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   1/*
   2 * Copyright © 2015-2016 Intel Corporation
   3 *
   4 * Permission is hereby granted, free of charge, to any person obtaining a
   5 * copy of this software and associated documentation files (the "Software"),
   6 * to deal in the Software without restriction, including without limitation
   7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8 * and/or sell copies of the Software, and to permit persons to whom the
   9 * Software is furnished to do so, subject to the following conditions:
  10 *
  11 * The above copyright notice and this permission notice (including the next
  12 * paragraph) shall be included in all copies or substantial portions of the
  13 * Software.
  14 *
  15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21 * IN THE SOFTWARE.
  22 *
  23 * Authors:
  24 *   Robert Bragg <robert@sixbynine.org>
  25 */
  26
  27
  28/**
  29 * DOC: i915 Perf Overview
  30 *
  31 * Gen graphics supports a large number of performance counters that can help
  32 * driver and application developers understand and optimize their use of the
  33 * GPU.
  34 *
  35 * This i915 perf interface enables userspace to configure and open a file
  36 * descriptor representing a stream of GPU metrics which can then be read() as
  37 * a stream of sample records.
  38 *
  39 * The interface is particularly suited to exposing buffered metrics that are
  40 * captured by DMA from the GPU, unsynchronized with and unrelated to the CPU.
  41 *
  42 * Streams representing a single context are accessible to applications with a
  43 * corresponding drm file descriptor, such that OpenGL can use the interface
  44 * without special privileges. Access to system-wide metrics requires root
  45 * privileges by default, unless changed via the dev.i915.perf_event_paranoid
  46 * sysctl option.
  47 *
  48 */
  49
  50/**
  51 * DOC: i915 Perf History and Comparison with Core Perf
  52 *
  53 * The interface was initially inspired by the core Perf infrastructure but
  54 * some notable differences are:
  55 *
  56 * i915 perf file descriptors represent a "stream" instead of an "event"; where
  57 * a perf event primarily corresponds to a single 64bit value, while a stream
  58 * might sample sets of tightly-coupled counters, depending on the
  59 * configuration.  For example the Gen OA unit isn't designed to support
  60 * orthogonal configurations of individual counters; it's configured for a set
  61 * of related counters. Samples for an i915 perf stream capturing OA metrics
  62 * will include a set of counter values packed in a compact HW specific format.
  63 * The OA unit supports a number of different packing formats which can be
  64 * selected by the user opening the stream. Perf has support for grouping
  65 * events, but each event in the group is configured, validated and
  66 * authenticated individually with separate system calls.
  67 *
  68 * i915 perf stream configurations are provided as an array of u64 (key,value)
  69 * pairs, instead of a fixed struct with multiple miscellaneous config members,
  70 * interleaved with event-type specific members.
  71 *
  72 * i915 perf doesn't support exposing metrics via an mmap'd circular buffer.
  73 * The supported metrics are being written to memory by the GPU unsynchronized
  74 * with the CPU, using HW specific packing formats for counter sets. Sometimes
  75 * the constraints on HW configuration require reports to be filtered before it
  76 * would be acceptable to expose them to unprivileged applications - to hide
  77 * the metrics of other processes/contexts. For these use cases a read() based
  78 * interface is a good fit, and provides an opportunity to filter data as it
  79 * gets copied from the GPU mapped buffers to userspace buffers.
  80 *
  81 *
  82 * Issues hit with first prototype based on Core Perf
  83 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  84 *
  85 * The first prototype of this driver was based on the core perf
  86 * infrastructure, and while we did make that mostly work, with some changes to
  87 * perf, we found we were breaking or working around too many assumptions baked
  88 * into perf's currently cpu centric design.
  89 *
  90 * In the end we didn't see a clear benefit to making perf's implementation and
  91 * interface more complex by changing design assumptions while we knew we still
  92 * wouldn't be able to use any existing perf based userspace tools.
  93 *
  94 * Also considering the Gen specific nature of the Observability hardware and
  95 * how userspace will sometimes need to combine i915 perf OA metrics with
  96 * side-band OA data captured via MI_REPORT_PERF_COUNT commands; we're
  97 * expecting the interface to be used by a platform specific userspace such as
  98 * OpenGL or tools. This is to say; we aren't inherently missing out on having
  99 * a standard vendor/architecture agnostic interface by not using perf.
 100 *
 101 *
 102 * For posterity, in case we might re-visit trying to adapt core perf to be
 103 * better suited to exposing i915 metrics these were the main pain points we
 104 * hit:
 105 *
 106 * - The perf based OA PMU driver broke some significant design assumptions:
 107 *
 108 *   Existing perf pmus are used for profiling work on a cpu and we were
 109 *   introducing the idea of _IS_DEVICE pmus with different security
 110 *   implications, the need to fake cpu-related data (such as user/kernel
 111 *   registers) to fit with perf's current design, and adding _DEVICE records
 112 *   as a way to forward device-specific status records.
 113 *
 114 *   The OA unit writes reports of counters into a circular buffer, without
 115 *   involvement from the CPU, making our PMU driver the first of a kind.
 116 *
 117 *   Given the way we were periodically forward data from the GPU-mapped, OA
 118 *   buffer to perf's buffer, those bursts of sample writes looked to perf like
 119 *   we were sampling too fast and so we had to subvert its throttling checks.
 120 *
 121 *   Perf supports groups of counters and allows those to be read via
 122 *   transactions internally but transactions currently seem designed to be
 123 *   explicitly initiated from the cpu (say in response to a userspace read())
 124 *   and while we could pull a report out of the OA buffer we can't
 125 *   trigger a report from the cpu on demand.
 126 *
 127 *   Related to being report based; the OA counters are configured in HW as a
 128 *   set while perf generally expects counter configurations to be orthogonal.
 129 *   Although counters can be associated with a group leader as they are
 130 *   opened, there's no clear precedent for being able to provide group-wide
 131 *   configuration attributes (for example we want to let userspace choose the
 132 *   OA unit report format used to capture all counters in a set, or specify a
 133 *   GPU context to filter metrics on). We avoided using perf's grouping
 134 *   feature and forwarded OA reports to userspace via perf's 'raw' sample
 135 *   field. This suited our userspace well considering how coupled the counters
 136 *   are when dealing with normalizing. It would be inconvenient to split
 137 *   counters up into separate events, only to require userspace to recombine
 138 *   them. For Mesa it's also convenient to be forwarded raw, periodic reports
 139 *   for combining with the side-band raw reports it captures using
 140 *   MI_REPORT_PERF_COUNT commands.
 141 *
 142 *   - As a side note on perf's grouping feature; there was also some concern
 143 *     that using PERF_FORMAT_GROUP as a way to pack together counter values
 144 *     would quite drastically inflate our sample sizes, which would likely
 145 *     lower the effective sampling resolutions we could use when the available
 146 *     memory bandwidth is limited.
 147 *
 148 *     With the OA unit's report formats, counters are packed together as 32
 149 *     or 40bit values, with the largest report size being 256 bytes.
 150 *
 151 *     PERF_FORMAT_GROUP values are 64bit, but there doesn't appear to be a
 152 *     documented ordering to the values, implying PERF_FORMAT_ID must also be
 153 *     used to add a 64bit ID before each value; giving 16 bytes per counter.
 154 *
 155 *   Related to counter orthogonality; we can't time share the OA unit, while
 156 *   event scheduling is a central design idea within perf for allowing
 157 *   userspace to open + enable more events than can be configured in HW at any
 158 *   one time.  The OA unit is not designed to allow re-configuration while in
 159 *   use. We can't reconfigure the OA unit without losing internal OA unit
 160 *   state which we can't access explicitly to save and restore. Reconfiguring
 161 *   the OA unit is also relatively slow, involving ~100 register writes. From
 162 *   userspace Mesa also depends on a stable OA configuration when emitting
 163 *   MI_REPORT_PERF_COUNT commands and importantly the OA unit can't be
 164 *   disabled while there are outstanding MI_RPC commands lest we hang the
 165 *   command streamer.
 166 *
 167 *   The contents of sample records aren't extensible by device drivers (i.e.
 168 *   the sample_type bits). As an example; Sourab Gupta had been looking to
 169 *   attach GPU timestamps to our OA samples. We were shoehorning OA reports
 170 *   into sample records by using the 'raw' field, but it's tricky to pack more
 171 *   than one thing into this field because events/core.c currently only lets a
 172 *   pmu give a single raw data pointer plus len which will be copied into the
 173 *   ring buffer. To include more than the OA report we'd have to copy the
 174 *   report into an intermediate larger buffer. I'd been considering allowing a
 175 *   vector of data+len values to be specified for copying the raw data, but
 176 *   it felt like a kludge to being using the raw field for this purpose.
 177 *
 178 * - It felt like our perf based PMU was making some technical compromises
 179 *   just for the sake of using perf:
 180 *
 181 *   perf_event_open() requires events to either relate to a pid or a specific
 182 *   cpu core, while our device pmu related to neither.  Events opened with a
 183 *   pid will be automatically enabled/disabled according to the scheduling of
 184 *   that process - so not appropriate for us. When an event is related to a
 185 *   cpu id, perf ensures pmu methods will be invoked via an inter process
 186 *   interrupt on that core. To avoid invasive changes our userspace opened OA
 187 *   perf events for a specific cpu. This was workable but it meant the
 188 *   majority of the OA driver ran in atomic context, including all OA report
 189 *   forwarding, which wasn't really necessary in our case and seems to make
 190 *   our locking requirements somewhat complex as we handled the interaction
 191 *   with the rest of the i915 driver.
 192 */
 193
 194#include <linux/anon_inodes.h>
 195#include <linux/sizes.h>
 196#include <linux/uuid.h>
 197
 198#include "gem/i915_gem_context.h"
 199#include "gem/i915_gem_internal.h"
 200#include "gt/intel_engine_pm.h"
 201#include "gt/intel_engine_regs.h"
 202#include "gt/intel_engine_user.h"
 203#include "gt/intel_execlists_submission.h"
 204#include "gt/intel_gpu_commands.h"
 205#include "gt/intel_gt.h"
 206#include "gt/intel_gt_clock_utils.h"
 207#include "gt/intel_gt_mcr.h"
 208#include "gt/intel_gt_regs.h"
 209#include "gt/intel_lrc.h"
 210#include "gt/intel_lrc_reg.h"
 211#include "gt/intel_ring.h"
 212#include "gt/uc/intel_guc_slpc.h"
 213
 214#include "i915_drv.h"
 215#include "i915_file_private.h"
 216#include "i915_perf.h"
 217#include "i915_perf_oa_regs.h"
 218#include "i915_reg.h"
 219
 220/* HW requires this to be a power of two, between 128k and 16M, though driver
 221 * is currently generally designed assuming the largest 16M size is used such
 222 * that the overflow cases are unlikely in normal operation.
 223 */
 224#define OA_BUFFER_SIZE		SZ_16M
 225
 226#define OA_TAKEN(tail, head)	((tail - head) & (OA_BUFFER_SIZE - 1))
 227
 228/**
 229 * DOC: OA Tail Pointer Race
 230 *
 231 * There's a HW race condition between OA unit tail pointer register updates and
 232 * writes to memory whereby the tail pointer can sometimes get ahead of what's
 233 * been written out to the OA buffer so far (in terms of what's visible to the
 234 * CPU).
 235 *
 236 * Although this can be observed explicitly while copying reports to userspace
 237 * by checking for a zeroed report-id field in tail reports, we want to account
 238 * for this earlier, as part of the oa_buffer_check_unlocked to avoid lots of
 239 * redundant read() attempts.
 240 *
 241 * We workaround this issue in oa_buffer_check_unlocked() by reading the reports
 242 * in the OA buffer, starting from the tail reported by the HW until we find a
 243 * report with its first 2 dwords not 0 meaning its previous report is
 244 * completely in memory and ready to be read. Those dwords are also set to 0
 245 * once read and the whole buffer is cleared upon OA buffer initialization. The
 246 * first dword is the reason for this report while the second is the timestamp,
 247 * making the chances of having those 2 fields at 0 fairly unlikely. A more
 248 * detailed explanation is available in oa_buffer_check_unlocked().
 249 *
 250 * Most of the implementation details for this workaround are in
 251 * oa_buffer_check_unlocked() and _append_oa_reports()
 252 *
 253 * Note for posterity: previously the driver used to define an effective tail
 254 * pointer that lagged the real pointer by a 'tail margin' measured in bytes
 255 * derived from %OA_TAIL_MARGIN_NSEC and the configured sampling frequency.
 256 * This was flawed considering that the OA unit may also automatically generate
 257 * non-periodic reports (such as on context switch) or the OA unit may be
 258 * enabled without any periodic sampling.
 259 */
 260#define OA_TAIL_MARGIN_NSEC	100000ULL
 261#define INVALID_TAIL_PTR	0xffffffff
 262
 263/* The default frequency for checking whether the OA unit has written new
 264 * reports to the circular OA buffer...
 265 */
 266#define DEFAULT_POLL_FREQUENCY_HZ 200
 267#define DEFAULT_POLL_PERIOD_NS (NSEC_PER_SEC / DEFAULT_POLL_FREQUENCY_HZ)
 268
 269/* for sysctl proc_dointvec_minmax of dev.i915.perf_stream_paranoid */
 270static u32 i915_perf_stream_paranoid = true;
 271
 272/* The maximum exponent the hardware accepts is 63 (essentially it selects one
 273 * of the 64bit timestamp bits to trigger reports from) but there's currently
 274 * no known use case for sampling as infrequently as once per 47 thousand years.
 275 *
 276 * Since the timestamps included in OA reports are only 32bits it seems
 277 * reasonable to limit the OA exponent where it's still possible to account for
 278 * overflow in OA report timestamps.
 279 */
 280#define OA_EXPONENT_MAX 31
 281
 282#define INVALID_CTX_ID 0xffffffff
 283
 284/* On Gen8+ automatically triggered OA reports include a 'reason' field... */
 285#define OAREPORT_REASON_MASK           0x3f
 286#define OAREPORT_REASON_MASK_EXTENDED  0x7f
 287#define OAREPORT_REASON_SHIFT          19
 288#define OAREPORT_REASON_TIMER          (1<<0)
 289#define OAREPORT_REASON_CTX_SWITCH     (1<<3)
 290#define OAREPORT_REASON_CLK_RATIO      (1<<5)
 291
 292#define HAS_MI_SET_PREDICATE(i915) (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 50))
 293
 294/* For sysctl proc_dointvec_minmax of i915_oa_max_sample_rate
 295 *
 296 * The highest sampling frequency we can theoretically program the OA unit
 297 * with is always half the timestamp frequency: E.g. 6.25Mhz for Haswell.
 298 *
 299 * Initialized just before we register the sysctl parameter.
 300 */
 301static int oa_sample_rate_hard_limit;
 302
 303/* Theoretically we can program the OA unit to sample every 160ns but don't
 304 * allow that by default unless root...
 305 *
 306 * The default threshold of 100000Hz is based on perf's similar
 307 * kernel.perf_event_max_sample_rate sysctl parameter.
 308 */
 309static u32 i915_oa_max_sample_rate = 100000;
 310
 311/* XXX: beware if future OA HW adds new report formats that the current
 312 * code assumes all reports have a power-of-two size and ~(size - 1) can
 313 * be used as a mask to align the OA tail pointer.
 314 */
 315static const struct i915_oa_format oa_formats[I915_OA_FORMAT_MAX] = {
 316	[I915_OA_FORMAT_A13]	    = { 0, 64 },
 317	[I915_OA_FORMAT_A29]	    = { 1, 128 },
 318	[I915_OA_FORMAT_A13_B8_C8]  = { 2, 128 },
 319	/* A29_B8_C8 Disallowed as 192 bytes doesn't factor into buffer size */
 320	[I915_OA_FORMAT_B4_C8]	    = { 4, 64 },
 321	[I915_OA_FORMAT_A45_B8_C8]  = { 5, 256 },
 322	[I915_OA_FORMAT_B4_C8_A16]  = { 6, 128 },
 323	[I915_OA_FORMAT_C4_B8]	    = { 7, 64 },
 324	[I915_OA_FORMAT_A12]		    = { 0, 64 },
 325	[I915_OA_FORMAT_A12_B8_C8]	    = { 2, 128 },
 326	[I915_OA_FORMAT_A32u40_A4u32_B8_C8] = { 5, 256 },
 327	[I915_OAR_FORMAT_A32u40_A4u32_B8_C8]    = { 5, 256 },
 328	[I915_OA_FORMAT_A24u40_A14u32_B8_C8]    = { 5, 256 },
 329};
 330
 331#define SAMPLE_OA_REPORT      (1<<0)
 332
 333/**
 334 * struct perf_open_properties - for validated properties given to open a stream
 335 * @sample_flags: `DRM_I915_PERF_PROP_SAMPLE_*` properties are tracked as flags
 336 * @single_context: Whether a single or all gpu contexts should be monitored
 337 * @hold_preemption: Whether the preemption is disabled for the filtered
 338 *                   context
 339 * @ctx_handle: A gem ctx handle for use with @single_context
 340 * @metrics_set: An ID for an OA unit metric set advertised via sysfs
 341 * @oa_format: An OA unit HW report format
 342 * @oa_periodic: Whether to enable periodic OA unit sampling
 343 * @oa_period_exponent: The OA unit sampling period is derived from this
 344 * @engine: The engine (typically rcs0) being monitored by the OA unit
 345 * @has_sseu: Whether @sseu was specified by userspace
 346 * @sseu: internal SSEU configuration computed either from the userspace
 347 *        specified configuration in the opening parameters or a default value
 348 *        (see get_default_sseu_config())
 349 * @poll_oa_period: The period in nanoseconds at which the CPU will check for OA
 350 * data availability
 351 *
 352 * As read_properties_unlocked() enumerates and validates the properties given
 353 * to open a stream of metrics the configuration is built up in the structure
 354 * which starts out zero initialized.
 355 */
 356struct perf_open_properties {
 357	u32 sample_flags;
 358
 359	u64 single_context:1;
 360	u64 hold_preemption:1;
 361	u64 ctx_handle;
 362
 363	/* OA sampling state */
 364	int metrics_set;
 365	int oa_format;
 366	bool oa_periodic;
 367	int oa_period_exponent;
 368
 369	struct intel_engine_cs *engine;
 370
 371	bool has_sseu;
 372	struct intel_sseu sseu;
 373
 374	u64 poll_oa_period;
 375};
 376
 377struct i915_oa_config_bo {
 378	struct llist_node node;
 379
 380	struct i915_oa_config *oa_config;
 381	struct i915_vma *vma;
 382};
 383
 384static struct ctl_table_header *sysctl_header;
 385
 386static enum hrtimer_restart oa_poll_check_timer_cb(struct hrtimer *hrtimer);
 387
 388void i915_oa_config_release(struct kref *ref)
 389{
 390	struct i915_oa_config *oa_config =
 391		container_of(ref, typeof(*oa_config), ref);
 392
 393	kfree(oa_config->flex_regs);
 394	kfree(oa_config->b_counter_regs);
 395	kfree(oa_config->mux_regs);
 396
 397	kfree_rcu(oa_config, rcu);
 398}
 399
 400struct i915_oa_config *
 401i915_perf_get_oa_config(struct i915_perf *perf, int metrics_set)
 402{
 403	struct i915_oa_config *oa_config;
 404
 405	rcu_read_lock();
 406	oa_config = idr_find(&perf->metrics_idr, metrics_set);
 407	if (oa_config)
 408		oa_config = i915_oa_config_get(oa_config);
 409	rcu_read_unlock();
 410
 411	return oa_config;
 412}
 413
 414static void free_oa_config_bo(struct i915_oa_config_bo *oa_bo)
 415{
 416	i915_oa_config_put(oa_bo->oa_config);
 417	i915_vma_put(oa_bo->vma);
 418	kfree(oa_bo);
 419}
 420
 421static u32 gen12_oa_hw_tail_read(struct i915_perf_stream *stream)
 422{
 423	struct intel_uncore *uncore = stream->uncore;
 424
 425	return intel_uncore_read(uncore, GEN12_OAG_OATAILPTR) &
 426	       GEN12_OAG_OATAILPTR_MASK;
 427}
 428
 429static u32 gen8_oa_hw_tail_read(struct i915_perf_stream *stream)
 430{
 431	struct intel_uncore *uncore = stream->uncore;
 432
 433	return intel_uncore_read(uncore, GEN8_OATAILPTR) & GEN8_OATAILPTR_MASK;
 434}
 435
 436static u32 gen7_oa_hw_tail_read(struct i915_perf_stream *stream)
 437{
 438	struct intel_uncore *uncore = stream->uncore;
 439	u32 oastatus1 = intel_uncore_read(uncore, GEN7_OASTATUS1);
 440
 441	return oastatus1 & GEN7_OASTATUS1_TAIL_MASK;
 442}
 443
 444/**
 445 * oa_buffer_check_unlocked - check for data and update tail ptr state
 446 * @stream: i915 stream instance
 447 *
 448 * This is either called via fops (for blocking reads in user ctx) or the poll
 449 * check hrtimer (atomic ctx) to check the OA buffer tail pointer and check
 450 * if there is data available for userspace to read.
 451 *
 452 * This function is central to providing a workaround for the OA unit tail
 453 * pointer having a race with respect to what data is visible to the CPU.
 454 * It is responsible for reading tail pointers from the hardware and giving
 455 * the pointers time to 'age' before they are made available for reading.
 456 * (See description of OA_TAIL_MARGIN_NSEC above for further details.)
 457 *
 458 * Besides returning true when there is data available to read() this function
 459 * also updates the tail, aging_tail and aging_timestamp in the oa_buffer
 460 * object.
 461 *
 462 * Note: It's safe to read OA config state here unlocked, assuming that this is
 463 * only called while the stream is enabled, while the global OA configuration
 464 * can't be modified.
 465 *
 466 * Returns: %true if the OA buffer contains data, else %false
 467 */
 468static bool oa_buffer_check_unlocked(struct i915_perf_stream *stream)
 469{
 470	u32 gtt_offset = i915_ggtt_offset(stream->oa_buffer.vma);
 471	int report_size = stream->oa_buffer.format->size;
 472	unsigned long flags;
 473	bool pollin;
 474	u32 hw_tail;
 475	u64 now;
 476
 477	/* We have to consider the (unlikely) possibility that read() errors
 478	 * could result in an OA buffer reset which might reset the head and
 479	 * tail state.
 480	 */
 481	spin_lock_irqsave(&stream->oa_buffer.ptr_lock, flags);
 482
 483	hw_tail = stream->perf->ops.oa_hw_tail_read(stream);
 484
 485	/* The tail pointer increases in 64 byte increments,
 486	 * not in report_size steps...
 487	 */
 488	hw_tail &= ~(report_size - 1);
 489
 490	now = ktime_get_mono_fast_ns();
 491
 492	if (hw_tail == stream->oa_buffer.aging_tail &&
 493	    (now - stream->oa_buffer.aging_timestamp) > OA_TAIL_MARGIN_NSEC) {
 494		/* If the HW tail hasn't move since the last check and the HW
 495		 * tail has been aging for long enough, declare it the new
 496		 * tail.
 497		 */
 498		stream->oa_buffer.tail = stream->oa_buffer.aging_tail;
 499	} else {
 500		u32 head, tail, aged_tail;
 501
 502		/* NB: The head we observe here might effectively be a little
 503		 * out of date. If a read() is in progress, the head could be
 504		 * anywhere between this head and stream->oa_buffer.tail.
 505		 */
 506		head = stream->oa_buffer.head - gtt_offset;
 507		aged_tail = stream->oa_buffer.tail - gtt_offset;
 508
 509		hw_tail -= gtt_offset;
 510		tail = hw_tail;
 511
 512		/* Walk the stream backward until we find a report with dword 0
 513		 * & 1 not at 0. Since the circular buffer pointers progress by
 514		 * increments of 64 bytes and that reports can be up to 256
 515		 * bytes long, we can't tell whether a report has fully landed
 516		 * in memory before the first 2 dwords of the following report
 517		 * have effectively landed.
 518		 *
 519		 * This is assuming that the writes of the OA unit land in
 520		 * memory in the order they were written to.
 521		 * If not : (╯°□°)╯︵ ┻━┻
 522		 */
 523		while (OA_TAKEN(tail, aged_tail) >= report_size) {
 524			u32 *report32 = (void *)(stream->oa_buffer.vaddr + tail);
 525
 526			if (report32[0] != 0 || report32[1] != 0)
 527				break;
 528
 529			tail = (tail - report_size) & (OA_BUFFER_SIZE - 1);
 530		}
 531
 532		if (OA_TAKEN(hw_tail, tail) > report_size &&
 533		    __ratelimit(&stream->perf->tail_pointer_race))
 534			drm_notice(&stream->uncore->i915->drm,
 535				   "unlanded report(s) head=0x%x tail=0x%x hw_tail=0x%x\n",
 536				   head, tail, hw_tail);
 537
 538		stream->oa_buffer.tail = gtt_offset + tail;
 539		stream->oa_buffer.aging_tail = gtt_offset + hw_tail;
 540		stream->oa_buffer.aging_timestamp = now;
 541	}
 542
 543	pollin = OA_TAKEN(stream->oa_buffer.tail - gtt_offset,
 544			  stream->oa_buffer.head - gtt_offset) >= report_size;
 545
 546	spin_unlock_irqrestore(&stream->oa_buffer.ptr_lock, flags);
 547
 548	return pollin;
 549}
 550
 551/**
 552 * append_oa_status - Appends a status record to a userspace read() buffer.
