xref: /netbsd-src/sys/external/bsd/drm2/dist/drm/i915/i915_cmd_parser.c (revision ead3d1654e47f32e4d9913893e03636589c10b70)
1 /*	$NetBSD: i915_cmd_parser.c,v 1.28 2021/12/19 12:25:37 riastradh Exp $	*/
2 
3 /*
4  * Copyright © 2013 Intel Corporation
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the "Software"),
8  * to deal in the Software without restriction, including without limitation
9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10  * and/or sell copies of the Software, and to permit persons to whom the
11  * Software is furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice (including the next
14  * paragraph) shall be included in all copies or substantial portions of the
15  * Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
22  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
23  * IN THE SOFTWARE.
24  *
25  * Authors:
26  *    Brad Volkin <bradley.d.volkin@intel.com>
27  *
28  */
29 
30 #include <sys/cdefs.h>
31 __KERNEL_RCSID(0, "$NetBSD: i915_cmd_parser.c,v 1.28 2021/12/19 12:25:37 riastradh Exp $");
32 
33 #include <linux/bitmap.h>
34 
35 #include "gt/intel_engine.h"
36 
37 #include "i915_drv.h"
38 #include "i915_memcpy.h"
39 
40 /**
41  * DOC: batch buffer command parser
42  *
43  * Motivation:
44  * Certain OpenGL features (e.g. transform feedback, performance monitoring)
45  * require userspace code to submit batches containing commands such as
46  * MI_LOAD_REGISTER_IMM to access various registers. Unfortunately, some
47  * generations of the hardware will noop these commands in "unsecure" batches
48  * (which includes all userspace batches submitted via i915) even though the
49  * commands may be safe and represent the intended programming model of the
50  * device.
51  *
52  * The software command parser is similar in operation to the command parsing
53  * done in hardware for unsecure batches. However, the software parser allows
54  * some operations that would be noop'd by hardware, if the parser determines
55  * the operation is safe, and submits the batch as "secure" to prevent hardware
56  * parsing.
57  *
58  * Threats:
59  * At a high level, the hardware (and software) checks attempt to prevent
60  * granting userspace undue privileges. There are three categories of privilege.
61  *
62  * First, commands which are explicitly defined as privileged or which should
63  * only be used by the kernel driver. The parser rejects such commands
64  *
65  * Second, commands which access registers. To support correct/enhanced
66  * userspace functionality, particularly certain OpenGL extensions, the parser
67  * provides a whitelist of registers which userspace may safely access
68  *
69  * Third, commands which access privileged memory (i.e. GGTT, HWS page, etc).
70  * The parser always rejects such commands.
71  *
72  * The majority of the problematic commands fall in the MI_* range, with only a
73  * few specific commands on each engine (e.g. PIPE_CONTROL and MI_FLUSH_DW).
74  *
75  * Implementation:
76  * Each engine maintains tables of commands and registers which the parser
77  * uses in scanning batch buffers submitted to that engine.
78  *
79  * Since the set of commands that the parser must check for is significantly
80  * smaller than the number of commands supported, the parser tables contain only
81  * those commands required by the parser. This generally works because command
82  * opcode ranges have standard command length encodings. So for commands that
83  * the parser does not need to check, it can easily skip them. This is
84  * implemented via a per-engine length decoding vfunc.
85  *
86  * Unfortunately, there are a number of commands that do not follow the standard
87  * length encoding for their opcode range, primarily amongst the MI_* commands.
88  * To handle this, the parser provides a way to define explicit "skip" entries
89  * in the per-engine command tables.
90  *
91  * Other command table entries map fairly directly to high level categories
92  * mentioned above: rejected, register whitelist. The parser implements a number
93  * of checks, including the privileged memory checks, via a general bitmasking
94  * mechanism.
95  */
96 
97 /*
98  * A command that requires special handling by the command parser.
99  */
100 struct drm_i915_cmd_descriptor {
101 	/*
102 	 * Flags describing how the command parser processes the command.
103 	 *
104 	 * CMD_DESC_FIXED: The command has a fixed length if this is set,
105 	 *                 a length mask if not set
106 	 * CMD_DESC_SKIP: The command is allowed but does not follow the
107 	 *                standard length encoding for the opcode range in
108 	 *                which it falls
109 	 * CMD_DESC_REJECT: The command is never allowed
110 	 * CMD_DESC_REGISTER: The command should be checked against the
111 	 *                    register whitelist for the appropriate ring
112 	 */
113 	u32 flags;
114 #define CMD_DESC_FIXED    (1<<0)
115 #define CMD_DESC_SKIP     (1<<1)
116 #define CMD_DESC_REJECT   (1<<2)
117 #define CMD_DESC_REGISTER (1<<3)
118 #define CMD_DESC_BITMASK  (1<<4)
119 
120 	/*
121 	 * The command's unique identification bits and the bitmask to get them.
122 	 * This isn't strictly the opcode field as defined in the spec and may
123 	 * also include type, subtype, and/or subop fields.
124 	 */
125 	struct {
126 		u32 value;
127 		u32 mask;
128 	} cmd;
129 
130 	/*
131 	 * The command's length. The command is either fixed length (i.e. does
132 	 * not include a length field) or has a length field mask. The flag
133 	 * CMD_DESC_FIXED indicates a fixed length. Otherwise, the command has
134 	 * a length mask. All command entries in a command table must include
135 	 * length information.
136 	 */
137 	union {
138 		u32 fixed;
139 		u32 mask;
140 	} length;
141 
142 	/*
143 	 * Describes where to find a register address in the command to check
144 	 * against the ring's register whitelist. Only valid if flags has the
145 	 * CMD_DESC_REGISTER bit set.
146 	 *
147 	 * A non-zero step value implies that the command may access multiple
148 	 * registers in sequence (e.g. LRI), in that case step gives the
149 	 * distance in dwords between individual offset fields.
150 	 */
151 	struct {
152 		u32 offset;
153 		u32 mask;
154 		u32 step;
155 	} reg;
156 
157 #define MAX_CMD_DESC_BITMASKS 3
158 	/*
159 	 * Describes command checks where a particular dword is masked and
160 	 * compared against an expected value. If the command does not match
161 	 * the expected value, the parser rejects it. Only valid if flags has
162 	 * the CMD_DESC_BITMASK bit set. Only entries where mask is non-zero
163 	 * are valid.
164 	 *
165 	 * If the check specifies a non-zero condition_mask then the parser
166 	 * only performs the check when the bits specified by condition_mask
167 	 * are non-zero.
168 	 */
169 	struct {
170 		u32 offset;
171 		u32 mask;
172 		u32 expected;
173 		u32 condition_offset;
174 		u32 condition_mask;
175 	} bits[MAX_CMD_DESC_BITMASKS];
176 };
177 
178 /*
179  * A table of commands requiring special handling by the command parser.
180  *
181  * Each engine has an array of tables. Each table consists of an array of
182  * command descriptors, which must be sorted with command opcodes in
183  * ascending order.
