1 /*
2  * Copyright © 2013 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  *    Brad Volkin <bradley.d.volkin@intel.com>
25  *
26  */
27 
28 #include "gt/intel_engine.h"
29 #include "gt/intel_engine_regs.h"
30 #include "gt/intel_gpu_commands.h"
31 #include "gt/intel_gt_regs.h"
32 
33 #include "i915_cmd_parser.h"
34 #include "i915_drv.h"
35 #include "i915_memcpy.h"
36 #include "i915_reg.h"
37 
38 /**
39  * DOC: batch buffer command parser
40  *
41  * Motivation:
42  * Certain OpenGL features (e.g. transform feedback, performance monitoring)
43  * require userspace code to submit batches containing commands such as
44  * MI_LOAD_REGISTER_IMM to access various registers. Unfortunately, some
45  * generations of the hardware will noop these commands in "unsecure" batches
46  * (which includes all userspace batches submitted via i915) even though the
47  * commands may be safe and represent the intended programming model of the
48  * device.
49  *
50  * The software command parser is similar in operation to the command parsing
51  * done in hardware for unsecure batches. However, the software parser allows
52  * some operations that would be noop'd by hardware, if the parser determines
53  * the operation is safe, and submits the batch as "secure" to prevent hardware
54  * parsing.
55  *
56  * Threats:
57  * At a high level, the hardware (and software) checks attempt to prevent
58  * granting userspace undue privileges. There are three categories of privilege.
59  *
60  * First, commands which are explicitly defined as privileged or which should
61  * only be used by the kernel driver. The parser rejects such commands
62  *
63  * Second, commands which access registers. To support correct/enhanced
64  * userspace functionality, particularly certain OpenGL extensions, the parser
65  * provides a whitelist of registers which userspace may safely access
66  *
67  * Third, commands which access privileged memory (i.e. GGTT, HWS page, etc).
68  * The parser always rejects such commands.
69  *
70  * The majority of the problematic commands fall in the MI_* range, with only a
71  * few specific commands on each engine (e.g. PIPE_CONTROL and MI_FLUSH_DW).
72  *
73  * Implementation:
74  * Each engine maintains tables of commands and registers which the parser
75  * uses in scanning batch buffers submitted to that engine.
76  *
77  * Since the set of commands that the parser must check for is significantly
78  * smaller than the number of commands supported, the parser tables contain only
79  * those commands required by the parser. This generally works because command
80  * opcode ranges have standard command length encodings. So for commands that
81  * the parser does not need to check, it can easily skip them. This is
82  * implemented via a per-engine length decoding vfunc.
83  *
84  * Unfortunately, there are a number of commands that do not follow the standard
85  * length encoding for their opcode range, primarily amongst the MI_* commands.
86  * To handle this, the parser provides a way to define explicit "skip" entries
87  * in the per-engine command tables.
88  *
89  * Other command table entries map fairly directly to high level categories
90  * mentioned above: rejected, register whitelist. The parser implements a number
91  * of checks, including the privileged memory checks, via a general bitmasking
92  * mechanism.
93  */
94 
95 /*
96  * A command that requires special handling by the command parser.
97  */
98 struct drm_i915_cmd_descriptor {
99 	/*
100 	 * Flags describing how the command parser processes the command.
101 	 *
102 	 * CMD_DESC_FIXED: The command has a fixed length if this is set,
103 	 *                 a length mask if not set
104 	 * CMD_DESC_SKIP: The command is allowed but does not follow the
105 	 *                standard length encoding for the opcode range in
106 	 *                which it falls
107 	 * CMD_DESC_REJECT: The command is never allowed
108 	 * CMD_DESC_REGISTER: The command should be checked against the
109 	 *                    register whitelist for the appropriate ring
110 	 */
111 	u32 flags;
112 #define CMD_DESC_FIXED    (1<<0)
113 #define CMD_DESC_SKIP     (1<<1)
114 #define CMD_DESC_REJECT   (1<<2)
115 #define CMD_DESC_REGISTER (1<<3)
116 #define CMD_DESC_BITMASK  (1<<4)
117 
118 	/*
119 	 * The command's unique identification bits and the bitmask to get them.
120 	 * This isn't strictly the opcode field as defined in the spec and may
121 	 * also include type, subtype, and/or subop fields.
122 	 */
123 	struct {
124 		u32 value;
125 		u32 mask;
126 	} cmd;
127 
128 	/*
129 	 * The command's length. The command is either fixed length (i.e. does
130 	 * not include a length field) or has a length field mask. The flag
131 	 * CMD_DESC_FIXED indicates a fixed length. Otherwise, the command has
132 	 * a length mask. All command entries in a command table must include
133 	 * length information.
134 	 */
135 	union {
136 		u32 fixed;
137 		u32 mask;
138 	} length;
139 
140 	/*
141 	 * Describes where to find a register address in the command to check
142 	 * against the ring's register whitelist. Only valid if flags has the
143 	 * CMD_DESC_REGISTER bit set.
144 	 *
145 	 * A non-zero step value implies that the command may access multiple
146 	 * registers in sequence (e.g. LRI), in that case step gives the
147 	 * distance in dwords between individual offset fields.
148 	 */
149 	struct {
150 		u32 offset;
151 		u32 mask;
152 		u32 step;
153 	} reg;
154 
155 #define MAX_CMD_DESC_BITMASKS 3
156 	/*
157 	 * Describes command checks where a particular dword is masked and
158 	 * compared against an expected value. If the command does not match
159 	 * the expected value, the parser rejects it. Only valid if flags has
160 	 * the CMD_DESC_BITMASK bit set. Only entries where mask is non-zero
161 	 * are valid.
162 	 *
163 	 * If the check specifies a non-zero condition_mask then the parser
164 	 * only performs the check when the bits specified by condition_mask
165 	 * are non-zero.
166 	 */
167 	struct {
168 		u32 offset;
169 		u32 mask;
170 		u32 expected;
171 		u32 condition_offset;
172 		u32 condition_mask;
173 	} bits[MAX_CMD_DESC_BITMASKS];
174 };
175 
176 /*
177  * A table of commands requiring special handling by the command parser.
178  *
179  * Each engine has an array of tables. Each table consists of an array of
180  * command descriptors, which must be sorted with command opcodes in
181  * ascending order.
182  */
183 struct drm_i915_cmd_table {
184 	const struct drm_i915_cmd_descriptor *table;
185 	int count;
186 };
187 
188 #define STD_MI_OPCODE_SHIFT  (32 - 9)
189 #define STD_3D_OPCODE_SHIFT  (32 - 16)
190 #define STD_2D_OPCODE_SHIFT  (32 - 10)
191 #define STD_MFX_OPCODE_SHIFT (32 - 16)
192 #define MIN_OPCODE_SHIFT 16
193 
194 #define CMD(op, opm, f, lm, fl, ...)				\
195 	{							\
196 		.flags = (fl) | ((f) ? CMD_DESC_FIXED : 0),	\
197 		.cmd = { (op & ~0u << (opm)), ~0u << (opm) },	\
198 		.length = { (lm) },				\
199 		__VA_ARGS__					\
200 	}
201 
202 /* Convenience macros to compress the tables */
203 #define SMI STD_MI_OPCODE_SHIFT
204 #define S3D STD_3D_OPCODE_SHIFT
205 #define S2D STD_2D_OPCODE_SHIFT
206 #define SMFX STD_MFX_OPCODE_SHIFT
207 #define F true
208 #define S CMD_DESC_SKIP
209 #define R CMD_DESC_REJECT
210 #define W CMD_DESC_REGISTER
211 #define B CMD_DESC_BITMASK
212 
213 /*            Command                          Mask   Fixed Len   Action
214 	      ---------------------------------------------------------- */
215 static const struct drm_i915_cmd_descriptor gen7_common_cmds[] = {
216 	CMD(  MI_NOOP,                          SMI,    F,  1,      S  ),
217 	CMD(  MI_USER_INTERRUPT,                SMI,    F,  1,      R  ),
218 	CMD(  MI_WAIT_FOR_EVENT,                SMI,    F,  1,      R  ),
219 	CMD(  MI_ARB_CHECK,                     SMI,    F,  1,      S  ),
220 	CMD(  MI_REPORT_HEAD,                   SMI,    F,  1,      S  ),
221 	CMD(  MI_SUSPEND_FLUSH,                 SMI,    F,  1,      S  ),
222 	CMD(  MI_SEMAPHORE_MBOX,                SMI,   !F,  0xFF,   R  ),
223 	CMD(  MI_STORE_DWORD_INDEX,             SMI,   !F,  0xFF,   R  ),
224 	CMD(  MI_LOAD_REGISTER_IMM(1),          SMI,   !F,  0xFF,   W,
225 	      .reg = { .offset = 1, .mask = 0x007FFFFC, .step = 2 }    ),
226 	CMD(  MI_STORE_REGISTER_MEM,            SMI,    F,  3,     W | B,
227 	      .reg = { .offset = 1, .mask = 0x007FFFFC },
228 	      .bits = {{
229 			.offset = 0,
230 			.mask = MI_GLOBAL_GTT,
231 			.expected = 0,
232 	      }},						       ),
233 	CMD(  MI_LOAD_REGISTER_MEM,             SMI,    F,  3,     W | B,
234 	      .reg = { .offset = 1, .mask = 0x007FFFFC },
235 	      .bits = {{
236 			.offset = 0,
237 			.mask = MI_GLOBAL_GTT,
238 			.expected = 0,
239 	      }},						       ),
240 	/*
241 	 * MI_BATCH_BUFFER_START requires some special handling. It's not
242 	 * really a 'skip' action but it doesn't seem like it's worth adding
243 	 * a new action. See intel_engine_cmd_parser().
