));
  61         return val;
  62 }
  63
  64 static void direct_pcr_write(unsigned long reg_num, u64 val)
  65 {
  66         WARN_ON_ONCE(reg_num != 0);
  67         __asm__ __volatile__("wr %0, 0x0, %%pcr" : : "r" (val));
  68 }
  69
  70 static u64 direct_pic_read(unsigned long reg_num)
  71 {
  72         u64 val;
  73
  74         WARN_ON_ONCE(reg_num != 0);
  75         __asm__ __volatile__("rd %%pic, %0" : "=r" (val));
  76         return val;
  77 }
  78
  79 static void direct_pic_write(unsigned long reg_num, u64 val)
  80 {
  81         WARN_ON_ONCE(reg_num != 0);
  82
  83         /* Blackbird errata workaround.  See commentary in
  84          * arch/sparc64/kernel/smp.c:smp_percpu_timer_interrupt()
  85          * for more information.
  86          */
  87         __asm__ __volatile__("ba,pt     %%xcc, 99f\n\t"
  88                              " nop\n\t"
  89                              ".align    64\n"
  90                           "99:wr        %0, 0x0, %%pic\n\t"
  91                              "rd        %%pic, %%g0" : : "r" (val));
  92 }
  93
  94 static u64 direct_picl_value(unsigned int nmi_hz)
  95 {
  96         u32 delta = local_cpu_data().clock_tick / nmi_hz;
  97
  98         return ((u64)((0 - delta) & 0xffffffff)) << 32;
  99 }
 100
 101 static const struct pcr_ops direct_pcr_ops = {
 102         .read_pcr               = direct_pcr_read,
 103         .write_pcr              = direct_pcr_write,
 104         .read_pic               = direct_pic_read,
 105         .write_pic              = direct_pic_write,
 106         .nmi_picl_value         = direct_picl_value,
 107         .pcr_nmi_enable         = (PCR_PIC_PRIV | PCR_STRACE | PCR_UTRACE),
 108         .pcr_nmi_disable        = PCR_PIC_PRIV,
 109 };
 110
 111 static void n2_pcr_write(unsigned long reg_num, u64 val)
 112 {
 113         unsigned long ret;
 114
 115         WARN_ON_ONCE(reg_num != 0);
 116         if (val & PCR_N2_HTRACE) {
 117                 ret = sun4v_niagara2_setperf(HV_N2_PERF_SPARC_CTL, val);
 118                 if (ret != HV_EOK)
 119                         direct_pcr_write(reg_num, val);
 120         } else
 121                 direct_pcr_write(reg_num, val);
 122 }
 123
 124 static u64 n2_picl_value(unsigned int nmi_hz)
 125 {
 126         u32 delta = local_cpu_data().clock_tick / (nmi_hz << 2);
 127
 128         return ((u64)((0 - delta) & 0xffffffff)) << 32;
 129 }
 130
 131 static const struct pcr_ops n2_pcr_ops = {
 132         .read_pcr               = direct_pcr_read,
 133         .write_pcr              = n2_pcr_write,
 134         .read_pic               = direct_pic_read,
 135         .write_pic              = direct_pic_write,
 136         .nmi_picl_value         = n2_picl_value,
 137         .pcr_nmi_enable         = (PCR_PIC_PRIV | PCR_STRACE | PCR_UTRACE |
 138                                    PCR_N2_TOE_OV1 |
 139                                    (2 << PCR_N2_SL1_SHIFT) |
 140                                    (0xff << PCR_N2_MASK1_SHIFT)),
 141         .pcr_nmi_disable        = PCR_PIC_PRIV,
 142 };
 143
 144 static u64 n4_pcr_read(unsigned long reg_num)
 145 {
 146         unsigned long val;
 147
 148         (void) sun4v_vt_get_perfreg(reg_num, &val);
 149
 150         return val;
 151 }
 152
 153 static void n4_pcr_write(unsigned long reg_num, u64 val)
 154 {
 155         (void) sun4v_vt_set_perfreg(reg_num, val);
 156 }
 157
 158 static u64 n4_pic_read(unsigned long reg_num)
 159 {
 160         unsigned long val;
 161
