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 
30 #include "i915_drv.h"
31 #include "i915_memcpy.h"
32 
33 /**
34  * DOC: batch buffer command parser
35  *
36  * Motivation:
37  * Certain OpenGL features (e.g. transform feedback, performance monitoring)
38  * require userspace code to submit batches containing commands such as
39  * MI_LOAD_REGISTER_IMM to access various registers. Unfortunately, some
40  * generations of the hardware will noop these commands in "unsecure" batches
41  * (which includes all userspace batches submitted via i915) even though the
42  * commands may be safe and represent the intended programming model of the
43  * device.
44  *
45  * The software command parser is similar in operation to the command parsing
46  * done in hardware for unsecure batches. However, the software parser allows
47  * some operations that would be noop'd by hardware, if the parser determines
48  * the operation is safe, and submits the batch as "secure" to prevent hardware
49  * parsing.
50  *
51  * Threats:
52  * At a high level, the hardware (and software) checks attempt to prevent
53  * granting userspace undue privileges. There are three categories of privilege.
54  *
55  * First, commands which are explicitly defined as privileged or which should
56  * only be used by the kernel driver. The parser rejects such commands
57  *
58  * Second, commands which access registers. To support correct/enhanced
59  * userspace functionality, particularly certain OpenGL extensions, the parser
60  * provides a whitelist of registers which userspace may safely access
61  *
62  * Third, commands which access privileged memory (i.e. GGTT, HWS page, etc).
63  * The parser always rejects such commands.
64  *
65  * The majority of the problematic commands fall in the MI_* range, with only a
66  * few specific commands on each engine (e.g. PIPE_CONTROL and MI_FLUSH_DW).
67  *
68  * Implementation:
69  * Each engine maintains tables of commands and registers which the parser
70  * uses in scanning batch buffers submitted to that engine.
71  *
72  * Since the set of commands that the parser must check for is significantly
73  * smaller than the number of commands supported, the parser tables contain only
74  * those commands required by the parser. This generally works because command
75  * opcode ranges have standard command length encodings. So for commands that
76  * the parser does not need to check, it can easily skip them. This is
77  * implemented via a per-engine length decoding vfunc.
78  *
79  * Unfortunately, there are a number of commands that do not follow the standard
80  * length encoding for their opcode range, primarily amongst the MI_* commands.
81  * To handle this, the parser provides a way to define explicit "skip" entries
82  * in the per-engine command tables.
83  *
84  * Other command table entries map fairly directly to high level categories
85  * mentioned above: rejected, register whitelist. The parser implements a number
86  * of checks, including the privileged memory checks, via a general bitmasking
87  * mechanism.
88  */
89 
90 /*
91  * A command that requires special handling by the command parser.
92  */
93 struct drm_i915_cmd_descriptor {
94 	/*
95 	 * Flags describing how the command parser processes the command.
96 	 *
97 	 * CMD_DESC_FIXED: The command has a fixed length if this is set,
98 	 *                 a length mask if not set
99 	 * CMD_DESC_SKIP: The command is allowed but does not follow the
100 	 *                standard length encoding for the opcode range in
101 	 *                which it falls
102 	 * CMD_DESC_REJECT: The command is never allowed
103 	 * CMD_DESC_REGISTER: The command should be checked against the
104 	 *                    register whitelist for the appropriate ring
105 	 */
106 	u32 flags;
107 #define CMD_DESC_FIXED    (1<<0)
108 #define CMD_DESC_SKIP     (1<<1)
109 #define CMD_DESC_REJECT   (1<<2)
110 #define CMD_DESC_REGISTER (1<<3)
111 #define CMD_DESC_BITMASK  (1<<4)
112 
113 	/*
114 	 * The command's unique identification bits and the bitmask to get them.
115 	 * This isn't strictly the opcode field as defined in the spec and may
116 	 * also include type, subtype, and/or subop fields.
117 	 */
118 	struct {
119 		u32 value;
120 		u32 mask;
121 	} cmd;
122 
123 	/*
124 	 * The command's length. The command is either fixed length (i.e. does
125 	 * not include a length field) or has a length field mask. The flag
126 	 * CMD_DESC_FIXED indicates a fixed length. Otherwise, the command has
127 	 * a length mask. All command entries in a command table must include
128 	 * length information.