184  */
185 struct drm_i915_cmd_table {
186 	const struct drm_i915_cmd_descriptor *table;
187 	int count;
188 };
189 
190 #define STD_MI_OPCODE_SHIFT  (32 - 9)
191 #define STD_3D_OPCODE_SHIFT  (32 - 16)
192 #define STD_2D_OPCODE_SHIFT  (32 - 10)
193 #define STD_MFX_OPCODE_SHIFT (32 - 16)
194 #define MIN_OPCODE_SHIFT 16
195 
196 #define CMD(op, opm, f, lm, fl, ...)				\
197 	{							\
198 		.flags = (fl) | ((f) ? CMD_DESC_FIXED : 0),	\
199 		.cmd = { (op & ~0u << (opm)), ~0u << (opm) },	\
200 		.length = { (lm) },				\
201 		__VA_ARGS__					\
202 	}
203 
204 /* Convenience macros to compress the tables */
205 #define SMI STD_MI_OPCODE_SHIFT
206 #define S3D STD_3D_OPCODE_SHIFT
207 #define S2D STD_2D_OPCODE_SHIFT
208 #define SMFX STD_MFX_OPCODE_SHIFT
209 #define F true
210 #define S CMD_DESC_SKIP
211 #define R CMD_DESC_REJECT
212 #define W CMD_DESC_REGISTER
213 #define B CMD_DESC_BITMASK
214 
215 /*            Command                          Mask   Fixed Len   Action
216 	      ---------------------------------------------------------- */
217 static const struct drm_i915_cmd_descriptor gen7_common_cmds[] = {
218 	CMD(  MI_NOOP,                          SMI,    F,  1,      S  ),
219 	CMD(  MI_USER_INTERRUPT,                SMI,    F,  1,      R  ),
220 	CMD(  MI_WAIT_FOR_EVENT,                SMI,    F,  1,      R  ),
221 	CMD(  MI_ARB_CHECK,                     SMI,    F,  1,      S  ),
222 	CMD(  MI_REPORT_HEAD,                   SMI,    F,  1,      S  ),
223 	CMD(  MI_SUSPEND_FLUSH,                 SMI,    F,  1,      S  ),
224 	CMD(  MI_SEMAPHORE_MBOX,                SMI,   !F,  0xFF,   R  ),
225 	CMD(  MI_STORE_DWORD_INDEX,             SMI,   !F,  0xFF,   R  ),
226 	CMD(  MI_LOAD_REGISTER_IMM(1),          SMI,   !F,  0xFF,   W,
227 	      .reg = { .offset = 1, .mask = 0x007FFFFC, .step = 2 }    ),
228 	CMD(  MI_STORE_REGISTER_MEM,            SMI,    F,  3,     W | B,
229 	      .reg = { .offset = 1, .mask = 0x007FFFFC },
230 	      .bits = {{
231 			.offset = 0,
232 			.mask = MI_GLOBAL_GTT,
233 			.expected = 0,
234 	      }},						       ),
235 	CMD(  MI_LOAD_REGISTER_MEM,             SMI,    F,  3,     W | B,
236 	      .reg = { .offset = 1, .mask = 0x007FFFFC },
237 	      .bits = {{
238 			.offset = 0,
239 			.mask = MI_GLOBAL_GTT,
240 			.expected = 0,
241 	      }},						       ),
242 	/*
243 	 * MI_BATCH_BUFFER_START requires some special handling. It's not
244 	 * really a 'skip' action but it doesn't seem like it's worth adding
245 	 * a new action. See intel_engine_cmd_parser().
246 	 */
247 	CMD(  MI_BATCH_BUFFER_START,            SMI,   !F,  0xFF,   S  ),
248 };
249 
250 static const struct drm_i915_cmd_descriptor gen7_render_cmds[] = {
251 	CMD(  MI_FLUSH,                         SMI,    F,  1,      S  ),
252 	CMD(  MI_ARB_ON_OFF,                    SMI,    F,  1,      R  ),
253 	CMD(  MI_PREDICATE,                     SMI,    F,  1,      S  ),
254 	CMD(  MI_TOPOLOGY_FILTER,               SMI,    F,  1,      S  ),
255 	CMD(  MI_SET_APPID,                     SMI,    F,  1,      S  ),
256 	CMD(  MI_DISPLAY_FLIP,                  SMI,   !F,  0xFF,   R  ),
257 	CMD(  MI_SET_CONTEXT,                   SMI,   !F,  0xFF,   R  ),
258 	CMD(  MI_URB_CLEAR,                     SMI,   !F,  0xFF,   S  ),
259 	CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0x3F,   B,
260 	      .bits = {{
261 			.offset = 0,
262 			.mask = MI_GLOBAL_GTT,
263 			.expected = 0,
264 	      }},						       ),
265 	CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0xFF,   R  ),
266 	CMD(  MI_CLFLUSH,                       SMI,   !F,  0x3FF,  B,
267 	      .bits = {{
268 			.offset = 0,
269 			.mask = MI_GLOBAL_GTT,
270 			.expected = 0,
271 	      }},						       ),
272 	CMD(  MI_REPORT_PERF_COUNT,             SMI,   !F,  0x3F,   B,
273 	      .bits = {{
274 			.offset = 1,
275 			.mask = MI_REPORT_PERF_COUNT_GGTT,
276 			.expected = 0,
277 	      }},						       ),
278 	CMD(  MI_CONDITIONAL_BATCH_BUFFER_END,  SMI,   !F,  0xFF,   B,
279 	      .bits = {{
280 			.offset = 0,
281 			.mask = MI_GLOBAL_GTT,
282 			.expected = 0,
283 	      }},						       ),
284 	CMD(  GFX_OP_3DSTATE_VF_STATISTICS,     S3D,    F,  1,      S  ),
285 	CMD(  PIPELINE_SELECT,                  S3D,    F,  1,      S  ),
286 	CMD(  MEDIA_VFE_STATE,			S3D,   !F,  0xFFFF, B,
287 	      .bits = {{
288 			.offset = 2,
289 			.mask = MEDIA_VFE_STATE_MMIO_ACCESS_MASK,
290 			.expected = 0,
291 	      }},						       ),
292 	CMD(  GPGPU_OBJECT,                     S3D,   !F,  0xFF,   S  ),
293 	CMD(  GPGPU_WALKER,                     S3D,   !F,  0xFF,   S  ),
294 	CMD(  GFX_OP_3DSTATE_SO_DECL_LIST,      S3D,   !F,  0x1FF,  S  ),
295 	CMD(  GFX_OP_PIPE_CONTROL(5),           S3D,   !F,  0xFF,   B,
296 	      .bits = {{
297 			.offset = 1,
298 			.mask = (PIPE_CONTROL_MMIO_WRITE | PIPE_CONTROL_NOTIFY),
299 			.expected = 0,
300 	      },
301 	      {
302 			.offset = 1,
303 		        .mask = (PIPE_CONTROL_GLOBAL_GTT_IVB |
304 				 PIPE_CONTROL_STORE_DATA_INDEX),
305 			.expected = 0,
306 			.condition_offset = 1,
307 			.condition_mask = PIPE_CONTROL_POST_SYNC_OP_MASK,
308 	      }},						       ),
309 };
310 
311 static const struct drm_i915_cmd_descriptor hsw_render_cmds[] = {
312 	CMD(  MI_SET_PREDICATE,                 SMI,    F,  1,      S  ),
313 	CMD(  MI_RS_CONTROL,                    SMI,    F,  1,      S  ),
314 	CMD(  MI_URB_ATOMIC_ALLOC,              SMI,    F,  1,      S  ),
315 	CMD(  MI_SET_APPID,                     SMI,    F,  1,      S  ),
316 	CMD(  MI_RS_CONTEXT,                    SMI,    F,  1,      S  ),
317 	CMD(  MI_LOAD_SCAN_LINES_INCL,          SMI,   !F,  0x3F,   R  ),
318 	CMD(  MI_LOAD_SCAN_LINES_EXCL,          SMI,   !F,  0x3F,   R  ),
319 	CMD(  MI_LOAD_REGISTER_REG,             SMI,   !F,  0xFF,   W,
320 	      .reg = { .offset = 1, .mask = 0x007FFFFC, .step = 1 }    ),
321 	CMD(  MI_RS_STORE_DATA_IMM,             SMI,   !F,  0xFF,   S  ),
322 	CMD(  MI_LOAD_URB_MEM,                  SMI,   !F,  0xFF,   S  ),
323 	CMD(  MI_STORE_URB_MEM,                 SMI,   !F,  0xFF,   S  ),
324 	CMD(  GFX_OP_3DSTATE_DX9_CONSTANTF_VS,  S3D,   !F,  0x7FF,  S  ),
325 	CMD(  GFX_OP_3DSTATE_DX9_CONSTANTF_PS,  S3D,   !F,  0x7FF,  S  ),
326 
327 	CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_VS,  S3D,   !F,  0x1FF,  S  ),
328 	CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_GS,  S3D,   !F,  0x1FF,  S  ),
329 	CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_HS,  S3D,   !F,  0x1FF,  S  ),
330 	CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_DS,  S3D,   !F,  0x1FF,  S  ),
331 	CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_PS,  S3D,   !F,  0x1FF,  S  ),
332 };
333 
334 static const struct drm_i915_cmd_descriptor gen7_video_cmds[] = {
335 	CMD(  MI_ARB_ON_OFF,                    SMI,    F,  1,      R  ),
336 	CMD(  MI_SET_APPID,                     SMI,    F,  1,      S  ),
337 	CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0xFF,   B,
338 	      .bits = {{
339 			.offset = 0,
340 			.mask = MI_GLOBAL_GTT,
341 			.expected = 0,
342 	      }},						       ),
343 	CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0x3F,   R  ),
344 	CMD(  MI_FLUSH_DW,                      SMI,   !F,  0x3F,   B,
345 	      .bits = {{
346 			.offset = 0,
347 			.mask = MI_FLUSH_DW_NOTIFY,
348 			.expected = 0,
349 	      },
350 	      {
351 			.offset = 1,
352 			.mask = MI_FLUSH_DW_USE_GTT,
353 			.expected = 0,
354 			.condition_offset = 0,
355 			.condition_mask = MI_FLUSH_DW_OP_MASK,
356 	      },
357 	      {
358 			.offset = 0,
359 			.mask = MI_FLUSH_DW_STORE_INDEX,
360 			.expected = 0,
361 			.condition_offset = 0,
362 			.condition_mask = MI_FLUSH_DW_OP_MASK,
363 	      }},						       ),
364 	CMD(  MI_CONDITIONAL_BATCH_BUFFER_END,  SMI,   !F,  0xFF,   B,
365 	      .bits = {{
366 			.offset = 0,
367 			.mask = MI_GLOBAL_GTT,
368 			.expected = 0,
369 	      }},						       ),
370 	/*
371 	 * MFX_WAIT doesn't fit the way we handle length for most commands.