 162         __asm__ __volatile__("ldxa [%1] %2, %0"
 163                              : "=r" (val)
 164                              : "r" (reg_num * 0x8UL), "i" (ASI_PIC));
 165
 166         return val;
 167 }
 168
 169 static void n4_pic_write(unsigned long reg_num, u64 val)
 170 {
 171         __asm__ __volatile__("stxa %0, [%1] %2"
 172                              : /* no outputs */
 173                              : "r" (val), "r" (reg_num * 0x8UL), "i" (ASI_PIC));
 174 }
 175
 176 static u64 n4_picl_value(unsigned int nmi_hz)
 177 {
 178         u32 delta = local_cpu_data().clock_tick / (nmi_hz << 2);
 179
 180         return ((u64)((0 - delta) & 0xffffffff));
 181 }
 182
 183 static const struct pcr_ops n4_pcr_ops = {
 184         .read_pcr               = n4_pcr_read,
 185         .write_pcr              = n4_pcr_write,
 186         .read_pic               = n4_pic_read,
 187         .write_pic              = n4_pic_write,
 188         .nmi_picl_value         = n4_picl_value,
 189         .pcr_nmi_enable         = (PCR_N4_PICNPT | PCR_N4_STRACE |
 190                                    PCR_N4_UTRACE | PCR_N4_TOE |
 191                                    (26 << PCR_N4_SL_SHIFT)),
 192         .pcr_nmi_disable        = PCR_N4_PICNPT,
 193 };
 194
 195 static u64 n5_pcr_read(unsigned long reg_num)
 196 {
 197         unsigned long val;
 198
 199         (void) sun4v_t5_get_perfreg(reg_num, &val);
 200
 201         return val;
 202 }
 203
 204 static void n5_pcr_write(unsigned long reg_num, u64 val)
 205 {
 206         (void) sun4v_t5_set_perfreg(reg_num, val);
 207 }
 208
 209 static const struct pcr_ops n5_pcr_ops = {
 210         .read_pcr               = n5_pcr_read,
 211         .write_pcr              = n5_pcr_write,
 212         .read_pic               = n4_pic_read,
 213         .write_pic              = n4_pic_write,
 214         .nmi_picl_value         = n4_picl_value,
 215         .pcr_nmi_enable         = (PCR_N4_PICNPT | PCR_N4_STRACE |
 216                                    PCR_N4_UTRACE | PCR_N4_TOE |
 217                                    (26 << PCR_N4_SL_SHIFT)),
 218         .pcr_nmi_disable        = PCR_N4_PICNPT,
 219 };
 220
 221 static u64 m7_pcr_read(unsigned long reg_num)
 222 {
 223         unsigned long val;
 224
 225         (void) sun4v_m7_get_perfreg(reg_num, &val);
 226
 227         return val;
 228 }
 229
 230 static void m7_pcr_write(unsigned long reg_num, u64 val)
 231 {
 232         (void) sun4v_m7_set_perfreg(reg_num, val);
 233 }
 234
 235 static const struct pcr_ops m7_pcr_ops = {
 236         .read_pcr               = m7_pcr_read,
 237         .write_pcr              = m7_pcr_write,
 238         .read_pic               = n4_pic_read,
 239         .write_pic              = n4_pic_write,
 240         .nmi_picl_value         = n4_picl_value,
 241         .pcr_nmi_enable         = (PCR_N4_PICNPT | PCR_N4_STRACE |
 242                                    PCR_N4_UTRACE | PCR_N4_TOE |
 243                                    (26 << PCR_N4_SL_SHIFT)),
 244         .pcr_nmi_disable        = PCR_N4_PICNPT,
 245 };
 246
 247 static unsigned long perf_hsvc_group;
 248 static unsigned long perf_hsvc_major;
 249 static unsigned long perf_hsvc_minor;
 250
 251 static int __init register_perf_hsvc(void)
 252 {
 253         unsigned long hverror;
 254
 255         if (tlb_type == hypervisor) {
 256                 switch (sun4v_chip_type) {
 257                 case SUN4V_CHIP_NIAGARA1:
 258                         perf_hsvc_group = HV_GRP_NIAG_PERF;