 553 * @stream: An i915-perf stream opened for OA metrics
 554 * @buf: destination buffer given by userspace
 555 * @count: the number of bytes userspace wants to read
 556 * @offset: (inout): the current position for writing into @buf
 557 * @type: The kind of status to report to userspace
 558 *
 559 * Writes a status record (such as `DRM_I915_PERF_RECORD_OA_REPORT_LOST`)
 560 * into the userspace read() buffer.
 561 *
 562 * The @buf @offset will only be updated on success.
 563 *
 564 * Returns: 0 on success, negative error code on failure.
 565 */
 566static int append_oa_status(struct i915_perf_stream *stream,
 567			    char __user *buf,
 568			    size_t count,
 569			    size_t *offset,
 570			    enum drm_i915_perf_record_type type)
 571{
 572	struct drm_i915_perf_record_header header = { type, 0, sizeof(header) };
 573
 574	if ((count - *offset) < header.size)
 575		return -ENOSPC;
 576
 577	if (copy_to_user(buf + *offset, &header, sizeof(header)))
 578		return -EFAULT;
 579
 580	(*offset) += header.size;
 581
 582	return 0;
 583}
 584
 585/**
 586 * append_oa_sample - Copies single OA report into userspace read() buffer.
 587 * @stream: An i915-perf stream opened for OA metrics
 588 * @buf: destination buffer given by userspace
 589 * @count: the number of bytes userspace wants to read
 590 * @offset: (inout): the current position for writing into @buf
 591 * @report: A single OA report to (optionally) include as part of the sample
 592 *
 593 * The contents of a sample are configured through `DRM_I915_PERF_PROP_SAMPLE_*`
 594 * properties when opening a stream, tracked as `stream->sample_flags`. This
 595 * function copies the requested components of a single sample to the given
 596 * read() @buf.
 597 *
 598 * The @buf @offset will only be updated on success.
 599 *
 600 * Returns: 0 on success, negative error code on failure.
 601 */
 602static int append_oa_sample(struct i915_perf_stream *stream,
 603			    char __user *buf,
 604			    size_t count,
 605			    size_t *offset,
 606			    const u8 *report)
 607{
 608	int report_size = stream->oa_buffer.format->size;
 609	struct drm_i915_perf_record_header header;
 610
 611	header.type = DRM_I915_PERF_RECORD_SAMPLE;
 612	header.pad = 0;
 613	header.size = stream->sample_size;
 614
 615	if ((count - *offset) < header.size)
 616		return -ENOSPC;
 617
 618	buf += *offset;
 619	if (copy_to_user(buf, &header, sizeof(header)))
 620		return -EFAULT;
 621	buf += sizeof(header);
 622
 623	if (copy_to_user(buf, report, report_size))
 624		return -EFAULT;
 625
 626	(*offset) += header.size;
 627
 628	return 0;
 629}
 630
 631/**
 632 * gen8_append_oa_reports - Copies all buffered OA reports into
 633 *			    userspace read() buffer.
 634 * @stream: An i915-perf stream opened for OA metrics
 635 * @buf: destination buffer given by userspace
 636 * @count: the number of bytes userspace wants to read
 637 * @offset: (inout): the current position for writing into @buf
 638 *
 639 * Notably any error condition resulting in a short read (-%ENOSPC or
 640 * -%EFAULT) will be returned even though one or more records may
 641 * have been successfully copied. In this case it's up to the caller
 642 * to decide if the error should be squashed before returning to
 643 * userspace.
 644 *
 645 * Note: reports are consumed from the head, and appended to the
 646 * tail, so the tail chases the head?... If you think that's mad
 647 * and back-to-front you're not alone, but this follows the
 648 * Gen PRM naming convention.
 649 *
 650 * Returns: 0 on success, negative error code on failure.
 651 */
 652static int gen8_append_oa_reports(struct i915_perf_stream *stream,
 653				  char __user *buf,
 654				  size_t count,
 655				  size_t *offset)
 656{
 657	struct intel_uncore *uncore = stream->uncore;
 658	int report_size = stream->oa_buffer.format->size;
 659	u8 *oa_buf_base = stream->oa_buffer.vaddr;
 660	u32 gtt_offset = i915_ggtt_offset(stream->oa_buffer.vma);
 661	u32 mask = (OA_BUFFER_SIZE - 1);
 662	size_t start_offset = *offset;
 663	unsigned long flags;
 664	u32 head, tail;
 665	int ret = 0;
 666
 667	if (drm_WARN_ON(&uncore->i915->drm, !stream->enabled))
 668		return -EIO;
 669
 670	spin_lock_irqsave(&stream->oa_buffer.ptr_lock, flags);
 671
 672	head = stream->oa_buffer.head;
 673	tail = stream->oa_buffer.tail;
 674
 675	spin_unlock_irqrestore(&stream->oa_buffer.ptr_lock, flags);
 676
 677	/*
 678	 * NB: oa_buffer.head/tail include the gtt_offset which we don't want
 679	 * while indexing relative to oa_buf_base.
 680	 */
 681	head -= gtt_offset;
 682	tail -= gtt_offset;
 683
 684	/*
 685	 * An out of bounds or misaligned head or tail pointer implies a driver
 686	 * bug since we validate + align the tail pointers we read from the
 687	 * hardware and we are in full control of the head pointer which should
 688	 * only be incremented by multiples of the report size (notably also
 689	 * all a power of two).
 690	 */
 691	if (drm_WARN_ONCE(&uncore->i915->drm,
 692			  head > OA_BUFFER_SIZE || head % report_size ||
 693			  tail > OA_BUFFER_SIZE || tail % report_size,
 694			  "Inconsistent OA buffer pointers: head = %u, tail = %u\n",
 695			  head, tail))
 696		return -EIO;
 697
 698
 699	for (/* none */;
 700	     OA_TAKEN(tail, head);
 701	     head = (head + report_size) & mask) {
 702		u8 *report = oa_buf_base + head;
 703		u32 *report32 = (void *)report;
 704		u32 ctx_id;
 705		u32 reason;
 706
 707		/*
 708		 * All the report sizes factor neatly into the buffer
 709		 * size so we never expect to see a report split
 710		 * between the beginning and end of the buffer.
 711		 *
 712		 * Given the initial alignment check a misalignment
 713		 * here would imply a driver bug that would result
 714		 * in an overrun.
 715		 */
 716		if (drm_WARN_ON(&uncore->i915->drm,
 717				(OA_BUFFER_SIZE - head) < report_size)) {
 718			drm_err(&uncore->i915->drm,
 719				"Spurious OA head ptr: non-integral report offset\n");
 720			break;
 721		}
 722
 723		/*
 724		 * The reason field includes flags identifying what
 725		 * triggered this specific report (mostly timer
 726		 * triggered or e.g. due to a context switch).
 727		 *
 728		 * This field is never expected to be zero so we can
 729		 * check that the report isn't invalid before copying
 730		 * it to userspace...
 731		 */
 732		reason = ((report32[0] >> OAREPORT_REASON_SHIFT) &
 733			  (GRAPHICS_VER(stream->perf->i915) == 12 ?
 734			   OAREPORT_REASON_MASK_EXTENDED :
 735			   OAREPORT_REASON_MASK));
 736
 737		ctx_id = report32[2] & stream->specific_ctx_id_mask;
 738
 739		/*
 740		 * Squash whatever is in the CTX_ID field if it's marked as
 741		 * invalid to be sure we avoid false-positive, single-context
 742		 * filtering below...
 743		 *
 744		 * Note: that we don't clear the valid_ctx_bit so userspace can
 745		 * understand that the ID has been squashed by the kernel.
 746		 */
 747		if (!(report32[0] & stream->perf->gen8_valid_ctx_bit) &&
 748		    GRAPHICS_VER(stream->perf->i915) <= 11)
 749			ctx_id = report32[2] = INVALID_CTX_ID;
 750
 751		/*
 752		 * NB: For Gen 8 the OA unit no longer supports clock gating
 753		 * off for a specific context and the kernel can't securely
 754		 * stop the counters from updating as system-wide / global
 755		 * values.
 756		 *
 757		 * Automatic reports now include a context ID so reports can be
 758		 * filtered on the cpu but it's not worth trying to
 759		 * automatically subtract/hide counter progress for other
 760		 * contexts while filtering since we can't stop userspace
 761		 * issuing MI_REPORT_PERF_COUNT commands which would still
 762		 * provide a side-band view of the real values.
 763		 *
 764		 * To allow userspace (such as Mesa/GL_INTEL_performance_query)
 765		 * to normalize counters for a single filtered context then it
 766		 * needs be forwarded bookend context-switch reports so that it
 767		 * can track switches in between MI_REPORT_PERF_COUNT commands
 768		 * and can itself subtract/ignore the progress of counters
 769		 * associated with other contexts. Note that the hardware
 770		 * automatically triggers reports when switching to a new
 771		 * context which are tagged with the ID of the newly active
 772		 * context. To avoid the complexity (and likely fragility) of
 773		 * reading ahead while parsing reports to try and minimize
 774		 * forwarding redundant context switch reports (i.e. between
 775		 * other, unrelated contexts) we simply elect to forward them
 776		 * all.
 777		 *
 778		 * We don't rely solely on the reason field to identify context
 779		 * switches since it's not-uncommon for periodic samples to
 780		 * identify a switch before any 'context switch' report.
 781		 */
 782		if (!stream->ctx ||
 783		    stream->specific_ctx_id == ctx_id ||
 784		    stream->oa_buffer.last_ctx_id == stream->specific_ctx_id ||
 785		    reason & OAREPORT_REASON_CTX_SWITCH) {
 786
 787			/*
 788			 * While filtering for a single context we avoid
 789			 * leaking the IDs of other contexts.
 790			 */
 791			if (stream->ctx &&
 792			    stream->specific_ctx_id != ctx_id) {
 793				report32[2] = INVALID_CTX_ID;
 794			}
 795
 796			ret = append_oa_sample(stream, buf, count, offset,
 797					       report);
 798			if (ret)
 799				break;
 800
 801			stream->oa_buffer.last_ctx_id = ctx_id;
 802		}
 803
 804		/*
 805		 * Clear out the first 2 dword as a mean to detect unlanded
 806		 * reports.
 807		 */
 808		report32[0] = 0;
 809		report32[1] = 0;
 810	}
 811
 812	if (start_offset != *offset) {
 813		i915_reg_t oaheadptr;
 814
 815		oaheadptr = GRAPHICS_VER(stream->perf->i915) == 12 ?
 816			    GEN12_OAG_OAHEADPTR : GEN8_OAHEADPTR;
 817
 818		spin_lock_irqsave(&stream->oa_buffer.ptr_lock, flags);
 819
 820		/*
 821		 * We removed the gtt_offset for the copy loop above, indexing
 822		 * relative to oa_buf_base so put back here...
 823		 */
 824		head += gtt_offset;
 825		intel_uncore_write(uncore, oaheadptr,
 826				   head & GEN12_OAG_OAHEADPTR_MASK);
 827		stream->oa_buffer.head = head;
 828
 829		spin_unlock_irqrestore(&stream->oa_buffer.ptr_lock, flags);
 830	}
 831
 832	return ret;
 833}
 834
 835/**
 836 * gen8_oa_read - copy status records then buffered OA reports
 837 * @stream: An i915-perf stream opened for OA metrics
 838 * @buf: destination buffer given by userspace
 839 * @count: the number of bytes userspace wants to read
 840 * @offset: (inout): the current position for writing into @buf
 841 *
 842 * Checks OA unit status registers and if necessary appends corresponding
 843 * status records for userspace (such as for a buffer full condition) and then
 844 * initiate appending any buffered OA reports.
 845 *
 846 * Updates @offset according to the number of bytes successfully copied into
 847 * the userspace buffer.
 848 *
 849 * NB: some data may be successfully copied to the userspace buffer
 850 * even if an error is returned, and this is reflected in the
 851 * updated @offset.
 852 *
 853 * Returns: zero on success or a negative error code
 854 */
 855static int gen8_oa_read(struct i915_perf_stream *stream,
 856			char __user *buf,
 857			size_t count,
 858			size_t *offset)
 859{
 860	struct intel_uncore *uncore = stream->uncore;
 861	u32 oastatus;
 862	i915_reg_t oastatus_reg;
 863	int ret;
 864
 865	if (drm_WARN_ON(&uncore->i915->drm, !stream->oa_buffer.vaddr))
 866		return -EIO;
 867
 868	oastatus_reg = GRAPHICS_VER(stream->perf->i915) == 12 ?
 869		       GEN12_OAG_OASTATUS : GEN8_OASTATUS;
 870
 871	oastatus = intel_uncore_read(uncore, oastatus_reg);
 872
 873	/*
 874	 * We treat OABUFFER_OVERFLOW as a significant error:
 875	 *
 876	 * Although theoretically we could handle this more gracefully
 877	 * sometimes, some Gens don't correctly suppress certain
 878	 * automatically triggered reports in this condition and so we
 879	 * have to assume that old reports are now being trampled
 880	 * over.
 881	 *
 882	 * Considering how we don't currently give userspace control
 883	 * over the OA buffer size and always configure a large 16MB
 884	 * buffer, then a buffer overflow does anyway likely indicate
 885	 * that something has gone quite badly wrong.
 886	 */
 887	if (oastatus & GEN8_OASTATUS_OABUFFER_OVERFLOW) {
 888		ret = append_oa_status(stream, buf, count, offset,
 889				       DRM_I915_PERF_RECORD_OA_BUFFER_LOST);
 890		if (ret)
 891			return ret;
 892
 893		drm_dbg(&stream->perf->i915->drm,
 894			"OA buffer overflow (exponent = %d): force restart\n",
 895			stream->period_exponent);
 896
 897		stream->perf->ops.oa_disable(stream);
 898		stream->perf->ops.oa_enable(stream);
 899
 900		/*
 901		 * Note: .oa_enable() is expected to re-init the oabuffer and
 902		 * reset GEN8_OASTATUS for us
 903		 */
 904		oastatus = intel_uncore_read(uncore, oastatus_reg);
 905	}
 906
 907	if (oastatus & GEN8_OASTATUS_REPORT_LOST) {
 908		ret = append_oa_status(stream, buf, count, offset,
 909				       DRM_I915_PERF_RECORD_OA_REPORT_LOST);
 910		if (ret)
 911			return ret;
 912
 913		intel_uncore_rmw(uncore, oastatus_reg,
 914				 GEN8_OASTATUS_COUNTER_OVERFLOW |
 915				 GEN8_OASTATUS_REPORT_LOST,
 916				 IS_GRAPHICS_VER(uncore->i915, 8, 11) ?
 917				 (GEN8_OASTATUS_HEAD_POINTER_WRAP |
 918				  GEN8_OASTATUS_TAIL_POINTER_WRAP) : 0);
 919	}
 920
 921	return gen8_append_oa_reports(stream, buf, count, offset);
 922}
 923
 924/**
 925 * gen7_append_oa_reports - Copies all buffered OA reports into
 926 *			    userspace read() buffer.
 927 * @stream: An i915-perf stream opened for OA metrics
 928 * @buf: destination buffer given by userspace
 929 * @count: the number of bytes userspace wants to read
 930 * @offset: (inout): the current position for writing into @buf
 931 *
 932 * Notably any error condition resulting in a short read (-%ENOSPC or
 933 * -%EFAULT) will be returned even though one or more records may
 934 * have been successfully copied. In this case it's up to the caller
 935 * to decide if the error should be squashed before returning to
 936 * userspace.
 937 *
 938 * Note: reports are consumed from the head, and appended to the
 939 * tail, so the tail chases the head?... If you think that's mad
 940 * and back-to-front you're not alone, but this follows the
 941 * Gen PRM naming convention.
 942 *
 943 * Returns: 0 on success, negative error code on failure.
 944 */
 945static int gen7_append_oa_reports(struct i915_perf_stream *stream,
 946				  char __user *buf,
 947				  size_t count,
 948				  size_t *offset)
 949{
 950	struct intel_uncore *uncore = stream->uncore;
 951	int report_size = stream->oa_buffer.format->size;
 952	u8 *oa_buf_base = stream->oa_buffer.vaddr;
 953	u32 gtt_offset = i915_ggtt_offset(stream->oa_buffer.vma);
 954	u32 mask = (OA_BUFFER_SIZE - 1);
 955	size_t start_offset = *offset;
 956	unsigned long flags;
 957	u32 head, tail;
 958	int ret = 0;
 959
 960	if (drm_WARN_ON(&uncore->i915->drm, !stream->enabled))
 961		return -EIO;
 962
 963	spin_lock_irqsave(&stream->oa_buffer.ptr_lock, flags);
 964
 965	head = stream->oa_buffer.head;
 966	tail = stream->oa_buffer.tail;
 967
 968	spin_unlock_irqrestore(&stream->oa_buffer.ptr_lock, flags);
 969
 970	/* NB: oa_buffer.head/tail include the gtt_offset which we don't want
 971	 * while indexing relative to oa_buf_base.
 972	 */
 973	head -= gtt_offset;
 974	tail -= gtt_offset;
 975
 976	/* An out of bounds or misaligned head or tail pointer implies a driver
 977	 * bug since we validate + align the tail pointers we read from the
 978	 * hardware and we are in full control of the head pointer which should
 979	 * only be incremented by multiples of the report size (notably also
 980	 * all a power of two).
 981	 */
 982	if (drm_WARN_ONCE(&uncore->i915->drm,
 983			  head > OA_BUFFER_SIZE || head % report_size ||
 984			  tail > OA_BUFFER_SIZE || tail % report_size,
 985			  "Inconsistent OA buffer pointers: head = %u, tail = %u\n",
 986			  head, tail))
 987		return -EIO;
 988
 989
 990	for (/* none */;
 991	     OA_TAKEN(tail, head);
 992	     head = (head + report_size) & mask) {
 993		u8 *report = oa_buf_base + head;
 994		u32 *report32 = (void *)report;
 995
 996		/* All the report sizes factor neatly into the buffer
 997		 * size so we never expect to see a report split
 998		 * between the beginning and end of the buffer.
 999		 *
1000		 * Given the initial alignment check a misalignment
1001		 * here would imply a driver bug that would result
1002		 * in an overrun.
1003		 */
1004		if (drm_WARN_ON(&uncore->i915->drm,
1005				(OA_BUFFER_SIZE - head) < report_size)) {
1006			drm_err(&uncore->i915->drm,
1007				"Spurious OA head ptr: non-integral report offset\n");
1008			break;
1009		}
1010
1011		/* The report-ID field for periodic samples includes
1012		 * some undocumented flags related to what triggered
1013		 * the report and is never expected to be zero so we
1014		 * can check that the report isn't invalid before
1015		 * copying it to userspace...
1016		 */
1017		if (report32[0] == 0) {
1018			if (__ratelimit(&stream->perf->spurious_report_rs))
1019				drm_notice(&uncore->i915->drm,
1020					   "Skipping spurious, invalid OA report\n");
1021			continue;
1022		}
1023
1024		ret = append_oa_sample(stream, buf, count, offset, report);
1025		if (ret)
1026			break;
1027
1028		/* Clear out the first 2 dwords as a mean to detect unlanded
1029		 * reports.
1030		 */
1031		report32[0] = 0;
1032		report32[1] = 0;
1033	}
1034
1035	if (start_offset != *offset) {
1036		spin_lock_irqsave(&stream->oa_buffer.ptr_lock, flags);
1037
1038		/* We removed the gtt_offset for the copy loop above, indexing
1039		 * relative to oa_buf_base so put back here...
1040		 */
1041		head += gtt_offset;
1042
1043		intel_uncore_write(uncore, GEN7_OASTATUS2,
1044				   (head & GEN7_OASTATUS2_HEAD_MASK) |
1045				   GEN7_OASTATUS2_MEM_SELECT_GGTT);
1046		stream->oa_buffer.head = head;
1047
1048		spin_unlock_irqrestore(&stream->oa_buffer.ptr_lock, flags);
1049	}
1050
1051	return ret;
1052}
1053
1054/**
1055 * gen7_oa_read - copy status records then buffered OA reports
1056 * @stream: An i915-perf stream opened for OA metrics
1057 * @buf: destination buffer given by userspace
1058 * @count: the number of bytes userspace wants to read
1059 * @offset: (inout): the current position for writing into @buf
1060 *
1061 * Checks Gen 7 specific OA unit status registers and if necessary appends
1062 * corresponding status records for userspace (such as for a buffer full
1063 * condition) and then initiate appending any buffered OA reports.
1064 *
1065 * Updates @offset according to the number of bytes successfully copied into
1066 * the userspace buffer.
1067 *
1068 * Returns: zero on success or a negative error code
1069 */
1070static int gen7_oa_read(struct i915_perf_stream *stream,
1071			char __user *buf,
1072			size_t count,
1073			size_t *offset)
1074{
1075	struct intel_uncore *uncore = stream->uncore;
1076	u32 oastatus1;
1077	int ret;
1078
1079	if (drm_WARN_ON(&uncore->i915->drm, !stream->oa_buffer.vaddr))
1080		return -EIO;
1081
1082	oastatus1 = intel_uncore_read(uncore, GEN7_OASTATUS1);
1083
1084	/* XXX: On Haswell we don't have a safe way to clear oastatus1
1085	 * bits while the OA unit is enabled (while the tail pointer
1086	 * may be updated asynchronously) so we ignore status bits
1087	 * that have already been reported to userspace.
1088	 */
1089	oastatus1 &= ~stream->perf->gen7_latched_oastatus1;
1090
1091	/* We treat OABUFFER_OVERFLOW as a significant error:
1092	 *
1093	 * - The status can be interpreted to mean that the buffer is
1094	 *   currently full (with a higher precedence than OA_TAKEN()
1095	 *   which will start to report a near-empty buffer after an
1096	 *   overflow) but it's awkward that we can't clear the status
1097	 *   on Haswell, so without a reset we won't be able to catch
1098	 *   the state again.
1099	 *
1100	 * - Since it also implies the HW has started overwriting old
1101	 *   reports it may also affect our sanity checks for invalid
1102	 *   reports when copying to userspace that assume new reports
1103	 *   are being written to cleared memory.
1104	 *
1105	 * - In the future we may want to introduce a flight recorder
1106	 *   mode where the driver will automatically maintain a safe
1107	 *   guard band between head/tail, avoiding this overflow
1108	 *   condition, but we avoid the added driver complexity for
1109	 *   now.
1110	 */
1111	if (unlikely(oastatus1 & GEN7_OASTATUS1_OABUFFER_OVERFLOW)) {
1112		ret = append_oa_status(stream, buf, count, offset,
1113				       DRM_I915_PERF_RECORD_OA_BUFFER_LOST);
1114		if (ret)
1115			return ret;
1116
1117		drm_dbg(&stream->perf->i915->drm,
1118			"OA buffer overflow (exponent = %d): force restart\n",
1119			stream->period_exponent);
1120
1121		stream->perf->ops.oa_disable(stream);
1122		stream->perf->ops.oa_enable(stream);
1123
1124		oastatus1 = intel_uncore_read(uncore, GEN7_OASTATUS1);
1125	}
1126
1127	if (unlikely(oastatus1 & GEN7_OASTATUS1_REPORT_LOST)) {
1128		ret = append_oa_status(stream, buf, count, offset,
1129				       DRM_I915_PERF_RECORD_OA_REPORT_LOST);
1130		if (ret)
1131			return ret;
1132		stream->perf->gen7_latched_oastatus1 |=
1133			GEN7_OASTATUS1_REPORT_LOST;
1134	}
1135
1136	return gen7_append_oa_reports(stream, buf, count, offset);
1137}
1138
1139/**
1140 * i915_oa_wait_unlocked - handles blocking IO until OA data available
1141 * @stream: An i915-perf stream opened for OA metrics
1142 *
1143 * Called when userspace tries to read() from a blocking stream FD opened
1144 * for OA metrics. It waits until the hrtimer callback finds a non-empty
1145 * OA buffer and wakes us.
1146 *
1147 * Note: it's acceptable to have this return with some false positives
1148 * since any subsequent read handling will return -EAGAIN if there isn't
1149 * really data ready for userspace yet.
1150 *
1151 * Returns: zero on success or a negative error code
1152 */
1153static int i915_oa_wait_unlocked(struct i915_perf_stream *stream)
1154{
1155	/* We would wait indefinitely if periodic sampling is not enabled */
1156	if (!stream->periodic)
1157		return -EIO;
1158
1159	return wait_event_interruptible(stream->poll_wq,
1160					oa_buffer_check_unlocked(stream));
1161}
1162
1163/**
1164 * i915_oa_poll_wait - call poll_wait() for an OA stream poll()
1165 * @stream: An i915-perf stream opened for OA metrics
1166 * @file: An i915 perf stream file
1167 * @wait: poll() state table
1168 *
1169 * For handling userspace polling on an i915 perf stream opened for OA metrics,
1170 * this starts a poll_wait with the wait queue that our hrtimer callback wakes
1171 * when it sees data ready to read in the circular OA buffer.
1172 */
1173static void i915_oa_poll_wait(struct i915_perf_stream *stream,
1174			      struct file *file,
1175			      poll_table *wait)
1176{
1177	poll_wait(file, &stream->poll_wq, wait);
1178}
1179
1180/**
1181 * i915_oa_read - just calls through to &i915_oa_ops->read
1182 * @stream: An i915-perf stream opened for OA metrics
1183 * @buf: destination buffer given by userspace
1184 * @count: the number of bytes userspace wants to read
1185 * @offset: (inout): the current position for writing into @buf
1186 *
1187 * Updates @offset according to the number of bytes successfully copied into
1188 * the userspace buffer.