372 	 * It has a length field but it uses a non-standard length bias.
373 	 * It is always 1 dword though, so just treat it as fixed length.
374 	 */
375 	CMD(  MFX_WAIT,                         SMFX,   F,  1,      S  ),
376 };
377 
378 static const struct drm_i915_cmd_descriptor gen7_vecs_cmds[] = {
379 	CMD(  MI_ARB_ON_OFF,                    SMI,    F,  1,      R  ),
380 	CMD(  MI_SET_APPID,                     SMI,    F,  1,      S  ),
381 	CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0xFF,   B,
382 	      .bits = {{
383 			.offset = 0,
384 			.mask = MI_GLOBAL_GTT,
385 			.expected = 0,
386 	      }},						       ),
387 	CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0x3F,   R  ),
388 	CMD(  MI_FLUSH_DW,                      SMI,   !F,  0x3F,   B,
389 	      .bits = {{
390 			.offset = 0,
391 			.mask = MI_FLUSH_DW_NOTIFY,
392 			.expected = 0,
393 	      },
394 	      {
395 			.offset = 1,
396 			.mask = MI_FLUSH_DW_USE_GTT,
397 			.expected = 0,
398 			.condition_offset = 0,
399 			.condition_mask = MI_FLUSH_DW_OP_MASK,
400 	      },
401 	      {
402 			.offset = 0,
403 			.mask = MI_FLUSH_DW_STORE_INDEX,
404 			.expected = 0,
405 			.condition_offset = 0,
406 			.condition_mask = MI_FLUSH_DW_OP_MASK,
407 	      }},						       ),
408 	CMD(  MI_CONDITIONAL_BATCH_BUFFER_END,  SMI,   !F,  0xFF,   B,
409 	      .bits = {{
410 			.offset = 0,
411 			.mask = MI_GLOBAL_GTT,
412 			.expected = 0,
413 	      }},						       ),
414 };
415 
416 static const struct drm_i915_cmd_descriptor gen7_blt_cmds[] = {
417 	CMD(  MI_DISPLAY_FLIP,                  SMI,   !F,  0xFF,   R  ),
418 	CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0x3FF,  B,
419 	      .bits = {{
420 			.offset = 0,
421 			.mask = MI_GLOBAL_GTT,
422 			.expected = 0,
423 	      }},						       ),
424 	CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0x3F,   R  ),
425 	CMD(  MI_FLUSH_DW,                      SMI,   !F,  0x3F,   B,
426 	      .bits = {{
427 			.offset = 0,
428 			.mask = MI_FLUSH_DW_NOTIFY,
429 			.expected = 0,
430 	      },
431 	      {
432 			.offset = 1,
433 			.mask = MI_FLUSH_DW_USE_GTT,
434 			.expected = 0,
435 			.condition_offset = 0,
436 			.condition_mask = MI_FLUSH_DW_OP_MASK,
437 	      },
438 	      {
439 			.offset = 0,
440 			.mask = MI_FLUSH_DW_STORE_INDEX,
441 			.expected = 0,
442 			.condition_offset = 0,
443 			.condition_mask = MI_FLUSH_DW_OP_MASK,
444 	      }},						       ),
445 	CMD(  COLOR_BLT,                        S2D,   !F,  0x3F,   S  ),
446 	CMD(  SRC_COPY_BLT,                     S2D,   !F,  0x3F,   S  ),
447 };
448 
449 static const struct drm_i915_cmd_descriptor hsw_blt_cmds[] = {
450 	CMD(  MI_LOAD_SCAN_LINES_INCL,          SMI,   !F,  0x3F,   R  ),
451 	CMD(  MI_LOAD_SCAN_LINES_EXCL,          SMI,   !F,  0x3F,   R  ),
452 };
453 
454 /*
455  * For Gen9 we can still rely on the h/w to enforce cmd security, and only
456  * need to re-enforce the register access checks. We therefore only need to
457  * teach the cmdparser how to find the end of each command, and identify
458  * register accesses. The table doesn't need to reject any commands, and so
459  * the only commands listed here are:
460  *   1) Those that touch registers
461  *   2) Those that do not have the default 8-bit length
462  *
463  * Note that the default MI length mask chosen for this table is 0xFF, not
464  * the 0x3F used on older devices. This is because the vast majority of MI
465  * cmds on Gen9 use a standard 8-bit Length field.
466  * All the Gen9 blitter instructions are standard 0xFF length mask, and
467  * none allow access to non-general registers, so in fact no BLT cmds are
468  * included in the table at all.
469  *
470  */
471 static const struct drm_i915_cmd_descriptor gen9_blt_cmds[] = {
472 	CMD(  MI_NOOP,                          SMI,    F,  1,      S  ),
473 	CMD(  MI_USER_INTERRUPT,                SMI,    F,  1,      S  ),
474 	CMD(  MI_WAIT_FOR_EVENT,                SMI,    F,  1,      S  ),
475 	CMD(  MI_FLUSH,                         SMI,    F,  1,      S  ),
476 	CMD(  MI_ARB_CHECK,                     SMI,    F,  1,      S  ),
477 	CMD(  MI_REPORT_HEAD,                   SMI,    F,  1,      S  ),
478 	CMD(  MI_ARB_ON_OFF,                    SMI,    F,  1,      S  ),
479 	CMD(  MI_SUSPEND_FLUSH,                 SMI,    F,  1,      S  ),
480 	CMD(  MI_LOAD_SCAN_LINES_INCL,          SMI,   !F,  0x3F,   S  ),
481 	CMD(  MI_LOAD_SCAN_LINES_EXCL,          SMI,   !F,  0x3F,   S  ),
482 	CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0x3FF,  S  ),
483 	CMD(  MI_LOAD_REGISTER_IMM(1),          SMI,   !F,  0xFF,   W,
484 	      .reg = { .offset = 1, .mask = 0x007FFFFC, .step = 2 }    ),
485 	CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0x3FF,  S  ),
486 	CMD(  MI_STORE_REGISTER_MEM_GEN8,       SMI,    F,  4,      W,
487 	      .reg = { .offset = 1, .mask = 0x007FFFFC }               ),
488 	CMD(  MI_FLUSH_DW,                      SMI,   !F,  0x3F,   S  ),
489 	CMD(  MI_LOAD_REGISTER_MEM_GEN8,        SMI,    F,  4,      W,
490 	      .reg = { .offset = 1, .mask = 0x007FFFFC }               ),
491 	CMD(  MI_LOAD_REGISTER_REG,             SMI,    !F,  0xFF,  W,
492 	      .reg = { .offset = 1, .mask = 0x007FFFFC, .step = 1 }    ),
493 
494 	/*
495 	 * We allow BB_START but apply further checks. We just sanitize the
496 	 * basic fields here.