244 	 */
245 	CMD(  MI_BATCH_BUFFER_START,            SMI,   !F,  0xFF,   S  ),
246 };
247 
248 static const struct drm_i915_cmd_descriptor gen7_render_cmds[] = {
249 	CMD(  MI_FLUSH,                         SMI,    F,  1,      S  ),
250 	CMD(  MI_ARB_ON_OFF,                    SMI,    F,  1,      R  ),
251 	CMD(  MI_PREDICATE,                     SMI,    F,  1,      S  ),
252 	CMD(  MI_TOPOLOGY_FILTER,               SMI,    F,  1,      S  ),
253 	CMD(  MI_SET_APPID,                     SMI,    F,  1,      S  ),
254 	CMD(  MI_DISPLAY_FLIP,                  SMI,   !F,  0xFF,   R  ),
255 	CMD(  MI_SET_CONTEXT,                   SMI,   !F,  0xFF,   R  ),
256 	CMD(  MI_URB_CLEAR,                     SMI,   !F,  0xFF,   S  ),
257 	CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0x3F,   B,
258 	      .bits = {{
259 			.offset = 0,
260 			.mask = MI_GLOBAL_GTT,
261 			.expected = 0,
262 	      }},						       ),
263 	CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0xFF,   R  ),
264 	CMD(  MI_CLFLUSH,                       SMI,   !F,  0x3FF,  B,
265 	      .bits = {{
266 			.offset = 0,
267 			.mask = MI_GLOBAL_GTT,
268 			.expected = 0,
269 	      }},						       ),
270 	CMD(  MI_REPORT_PERF_COUNT,             SMI,   !F,  0x3F,   B,
271 	      .bits = {{
272 			.offset = 1,
273 			.mask = MI_REPORT_PERF_COUNT_GGTT,
274 			.expected = 0,
275 	      }},						       ),
276 	CMD(  MI_CONDITIONAL_BATCH_BUFFER_END,  SMI,   !F,  0xFF,   B,
277 	      .bits = {{
278 			.offset = 0,
279 			.mask = MI_GLOBAL_GTT,
280 			.expected = 0,
281 	      }},						       ),
282 	CMD(  GFX_OP_3DSTATE_VF_STATISTICS,     S3D,    F,  1,      S  ),
283 	CMD(  PIPELINE_SELECT,                  S3D,    F,  1,      S  ),
284 	CMD(  MEDIA_VFE_STATE,			S3D,   !F,  0xFFFF, B,
285 	      .bits = {{
286 			.offset = 2,
287 			.mask = MEDIA_VFE_STATE_MMIO_ACCESS_MASK,
288 			.expected = 0,
289 	      }},						       ),
290 	CMD(  GPGPU_OBJECT,                     S3D,   !F,  0xFF,   S  ),
291 	CMD(  GPGPU_WALKER,                     S3D,   !F,  0xFF,   S  ),
292 	CMD(  GFX_OP_3DSTATE_SO_DECL_LIST,      S3D,   !F,  0x1FF,  S  ),
293 	CMD(  GFX_OP_PIPE_CONTROL(5),           S3D,   !F,  0xFF,   B,
294 	      .bits = {{
295 			.offset = 1,
296 			.mask = (PIPE_CONTROL_MMIO_WRITE | PIPE_CONTROL_NOTIFY),
297 			.expected = 0,
298 	      },
299 	      {
300 			.offset = 1,
301 		        .mask = (PIPE_CONTROL_GLOBAL_GTT_IVB |
302 				 PIPE_CONTROL_STORE_DATA_INDEX),
303 			.expected = 0,
304 			.condition_offset = 1,
305 			.condition_mask = PIPE_CONTROL_POST_SYNC_OP_MASK,
306 	      }},						       ),
307 };
308 
309 static const struct drm_i915_cmd_descriptor hsw_render_cmds[] = {
310 	CMD(  MI_SET_PREDICATE,                 SMI,    F,  1,      S  ),
311 	CMD(  MI_RS_CONTROL,                    SMI,    F,  1,      S  ),
312 	CMD(  MI_URB_ATOMIC_ALLOC,              SMI,    F,  1,      S  ),
313 	CMD(  MI_SET_APPID,                     SMI,    F,  1,      S  ),
314 	CMD(  MI_RS_CONTEXT,                    SMI,    F,  1,      S  ),
315 	CMD(  MI_LOAD_SCAN_LINES_INCL,          SMI,   !F,  0x3F,   R  ),
316 	CMD(  MI_LOAD_SCAN_LINES_EXCL,          SMI,   !F,  0x3F,   R  ),
317 	CMD(  MI_LOAD_REGISTER_REG,             SMI,   !F,  0xFF,   W,
318 	      .reg = { .offset = 1, .mask = 0x007FFFFC, .step = 1 }    ),
319 	CMD(  MI_RS_STORE_DATA_IMM,             SMI,   !F,  0xFF,   S  ),
320 	CMD(  MI_LOAD_URB_MEM,                  SMI,   !F,  0xFF,   S  ),
321 	CMD(  MI_STORE_URB_MEM,                 SMI,   !F,  0xFF,   S  ),
322 	CMD(  GFX_OP_3DSTATE_DX9_CONSTANTF_VS,  S3D,   !F,  0x7FF,  S  ),
323 	CMD(  GFX_OP_3DSTATE_DX9_CONSTANTF_PS,  S3D,   !F,  0x7FF,  S  ),
324 
325 	CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_VS,  S3D,   !F,  0x1FF,  S  ),
326 	CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_GS,  S3D,   !F,  0x1FF,  S  ),
327 	CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_HS,  S3D,   !F,  0x1FF,  S  ),
328 	CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_DS,  S3D,   !F,  0x1FF,  S  ),
329 	CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_PS,  S3D,   !F,  0x1FF,  S  ),
330 };
331 
332 static const struct drm_i915_cmd_descriptor gen7_video_cmds[] = {
333 	CMD(  MI_ARB_ON_OFF,                    SMI,    F,  1,      R  ),
334 	CMD(  MI_SET_APPID,                     SMI,    F,  1,      S  ),
335 	CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0xFF,   B,
336 	      .bits = {{
337 			.offset = 0,
338 			.mask = MI_GLOBAL_GTT,
339 			.expected = 0,
340 	      }},						       ),
341 	CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0x3F,   R  ),
342 	CMD(  MI_FLUSH_DW,                      SMI,   !F,  0x3F,   B,
343 	      .bits = {{
344 			.offset = 0,
345 			.mask = MI_FLUSH_DW_NOTIFY,
346 			.expected = 0,
347 	      },
348 	      {
349 			.offset = 1,
350 			.mask = MI_FLUSH_DW_USE_GTT,
351 			.expected = 0,
352 			.condition_offset = 0,
353 			.condition_mask = MI_FLUSH_DW_OP_MASK,
354 	      },
355 	      {
356 			.offset = 0,
357 			.mask = MI_FLUSH_DW_STORE_INDEX,
358 			.expected = 0,
359 			.condition_offset = 0,
360 			.condition_mask = MI_FLUSH_DW_OP_MASK,
361 	      }},						       ),
362 	CMD(  MI_CONDITIONAL_BATCH_BUFFER_END,  SMI,   !F,  0xFF,   B,
363 	      .bits = {{
364 			.offset = 0,
365 			.mask = MI_GLOBAL_GTT,
366 			.expected = 0,
367 	      }},						       ),
368 	/*
369 	 * MFX_WAIT doesn't fit the way we handle length for most commands.
370 	 * It has a length field but it uses a non-standard length bias.
371 	 * It is always 1 dword though, so just treat it as fixed length.