1189 *
1190 * Returns: zero on success or a negative error code
1191 */
1192static int i915_oa_read(struct i915_perf_stream *stream,
1193			char __user *buf,
1194			size_t count,
1195			size_t *offset)
1196{
1197	return stream->perf->ops.read(stream, buf, count, offset);
1198}
1199
1200static struct intel_context *oa_pin_context(struct i915_perf_stream *stream)
1201{
1202	struct i915_gem_engines_iter it;
1203	struct i915_gem_context *ctx = stream->ctx;
1204	struct intel_context *ce;
1205	struct i915_gem_ww_ctx ww;
1206	int err = -ENODEV;
1207
1208	for_each_gem_engine(ce, i915_gem_context_lock_engines(ctx), it) {
1209		if (ce->engine != stream->engine) /* first match! */
1210			continue;
1211
1212		err = 0;
1213		break;
1214	}
1215	i915_gem_context_unlock_engines(ctx);
1216
1217	if (err)
1218		return ERR_PTR(err);
1219
1220	i915_gem_ww_ctx_init(&ww, true);
1221retry:
1222	/*
1223	 * As the ID is the gtt offset of the context's vma we
1224	 * pin the vma to ensure the ID remains fixed.
1225	 */
1226	err = intel_context_pin_ww(ce, &ww);
1227	if (err == -EDEADLK) {
1228		err = i915_gem_ww_ctx_backoff(&ww);
1229		if (!err)
1230			goto retry;
1231	}
1232	i915_gem_ww_ctx_fini(&ww);
1233
1234	if (err)
1235		return ERR_PTR(err);
1236
1237	stream->pinned_ctx = ce;
1238	return stream->pinned_ctx;
1239}
1240
1241static int
1242__store_reg_to_mem(struct i915_request *rq, i915_reg_t reg, u32 ggtt_offset)
1243{
1244	u32 *cs, cmd;
1245
1246	cmd = MI_STORE_REGISTER_MEM | MI_SRM_LRM_GLOBAL_GTT;
1247	if (GRAPHICS_VER(rq->engine->i915) >= 8)
1248		cmd++;
1249
1250	cs = intel_ring_begin(rq, 4);
1251	if (IS_ERR(cs))
1252		return PTR_ERR(cs);
1253
1254	*cs++ = cmd;
1255	*cs++ = i915_mmio_reg_offset(reg);
1256	*cs++ = ggtt_offset;
1257	*cs++ = 0;
1258
1259	intel_ring_advance(rq, cs);
1260
1261	return 0;
1262}
1263
1264static int
1265__read_reg(struct intel_context *ce, i915_reg_t reg, u32 ggtt_offset)
1266{
1267	struct i915_request *rq;
1268	int err;
1269
1270	rq = i915_request_create(ce);
1271	if (IS_ERR(rq))
1272		return PTR_ERR(rq);
1273
1274	i915_request_get(rq);
1275
1276	err = __store_reg_to_mem(rq, reg, ggtt_offset);
1277
1278	i915_request_add(rq);
1279	if (!err && i915_request_wait(rq, 0, HZ / 2) < 0)
1280		err = -ETIME;
1281
1282	i915_request_put(rq);
1283
1284	return err;
1285}
1286
1287static int
1288gen12_guc_sw_ctx_id(struct intel_context *ce, u32 *ctx_id)
1289{
1290	struct i915_vma *scratch;
1291	u32 *val;
1292	int err;
1293
1294	scratch = __vm_create_scratch_for_read_pinned(&ce->engine->gt->ggtt->vm, 4);
1295	if (IS_ERR(scratch))
1296		return PTR_ERR(scratch);
1297
1298	err = i915_vma_sync(scratch);
1299	if (err)
1300		goto err_scratch;
1301
1302	err = __read_reg(ce, RING_EXECLIST_STATUS_HI(ce->engine->mmio_base),
1303			 i915_ggtt_offset(scratch));
1304	if (err)
1305		goto err_scratch;
1306
1307	val = i915_gem_object_pin_map_unlocked(scratch->obj, I915_MAP_WB);
1308	if (IS_ERR(val)) {
1309		err = PTR_ERR(val);
1310		goto err_scratch;
1311	}
1312
1313	*ctx_id = *val;
1314	i915_gem_object_unpin_map(scratch->obj);
1315
1316err_scratch:
1317	i915_vma_unpin_and_release(&scratch, 0);
1318	return err;
1319}
1320
1321/*
1322 * For execlist mode of submission, pick an unused context id
1323 * 0 - (NUM_CONTEXT_TAG -1) are used by other contexts
1324 * XXX_MAX_CONTEXT_HW_ID is used by idle context
1325 *
1326 * For GuC mode of submission read context id from the upper dword of the
1327 * EXECLIST_STATUS register. Note that we read this value only once and expect
1328 * that the value stays fixed for the entire OA use case. There are cases where
1329 * GuC KMD implementation may deregister a context to reuse it's context id, but
1330 * we prevent that from happening to the OA context by pinning it.
1331 */
1332static int gen12_get_render_context_id(struct i915_perf_stream *stream)
1333{
1334	u32 ctx_id, mask;
1335	int ret;
1336
1337	if (intel_engine_uses_guc(stream->engine)) {
1338		ret = gen12_guc_sw_ctx_id(stream->pinned_ctx, &ctx_id);
1339		if (ret)
1340			return ret;
1341
1342		mask = ((1U << GEN12_GUC_SW_CTX_ID_WIDTH) - 1) <<
1343			(GEN12_GUC_SW_CTX_ID_SHIFT - 32);
1344	} else if (GRAPHICS_VER_FULL(stream->engine->i915) >= IP_VER(12, 50)) {
1345		ctx_id = (XEHP_MAX_CONTEXT_HW_ID - 1) <<
1346			(XEHP_SW_CTX_ID_SHIFT - 32);
1347
1348		mask = ((1U << XEHP_SW_CTX_ID_WIDTH) - 1) <<
1349			(XEHP_SW_CTX_ID_SHIFT - 32);
1350	} else {
1351		ctx_id = (GEN12_MAX_CONTEXT_HW_ID - 1) <<
1352			 (GEN11_SW_CTX_ID_SHIFT - 32);
1353
1354		mask = ((1U << GEN11_SW_CTX_ID_WIDTH) - 1) <<
1355			(GEN11_SW_CTX_ID_SHIFT - 32);
1356	}
1357	stream->specific_ctx_id = ctx_id & mask;
1358	stream->specific_ctx_id_mask = mask;
1359
1360	return 0;
1361}
1362
1363static bool oa_find_reg_in_lri(u32 *state, u32 reg, u32 *offset, u32 end)
1364{
1365	u32 idx = *offset;
1366	u32 len = min(MI_LRI_LEN(state[idx]) + idx, end);
1367	bool found = false;
1368
1369	idx++;
1370	for (; idx < len; idx += 2) {
1371		if (state[idx] == reg) {
1372			found = true;
1373			break;
1374		}
1375	}
1376
1377	*offset = idx;
1378	return found;
1379}
1380
1381static u32 oa_context_image_offset(struct intel_context *ce, u32 reg)
1382{
1383	u32 offset, len = (ce->engine->context_size - PAGE_SIZE) / 4;
1384	u32 *state = ce->lrc_reg_state;
1385
1386	if (drm_WARN_ON(&ce->engine->i915->drm, !state))
1387		return U32_MAX;
1388
1389	for (offset = 0; offset < len; ) {
1390		if (IS_MI_LRI_CMD(state[offset])) {
1391			/*
1392			 * We expect reg-value pairs in MI_LRI command, so
1393			 * MI_LRI_LEN() should be even, if not, issue a warning.
1394			 */
1395			drm_WARN_ON(&ce->engine->i915->drm,
1396				    MI_LRI_LEN(state[offset]) & 0x1);
1397
1398			if (oa_find_reg_in_lri(state, reg, &offset, len))
1399				break;
1400		} else {
1401			offset++;
1402		}
1403	}
1404
1405	return offset < len ? offset : U32_MAX;
1406}
1407
1408static int set_oa_ctx_ctrl_offset(struct intel_context *ce)
1409{
1410	i915_reg_t reg = GEN12_OACTXCONTROL(ce->engine->mmio_base);
1411	struct i915_perf *perf = &ce->engine->i915->perf;
1412	u32 offset = perf->ctx_oactxctrl_offset;
1413
1414	/* Do this only once. Failure is stored as offset of U32_MAX */
1415	if (offset)
1416		goto exit;
1417
1418	offset = oa_context_image_offset(ce, i915_mmio_reg_offset(reg));
1419	perf->ctx_oactxctrl_offset = offset;
1420
1421	drm_dbg(&ce->engine->i915->drm,
1422		"%s oa ctx control at 0x%08x dword offset\n",
1423		ce->engine->name, offset);
1424
1425exit:
1426	return offset && offset != U32_MAX ? 0 : -ENODEV;
1427}
1428
1429static bool engine_supports_mi_query(struct intel_engine_cs *engine)
1430{
1431	return engine->class == RENDER_CLASS;
1432}
1433
1434/**
1435 * oa_get_render_ctx_id - determine and hold ctx hw id
1436 * @stream: An i915-perf stream opened for OA metrics
1437 *
1438 * Determine the render context hw id, and ensure it remains fixed for the
1439 * lifetime of the stream. This ensures that we don't have to worry about
1440 * updating the context ID in OACONTROL on the fly.
1441 *
1442 * Returns: zero on success or a negative error code
1443 */
1444static int oa_get_render_ctx_id(struct i915_perf_stream *stream)
1445{
1446	struct intel_context *ce;
1447	int ret = 0;
1448
1449	ce = oa_pin_context(stream);
1450	if (IS_ERR(ce))
1451		return PTR_ERR(ce);
1452
1453	if (engine_supports_mi_query(stream->engine) &&
1454	    HAS_LOGICAL_RING_CONTEXTS(stream->perf->i915)) {
1455		/*
1456		 * We are enabling perf query here. If we don't find the context
1457		 * offset here, just return an error.
1458		 */
1459		ret = set_oa_ctx_ctrl_offset(ce);
1460		if (ret) {
1461			intel_context_unpin(ce);
1462			drm_err(&stream->perf->i915->drm,
1463				"Enabling perf query failed for %s\n",
1464				stream->engine->name);
1465			return ret;
1466		}
1467	}
1468
1469	switch (GRAPHICS_VER(ce->engine->i915)) {
1470	case 7: {
1471		/*
1472		 * On Haswell we don't do any post processing of the reports
1473		 * and don't need to use the mask.
1474		 */
1475		stream->specific_ctx_id = i915_ggtt_offset(ce->state);
1476		stream->specific_ctx_id_mask = 0;
1477		break;
1478	}
1479
1480	case 8:
1481	case 9:
1482		if (intel_engine_uses_guc(ce->engine)) {
1483			/*
1484			 * When using GuC, the context descriptor we write in
1485			 * i915 is read by GuC and rewritten before it's
1486			 * actually written into the hardware. The LRCA is
1487			 * what is put into the context id field of the
1488			 * context descriptor by GuC. Because it's aligned to
1489			 * a page, the lower 12bits are always at 0 and
1490			 * dropped by GuC. They won't be part of the context
1491			 * ID in the OA reports, so squash those lower bits.
1492			 */
1493			stream->specific_ctx_id = ce->lrc.lrca >> 12;
1494
1495			/*
1496			 * GuC uses the top bit to signal proxy submission, so
1497			 * ignore that bit.
1498			 */
1499			stream->specific_ctx_id_mask =
1500				(1U << (GEN8_CTX_ID_WIDTH - 1)) - 1;
1501		} else {
1502			stream->specific_ctx_id_mask =
1503				(1U << GEN8_CTX_ID_WIDTH) - 1;
1504			stream->specific_ctx_id = stream->specific_ctx_id_mask;
1505		}
1506		break;
1507
1508	case 11:
1509	case 12:
1510		ret = gen12_get_render_context_id(stream);
1511		break;
1512
1513	default:
1514		MISSING_CASE(GRAPHICS_VER(ce->engine->i915));
1515	}
1516
1517	ce->tag = stream->specific_ctx_id;
1518
1519	drm_dbg(&stream->perf->i915->drm,
1520		"filtering on ctx_id=0x%x ctx_id_mask=0x%x\n",
1521		stream->specific_ctx_id,
1522		stream->specific_ctx_id_mask);
1523
1524	return ret;
1525}
1526
1527/**
1528 * oa_put_render_ctx_id - counterpart to oa_get_render_ctx_id releases hold
1529 * @stream: An i915-perf stream opened for OA metrics
1530 *
1531 * In case anything needed doing to ensure the context HW ID would remain valid
1532 * for the lifetime of the stream, then that can be undone here.
1533 */
1534static void oa_put_render_ctx_id(struct i915_perf_stream *stream)
1535{
1536	struct intel_context *ce;
1537
1538	ce = fetch_and_zero(&stream->pinned_ctx);
1539	if (ce) {
1540		ce->tag = 0; /* recomputed on next submission after parking */
1541		intel_context_unpin(ce);
1542	}
1543
1544	stream->specific_ctx_id = INVALID_CTX_ID;
1545	stream->specific_ctx_id_mask = 0;
1546}
1547
1548static void
1549free_oa_buffer(struct i915_perf_stream *stream)
1550{
1551	i915_vma_unpin_and_release(&stream->oa_buffer.vma,
1552				   I915_VMA_RELEASE_MAP);
1553
1554	stream->oa_buffer.vaddr = NULL;
1555}
1556
1557static void
1558free_oa_configs(struct i915_perf_stream *stream)
1559{
1560	struct i915_oa_config_bo *oa_bo, *tmp;
1561
1562	i915_oa_config_put(stream->oa_config);
1563	llist_for_each_entry_safe(oa_bo, tmp, stream->oa_config_bos.first, node)
1564		free_oa_config_bo(oa_bo);
1565}
1566
1567static void
1568free_noa_wait(struct i915_perf_stream *stream)
1569{
1570	i915_vma_unpin_and_release(&stream->noa_wait, 0);
1571}
1572
1573static void i915_oa_stream_destroy(struct i915_perf_stream *stream)
1574{
1575	struct i915_perf *perf = stream->perf;
1576	struct intel_gt *gt = stream->engine->gt;
1577
1578	if (WARN_ON(stream != gt->perf.exclusive_stream))
1579		return;
1580
1581	/*
1582	 * Unset exclusive_stream first, it will be checked while disabling
1583	 * the metric set on gen8+.
1584	 *
1585	 * See i915_oa_init_reg_state() and lrc_configure_all_contexts()
1586	 */
1587	WRITE_ONCE(gt->perf.exclusive_stream, NULL);
1588	perf->ops.disable_metric_set(stream);
1589
1590	free_oa_buffer(stream);
1591
1592	/*
1593	 * Wa_16011777198:dg2: Unset the override of GUCRC mode to enable rc6.
1594	 */
1595	if (intel_uc_uses_guc_rc(&gt->uc) &&
1596	    (IS_DG2_GRAPHICS_STEP(gt->i915, G10, STEP_A0, STEP_C0) ||
1597	     IS_DG2_GRAPHICS_STEP(gt->i915, G11, STEP_A0, STEP_B0)))
1598		drm_WARN_ON(&gt->i915->drm,
1599			    intel_guc_slpc_unset_gucrc_mode(&gt->uc.guc.slpc));
1600
1601	intel_uncore_forcewake_put(stream->uncore, FORCEWAKE_ALL);
1602	intel_engine_pm_put(stream->engine);
1603
1604	if (stream->ctx)
1605		oa_put_render_ctx_id(stream);
1606
1607	free_oa_configs(stream);
1608	free_noa_wait(stream);
1609
1610	if (perf->spurious_report_rs.missed) {
1611		drm_notice(&gt->i915->drm,
1612			   "%d spurious OA report notices suppressed due to ratelimiting\n",
1613			   perf->spurious_report_rs.missed);
1614	}
1615}
1616
1617static void gen7_init_oa_buffer(struct i915_perf_stream *stream)
1618{
1619	struct intel_uncore *uncore = stream->uncore;
1620	u32 gtt_offset = i915_ggtt_offset(stream->oa_buffer.vma);
1621	unsigned long flags;
1622
1623	spin_lock_irqsave(&stream->oa_buffer.ptr_lock, flags);
1624
1625	/* Pre-DevBDW: OABUFFER must be set with counters off,
1626	 * before OASTATUS1, but after OASTATUS2
1627	 */
1628	intel_uncore_write(uncore, GEN7_OASTATUS2, /* head */
1629			   gtt_offset | GEN7_OASTATUS2_MEM_SELECT_GGTT);
1630	stream->oa_buffer.head = gtt_offset;
1631
1632	intel_uncore_write(uncore, GEN7_OABUFFER, gtt_offset);
1633
1634	intel_uncore_write(uncore, GEN7_OASTATUS1, /* tail */
1635			   gtt_offset | OABUFFER_SIZE_16M);
1636
1637	/* Mark that we need updated tail pointers to read from... */
1638	stream->oa_buffer.aging_tail = INVALID_TAIL_PTR;
1639	stream->oa_buffer.tail = gtt_offset;
1640
1641	spin_unlock_irqrestore(&stream->oa_buffer.ptr_lock, flags);
1642
1643	/* On Haswell we have to track which OASTATUS1 flags we've
1644	 * already seen since they can't be cleared while periodic
1645	 * sampling is enabled.
1646	 */
1647	stream->perf->gen7_latched_oastatus1 = 0;
1648
1649	/* NB: although the OA buffer will initially be allocated
1650	 * zeroed via shmfs (and so this memset is redundant when
1651	 * first allocating), we may re-init the OA buffer, either
1652	 * when re-enabling a stream or in error/reset paths.
1653	 *
1654	 * The reason we clear the buffer for each re-init is for the
1655	 * sanity check in gen7_append_oa_reports() that looks at the
1656	 * report-id field to make sure it's non-zero which relies on
1657	 * the assumption that new reports are being written to zeroed
1658	 * memory...
1659	 */
1660	memset(stream->oa_buffer.vaddr, 0, OA_BUFFER_SIZE);
1661}
1662
1663static void gen8_init_oa_buffer(struct i915_perf_stream *stream)
1664{
1665	struct intel_uncore *uncore = stream->uncore;
1666	u32 gtt_offset = i915_ggtt_offset(stream->oa_buffer.vma);
1667	unsigned long flags;
1668
1669	spin_lock_irqsave(&stream->oa_buffer.ptr_lock, flags);
1670
1671	intel_uncore_write(uncore, GEN8_OASTATUS, 0);
1672	intel_uncore_write(uncore, GEN8_OAHEADPTR, gtt_offset);
1673	stream->oa_buffer.head = gtt_offset;
1674
1675	intel_uncore_write(uncore, GEN8_OABUFFER_UDW, 0);
1676
1677	/*
1678	 * PRM says:
1679	 *
1680	 *  "This MMIO must be set before the OATAILPTR
1681	 *  register and after the OAHEADPTR register. This is
1682	 *  to enable proper functionality of the overflow
1683	 *  bit."
1684	 */
1685	intel_uncore_write(uncore, GEN8_OABUFFER, gtt_offset |
1686		   OABUFFER_SIZE_16M | GEN8_OABUFFER_MEM_SELECT_GGTT);
1687	intel_uncore_write(uncore, GEN8_OATAILPTR, gtt_offset & GEN8_OATAILPTR_MASK);
1688
1689	/* Mark that we need updated tail pointers to read from... */
1690	stream->oa_buffer.aging_tail = INVALID_TAIL_PTR;
1691	stream->oa_buffer.tail = gtt_offset;
1692
1693	/*
1694	 * Reset state used to recognise context switches, affecting which
1695	 * reports we will forward to userspace while filtering for a single
1696	 * context.
1697	 */
1698	stream->oa_buffer.last_ctx_id = INVALID_CTX_ID;
1699
1700	spin_unlock_irqrestore(&stream->oa_buffer.ptr_lock, flags);
1701
1702	/*
1703	 * NB: although the OA buffer will initially be allocated
1704	 * zeroed via shmfs (and so this memset is redundant when
1705	 * first allocating), we may re-init the OA buffer, either
1706	 * when re-enabling a stream or in error/reset paths.
1707	 *
1708	 * The reason we clear the buffer for each re-init is for the
1709	 * sanity check in gen8_append_oa_reports() that looks at the
1710	 * reason field to make sure it's non-zero which relies on
1711	 * the assumption that new reports are being written to zeroed
1712	 * memory...
1713	 */
1714	memset(stream->oa_buffer.vaddr, 0, OA_BUFFER_SIZE);
1715}
1716
1717static void gen12_init_oa_buffer(struct i915_perf_stream *stream)
1718{
1719	struct intel_uncore *uncore = stream->uncore;
1720	u32 gtt_offset = i915_ggtt_offset(stream->oa_buffer.vma);
1721	unsigned long flags;
1722
1723	spin_lock_irqsave(&stream->oa_buffer.ptr_lock, flags);
1724
1725	intel_uncore_write(uncore, GEN12_OAG_OASTATUS, 0);
1726	intel_uncore_write(uncore, GEN12_OAG_OAHEADPTR,
1727			   gtt_offset & GEN12_OAG_OAHEADPTR_MASK);
1728	stream->oa_buffer.head = gtt_offset;
1729
1730	/*
1731	 * PRM says:
1732	 *
1733	 *  "This MMIO must be set before the OATAILPTR
1734	 *  register and after the OAHEADPTR register. This is
1735	 *  to enable proper functionality of the overflow
1736	 *  bit."
1737	 */
1738	intel_uncore_write(uncore, GEN12_OAG_OABUFFER, gtt_offset |
1739			   OABUFFER_SIZE_16M | GEN8_OABUFFER_MEM_SELECT_GGTT);
1740	intel_uncore_write(uncore, GEN12_OAG_OATAILPTR,
1741			   gtt_offset & GEN12_OAG_OATAILPTR_MASK);
1742
1743	/* Mark that we need updated tail pointers to read from... */
1744	stream->oa_buffer.aging_tail = INVALID_TAIL_PTR;
1745	stream->oa_buffer.tail = gtt_offset;
1746
1747	/*
1748	 * Reset state used to recognise context switches, affecting which
1749	 * reports we will forward to userspace while filtering for a single
1750	 * context.
1751	 */
1752	stream->oa_buffer.last_ctx_id = INVALID_CTX_ID;
1753
1754	spin_unlock_irqrestore(&stream->oa_buffer.ptr_lock, flags);
1755
1756	/*
1757	 * NB: although the OA buffer will initially be allocated
1758	 * zeroed via shmfs (and so this memset is redundant when
1759	 * first allocating), we may re-init the OA buffer, either
1760	 * when re-enabling a stream or in error/reset paths.
1761	 *
1762	 * The reason we clear the buffer for each re-init is for the
1763	 * sanity check in gen8_append_oa_reports() that looks at the
1764	 * reason field to make sure it's non-zero which relies on
1765	 * the assumption that new reports are being written to zeroed
1766	 * memory...
1767	 */
1768	memset(stream->oa_buffer.vaddr, 0,
1769	       stream->oa_buffer.vma->size);
1770}
1771
1772static int alloc_oa_buffer(struct i915_perf_stream *stream)
1773{
1774	struct drm_i915_private *i915 = stream->perf->i915;
1775	struct intel_gt *gt = stream->engine->gt;
1776	struct drm_i915_gem_object *bo;
1777	struct i915_vma *vma;
1778	int ret;
1779
1780	if (drm_WARN_ON(&i915->drm, stream->oa_buffer.vma))
1781		return -ENODEV;
1782
1783	BUILD_BUG_ON_NOT_POWER_OF_2(OA_BUFFER_SIZE);
1784	BUILD_BUG_ON(OA_BUFFER_SIZE < SZ_128K || OA_BUFFER_SIZE > SZ_16M);
1785
1786	bo = i915_gem_object_create_shmem(stream->perf->i915, OA_BUFFER_SIZE);
1787	if (IS_ERR(bo)) {
1788		drm_err(&i915->drm, "Failed to allocate OA buffer\n");
1789		return PTR_ERR(bo);
1790	}
1791
1792	i915_gem_object_set_cache_coherency(bo, I915_CACHE_LLC);
1793
1794	/* PreHSW required 512K alignment, HSW requires 16M */
1795	vma = i915_vma_instance(bo, &gt->ggtt->vm, NULL);
1796	if (IS_ERR(vma)) {
1797		ret = PTR_ERR(vma);
1798		goto err_unref;
1799	}
1800
1801	/*
1802	 * PreHSW required 512K alignment.
1803	 * HSW and onwards, align to requested size of OA buffer.