497 	 */
498 #define MI_BB_START_OPERAND_MASK   GENMASK(SMI-1, 0)
499 #define MI_BB_START_OPERAND_EXPECT (MI_BATCH_PPGTT_HSW | 1)
500 	CMD(  MI_BATCH_BUFFER_START_GEN8,       SMI,    !F,  0xFF,  B,
501 	      .bits = {{
502 			.offset = 0,
503 			.mask = MI_BB_START_OPERAND_MASK,
504 			.expected = MI_BB_START_OPERAND_EXPECT,
505 	      }},						       ),
506 };
507 
508 static const struct drm_i915_cmd_descriptor noop_desc =
509 	CMD(MI_NOOP, SMI, F, 1, S);
510 
511 #undef CMD
512 #undef SMI
513 #undef S3D
514 #undef S2D
515 #undef SMFX
516 #undef F
517 #undef S
518 #undef R
519 #undef W
520 #undef B
521 
522 static const struct drm_i915_cmd_table gen7_render_cmd_table[] = {
523 	{ gen7_common_cmds, ARRAY_SIZE(gen7_common_cmds) },
524 	{ gen7_render_cmds, ARRAY_SIZE(gen7_render_cmds) },
525 };
526 
527 static const struct drm_i915_cmd_table hsw_render_ring_cmd_table[] = {
528 	{ gen7_common_cmds, ARRAY_SIZE(gen7_common_cmds) },
529 	{ gen7_render_cmds, ARRAY_SIZE(gen7_render_cmds) },
530 	{ hsw_render_cmds, ARRAY_SIZE(hsw_render_cmds) },
531 };
532 
533 static const struct drm_i915_cmd_table gen7_video_cmd_table[] = {
534 	{ gen7_common_cmds, ARRAY_SIZE(gen7_common_cmds) },
535 	{ gen7_video_cmds, ARRAY_SIZE(gen7_video_cmds) },
536 };
537 
538 static const struct drm_i915_cmd_table hsw_vebox_cmd_table[] = {
539 	{ gen7_common_cmds, ARRAY_SIZE(gen7_common_cmds) },
540 	{ gen7_vecs_cmds, ARRAY_SIZE(gen7_vecs_cmds) },
541 };
542 
543 static const struct drm_i915_cmd_table gen7_blt_cmd_table[] = {
544 	{ gen7_common_cmds, ARRAY_SIZE(gen7_common_cmds) },
545 	{ gen7_blt_cmds, ARRAY_SIZE(gen7_blt_cmds) },
546 };
547 
548 static const struct drm_i915_cmd_table hsw_blt_ring_cmd_table[] = {
549 	{ gen7_common_cmds, ARRAY_SIZE(gen7_common_cmds) },
550 	{ gen7_blt_cmds, ARRAY_SIZE(gen7_blt_cmds) },
551 	{ hsw_blt_cmds, ARRAY_SIZE(hsw_blt_cmds) },
552 };
553 
554 static const struct drm_i915_cmd_table gen9_blt_cmd_table[] = {
555 	{ gen9_blt_cmds, ARRAY_SIZE(gen9_blt_cmds) },
556 };
557 
558 
559 /*
560  * Register whitelists, sorted by increasing register offset.
561  */
562 
563 /*
564  * An individual whitelist entry granting access to register addr.  If
565  * mask is non-zero the argument of immediate register writes will be
566  * AND-ed with mask, and the command will be rejected if the result
567  * doesn't match value.
568  *
569  * Registers with non-zero mask are only allowed to be written using
570  * LRI.
571  */
572 struct drm_i915_reg_descriptor {
573 	i915_reg_t addr;
574 	u32 mask;
575 	u32 value;
576 };
577 
578 /* Convenience macro for adding 32-bit registers. */
579 #define REG32(_reg, ...) \
580 	{ .addr = (_reg), __VA_ARGS__ }
581 
582 /*
583  * Convenience macro for adding 64-bit registers.
584  *
585  * Some registers that userspace accesses are 64 bits. The register
586  * access commands only allow 32-bit accesses. Hence, we have to include
587  * entries for both halves of the 64-bit registers.
588  */
589 #define REG64(_reg) \
590 	{ .addr = _reg }, \
591 	{ .addr = _reg ## _UDW }
592 
593 #define REG64_IDX(_reg, idx) \
594 	{ .addr = _reg(idx) }, \
595 	{ .addr = _reg ## _UDW(idx) }
596 
597 static const struct drm_i915_reg_descriptor gen7_render_regs[] = {
598 	REG64(GPGPU_THREADS_DISPATCHED),
599 	REG64(HS_INVOCATION_COUNT),
600 	REG64(DS_INVOCATION_COUNT),
601 	REG64(IA_VERTICES_COUNT),
602 	REG64(IA_PRIMITIVES_COUNT),
603 	REG64(VS_INVOCATION_COUNT),
604 	REG64(GS_INVOCATION_COUNT),
605 	REG64(GS_PRIMITIVES_COUNT),
606 	REG64(CL_INVOCATION_COUNT),
607 	REG64(CL_PRIMITIVES_COUNT),
608 	REG64(PS_INVOCATION_COUNT),
609 	REG64(PS_DEPTH_COUNT),
610 	REG64_IDX(RING_TIMESTAMP, RENDER_RING_BASE),
611 	REG64(MI_PREDICATE_SRC0),
612 	REG64(MI_PREDICATE_SRC1),
613 	REG32(GEN7_3DPRIM_END_OFFSET),
614 	REG32(GEN7_3DPRIM_START_VERTEX),
615 	REG32(GEN7_3DPRIM_VERTEX_COUNT),
616 	REG32(GEN7_3DPRIM_INSTANCE_COUNT),
617 	REG32(GEN7_3DPRIM_START_INSTANCE),
618 	REG32(GEN7_3DPRIM_BASE_VERTEX),
619 	REG32(GEN7_GPGPU_DISPATCHDIMX),
620 	REG32(GEN7_GPGPU_DISPATCHDIMY),
621 	REG32(GEN7_GPGPU_DISPATCHDIMZ),
622 	REG64_IDX(RING_TIMESTAMP, BSD_RING_BASE),
623 	REG64_IDX(GEN7_SO_NUM_PRIMS_WRITTEN, 0),
624 	REG64_IDX(GEN7_SO_NUM_PRIMS_WRITTEN, 1),
625 	REG64_IDX(GEN7_SO_NUM_PRIMS_WRITTEN, 2),
626 	REG64_IDX(GEN7_SO_NUM_PRIMS_WRITTEN, 3),
627 	REG64_IDX(GEN7_SO_PRIM_STORAGE_NEEDED, 0),
628 	REG64_IDX(GEN7_SO_PRIM_STORAGE_NEEDED, 1),
629 	REG64_IDX(GEN7_SO_PRIM_STORAGE_NEEDED, 2),
630 	REG64_IDX(GEN7_SO_PRIM_STORAGE_NEEDED, 3),
631 	REG32(GEN7_SO_WRITE_OFFSET(0)),
632 	REG32(GEN7_SO_WRITE_OFFSET(1)),
633 	REG32(GEN7_SO_WRITE_OFFSET(2)),
634 	REG32(GEN7_SO_WRITE_OFFSET(3)),
635 	REG32(GEN7_L3SQCREG1),
636 	REG32(GEN7_L3CNTLREG2),
637 	REG32(GEN7_L3CNTLREG3),
638 	REG64_IDX(RING_TIMESTAMP, BLT_RING_BASE),
639 };
640 
641 static const struct drm_i915_reg_descriptor hsw_render_regs[] = {
642 	REG64_IDX(HSW_CS_GPR, 0),
643 	REG64_IDX(HSW_CS_GPR, 1),
644 	REG64_IDX(HSW_CS_GPR, 2),
645 	REG64_IDX(HSW_CS_GPR, 3),
646 	REG64_IDX(HSW_CS_GPR, 4),
647 	REG64_IDX(HSW_CS_GPR, 5),
648 	REG64_IDX(HSW_CS_GPR, 6),
649 	REG64_IDX(HSW_CS_GPR, 7),
650 	REG64_IDX(HSW_CS_GPR, 8),
651 	REG64_IDX(HSW_CS_GPR, 9),
652 	REG64_IDX(HSW_CS_GPR, 10),
653 	REG64_IDX(HSW_CS_GPR, 11),
654 	REG64_IDX(HSW_CS_GPR, 12),
655 	REG64_IDX(HSW_CS_GPR, 13),
656 	REG64_IDX(HSW_CS_GPR, 14),
657 	REG64_IDX(HSW_CS_GPR, 15),
658 	REG32(HSW_SCRATCH1,
659 	      .mask = ~HSW_SCRATCH1_L3_DATA_ATOMICS_DISABLE,
660 	      .value = 0),
661 	REG32(HSW_ROW_CHICKEN3,
662 	      .mask = ~(HSW_ROW_CHICKEN3_L3_GLOBAL_ATOMICS_DISABLE << 16 |
663                         HSW_ROW_CHICKEN3_L3_GLOBAL_ATOMICS_DISABLE),
664 	      .value = 0),
665 };
666 
667 static const struct drm_i915_reg_descriptor gen7_blt_regs[] = {
668 	REG64_IDX(RING_TIMESTAMP, RENDER_RING_BASE),
669 	REG64_IDX(RING_TIMESTAMP, BSD_RING_BASE),
670 	REG32(BCS_SWCTRL),
671 	REG64_IDX(RING_TIMESTAMP, BLT_RING_BASE),
672 };
673 
674 static const struct drm_i915_reg_descriptor gen9_blt_regs[] = {
675 	REG64_IDX(RING_TIMESTAMP, RENDER_RING_BASE),
676 	REG64_IDX(RING_TIMESTAMP, BSD_RING_BASE),
677 	REG32(BCS_SWCTRL),
678 	REG64_IDX(RING_TIMESTAMP, BLT_RING_BASE),