372 	 */
373 	CMD(  MFX_WAIT,                         SMFX,   F,  1,      S  ),
374 };
375 
376 static const struct drm_i915_cmd_descriptor gen7_vecs_cmds[] = {
377 	CMD(  MI_ARB_ON_OFF,                    SMI,    F,  1,      R  ),
378 	CMD(  MI_SET_APPID,                     SMI,    F,  1,      S  ),
379 	CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0xFF,   B,
380 	      .bits = {{
381 			.offset = 0,
382 			.mask = MI_GLOBAL_GTT,
383 			.expected = 0,
384 	      }},						       ),
385 	CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0x3F,   R  ),
386 	CMD(  MI_FLUSH_DW,                      SMI,   !F,  0x3F,   B,
387 	      .bits = {{
388 			.offset = 0,
389 			.mask = MI_FLUSH_DW_NOTIFY,
390 			.expected = 0,
391 	      },
392 	      {
393 			.offset = 1,
394 			.mask = MI_FLUSH_DW_USE_GTT,
395 			.expected = 0,
396 			.condition_offset = 0,
397 			.condition_mask = MI_FLUSH_DW_OP_MASK,
398 	      },
399 	      {
400 			.offset = 0,
401 			.mask = MI_FLUSH_DW_STORE_INDEX,
402 			.expected = 0,
403 			.condition_offset = 0,
404 			.condition_mask = MI_FLUSH_DW_OP_MASK,
405 	      }},						       ),
406 	CMD(  MI_CONDITIONAL_BATCH_BUFFER_END,  SMI,   !F,  0xFF,   B,
407 	      .bits = {{
408 			.offset = 0,
409 			.mask = MI_GLOBAL_GTT,
410 			.expected = 0,
411 	      }},						       ),
412 };
413 
414 static const struct drm_i915_cmd_descriptor gen7_blt_cmds[] = {
415 	CMD(  MI_DISPLAY_FLIP,                  SMI,   !F,  0xFF,   R  ),
416 	CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0x3FF,  B,
417 	      .bits = {{
418 			.offset = 0,
419 			.mask = MI_GLOBAL_GTT,
420 			.expected = 0,
421 	      }},						       ),
422 	CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0x3F,   R  ),
423 	CMD(  MI_FLUSH_DW,                      SMI,   !F,  0x3F,   B,
424 	      .bits = {{
425 			.offset = 0,
426 			.mask = MI_FLUSH_DW_NOTIFY,
427 			.expected = 0,
428 	      },
429 	      {
430 			.offset = 1,
431 			.mask = MI_FLUSH_DW_USE_GTT,
432 			.expected = 0,
433 			.condition_offset = 0,
434 			.condition_mask = MI_FLUSH_DW_OP_MASK,
435 	      },
436 	      {
437 			.offset = 0,
438 			.mask = MI_FLUSH_DW_STORE_INDEX,
439 			.expected = 0,
440 			.condition_offset = 0,
441 			.condition_mask = MI_FLUSH_DW_OP_MASK,
442 	      }},						       ),
443 	CMD(  COLOR_BLT,                        S2D,   !F,  0x3F,   S  ),
444 	CMD(  SRC_COPY_BLT,                     S2D,   !F,  0x3F,   S  ),
445 };
446 
447 static const struct drm_i915_cmd_descriptor hsw_blt_cmds[] = {
448 	CMD(  MI_LOAD_SCAN_LINES_INCL,          SMI,   !F,  0x3F,   R  ),
449 	CMD(  MI_LOAD_SCAN_LINES_EXCL,          SMI,   !F,  0x3F,   R  ),
450 };
451 
452 /*
453  * For Gen9 we can still rely on the h/w to enforce cmd security, and only
454  * need to re-enforce the register access checks. We therefore only need to
455  * teach the cmdparser how to find the end of each command, and identify
456  * register accesses. The table doesn't need to reject any commands, and so
457  * the only commands listed here are:
458  *   1) Those that touch registers
459  *   2) Those that do not have the default 8-bit length
460  *
461  * Note that the default MI length mask chosen for this table is 0xFF, not
462  * the 0x3F used on older devices. This is because the vast majority of MI
463  * cmds on Gen9 use a standard 8-bit Length field.
464  * All the Gen9 blitter instructions are standard 0xFF length mask, and
465  * none allow access to non-general registers, so in fact no BLT cmds are
466  * included in the table at all.
467  *
468  */
469 static const struct drm_i915_cmd_descriptor gen9_blt_cmds[] = {
470 	CMD(  MI_NOOP,                          SMI,    F,  1,      S  ),
471 	CMD(  MI_USER_INTERRUPT,                SMI,    F,  1,      S  ),
472 	CMD(  MI_WAIT_FOR_EVENT,                SMI,    F,  1,      S  ),
473 	CMD(  MI_FLUSH,                         SMI,    F,  1,      S  ),
474 	CMD(  MI_ARB_CHECK,                     SMI,    F,  1,      S  ),
475 	CMD(  MI_REPORT_HEAD,                   SMI,    F,  1,      S  ),
476 	CMD(  MI_ARB_ON_OFF,                    SMI,    F,  1,      S  ),
477 	CMD(  MI_SUSPEND_FLUSH,                 SMI,    F,  1,      S  ),
478 	CMD(  MI_LOAD_SCAN_LINES_INCL,          SMI,   !F,  0x3F,   S  ),
479 	CMD(  MI_LOAD_SCAN_LINES_EXCL,          SMI,   !F,  0x3F,   S  ),
480 	CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0x3FF,  S  ),
481 	CMD(  MI_LOAD_REGISTER_IMM(1),          SMI,   !F,  0xFF,   W,
482 	      .reg = { .offset = 1, .mask = 0x007FFFFC, .step = 2 }    ),
483 	CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0x3FF,  S  ),
484 	CMD(  MI_STORE_REGISTER_MEM_GEN8,       SMI,    F,  4,      W,
485 	      .reg = { .offset = 1, .mask = 0x007FFFFC }               ),
486 	CMD(  MI_FLUSH_DW,                      SMI,   !F,  0x3F,   S  ),
487 	CMD(  MI_LOAD_REGISTER_MEM_GEN8,        SMI,    F,  4,      W,
488 	      .reg = { .offset = 1, .mask = 0x007FFFFC }               ),
489 	CMD(  MI_LOAD_REGISTER_REG,             SMI,    !F,  0xFF,  W,
490 	      .reg = { .offset = 1, .mask = 0x007FFFFC, .step = 1 }    ),
491 
492 	/*
493 	 * We allow BB_START but apply further checks. We just sanitize the
494 	 * basic fields here.
495 	 */
496 #define MI_BB_START_OPERAND_MASK   GENMASK(SMI-1, 0)
497 #define MI_BB_START_OPERAND_EXPECT (MI_BATCH_PPGTT_HSW | 1)
498 	CMD(  MI_BATCH_BUFFER_START_GEN8,       SMI,    !F,  0xFF,  B,
499 	      .bits = {{
500 			.offset = 0,
501 			.mask = MI_BB_START_OPERAND_MASK,
502 			.expected = MI_BB_START_OPERAND_EXPECT,
503 	      }},						       ),
504 };
505 
506 static const struct drm_i915_cmd_descriptor noop_desc =
507 	CMD(MI_NOOP, SMI, F, 1, S);
508 
509 #undef CMD
510 #undef SMI
511 #undef S3D
512 #undef S2D
513 #undef SMFX
514 #undef F
515 #undef S
516 #undef R
517 #undef W
518 #undef B
519 
520 static const struct drm_i915_cmd_table gen7_render_cmd_table[] = {
521 	{ gen7_common_cmds, ARRAY_SIZE(gen7_common_cmds) },
522 	{ gen7_render_cmds, ARRAY_SIZE(gen7_render_cmds) },
523 };
524 
525 static const struct drm_i915_cmd_table hsw_render_ring_cmd_table[] = {
526 	{ gen7_common_cmds, ARRAY_SIZE(gen7_common_cmds) },
527 	{ gen7_render_cmds, ARRAY_SIZE(gen7_render_cmds) },
528 	{ hsw_render_cmds, ARRAY_SIZE(hsw_render_cmds) },
529 };
530 
531 static const struct drm_i915_cmd_table gen7_video_cmd_table[] = {
532 	{ gen7_common_cmds, ARRAY_SIZE(gen7_common_cmds) },
533 	{ gen7_video_cmds, ARRAY_SIZE(gen7_video_cmds) },
534 };
535 
536 static const struct drm_i915_cmd_table hsw_vebox_cmd_table[] = {
537 	{ gen7_common_cmds, ARRAY_SIZE(gen7_common_cmds) },
538 	{ gen7_vecs_cmds, ARRAY_SIZE(gen7_vecs_cmds) },
539 };
540 
541 static const struct drm_i915_cmd_table gen7_blt_cmd_table[] = {
542 	{ gen7_common_cmds, ARRAY_SIZE(gen7_common_cmds) },
543 	{ gen7_blt_cmds, ARRAY_SIZE(gen7_blt_cmds) },
544 };
545 
546 static const struct drm_i915_cmd_table hsw_blt_ring_cmd_table[] = {
547 	{ gen7_common_cmds, ARRAY_SIZE(gen7_common_cmds) },
548 	{ gen7_blt_cmds, ARRAY_SIZE(gen7_blt_cmds) },
549 	{ hsw_blt_cmds, ARRAY_SIZE(hsw_blt_cmds) },
550 };
551 
552 static const struct drm_i915_cmd_table gen9_blt_cmd_table[] = {
553 	{ gen9_blt_cmds, ARRAY_SIZE(gen9_blt_cmds) },
554 };
555 
556 
557 /*
558  * Register whitelists, sorted by increasing register offset.
559  */
560 
561 /*
562  * An individual whitelist entry granting access to register addr.  If
563  * mask is non-zero the argument of immediate register writes will be
564  * AND-ed with mask, and the command will be rejected if the result
565  * doesn't match value.
566  *
567  * Registers with non-zero mask are only allowed to be written using
568  * LRI.
569  */
570 struct drm_i915_reg_descriptor {
571 	i915_reg_t addr;
572 	u32 mask;
573 	u32 value;
574 };
575 
576 /* Convenience macro for adding 32-bit registers. */
577 #define REG32(_reg, ...) \
578 	{ .addr = (_reg), __VA_ARGS__ }
579 
580 #define REG32_IDX(_reg, idx) \
581 	{ .addr = _reg(idx) }
582 
583 /*
584  * Convenience macro for adding 64-bit registers.