129 	 */
130 	union {
131 		u32 fixed;
132 		u32 mask;
133 	} length;
134 
135 	/*
136 	 * Describes where to find a register address in the command to check
137 	 * against the ring's register whitelist. Only valid if flags has the
138 	 * CMD_DESC_REGISTER bit set.
139 	 *
140 	 * A non-zero step value implies that the command may access multiple
141 	 * registers in sequence (e.g. LRI), in that case step gives the
142 	 * distance in dwords between individual offset fields.
143 	 */
144 	struct {
145 		u32 offset;
146 		u32 mask;
147 		u32 step;
148 	} reg;
149 
150 #define MAX_CMD_DESC_BITMASKS 3
151 	/*
152 	 * Describes command checks where a particular dword is masked and
153 	 * compared against an expected value. If the command does not match
154 	 * the expected value, the parser rejects it. Only valid if flags has
155 	 * the CMD_DESC_BITMASK bit set. Only entries where mask is non-zero
156 	 * are valid.
157 	 *
158 	 * If the check specifies a non-zero condition_mask then the parser
159 	 * only performs the check when the bits specified by condition_mask
160 	 * are non-zero.
161 	 */
162 	struct {
163 		u32 offset;
164 		u32 mask;
165 		u32 expected;
166 		u32 condition_offset;
167 		u32 condition_mask;
168 	} bits[MAX_CMD_DESC_BITMASKS];
169 };
170 
171 /*
172  * A table of commands requiring special handling by the command parser.
173  *
174  * Each engine has an array of tables. Each table consists of an array of
175  * command descriptors, which must be sorted with command opcodes in
176  * ascending order.
177  */
178 struct drm_i915_cmd_table {
179 	const struct drm_i915_cmd_descriptor *table;
180 	int count;
181 };
182 
183 #define STD_MI_OPCODE_SHIFT  (32 - 9)
184 #define STD_3D_OPCODE_SHIFT  (32 - 16)
185 #define STD_2D_OPCODE_SHIFT  (32 - 10)
186 #define STD_MFX_OPCODE_SHIFT (32 - 16)
187 #define MIN_OPCODE_SHIFT 16
188 
189 #define CMD(op, opm, f, lm, fl, ...)				\
190 	{							\
191 		.flags = (fl) | ((f) ? CMD_DESC_FIXED : 0),	\
192 		.cmd = { (op & ~0u << (opm)), ~0u << (opm) },	\
193 		.length = { (lm) },				\
194 		__VA_ARGS__					\
195 	}
196 
197 /* Convenience macros to compress the tables */
198 #define SMI STD_MI_OPCODE_SHIFT
199 #define S3D STD_3D_OPCODE_SHIFT
200 #define S2D STD_2D_OPCODE_SHIFT
201 #define SMFX STD_MFX_OPCODE_SHIFT
202 #define F true
203 #define S CMD_DESC_SKIP
204 #define R CMD_DESC_REJECT
205 #define W CMD_DESC_REGISTER
206 #define B CMD_DESC_BITMASK
207 
208 /*            Command                          Mask   Fixed Len   Action
209 	      ---------------------------------------------------------- */
210 static const struct drm_i915_cmd_descriptor gen7_common_cmds[] = {
211 	CMD(  MI_NOOP,                          SMI,    F,  1,      S  ),
212 	CMD(  MI_USER_INTERRUPT,                SMI,    F,  1,      R  ),
213 	CMD(  MI_WAIT_FOR_EVENT,                SMI,    F,  1,      R  ),
214 	CMD(  MI_ARB_CHECK,                     SMI,    F,  1,      S  ),
215 	CMD(  MI_REPORT_HEAD,                   SMI,    F,  1,      S  ),
216 	CMD(  MI_SUSPEND_FLUSH,                 SMI,    F,  1,      S  ),
217 	CMD(  MI_SEMAPHORE_MBOX,                SMI,   !F,  0xFF,   R  ),
218 	CMD(  MI_STORE_DWORD_INDEX,             SMI,   !F,  0xFF,   R  ),
219 	CMD(  MI_LOAD_REGISTER_IMM(1),          SMI,   !F,  0xFF,   W,
220 	      .reg = { .offset = 1, .mask = 0x007FFFFC, .step = 2 }    ),
221 	CMD(  MI_STORE_REGISTER_MEM,            SMI,    F,  3,     W | B,
222 	      .reg = { .offset = 1, .mask = 0x007FFFFC },
223 	      .bits = {{
224 			.offset = 0,
225 			.mask = MI_GLOBAL_GTT,
226 			.expected = 0,
227 	      }},						       ),
228 	CMD(  MI_LOAD_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 	/*
236 	 * MI_BATCH_BUFFER_START requires some special handling. It's not
237 	 * really a 'skip' action but it doesn't seem like it's worth adding
238 	 * a new action. See intel_engine_cmd_parser().