679 	REG64_IDX(BCS_GPR, 0),
680 	REG64_IDX(BCS_GPR, 1),
681 	REG64_IDX(BCS_GPR, 2),
682 	REG64_IDX(BCS_GPR, 3),
683 	REG64_IDX(BCS_GPR, 4),
684 	REG64_IDX(BCS_GPR, 5),
685 	REG64_IDX(BCS_GPR, 6),
686 	REG64_IDX(BCS_GPR, 7),
687 	REG64_IDX(BCS_GPR, 8),
688 	REG64_IDX(BCS_GPR, 9),
689 	REG64_IDX(BCS_GPR, 10),
690 	REG64_IDX(BCS_GPR, 11),
691 	REG64_IDX(BCS_GPR, 12),
692 	REG64_IDX(BCS_GPR, 13),
693 	REG64_IDX(BCS_GPR, 14),
694 	REG64_IDX(BCS_GPR, 15),
695 };
696 
697 #undef REG64
698 #undef REG32
699 
700 struct drm_i915_reg_table {
701 	const struct drm_i915_reg_descriptor *regs;
702 	int num_regs;
703 };
704 
705 static const struct drm_i915_reg_table ivb_render_reg_tables[] = {
706 	{ gen7_render_regs, ARRAY_SIZE(gen7_render_regs) },
707 };
708 
709 static const struct drm_i915_reg_table ivb_blt_reg_tables[] = {
710 	{ gen7_blt_regs, ARRAY_SIZE(gen7_blt_regs) },
711 };
712 
713 static const struct drm_i915_reg_table hsw_render_reg_tables[] = {
714 	{ gen7_render_regs, ARRAY_SIZE(gen7_render_regs) },
715 	{ hsw_render_regs, ARRAY_SIZE(hsw_render_regs) },
716 };
717 
718 static const struct drm_i915_reg_table hsw_blt_reg_tables[] = {
719 	{ gen7_blt_regs, ARRAY_SIZE(gen7_blt_regs) },
720 };
721 
722 static const struct drm_i915_reg_table gen9_blt_reg_tables[] = {
723 	{ gen9_blt_regs, ARRAY_SIZE(gen9_blt_regs) },
724 };
725 
gen7_render_get_cmd_length_mask(u32 cmd_header)726 static u32 gen7_render_get_cmd_length_mask(u32 cmd_header)
727 {
728 	u32 client = cmd_header >> INSTR_CLIENT_SHIFT;
729 	u32 subclient =
730 		(cmd_header & INSTR_SUBCLIENT_MASK) >> INSTR_SUBCLIENT_SHIFT;
731 
732 	if (client == INSTR_MI_CLIENT)
733 		return 0x3F;
734 	else if (client == INSTR_RC_CLIENT) {
735 		if (subclient == INSTR_MEDIA_SUBCLIENT)
736 			return 0xFFFF;
737 		else
738 			return 0xFF;
739 	}
740 
741 	DRM_DEBUG("CMD: Abnormal rcs cmd length! 0x%08X\n", cmd_header);
742 	return 0;
743 }
744 
gen7_bsd_get_cmd_length_mask(u32 cmd_header)745 static u32 gen7_bsd_get_cmd_length_mask(u32 cmd_header)
746 {
747 	u32 client = cmd_header >> INSTR_CLIENT_SHIFT;
748 	u32 subclient =
749 		(cmd_header & INSTR_SUBCLIENT_MASK) >> INSTR_SUBCLIENT_SHIFT;
750 	u32 op = (cmd_header & INSTR_26_TO_24_MASK) >> INSTR_26_TO_24_SHIFT;
751 
752 	if (client == INSTR_MI_CLIENT)
753 		return 0x3F;
754 	else if (client == INSTR_RC_CLIENT) {
755 		if (subclient == INSTR_MEDIA_SUBCLIENT) {
756 			if (op == 6)
757 				return 0xFFFF;
758 			else
759 				return 0xFFF;
760 		} else
761 			return 0xFF;
762 	}
763 
764 	DRM_DEBUG("CMD: Abnormal bsd cmd length! 0x%08X\n", cmd_header);
765 	return 0;
766 }
767 
gen7_blt_get_cmd_length_mask(u32 cmd_header)768 static u32 gen7_blt_get_cmd_length_mask(u32 cmd_header)
769 {
770 	u32 client = cmd_header >> INSTR_CLIENT_SHIFT;
771 
772 	if (client == INSTR_MI_CLIENT)
773 		return 0x3F;
774 	else if (client == INSTR_BC_CLIENT)
775 		return 0xFF;
776 
777 	DRM_DEBUG("CMD: Abnormal blt cmd length! 0x%08X\n", cmd_header);
778 	return 0;
779 }
780 
gen9_blt_get_cmd_length_mask(u32 cmd_header)781 static u32 gen9_blt_get_cmd_length_mask(u32 cmd_header)
782 {
783 	u32 client = cmd_header >> INSTR_CLIENT_SHIFT;
784 
785 	if (client == INSTR_MI_CLIENT || client == INSTR_BC_CLIENT)
786 		return 0xFF;
787 
788 	DRM_DEBUG("CMD: Abnormal blt cmd length! 0x%08X\n", cmd_header);
789 	return 0;
790 }
791 
validate_cmds_sorted(const struct intel_engine_cs * engine,const struct drm_i915_cmd_table * cmd_tables,int cmd_table_count)792 static bool validate_cmds_sorted(const struct intel_engine_cs *engine,
793 				 const struct drm_i915_cmd_table *cmd_tables,
794 				 int cmd_table_count)
795 {
796 	int i;
797 	bool ret = true;
798 
799 	if (!cmd_tables || cmd_table_count == 0)
800 		return true;
801 
802 	for (i = 0; i < cmd_table_count; i++) {
803 		const struct drm_i915_cmd_table *table = &cmd_tables[i];
804 		u32 previous = 0;
805 		int j;
806 
807 		for (j = 0; j < table->count; j++) {
808 			const struct drm_i915_cmd_descriptor *desc =
809 				&table->table[j];
810 			u32 curr = desc->cmd.value & desc->cmd.mask;
811 
812 			if (curr < previous) {
813 				DRM_ERROR("CMD: %s [%d] command table not sorted: "
814 					  "table=%d entry=%d cmd=0x%08X prev=0x%08X\n",
815 					  engine->name, engine->id,
816 					  i, j, curr, previous);
817 				ret = false;
818 			}
819 
820 			previous = curr;
821 		}
822 	}
823 
824 	return ret;
825 }
826 
check_sorted(const struct intel_engine_cs * engine,const struct drm_i915_reg_descriptor * reg_table,int reg_count)827 static bool check_sorted(const struct intel_engine_cs *engine,
828 			 const struct drm_i915_reg_descriptor *reg_table,
829 			 int reg_count)
830 {
831 	int i;
832 	u32 previous = 0;
833 	bool ret = true;
834 
835 	for (i = 0; i < reg_count; i++) {
836 		u32 curr = i915_mmio_reg_offset(reg_table[i].addr);
837 
838 		if (curr < previous) {
839 			DRM_ERROR("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 void 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 (!IS_GEN(engine->i915, 7) && !(IS_GEN(engine->i915, 9) &&
950 					  engine->class == COPY_ENGINE_CLASS))
951 		return;
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 (IS_GEN(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 (IS_GEN(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 		return;
1017 	}
1018 
1019 	if (!validate_cmds_sorted(engine, cmd_tables, cmd_table_count)) {
1020 		DRM_ERROR("%s: command descriptions are not sorted\n",
1021 			  engine->name);
1022 		return;
1023 	}
1024 	if (!validate_regs_sorted(engine)) {
1025 		DRM_ERROR("%s: registers are not sorted\n", engine->name);
1026 		return;
1027 	}
1028 
1029 	ret = init_hash_table(engine, cmd_tables, cmd_table_count);
1030 	if (ret) {
1031 		DRM_ERROR("%s: initialised failed!\n", engine->name);
1032 		fini_hash_table(engine);
1033 		return;
1034 	}
1035 
1036 	engine->flags |= I915_ENGINE_USING_CMD_PARSER;
1037 }
1038 
1039 /**
1040  * intel_engine_cleanup_cmd_parser() - clean up cmd parser related fields
1041  * @engine: the engine to clean up
1042  *
1043  * Releases any resources related to command parsing that may have been
1044  * initialized for the specified engine.