1804	 */
1805	ret = i915_vma_pin(vma, 0, SZ_16M, PIN_GLOBAL | PIN_HIGH);
1806	if (ret) {
1807		drm_err(&gt->i915->drm, "Failed to pin OA buffer %d\n", ret);
1808		goto err_unref;
1809	}
1810
1811	stream->oa_buffer.vma = vma;
1812
1813	stream->oa_buffer.vaddr =
1814		i915_gem_object_pin_map_unlocked(bo, I915_MAP_WB);
1815	if (IS_ERR(stream->oa_buffer.vaddr)) {
1816		ret = PTR_ERR(stream->oa_buffer.vaddr);
1817		goto err_unpin;
1818	}
1819
1820	return 0;
1821
1822err_unpin:
1823	__i915_vma_unpin(vma);
1824
1825err_unref:
1826	i915_gem_object_put(bo);
1827
1828	stream->oa_buffer.vaddr = NULL;
1829	stream->oa_buffer.vma = NULL;
1830
1831	return ret;
1832}
1833
1834static u32 *save_restore_register(struct i915_perf_stream *stream, u32 *cs,
1835				  bool save, i915_reg_t reg, u32 offset,
1836				  u32 dword_count)
1837{
1838	u32 cmd;
1839	u32 d;
1840
1841	cmd = save ? MI_STORE_REGISTER_MEM : MI_LOAD_REGISTER_MEM;
1842	cmd |= MI_SRM_LRM_GLOBAL_GTT;
1843	if (GRAPHICS_VER(stream->perf->i915) >= 8)
1844		cmd++;
1845
1846	for (d = 0; d < dword_count; d++) {
1847		*cs++ = cmd;
1848		*cs++ = i915_mmio_reg_offset(reg) + 4 * d;
1849		*cs++ = intel_gt_scratch_offset(stream->engine->gt,
1850						offset) + 4 * d;
1851		*cs++ = 0;
1852	}
1853
1854	return cs;
1855}
1856
1857static int alloc_noa_wait(struct i915_perf_stream *stream)
1858{
1859	struct drm_i915_private *i915 = stream->perf->i915;
1860	struct intel_gt *gt = stream->engine->gt;
1861	struct drm_i915_gem_object *bo;
1862	struct i915_vma *vma;
1863	const u64 delay_ticks = 0xffffffffffffffff -
1864		intel_gt_ns_to_clock_interval(to_gt(stream->perf->i915),
1865		atomic64_read(&stream->perf->noa_programming_delay));
1866	const u32 base = stream->engine->mmio_base;
1867#define CS_GPR(x) GEN8_RING_CS_GPR(base, x)
1868	u32 *batch, *ts0, *cs, *jump;
1869	struct i915_gem_ww_ctx ww;
1870	int ret, i;
1871	enum {
1872		START_TS,
1873		NOW_TS,
1874		DELTA_TS,
1875		JUMP_PREDICATE,
1876		DELTA_TARGET,
1877		N_CS_GPR
1878	};
1879	i915_reg_t mi_predicate_result = HAS_MI_SET_PREDICATE(i915) ?
1880					  MI_PREDICATE_RESULT_2_ENGINE(base) :
1881					  MI_PREDICATE_RESULT_1(RENDER_RING_BASE);
1882
1883	bo = i915_gem_object_create_internal(i915, 4096);
1884	if (IS_ERR(bo)) {
1885		drm_err(&i915->drm,
1886			"Failed to allocate NOA wait batchbuffer\n");
1887		return PTR_ERR(bo);
1888	}
1889
1890	i915_gem_ww_ctx_init(&ww, true);
1891retry:
1892	ret = i915_gem_object_lock(bo, &ww);
1893	if (ret)
1894		goto out_ww;
1895
1896	/*
1897	 * We pin in GGTT because we jump into this buffer now because
1898	 * multiple OA config BOs will have a jump to this address and it
1899	 * needs to be fixed during the lifetime of the i915/perf stream.
1900	 */
1901	vma = i915_vma_instance(bo, &gt->ggtt->vm, NULL);
1902	if (IS_ERR(vma)) {
1903		ret = PTR_ERR(vma);
1904		goto out_ww;
1905	}
1906
1907	ret = i915_vma_pin_ww(vma, &ww, 0, 0, PIN_GLOBAL | PIN_HIGH);
1908	if (ret)
1909		goto out_ww;
1910
1911	batch = cs = i915_gem_object_pin_map(bo, I915_MAP_WB);
1912	if (IS_ERR(batch)) {
1913		ret = PTR_ERR(batch);
1914		goto err_unpin;
1915	}
1916
1917	/* Save registers. */
1918	for (i = 0; i < N_CS_GPR; i++)
1919		cs = save_restore_register(
1920			stream, cs, true /* save */, CS_GPR(i),
1921			INTEL_GT_SCRATCH_FIELD_PERF_CS_GPR + 8 * i, 2);
1922	cs = save_restore_register(
1923		stream, cs, true /* save */, mi_predicate_result,
1924		INTEL_GT_SCRATCH_FIELD_PERF_PREDICATE_RESULT_1, 1);
1925
1926	/* First timestamp snapshot location. */
1927	ts0 = cs;
1928
1929	/*
1930	 * Initial snapshot of the timestamp register to implement the wait.
1931	 * We work with 32b values, so clear out the top 32b bits of the
1932	 * register because the ALU works 64bits.
1933	 */
1934	*cs++ = MI_LOAD_REGISTER_IMM(1);
1935	*cs++ = i915_mmio_reg_offset(CS_GPR(START_TS)) + 4;
1936	*cs++ = 0;
1937	*cs++ = MI_LOAD_REGISTER_REG | (3 - 2);
1938	*cs++ = i915_mmio_reg_offset(RING_TIMESTAMP(base));
1939	*cs++ = i915_mmio_reg_offset(CS_GPR(START_TS));
1940
1941	/*
1942	 * This is the location we're going to jump back into until the
1943	 * required amount of time has passed.
1944	 */
1945	jump = cs;
1946
1947	/*
1948	 * Take another snapshot of the timestamp register. Take care to clear
1949	 * up the top 32bits of CS_GPR(1) as we're using it for other
1950	 * operations below.
1951	 */
1952	*cs++ = MI_LOAD_REGISTER_IMM(1);
1953	*cs++ = i915_mmio_reg_offset(CS_GPR(NOW_TS)) + 4;
1954	*cs++ = 0;
1955	*cs++ = MI_LOAD_REGISTER_REG | (3 - 2);
1956	*cs++ = i915_mmio_reg_offset(RING_TIMESTAMP(base));
1957	*cs++ = i915_mmio_reg_offset(CS_GPR(NOW_TS));
1958
1959	/*
1960	 * Do a diff between the 2 timestamps and store the result back into
1961	 * CS_GPR(1).
1962	 */
1963	*cs++ = MI_MATH(5);
1964	*cs++ = MI_MATH_LOAD(MI_MATH_REG_SRCA, MI_MATH_REG(NOW_TS));
1965	*cs++ = MI_MATH_LOAD(MI_MATH_REG_SRCB, MI_MATH_REG(START_TS));
1966	*cs++ = MI_MATH_SUB;
1967	*cs++ = MI_MATH_STORE(MI_MATH_REG(DELTA_TS), MI_MATH_REG_ACCU);
1968	*cs++ = MI_MATH_STORE(MI_MATH_REG(JUMP_PREDICATE), MI_MATH_REG_CF);
1969
1970	/*
1971	 * Transfer the carry flag (set to 1 if ts1 < ts0, meaning the
1972	 * timestamp have rolled over the 32bits) into the predicate register
1973	 * to be used for the predicated jump.
1974	 */
1975	*cs++ = MI_LOAD_REGISTER_REG | (3 - 2);
1976	*cs++ = i915_mmio_reg_offset(CS_GPR(JUMP_PREDICATE));
1977	*cs++ = i915_mmio_reg_offset(mi_predicate_result);
1978
1979	if (HAS_MI_SET_PREDICATE(i915))
1980		*cs++ = MI_SET_PREDICATE | 1;
1981
1982	/* Restart from the beginning if we had timestamps roll over. */
1983	*cs++ = (GRAPHICS_VER(i915) < 8 ?
1984		 MI_BATCH_BUFFER_START :
1985		 MI_BATCH_BUFFER_START_GEN8) |
1986		MI_BATCH_PREDICATE;
1987	*cs++ = i915_ggtt_offset(vma) + (ts0 - batch) * 4;
1988	*cs++ = 0;
1989
1990	if (HAS_MI_SET_PREDICATE(i915))
1991		*cs++ = MI_SET_PREDICATE;
1992
1993	/*
1994	 * Now add the diff between to previous timestamps and add it to :
1995	 *      (((1 * << 64) - 1) - delay_ns)
1996	 *
1997	 * When the Carry Flag contains 1 this means the elapsed time is
1998	 * longer than the expected delay, and we can exit the wait loop.
1999	 */
2000	*cs++ = MI_LOAD_REGISTER_IMM(2);
2001	*cs++ = i915_mmio_reg_offset(CS_GPR(DELTA_TARGET));
2002	*cs++ = lower_32_bits(delay_ticks);
2003	*cs++ = i915_mmio_reg_offset(CS_GPR(DELTA_TARGET)) + 4;
2004	*cs++ = upper_32_bits(delay_ticks);
2005
2006	*cs++ = MI_MATH(4);
2007	*cs++ = MI_MATH_LOAD(MI_MATH_REG_SRCA, MI_MATH_REG(DELTA_TS));
2008	*cs++ = MI_MATH_LOAD(MI_MATH_REG_SRCB, MI_MATH_REG(DELTA_TARGET));
2009	*cs++ = MI_MATH_ADD;
2010	*cs++ = MI_MATH_STOREINV(MI_MATH_REG(JUMP_PREDICATE), MI_MATH_REG_CF);
2011
2012	*cs++ = MI_ARB_CHECK;
2013
2014	/*
2015	 * Transfer the result into the predicate register to be used for the
2016	 * predicated jump.
2017	 */
2018	*cs++ = MI_LOAD_REGISTER_REG | (3 - 2);
2019	*cs++ = i915_mmio_reg_offset(CS_GPR(JUMP_PREDICATE));
2020	*cs++ = i915_mmio_reg_offset(mi_predicate_result);
2021
2022	if (HAS_MI_SET_PREDICATE(i915))
2023		*cs++ = MI_SET_PREDICATE | 1;
2024
2025	/* Predicate the jump.  */
2026	*cs++ = (GRAPHICS_VER(i915) < 8 ?
2027		 MI_BATCH_BUFFER_START :
2028		 MI_BATCH_BUFFER_START_GEN8) |
2029		MI_BATCH_PREDICATE;
2030	*cs++ = i915_ggtt_offset(vma) + (jump - batch) * 4;
2031	*cs++ = 0;
2032
2033	if (HAS_MI_SET_PREDICATE(i915))
2034		*cs++ = MI_SET_PREDICATE;
2035
2036	/* Restore registers. */
2037	for (i = 0; i < N_CS_GPR; i++)
2038		cs = save_restore_register(
2039			stream, cs, false /* restore */, CS_GPR(i),
2040			INTEL_GT_SCRATCH_FIELD_PERF_CS_GPR + 8 * i, 2);
2041	cs = save_restore_register(
2042		stream, cs, false /* restore */, mi_predicate_result,
2043		INTEL_GT_SCRATCH_FIELD_PERF_PREDICATE_RESULT_1, 1);
2044
2045	/* And return to the ring. */
2046	*cs++ = MI_BATCH_BUFFER_END;
2047
2048	GEM_BUG_ON(cs - batch > PAGE_SIZE / sizeof(*batch));
2049
2050	i915_gem_object_flush_map(bo);
2051	__i915_gem_object_release_map(bo);
2052
2053	stream->noa_wait = vma;
2054	goto out_ww;
2055
2056err_unpin:
2057	i915_vma_unpin_and_release(&vma, 0);
2058out_ww:
2059	if (ret == -EDEADLK) {
2060		ret = i915_gem_ww_ctx_backoff(&ww);
2061		if (!ret)
2062			goto retry;
2063	}
2064	i915_gem_ww_ctx_fini(&ww);
2065	if (ret)
2066		i915_gem_object_put(bo);
2067	return ret;
2068}
2069
2070static u32 *write_cs_mi_lri(u32 *cs,
2071			    const struct i915_oa_reg *reg_data,
2072			    u32 n_regs)
2073{
2074	u32 i;
2075
2076	for (i = 0; i < n_regs; i++) {
2077		if ((i % MI_LOAD_REGISTER_IMM_MAX_REGS) == 0) {
2078			u32 n_lri = min_t(u32,
2079					  n_regs - i,
2080					  MI_LOAD_REGISTER_IMM_MAX_REGS);
2081
2082			*cs++ = MI_LOAD_REGISTER_IMM(n_lri);
2083		}
2084		*cs++ = i915_mmio_reg_offset(reg_data[i].addr);
2085		*cs++ = reg_data[i].value;
2086	}
2087
2088	return cs;
2089}
2090
2091static int num_lri_dwords(int num_regs)
2092{
2093	int count = 0;
2094
2095	if (num_regs > 0) {
2096		count += DIV_ROUND_UP(num_regs, MI_LOAD_REGISTER_IMM_MAX_REGS);
2097		count += num_regs * 2;
2098	}
2099
2100	return count;
2101}
2102
2103static struct i915_oa_config_bo *
2104alloc_oa_config_buffer(struct i915_perf_stream *stream,
2105		       struct i915_oa_config *oa_config)
2106{
2107	struct drm_i915_gem_object *obj;
2108	struct i915_oa_config_bo *oa_bo;
2109	struct i915_gem_ww_ctx ww;
2110	size_t config_length = 0;
2111	u32 *cs;
2112	int err;
2113
2114	oa_bo = kzalloc(sizeof(*oa_bo), GFP_KERNEL);
2115	if (!oa_bo)
2116		return ERR_PTR(-ENOMEM);
2117
2118	config_length += num_lri_dwords(oa_config->mux_regs_len);
2119	config_length += num_lri_dwords(oa_config->b_counter_regs_len);
2120	config_length += num_lri_dwords(oa_config->flex_regs_len);
2121	config_length += 3; /* MI_BATCH_BUFFER_START */
2122	config_length = ALIGN(sizeof(u32) * config_length, I915_GTT_PAGE_SIZE);
2123
2124	obj = i915_gem_object_create_shmem(stream->perf->i915, config_length);
2125	if (IS_ERR(obj)) {
2126		err = PTR_ERR(obj);
2127		goto err_free;
2128	}
2129
2130	i915_gem_ww_ctx_init(&ww, true);
2131retry:
2132	err = i915_gem_object_lock(obj, &ww);
2133	if (err)
2134		goto out_ww;
2135
2136	cs = i915_gem_object_pin_map(obj, I915_MAP_WB);
2137	if (IS_ERR(cs)) {
2138		err = PTR_ERR(cs);
2139		goto out_ww;
2140	}
2141
2142	cs = write_cs_mi_lri(cs,
2143			     oa_config->mux_regs,
2144			     oa_config->mux_regs_len);
2145	cs = write_cs_mi_lri(cs,
2146			     oa_config->b_counter_regs,
2147			     oa_config->b_counter_regs_len);
2148	cs = write_cs_mi_lri(cs,
2149			     oa_config->flex_regs,
2150			     oa_config->flex_regs_len);
2151
2152	/* Jump into the active wait. */
2153	*cs++ = (GRAPHICS_VER(stream->perf->i915) < 8 ?
2154		 MI_BATCH_BUFFER_START :
2155		 MI_BATCH_BUFFER_START_GEN8);
2156	*cs++ = i915_ggtt_offset(stream->noa_wait);
2157	*cs++ = 0;
2158
2159	i915_gem_object_flush_map(obj);
2160	__i915_gem_object_release_map(obj);
2161
2162	oa_bo->vma = i915_vma_instance(obj,
2163				       &stream->engine->gt->ggtt->vm,
2164				       NULL);
2165	if (IS_ERR(oa_bo->vma)) {
2166		err = PTR_ERR(oa_bo->vma);
2167		goto out_ww;
2168	}
2169
2170	oa_bo->oa_config = i915_oa_config_get(oa_config);
2171	llist_add(&oa_bo->node, &stream->oa_config_bos);
2172
2173out_ww:
2174	if (err == -EDEADLK) {
2175		err = i915_gem_ww_ctx_backoff(&ww);
2176		if (!err)
2177			goto retry;
2178	}
2179	i915_gem_ww_ctx_fini(&ww);
2180
2181	if (err)
2182		i915_gem_object_put(obj);
2183err_free:
2184	if (err) {
2185		kfree(oa_bo);
2186		return ERR_PTR(err);
2187	}
2188	return oa_bo;
2189}
2190
2191static struct i915_vma *
2192get_oa_vma(struct i915_perf_stream *stream, struct i915_oa_config *oa_config)
2193{
2194	struct i915_oa_config_bo *oa_bo;
2195
2196	/*
2197	 * Look for the buffer in the already allocated BOs attached
2198	 * to the stream.
2199	 */
2200	llist_for_each_entry(oa_bo, stream->oa_config_bos.first, node) {
2201		if (oa_bo->oa_config == oa_config &&
2202		    memcmp(oa_bo->oa_config->uuid,
2203			   oa_config->uuid,
2204			   sizeof(oa_config->uuid)) == 0)
2205			goto out;
2206	}
2207
2208	oa_bo = alloc_oa_config_buffer(stream, oa_config);
2209	if (IS_ERR(oa_bo))
2210		return ERR_CAST(oa_bo);
2211
2212out:
2213	return i915_vma_get(oa_bo->vma);
2214}
2215
2216static int
2217emit_oa_config(struct i915_perf_stream *stream,
2218	       struct i915_oa_config *oa_config,
2219	       struct intel_context *ce,
2220	       struct i915_active *active)
2221{
2222	struct i915_request *rq;
2223	struct i915_vma *vma;
2224	struct i915_gem_ww_ctx ww;
2225	int err;
2226
2227	vma = get_oa_vma(stream, oa_config);
2228	if (IS_ERR(vma))
2229		return PTR_ERR(vma);
2230
2231	i915_gem_ww_ctx_init(&ww, true);
2232retry:
2233	err = i915_gem_object_lock(vma->obj, &ww);
2234	if (err)
2235		goto err;
2236
2237	err = i915_vma_pin_ww(vma, &ww, 0, 0, PIN_GLOBAL | PIN_HIGH);
2238	if (err)
2239		goto err;
2240
2241	intel_engine_pm_get(ce->engine);
2242	rq = i915_request_create(ce);
2243	intel_engine_pm_put(ce->engine);
2244	if (IS_ERR(rq)) {
2245		err = PTR_ERR(rq);
2246		goto err_vma_unpin;
2247	}
2248
2249	if (!IS_ERR_OR_NULL(active)) {
2250		/* After all individual context modifications */
2251		err = i915_request_await_active(rq, active,
2252						I915_ACTIVE_AWAIT_ACTIVE);
2253		if (err)
2254			goto err_add_request;
2255
2256		err = i915_active_add_request(active, rq);
2257		if (err)
2258			goto err_add_request;
2259	}
2260
2261	err = i915_vma_move_to_active(vma, rq, 0);
2262	if (err)
2263		goto err_add_request;
2264
2265	err = rq->engine->emit_bb_start(rq,
2266					vma->node.start, 0,
2267					I915_DISPATCH_SECURE);
2268	if (err)
2269		goto err_add_request;
2270
2271err_add_request:
2272	i915_request_add(rq);
2273err_vma_unpin:
2274	i915_vma_unpin(vma);
2275err:
2276	if (err == -EDEADLK) {
2277		err = i915_gem_ww_ctx_backoff(&ww);
2278		if (!err)
2279			goto retry;
2280	}
2281
2282	i915_gem_ww_ctx_fini(&ww);
2283	i915_vma_put(vma);
2284	return err;
2285}
2286
2287static struct intel_context *oa_context(struct i915_perf_stream *stream)
2288{
2289	return stream->pinned_ctx ?: stream->engine->kernel_context;
2290}
2291
2292static int
2293hsw_enable_metric_set(struct i915_perf_stream *stream,
2294		      struct i915_active *active)
2295{
2296	struct intel_uncore *uncore = stream->uncore;
2297
2298	/*
2299	 * PRM:
2300	 *
2301	 * OA unit is using “crclk” for its functionality. When trunk
2302	 * level clock gating takes place, OA clock would be gated,
2303	 * unable to count the events from non-render clock domain.
2304	 * Render clock gating must be disabled when OA is enabled to
2305	 * count the events from non-render domain. Unit level clock
2306	 * gating for RCS should also be disabled.
2307	 */
2308	intel_uncore_rmw(uncore, GEN7_MISCCPCTL,
2309			 GEN7_DOP_CLOCK_GATE_ENABLE, 0);
2310	intel_uncore_rmw(uncore, GEN6_UCGCTL1,
2311			 0, GEN6_CSUNIT_CLOCK_GATE_DISABLE);
2312
2313	return emit_oa_config(stream,
2314			      stream->oa_config, oa_context(stream),
2315			      active);
2316}
2317
2318static void hsw_disable_metric_set(struct i915_perf_stream *stream)
2319{
2320	struct intel_uncore *uncore = stream->uncore;
2321
2322	intel_uncore_rmw(uncore, GEN6_UCGCTL1,
2323			 GEN6_CSUNIT_CLOCK_GATE_DISABLE, 0);
2324	intel_uncore_rmw(uncore, GEN7_MISCCPCTL,
2325			 0, GEN7_DOP_CLOCK_GATE_ENABLE);
2326
2327	intel_uncore_rmw(uncore, GDT_CHICKEN_BITS, GT_NOA_ENABLE, 0);
2328}
2329
2330static u32 oa_config_flex_reg(const struct i915_oa_config *oa_config,
2331			      i915_reg_t reg)
2332{
2333	u32 mmio = i915_mmio_reg_offset(reg);
2334	int i;
2335
2336	/*
2337	 * This arbitrary default will select the 'EU FPU0 Pipeline
2338	 * Active' event. In the future it's anticipated that there
2339	 * will be an explicit 'No Event' we can select, but not yet...
2340	 */
2341	if (!oa_config)
2342		return 0;
2343
2344	for (i = 0; i < oa_config->flex_regs_len; i++) {
2345		if (i915_mmio_reg_offset(oa_config->flex_regs[i].addr) == mmio)
2346			return oa_config->flex_regs[i].value;
2347	}
2348
2349	return 0;
2350}
2351/*
2352 * NB: It must always remain pointer safe to run this even if the OA unit
2353 * has been disabled.
2354 *
2355 * It's fine to put out-of-date values into these per-context registers
2356 * in the case that the OA unit has been disabled.
2357 */
2358static void
2359gen8_update_reg_state_unlocked(const struct intel_context *ce,
2360			       const struct i915_perf_stream *stream)
2361{
2362	u32 ctx_oactxctrl = stream->perf->ctx_oactxctrl_offset;
2363	u32 ctx_flexeu0 = stream->perf->ctx_flexeu0_offset;
2364	/* The MMIO offsets for Flex EU registers aren't contiguous */
2365	static const i915_reg_t flex_regs[] = {
2366		EU_PERF_CNTL0,
2367		EU_PERF_CNTL1,
2368		EU_PERF_CNTL2,
2369		EU_PERF_CNTL3,
2370		EU_PERF_CNTL4,
2371		EU_PERF_CNTL5,
2372		EU_PERF_CNTL6,
2373	};
2374	u32 *reg_state = ce->lrc_reg_state;
2375	int i;
2376
2377	reg_state[ctx_oactxctrl + 1] =
2378		(stream->period_exponent << GEN8_OA_TIMER_PERIOD_SHIFT) |
2379		(stream->periodic ? GEN8_OA_TIMER_ENABLE : 0) |
2380		GEN8_OA_COUNTER_RESUME;
2381
2382	for (i = 0; i < ARRAY_SIZE(flex_regs); i++)
2383		reg_state[ctx_flexeu0 + i * 2 + 1] =
2384			oa_config_flex_reg(stream->oa_config, flex_regs[i]);
2385}
2386
2387struct flex {
2388	i915_reg_t reg;
2389	u32 offset;
2390	u32 value;
2391};
2392
2393static int
2394gen8_store_flex(struct i915_request *rq,
2395		struct intel_context *ce,
2396		const struct flex *flex, unsigned int count)
2397{
2398	u32 offset;
2399	u32 *cs;
2400
2401	cs = intel_ring_begin(rq, 4 * count);
2402	if (IS_ERR(cs))
2403		return PTR_ERR(cs);
2404
2405	offset = i915_ggtt_offset(ce->state) + LRC_STATE_OFFSET;
2406	do {
2407		*cs++ = MI_STORE_DWORD_IMM_GEN4 | MI_USE_GGTT;
2408		*cs++ = offset + flex->offset * sizeof(u32);
2409		*cs++ = 0;
2410		*cs++ = flex->value;
2411	} while (flex++, --count);
2412
2413	intel_ring_advance(rq, cs);
2414
2415	return 0;
2416}
2417
2418static int
2419gen8_load_flex(struct i915_request *rq,
2420	       struct intel_context *ce,
2421	       const struct flex *flex, unsigned int count)
2422{
2423	u32 *cs;
2424
2425	GEM_BUG_ON(!count || count > 63);
2426
2427	cs = intel_ring_begin(rq, 2 * count + 2);
2428	if (IS_ERR(cs))
2429		return PTR_ERR(cs);
2430
2431	*cs++ = MI_LOAD_REGISTER_IMM(count);
2432	do {
2433		*cs++ = i915_mmio_reg_offset(flex->reg);
2434		*cs++ = flex->value;
2435	} while (flex++, --count);
2436	*cs++ = MI_NOOP;
2437
2438	intel_ring_advance(rq, cs);
2439
2440	return 0;
2441}
2442
2443static int gen8_modify_context(struct intel_context *ce,
2444			       const struct flex *flex, unsigned int count)
2445{
2446	struct i915_request *rq;
2447	int err;
2448
2449	rq = intel_engine_create_kernel_request(ce->engine);
2450	if (IS_ERR(rq))
2451		return PTR_ERR(rq);
2452
2453	/* Serialise with the remote context */
2454	err = intel_context_prepare_remote_request(ce, rq);
2455	if (err == 0)
2456		err = gen8_store_flex(rq, ce, flex, count);
2457
2458	i915_request_add(rq);
2459	return err;
2460}
2461
2462static int
2463gen8_modify_self(struct intel_context *ce,
2464		 const struct flex *flex, unsigned int count,
2465		 struct i915_active *active)
2466{
2467	struct i915_request *rq;
2468	int err;
2469
2470	intel_engine_pm_get(ce->engine);
2471	rq = i915_request_create(ce);
2472	intel_engine_pm_put(ce->engine);
2473	if (IS_ERR(rq))
2474		return PTR_ERR(rq);
2475
2476	if (!IS_ERR_OR_NULL(active)) {
2477		err = i915_active_add_request(active, rq);
2478		if (err)
2479			goto err_add_request;
2480	}
2481
2482	err = gen8_load_flex(rq, ce, flex, count);
2483	if (err)
2484		goto err_add_request;
2485
2486err_add_request:
2487	i915_request_add(rq);
2488	return err;
2489}
2490
2491static int gen8_configure_context(struct i915_gem_context *ctx,
2492				  struct flex *flex, unsigned int count)
2493{
2494	struct i915_gem_engines_iter it;
2495	struct intel_context *ce;
2496	int err = 0;
2497
2498	for_each_gem_engine(ce, i915_gem_context_lock_engines(ctx), it) {
2499		GEM_BUG_ON(ce == ce->engine->kernel_context);
2500
2501		if (ce->engine->class != RENDER_CLASS)
2502			continue;
2503
2504		/* Otherwise OA settings will be set upon first use */
2505		if (!intel_context_pin_if_active(ce))
2506			continue;
2507
2508		flex->value = intel_sseu_make_rpcs(ce->engine->gt, &ce->sseu);
2509		err = gen8_modify_context(ce, flex, count);
2510
2511		intel_context_unpin(ce);
2512		if (err)
2513			break;
2514	}
2515	i915_gem_context_unlock_engines(ctx);
2516
2517	return err;
2518}
2519
2520static int gen12_configure_oar_context(struct i915_perf_stream *stream,
2521				       struct i915_active *active)
2522{
2523	int err;
2524	struct intel_context *ce = stream->pinned_ctx;
2525	u32 format = stream->oa_buffer.format->format;
2526	u32 offset = stream->perf->ctx_oactxctrl_offset;
2527	struct flex regs_context[] = {
2528		{
2529			GEN8_OACTXCONTROL,
2530			offset + 1,
2531			active ? GEN8_OA_COUNTER_RESUME : 0,
2532		},
2533	};
2534	/* Offsets in regs_lri are not used since this configuration is only
2535	 * applied using LRI. Initialize the correct offsets for posterity.
