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