1045  */
intel_engine_cleanup_cmd_parser(struct intel_engine_cs * engine)1046 void intel_engine_cleanup_cmd_parser(struct intel_engine_cs *engine)
1047 {
1048 	if (!intel_engine_using_cmd_parser(engine))
1049 		return;
1050 
1051 	fini_hash_table(engine);
1052 }
1053 
1054 static const struct drm_i915_cmd_descriptor*
find_cmd_in_table(struct intel_engine_cs * engine,u32 cmd_header)1055 find_cmd_in_table(struct intel_engine_cs *engine,
1056 		  u32 cmd_header)
1057 {
1058 	struct cmd_node *desc_node;
1059 
1060 	hash_for_each_possible(engine->cmd_hash, desc_node, node,
1061 			       cmd_header_key(cmd_header)) {
1062 		const struct drm_i915_cmd_descriptor *desc = desc_node->desc;
1063 		if (((cmd_header ^ desc->cmd.value) & desc->cmd.mask) == 0)
1064 			return desc;
1065 	}
1066 
1067 	return NULL;
1068 }
1069 
1070 /*
1071  * Returns a pointer to a descriptor for the command specified by cmd_header.
1072  *
1073  * The caller must supply space for a default descriptor via the default_desc
1074  * parameter. If no descriptor for the specified command exists in the engine's
1075  * command parser tables, this function fills in default_desc based on the
1076  * engine's default length encoding and returns default_desc.
1077  */
1078 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)1079 find_cmd(struct intel_engine_cs *engine,
1080 	 u32 cmd_header,
1081 	 const struct drm_i915_cmd_descriptor *desc,
1082 	 struct drm_i915_cmd_descriptor *default_desc)
1083 {
1084 	u32 mask;
1085 
1086 	if (((cmd_header ^ desc->cmd.value) & desc->cmd.mask) == 0)
1087 		return desc;
1088 
1089 	desc = find_cmd_in_table(engine, cmd_header);
1090 	if (desc)
1091 		return desc;
1092 
1093 	mask = engine->get_cmd_length_mask(cmd_header);
1094 	if (!mask)
1095 		return NULL;
1096 
1097 	default_desc->cmd.value = cmd_header;
1098 	default_desc->cmd.mask = ~0u << MIN_OPCODE_SHIFT;
1099 	default_desc->length.mask = mask;
1100 	default_desc->flags = CMD_DESC_SKIP;
1101 	return default_desc;
1102 }
1103 
1104 static const struct drm_i915_reg_descriptor *
__find_reg(const struct drm_i915_reg_descriptor * table,int count,u32 addr)1105 __find_reg(const struct drm_i915_reg_descriptor *table, int count, u32 addr)
1106 {
1107 	int start = 0, end = count;
1108 	while (start < end) {
1109 		int mid = start + (end - start) / 2;
1110 		int ret = addr - i915_mmio_reg_offset(table[mid].addr);
1111 		if (ret < 0)
1112 			end = mid;
1113 		else if (ret > 0)
1114 			start = mid + 1;
1115 		else
1116 			return &table[mid];
1117 	}
1118 	return NULL;
1119 }
1120 
1121 static const struct drm_i915_reg_descriptor *
find_reg(const struct intel_engine_cs * engine,u32 addr)1122 find_reg(const struct intel_engine_cs *engine, u32 addr)
1123 {
1124 	const struct drm_i915_reg_table *table = engine->reg_tables;
1125 	const struct drm_i915_reg_descriptor *reg = NULL;
1126 	int count = engine->reg_table_count;
1127 
1128 	for (; !reg && (count > 0); ++table, --count)
1129 		reg = __find_reg(table->regs, table->num_regs, addr);
1130 
1131 	return reg;
1132 }
1133 
1134 /* 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,u32 offset,u32 length)1135 static u32 *copy_batch(struct drm_i915_gem_object *dst_obj,
1136 		       struct drm_i915_gem_object *src_obj,
1137 		       u32 offset, u32 length)
1138 {
1139 	bool needs_clflush;
1140 	void *dst, *src;
1141 	int ret;
1142 
1143 	dst = i915_gem_object_pin_map(dst_obj, I915_MAP_FORCE_WB);
1144 	if (IS_ERR(dst))
1145 		return dst;
1146 
1147 	ret = i915_gem_object_pin_pages(src_obj);
1148 	if (ret) {
1149 		i915_gem_object_unpin_map(dst_obj);
1150 		return ERR_PTR(ret);
1151 	}
1152 
1153 	needs_clflush =
1154 		!(src_obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_READ);
1155 
1156 	src = ERR_PTR(-ENODEV);
1157 	if (needs_clflush && i915_has_memcpy_from_wc()) {
1158 		src = i915_gem_object_pin_map(src_obj, I915_MAP_WC);
1159 		if (!IS_ERR(src)) {
1160 			i915_unaligned_memcpy_from_wc(dst,
1161 						      src + offset,
1162 						      length);
1163 			i915_gem_object_unpin_map(src_obj);
1164 		}
1165 	}
1166 	if (IS_ERR(src)) {
1167 		void *ptr;
1168 		int x, n;
1169 
1170 		/*
1171 		 * We can avoid clflushing partial cachelines before the write
1172 		 * if we only every write full cache-lines. Since we know that
1173 		 * both the source and destination are in multiples of
1174 		 * PAGE_SIZE, we can simply round up to the next cacheline.
1175 		 * We don't care about copying too much here as we only
1176 		 * validate up to the end of the batch.
1177 		 */
1178 		if (!(dst_obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_READ)) {
1179 #ifdef __NetBSD__
1180 			length = round_up(length,
1181 					  cpu_info_primary.ci_cflush_lsize);
1182 #else
1183 			length = round_up(length,
1184 					  boot_cpu_data.x86_clflush_size);
1185 #endif
1186 		}
1187 
1188 		ptr = dst;
1189 		x = offset_in_page(offset);
1190 		for (n = offset >> PAGE_SHIFT; length; n++) {
1191 			int len = min_t(int, length, PAGE_SIZE - x);
1192 
1193 			src = kmap_atomic(i915_gem_object_get_page(src_obj, n));
1194 			if (needs_clflush)
1195 				drm_clflush_virt_range(src + x, len);
1196 			memcpy(ptr, src + x, len);
1197 			kunmap_atomic(src);
1198 
1199 			ptr += len;
1200 			length -= len;
1201 			x = 0;
1202 		}
1203 	}
1204 
1205 	i915_gem_object_unpin_pages(src_obj);
1206 
1207 	/* dst_obj is returned with vmap pinned */
1208 	return dst;
1209 }
1210 
check_cmd(const struct intel_engine_cs * engine,const struct drm_i915_cmd_descriptor * desc,const u32 * cmd,u32 length)1211 static bool check_cmd(const struct intel_engine_cs *engine,
1212 		      const struct drm_i915_cmd_descriptor *desc,
1213 		      const u32 *cmd, u32 length)
1214 {
1215 	if (desc->flags & CMD_DESC_SKIP)
1216 		return true;
1217 
1218 	if (desc->flags & CMD_DESC_REJECT) {
1219 		DRM_DEBUG("CMD: Rejected command: 0x%08X\n", *cmd);
1220 		return false;
1221 	}
1222 
1223 	if (desc->flags & CMD_DESC_REGISTER) {
1224 		/*
1225 		 * Get the distance between individual register offset
1226 		 * fields if the command can perform more than one
1227 		 * access at a time.