2536	 */
2537#define GEN12_OAR_OACONTROL_OFFSET 0x5B0
2538	struct flex regs_lri[] = {
2539		{
2540			GEN12_OAR_OACONTROL,
2541			GEN12_OAR_OACONTROL_OFFSET + 1,
2542			(format << GEN12_OAR_OACONTROL_COUNTER_FORMAT_SHIFT) |
2543			(active ? GEN12_OAR_OACONTROL_COUNTER_ENABLE : 0)
2544		},
2545		{
2546			RING_CONTEXT_CONTROL(ce->engine->mmio_base),
2547			CTX_CONTEXT_CONTROL,
2548			_MASKED_FIELD(GEN12_CTX_CTRL_OAR_CONTEXT_ENABLE,
2549				      active ?
2550				      GEN12_CTX_CTRL_OAR_CONTEXT_ENABLE :
2551				      0)
2552		},
2553	};
2554
2555	/* Modify the context image of pinned context with regs_context */
2556	err = intel_context_lock_pinned(ce);
2557	if (err)
2558		return err;
2559
2560	err = gen8_modify_context(ce, regs_context,
2561				  ARRAY_SIZE(regs_context));
2562	intel_context_unlock_pinned(ce);
2563	if (err)
2564		return err;
2565
2566	/* Apply regs_lri using LRI with pinned context */
2567	return gen8_modify_self(ce, regs_lri, ARRAY_SIZE(regs_lri), active);
2568}
2569
2570/*
2571 * Manages updating the per-context aspects of the OA stream
2572 * configuration across all contexts.
2573 *
2574 * The awkward consideration here is that OACTXCONTROL controls the
2575 * exponent for periodic sampling which is primarily used for system
2576 * wide profiling where we'd like a consistent sampling period even in
2577 * the face of context switches.
2578 *
2579 * Our approach of updating the register state context (as opposed to
2580 * say using a workaround batch buffer) ensures that the hardware
2581 * won't automatically reload an out-of-date timer exponent even
2582 * transiently before a WA BB could be parsed.
2583 *
2584 * This function needs to:
2585 * - Ensure the currently running context's per-context OA state is
2586 *   updated
2587 * - Ensure that all existing contexts will have the correct per-context
2588 *   OA state if they are scheduled for use.
2589 * - Ensure any new contexts will be initialized with the correct
2590 *   per-context OA state.
2591 *
2592 * Note: it's only the RCS/Render context that has any OA state.
2593 * Note: the first flex register passed must always be R_PWR_CLK_STATE
2594 */
2595static int
2596oa_configure_all_contexts(struct i915_perf_stream *stream,
2597			  struct flex *regs,
2598			  size_t num_regs,
2599			  struct i915_active *active)
2600{
2601	struct drm_i915_private *i915 = stream->perf->i915;
2602	struct intel_engine_cs *engine;
2603	struct intel_gt *gt = stream->engine->gt;
2604	struct i915_gem_context *ctx, *cn;
2605	int err;
2606
2607	lockdep_assert_held(&gt->perf.lock);
2608
2609	/*
2610	 * The OA register config is setup through the context image. This image
2611	 * might be written to by the GPU on context switch (in particular on
2612	 * lite-restore). This means we can't safely update a context's image,
2613	 * if this context is scheduled/submitted to run on the GPU.
2614	 *
2615	 * We could emit the OA register config through the batch buffer but
2616	 * this might leave small interval of time where the OA unit is
2617	 * configured at an invalid sampling period.
2618	 *
2619	 * Note that since we emit all requests from a single ring, there
2620	 * is still an implicit global barrier here that may cause a high
2621	 * priority context to wait for an otherwise independent low priority
2622	 * context. Contexts idle at the time of reconfiguration are not
2623	 * trapped behind the barrier.
2624	 */
2625	spin_lock(&i915->gem.contexts.lock);
2626	list_for_each_entry_safe(ctx, cn, &i915->gem.contexts.list, link) {
2627		if (!kref_get_unless_zero(&ctx->ref))
2628			continue;
2629
2630		spin_unlock(&i915->gem.contexts.lock);
2631
2632		err = gen8_configure_context(ctx, regs, num_regs);
2633		if (err) {
2634			i915_gem_context_put(ctx);
2635			return err;
2636		}
2637
2638		spin_lock(&i915->gem.contexts.lock);
2639		list_safe_reset_next(ctx, cn, link);
2640		i915_gem_context_put(ctx);
2641	}
2642	spin_unlock(&i915->gem.contexts.lock);
2643
2644	/*
2645	 * After updating all other contexts, we need to modify ourselves.
2646	 * If we don't modify the kernel_context, we do not get events while
2647	 * idle.
2648	 */
2649	for_each_uabi_engine(engine, i915) {
2650		struct intel_context *ce = engine->kernel_context;
2651
2652		if (engine->class != RENDER_CLASS)
2653			continue;
2654
2655		regs[0].value = intel_sseu_make_rpcs(engine->gt, &ce->sseu);
2656
2657		err = gen8_modify_self(ce, regs, num_regs, active);
2658		if (err)
2659			return err;
2660	}
2661
2662	return 0;
2663}
2664
2665static int
2666gen12_configure_all_contexts(struct i915_perf_stream *stream,
2667			     const struct i915_oa_config *oa_config,
2668			     struct i915_active *active)
2669{
2670	struct flex regs[] = {
2671		{
2672			GEN8_R_PWR_CLK_STATE(RENDER_RING_BASE),
2673			CTX_R_PWR_CLK_STATE,
2674		},
2675	};
2676
2677	return oa_configure_all_contexts(stream,
2678					 regs, ARRAY_SIZE(regs),
2679					 active);
2680}
2681
2682static int
2683lrc_configure_all_contexts(struct i915_perf_stream *stream,
2684			   const struct i915_oa_config *oa_config,
2685			   struct i915_active *active)
2686{
2687	u32 ctx_oactxctrl = stream->perf->ctx_oactxctrl_offset;
2688	/* The MMIO offsets for Flex EU registers aren't contiguous */
2689	const u32 ctx_flexeu0 = stream->perf->ctx_flexeu0_offset;
2690#define ctx_flexeuN(N) (ctx_flexeu0 + 2 * (N) + 1)
2691	struct flex regs[] = {
2692		{
2693			GEN8_R_PWR_CLK_STATE(RENDER_RING_BASE),
2694			CTX_R_PWR_CLK_STATE,
2695		},
2696		{
2697			GEN8_OACTXCONTROL,
2698			ctx_oactxctrl + 1,
2699		},
2700		{ EU_PERF_CNTL0, ctx_flexeuN(0) },
2701		{ EU_PERF_CNTL1, ctx_flexeuN(1) },
2702		{ EU_PERF_CNTL2, ctx_flexeuN(2) },
2703		{ EU_PERF_CNTL3, ctx_flexeuN(3) },
2704		{ EU_PERF_CNTL4, ctx_flexeuN(4) },
2705		{ EU_PERF_CNTL5, ctx_flexeuN(5) },
2706		{ EU_PERF_CNTL6, ctx_flexeuN(6) },
2707	};
2708#undef ctx_flexeuN
2709	int i;
2710
2711	regs[1].value =
2712		(stream->period_exponent << GEN8_OA_TIMER_PERIOD_SHIFT) |
2713		(stream->periodic ? GEN8_OA_TIMER_ENABLE : 0) |
2714		GEN8_OA_COUNTER_RESUME;
2715
2716	for (i = 2; i < ARRAY_SIZE(regs); i++)
2717		regs[i].value = oa_config_flex_reg(oa_config, regs[i].reg);
2718
2719	return oa_configure_all_contexts(stream,
2720					 regs, ARRAY_SIZE(regs),
2721					 active);
2722}
2723
2724static int
2725gen8_enable_metric_set(struct i915_perf_stream *stream,
2726		       struct i915_active *active)
2727{
2728	struct intel_uncore *uncore = stream->uncore;
2729	struct i915_oa_config *oa_config = stream->oa_config;
2730	int ret;
2731
2732	/*
2733	 * We disable slice/unslice clock ratio change reports on SKL since
2734	 * they are too noisy. The HW generates a lot of redundant reports
2735	 * where the ratio hasn't really changed causing a lot of redundant
2736	 * work to processes and increasing the chances we'll hit buffer
2737	 * overruns.
2738	 *
2739	 * Although we don't currently use the 'disable overrun' OABUFFER
2740	 * feature it's worth noting that clock ratio reports have to be
2741	 * disabled before considering to use that feature since the HW doesn't
2742	 * correctly block these reports.
2743	 *
2744	 * Currently none of the high-level metrics we have depend on knowing
2745	 * this ratio to normalize.
2746	 *
2747	 * Note: This register is not power context saved and restored, but
2748	 * that's OK considering that we disable RC6 while the OA unit is
2749	 * enabled.
2750	 *
2751	 * The _INCLUDE_CLK_RATIO bit allows the slice/unslice frequency to
2752	 * be read back from automatically triggered reports, as part of the
2753	 * RPT_ID field.
2754	 */
2755	if (IS_GRAPHICS_VER(stream->perf->i915, 9, 11)) {
2756		intel_uncore_write(uncore, GEN8_OA_DEBUG,
2757				   _MASKED_BIT_ENABLE(GEN9_OA_DEBUG_DISABLE_CLK_RATIO_REPORTS |
2758						      GEN9_OA_DEBUG_INCLUDE_CLK_RATIO));
2759	}
2760
2761	/*
2762	 * Update all contexts prior writing the mux configurations as we need
2763	 * to make sure all slices/subslices are ON before writing to NOA
2764	 * registers.
2765	 */
2766	ret = lrc_configure_all_contexts(stream, oa_config, active);
2767	if (ret)
2768		return ret;
2769
2770	return emit_oa_config(stream,
2771			      stream->oa_config, oa_context(stream),
2772			      active);
2773}
2774
2775static u32 oag_report_ctx_switches(const struct i915_perf_stream *stream)
2776{
2777	return _MASKED_FIELD(GEN12_OAG_OA_DEBUG_DISABLE_CTX_SWITCH_REPORTS,
2778			     (stream->sample_flags & SAMPLE_OA_REPORT) ?
2779			     0 : GEN12_OAG_OA_DEBUG_DISABLE_CTX_SWITCH_REPORTS);
2780}
2781
2782static int
2783gen12_enable_metric_set(struct i915_perf_stream *stream,
2784			struct i915_active *active)
2785{
2786	struct drm_i915_private *i915 = stream->perf->i915;
2787	struct intel_uncore *uncore = stream->uncore;
2788	struct i915_oa_config *oa_config = stream->oa_config;
2789	bool periodic = stream->periodic;
2790	u32 period_exponent = stream->period_exponent;
2791	u32 sqcnt1;
2792	int ret;
2793
2794	/*
2795	 * Wa_1508761755:xehpsdv, dg2
2796	 * EU NOA signals behave incorrectly if EU clock gating is enabled.
2797	 * Disable thread stall DOP gating and EU DOP gating.
2798	 */
2799	if (IS_XEHPSDV(i915) || IS_DG2(i915)) {
2800		intel_gt_mcr_multicast_write(uncore->gt, GEN8_ROW_CHICKEN,
2801					     _MASKED_BIT_ENABLE(STALL_DOP_GATING_DISABLE));
2802		intel_uncore_write(uncore, GEN7_ROW_CHICKEN2,
2803				   _MASKED_BIT_ENABLE(GEN12_DISABLE_DOP_GATING));
2804	}
2805
2806	intel_uncore_write(uncore, GEN12_OAG_OA_DEBUG,
2807			   /* Disable clk ratio reports, like previous Gens. */
2808			   _MASKED_BIT_ENABLE(GEN12_OAG_OA_DEBUG_DISABLE_CLK_RATIO_REPORTS |
2809					      GEN12_OAG_OA_DEBUG_INCLUDE_CLK_RATIO) |
2810			   /*
2811			    * If the user didn't require OA reports, instruct
2812			    * the hardware not to emit ctx switch reports.
2813			    */
2814			   oag_report_ctx_switches(stream));
2815
2816	intel_uncore_write(uncore, GEN12_OAG_OAGLBCTXCTRL, periodic ?
2817			   (GEN12_OAG_OAGLBCTXCTRL_COUNTER_RESUME |
2818			    GEN12_OAG_OAGLBCTXCTRL_TIMER_ENABLE |
2819			    (period_exponent << GEN12_OAG_OAGLBCTXCTRL_TIMER_PERIOD_SHIFT))
2820			    : 0);
2821
2822	/*
2823	 * Initialize Super Queue Internal Cnt Register
2824	 * Set PMON Enable in order to collect valid metrics.
2825	 * Enable byets per clock reporting in OA for XEHPSDV onward.
2826	 */
2827	sqcnt1 = GEN12_SQCNT1_PMON_ENABLE |
2828		 (HAS_OA_BPC_REPORTING(i915) ? GEN12_SQCNT1_OABPC : 0);
2829
2830	intel_uncore_rmw(uncore, GEN12_SQCNT1, 0, sqcnt1);
2831
2832	/*
2833	 * Update all contexts prior writing the mux configurations as we need
2834	 * to make sure all slices/subslices are ON before writing to NOA
2835	 * registers.
2836	 */
2837	ret = gen12_configure_all_contexts(stream, oa_config, active);
2838	if (ret)
2839		return ret;
2840
2841	/*
2842	 * For Gen12, performance counters are context
2843	 * saved/restored. Only enable it for the context that
2844	 * requested this.
2845	 */
2846	if (stream->ctx) {
2847		ret = gen12_configure_oar_context(stream, active);
2848		if (ret)
2849			return ret;
2850	}
2851
2852	return emit_oa_config(stream,
2853			      stream->oa_config, oa_context(stream),
2854			      active);
2855}
2856
2857static void gen8_disable_metric_set(struct i915_perf_stream *stream)
2858{
2859	struct intel_uncore *uncore = stream->uncore;
2860
2861	/* Reset all contexts' slices/subslices configurations. */
2862	lrc_configure_all_contexts(stream, NULL, NULL);
2863
2864	intel_uncore_rmw(uncore, GDT_CHICKEN_BITS, GT_NOA_ENABLE, 0);
2865}
2866
2867static void gen11_disable_metric_set(struct i915_perf_stream *stream)
2868{
2869	struct intel_uncore *uncore = stream->uncore;
2870
2871	/* Reset all contexts' slices/subslices configurations. */
2872	lrc_configure_all_contexts(stream, NULL, NULL);
2873
2874	/* Make sure we disable noa to save power. */
2875	intel_uncore_rmw(uncore, RPM_CONFIG1, GEN10_GT_NOA_ENABLE, 0);
2876}
2877
2878static void gen12_disable_metric_set(struct i915_perf_stream *stream)
2879{
2880	struct intel_uncore *uncore = stream->uncore;
2881	struct drm_i915_private *i915 = stream->perf->i915;
2882	u32 sqcnt1;
2883
2884	/*
2885	 * Wa_1508761755:xehpsdv, dg2
2886	 * Enable thread stall DOP gating and EU DOP gating.
2887	 */
2888	if (IS_XEHPSDV(i915) || IS_DG2(i915)) {
2889		intel_gt_mcr_multicast_write(uncore->gt, GEN8_ROW_CHICKEN,
2890					     _MASKED_BIT_DISABLE(STALL_DOP_GATING_DISABLE));
2891		intel_uncore_write(uncore, GEN7_ROW_CHICKEN2,
2892				   _MASKED_BIT_DISABLE(GEN12_DISABLE_DOP_GATING));
2893	}
2894
2895	/* Reset all contexts' slices/subslices configurations. */
2896	gen12_configure_all_contexts(stream, NULL, NULL);
2897
2898	/* disable the context save/restore or OAR counters */
2899	if (stream->ctx)
2900		gen12_configure_oar_context(stream, NULL);
2901
2902	/* Make sure we disable noa to save power. */
2903	intel_uncore_rmw(uncore, RPM_CONFIG1, GEN10_GT_NOA_ENABLE, 0);
2904
2905	sqcnt1 = GEN12_SQCNT1_PMON_ENABLE |
2906		 (HAS_OA_BPC_REPORTING(i915) ? GEN12_SQCNT1_OABPC : 0);
2907
2908	/* Reset PMON Enable to save power. */
2909	intel_uncore_rmw(uncore, GEN12_SQCNT1, sqcnt1, 0);
2910}
2911
2912static void gen7_oa_enable(struct i915_perf_stream *stream)
2913{
2914	struct intel_uncore *uncore = stream->uncore;
2915	struct i915_gem_context *ctx = stream->ctx;
2916	u32 ctx_id = stream->specific_ctx_id;
2917	bool periodic = stream->periodic;
2918	u32 period_exponent = stream->period_exponent;
2919	u32 report_format = stream->oa_buffer.format->format;
2920
2921	/*
2922	 * Reset buf pointers so we don't forward reports from before now.
2923	 *
2924	 * Think carefully if considering trying to avoid this, since it
2925	 * also ensures status flags and the buffer itself are cleared
2926	 * in error paths, and we have checks for invalid reports based
2927	 * on the assumption that certain fields are written to zeroed
2928	 * memory which this helps maintains.
2929	 */
2930	gen7_init_oa_buffer(stream);
2931
2932	intel_uncore_write(uncore, GEN7_OACONTROL,
2933			   (ctx_id & GEN7_OACONTROL_CTX_MASK) |
2934			   (period_exponent <<
2935			    GEN7_OACONTROL_TIMER_PERIOD_SHIFT) |
2936			   (periodic ? GEN7_OACONTROL_TIMER_ENABLE : 0) |
2937			   (report_format << GEN7_OACONTROL_FORMAT_SHIFT) |
2938			   (ctx ? GEN7_OACONTROL_PER_CTX_ENABLE : 0) |
2939			   GEN7_OACONTROL_ENABLE);
2940}
2941
2942static void gen8_oa_enable(struct i915_perf_stream *stream)
2943{
2944	struct intel_uncore *uncore = stream->uncore;
2945	u32 report_format = stream->oa_buffer.format->format;
2946
2947	/*
2948	 * Reset buf pointers so we don't forward reports from before now.
2949	 *
2950	 * Think carefully if considering trying to avoid this, since it
2951	 * also ensures status flags and the buffer itself are cleared
2952	 * in error paths, and we have checks for invalid reports based
2953	 * on the assumption that certain fields are written to zeroed
2954	 * memory which this helps maintains.
2955	 */
2956	gen8_init_oa_buffer(stream);
2957
2958	/*
2959	 * Note: we don't rely on the hardware to perform single context
2960	 * filtering and instead filter on the cpu based on the context-id
2961	 * field of reports
2962	 */
2963	intel_uncore_write(uncore, GEN8_OACONTROL,
2964			   (report_format << GEN8_OA_REPORT_FORMAT_SHIFT) |
2965			   GEN8_OA_COUNTER_ENABLE);
2966}
2967
2968static void gen12_oa_enable(struct i915_perf_stream *stream)
2969{
2970	struct intel_uncore *uncore = stream->uncore;
2971	u32 report_format = stream->oa_buffer.format->format;
2972
2973	/*
2974	 * If we don't want OA reports from the OA buffer, then we don't even
2975	 * need to program the OAG unit.
2976	 */
2977	if (!(stream->sample_flags & SAMPLE_OA_REPORT))
2978		return;
2979
2980	gen12_init_oa_buffer(stream);
2981
2982	intel_uncore_write(uncore, GEN12_OAG_OACONTROL,
2983			   (report_format << GEN12_OAG_OACONTROL_OA_COUNTER_FORMAT_SHIFT) |
2984			   GEN12_OAG_OACONTROL_OA_COUNTER_ENABLE);
2985}
2986
2987/**
2988 * i915_oa_stream_enable - handle `I915_PERF_IOCTL_ENABLE` for OA stream
2989 * @stream: An i915 perf stream opened for OA metrics
2990 *
2991 * [Re]enables hardware periodic sampling according to the period configured
2992 * when opening the stream. This also starts a hrtimer that will periodically
2993 * check for data in the circular OA buffer for notifying userspace (e.g.
2994 * during a read() or poll()).
2995 */
2996static void i915_oa_stream_enable(struct i915_perf_stream *stream)
2997{
2998	stream->pollin = false;
2999
3000	stream->perf->ops.oa_enable(stream);
3001
3002	if (stream->sample_flags & SAMPLE_OA_REPORT)
3003		hrtimer_start(&stream->poll_check_timer,
3004			      ns_to_ktime(stream->poll_oa_period),
3005			      HRTIMER_MODE_REL_PINNED);
3006}
3007
3008static void gen7_oa_disable(struct i915_perf_stream *stream)
3009{
3010	struct intel_uncore *uncore = stream->uncore;
3011
3012	intel_uncore_write(uncore, GEN7_OACONTROL, 0);
3013	if (intel_wait_for_register(uncore,
3014				    GEN7_OACONTROL, GEN7_OACONTROL_ENABLE, 0,
3015				    50))
3016		drm_err(&stream->perf->i915->drm,
3017			"wait for OA to be disabled timed out\n");
3018}
3019
3020static void gen8_oa_disable(struct i915_perf_stream *stream)
3021{
3022	struct intel_uncore *uncore = stream->uncore;
3023
3024	intel_uncore_write(uncore, GEN8_OACONTROL, 0);
3025	if (intel_wait_for_register(uncore,
3026				    GEN8_OACONTROL, GEN8_OA_COUNTER_ENABLE, 0,
3027				    50))
3028		drm_err(&stream->perf->i915->drm,
3029			"wait for OA to be disabled timed out\n");
3030}
3031
3032static void gen12_oa_disable(struct i915_perf_stream *stream)
3033{
3034	struct intel_uncore *uncore = stream->uncore;
3035
3036	intel_uncore_write(uncore, GEN12_OAG_OACONTROL, 0);
3037	if (intel_wait_for_register(uncore,
3038				    GEN12_OAG_OACONTROL,
3039				    GEN12_OAG_OACONTROL_OA_COUNTER_ENABLE, 0,
3040				    50))
3041		drm_err(&stream->perf->i915->drm,
3042			"wait for OA to be disabled timed out\n");
3043
3044	intel_uncore_write(uncore, GEN12_OA_TLB_INV_CR, 1);
3045	if (intel_wait_for_register(uncore,
3046				    GEN12_OA_TLB_INV_CR,
3047				    1, 0,
3048				    50))
3049		drm_err(&stream->perf->i915->drm,
3050			"wait for OA tlb invalidate timed out\n");
3051}
3052
3053/**
3054 * i915_oa_stream_disable - handle `I915_PERF_IOCTL_DISABLE` for OA stream
3055 * @stream: An i915 perf stream opened for OA metrics
3056 *
3057 * Stops the OA unit from periodically writing counter reports into the
3058 * circular OA buffer. This also stops the hrtimer that periodically checks for
3059 * data in the circular OA buffer, for notifying userspace.