585  *
586  * Some registers that userspace accesses are 64 bits. The register
587  * access commands only allow 32-bit accesses. Hence, we have to include
588  * entries for both halves of the 64-bit registers.
589  */
590 #define REG64(_reg) \
591 	{ .addr = _reg }, \
592 	{ .addr = _reg ## _UDW }
593 
594 #define REG64_IDX(_reg, idx) \
595 	{ .addr = _reg(idx) }, \
596 	{ .addr = _reg ## _UDW(idx) }
597 
598 #define REG64_BASE_IDX(_reg, base, idx) \
599 	{ .addr = _reg(base, idx) }, \
600 	{ .addr = _reg ## _UDW(base, idx) }
601 
602 static const struct drm_i915_reg_descriptor gen7_render_regs[] = {
603 	REG64(GPGPU_THREADS_DISPATCHED),
604 	REG64(HS_INVOCATION_COUNT),
605 	REG64(DS_INVOCATION_COUNT),
606 	REG64(IA_VERTICES_COUNT),
607 	REG64(IA_PRIMITIVES_COUNT),
608 	REG64(VS_INVOCATION_COUNT),
609 	REG64(GS_INVOCATION_COUNT),
610 	REG64(GS_PRIMITIVES_COUNT),
611 	REG64(CL_INVOCATION_COUNT),
612 	REG64(CL_PRIMITIVES_COUNT),
613 	REG64(PS_INVOCATION_COUNT),
614 	REG64(PS_DEPTH_COUNT),
615 	REG64_IDX(RING_TIMESTAMP, RENDER_RING_BASE),
616 	REG64_IDX(MI_PREDICATE_SRC0, RENDER_RING_BASE),
617 	REG64_IDX(MI_PREDICATE_SRC1, RENDER_RING_BASE),
618 	REG32(GEN7_3DPRIM_END_OFFSET),
619 	REG32(GEN7_3DPRIM_START_VERTEX),
620 	REG32(GEN7_3DPRIM_VERTEX_COUNT),
621 	REG32(GEN7_3DPRIM_INSTANCE_COUNT),
622 	REG32(GEN7_3DPRIM_START_INSTANCE),
623 	REG32(GEN7_3DPRIM_BASE_VERTEX),
624 	REG32(GEN7_GPGPU_DISPATCHDIMX),
625 	REG32(GEN7_GPGPU_DISPATCHDIMY),
626 	REG32(GEN7_GPGPU_DISPATCHDIMZ),
627 	REG64_IDX(RING_TIMESTAMP, BSD_RING_BASE),
628 	REG64_IDX(GEN7_SO_NUM_PRIMS_WRITTEN, 0),
629 	REG64_IDX(GEN7_SO_NUM_PRIMS_WRITTEN, 1),
630 	REG64_IDX(GEN7_SO_NUM_PRIMS_WRITTEN, 2),
631 	REG64_IDX(GEN7_SO_NUM_PRIMS_WRITTEN, 3),
632 	REG64_IDX(GEN7_SO_PRIM_STORAGE_NEEDED, 0),
633 	REG64_IDX(GEN7_SO_PRIM_STORAGE_NEEDED, 1),
634 	REG64_IDX(GEN7_SO_PRIM_STORAGE_NEEDED, 2),
635 	REG64_IDX(GEN7_SO_PRIM_STORAGE_NEEDED, 3),
636 	REG32(GEN7_SO_WRITE_OFFSET(0)),
637 	REG32(GEN7_SO_WRITE_OFFSET(1)),
638 	REG32(GEN7_SO_WRITE_OFFSET(2)),
639 	REG32(GEN7_SO_WRITE_OFFSET(3)),
640 	REG32(GEN7_L3SQCREG1),
641 	REG32(GEN7_L3CNTLREG2),
642 	REG32(GEN7_L3CNTLREG3),
643 	REG64_IDX(RING_TIMESTAMP, BLT_RING_BASE),
644 };
645 
646 static const struct drm_i915_reg_descriptor hsw_render_regs[] = {
647 	REG64_BASE_IDX(GEN8_RING_CS_GPR, RENDER_RING_BASE, 0),
648 	REG64_BASE_IDX(GEN8_RING_CS_GPR, RENDER_RING_BASE, 1),
649 	REG64_BASE_IDX(GEN8_RING_CS_GPR, RENDER_RING_BASE, 2),
650 	REG64_BASE_IDX(GEN8_RING_CS_GPR, RENDER_RING_BASE, 3),
651 	REG64_BASE_IDX(GEN8_RING_CS_GPR, RENDER_RING_BASE, 4),
652 	REG64_BASE_IDX(GEN8_RING_CS_GPR, RENDER_RING_BASE, 5),
653 	REG64_BASE_IDX(GEN8_RING_CS_GPR, RENDER_RING_BASE, 6),
654 	REG64_BASE_IDX(GEN8_RING_CS_GPR, RENDER_RING_BASE, 7),
655 	REG64_BASE_IDX(GEN8_RING_CS_GPR, RENDER_RING_BASE, 8),
656 	REG64_BASE_IDX(GEN8_RING_CS_GPR, RENDER_RING_BASE, 9),
657 	REG64_BASE_IDX(GEN8_RING_CS_GPR, RENDER_RING_BASE, 10),
658 	REG64_BASE_IDX(GEN8_RING_CS_GPR, RENDER_RING_BASE, 11),
659 	REG64_BASE_IDX(GEN8_RING_CS_GPR, RENDER_RING_BASE, 12),
660 	REG64_BASE_IDX(GEN8_RING_CS_GPR, RENDER_RING_BASE, 13),
661 	REG64_BASE_IDX(GEN8_RING_CS_GPR, RENDER_RING_BASE, 14),
662 	REG64_BASE_IDX(GEN8_RING_CS_GPR, RENDER_RING_BASE, 15),
663 	REG32(HSW_SCRATCH1,
664 	      .mask = ~HSW_SCRATCH1_L3_DATA_ATOMICS_DISABLE,
665 	      .value = 0),
666 	REG32(HSW_ROW_CHICKEN3,
667 	      .mask = ~(HSW_ROW_CHICKEN3_L3_GLOBAL_ATOMICS_DISABLE << 16 |
668                         HSW_ROW_CHICKEN3_L3_GLOBAL_ATOMICS_DISABLE),
669 	      .value = 0),
670 };
671 
672 static const struct drm_i915_reg_descriptor gen7_blt_regs[] = {
673 	REG64_IDX(RING_TIMESTAMP, RENDER_RING_BASE),
674 	REG64_IDX(RING_TIMESTAMP, BSD_RING_BASE),
675 	REG32(BCS_SWCTRL),
676 	REG64_IDX(RING_TIMESTAMP, BLT_RING_BASE),
677 };
678 
679 static const struct drm_i915_reg_descriptor gen9_blt_regs[] = {
680 	REG64_IDX(RING_TIMESTAMP, RENDER_RING_BASE),
681 	REG64_IDX(RING_TIMESTAMP, BSD_RING_BASE),
682 	REG32(BCS_SWCTRL),
683 	REG64_IDX(RING_TIMESTAMP, BLT_RING_BASE),
684 	REG32_IDX(RING_CTX_TIMESTAMP, BLT_RING_BASE),
685 	REG64_BASE_IDX(GEN8_RING_CS_GPR, BLT_RING_BASE, 0),
686 	REG64_BASE_IDX(GEN8_RING_CS_GPR, BLT_RING_BASE, 1),
687 	REG64_BASE_IDX(GEN8_RING_CS_GPR, BLT_RING_BASE, 2),
688 	REG64_BASE_IDX(GEN8_RING_CS_GPR, BLT_RING_BASE, 3),
689 	REG64_BASE_IDX(GEN8_RING_CS_GPR, BLT_RING_BASE, 4),
690 	REG64_BASE_IDX(GEN8_RING_CS_GPR, BLT_RING_BASE, 5),
691 	REG64_BASE_IDX(GEN8_RING_CS_GPR, BLT_RING_BASE, 6),
692 	REG64_BASE_IDX(GEN8_RING_CS_GPR, BLT_RING_BASE, 7),
693 	REG64_BASE_IDX(GEN8_RING_CS_GPR, BLT_RING_BASE, 8),
694 	REG64_BASE_IDX(GEN8_RING_CS_GPR, BLT_RING_BASE, 9),
695 	REG64_BASE_IDX(GEN8_RING_CS_GPR, BLT_RING_BASE, 10),
696 	REG64_BASE_IDX(GEN8_RING_CS_GPR, BLT_RING_BASE, 11),
697 	REG64_BASE_IDX(GEN8_RING_CS_GPR, BLT_RING_BASE, 12),
698 	REG64_BASE_IDX(GEN8_RING_CS_GPR, BLT_RING_BASE, 13),
699 	REG64_BASE_IDX(GEN8_RING_CS_GPR, BLT_RING_BASE, 14),
700 	REG64_BASE_IDX(GEN8_RING_CS_GPR, BLT_RING_BASE, 15),
701 };
702 
703 #undef REG64
704 #undef REG32
705 
706 struct drm_i915_reg_table {
707 	const struct drm_i915_reg_descriptor *regs;
708 	int num_regs;
709 };
710 
711 static const struct drm_i915_reg_table ivb_render_reg_tables[] = {
712 	{ gen7_render_regs, ARRAY_SIZE(gen7_render_regs) },
713 };
714 
715 static const struct drm_i915_reg_table ivb_blt_reg_tables[] = {
716 	{ gen7_blt_regs, ARRAY_SIZE(gen7_blt_regs) },
717 };
718 
719 static const struct drm_i915_reg_table hsw_render_reg_tables[] = {
720 	{ gen7_render_regs, ARRAY_SIZE(gen7_render_regs) },
721 	{ hsw_render_regs, ARRAY_SIZE(hsw_render_regs) },
722 };
723 
724 static const struct drm_i915_reg_table hsw_blt_reg_tables[] = {
725 	{ gen7_blt_regs, ARRAY_SIZE(gen7_blt_regs) },
726 };
727 
728 static const struct drm_i915_reg_table gen9_blt_reg_tables[] = {
729 	{ gen9_blt_regs, ARRAY_SIZE(gen9_blt_regs) },
730 };
731 
732 static u32 gen7_render_get_cmd_length_mask(u32 cmd_header)
733 {
734 	u32 client = cmd_header >> INSTR_CLIENT_SHIFT;
735 	u32 subclient =
