1// SPDX-License-Identifier: GPL-2.0-or-later 2/* 3 * 4 * Copyright (C) 2001, 2002, 2003 Broadcom Corporation 5 * Copyright (C) 2007 Ralf Baechle <ralf@linux-mips.org> 6 * Copyright (C) 2007 MIPS Technologies, Inc. 7 * written by Ralf Baechle <ralf@linux-mips.org> 8 */ 9 10#undef DEBUG 11 12#include <linux/device.h> 13#include <linux/module.h> 14#include <linux/kernel.h> 15#include <linux/types.h> 16#include <linux/init.h> 17#include <linux/interrupt.h> 18#include <linux/sched.h> 19#include <linux/vmalloc.h> 20#include <linux/fs.h> 21#include <linux/errno.h> 22#include <linux/wait.h> 23#include <asm/io.h> 24#include <asm/sibyte/sb1250.h> 25 26#ifdef CONFIG_SIBYTE_BCM1x80 27#include <asm/sibyte/bcm1480_regs.h> 28#include <asm/sibyte/bcm1480_scd.h> 29#include <asm/sibyte/bcm1480_int.h> 30#elif defined(CONFIG_SIBYTE_SB1250) || defined(CONFIG_SIBYTE_BCM112X) 31#include <asm/sibyte/sb1250_regs.h> 32#include <asm/sibyte/sb1250_scd.h> 33#include <asm/sibyte/sb1250_int.h> 34#else 35#error invalid SiByte UART configuration 36#endif 37 38#ifdef CONFIG_SIBYTE_BCM1x80 39#undef K_INT_TRACE_FREEZE 40#define K_INT_TRACE_FREEZE K_BCM1480_INT_TRACE_FREEZE 41#undef K_INT_PERF_CNT 42#define K_INT_PERF_CNT K_BCM1480_INT_PERF_CNT 43#endif 44 45#include <linux/uaccess.h> 46 47#define SBPROF_TB_MAJOR 240 48 49typedef u64 tb_sample_t[6*256]; 50 51enum open_status { 52 SB_CLOSED, 53 SB_OPENING, 54 SB_OPEN 55}; 56 57struct sbprof_tb { 58 wait_queue_head_t tb_sync; 59 wait_queue_head_t tb_read; 60 struct mutex lock; 61 enum open_status open; 62 tb_sample_t *sbprof_tbbuf; 63 int next_tb_sample; 64 65 volatile int tb_enable; 66 volatile int tb_armed; 67 68}; 69 70static struct sbprof_tb sbp; 71 72#define MAX_SAMPLE_BYTES (24*1024*1024) 73#define MAX_TBSAMPLE_BYTES (12*1024*1024) 74 75#define MAX_SAMPLES (MAX_SAMPLE_BYTES/sizeof(u_int32_t)) 76#define TB_SAMPLE_SIZE (sizeof(tb_sample_t)) 77#define MAX_TB_SAMPLES (MAX_TBSAMPLE_BYTES/TB_SAMPLE_SIZE) 78 79/* ioctls */ 80#define SBPROF_ZBSTART _IOW('s', 0, int) 81#define SBPROF_ZBSTOP _IOW('s', 1, int) 82#define SBPROF_ZBWAITFULL _IOW('s', 2, int) 83 84/* 85 * Routines for using 40-bit SCD cycle counter 86 * 87 * Client responsible for either handling interrupts or making sure 88 * the cycles counter never saturates, e.g., by doing 89 * zclk_timer_init(0) at least every 2^40 - 1 ZCLKs. 90 */ 91 92/* 93 * Configures SCD counter 0 to count ZCLKs starting from val; 94 * Configures SCD counters1,2,3 to count nothing. 95 * Must not be called while gathering ZBbus profiles. 