239 	 */
240 	CMD(  MI_BATCH_BUFFER_START,            SMI,   !F,  0xFF,   S  ),
241 };
242 
243 static const struct drm_i915_cmd_descriptor gen7_render_cmds[] = {
244 	CMD(  MI_FLUSH,                         SMI,    F,  1,      S  ),
245 	CMD(  MI_ARB_ON_OFF,                    SMI,    F,  1,      R  ),
246 	CMD(  MI_PREDICATE,                     SMI,    F,  1,      S  ),
247 	CMD(  MI_TOPOLOGY_FILTER,               SMI,    F,  1,      S  ),
248 	CMD(  MI_SET_APPID,                     SMI,    F,  1,      S  ),
249 	CMD(  MI_DISPLAY_FLIP,                  SMI,   !F,  0xFF,   R  ),
250 	CMD(  MI_SET_CONTEXT,                   SMI,   !F,  0xFF,   R  ),
251 	CMD(  MI_URB_CLEAR,                     SMI,   !F,  0xFF,   S  ),
252 	CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0x3F,   B,
253 	      .bits = {{
254 			.offset = 0,
255 			.mask = MI_GLOBAL_GTT,
256 			.expected = 0,
257 	      }},						       ),
258 	CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0xFF,   R  ),
259 	CMD(  MI_CLFLUSH,                       SMI,   !F,  0x3FF,  B,
260 	      .bits = {{
261 			.offset = 0,
262 			.mask = MI_GLOBAL_GTT,
263 			.expected = 0,
264 	      }},						       ),
265 	CMD(  MI_REPORT_PERF_COUNT,             SMI,   !F,  0x3F,   B,
266 	      .bits = {{
267 			.offset = 1,
268 			.mask = MI_REPORT_PERF_COUNT_GGTT,
269 			.expected = 0,
270 	      }},						       ),
271 	CMD(  MI_CONDITIONAL_BATCH_BUFFER_END,  SMI,   !F,  0xFF,   B,
272 	      .bits = {{
273 			.offset = 0,
274 			.mask = MI_GLOBAL_GTT,
275 			.expected = 0,
276 	      }},						       ),
277 	CMD(  GFX_OP_3DSTATE_VF_STATISTICS,     S3D,    F,  1,      S  ),
278 	CMD(  PIPELINE_SELECT,                  S3D,    F,  1,      S  ),
279 	CMD(  MEDIA_VFE_STATE,			S3D,   !F,  0xFFFF, B,
280 	      .bits = {{
281 			.offset = 2,
282 			.mask = MEDIA_VFE_STATE_MMIO_ACCESS_MASK,
283 			.expected = 0,
284 	      }},						       ),
285 	CMD(  GPGPU_OBJECT,                     S3D,   !F,  0xFF,   S  ),
286 	CMD(  GPGPU_WALKER,                     S3D,   !F,  0xFF,   S  ),
287 	CMD(  GFX_OP_3DSTATE_SO_DECL_LIST,      S3D,   !F,  0x1FF,  S  ),
288 	CMD(  GFX_OP_PIPE_CONTROL(5),           S3D,   !F,  0xFF,   B,
289 	      .bits = {{
290 			.offset = 1,
291 			.mask = (PIPE_CONTROL_MMIO_WRITE | PIPE_CONTROL_NOTIFY),
292 			.expected = 0,
293 	      },
294 	      {
295 			.offset = 1,
296 		        .mask = (PIPE_CONTROL_GLOBAL_GTT_IVB |
297 				 PIPE_CONTROL_STORE_DATA_INDEX),
298 			.expected = 0,
299 			.condition_offset = 1,
300 			.condition_mask = PIPE_CONTROL_POST_SYNC_OP_MASK,
301 	      }},						       ),
302 };
303 
304 static const struct drm_i915_cmd_descriptor hsw_render_cmds[] = {
305 	CMD(  MI_SET_PREDICATE,                 SMI,    F,  1,      S  ),
306 	CMD(  MI_RS_CONTROL,                    SMI,    F,  1,      S  ),
307 	CMD(  MI_URB_ATOMIC_ALLOC,              SMI,    F,  1,      S  ),
308 	CMD(  MI_SET_APPID,                     SMI,    F,  1,      S  ),