736 		(cmd_header & INSTR_SUBCLIENT_MASK) >> INSTR_SUBCLIENT_SHIFT;
737 
738 	if (client == INSTR_MI_CLIENT)
739 		return 0x3F;
740 	else if (client == INSTR_RC_CLIENT) {
741 		if (subclient == INSTR_MEDIA_SUBCLIENT)
742 			return 0xFFFF;
743 		else
744 			return 0xFF;
745 	}
746 
747 	DRM_DEBUG("CMD: Abnormal rcs cmd length! 0x%08X\n", cmd_header);
748 	return 0;
749 }
750 
751 static u32 gen7_bsd_get_cmd_length_mask(u32 cmd_header)
752 {
753 	u32 client = cmd_header >> INSTR_CLIENT_SHIFT;
754 	u32 subclient =
755 		(cmd_header & INSTR_SUBCLIENT_MASK) >> INSTR_SUBCLIENT_SHIFT;
756 	u32 op = (cmd_header & INSTR_26_TO_24_MASK) >> INSTR_26_TO_24_SHIFT;
757 
758 	if (client == INSTR_MI_CLIENT)
759 		return 0x3F;
760 	else if (client == INSTR_RC_CLIENT) {
761 		if (subclient == INSTR_MEDIA_SUBCLIENT) {
762 			if (op == 6)
763 				return 0xFFFF;
764 			else
765 				return 0xFFF;
766 		} else
767 			return 0xFF;
768 	}
769 
770 	DRM_DEBUG("CMD: Abnormal bsd cmd length! 0x%08X\n", cmd_header);
771 	return 0;
772 }
773 
774 static u32 gen7_blt_get_cmd_length_mask(u32 cmd_header)
775 {
776 	u32 client = cmd_header >> INSTR_CLIENT_SHIFT;
777 
778 	if (client == INSTR_MI_CLIENT)
779 		return 0x3F;
780 	else if (client == INSTR_BC_CLIENT)
781 		return 0xFF;
782 
783 	DRM_DEBUG("CMD: Abnormal blt cmd length! 0x%08X\n", cmd_header);
784 	return 0;
785 }
786 
787 static u32 gen9_blt_get_cmd_length_mask(u32 cmd_header)
788 {
789 	u32 client = cmd_header >> INSTR_CLIENT_SHIFT;
790 
791 	if (client == INSTR_MI_CLIENT || client == INSTR_BC_CLIENT)
792 		return 0xFF;
793 
794 	DRM_DEBUG("CMD: Abnormal blt cmd length! 0x%08X\n", cmd_header);
795 	return 0;
796 }
797 
798 static bool validate_cmds_sorted(const struct intel_engine_cs *engine,
799 				 const struct drm_i915_cmd_table *cmd_tables,
800 				 int cmd_table_count)
801 {
802 	int i;
803 	bool ret = true;
804 
805 	if (!cmd_tables || cmd_table_count == 0)
806 		return true;
807 
808 	for (i = 0; i < cmd_table_count; i++) {
809 		const struct drm_i915_cmd_table *table = &cmd_tables[i];
810 		u32 previous = 0;
811 		int j;
812 
813 		for (j = 0; j < table->count; j++) {
814 			const struct drm_i915_cmd_descriptor *desc =
815 				&table->table[j];
816 			u32 curr = desc->cmd.value & desc->cmd.mask;
817 
818 			if (curr < previous) {
819 				drm_err(&engine->i915->drm,
820 					"CMD: %s [%d] command table not sorted: "
821 					"table=%d entry=%d cmd=0x%08X prev=0x%08X\n",
822 					engine->name, engine->id,
823 					i, j, curr, previous);
824 				ret = false;
825 			}
826 
827 			previous = curr;
828 		}
829 	}
830 
831 	return ret;
832 }
833 
834 static bool check_sorted(const struct intel_engine_cs *engine,
835 			 const struct drm_i915_reg_descriptor *reg_table,
836 			 int reg_count)
837 {
838 	int i;
839 	u32 previous = 0;
840 	bool ret = true;
841 
842 	for (i = 0; i < reg_count; i++) {
843 		u32 curr = i915_mmio_reg_offset(reg_table[i].addr);
844 
845 		if (curr < previous) {
846 			drm_err(&engine->i915->drm,
847 				"CMD: %s [%d] register table not sorted: "
848 				"entry=%d reg=0x%08X prev=0x%08X\n",
849 				engine->name, engine->id,
850 				i, curr, previous);
851 			ret = false;
852 		}
853 
854 		previous = curr;
855 	}
856 
857 	return ret;
858 }
859 
860 static bool validate_regs_sorted(struct intel_engine_cs *engine)
861 {
862 	int i;
863 	const struct drm_i915_reg_table *table;
864 
865 	for (i = 0; i < engine->reg_table_count; i++) {
866 		table = &engine->reg_tables[i];
867 		if (!check_sorted(engine, table->regs, table->num_regs))
868 			return false;
869 	}
870 
871 	return true;
872 }
873 
874 struct cmd_node {
875 	const struct drm_i915_cmd_descriptor *desc;
876 	struct hlist_node node;
877 };
878 
879 /*
880  * Different command ranges have different numbers of bits for the opcode. For
881  * example, MI commands use bits 31:23 while 3D commands use bits 31:16. The
882  * problem is that, for example, MI commands use bits 22:16 for other fields
883  * such as GGTT vs PPGTT bits. If we include those bits in the mask then when
884  * we mask a command from a batch it could hash to the wrong bucket due to
885  * non-opcode bits being set. But if we don't include those bits, some 3D
886  * commands may hash to the same bucket due to not including opcode bits that
887  * make the command unique. For now, we will risk hashing to the same bucket.
888  */
889 static inline u32 cmd_header_key(u32 x)
890 {
891 	switch (x >> INSTR_CLIENT_SHIFT) {
892 	default:
893 	case INSTR_MI_CLIENT:
894 		return x >> STD_MI_OPCODE_SHIFT;
895 	case INSTR_RC_CLIENT:
896 		return x >> STD_3D_OPCODE_SHIFT;
897 	case INSTR_BC_CLIENT:
898 		return x >> STD_2D_OPCODE_SHIFT;
899 	}
900 }
901 
902 static int init_hash_table(struct intel_engine_cs *engine,
903 			   const struct drm_i915_cmd_table *cmd_tables,
904 			   int cmd_table_count)
905 {
906 	int i, j;
907 
908 	hash_init(engine->cmd_hash);
909 
910 	for (i = 0; i < cmd_table_count; i++) {
911 		const struct drm_i915_cmd_table *table = &cmd_tables[i];
912 
913 		for (j = 0; j < table->count; j++) {
914 			const struct drm_i915_cmd_descriptor *desc =
915 				&table->table[j];
916 			struct cmd_node *desc_node =
917 				kmalloc(sizeof(*desc_node), GFP_KERNEL);
918 
919 			if (!desc_node)
920 				return -ENOMEM;
921 
922 			desc_node->desc = desc;
923 			hash_add(engine->cmd_hash, &desc_node->node,
924 				 cmd_header_key(desc->cmd.value));
925 		}
926 	}
927 
928 	return 0;
929 }
930 
931 static void fini_hash_table(struct intel_engine_cs *engine)
932 {
933 	struct hlist_node *tmp;
934 	struct cmd_node *desc_node;
935 	int i;
936 
937 	hash_for_each_safe(engine->cmd_hash, i, tmp, desc_node, node) {
938 		hash_del(&desc_node->node);
939 		kfree(desc_node);
940 	}
941 }
942 
943 /**
944  * intel_engine_init_cmd_parser() - set cmd parser related fields for an engine
945  * @engine: the engine to initialize
946  *
947  * Optionally initializes fields related to batch buffer command parsing in the
948  * struct intel_engine_cs based on whether the platform requires software
949  * command parsing.