1228 		 */
1229 		const u32 step = desc->reg.step ? desc->reg.step : length;
1230 		u32 offset;
1231 
1232 		for (offset = desc->reg.offset; offset < length;
1233 		     offset += step) {
1234 			const u32 reg_addr = cmd[offset] & desc->reg.mask;
1235 			const struct drm_i915_reg_descriptor *reg =
1236 				find_reg(engine, reg_addr);
1237 
1238 			if (!reg) {
1239 				DRM_DEBUG("CMD: Rejected register 0x%08X in command: 0x%08X (%s)\n",
1240 					  reg_addr, *cmd, engine->name);
1241 				return false;
1242 			}
1243 
1244 			/*
1245 			 * Check the value written to the register against the
1246 			 * allowed mask/value pair given in the whitelist entry.
1247 			 */
1248 			if (reg->mask) {
1249 				if (desc->cmd.value == MI_LOAD_REGISTER_MEM) {
1250 					DRM_DEBUG("CMD: Rejected LRM to masked register 0x%08X\n",
1251 						  reg_addr);
1252 					return false;
1253 				}
1254 
1255 				if (desc->cmd.value == MI_LOAD_REGISTER_REG) {
1256 					DRM_DEBUG("CMD: Rejected LRR to masked register 0x%08X\n",
1257 						  reg_addr);
1258 					return false;
1259 				}
1260 
1261 				if (desc->cmd.value == MI_LOAD_REGISTER_IMM(1) &&
1262 				    (offset + 2 > length ||
1263 				     (cmd[offset + 1] & reg->mask) != reg->value)) {
1264 					DRM_DEBUG("CMD: Rejected LRI to masked register 0x%08X\n",
1265 						  reg_addr);
1266 					return false;
1267 				}
1268 			}
1269 		}
1270 	}
1271 
1272 	if (desc->flags & CMD_DESC_BITMASK) {
1273 		int i;
1274 
1275 		for (i = 0; i < MAX_CMD_DESC_BITMASKS; i++) {
1276 			u32 dword;
1277 
1278 			if (desc->bits[i].mask == 0)
1279 				break;
1280 
1281 			if (desc->bits[i].condition_mask != 0) {
1282 				u32 offset =
1283 					desc->bits[i].condition_offset;
1284 				u32 condition = cmd[offset] &
1285 					desc->bits[i].condition_mask;
1286 
1287 				if (condition == 0)
1288 					continue;
1289 			}
1290 
1291 			if (desc->bits[i].offset >= length) {
1292 				DRM_DEBUG("CMD: Rejected command 0x%08X, too short to check bitmask (%s)\n",
1293 					  *cmd, engine->name);
1294 				return false;
1295 			}
1296 
1297 			dword = cmd[desc->bits[i].offset] &
1298 				desc->bits[i].mask;
1299 
1300 			if (dword != desc->bits[i].expected) {
1301 				DRM_DEBUG("CMD: Rejected command 0x%08X for bitmask 0x%08X (exp=0x%08X act=0x%08X) (%s)\n",
1302 					  *cmd,
1303 					  desc->bits[i].mask,
1304 					  desc->bits[i].expected,
1305 					  dword, engine->name);
1306 				return false;
1307 			}
1308 		}
1309 	}
1310 
1311 	return true;
1312 }
1313 
check_bbstart(u32 * cmd,u32 offset,u32 length,u32 batch_length,u64 batch_addr,u64 shadow_addr,const unsigned long * jump_whitelist)1314 static int check_bbstart(u32 *cmd, u32 offset, u32 length,
1315 			 u32 batch_length,
1316 			 u64 batch_addr,
1317 			 u64 shadow_addr,
1318 			 const unsigned long *jump_whitelist)
1319 {
1320 	u64 jump_offset, jump_target;
1321 	u32 target_cmd_offset, target_cmd_index;
1322 
1323 	/* For igt compatibility on older platforms */
1324 	if (!jump_whitelist) {
1325 		DRM_DEBUG("CMD: Rejecting BB_START for ggtt based submission\n");
1326 		return -EACCES;
1327 	}
1328 
1329 	if (length != 3) {
1330 		DRM_DEBUG("CMD: Recursive BB_START with bad length(%u)\n",
1331 			  length);
1332 		return -EINVAL;
1333 	}
1334 
1335 	jump_target = *(u64 *)(cmd + 1);
1336 	jump_offset = jump_target - batch_addr;
1337 
1338 	/*
1339 	 * Any underflow of jump_target is guaranteed to be outside the range
1340 	 * of a u32, so >= test catches both too large and too small
1341 	 */
1342 	if (jump_offset >= batch_length) {
1343 		DRM_DEBUG("CMD: BB_START to 0x%"PRIx64" jumps out of BB\n",
1344 			  jump_target);
1345 		return -EINVAL;
1346 	}
1347 
1348 	/*
1349 	 * This cannot overflow a u32 because we already checked jump_offset
1350 	 * is within the BB, and the batch_length is a u32
1351 	 */
1352 	target_cmd_offset = lower_32_bits(jump_offset);
1353 	target_cmd_index = target_cmd_offset / sizeof(u32);
1354 
1355 	*(u64 *)(cmd + 1) = shadow_addr + target_cmd_offset;
1356 
1357 	if (target_cmd_index == offset)
1358 		return 0;
1359 
1360 	if (IS_ERR(jump_whitelist))
1361 		return PTR_ERR(jump_whitelist);
1362 
1363 	if (!test_bit(target_cmd_index, jump_whitelist)) {
1364 		DRM_DEBUG("CMD: BB_START to 0x%"PRIx64" not a previously executed cmd\n",
1365 			  jump_target);
1366 		return -EINVAL;
1367 	}
1368 
1369 	return 0;
1370 }
1371 
alloc_whitelist(u32 batch_length)1372 static unsigned long *alloc_whitelist(u32 batch_length)
1373 {
1374 	unsigned long *jmp;
1375 
1376 	/*
1377 	 * We expect batch_length to be less than 256KiB for known users,
1378 	 * i.e. we need at most an 8KiB bitmap allocation which should be
1379 	 * reasonably cheap due to kmalloc caches.
1380 	 */
1381 
1382 	/* Prefer to report transient allocation failure rather than hit oom */
1383 	jmp = bitmap_zalloc(DIV_ROUND_UP(batch_length, sizeof(u32)),
1384 			    GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN);
1385 	if (!jmp)
1386 		return ERR_PTR(-ENOMEM);
1387 
1388 	return jmp;
1389 }
1390 
1391 #define LENGTH_BIAS 2
1392 
shadow_needs_clflush(struct drm_i915_gem_object * obj)1393 static bool shadow_needs_clflush(struct drm_i915_gem_object *obj)
1394 {
1395 	return !(obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_WRITE);
1396 }
1397 
1398 /**
1399  * intel_engine_cmd_parser() - parse a batch buffer for privilege violations
1400  * @engine: the engine on which the batch is to execute
1401  * @batch: the batch buffer in question
1402  * @batch_offset: byte offset in the batch at which execution starts
1403  * @batch_length: length of the commands in batch_obj
1404  * @shadow: validated copy of the batch buffer in question
1405  * @trampoline: whether to emit a conditional trampoline at the end of the batch
1406  *
1407  * Parses the specified batch buffer looking for privilege violations as
1408  * described in the overview.