3060 */
3061static void i915_oa_stream_disable(struct i915_perf_stream *stream)
3062{
3063	stream->perf->ops.oa_disable(stream);
3064
3065	if (stream->sample_flags & SAMPLE_OA_REPORT)
3066		hrtimer_cancel(&stream->poll_check_timer);
3067}
3068
3069static const struct i915_perf_stream_ops i915_oa_stream_ops = {
3070	.destroy = i915_oa_stream_destroy,
3071	.enable = i915_oa_stream_enable,
3072	.disable = i915_oa_stream_disable,
3073	.wait_unlocked = i915_oa_wait_unlocked,
3074	.poll_wait = i915_oa_poll_wait,
3075	.read = i915_oa_read,
3076};
3077
3078static int i915_perf_stream_enable_sync(struct i915_perf_stream *stream)
3079{
3080	struct i915_active *active;
3081	int err;
3082
3083	active = i915_active_create();
3084	if (!active)
3085		return -ENOMEM;
3086
3087	err = stream->perf->ops.enable_metric_set(stream, active);
3088	if (err == 0)
3089		__i915_active_wait(active, TASK_UNINTERRUPTIBLE);
3090
3091	i915_active_put(active);
3092	return err;
3093}
3094
3095static void
3096get_default_sseu_config(struct intel_sseu *out_sseu,
3097			struct intel_engine_cs *engine)
3098{
3099	const struct sseu_dev_info *devinfo_sseu = &engine->gt->info.sseu;
3100
3101	*out_sseu = intel_sseu_from_device_info(devinfo_sseu);
3102
3103	if (GRAPHICS_VER(engine->i915) == 11) {
3104		/*
3105		 * We only need subslice count so it doesn't matter which ones
3106		 * we select - just turn off low bits in the amount of half of
3107		 * all available subslices per slice.
3108		 */
3109		out_sseu->subslice_mask =
3110			~(~0 << (hweight8(out_sseu->subslice_mask) / 2));
3111		out_sseu->slice_mask = 0x1;
3112	}
3113}
3114
3115static int
3116get_sseu_config(struct intel_sseu *out_sseu,
3117		struct intel_engine_cs *engine,
3118		const struct drm_i915_gem_context_param_sseu *drm_sseu)
3119{
3120	if (drm_sseu->engine.engine_class != engine->uabi_class ||
3121	    drm_sseu->engine.engine_instance != engine->uabi_instance)
3122		return -EINVAL;
3123
3124	return i915_gem_user_to_context_sseu(engine->gt, drm_sseu, out_sseu);
3125}
3126
3127/*
3128 * OA timestamp frequency = CS timestamp frequency in most platforms. On some
3129 * platforms OA unit ignores the CTC_SHIFT and the 2 timestamps differ. In such
3130 * cases, return the adjusted CS timestamp frequency to the user.
3131 */
3132u32 i915_perf_oa_timestamp_frequency(struct drm_i915_private *i915)
3133{
3134	/* Wa_18013179988:dg2 */
3135	if (IS_DG2(i915)) {
3136		intel_wakeref_t wakeref;
3137		u32 reg, shift;
3138
3139		with_intel_runtime_pm(to_gt(i915)->uncore->rpm, wakeref)
3140			reg = intel_uncore_read(to_gt(i915)->uncore, RPM_CONFIG0);
3141
3142		shift = REG_FIELD_GET(GEN10_RPM_CONFIG0_CTC_SHIFT_PARAMETER_MASK,
3143				      reg);
3144
3145		return to_gt(i915)->clock_frequency << (3 - shift);
3146	}
3147
3148	return to_gt(i915)->clock_frequency;
3149}
3150
3151/**
3152 * i915_oa_stream_init - validate combined props for OA stream and init
3153 * @stream: An i915 perf stream
3154 * @param: The open parameters passed to `DRM_I915_PERF_OPEN`
3155 * @props: The property state that configures stream (individually validated)
3156 *
3157 * While read_properties_unlocked() validates properties in isolation it
3158 * doesn't ensure that the combination necessarily makes sense.
3159 *
3160 * At this point it has been determined that userspace wants a stream of
3161 * OA metrics, but still we need to further validate the combined
3162 * properties are OK.
3163 *
3164 * If the configuration makes sense then we can allocate memory for
3165 * a circular OA buffer and apply the requested metric set configuration.
3166 *
3167 * Returns: zero on success or a negative error code.
3168 */
3169static int i915_oa_stream_init(struct i915_perf_stream *stream,
3170			       struct drm_i915_perf_open_param *param,
3171			       struct perf_open_properties *props)
3172{
3173	struct drm_i915_private *i915 = stream->perf->i915;
3174	struct i915_perf *perf = stream->perf;
3175	struct intel_gt *gt;
3176	int ret;
3177
3178	if (!props->engine) {
3179		drm_dbg(&stream->perf->i915->drm,
3180			"OA engine not specified\n");
3181		return -EINVAL;
3182	}
3183	gt = props->engine->gt;
3184
3185	/*
3186	 * If the sysfs metrics/ directory wasn't registered for some
3187	 * reason then don't let userspace try their luck with config
3188	 * IDs
3189	 */
3190	if (!perf->metrics_kobj) {
3191		drm_dbg(&stream->perf->i915->drm,
3192			"OA metrics weren't advertised via sysfs\n");
3193		return -EINVAL;
3194	}
3195
3196	if (!(props->sample_flags & SAMPLE_OA_REPORT) &&
3197	    (GRAPHICS_VER(perf->i915) < 12 || !stream->ctx)) {
3198		drm_dbg(&stream->perf->i915->drm,
3199			"Only OA report sampling supported\n");
3200		return -EINVAL;
3201	}
3202
3203	if (!perf->ops.enable_metric_set) {
3204		drm_dbg(&stream->perf->i915->drm,
3205			"OA unit not supported\n");
3206		return -ENODEV;
3207	}
3208
3209	/*
3210	 * To avoid the complexity of having to accurately filter
3211	 * counter reports and marshal to the appropriate client
3212	 * we currently only allow exclusive access
3213	 */
3214	if (gt->perf.exclusive_stream) {
3215		drm_dbg(&stream->perf->i915->drm,
3216			"OA unit already in use\n");
3217		return -EBUSY;
3218	}
3219
3220	if (!props->oa_format) {
3221		drm_dbg(&stream->perf->i915->drm,
3222			"OA report format not specified\n");
3223		return -EINVAL;
3224	}
3225
3226	stream->engine = props->engine;
3227	stream->uncore = stream->engine->gt->uncore;
3228
3229	stream->sample_size = sizeof(struct drm_i915_perf_record_header);
3230
3231	stream->oa_buffer.format = &perf->oa_formats[props->oa_format];
3232	if (drm_WARN_ON(&i915->drm, stream->oa_buffer.format->size == 0))
3233		return -EINVAL;
3234
3235	stream->sample_flags = props->sample_flags;
3236	stream->sample_size += stream->oa_buffer.format->size;
3237
3238	stream->hold_preemption = props->hold_preemption;
3239
3240	stream->periodic = props->oa_periodic;
3241	if (stream->periodic)
3242		stream->period_exponent = props->oa_period_exponent;
3243
3244	if (stream->ctx) {
3245		ret = oa_get_render_ctx_id(stream);
3246		if (ret) {
3247			drm_dbg(&stream->perf->i915->drm,
3248				"Invalid context id to filter with\n");
3249			return ret;
3250		}
3251	}
3252
3253	ret = alloc_noa_wait(stream);
3254	if (ret) {
3255		drm_dbg(&stream->perf->i915->drm,
3256			"Unable to allocate NOA wait batch buffer\n");
3257		goto err_noa_wait_alloc;
3258	}
3259
3260	stream->oa_config = i915_perf_get_oa_config(perf, props->metrics_set);
3261	if (!stream->oa_config) {
3262		drm_dbg(&stream->perf->i915->drm,
3263			"Invalid OA config id=%i\n", props->metrics_set);
3264		ret = -EINVAL;
3265		goto err_config;
3266	}
3267
3268	/* PRM - observability performance counters:
3269	 *
3270	 *   OACONTROL, performance counter enable, note:
3271	 *
3272	 *   "When this bit is set, in order to have coherent counts,
3273	 *   RC6 power state and trunk clock gating must be disabled.
3274	 *   This can be achieved by programming MMIO registers as
3275	 *   0xA094=0 and 0xA090[31]=1"
3276	 *
3277	 *   In our case we are expecting that taking pm + FORCEWAKE
3278	 *   references will effectively disable RC6.
3279	 */
3280	intel_engine_pm_get(stream->engine);
3281	intel_uncore_forcewake_get(stream->uncore, FORCEWAKE_ALL);
3282
3283	/*
3284	 * Wa_16011777198:dg2: GuC resets render as part of the Wa. This causes
3285	 * OA to lose the configuration state. Prevent this by overriding GUCRC
3286	 * mode.
3287	 */
3288	if (intel_uc_uses_guc_rc(&gt->uc) &&
3289	    (IS_DG2_GRAPHICS_STEP(gt->i915, G10, STEP_A0, STEP_C0) ||
3290	     IS_DG2_GRAPHICS_STEP(gt->i915, G11, STEP_A0, STEP_B0))) {
3291		ret = intel_guc_slpc_override_gucrc_mode(&gt->uc.guc.slpc,
3292							 SLPC_GUCRC_MODE_GUCRC_NO_RC6);
3293		if (ret) {
3294			drm_dbg(&stream->perf->i915->drm,
3295				"Unable to override gucrc mode\n");
3296			goto err_config;
3297		}
3298	}
3299
3300	ret = alloc_oa_buffer(stream);
3301	if (ret)
3302		goto err_oa_buf_alloc;
3303
3304	stream->ops = &i915_oa_stream_ops;
3305
3306	stream->engine->gt->perf.sseu = props->sseu;
3307	WRITE_ONCE(gt->perf.exclusive_stream, stream);
3308
3309	ret = i915_perf_stream_enable_sync(stream);
3310	if (ret) {
3311		drm_dbg(&stream->perf->i915->drm,
3312			"Unable to enable metric set\n");
3313		goto err_enable;
3314	}
3315
3316	drm_dbg(&stream->perf->i915->drm,
3317		"opening stream oa config uuid=%s\n",
3318		  stream->oa_config->uuid);
3319
3320	hrtimer_init(&stream->poll_check_timer,
3321		     CLOCK_MONOTONIC, HRTIMER_MODE_REL);
3322	stream->poll_check_timer.function = oa_poll_check_timer_cb;
3323	init_waitqueue_head(&stream->poll_wq);
3324	spin_lock_init(&stream->oa_buffer.ptr_lock);
3325	mutex_init(&stream->lock);
3326
3327	return 0;
3328
3329err_enable:
3330	WRITE_ONCE(gt->perf.exclusive_stream, NULL);
3331	perf->ops.disable_metric_set(stream);
3332
3333	free_oa_buffer(stream);
3334
3335err_oa_buf_alloc:
3336	free_oa_configs(stream);
3337
3338	intel_uncore_forcewake_put(stream->uncore, FORCEWAKE_ALL);
3339	intel_engine_pm_put(stream->engine);
3340
3341err_config:
3342	free_noa_wait(stream);
3343
3344err_noa_wait_alloc:
3345	if (stream->ctx)
3346		oa_put_render_ctx_id(stream);
3347
3348	return ret;
3349}
3350
3351void i915_oa_init_reg_state(const struct intel_context *ce,
3352			    const struct intel_engine_cs *engine)
3353{
3354	struct i915_perf_stream *stream;
3355
3356	if (engine->class != RENDER_CLASS)
3357		return;
3358
3359	/* perf.exclusive_stream serialised by lrc_configure_all_contexts() */
3360	stream = READ_ONCE(engine->gt->perf.exclusive_stream);
3361	if (stream && GRAPHICS_VER(stream->perf->i915) < 12)
3362		gen8_update_reg_state_unlocked(ce, stream);
3363}
3364
3365/**
3366 * i915_perf_read - handles read() FOP for i915 perf stream FDs
3367 * @file: An i915 perf stream file
3368 * @buf: destination buffer given by userspace
3369 * @count: the number of bytes userspace wants to read
3370 * @ppos: (inout) file seek position (unused)
3371 *
3372 * The entry point for handling a read() on a stream file descriptor from
3373 * userspace. Most of the work is left to the i915_perf_read_locked() and
3374 * &i915_perf_stream_ops->read but to save having stream implementations (of
3375 * which we might have multiple later) we handle blocking read here.
3376 *
3377 * We can also consistently treat trying to read from a disabled stream
3378 * as an IO error so implementations can assume the stream is enabled
3379 * while reading.
3380 *
3381 * Returns: The number of bytes copied or a negative error code on failure.
3382 */
3383static ssize_t i915_perf_read(struct file *file,
3384			      char __user *buf,
3385			      size_t count,
3386			      loff_t *ppos)
3387{
3388	struct i915_perf_stream *stream = file->private_data;
3389	size_t offset = 0;
3390	int ret;
3391
3392	/* To ensure it's handled consistently we simply treat all reads of a
3393	 * disabled stream as an error. In particular it might otherwise lead
3394	 * to a deadlock for blocking file descriptors...
3395	 */
3396	if (!stream->enabled || !(stream->sample_flags & SAMPLE_OA_REPORT))
3397		return -EIO;
3398
3399	if (!(file->f_flags & O_NONBLOCK)) {
3400		/* There's the small chance of false positives from
3401		 * stream->ops->wait_unlocked.
3402		 *
3403		 * E.g. with single context filtering since we only wait until
3404		 * oabuffer has >= 1 report we don't immediately know whether
3405		 * any reports really belong to the current context
3406		 */
3407		do {
3408			ret = stream->ops->wait_unlocked(stream);
3409			if (ret)
3410				return ret;
3411
3412			mutex_lock(&stream->lock);
3413			ret = stream->ops->read(stream, buf, count, &offset);
3414			mutex_unlock(&stream->lock);
3415		} while (!offset && !ret);
3416	} else {
3417		mutex_lock(&stream->lock);
3418		ret = stream->ops->read(stream, buf, count, &offset);
3419		mutex_unlock(&stream->lock);
3420	}
3421
3422	/* We allow the poll checking to sometimes report false positive EPOLLIN
3423	 * events where we might actually report EAGAIN on read() if there's
3424	 * not really any data available. In this situation though we don't
3425	 * want to enter a busy loop between poll() reporting a EPOLLIN event
3426	 * and read() returning -EAGAIN. Clearing the oa.pollin state here
3427	 * effectively ensures we back off until the next hrtimer callback
3428	 * before reporting another EPOLLIN event.
3429	 * The exception to this is if ops->read() returned -ENOSPC which means
3430	 * that more OA data is available than could fit in the user provided
3431	 * buffer. In this case we want the next poll() call to not block.
3432	 */
3433	if (ret != -ENOSPC)
3434		stream->pollin = false;
3435
3436	/* Possible values for ret are 0, -EFAULT, -ENOSPC, -EIO, ... */
3437	return offset ?: (ret ?: -EAGAIN);
3438}
3439
3440static enum hrtimer_restart oa_poll_check_timer_cb(struct hrtimer *hrtimer)
3441{
3442	struct i915_perf_stream *stream =
3443		container_of(hrtimer, typeof(*stream), poll_check_timer);
3444
3445	if (oa_buffer_check_unlocked(stream)) {
3446		stream->pollin = true;
3447		wake_up(&stream->poll_wq);
3448	}
3449
3450	hrtimer_forward_now(hrtimer,
3451			    ns_to_ktime(stream->poll_oa_period));
3452
3453	return HRTIMER_RESTART;
3454}
3455
3456/**
3457 * i915_perf_poll_locked - poll_wait() with a suitable wait queue for stream
3458 * @stream: An i915 perf stream
3459 * @file: An i915 perf stream file
3460 * @wait: poll() state table
3461 *
3462 * For handling userspace polling on an i915 perf stream, this calls through to
3463 * &i915_perf_stream_ops->poll_wait to call poll_wait() with a wait queue that
3464 * will be woken for new stream data.
3465 *
3466 * Returns: any poll events that are ready without sleeping
3467 */
3468static __poll_t i915_perf_poll_locked(struct i915_perf_stream *stream,
3469				      struct file *file,
3470				      poll_table *wait)
3471{
3472	__poll_t events = 0;
3473
3474	stream->ops->poll_wait(stream, file, wait);
3475
3476	/* Note: we don't explicitly check whether there's something to read
3477	 * here since this path may be very hot depending on what else
3478	 * userspace is polling, or on the timeout in use. We rely solely on
3479	 * the hrtimer/oa_poll_check_timer_cb to notify us when there are
3480	 * samples to read.
3481	 */
3482	if (stream->pollin)
3483		events |= EPOLLIN;
3484
3485	return events;
3486}
3487
3488/**
3489 * i915_perf_poll - call poll_wait() with a suitable wait queue for stream
3490 * @file: An i915 perf stream file
3491 * @wait: poll() state table
3492 *
3493 * For handling userspace polling on an i915 perf stream, this ensures
3494 * poll_wait() gets called with a wait queue that will be woken for new stream
3495 * data.
3496 *
3497 * Note: Implementation deferred to i915_perf_poll_locked()
3498 *
3499 * Returns: any poll events that are ready without sleeping
3500 */
3501static __poll_t i915_perf_poll(struct file *file, poll_table *wait)
3502{
3503	struct i915_perf_stream *stream = file->private_data;
3504	__poll_t ret;
3505
3506	mutex_lock(&stream->lock);
3507	ret = i915_perf_poll_locked(stream, file, wait);
3508	mutex_unlock(&stream->lock);
3509
3510	return ret;
3511}
3512
3513/**
3514 * i915_perf_enable_locked - handle `I915_PERF_IOCTL_ENABLE` ioctl
3515 * @stream: A disabled i915 perf stream
3516 *
3517 * [Re]enables the associated capture of data for this stream.
3518 *
3519 * If a stream was previously enabled then there's currently no intention
3520 * to provide userspace any guarantee about the preservation of previously
3521 * buffered data.
3522 */
3523static void i915_perf_enable_locked(struct i915_perf_stream *stream)
3524{
3525	if (stream->enabled)
3526		return;
3527
3528	/* Allow stream->ops->enable() to refer to this */
3529	stream->enabled = true;
3530
3531	if (stream->ops->enable)
3532		stream->ops->enable(stream);
3533
3534	if (stream->hold_preemption)
3535		intel_context_set_nopreempt(stream->pinned_ctx);
3536}
3537
3538/**
3539 * i915_perf_disable_locked - handle `I915_PERF_IOCTL_DISABLE` ioctl
3540 * @stream: An enabled i915 perf stream
3541 *
3542 * Disables the associated capture of data for this stream.
3543 *
3544 * The intention is that disabling an re-enabling a stream will ideally be
3545 * cheaper than destroying and re-opening a stream with the same configuration,
3546 * though there are no formal guarantees about what state or buffered data
3547 * must be retained between disabling and re-enabling a stream.
3548 *
3549 * Note: while a stream is disabled it's considered an error for userspace
3550 * to attempt to read from the stream (-EIO).
3551 */
3552static void i915_perf_disable_locked(struct i915_perf_stream *stream)
3553{
3554	if (!stream->enabled)
3555		return;
3556
3557	/* Allow stream->ops->disable() to refer to this */
3558	stream->enabled = false;
3559
3560	if (stream->hold_preemption)
3561		intel_context_clear_nopreempt(stream->pinned_ctx);
3562
3563	if (stream->ops->disable)
3564		stream->ops->disable(stream);
3565}
3566
3567static long i915_perf_config_locked(struct i915_perf_stream *stream,
3568				    unsigned long metrics_set)
3569{
3570	struct i915_oa_config *config;
3571	long ret = stream->oa_config->id;
3572
3573	config = i915_perf_get_oa_config(stream->perf, metrics_set);
3574	if (!config)
3575		return -EINVAL;
3576
3577	if (config != stream->oa_config) {
3578		int err;
3579
3580		/*
3581		 * If OA is bound to a specific context, emit the
3582		 * reconfiguration inline from that context. The update
3583		 * will then be ordered with respect to submission on that
3584		 * context.
3585		 *
3586		 * When set globally, we use a low priority kernel context,
3587		 * so it will effectively take effect when idle.
3588		 */
3589		err = emit_oa_config(stream, config, oa_context(stream), NULL);
3590		if (!err)
3591			config = xchg(&stream->oa_config, config);
3592		else
3593			ret = err;
3594	}
3595
3596	i915_oa_config_put(config);
3597
3598	return ret;
3599}
3600
3601/**
3602 * i915_perf_ioctl_locked - support ioctl() usage with i915 perf stream FDs
3603 * @stream: An i915 perf stream
3604 * @cmd: the ioctl request
3605 * @arg: the ioctl data
3606 *
3607 * Returns: zero on success or a negative error code. Returns -EINVAL for
3608 * an unknown ioctl request.
3609 */
3610static long i915_perf_ioctl_locked(struct i915_perf_stream *stream,
3611				   unsigned int cmd,
3612				   unsigned long arg)
3613{
3614	switch (cmd) {
3615	case I915_PERF_IOCTL_ENABLE:
3616		i915_perf_enable_locked(stream);
3617		return 0;
3618	case I915_PERF_IOCTL_DISABLE:
3619		i915_perf_disable_locked(stream);
3620		return 0;
3621	case I915_PERF_IOCTL_CONFIG:
3622		return i915_perf_config_locked(stream, arg);
3623	}
3624
3625	return -EINVAL;
3626}
3627
3628/**
3629 * i915_perf_ioctl - support ioctl() usage with i915 perf stream FDs
3630 * @file: An i915 perf stream file
3631 * @cmd: the ioctl request
3632 * @arg: the ioctl data
3633 *
3634 * Implementation deferred to i915_perf_ioctl_locked().
3635 *
3636 * Returns: zero on success or a negative error code. Returns -EINVAL for
3637 * an unknown ioctl request.
3638 */
3639static long i915_perf_ioctl(struct file *file,
3640			    unsigned int cmd,
3641			    unsigned long arg)
3642{
3643	struct i915_perf_stream *stream = file->private_data;
3644	long ret;
3645
3646	mutex_lock(&stream->lock);
3647	ret = i915_perf_ioctl_locked(stream, cmd, arg);
3648	mutex_unlock(&stream->lock);
3649
3650	return ret;
3651}
3652
3653/**
3654 * i915_perf_destroy_locked - destroy an i915 perf stream
3655 * @stream: An i915 perf stream
3656 *
3657 * Frees all resources associated with the given i915 perf @stream, disabling
3658 * any associated data capture in the process.
3659 *
3660 * Note: The &gt->perf.lock mutex has been taken to serialize
3661 * with any non-file-operation driver hooks.
3662 */
3663static void i915_perf_destroy_locked(struct i915_perf_stream *stream)
3664{
3665	if (stream->enabled)
3666		i915_perf_disable_locked(stream);
3667
3668	if (stream->ops->destroy)
3669		stream->ops->destroy(stream);
3670
3671	if (stream->ctx)
3672		i915_gem_context_put(stream->ctx);
3673
3674	kfree(stream);
3675}
3676
3677/**
3678 * i915_perf_release - handles userspace close() of a stream file
3679 * @inode: anonymous inode associated with file
3680 * @file: An i915 perf stream file
3681 *
3682 * Cleans up any resources associated with an open i915 perf stream file.
3683 *
3684 * NB: close() can't really fail from the userspace point of view.
3685 *
3686 * Returns: zero on success or a negative error code.
3687 */
3688static int i915_perf_release(struct inode *inode, struct file *file)
3689{
3690	struct i915_perf_stream *stream = file->private_data;
3691	struct i915_perf *perf = stream->perf;
3692	struct intel_gt *gt = stream->engine->gt;
3693
3694	/*
3695	 * Within this call, we know that the fd is being closed and we have no
3696	 * other user of stream->lock. Use the perf lock to destroy the stream
3697	 * here.
3698	 */
3699	mutex_lock(&gt->perf.lock);
3700	i915_perf_destroy_locked(stream);
3701	mutex_unlock(&gt->perf.lock);
3702
3703	/* Release the reference the perf stream kept on the driver. */
3704	drm_dev_put(&perf->i915->drm);
3705
3706	return 0;
3707}
3708
3709
3710static const struct file_operations fops = {
3711	.owner		= THIS_MODULE,
3712	.llseek		= no_llseek,
3713	.release	= i915_perf_release,
3714	.poll		= i915_perf_poll,
3715	.read		= i915_perf_read,
3716	.unlocked_ioctl	= i915_perf_ioctl,
3717	/* Our ioctl have no arguments, so it's safe to use the same function
3718	 * to handle 32bits compatibility.
3719	 */
3720	.compat_ioctl   = i915_perf_ioctl,
3721};
3722
3723
3724/**
3725 * i915_perf_open_ioctl_locked - DRM ioctl() for userspace to open a stream FD
3726 * @perf: i915 perf instance
3727 * @param: The open parameters passed to 'DRM_I915_PERF_OPEN`
3728 * @props: individually validated u64 property value pairs
3729 * @file: drm file
3730 *
3731 * See i915_perf_ioctl_open() for interface details.