950  */
951 int intel_engine_init_cmd_parser(struct intel_engine_cs *engine)
952 {
953 	const struct drm_i915_cmd_table *cmd_tables;
954 	int cmd_table_count;
955 	int ret;
956 
957 	if (GRAPHICS_VER(engine->i915) != 7 && !(GRAPHICS_VER(engine->i915) == 9 &&
958 						 engine->class == COPY_ENGINE_CLASS))
959 		return 0;
960 
961 	switch (engine->class) {
962 	case RENDER_CLASS:
963 		if (IS_HASWELL(engine->i915)) {
964 			cmd_tables = hsw_render_ring_cmd_table;
965 			cmd_table_count =
966 				ARRAY_SIZE(hsw_render_ring_cmd_table);
967 		} else {
968 			cmd_tables = gen7_render_cmd_table;
969 			cmd_table_count = ARRAY_SIZE(gen7_render_cmd_table);
970 		}
971 
972 		if (IS_HASWELL(engine->i915)) {
973 			engine->reg_tables = hsw_render_reg_tables;
974 			engine->reg_table_count = ARRAY_SIZE(hsw_render_reg_tables);
975 		} else {
976 			engine->reg_tables = ivb_render_reg_tables;
977 			engine->reg_table_count = ARRAY_SIZE(ivb_render_reg_tables);
978 		}
979 		engine->get_cmd_length_mask = gen7_render_get_cmd_length_mask;
980 		break;
981 	case VIDEO_DECODE_CLASS:
982 		cmd_tables = gen7_video_cmd_table;
983 		cmd_table_count = ARRAY_SIZE(gen7_video_cmd_table);
984 		engine->get_cmd_length_mask = gen7_bsd_get_cmd_length_mask;
985 		break;
986 	case COPY_ENGINE_CLASS:
987 		engine->get_cmd_length_mask = gen7_blt_get_cmd_length_mask;
988 		if (GRAPHICS_VER(engine->i915) == 9) {
989 			cmd_tables = gen9_blt_cmd_table;
990 			cmd_table_count = ARRAY_SIZE(gen9_blt_cmd_table);
991 			engine->get_cmd_length_mask =
992 				gen9_blt_get_cmd_length_mask;
993 
994 			/* BCS Engine unsafe without parser */
995 			engine->flags |= I915_ENGINE_REQUIRES_CMD_PARSER;
996 		} else if (IS_HASWELL(engine->i915)) {
997 			cmd_tables = hsw_blt_ring_cmd_table;
998 			cmd_table_count = ARRAY_SIZE(hsw_blt_ring_cmd_table);
999 		} else {
1000 			cmd_tables = gen7_blt_cmd_table;
1001 			cmd_table_count = ARRAY_SIZE(gen7_blt_cmd_table);
1002 		}
1003 
1004 		if (GRAPHICS_VER(engine->i915) == 9) {
1005 			engine->reg_tables = gen9_blt_reg_tables;
1006 			engine->reg_table_count =
1007 				ARRAY_SIZE(gen9_blt_reg_tables);
1008 		} else if (IS_HASWELL(engine->i915)) {
1009 			engine->reg_tables = hsw_blt_reg_tables;
1010 			engine->reg_table_count = ARRAY_SIZE(hsw_blt_reg_tables);
1011 		} else {
1012 			engine->reg_tables = ivb_blt_reg_tables;
1013 			engine->reg_table_count = ARRAY_SIZE(ivb_blt_reg_tables);
1014 		}
1015 		break;
1016 	case VIDEO_ENHANCEMENT_CLASS:
1017 		cmd_tables = hsw_vebox_cmd_table;
1018 		cmd_table_count = ARRAY_SIZE(hsw_vebox_cmd_table);
1019 		/* VECS can use the same length_mask function as VCS */
1020 		engine->get_cmd_length_mask = gen7_bsd_get_cmd_length_mask;
1021 		break;
1022 	default:
1023 		MISSING_CASE(engine->class);
1024 		goto out;
1025 	}
1026 
1027 	if (!validate_cmds_sorted(engine, cmd_tables, cmd_table_count)) {
1028 		drm_err(&engine->i915->drm,
1029 			"%s: command descriptions are not sorted\n",
1030 			engine->name);
1031 		goto out;
1032 	}
1033 	if (!validate_regs_sorted(engine)) {
1034 		drm_err(&engine->i915->drm,
1035 			"%s: registers are not sorted\n", engine->name);
1036 		goto out;
1037 	}
1038 
1039 	ret = init_hash_table(engine, cmd_tables, cmd_table_count);
1040 	if (ret) {
1041 		drm_err(&engine->i915->drm,
1042 			"%s: initialised failed!\n", engine->name);
1043 		fini_hash_table(engine);
1044 		goto out;
1045 	}
1046 
1047 	engine->flags |= I915_ENGINE_USING_CMD_PARSER;
1048 
1049 out:
1050 	if (intel_engine_requires_cmd_parser(engine) &&
1051 	    !intel_engine_using_cmd_parser(engine))
1052 		return -EINVAL;
1053 
1054 	return 0;
1055 }
1056 
1057 /**
1058  * intel_engine_cleanup_cmd_parser() - clean up cmd parser related fields
1059  * @engine: the engine to clean up
1060  *
1061  * Releases any resources related to command parsing that may have been
1062  * initialized for the specified engine.
1063  */
1064 void intel_engine_cleanup_cmd_parser(struct intel_engine_cs *engine)
1065 {
1066 	if (!intel_engine_using_cmd_parser(engine))
1067 		return;
1068 
1069 	fini_hash_table(engine);
1070 }
1071 
1072 static const struct drm_i915_cmd_descriptor*
1073 find_cmd_in_table(struct intel_engine_cs *engine,
1074 		  u32 cmd_header)
1075 {
1076 	struct cmd_node *desc_node;
1077 
1078 	hash_for_each_possible(engine->cmd_hash, desc_node, node,
1079 			       cmd_header_key(cmd_header)) {
1080 		const struct drm_i915_cmd_descriptor *desc = desc_node->desc;
1081 		if (((cmd_header ^ desc->cmd.value) & desc->cmd.mask) == 0)
1082 			return desc;
1083 	}
1084 
1085 	return NULL;
1086 }
1087 
1088 /*
1089  * Returns a pointer to a descriptor for the command specified by cmd_header.
1090  *
1091  * The caller must supply space for a default descriptor via the default_desc
1092  * parameter. If no descriptor for the specified command exists in the engine's
1093  * command parser tables, this function fills in default_desc based on the
1094  * engine's default length encoding and returns default_desc.
1095  */
1096 static const struct drm_i915_cmd_descriptor*
1097 find_cmd(struct intel_engine_cs *engine,
1098 	 u32 cmd_header,
1099 	 const struct drm_i915_cmd_descriptor *desc,
1100 	 struct drm_i915_cmd_descriptor *default_desc)
1101 {
1102 	u32 mask;
1103 
1104 	if (((cmd_header ^ desc->cmd.value) & desc->cmd.mask) == 0)
1105 		return desc;
1106 
1107 	desc = find_cmd_in_table(engine, cmd_header);
1108 	if (desc)
1109 		return desc;
1110 
1111 	mask = engine->get_cmd_length_mask(cmd_header);
1112 	if (!mask)
1113 		return NULL;
1114 
1115 	default_desc->cmd.value = cmd_header;
1116 	default_desc->cmd.mask = ~0u << MIN_OPCODE_SHIFT;
1117 	default_desc->length.mask = mask;
1118 	default_desc->flags = CMD_DESC_SKIP;
1119 	return default_desc;
1120 }
1121 
1122 static const struct drm_i915_reg_descriptor *
1123 __find_reg(const struct drm_i915_reg_descriptor *table, int count, u32 addr)
1124 {
1125 	int start = 0, end = count;
1126 	while (start < end) {
1127 		int mid = start + (end - start) / 2;
1128 		int ret = addr - i915_mmio_reg_offset(table[mid].addr);
1129 		if (ret < 0)
1130 			end = mid;
1131 		else if (ret > 0)
1132 			start = mid + 1;
1133 		else
1134 			return &table[mid];
1135 	}
1136 	return NULL;
1137 }
1138 
1139 static const struct drm_i915_reg_descriptor *
1140 find_reg(const struct intel_engine_cs *engine, u32 addr)
1141 {
1142 	const struct drm_i915_reg_table *table = engine->reg_tables;
1143 	const struct drm_i915_reg_descriptor *reg = NULL;
1144 	int count = engine->reg_table_count;
1145 
1146 	for (; !reg && (count > 0); ++table, --count)
1147 		reg = __find_reg(table->regs, table->num_regs, addr);
1148 
1149 	return reg;
1150 }
1151 
1152 /* Returns a vmap'd pointer to dst_obj, which the caller must unmap */
1153 static u32 *copy_batch(struct drm_i915_gem_object *dst_obj,
1154 		       struct drm_i915_gem_object *src_obj,
1155 		       unsigned long offset, unsigned long length,
1156 		       bool *needs_clflush_after)
1157 {
1158 	unsigned int src_needs_clflush;
1159 	unsigned int dst_needs_clflush;
1160 	void *dst, *src;
1161 	int ret;
1162 
1163 	ret = i915_gem_object_prepare_write(dst_obj, &dst_needs_clflush);
1164 	if (ret)
1165 		return ERR_PTR(ret);
1166 
1167 	dst = i915_gem_object_pin_map(dst_obj, I915_MAP_WB);
1168 	i915_gem_object_finish_access(dst_obj);
1169 	if (IS_ERR(dst))
1170 		return dst;
1171 
1172 	ret = i915_gem_object_prepare_read(src_obj, &src_needs_clflush);
1173 	if (ret) {
1174 		i915_gem_object_unpin_map(dst_obj);
1175 		return ERR_PTR(ret);
1176 	}
1177 
1178 	src = ERR_PTR(-ENODEV);
1179 	if (src_needs_clflush && i915_has_memcpy_from_wc()) {
1180 		src = i915_gem_object_pin_map(src_obj, I915_MAP_WC);
1181 		if (!IS_ERR(src)) {
1182 			i915_unaligned_memcpy_from_wc(dst,
1183 						      src + offset,
1184 						      length);
1185 			i915_gem_object_unpin_map(src_obj);
1186 		}
1187 	}
1188 	if (IS_ERR(src)) {
1189 		unsigned long x, n, remain;
1190 		void *ptr;
1191 
1192 		/*
1193 		 * We can avoid clflushing partial cachelines before the write
1194 		 * if we only every write full cache-lines. Since we know that
1195 		 * both the source and destination are in multiples of
1196 		 * PAGE_SIZE, we can simply round up to the next cacheline.