 259                         break;
 260
 261                 case SUN4V_CHIP_NIAGARA2:
 262                         perf_hsvc_group = HV_GRP_N2_CPU;
 263                         break;
 264
 265                 case SUN4V_CHIP_NIAGARA3:
 266                         perf_hsvc_group = HV_GRP_KT_CPU;
 267                         break;
 268
 269                 case SUN4V_CHIP_NIAGARA4:
 270                         perf_hsvc_group = HV_GRP_VT_CPU;
 271                         break;
 272
 273                 case SUN4V_CHIP_NIAGARA5:
 274                         perf_hsvc_group = HV_GRP_T5_CPU;
 275                         break;
 276
 277                 case SUN4V_CHIP_SPARC_M7:
 278                         perf_hsvc_group = HV_GRP_M7_PERF;
 279                         break;
 280
 281                 default:
 282                         return -ENODEV;
 283                 }
 284
 285
 286                 perf_hsvc_major = 1;
 287                 perf_hsvc_minor = 0;
 288                 hverror = sun4v_hvapi_register(perf_hsvc_group,
 289                                                perf_hsvc_major,
 290                                                &perf_hsvc_minor);
 291                 if (hverror) {
 292                         pr_err("perfmon: Could not register hvapi(0x%lx).\n",
 293                                hverror);
 294                         return -ENODEV;
 295                 }
 296         }
 297         return 0;
 298 }
 299
 300 static void __init unregister_perf_hsvc(void)
 301 {
 302         if (tlb_type != hypervisor)
 303                 return;
 304         sun4v_hvapi_unregister(perf_hsvc_group);
 305 }
 306
 307 static int __init setup_sun4v_pcr_ops(void)
 308 {
 309         int ret = 0;
 310
 311         switch (sun4v_chip_type) {
 312         case SUN4V_CHIP_NIAGARA1:
 313         case SUN4V_CHIP_NIAGARA2:
 314         case SUN4V_CHIP_NIAGARA3:
 315                 pcr_ops = &n2_pcr_ops;
 316                 break;
 317
 318         case SUN4V_CHIP_NIAGARA4:
 319                 pcr_ops = &n4_pcr_ops;
 320                 break;
 321
 322         case SUN4V_CHIP_NIAGARA5:
 323                 pcr_ops = &n5_pcr_ops;
 324                 break;
 325
 326         case SUN4V_CHIP_SPARC_M7:
 327                 pcr_ops = &m7_pcr_ops;
 328                 break;
 329
 330         default:
 331                 ret = -ENODEV;
 332                 break;
 333         }
 334
 335         return ret;
 336 }
 337
 338 int __init pcr_arch_init(void)
 339 {
 340         int err = register_perf_hsvc();
 341
 342         if (err)
 343                 return err;
 344
 345         switch (tlb_type) {
 346         case hypervisor:
 347                 err = setup_sun4v_pcr_ops();
 348                 if (err)
 349                         goto out_unregister;
 350                 break;
 351
 352         case cheetah:
 353         case cheetah_plus:
 354                 pcr_ops = &direct_pcr_ops;
 355                 break;
 356
 357         case spitfire:
 358                 /* UltraSPARC-I/II and derivatives lack a profile
 359                  * counter overflow interrupt so we can't make use of
 360                  * their hardware currently.
 361                  */
 362                 /* fallthrough */
 363         default:
 364                 err = -ENODEV;
 365                 goto out_unregister;
 366         }
 367
 368         return nmi_init();
 369
 370 out_unregister:
 371         unregister_perf_hsvc();
 372         return err;
 373 }