96 */ 97 98#define zclk_timer_init(val) \ 99 __asm__ __volatile__ (".set push;" \ 100 ".set mips64;" \ 101 "la $8, 0xb00204c0;" /* SCD perf_cnt_cfg */ \ 102 "sd %0, 0x10($8);" /* write val to counter0 */ \ 103 "sd %1, 0($8);" /* config counter0 for zclks*/ \ 104 ".set pop" \ 105 : /* no outputs */ \ 106 /* enable, counter0 */ \ 107 : /* inputs */ "r"(val), "r" ((1ULL << 33) | 1ULL) \ 108 : /* modifies */ "$8" ) 109 110 111/* Reads SCD counter 0 and puts result in value 112 unsigned long long val; */ 113#define zclk_get(val) \ 114 __asm__ __volatile__ (".set push;" \ 115 ".set mips64;" \ 116 "la $8, 0xb00204c0;" /* SCD perf_cnt_cfg */ \ 117 "ld %0, 0x10($8);" /* write val to counter0 */ \ 118 ".set pop" \ 119 : /* outputs */ "=r"(val) \ 120 : /* inputs */ \ 121 : /* modifies */ "$8" ) 122 123#define DEVNAME "sb_tbprof" 124 125#define TB_FULL (sbp.next_tb_sample == MAX_TB_SAMPLES) 126 127/* 128 * Support for ZBbus sampling using the trace buffer 129 * 130 * We use the SCD performance counter interrupt, caused by a Zclk counter 131 * overflow, to trigger the start of tracing. 132 * 133 * We set the trace buffer to sample everything and freeze on 134 * overflow. 135 * 136 * We map the interrupt for trace_buffer_freeze to handle it on CPU 0. 137 * 138 */ 139 140static u64 tb_period; 141 142static void arm_tb(void) 143{ 144 u64 scdperfcnt; 145 u64 next = (1ULL << 40) - tb_period; 146 u64 tb_options = M_SCD_TRACE_CFG_FREEZE_FULL; 147 148 /* 149 * Generate an SCD_PERFCNT interrupt in TB_PERIOD Zclks to 150 * trigger start of trace. XXX vary sampling period 151 */ 152 __raw_writeq(0, IOADDR(A_SCD_PERF_CNT_1)); 153 scdperfcnt = __raw_readq(IOADDR(A_SCD_PERF_CNT_CFG)); 154 155 /* 156 * Unfortunately, in Pass 2 we must clear all counters to knock down 157 * a previous interrupt request. This means that bus profiling 158 * requires ALL of the SCD perf counters. 159 */ 160#ifdef CONFIG_SIBYTE_BCM1x80 161 __raw_writeq((scdperfcnt & ~M_SPC_CFG_SRC1) | 162 /* keep counters 0,2,3,4,5,6,7 as is */ 163 V_SPC_CFG_SRC1(1), /* counter 1 counts cycles */ 164 IOADDR(A_BCM1480_SCD_PERF_CNT_CFG0)); 165 __raw_writeq( 166 M_SPC_CFG_ENABLE | /* enable counting */ 167 M_SPC_CFG_CLEAR | /* clear all counters */ 168 V_SPC_CFG_SRC1(1), /* counter 1 counts cycles */ 169 IOADDR(A_BCM1480_SCD_PERF_CNT_CFG1)); 170#else 171 __raw_writeq((scdperfcnt & ~M_SPC_CFG_SRC1) | 172 /* keep counters 0,2,3 as is */ 173 M_SPC_CFG_ENABLE | /* enable counting */ 174 M_SPC_CFG_CLEAR | /* clear all counters */ 175 V_SPC_CFG_SRC1(1), /* counter 1 counts cycles */ 176 IOADDR(A_SCD_PERF_CNT_CFG)); 177#endif 178 __raw_writeq(next, IOADDR(A_SCD_PERF_CNT_1)); 179 /* Reset the trace buffer */ 180 __raw_writeq(M_SCD_TRACE_CFG_RESET, IOADDR(A_SCD_TRACE_CFG)); 181#if 0 && defined(M_SCD_TRACE_CFG_FORCECNT) 182 /* XXXKW may want to expose control to the data-collector */ 183 tb_options |= M_SCD_TRACE_CFG_FORCECNT; 184#endif 185 __raw_writeq(tb_options, IOADDR(A_SCD_TRACE_CFG)); 186 sbp.tb_armed = 1; 187} 188 189static irqreturn_t sbprof_tb_intr(int irq, void *dev_id) 190{ 191 int i; 192 193 pr_debug(DEVNAME ": tb_intr\n"); 194 195 if (sbp.next_tb_sample < MAX_TB_SAMPLES) { 196 /* XXX should use XKPHYS to make writes bypass L2 */ 197 u64 *p = sbp.sbprof_tbbuf[sbp.next_tb_sample++]; 198 /* Read out trace */ 199 __raw_writeq(M_SCD_TRACE_CFG_START_READ, 200 IOADDR(A_SCD_TRACE_CFG)); 201 __asm__ __volatile__ ("sync" : : : "memory"); 202 /* Loop runs backwards because bundles are read out in reverse order */ 203 for (i = 256 * 6; i > 0; i -= 6) { 204 /* Subscripts decrease to put bundle in the order */ 205 /* t0 lo, t0 hi, t1 lo, t1 hi, t2 lo, t2 hi */ 206 p[i - 1] = __raw_readq(IOADDR(A_SCD_TRACE_READ)); 207 /* read t2 hi */ 208 p[i - 2] = __raw_readq(IOADDR(A_SCD_TRACE_READ)); 209 /* read t2 lo */ 210 p[i - 3] = __raw_readq(IOADDR(A_SCD_TRACE_READ)); 211 /* read t1 hi */ 212 p[i - 4] = __raw_readq(IOADDR(A_SCD_TRACE_READ)); 213 /* read t1 lo */ 214 p[i - 5] = __raw_readq(IOADDR(A_SCD_TRACE_READ)); 215 /* read t0 hi */ 216 p[i - 6] = __raw_readq(IOADDR(A_SCD_TRACE_READ)); 217 /* read t0 lo */ 218 } 219 if (!sbp.tb_enable) { 220 pr_debug(DEVNAME ": tb_intr shutdown\n"); 221 __raw_writeq(M_SCD_TRACE_CFG_RESET, 222 IOADDR(A_SCD_TRACE_CFG)); 223 sbp.tb_armed = 0; 224 wake_up_interruptible(&sbp.tb_sync); 225 } else { 226 /* knock down current interrupt and get another one later */ 227 arm_tb(); 228 } 229 } else { 230 /* No more trace buffer samples */ 231 pr_debug(DEVNAME ": tb_intr full\n"); 232 __raw_writeq(M_SCD_TRACE_CFG_RESET, IOADDR(A_SCD_TRACE_CFG)); 233 sbp.tb_armed = 0; 234 if (!sbp.tb_enable) 235 wake_up_interruptible(&sbp.tb_sync); 236 wake_up_interruptible(&sbp.tb_read); 237 } 238 return IRQ_HANDLED; 239} 240 241static irqreturn_t sbprof_pc_intr(int irq, void *dev_id) 242{ 243 printk(DEVNAME ": unexpected pc_intr"); 244 return IRQ_NONE; 245} 246 247/* 248 * Requires: Already called zclk_timer_init with a value that won't 249 * saturate 40 bits. No subsequent use of SCD performance counters 250 * or trace buffer. 251 */ 252 253static int sbprof_zbprof_start(struct file *filp) 254{ 255 u64 scdperfcnt; 256 int err; 257 258 if (xchg(&sbp.tb_enable, 1)) 259 return -EBUSY; 260 261 pr_debug(DEVNAME ": starting\n"); 262 263 sbp.next_tb_sample = 0; 264 filp->f_pos = 0; 265 266 err = request_irq(K_INT_TRACE_FREEZE, sbprof_tb_intr, 0, 267 DEVNAME " trace freeze", &sbp); 268 if (err) 269 return -EBUSY; 270 271 /* Make sure there isn't a perf-cnt interrupt waiting */ 272 scdperfcnt = __raw_readq(IOADDR(A_SCD_PERF_CNT_CFG)); 273 /* Disable and clear counters, override SRC_1 */ 274 __raw_writeq((scdperfcnt & ~(M_SPC_CFG_SRC1 | M_SPC_CFG_ENABLE)) | 275 M_SPC_CFG_ENABLE | M_SPC_CFG_CLEAR | V_SPC_CFG_SRC1(1), 276 IOADDR(A_SCD_PERF_CNT_CFG)); 277 278 /* 279 * We grab this interrupt to prevent others from trying to use 280 * it, even though we don't want to service the interrupts 281 * (they