1197 		 * We don't care about copying too much here as we only
1198 		 * validate up to the end of the batch.
1199 		 */
1200 		remain = length;
1201 		if (dst_needs_clflush & CLFLUSH_BEFORE)
1202 			remain = round_up(remain,
1203 					  boot_cpu_data.x86_clflush_size);
1204 
1205 		ptr = dst;
1206 		x = offset_in_page(offset);
1207 		for (n = offset >> PAGE_SHIFT; remain; n++) {
1208 			int len = min(remain, PAGE_SIZE - x);
1209 
1210 			src = kmap_atomic(i915_gem_object_get_page(src_obj, n));
1211 			if (src_needs_clflush)
1212 				drm_clflush_virt_range(src + x, len);
1213 			memcpy(ptr, src + x, len);
1214 			kunmap_atomic(src);
1215 
1216 			ptr += len;
1217 			remain -= len;
1218 			x = 0;
1219 		}
1220 	}
1221 
1222 	i915_gem_object_finish_access(src_obj);
1223 
1224 	memset32(dst + length, 0, (dst_obj->base.size - length) / sizeof(u32));
1225 
1226 	/* dst_obj is returned with vmap pinned */
1227 	*needs_clflush_after = dst_needs_clflush & CLFLUSH_AFTER;
1228 
1229 	return dst;
1230 }
1231 
1232 static inline bool cmd_desc_is(const struct drm_i915_cmd_descriptor * const desc,
1233 			       const u32 cmd)
1234 {
1235 	return desc->cmd.value == (cmd & desc->cmd.mask);
1236 }
1237 
1238 static bool check_cmd(const struct intel_engine_cs *engine,
1239 		      const struct drm_i915_cmd_descriptor *desc,
1240 		      const u32 *cmd, u32 length)
1241 {
1242 	if (desc->flags & CMD_DESC_SKIP)
1243 		return true;
1244 
1245 	if (desc->flags & CMD_DESC_REJECT) {
1246 		DRM_DEBUG("CMD: Rejected command: 0x%08X\n", *cmd);
1247 		return false;
1248 	}
1249 
1250 	if (desc->flags & CMD_DESC_REGISTER) {
1251 		/*
1252 		 * Get the distance between individual register offset
1253 		 * fields if the command can perform more than one
1254 		 * access at a time.
1255 		 */
1256 		const u32 step = desc->reg.step ? desc->reg.step : length;
1257 		u32 offset;
1258 
1259 		for (offset = desc->reg.offset; offset < length;
1260 		     offset += step) {
1261 			const u32 reg_addr = cmd[offset] & desc->reg.mask;
1262 			const struct drm_i915_reg_descriptor *reg =
1263 				find_reg(engine, reg_addr);
1264 
1265 			if (!reg) {
1266 				DRM_DEBUG("CMD: Rejected register 0x%08X in command: 0x%08X (%s)\n",
1267 					  reg_addr, *cmd, engine->name);
1268 				return false;
1269 			}
1270 
1271 			/*
1272 			 * Check the value written to the register against the
1273 			 * allowed mask/value pair given in the whitelist entry.
1274 			 */
1275 			if (reg->mask) {
1276 				if (cmd_desc_is(desc, MI_LOAD_REGISTER_MEM)) {
1277 					DRM_DEBUG("CMD: Rejected LRM to masked register 0x%08X\n",
1278 						  reg_addr);
1279 					return false;
1280 				}
1281 
1282 				if (cmd_desc_is(desc, MI_LOAD_REGISTER_REG)) {
1283 					DRM_DEBUG("CMD: Rejected LRR to masked register 0x%08X\n",
1284 						  reg_addr);
1285 					return false;
1286 				}
1287 
1288 				if (cmd_desc_is(desc, MI_LOAD_REGISTER_IMM(1)) &&
1289 				    (offset + 2 > length ||
1290 				     (cmd[offset + 1] & reg->mask) != reg->value)) {
1291 					DRM_DEBUG("CMD: Rejected LRI to masked register 0x%08X\n",
1292 						  reg_addr);
1293 					return false;
1294 				}
1295 			}
1296 		}
1297 	}
1298 
1299 	if (desc->flags & CMD_DESC_BITMASK) {
1300 		int i;
1301 
1302 		for (i = 0; i < MAX_CMD_DESC_BITMASKS; i++) {
1303 			u32 dword;
1304 
1305 			if (desc->bits[i].mask == 0)
1306 				break;
1307 
1308 			if (desc->bits[i].condition_mask != 0) {
1309 				u32 offset =
1310 					desc->bits[i].condition_offset;
1311 				u32 condition = cmd[offset] &
1312 					desc->bits[i].condition_mask;
1313 
1314 				if (condition == 0)
1315 					continue;
1316 			}
1317 
1318 			if (desc->bits[i].offset >= length) {
1319 				DRM_DEBUG("CMD: Rejected command 0x%08X, too short to check bitmask (%s)\n",
1320 					  *cmd, engine->name);
1321 				return false;
1322 			}
1323 
1324 			dword = cmd[desc->bits[i].offset] &
1325 				desc->bits[i].mask;
1326 
1327 			if (dword != desc->bits[i].expected) {
1328 				DRM_DEBUG("CMD: Rejected command 0x%08X for bitmask 0x%08X (exp=0x%08X act=0x%08X) (%s)\n",
1329 					  *cmd,
1330 					  desc->bits[i].mask,
1331 					  desc->bits[i].expected,
1332 					  dword, engine->name);
1333 				return false;
1334 			}
1335 		}
1336 	}
1337 
1338 	return true;
1339 }
1340 
1341 static int check_bbstart(u32 *cmd, u32 offset, u32 length,
1342 			 u32 batch_length,
1343 			 u64 batch_addr,
1344 			 u64 shadow_addr,
1345 			 const unsigned long *jump_whitelist)
1346 {
1347 	u64 jump_offset, jump_target;
1348 	u32 target_cmd_offset, target_cmd_index;
1349 
1350 	/* For igt compatibility on older platforms */
1351 	if (!jump_whitelist) {
1352 		DRM_DEBUG("CMD: Rejecting BB_START for ggtt based submission\n");
1353 		return -EACCES;
1354 	}
1355 
1356 	if (length != 3) {
1357 		DRM_DEBUG("CMD: Recursive BB_START with bad length(%u)\n",
1358 			  length);
1359 		return -EINVAL;
1360 	}
1361 
1362 	jump_target = *(u64 *)(cmd + 1);
1363 	jump_offset = jump_target - batch_addr;
1364 
1365 	/*
1366 	 * Any underflow of jump_target is guaranteed to be outside the range
1367 	 * of a u32, so >= test catches both too large and too small
1368 	 */
1369 	if (jump_offset >= batch_length) {
1370 		DRM_DEBUG("CMD: BB_START to 0x%llx jumps out of BB\n",
1371 			  jump_target);
1372 		return -EINVAL;
1373 	}
1374 
1375 	/*
1376 	 * This cannot overflow a u32 because we already checked jump_offset
1377 	 * is within the BB, and the batch_length is a u32
1378 	 */
1379 	target_cmd_offset = lower_32_bits(jump_offset);
1380 	target_cmd_index = target_cmd_offset / sizeof(u32);
1381 
1382 	*(u64 *)(cmd + 1) = shadow_addr + target_cmd_offset;
1383 
1384 	if (target_cmd_index == offset)
1385 		return 0;
1386 
1387 	if (IS_ERR(jump_whitelist))
1388 		return PTR_ERR(jump_whitelist);
1389 
1390 	if (!test_bit(target_cmd_index, jump_whitelist)) {
1391 		DRM_DEBUG("CMD: BB_START to 0x%llx not a previously executed cmd\n",
1392 			  jump_target);
1393 		return -EINVAL;
1394 	}
1395 
1396 	return 0;
1397 }
1398 
1399 static unsigned long *alloc_whitelist(u32 batch_length)
1400 {
1401 	unsigned long *jmp;
1402 
1403 	/*
1404 	 * We expect batch_length to be less than 256KiB for known users,
1405 	 * i.e. we need at most an 8KiB bitmap allocation which should be
1406 	 * reasonably cheap due to kmalloc caches.