3732 *
3733 * Implements further stream config validation and stream initialization on
3734 * behalf of i915_perf_open_ioctl() with the &gt->perf.lock mutex
3735 * taken to serialize with any non-file-operation driver hooks.
3736 *
3737 * Note: at this point the @props have only been validated in isolation and
3738 * it's still necessary to validate that the combination of properties makes
3739 * sense.
3740 *
3741 * In the case where userspace is interested in OA unit metrics then further
3742 * config validation and stream initialization details will be handled by
3743 * i915_oa_stream_init(). The code here should only validate config state that
3744 * will be relevant to all stream types / backends.
3745 *
3746 * Returns: zero on success or a negative error code.
3747 */
3748static int
3749i915_perf_open_ioctl_locked(struct i915_perf *perf,
3750			    struct drm_i915_perf_open_param *param,
3751			    struct perf_open_properties *props,
3752			    struct drm_file *file)
3753{
3754	struct i915_gem_context *specific_ctx = NULL;
3755	struct i915_perf_stream *stream = NULL;
3756	unsigned long f_flags = 0;
3757	bool privileged_op = true;
3758	int stream_fd;
3759	int ret;
3760
3761	if (props->single_context) {
3762		u32 ctx_handle = props->ctx_handle;
3763		struct drm_i915_file_private *file_priv = file->driver_priv;
3764
3765		specific_ctx = i915_gem_context_lookup(file_priv, ctx_handle);
3766		if (IS_ERR(specific_ctx)) {
3767			drm_dbg(&perf->i915->drm,
3768				"Failed to look up context with ID %u for opening perf stream\n",
3769				  ctx_handle);
3770			ret = PTR_ERR(specific_ctx);
3771			goto err;
3772		}
3773	}
3774
3775	/*
3776	 * On Haswell the OA unit supports clock gating off for a specific
3777	 * context and in this mode there's no visibility of metrics for the
3778	 * rest of the system, which we consider acceptable for a
3779	 * non-privileged client.
3780	 *
3781	 * For Gen8->11 the OA unit no longer supports clock gating off for a
3782	 * specific context and the kernel can't securely stop the counters
3783	 * from updating as system-wide / global values. Even though we can
3784	 * filter reports based on the included context ID we can't block
3785	 * clients from seeing the raw / global counter values via
3786	 * MI_REPORT_PERF_COUNT commands and so consider it a privileged op to
3787	 * enable the OA unit by default.
3788	 *
3789	 * For Gen12+ we gain a new OAR unit that only monitors the RCS on a
3790	 * per context basis. So we can relax requirements there if the user
3791	 * doesn't request global stream access (i.e. query based sampling
3792	 * using MI_RECORD_PERF_COUNT.
3793	 */
3794	if (IS_HASWELL(perf->i915) && specific_ctx)
3795		privileged_op = false;
3796	else if (GRAPHICS_VER(perf->i915) == 12 && specific_ctx &&
3797		 (props->sample_flags & SAMPLE_OA_REPORT) == 0)
3798		privileged_op = false;
3799
3800	if (props->hold_preemption) {
3801		if (!props->single_context) {
3802			drm_dbg(&perf->i915->drm,
3803				"preemption disable with no context\n");
3804			ret = -EINVAL;
3805			goto err;
3806		}
3807		privileged_op = true;
3808	}
3809
3810	/*
3811	 * Asking for SSEU configuration is a priviliged operation.
3812	 */
3813	if (props->has_sseu)
3814		privileged_op = true;
3815	else
3816		get_default_sseu_config(&props->sseu, props->engine);
3817
3818	/* Similar to perf's kernel.perf_paranoid_cpu sysctl option
3819	 * we check a dev.i915.perf_stream_paranoid sysctl option
3820	 * to determine if it's ok to access system wide OA counters
3821	 * without CAP_PERFMON or CAP_SYS_ADMIN privileges.
3822	 */
3823	if (privileged_op &&
3824	    i915_perf_stream_paranoid && !perfmon_capable()) {
3825		drm_dbg(&perf->i915->drm,
3826			"Insufficient privileges to open i915 perf stream\n");
3827		ret = -EACCES;
3828		goto err_ctx;
3829	}
3830
3831	stream = kzalloc(sizeof(*stream), GFP_KERNEL);
3832	if (!stream) {
3833		ret = -ENOMEM;
3834		goto err_ctx;
3835	}
3836
3837	stream->perf = perf;
3838	stream->ctx = specific_ctx;
3839	stream->poll_oa_period = props->poll_oa_period;
3840
3841	ret = i915_oa_stream_init(stream, param, props);
3842	if (ret)
3843		goto err_alloc;
3844
3845	/* we avoid simply assigning stream->sample_flags = props->sample_flags
3846	 * to have _stream_init check the combination of sample flags more
3847	 * thoroughly, but still this is the expected result at this point.
3848	 */
3849	if (WARN_ON(stream->sample_flags != props->sample_flags)) {
3850		ret = -ENODEV;
3851		goto err_flags;
3852	}
3853
3854	if (param->flags & I915_PERF_FLAG_FD_CLOEXEC)
3855		f_flags |= O_CLOEXEC;
3856	if (param->flags & I915_PERF_FLAG_FD_NONBLOCK)
3857		f_flags |= O_NONBLOCK;
3858
3859	stream_fd = anon_inode_getfd("[i915_perf]", &fops, stream, f_flags);
3860	if (stream_fd < 0) {
3861		ret = stream_fd;
3862		goto err_flags;
3863	}
3864
3865	if (!(param->flags & I915_PERF_FLAG_DISABLED))
3866		i915_perf_enable_locked(stream);
3867
3868	/* Take a reference on the driver that will be kept with stream_fd
3869	 * until its release.
3870	 */
3871	drm_dev_get(&perf->i915->drm);
3872
3873	return stream_fd;
3874
3875err_flags:
3876	if (stream->ops->destroy)
3877		stream->ops->destroy(stream);
3878err_alloc:
3879	kfree(stream);
3880err_ctx:
3881	if (specific_ctx)
3882		i915_gem_context_put(specific_ctx);
3883err:
3884	return ret;
3885}
3886
3887static u64 oa_exponent_to_ns(struct i915_perf *perf, int exponent)
3888{
3889	u64 nom = (2ULL << exponent) * NSEC_PER_SEC;
3890	u32 den = i915_perf_oa_timestamp_frequency(perf->i915);
3891
3892	return div_u64(nom + den - 1, den);
3893}
3894
3895static __always_inline bool
3896oa_format_valid(struct i915_perf *perf, enum drm_i915_oa_format format)
3897{
3898	return test_bit(format, perf->format_mask);
3899}
3900
3901static __always_inline void
3902oa_format_add(struct i915_perf *perf, enum drm_i915_oa_format format)
3903{
3904	__set_bit(format, perf->format_mask);
3905}
3906
3907/**
3908 * read_properties_unlocked - validate + copy userspace stream open properties
3909 * @perf: i915 perf instance
3910 * @uprops: The array of u64 key value pairs given by userspace
3911 * @n_props: The number of key value pairs expected in @uprops
3912 * @props: The stream configuration built up while validating properties
3913 *
3914 * Note this function only validates properties in isolation it doesn't
3915 * validate that the combination of properties makes sense or that all
3916 * properties necessary for a particular kind of stream have been set.
3917 *
3918 * Note that there currently aren't any ordering requirements for properties so
3919 * we shouldn't validate or assume anything about ordering here. This doesn't
3920 * rule out defining new properties with ordering requirements in the future.
3921 */
3922static int read_properties_unlocked(struct i915_perf *perf,
3923				    u64 __user *uprops,
3924				    u32 n_props,
3925				    struct perf_open_properties *props)
3926{
3927	u64 __user *uprop = uprops;
3928	u32 i;
3929	int ret;
3930
3931	memset(props, 0, sizeof(struct perf_open_properties));
3932	props->poll_oa_period = DEFAULT_POLL_PERIOD_NS;
3933
3934	if (!n_props) {
3935		drm_dbg(&perf->i915->drm,
3936			"No i915 perf properties given\n");
3937		return -EINVAL;
3938	}
3939
3940	/* At the moment we only support using i915-perf on the RCS. */
3941	props->engine = intel_engine_lookup_user(perf->i915,
3942						 I915_ENGINE_CLASS_RENDER,
3943						 0);
3944	if (!props->engine) {
3945		drm_dbg(&perf->i915->drm,
3946			"No RENDER-capable engines\n");
3947		return -EINVAL;
3948	}
3949
3950	/* Considering that ID = 0 is reserved and assuming that we don't
3951	 * (currently) expect any configurations to ever specify duplicate
3952	 * values for a particular property ID then the last _PROP_MAX value is
3953	 * one greater than the maximum number of properties we expect to get
3954	 * from userspace.
3955	 */
3956	if (n_props >= DRM_I915_PERF_PROP_MAX) {
3957		drm_dbg(&perf->i915->drm,
3958			"More i915 perf properties specified than exist\n");
3959		return -EINVAL;
3960	}
3961
3962	for (i = 0; i < n_props; i++) {
3963		u64 oa_period, oa_freq_hz;
3964		u64 id, value;
3965
3966		ret = get_user(id, uprop);
3967		if (ret)
3968			return ret;
3969
3970		ret = get_user(value, uprop + 1);
3971		if (ret)
3972			return ret;
3973
3974		if (id == 0 || id >= DRM_I915_PERF_PROP_MAX) {
3975			drm_dbg(&perf->i915->drm,
3976				"Unknown i915 perf property ID\n");
3977			return -EINVAL;
3978		}
3979
3980		switch ((enum drm_i915_perf_property_id)id) {
3981		case DRM_I915_PERF_PROP_CTX_HANDLE:
3982			props->single_context = 1;
3983			props->ctx_handle = value;
3984			break;
3985		case DRM_I915_PERF_PROP_SAMPLE_OA:
3986			if (value)
3987				props->sample_flags |= SAMPLE_OA_REPORT;
3988			break;
3989		case DRM_I915_PERF_PROP_OA_METRICS_SET:
3990			if (value == 0) {
3991				drm_dbg(&perf->i915->drm,
3992					"Unknown OA metric set ID\n");
3993				return -EINVAL;
3994			}
3995			props->metrics_set = value;
3996			break;
3997		case DRM_I915_PERF_PROP_OA_FORMAT:
3998			if (value == 0 || value >= I915_OA_FORMAT_MAX) {
3999				drm_dbg(&perf->i915->drm,
4000					"Out-of-range OA report format %llu\n",
4001					  value);
4002				return -EINVAL;
4003			}
4004			if (!oa_format_valid(perf, value)) {
4005				drm_dbg(&perf->i915->drm,
4006					"Unsupported OA report format %llu\n",
4007					  value);
4008				return -EINVAL;
4009			}
4010			props->oa_format = value;
4011			break;
4012		case DRM_I915_PERF_PROP_OA_EXPONENT:
4013			if (value > OA_EXPONENT_MAX) {
4014				drm_dbg(&perf->i915->drm,
4015					"OA timer exponent too high (> %u)\n",
4016					 OA_EXPONENT_MAX);
4017				return -EINVAL;
4018			}
4019
4020			/* Theoretically we can program the OA unit to sample
4021			 * e.g. every 160ns for HSW, 167ns for BDW/SKL or 104ns
4022			 * for BXT. We don't allow such high sampling
4023			 * frequencies by default unless root.
4024			 */
4025
4026			BUILD_BUG_ON(sizeof(oa_period) != 8);
4027			oa_period = oa_exponent_to_ns(perf, value);
4028
4029			/* This check is primarily to ensure that oa_period <=
4030			 * UINT32_MAX (before passing to do_div which only
4031			 * accepts a u32 denominator), but we can also skip
4032			 * checking anything < 1Hz which implicitly can't be
4033			 * limited via an integer oa_max_sample_rate.
4034			 */
4035			if (oa_period <= NSEC_PER_SEC) {
4036				u64 tmp = NSEC_PER_SEC;
4037				do_div(tmp, oa_period);
4038				oa_freq_hz = tmp;
4039			} else
4040				oa_freq_hz = 0;
4041
4042			if (oa_freq_hz > i915_oa_max_sample_rate && !perfmon_capable()) {
4043				drm_dbg(&perf->i915->drm,
4044					"OA exponent would exceed the max sampling frequency (sysctl dev.i915.oa_max_sample_rate) %uHz without CAP_PERFMON or CAP_SYS_ADMIN privileges\n",
4045					  i915_oa_max_sample_rate);
4046				return -EACCES;
4047			}
4048
4049			props->oa_periodic = true;
4050			props->oa_period_exponent = value;
4051			break;
4052		case DRM_I915_PERF_PROP_HOLD_PREEMPTION:
4053			props->hold_preemption = !!value;
4054			break;
4055		case DRM_I915_PERF_PROP_GLOBAL_SSEU: {
4056			struct drm_i915_gem_context_param_sseu user_sseu;
4057
4058			if (GRAPHICS_VER_FULL(perf->i915) >= IP_VER(12, 50)) {
4059				drm_dbg(&perf->i915->drm,
4060					"SSEU config not supported on gfx %x\n",
4061					GRAPHICS_VER_FULL(perf->i915));
4062				return -ENODEV;
4063			}
4064
4065			if (copy_from_user(&user_sseu,
4066					   u64_to_user_ptr(value),
4067					   sizeof(user_sseu))) {
4068				drm_dbg(&perf->i915->drm,
4069					"Unable to copy global sseu parameter\n");
4070				return -EFAULT;
4071			}
4072
4073			ret = get_sseu_config(&props->sseu, props->engine, &user_sseu);
4074			if (ret) {
4075				drm_dbg(&perf->i915->drm,
4076					"Invalid SSEU configuration\n");
4077				return ret;
4078			}
4079			props->has_sseu = true;
4080			break;
4081		}
4082		case DRM_I915_PERF_PROP_POLL_OA_PERIOD:
4083			if (value < 100000 /* 100us */) {
4084				drm_dbg(&perf->i915->drm,
4085					"OA availability timer too small (%lluns < 100us)\n",
4086					  value);
4087				return -EINVAL;
4088			}
4089			props->poll_oa_period = value;
4090			break;
4091		case DRM_I915_PERF_PROP_MAX:
4092			MISSING_CASE(id);
4093			return -EINVAL;
4094		}
4095
4096		uprop += 2;
4097	}
4098
4099	return 0;
4100}
4101
4102/**
4103 * i915_perf_open_ioctl - DRM ioctl() for userspace to open a stream FD
4104 * @dev: drm device
4105 * @data: ioctl data copied from userspace (unvalidated)
4106 * @file: drm file
4107 *
4108 * Validates the stream open parameters given by userspace including flags
4109 * and an array of u64 key, value pair properties.
4110 *
4111 * Very little is assumed up front about the nature of the stream being
4112 * opened (for instance we don't assume it's for periodic OA unit metrics). An
4113 * i915-perf stream is expected to be a suitable interface for other forms of
4114 * buffered data written by the GPU besides periodic OA metrics.
4115 *
4116 * Note we copy the properties from userspace outside of the i915 perf
4117 * mutex to avoid an awkward lockdep with mmap_lock.
4118 *
4119 * Most of the implementation details are handled by
4120 * i915_perf_open_ioctl_locked() after taking the &gt->perf.lock
4121 * mutex for serializing with any non-file-operation driver hooks.
4122 *
4123 * Return: A newly opened i915 Perf stream file descriptor or negative
4124 * error code on failure.
4125 */
4126int i915_perf_open_ioctl(struct drm_device *dev, void *data,
4127			 struct drm_file *file)
4128{
4129	struct i915_perf *perf = &to_i915(dev)->perf;
4130	struct drm_i915_perf_open_param *param = data;
4131	struct intel_gt *gt;
4132	struct perf_open_properties props;
4133	u32 known_open_flags;
4134	int ret;
4135
4136	if (!perf->i915) {
4137		drm_dbg(&perf->i915->drm,
4138			"i915 perf interface not available for this system\n");
4139		return -ENOTSUPP;
4140	}
4141
4142	known_open_flags = I915_PERF_FLAG_FD_CLOEXEC |
4143			   I915_PERF_FLAG_FD_NONBLOCK |
4144			   I915_PERF_FLAG_DISABLED;
4145	if (param->flags & ~known_open_flags) {
4146		drm_dbg(&perf->i915->drm,
4147			"Unknown drm_i915_perf_open_param flag\n");
4148		return -EINVAL;
4149	}
4150
4151	ret = read_properties_unlocked(perf,
4152				       u64_to_user_ptr(param->properties_ptr),
4153				       param->num_properties,
4154				       &props);
4155	if (ret)
4156		return ret;
4157
4158	gt = props.engine->gt;
4159
4160	mutex_lock(&gt->perf.lock);
4161	ret = i915_perf_open_ioctl_locked(perf, param, &props, file);
4162	mutex_unlock(&gt->perf.lock);
4163
4164	return ret;
4165}
4166
4167/**
4168 * i915_perf_register - exposes i915-perf to userspace
4169 * @i915: i915 device instance
4170 *
4171 * In particular OA metric sets are advertised under a sysfs metrics/
4172 * directory allowing userspace to enumerate valid IDs that can be
4173 * used to open an i915-perf stream.
4174 */
4175void i915_perf_register(struct drm_i915_private *i915)
4176{
4177	struct i915_perf *perf = &i915->perf;
4178	struct intel_gt *gt = to_gt(i915);
4179
4180	if (!perf->i915)
4181		return;
4182
4183	/* To be sure we're synchronized with an attempted
4184	 * i915_perf_open_ioctl(); considering that we register after
4185	 * being exposed to userspace.
4186	 */
4187	mutex_lock(&gt->perf.lock);
4188
4189	perf->metrics_kobj =
4190		kobject_create_and_add("metrics",
4191				       &i915->drm.primary->kdev->kobj);
4192
4193	mutex_unlock(&gt->perf.lock);
4194}
4195
4196/**
4197 * i915_perf_unregister - hide i915-perf from userspace
4198 * @i915: i915 device instance
4199 *
4200 * i915-perf state cleanup is split up into an 'unregister' and
4201 * 'deinit' phase where the interface is first hidden from
4202 * userspace by i915_perf_unregister() before cleaning up
4203 * remaining state in i915_perf_fini().
4204 */
4205void i915_perf_unregister(struct drm_i915_private *i915)
4206{
4207	struct i915_perf *perf = &i915->perf;
4208
4209	if (!perf->metrics_kobj)
4210		return;
4211
4212	kobject_put(perf->metrics_kobj);
4213	perf->metrics_kobj = NULL;
4214}
4215
4216static bool gen8_is_valid_flex_addr(struct i915_perf *perf, u32 addr)
4217{
4218	static const i915_reg_t flex_eu_regs[] = {
4219		EU_PERF_CNTL0,
4220		EU_PERF_CNTL1,
4221		EU_PERF_CNTL2,
4222		EU_PERF_CNTL3,
4223		EU_PERF_CNTL4,
4224		EU_PERF_CNTL5,
4225		EU_PERF_CNTL6,
4226	};
4227	int i;
4228
4229	for (i = 0; i < ARRAY_SIZE(flex_eu_regs); i++) {
4230		if (i915_mmio_reg_offset(flex_eu_regs[i]) == addr)
4231			return true;
4232	}
4233	return false;
4234}
4235
4236static bool reg_in_range_table(u32 addr, const struct i915_range *table)
4237{
4238	while (table->start || table->end) {
4239		if (addr >= table->start && addr <= table->end)
4240			return true;
4241
4242		table++;
4243	}
4244
4245	return false;
4246}
4247
4248#define REG_EQUAL(addr, mmio) \
4249	((addr) == i915_mmio_reg_offset(mmio))
4250
4251static const struct i915_range gen7_oa_b_counters[] = {
4252	{ .start = 0x2710, .end = 0x272c },	/* OASTARTTRIG[1-8] */
4253	{ .start = 0x2740, .end = 0x275c },	/* OAREPORTTRIG[1-8] */
4254	{ .start = 0x2770, .end = 0x27ac },	/* OACEC[0-7][0-1] */
4255	{}
4256};
4257
4258static const struct i915_range gen12_oa_b_counters[] = {
4259	{ .start = 0x2b2c, .end = 0x2b2c },	/* GEN12_OAG_OA_PESS */
4260	{ .start = 0xd900, .end = 0xd91c },	/* GEN12_OAG_OASTARTTRIG[1-8] */
4261	{ .start = 0xd920, .end = 0xd93c },	/* GEN12_OAG_OAREPORTTRIG1[1-8] */
4262	{ .start = 0xd940, .end = 0xd97c },	/* GEN12_OAG_CEC[0-7][0-1] */
4263	{ .start = 0xdc00, .end = 0xdc3c },	/* GEN12_OAG_SCEC[0-7][0-1] */
4264	{ .start = 0xdc40, .end = 0xdc40 },	/* GEN12_OAG_SPCTR_CNF */
4265	{ .start = 0xdc44, .end = 0xdc44 },	/* GEN12_OAA_DBG_REG */
4266	{}
4267};
4268
4269static const struct i915_range xehp_oa_b_counters[] = {
4270	{ .start = 0xdc48, .end = 0xdc48 },	/* OAA_ENABLE_REG */
4271	{ .start = 0xdd00, .end = 0xdd48 },	/* OAG_LCE0_0 - OAA_LENABLE_REG */
4272};
4273
4274static const struct i915_range gen7_oa_mux_regs[] = {
4275	{ .start = 0x91b8, .end = 0x91cc },	/* OA_PERFCNT[1-2], OA_PERFMATRIX */
4276	{ .start = 0x9800, .end = 0x9888 },	/* MICRO_BP0_0 - NOA_WRITE */
4277	{ .start = 0xe180, .end = 0xe180 },	/* HALF_SLICE_CHICKEN2 */
4278	{}
4279};
4280
4281static const struct i915_range hsw_oa_mux_regs[] = {
4282	{ .start = 0x09e80, .end = 0x09ea4 }, /* HSW_MBVID2_NOA[0-9] */
4283	{ .start = 0x09ec0, .end = 0x09ec0 }, /* HSW_MBVID2_MISR0 */
4284	{ .start = 0x25100, .end = 0x2ff90 },
4285	{}
4286};
4287
4288static const struct i915_range chv_oa_mux_regs[] = {
4289	{ .start = 0x182300, .end = 0x1823a4 },
4290	{}
4291};
4292
4293static const struct i915_range gen8_oa_mux_regs[] = {
4294	{ .start = 0x0d00, .end = 0x0d2c },	/* RPM_CONFIG[0-1], NOA_CONFIG[0-8] */
4295	{ .start = 0x20cc, .end = 0x20cc },	/* WAIT_FOR_RC6_EXIT */
4296	{}
4297};
4298
4299static const struct i915_range gen11_oa_mux_regs[] = {
4300	{ .start = 0x91c8, .end = 0x91dc },	/* OA_PERFCNT[3-4] */
4301	{}
4302};
4303
4304static const struct i915_range gen12_oa_mux_regs[] = {
4305	{ .start = 0x0d00, .end = 0x0d04 },     /* RPM_CONFIG[0-1] */
4306	{ .start = 0x0d0c, .end = 0x0d2c },     /* NOA_CONFIG[0-8] */
4307	{ .start = 0x9840, .end = 0x9840 },	/* GDT_CHICKEN_BITS */
4308	{ .start = 0x9884, .end = 0x9888 },	/* NOA_WRITE */
4309	{ .start = 0x20cc, .end = 0x20cc },	/* WAIT_FOR_RC6_EXIT */
4310	{}
4311};
4312
4313static bool gen7_is_valid_b_counter_addr(struct i915_perf *perf, u32 addr)
4314{
4315	return reg_in_range_table(addr, gen7_oa_b_counters);
4316}
4317
4318static bool gen8_is_valid_mux_addr(struct i915_perf *perf, u32 addr)
4319{
4320	return reg_in_range_table(addr, gen7_oa_mux_regs) ||
4321		reg_in_range_table(addr, gen8_oa_mux_regs);
4322}
4323
4324static bool gen11_is_valid_mux_addr(struct i915_perf *perf, u32 addr)
4325{
4326	return reg_in_range_table(addr, gen7_oa_mux_regs) ||
4327		reg_in_range_table(addr, gen8_oa_mux_regs) ||
4328		reg_in_range_table(addr, gen11_oa_mux_regs);
4329}
4330
4331static bool hsw_is_valid_mux_addr(struct i915_perf *perf, u32 addr)
4332{
4333	return reg_in_range_table(addr, gen7_oa_mux_regs) ||
4334		reg_in_range_table(addr, hsw_oa_mux_regs);
4335}
4336
4337static bool chv_is_valid_mux_addr(struct i915_perf *perf, u32 addr)
4338{
4339	return reg_in_range_table(addr, gen7_oa_mux_regs) ||
4340		reg_in_range_table(addr, chv_oa_mux_regs);
4341}
4342
4343static bool gen12_is_valid_b_counter_addr(struct i915_perf *perf, u32 addr)
4344{
4345	return reg_in_range_table(addr, gen12_oa_b_counters);
4346}
4347
4348static bool xehp_is_valid_b_counter_addr(struct i915_perf *perf, u32 addr)
4349{
4350	return reg_in_range_table(addr, xehp_oa_b_counters) ||
4351		reg_in_range_table(addr, gen12_oa_b_counters);
4352}
4353
4354static bool gen12_is_valid_mux_addr(struct i915_perf *perf, u32 addr)
4355{
4356	return reg_in_range_table(addr, gen12_oa_mux_regs);
4357}
4358
4359static u32 mask_reg_value(u32 reg, u32 val)
4360{
4361	/* HALF_SLICE_CHICKEN2 is programmed with a the
4362	 * WaDisableSTUnitPowerOptimization workaround. Make sure the value
4363	 * programmed by userspace doesn't change this.