only feed into the trace-on-interrupt mechanism) 282 */ 283 if (request_irq(K_INT_PERF_CNT, sbprof_pc_intr, 0, DEVNAME " scd perfcnt", &sbp)) { 284 free_irq(K_INT_TRACE_FREEZE, &sbp); 285 return -EBUSY; 286 } 287 288 /* 289 * I need the core to mask these, but the interrupt mapper to 290 * pass them through. I am exploiting my knowledge that 291 * cp0_status masks out IP[5]. krw 292 */ 293#ifdef CONFIG_SIBYTE_BCM1x80 294 __raw_writeq(K_BCM1480_INT_MAP_I3, 295 IOADDR(A_BCM1480_IMR_REGISTER(0, R_BCM1480_IMR_INTERRUPT_MAP_BASE_L) + 296 ((K_BCM1480_INT_PERF_CNT & 0x3f) << 3))); 297#else 298 __raw_writeq(K_INT_MAP_I3, 299 IOADDR(A_IMR_REGISTER(0, R_IMR_INTERRUPT_MAP_BASE) + 300 (K_INT_PERF_CNT << 3))); 301#endif 302 303 /* Initialize address traps */ 304 __raw_writeq(0, IOADDR(A_ADDR_TRAP_UP_0)); 305 __raw_writeq(0, IOADDR(A_ADDR_TRAP_UP_1)); 306 __raw_writeq(0, IOADDR(A_ADDR_TRAP_UP_2)); 307 __raw_writeq(0, IOADDR(A_ADDR_TRAP_UP_3)); 308 309 __raw_writeq(0, IOADDR(A_ADDR_TRAP_DOWN_0)); 310 __raw_writeq(0, IOADDR(A_ADDR_TRAP_DOWN_1)); 311 __raw_writeq(0, IOADDR(A_ADDR_TRAP_DOWN_2)); 312 __raw_writeq(0, IOADDR(A_ADDR_TRAP_DOWN_3)); 313 314 __raw_writeq(0, IOADDR(A_ADDR_TRAP_CFG_0)); 315 __raw_writeq(0, IOADDR(A_ADDR_TRAP_CFG_1)); 316 __raw_writeq(0, IOADDR(A_ADDR_TRAP_CFG_2)); 317 __raw_writeq(0, IOADDR(A_ADDR_TRAP_CFG_3)); 318 319 /* Initialize Trace Event 0-7 */ 320 /* when interrupt */ 321 __raw_writeq(M_SCD_TREVT_INTERRUPT, IOADDR(A_SCD_TRACE_EVENT_0)); 322 __raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_1)); 323 __raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_2)); 324 __raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_3)); 325 __raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_4)); 326 __raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_5)); 327 __raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_6)); 328 __raw_writeq(0, IOADDR(A_SCD_TRACE_EVENT_7)); 329 330 /* Initialize Trace Sequence 0-7 */ 331 /* Start on event 0 (interrupt) */ 332 __raw_writeq(V_SCD_TRSEQ_FUNC_START | 0x0fff, 333 IOADDR(A_SCD_TRACE_SEQUENCE_0)); 334 /* dsamp when d used | asamp when a used */ 335 __raw_writeq(M_SCD_TRSEQ_ASAMPLE | M_SCD_TRSEQ_DSAMPLE | 336 K_SCD_TRSEQ_TRIGGER_ALL, 337 IOADDR(A_SCD_TRACE_SEQUENCE_1)); 338 __raw_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_2)); 339 __raw_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_3)); 340 __raw_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_4)); 341 __raw_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_5)); 342 __raw_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_6)); 343 __raw_writeq(0, IOADDR(A_SCD_TRACE_SEQUENCE_7)); 344 345 /* Now indicate the PERF_CNT interrupt as a trace-relevant interrupt */ 346#ifdef CONFIG_SIBYTE_BCM1x80 347 __raw_writeq(1ULL << (K_BCM1480_INT_PERF_CNT & 0x3f), 348 IOADDR(A_BCM1480_IMR_REGISTER(0, R_BCM1480_IMR_INTERRUPT_TRACE_L))); 349#else 350 __raw_writeq(1ULL << K_INT_PERF_CNT, 351 IOADDR(A_IMR_REGISTER(0, R_IMR_INTERRUPT_TRACE))); 352#endif 353 arm_tb(); 354 355 pr_debug(DEVNAME ": done starting\n"); 356 357 return 0; 358} 359 360static int sbprof_zbprof_stop(void) 361{ 362 int err = 0; 363 364 pr_debug(DEVNAME ": stopping\n"); 365 366 if (sbp.tb_enable) { 367 /* 368 * XXXKW there is a window here where the intr handler may run, 369 * see the disable, and do the wake_up before this sleep 370 * happens. 371 */ 372 pr_debug(DEVNAME ": wait for disarm\n"); 373 err = wait_event_interruptible(sbp.tb_sync, !sbp.tb_armed); 374 pr_debug(DEVNAME ": disarm complete, stat %d\n", err); 375 376 if (err) 377 return err; 378 379 sbp.tb_enable = 0; 380 free_irq(K_INT_TRACE_FREEZE, &sbp); 381 free_irq(K_INT_PERF_CNT, &sbp); 382 } 383 384 pr_debug(DEVNAME ": done stopping\n"); 385 386 return err; 387} 388 389static int sbprof_tb_open(struct inode *inode, struct file *filp) 390{ 391 int minor; 392 393 minor = iminor(inode); 394 if (minor != 0) 395 return -ENODEV; 396 397 if (xchg(&sbp.open, SB_OPENING) != SB_CLOSED) 398 return -EBUSY; 399 400 memset(&sbp, 0, sizeof(struct sbprof_tb)); 401 sbp.sbprof_tbbuf = vzalloc(MAX_TBSAMPLE_BYTES); 402 if (!sbp.sbprof_tbbuf) { 403 sbp.open = SB_CLOSED; 404 wmb(); 405 return -ENOMEM; 406 } 407 408 init_waitqueue_head(&sbp.tb_sync); 409 init_waitqueue_head(&sbp.tb_read); 410 mutex_init(&sbp.lock); 411 412 sbp.open = SB_OPEN; 413 wmb(); 414 415 return 0; 416} 417 418static int sbprof_tb_release(struct inode *inode, struct file *filp) 419{ 420 int minor; 421 422 minor = iminor(inode); 423 if (minor != 0 || sbp.open != SB_CLOSED) 424 return -ENODEV; 425 426 mutex_lock(&sbp.lock); 427 428 if (sbp.tb_armed || sbp.tb_enable) 429 sbprof_zbprof_stop(); 430 431 vfree(sbp.sbprof_tbbuf); 432 sbp.open = SB_CLOSED; 433 wmb(); 434 435 mutex_unlock(&sbp.lock); 436 437 return 0; 438} 439 440static ssize_t sbprof_tb_read(struct file *filp, char __user *buf, 441 size_t size, loff_t *offp) 442{ 443 int cur_sample, sample_off, cur_count, sample_left; 444 char *src; 445 int count = 0; 446 char __user *dest = buf; 447 long cur_off = *offp; 448 449 if (!access_ok(buf, size)) 450 return -EFAULT; 451 452 mutex_lock(&sbp.lock); 453 454 count = 0; 455 cur_sample = cur_off / TB_SAMPLE_SIZE; 456 sample_off = cur_off % TB_SAMPLE_SIZE; 457 sample_left = TB_SAMPLE_SIZE - sample_off; 458 459 while (size && (cur_sample < sbp.next_tb_sample)) { 460 int err; 461 462 cur_count = size < sample_left ? size : sample_left; 463 src = (char *)(((long)sbp.sbprof_tbbuf[cur_sample])+sample_off); 464 err = __copy_to_user(dest, src, cur_count); 465 if (err) { 466 *offp = cur_off + cur_count - err; 467 mutex_unlock(&sbp.lock); 