1407 	 */
1408 
1409 	/* Prefer to report transient allocation failure rather than hit oom */
1410 	jmp = bitmap_zalloc(DIV_ROUND_UP(batch_length, sizeof(u32)),
1411 			    GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN);
1412 	if (!jmp)
1413 		return ERR_PTR(-ENOMEM);
1414 
1415 	return jmp;
1416 }
1417 
1418 #define LENGTH_BIAS 2
1419 
1420 /**
1421  * intel_engine_cmd_parser() - parse a batch buffer for privilege violations
1422  * @engine: the engine on which the batch is to execute
1423  * @batch: the batch buffer in question
1424  * @batch_offset: byte offset in the batch at which execution starts
1425  * @batch_length: length of the commands in batch_obj
1426  * @shadow: validated copy of the batch buffer in question
1427  * @trampoline: true if we need to trampoline into privileged execution
1428  *
1429  * Parses the specified batch buffer looking for privilege violations as
1430  * described in the overview.
1431  *
1432  * Return: non-zero if the parser finds violations or otherwise fails; -EACCES
1433  * if the batch appears legal but should use hardware parsing
1434  */
1435 
1436 int intel_engine_cmd_parser(struct intel_engine_cs *engine,
1437 			    struct i915_vma *batch,
1438 			    unsigned long batch_offset,
1439 			    unsigned long batch_length,
1440 			    struct i915_vma *shadow,
1441 			    bool trampoline)
1442 {
1443 	u32 *cmd, *batch_end, offset = 0;
1444 	struct drm_i915_cmd_descriptor default_desc = noop_desc;
1445 	const struct drm_i915_cmd_descriptor *desc = &default_desc;
1446 	bool needs_clflush_after = false;
1447 	unsigned long *jump_whitelist;
1448 	u64 batch_addr, shadow_addr;
1449 	int ret = 0;
1450 
1451 	GEM_BUG_ON(!IS_ALIGNED(batch_offset, sizeof(*cmd)));
1452 	GEM_BUG_ON(!IS_ALIGNED(batch_length, sizeof(*cmd)));
1453 	GEM_BUG_ON(range_overflows_t(u64, batch_offset, batch_length,
1454 				     batch->size));
1455 	GEM_BUG_ON(!batch_length);
1456 
1457 	cmd = copy_batch(shadow->obj, batch->obj,
1458 			 batch_offset, batch_length,
1459 			 &needs_clflush_after);
1460 	if (IS_ERR(cmd)) {
1461 		DRM_DEBUG("CMD: Failed to copy batch\n");
1462 		return PTR_ERR(cmd);
1463 	}
1464 
1465 	jump_whitelist = NULL;
1466 	if (!trampoline)
1467 		/* Defer failure until attempted use */
1468 		jump_whitelist = alloc_whitelist(batch_length);
1469 
1470 	shadow_addr = gen8_canonical_addr(shadow->node.start);
1471 	batch_addr = gen8_canonical_addr(batch->node.start + batch_offset);
1472 
1473 	/*
1474 	 * We use the batch length as size because the shadow object is as
1475 	 * large or larger and copy_batch() will write MI_NOPs to the extra
1476 	 * space. Parsing should be faster in some cases this way.
1477 	 */
1478 	batch_end = cmd + batch_length / sizeof(*batch_end);
1479 	do {
1480 		u32 length;
1481 
1482 		if (*cmd == MI_BATCH_BUFFER_END)
1483 			break;
1484 
1485 		desc = find_cmd(engine, *cmd, desc, &default_desc);
1486 		if (!desc) {
1487 			DRM_DEBUG("CMD: Unrecognized command: 0x%08X\n", *cmd);
1488 			ret = -EINVAL;
1489 			break;
1490 		}
1491 
1492 		if (desc->flags & CMD_DESC_FIXED)
1493 			length = desc->length.fixed;
1494 		else
1495 			length = (*cmd & desc->length.mask) + LENGTH_BIAS;
1496 
1497 		if ((batch_end - cmd) < length) {
1498 			DRM_DEBUG("CMD: Command length exceeds batch length: 0x%08X length=%u batchlen=%td\n",
1499 				  *cmd,
1500 				  length,
1501 				  batch_end - cmd);
1502 			ret = -EINVAL;
1503 			break;
1504 		}
1505 
1506 		if (!check_cmd(engine, desc, cmd, length)) {
1507 			ret = -EACCES;
1508 			break;
1509 		}
1510 
1511 		if (cmd_desc_is(desc, MI_BATCH_BUFFER_START)) {
1512 			ret = check_bbstart(cmd, offset, length, batch_length,
1513 					    batch_addr, shadow_addr,
1514 					    jump_whitelist);
1515 			break;
1516 		}
1517 
1518 		if (!IS_ERR_OR_NULL(jump_whitelist))
1519 			__set_bit(offset, jump_whitelist);
1520 
1521 		cmd += length;
1522 		offset += length;
1523 		if  (cmd >= batch_end) {
1524 			DRM_DEBUG("CMD: Got to the end of the buffer w/o a BBE cmd!\n");
1525 			ret = -EINVAL;
1526 			break;
1527 		}
1528 	} while (1);
1529 
1530 	if (trampoline) {
1531 		/*
1532 		 * With the trampoline, the shadow is executed twice.
1533 		 *
1534 		 *   1 - starting at offset 0, in privileged mode
1535 		 *   2 - starting at offset batch_len, as non-privileged
1536 		 *
1537 		 * Only if the batch is valid and safe to execute, do we
1538 		 * allow the first privileged execution to proceed. If not,
1539 		 * we terminate the first batch and use the second batchbuffer
1540 		 * entry to chain to the original unsafe non-privileged batch,
1541 		 * leaving it to the HW to validate.
1542 		 */
1543 		*batch_end = MI_BATCH_BUFFER_END;
1544 
1545 		if (ret) {
1546 			/* Batch unsafe to execute with privileges, cancel! */
1547 			cmd = page_mask_bits(shadow->obj->mm.mapping);
1548 			*cmd = MI_BATCH_BUFFER_END;
1549 
1550 			/* If batch is unsafe but valid, jump to the original */
1551 			if (ret == -EACCES) {
1552 				unsigned int flags;
1553 
1554 				flags = MI_BATCH_NON_SECURE_I965;
1555 				if (IS_HASWELL(engine->i915))
1556 					flags = MI_BATCH_NON_SECURE_HSW;
1557 
1558 				GEM_BUG_ON(!IS_GRAPHICS_VER(engine->i915, 6, 7));
1559 				__gen6_emit_bb_start(batch_end,
1560 						     batch_addr,
1561 						     flags);
1562 
1563 				ret = 0; /* allow execution */
1564 			}
1565 		}
1566 	}
1567 
1568 	i915_gem_object_flush_map(shadow->obj);
1569 
1570 	if (!IS_ERR_OR_NULL(jump_whitelist))
1571 		kfree(jump_whitelist);
1572 	i915_gem_object_unpin_map(shadow->obj);
1573 	return ret;
1574 }
1575 
1576 /**
1577  * i915_cmd_parser_get_version() - get the cmd parser version number
1578  * @dev_priv: i915 device private
1579  *
1580  * The cmd parser maintains a simple increasing integer version number suitable
1581  * for passing to userspace clients to determine what operations are permitted.
1582  *
1583  * Return: the current version number of the cmd parser
1584  */
1585 int i915_cmd_parser_get_version(struct drm_i915_private *dev_priv)
1586 {
1587 	struct intel_engine_cs *engine;
1588 	bool active = false;
1589 
1590 	/* If the command parser is not enabled, report 0 - unsupported */
1591 	for_each_uabi_engine(engine, dev_priv) {
1592 		if (intel_engine_using_cmd_parser(engine)) {
1593 			active = true;
1594 			break;
1595 		}
1596 	}
1597 	if (!active)
1598 		return 0;
1599 
1600 	/*
1601 	 * Command parser version history
1602 	 *
1603 	 * 1. Initial version. Checks batches and reports violations, but leaves
1604 	 *    hardware parsing enabled (so does not allow new use cases).
1605 	 * 2. Allow access to the MI_PREDICATE_SRC0 and
1606 	 *    MI_PREDICATE_SRC1 registers.
1607 	 * 3. Allow access to the GPGPU_THREADS_DISPATCHED register.
1608 	 * 4. L3 atomic chicken bits of HSW_SCRATCH1 and HSW_ROW_CHICKEN3.
1609 	 * 5. GPGPU dispatch compute indirect registers.
1610 	 * 6. TIMESTAMP register and Haswell CS GPR registers
1611 	 * 7. Allow MI_LOAD_REGISTER_REG between whitelisted registers.
1612 	 * 8. Don't report cmd_check() failures as EINVAL errors to userspace;
1613 	 *    rely on the HW to NOOP disallowed commands as it would without
1614 	 *    the parser enabled.
1615 	 * 9. Don't whitelist or handle oacontrol specially, as ownership
1616 	 *    for oacontrol state is moving to i915-perf.
1617 	 * 10. Support for Gen9 BCS Parsing
1618 	 */
1619 	return 10;
1620 }
1621