4364	 */
4365	if (REG_EQUAL(reg, HALF_SLICE_CHICKEN2))
4366		val = val & ~_MASKED_BIT_ENABLE(GEN8_ST_PO_DISABLE);
4367
4368	/* WAIT_FOR_RC6_EXIT has only one bit fullfilling the function
4369	 * indicated by its name and a bunch of selection fields used by OA
4370	 * configs.
4371	 */
4372	if (REG_EQUAL(reg, WAIT_FOR_RC6_EXIT))
4373		val = val & ~_MASKED_BIT_ENABLE(HSW_WAIT_FOR_RC6_EXIT_ENABLE);
4374
4375	return val;
4376}
4377
4378static struct i915_oa_reg *alloc_oa_regs(struct i915_perf *perf,
4379					 bool (*is_valid)(struct i915_perf *perf, u32 addr),
4380					 u32 __user *regs,
4381					 u32 n_regs)
4382{
4383	struct i915_oa_reg *oa_regs;
4384	int err;
4385	u32 i;
4386
4387	if (!n_regs)
4388		return NULL;
4389
4390	/* No is_valid function means we're not allowing any register to be programmed. */
4391	GEM_BUG_ON(!is_valid);
4392	if (!is_valid)
4393		return ERR_PTR(-EINVAL);
4394
4395	oa_regs = kmalloc_array(n_regs, sizeof(*oa_regs), GFP_KERNEL);
4396	if (!oa_regs)
4397		return ERR_PTR(-ENOMEM);
4398
4399	for (i = 0; i < n_regs; i++) {
4400		u32 addr, value;
4401
4402		err = get_user(addr, regs);
4403		if (err)
4404			goto addr_err;
4405
4406		if (!is_valid(perf, addr)) {
4407			drm_dbg(&perf->i915->drm,
4408				"Invalid oa_reg address: %X\n", addr);
4409			err = -EINVAL;
4410			goto addr_err;
4411		}
4412
4413		err = get_user(value, regs + 1);
4414		if (err)
4415			goto addr_err;
4416
4417		oa_regs[i].addr = _MMIO(addr);
4418		oa_regs[i].value = mask_reg_value(addr, value);
4419
4420		regs += 2;
4421	}
4422
4423	return oa_regs;
4424
4425addr_err:
4426	kfree(oa_regs);
4427	return ERR_PTR(err);
4428}
4429
4430static ssize_t show_dynamic_id(struct kobject *kobj,
4431			       struct kobj_attribute *attr,
4432			       char *buf)
4433{
4434	struct i915_oa_config *oa_config =
4435		container_of(attr, typeof(*oa_config), sysfs_metric_id);
4436
4437	return sprintf(buf, "%d\n", oa_config->id);
4438}
4439
4440static int create_dynamic_oa_sysfs_entry(struct i915_perf *perf,
4441					 struct i915_oa_config *oa_config)
4442{
4443	sysfs_attr_init(&oa_config->sysfs_metric_id.attr);
4444	oa_config->sysfs_metric_id.attr.name = "id";
4445	oa_config->sysfs_metric_id.attr.mode = S_IRUGO;
4446	oa_config->sysfs_metric_id.show = show_dynamic_id;
4447	oa_config->sysfs_metric_id.store = NULL;
4448
4449	oa_config->attrs[0] = &oa_config->sysfs_metric_id.attr;
4450	oa_config->attrs[1] = NULL;
4451
4452	oa_config->sysfs_metric.name = oa_config->uuid;
4453	oa_config->sysfs_metric.attrs = oa_config->attrs;
4454
4455	return sysfs_create_group(perf->metrics_kobj,
4456				  &oa_config->sysfs_metric);
4457}
4458
4459/**
4460 * i915_perf_add_config_ioctl - DRM ioctl() for userspace to add a new OA config
4461 * @dev: drm device
4462 * @data: ioctl data (pointer to struct drm_i915_perf_oa_config) copied from
4463 *        userspace (unvalidated)
4464 * @file: drm file
4465 *
4466 * Validates the submitted OA register to be saved into a new OA config that
4467 * can then be used for programming the OA unit and its NOA network.
4468 *
4469 * Returns: A new allocated config number to be used with the perf open ioctl
4470 * or a negative error code on failure.
4471 */
4472int i915_perf_add_config_ioctl(struct drm_device *dev, void *data,
4473			       struct drm_file *file)
4474{
4475	struct i915_perf *perf = &to_i915(dev)->perf;
4476	struct drm_i915_perf_oa_config *args = data;
4477	struct i915_oa_config *oa_config, *tmp;
4478	struct i915_oa_reg *regs;
4479	int err, id;
4480
4481	if (!perf->i915) {
4482		drm_dbg(&perf->i915->drm,
4483			"i915 perf interface not available for this system\n");
4484		return -ENOTSUPP;
4485	}
4486
4487	if (!perf->metrics_kobj) {
4488		drm_dbg(&perf->i915->drm,
4489			"OA metrics weren't advertised via sysfs\n");
4490		return -EINVAL;
4491	}
4492
4493	if (i915_perf_stream_paranoid && !perfmon_capable()) {
4494		drm_dbg(&perf->i915->drm,
4495			"Insufficient privileges to add i915 OA config\n");
4496		return -EACCES;
4497	}
4498
4499	if ((!args->mux_regs_ptr || !args->n_mux_regs) &&
4500	    (!args->boolean_regs_ptr || !args->n_boolean_regs) &&
4501	    (!args->flex_regs_ptr || !args->n_flex_regs)) {
4502		drm_dbg(&perf->i915->drm,
4503			"No OA registers given\n");
4504		return -EINVAL;
4505	}
4506
4507	oa_config = kzalloc(sizeof(*oa_config), GFP_KERNEL);
4508	if (!oa_config) {
4509		drm_dbg(&perf->i915->drm,
4510			"Failed to allocate memory for the OA config\n");
4511		return -ENOMEM;
4512	}
4513
4514	oa_config->perf = perf;
4515	kref_init(&oa_config->ref);
4516
4517	if (!uuid_is_valid(args->uuid)) {
4518		drm_dbg(&perf->i915->drm,
4519			"Invalid uuid format for OA config\n");
4520		err = -EINVAL;
4521		goto reg_err;
4522	}
4523
4524	/* Last character in oa_config->uuid will be 0 because oa_config is
4525	 * kzalloc.
4526	 */
4527	memcpy(oa_config->uuid, args->uuid, sizeof(args->uuid));
4528
4529	oa_config->mux_regs_len = args->n_mux_regs;
4530	regs = alloc_oa_regs(perf,
4531			     perf->ops.is_valid_mux_reg,
4532			     u64_to_user_ptr(args->mux_regs_ptr),
4533			     args->n_mux_regs);
4534
4535	if (IS_ERR(regs)) {
4536		drm_dbg(&perf->i915->drm,
4537			"Failed to create OA config for mux_regs\n");
4538		err = PTR_ERR(regs);
4539		goto reg_err;
4540	}
4541	oa_config->mux_regs = regs;
4542
4543	oa_config->b_counter_regs_len = args->n_boolean_regs;
4544	regs = alloc_oa_regs(perf,
4545			     perf->ops.is_valid_b_counter_reg,
4546			     u64_to_user_ptr(args->boolean_regs_ptr),
4547			     args->n_boolean_regs);
4548
4549	if (IS_ERR(regs)) {
4550		drm_dbg(&perf->i915->drm,
4551			"Failed to create OA config for b_counter_regs\n");
4552		err = PTR_ERR(regs);
4553		goto reg_err;
4554	}
4555	oa_config->b_counter_regs = regs;
4556
4557	if (GRAPHICS_VER(perf->i915) < 8) {
4558		if (args->n_flex_regs != 0) {
4559			err = -EINVAL;
4560			goto reg_err;
4561		}
4562	} else {
4563		oa_config->flex_regs_len = args->n_flex_regs;
4564		regs = alloc_oa_regs(perf,
4565				     perf->ops.is_valid_flex_reg,
4566				     u64_to_user_ptr(args->flex_regs_ptr),
4567				     args->n_flex_regs);
4568
4569		if (IS_ERR(regs)) {
4570			drm_dbg(&perf->i915->drm,
4571				"Failed to create OA config for flex_regs\n");
4572			err = PTR_ERR(regs);
4573			goto reg_err;
4574		}
4575		oa_config->flex_regs = regs;
4576	}
4577
4578	err = mutex_lock_interruptible(&perf->metrics_lock);
4579	if (err)
4580		goto reg_err;
4581
4582	/* We shouldn't have too many configs, so this iteration shouldn't be
4583	 * too costly.
4584	 */
4585	idr_for_each_entry(&perf->metrics_idr, tmp, id) {
4586		if (!strcmp(tmp->uuid, oa_config->uuid)) {
4587			drm_dbg(&perf->i915->drm,
4588				"OA config already exists with this uuid\n");
4589			err = -EADDRINUSE;
4590			goto sysfs_err;
4591		}
4592	}
4593
4594	err = create_dynamic_oa_sysfs_entry(perf, oa_config);
4595	if (err) {
4596		drm_dbg(&perf->i915->drm,
4597			"Failed to create sysfs entry for OA config\n");
4598		goto sysfs_err;
4599	}
4600
4601	/* Config id 0 is invalid, id 1 for kernel stored test config. */
4602	oa_config->id = idr_alloc(&perf->metrics_idr,
4603				  oa_config, 2,
4604				  0, GFP_KERNEL);
4605	if (oa_config->id < 0) {
4606		drm_dbg(&perf->i915->drm,
4607			"Failed to create sysfs entry for OA config\n");
4608		err = oa_config->id;
4609		goto sysfs_err;
4610	}
4611
4612	mutex_unlock(&perf->metrics_lock);
4613
4614	drm_dbg(&perf->i915->drm,
4615		"Added config %s id=%i\n", oa_config->uuid, oa_config->id);
4616
4617	return oa_config->id;
4618
4619sysfs_err:
4620	mutex_unlock(&perf->metrics_lock);
4621reg_err:
4622	i915_oa_config_put(oa_config);
4623	drm_dbg(&perf->i915->drm,
4624		"Failed to add new OA config\n");
4625	return err;
4626}
4627
4628/**
4629 * i915_perf_remove_config_ioctl - DRM ioctl() for userspace to remove an OA config
4630 * @dev: drm device
4631 * @data: ioctl data (pointer to u64 integer) copied from userspace
4632 * @file: drm file
4633 *
4634 * Configs can be removed while being used, the will stop appearing in sysfs
4635 * and their content will be freed when the stream using the config is closed.
4636 *
4637 * Returns: 0 on success or a negative error code on failure.
4638 */
4639int i915_perf_remove_config_ioctl(struct drm_device *dev, void *data,
4640				  struct drm_file *file)
4641{
4642	struct i915_perf *perf = &to_i915(dev)->perf;
4643	u64 *arg = data;
4644	struct i915_oa_config *oa_config;
4645	int ret;
4646
4647	if (!perf->i915) {
4648		drm_dbg(&perf->i915->drm,
4649			"i915 perf interface not available for this system\n");
4650		return -ENOTSUPP;
4651	}
4652
4653	if (i915_perf_stream_paranoid && !perfmon_capable()) {
4654		drm_dbg(&perf->i915->drm,
4655			"Insufficient privileges to remove i915 OA config\n");
4656		return -EACCES;
4657	}
4658
4659	ret = mutex_lock_interruptible(&perf->metrics_lock);
4660	if (ret)
4661		return ret;
4662
4663	oa_config = idr_find(&perf->metrics_idr, *arg);
4664	if (!oa_config) {
4665		drm_dbg(&perf->i915->drm,
4666			"Failed to remove unknown OA config\n");
4667		ret = -ENOENT;
4668		goto err_unlock;
4669	}
4670
4671	GEM_BUG_ON(*arg != oa_config->id);
4672
4673	sysfs_remove_group(perf->metrics_kobj, &oa_config->sysfs_metric);
4674
4675	idr_remove(&perf->metrics_idr, *arg);
4676
4677	mutex_unlock(&perf->metrics_lock);
4678
4679	drm_dbg(&perf->i915->drm,
4680		"Removed config %s id=%i\n", oa_config->uuid, oa_config->id);
4681
4682	i915_oa_config_put(oa_config);
4683
4684	return 0;
4685
4686err_unlock:
4687	mutex_unlock(&perf->metrics_lock);
4688	return ret;
4689}
4690
4691static struct ctl_table oa_table[] = {
4692	{
4693	 .procname = "perf_stream_paranoid",
4694	 .data = &i915_perf_stream_paranoid,
4695	 .maxlen = sizeof(i915_perf_stream_paranoid),
4696	 .mode = 0644,
4697	 .proc_handler = proc_dointvec_minmax,
4698	 .extra1 = SYSCTL_ZERO,
4699	 .extra2 = SYSCTL_ONE,
4700	 },
4701	{
4702	 .procname = "oa_max_sample_rate",
4703	 .data = &i915_oa_max_sample_rate,
4704	 .maxlen = sizeof(i915_oa_max_sample_rate),
4705	 .mode = 0644,
4706	 .proc_handler = proc_dointvec_minmax,
4707	 .extra1 = SYSCTL_ZERO,
4708	 .extra2 = &oa_sample_rate_hard_limit,
4709	 },
4710	{}
4711};
4712
4713static void oa_init_supported_formats(struct i915_perf *perf)
4714{
4715	struct drm_i915_private *i915 = perf->i915;
4716	enum intel_platform platform = INTEL_INFO(i915)->platform;
4717
4718	switch (platform) {
4719	case INTEL_HASWELL:
4720		oa_format_add(perf, I915_OA_FORMAT_A13);
4721		oa_format_add(perf, I915_OA_FORMAT_A13);
4722		oa_format_add(perf, I915_OA_FORMAT_A29);
4723		oa_format_add(perf, I915_OA_FORMAT_A13_B8_C8);
4724		oa_format_add(perf, I915_OA_FORMAT_B4_C8);
4725		oa_format_add(perf, I915_OA_FORMAT_A45_B8_C8);
4726		oa_format_add(perf, I915_OA_FORMAT_B4_C8_A16);
4727		oa_format_add(perf, I915_OA_FORMAT_C4_B8);
4728		break;
4729
4730	case INTEL_BROADWELL:
4731	case INTEL_CHERRYVIEW:
4732	case INTEL_SKYLAKE:
4733	case INTEL_BROXTON:
4734	case INTEL_KABYLAKE:
4735	case INTEL_GEMINILAKE:
4736	case INTEL_COFFEELAKE:
4737	case INTEL_COMETLAKE:
4738	case INTEL_ICELAKE:
4739	case INTEL_ELKHARTLAKE:
4740	case INTEL_JASPERLAKE:
4741	case INTEL_TIGERLAKE:
4742	case INTEL_ROCKETLAKE:
4743	case INTEL_DG1:
4744	case INTEL_ALDERLAKE_S:
4745	case INTEL_ALDERLAKE_P:
4746		oa_format_add(perf, I915_OA_FORMAT_A12);
4747		oa_format_add(perf, I915_OA_FORMAT_A12_B8_C8);
4748		oa_format_add(perf, I915_OA_FORMAT_A32u40_A4u32_B8_C8);
4749		oa_format_add(perf, I915_OA_FORMAT_C4_B8);
4750		break;
4751
4752	case INTEL_DG2:
4753		oa_format_add(perf, I915_OAR_FORMAT_A32u40_A4u32_B8_C8);
4754		oa_format_add(perf, I915_OA_FORMAT_A24u40_A14u32_B8_C8);
4755		break;
4756
4757	default:
4758		MISSING_CASE(platform);
4759	}
4760}
4761
4762static void i915_perf_init_info(struct drm_i915_private *i915)
4763{
4764	struct i915_perf *perf = &i915->perf;
4765
4766	switch (GRAPHICS_VER(i915)) {
4767	case 8:
4768		perf->ctx_oactxctrl_offset = 0x120;
4769		perf->ctx_flexeu0_offset = 0x2ce;
4770		perf->gen8_valid_ctx_bit = BIT(25);
4771		break;
4772	case 9:
4773		perf->ctx_oactxctrl_offset = 0x128;
4774		perf->ctx_flexeu0_offset = 0x3de;
4775		perf->gen8_valid_ctx_bit = BIT(16);
4776		break;
4777	case 11:
4778		perf->ctx_oactxctrl_offset = 0x124;
4779		perf->ctx_flexeu0_offset = 0x78e;
4780		perf->gen8_valid_ctx_bit = BIT(16);
4781		break;
4782	case 12:
4783		/*
4784		 * Calculate offset at runtime in oa_pin_context for gen12 and
4785		 * cache the value in perf->ctx_oactxctrl_offset.
4786		 */
4787		break;
4788	default:
4789		MISSING_CASE(GRAPHICS_VER(i915));
4790	}
4791}
4792
4793/**
4794 * i915_perf_init - initialize i915-perf state on module bind
4795 * @i915: i915 device instance
4796 *
4797 * Initializes i915-perf state without exposing anything to userspace.
4798 *
4799 * Note: i915-perf initialization is split into an 'init' and 'register'
4800 * phase with the i915_perf_register() exposing state to userspace.
4801 */
4802void i915_perf_init(struct drm_i915_private *i915)
4803{
4804	struct i915_perf *perf = &i915->perf;
4805
4806	perf->oa_formats = oa_formats;
4807	if (IS_HASWELL(i915)) {
4808		perf->ops.is_valid_b_counter_reg = gen7_is_valid_b_counter_addr;
4809		perf->ops.is_valid_mux_reg = hsw_is_valid_mux_addr;
4810		perf->ops.is_valid_flex_reg = NULL;
4811		perf->ops.enable_metric_set = hsw_enable_metric_set;
4812		perf->ops.disable_metric_set = hsw_disable_metric_set;
4813		perf->ops.oa_enable = gen7_oa_enable;
4814		perf->ops.oa_disable = gen7_oa_disable;
4815		perf->ops.read = gen7_oa_read;
4816		perf->ops.oa_hw_tail_read = gen7_oa_hw_tail_read;
4817	} else if (HAS_LOGICAL_RING_CONTEXTS(i915)) {
4818		/* Note: that although we could theoretically also support the
4819		 * legacy ringbuffer mode on BDW (and earlier iterations of
4820		 * this driver, before upstreaming did this) it didn't seem
4821		 * worth the complexity to maintain now that BDW+ enable
4822		 * execlist mode by default.
4823		 */
4824		perf->ops.read = gen8_oa_read;
4825		i915_perf_init_info(i915);
4826
4827		if (IS_GRAPHICS_VER(i915, 8, 9)) {
4828			perf->ops.is_valid_b_counter_reg =
4829				gen7_is_valid_b_counter_addr;
4830			perf->ops.is_valid_mux_reg =
4831				gen8_is_valid_mux_addr;
4832			perf->ops.is_valid_flex_reg =
4833				gen8_is_valid_flex_addr;
4834
4835			if (IS_CHERRYVIEW(i915)) {
4836				perf->ops.is_valid_mux_reg =
4837					chv_is_valid_mux_addr;
4838			}
4839
4840			perf->ops.oa_enable = gen8_oa_enable;
4841			perf->ops.oa_disable = gen8_oa_disable;
4842			perf->ops.enable_metric_set = gen8_enable_metric_set;
4843			perf->ops.disable_metric_set = gen8_disable_metric_set;
4844			perf->ops.oa_hw_tail_read = gen8_oa_hw_tail_read;
4845		} else if (GRAPHICS_VER(i915) == 11) {
4846			perf->ops.is_valid_b_counter_reg =
4847				gen7_is_valid_b_counter_addr;
4848			perf->ops.is_valid_mux_reg =
4849				gen11_is_valid_mux_addr;
4850			perf->ops.is_valid_flex_reg =
4851				gen8_is_valid_flex_addr;
4852
4853			perf->ops.oa_enable = gen8_oa_enable;
4854			perf->ops.oa_disable = gen8_oa_disable;
4855			perf->ops.enable_metric_set = gen8_enable_metric_set;
4856			perf->ops.disable_metric_set = gen11_disable_metric_set;
4857			perf->ops.oa_hw_tail_read = gen8_oa_hw_tail_read;
4858		} else if (GRAPHICS_VER(i915) == 12) {
4859			perf->ops.is_valid_b_counter_reg =
4860				HAS_OA_SLICE_CONTRIB_LIMITS(i915) ?
4861				xehp_is_valid_b_counter_addr :
4862				gen12_is_valid_b_counter_addr;
4863			perf->ops.is_valid_mux_reg =
4864				gen12_is_valid_mux_addr;
4865			perf->ops.is_valid_flex_reg =
4866				gen8_is_valid_flex_addr;
4867
4868			perf->ops.oa_enable = gen12_oa_enable;
4869			perf->ops.oa_disable = gen12_oa_disable;
4870			perf->ops.enable_metric_set = gen12_enable_metric_set;
4871			perf->ops.disable_metric_set = gen12_disable_metric_set;
4872			perf->ops.oa_hw_tail_read = gen12_oa_hw_tail_read;
4873		}
4874	}
4875
4876	if (perf->ops.enable_metric_set) {
4877		struct intel_gt *gt;
4878		int i;
4879
4880		for_each_gt(gt, i915, i)
4881			mutex_init(&gt->perf.lock);
4882
4883		/* Choose a representative limit */
4884		oa_sample_rate_hard_limit = to_gt(i915)->clock_frequency / 2;
4885
4886		mutex_init(&perf->metrics_lock);
4887		idr_init_base(&perf->metrics_idr, 1);
4888
4889		/* We set up some ratelimit state to potentially throttle any
4890		 * _NOTES about spurious, invalid OA reports which we don't
4891		 * forward to userspace.
4892		 *
4893		 * We print a _NOTE about any throttling when closing the
4894		 * stream instead of waiting until driver _fini which no one
4895		 * would ever see.
4896		 *
4897		 * Using the same limiting factors as printk_ratelimit()
4898		 */
4899		ratelimit_state_init(&perf->spurious_report_rs, 5 * HZ, 10);
4900		/* Since we use a DRM_NOTE for spurious reports it would be
4901		 * inconsistent to let __ratelimit() automatically print a
4902		 * warning for throttling.
4903		 */
4904		ratelimit_set_flags(&perf->spurious_report_rs,
4905				    RATELIMIT_MSG_ON_RELEASE);
4906
4907		ratelimit_state_init(&perf->tail_pointer_race,
4908				     5 * HZ, 10);
4909		ratelimit_set_flags(&perf->tail_pointer_race,
4910				    RATELIMIT_MSG_ON_RELEASE);
4911
4912		atomic64_set(&perf->noa_programming_delay,
4913			     500 * 1000 /* 500us */);
4914
4915		perf->i915 = i915;
4916
4917		oa_init_supported_formats(perf);
4918	}
4919}
4920
4921static int destroy_config(int id, void *p, void *data)
4922{
4923	i915_oa_config_put(p);
4924	return 0;
4925}
4926
4927int i915_perf_sysctl_register(void)
4928{
4929	sysctl_header = register_sysctl("dev/i915", oa_table);
4930	return 0;
4931}
4932
4933void i915_perf_sysctl_unregister(void)
4934{
4935	unregister_sysctl_table(sysctl_header);
4936}
4937
4938/**
4939 * i915_perf_fini - Counter part to i915_perf_init()
4940 * @i915: i915 device instance
4941 */
4942void i915_perf_fini(struct drm_i915_private *i915)
4943{
4944	struct i915_perf *perf = &i915->perf;
4945
4946	if (!perf->i915)
4947		return;
4948
4949	idr_for_each(&perf->metrics_idr, destroy_config, perf);
4950	idr_destroy(&perf->metrics_idr);
4951
4952	memset(&perf->ops, 0, sizeof(perf->ops));
4953	perf->i915 = NULL;
4954}
4955
4956/**
4957 * i915_perf_ioctl_version - Version of the i915-perf subsystem
4958 *
4959 * This version number is used by userspace to detect available features.
4960 */
4961int i915_perf_ioctl_version(void)
4962{
4963	/*
4964	 * 1: Initial version
4965	 *   I915_PERF_IOCTL_ENABLE
4966	 *   I915_PERF_IOCTL_DISABLE
4967	 *
4968	 * 2: Added runtime modification of OA config.
4969	 *   I915_PERF_IOCTL_CONFIG
4970	 *
4971	 * 3: Add DRM_I915_PERF_PROP_HOLD_PREEMPTION parameter to hold
4972	 *    preemption on a particular context so that performance data is
4973	 *    accessible from a delta of MI_RPC reports without looking at the
4974	 *    OA buffer.
4975	 *
4976	 * 4: Add DRM_I915_PERF_PROP_ALLOWED_SSEU to limit what contexts can
4977	 *    be run for the duration of the performance recording based on
4978	 *    their SSEU configuration.
4979	 *
4980	 * 5: Add DRM_I915_PERF_PROP_POLL_OA_PERIOD parameter that controls the
4981	 *    interval for the hrtimer used to check for OA data.
4982	 */
4983	return 5;
4984}
4985
4986#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
4987#include "selftests/i915_perf.c"
4988#endif