1409  *
1410  * Return: non-zero if the parser finds violations or otherwise fails; -EACCES
1411  * if the batch appears legal but should use hardware parsing
1412  */
intel_engine_cmd_parser(struct intel_engine_cs * engine,struct i915_vma * batch,u32 batch_offset,u32 batch_length,struct i915_vma * shadow,bool trampoline)1413 int intel_engine_cmd_parser(struct intel_engine_cs *engine,
1414 			    struct i915_vma *batch,
1415 			    u32 batch_offset,
1416 			    u32 batch_length,
1417 			    struct i915_vma *shadow,
1418 			    bool trampoline)
1419 {
1420 	u32 *cmd, *batch_end, offset = 0;
1421 	struct drm_i915_cmd_descriptor default_desc = noop_desc;
1422 	const struct drm_i915_cmd_descriptor *desc = &default_desc;
1423 	unsigned long *jump_whitelist;
1424 	u64 batch_addr, shadow_addr;
1425 	int ret = 0;
1426 
1427 	GEM_BUG_ON(!IS_ALIGNED(batch_offset, sizeof(*cmd)));
1428 	GEM_BUG_ON(!IS_ALIGNED(batch_length, sizeof(*cmd)));
1429 	GEM_BUG_ON(range_overflows_t(u64, batch_offset, batch_length,
1430 				     batch->size));
1431 	GEM_BUG_ON(!batch_length);
1432 
1433 	cmd = copy_batch(shadow->obj, batch->obj, batch_offset, batch_length);
1434 	if (IS_ERR(cmd)) {
1435 		DRM_DEBUG("CMD: Failed to copy batch\n");
1436 		return PTR_ERR(cmd);
1437 	}
1438 
1439 	jump_whitelist = NULL;
1440 	if (!trampoline)
1441 		/* Defer failure until attempted use */
1442 		jump_whitelist = alloc_whitelist(batch_length);
1443 
1444 	shadow_addr = gen8_canonical_addr(shadow->node.start);
1445 	batch_addr = gen8_canonical_addr(batch->node.start + batch_offset);
1446 
1447 	/*
1448 	 * We use the batch length as size because the shadow object is as
1449 	 * large or larger and copy_batch() will write MI_NOPs to the extra
1450 	 * space. Parsing should be faster in some cases this way.
1451 	 */
1452 	batch_end = cmd + batch_length / sizeof(*batch_end);
1453 	do {
1454 		u32 length;
1455 
1456 		if (*cmd == MI_BATCH_BUFFER_END)
1457 			break;
1458 
1459 		desc = find_cmd(engine, *cmd, desc, &default_desc);
1460 		if (!desc) {
1461 			DRM_DEBUG("CMD: Unrecognized command: 0x%08X\n", *cmd);
1462 			ret = -EINVAL;
1463 			break;
1464 		}
1465 
1466 		if (desc->flags & CMD_DESC_FIXED)
1467 			length = desc->length.fixed;
1468 		else
1469 			length = (*cmd & desc->length.mask) + LENGTH_BIAS;
1470 
1471 		if ((batch_end - cmd) < length) {
1472 			DRM_DEBUG("CMD: Command length exceeds batch length: 0x%08X length=%u batchlen=%td\n",
1473 				  *cmd,
1474 				  length,
1475 				  batch_end - cmd);
1476 			ret = -EINVAL;
1477 			break;
1478 		}
1479 
1480 		if (!check_cmd(engine, desc, cmd, length)) {
1481 			ret = -EACCES;
1482 			break;
1483 		}
1484 
1485 		if (desc->cmd.value == MI_BATCH_BUFFER_START) {
1486 			ret = check_bbstart(cmd, offset, length, batch_length,
1487 					    batch_addr, shadow_addr,
1488 					    jump_whitelist);
1489 			break;
1490 		}
1491 
1492 		if (!IS_ERR_OR_NULL(jump_whitelist))
1493 			__set_bit(offset, jump_whitelist);
1494 
1495 		cmd += length;
1496 		offset += length;
1497 		if  (cmd >= batch_end) {
1498 			DRM_DEBUG("CMD: Got to the end of the buffer w/o a BBE cmd!\n");
1499 			ret = -EINVAL;
1500 			break;
1501 		}
1502 	} while (1);
1503 
1504 	if (trampoline) {
1505 		/*
1506 		 * With the trampoline, the shadow is executed twice.
1507 		 *
1508 		 *   1 - starting at offset 0, in privileged mode
1509 		 *   2 - starting at offset batch_len, as non-privileged
1510 		 *
1511 		 * Only if the batch is valid and safe to execute, do we
1512 		 * allow the first privileged execution to proceed. If not,
1513 		 * we terminate the first batch and use the second batchbuffer
1514 		 * entry to chain to the original unsafe non-privileged batch,
1515 		 * leaving it to the HW to validate.
1516 		 */
1517 		*batch_end = MI_BATCH_BUFFER_END;
1518 
1519 		if (ret) {
1520 			/* Batch unsafe to execute with privileges, cancel! */
1521 			cmd = page_mask_bits(shadow->obj->mm.mapping);
1522 			*cmd = MI_BATCH_BUFFER_END;
1523 
1524 			/* If batch is unsafe but valid, jump to the original */
1525 			if (ret == -EACCES) {
1526 				unsigned int flags;
1527 
1528 				flags = MI_BATCH_NON_SECURE_I965;
1529 				if (IS_HASWELL(engine->i915))
1530 					flags = MI_BATCH_NON_SECURE_HSW;
1531 
1532 				GEM_BUG_ON(!IS_GEN_RANGE(engine->i915, 6, 7));
1533 				__gen6_emit_bb_start(batch_end,
1534 						     batch_addr,
1535 						     flags);
1536 
1537 				ret = 0; /* allow execution */
1538 			}
1539 		}
1540 
1541 		if (shadow_needs_clflush(shadow->obj))
1542 			drm_clflush_virt_range(batch_end, 8);
1543 	}
1544 
1545 	if (shadow_needs_clflush(shadow->obj)) {
1546 		void *ptr = page_mask_bits(shadow->obj->mm.mapping);
1547 
1548 		drm_clflush_virt_range(ptr, (void *)(cmd + 1) - ptr);
1549 	}
1550 
1551 	if (!IS_ERR_OR_NULL(jump_whitelist))
1552 		kfree(jump_whitelist);
1553 	i915_gem_object_unpin_map(shadow->obj);
1554 	return ret;
1555 }
1556 
1557 /**
1558  * i915_cmd_parser_get_version() - get the cmd parser version number
1559  * @dev_priv: i915 device private
1560  *
1561  * The cmd parser maintains a simple increasing integer version number suitable
1562  * for passing to userspace clients to determine what operations are permitted.
1563  *
1564  * Return: the current version number of the cmd parser
1565  */
i915_cmd_parser_get_version(struct drm_i915_private * dev_priv)1566 int i915_cmd_parser_get_version(struct drm_i915_private *dev_priv)
1567 {
1568 	struct intel_engine_cs *engine;
1569 	bool active = false;
1570 
1571 	/* If the command parser is not enabled, report 0 - unsupported */
1572 	for_each_uabi_engine(engine, dev_priv) {
1573 		if (intel_engine_using_cmd_parser(engine)) {
1574 			active = true;
1575 			break;
1576 		}
1577 	}
1578 	if (!active)
1579 		return 0;
1580 
1581 	/*
1582 	 * Command parser version history
1583 	 *
1584 	 * 1. Initial version. Checks batches and reports violations, but leaves
1585 	 *    hardware parsing enabled (so does not allow new use cases).
1586 	 * 2. Allow access to the MI_PREDICATE_SRC0 and
1587 	 *    MI_PREDICATE_SRC1 registers.
1588 	 * 3. Allow access to the GPGPU_THREADS_DISPATCHED register.
1589 	 * 4. L3 atomic chicken bits of HSW_SCRATCH1 and HSW_ROW_CHICKEN3.
1590 	 * 5. GPGPU dispatch compute indirect registers.
1591 	 * 6. TIMESTAMP register and Haswell CS GPR registers
1592 	 * 7. Allow MI_LOAD_REGISTER_REG between whitelisted registers.
1593 	 * 8. Don't report cmd_check() failures as EINVAL errors to userspace;
1594 	 *    rely on the HW to NOOP disallowed commands as it would without
1595 	 *    the parser enabled.
1596 	 * 9. Don't whitelist or handle oacontrol specially, as ownership
1597 	 *    for oacontrol state is moving to i915-perf.
1598 	 * 10. Support for Gen9 BCS Parsing
1599 	 */
1600 	return 10;
1601 }
1602