468 return err; 469 } 470 pr_debug(DEVNAME ": read from sample %d, %d bytes\n", 471 cur_sample, cur_count); 472 size -= cur_count; 473 sample_left -= cur_count; 474 if (!sample_left) { 475 cur_sample++; 476 sample_off = 0; 477 sample_left = TB_SAMPLE_SIZE; 478 } else { 479 sample_off += cur_count; 480 } 481 cur_off += cur_count; 482 dest += cur_count; 483 count += cur_count; 484 } 485 *offp = cur_off; 486 mutex_unlock(&sbp.lock); 487 488 return count; 489} 490 491static long sbprof_tb_ioctl(struct file *filp, 492 unsigned int command, 493 unsigned long arg) 494{ 495 int err = 0; 496 497 switch (command) { 498 case SBPROF_ZBSTART: 499 mutex_lock(&sbp.lock); 500 err = sbprof_zbprof_start(filp); 501 mutex_unlock(&sbp.lock); 502 break; 503 504 case SBPROF_ZBSTOP: 505 mutex_lock(&sbp.lock); 506 err = sbprof_zbprof_stop(); 507 mutex_unlock(&sbp.lock); 508 break; 509 510 case SBPROF_ZBWAITFULL: { 511 err = wait_event_interruptible(sbp.tb_read, TB_FULL); 512 if (err) 513 break; 514 515 err = put_user(TB_FULL, (int __user *) arg); 516 break; 517 } 518 519 default: 520 err = -EINVAL; 521 break; 522 } 523 524 return err; 525} 526 527static const struct file_operations sbprof_tb_fops = { 528 .owner = THIS_MODULE, 529 .open = sbprof_tb_open, 530 .release = sbprof_tb_release, 531 .read = sbprof_tb_read, 532 .unlocked_ioctl = sbprof_tb_ioctl, 533 .compat_ioctl = sbprof_tb_ioctl, 534 .mmap = NULL, 535 .llseek = default_llseek, 536}; 537 538static const struct class tb_class = { 539 .name = "sb_tracebuffer", 540}; 541static struct device *tb_dev; 542 543static int __init sbprof_tb_init(void) 544{ 545 struct device *dev; 546 int err; 547 548 if (register_chrdev(SBPROF_TB_MAJOR, DEVNAME, &sbprof_tb_fops)) { 549 printk(KERN_WARNING DEVNAME ": initialization failed (dev %d)\n", 550 SBPROF_TB_MAJOR); 551 return -EIO; 552 } 553 554 err = class_register(&tb_class); 555 if (err) 556 goto out_chrdev; 557 558 dev = device_create(&tb_class, NULL, MKDEV(SBPROF_TB_MAJOR, 0), NULL, "tb"); 559 if (IS_ERR(dev)) { 560 err = PTR_ERR(dev); 561 goto out_class; 562 } 563 tb_dev = dev; 564 565 sbp.open = SB_CLOSED; 566 wmb(); 567 tb_period = zbbus_mhz * 10000LL; 568 pr_info(DEVNAME ": initialized - tb_period = %lld\n", 569 (long long) tb_period); 570 return 0; 571 572out_class: 573 class_unregister(&tb_class); 574out_chrdev: 575 unregister_chrdev(SBPROF_TB_MAJOR, DEVNAME); 576 577 return err; 578} 579 580static void __exit sbprof_tb_cleanup(void) 581{ 582 device_destroy(&tb_class, MKDEV(SBPROF_TB_MAJOR, 0)); 583 unregister_chrdev(SBPROF_TB_MAJOR, DEVNAME); 584 class_unregister(&tb_class); 585} 586 587module_init(sbprof_tb_init); 588module_exit(sbprof_tb_cleanup); 589 590MODULE_ALIAS_CHARDEV_MAJOR(SBPROF_TB_MAJOR); 591MODULE_AUTHOR("Ralf Baechle <ralf@linux-mips.org>"); 592MODULE_LICENSE("GPL"); 593