309 	CMD(  MI_RS_CONTEXT,                    SMI,    F,  1,      S  ),
310 	CMD(  MI_LOAD_SCAN_LINES_INCL,          SMI,   !F,  0x3F,   R  ),
311 	CMD(  MI_LOAD_SCAN_LINES_EXCL,          SMI,   !F,  0x3F,   R  ),
312 	CMD(  MI_LOAD_REGISTER_REG,             SMI,   !F,  0xFF,   W,
313 	      .reg = { .offset = 1, .mask = 0x007FFFFC, .step = 1 }    ),
314 	CMD(  MI_RS_STORE_DATA_IMM,             SMI,   !F,  0xFF,   S  ),
315 	CMD(  MI_LOAD_URB_MEM,                  SMI,   !F,  0xFF,   S  ),
316 	CMD(  MI_STORE_URB_MEM,                 SMI,   !F,  0xFF,   S  ),
317 	CMD(  GFX_OP_3DSTATE_DX9_CONSTANTF_VS,  S3D,   !F,  0x7FF,  S  ),
318 	CMD(  GFX_OP_3DSTATE_DX9_CONSTANTF_PS,  S3D,   !F,  0x7FF,  S  ),
319 
320 	CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_VS,  S3D,   !F,  0x1FF,  S  ),
321 	CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_GS,  S3D,   !F,  0x1FF,  S  ),
322 	CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_HS,  S3D,   !F,  0x1FF,  S  ),
323 	CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_DS,  S3D,   !F,  0x1FF,  S  ),
324 	CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_PS,  S3D,   !F,  0x1FF,  S  ),
325 };
326 
327 static const struct drm_i915_cmd_descriptor gen7_video_cmds[] = {
328 	CMD(  MI_ARB_ON_OFF,                    SMI,    F,  1,      R  ),
329 	CMD(  MI_SET_APPID,                     SMI,    F,  1,      S  ),
330 	CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0xFF,   B,
331 	      .bits = {{
332 			.offset = 0,
333 			.mask = MI_GLOBAL_GTT,
334 			.expected = 0,
335 	      }},						       ),
336 	CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0x3F,   R  ),
337 	CMD(  MI_FLUSH_DW,                      SMI,   !F,  0x3F,   B,
338 	      .bits = {{
339 			.offset = 0,
340 			.mask = MI_FLUSH_DW_NOTIFY,
341 			.expected = 0,
342 	      },
343 	      {
344 			.offset = 1,
345 			.mask = MI_FLUSH_DW_USE_GTT,
346 			.expected = 0,
347 			.condition_offset = 0,
348 			.condition_mask = MI_FLUSH_DW_OP_MASK,
349 	      },
350 	      {
351 			.offset = 0,
352 			.mask = MI_FLUSH_DW_STORE_INDEX,
353 			.expected = 0,
354 			.condition_offset = 0,
355 			.condition_mask = MI_FLUSH_DW_OP_MASK,
356 	      }},						       ),
357 	CMD(  MI_CONDITIONAL_BATCH_BUFFER_END,  SMI,   !F,  0xFF,   B,
358 	      .bits = {{
359 			.offset = 0,
360 			.mask = MI_GLOBAL_GTT,
361 			.expected = 0,
362 	      }},						       ),
363 	/*
364 	 * MFX_WAIT doesn't fit the way we handle length for most commands.
365 	 * It has a length field but it uses a non-standard length bias.
366 	 * It is always 1 dword though, so just treat it as fixed length.
367 	 */
368 	CMD(  MFX_WAIT,                         SMFX,   F,  1,      S  ),
369 };
370 
371 static const struct drm_i915_cmd_descriptor gen7_vecs_cmds[] = {
372 	CMD(  MI_ARB_ON_OFF,                    SMI,    F,  1,      R  ),
373 	CMD(  MI_SET_APPID,                     SMI,    F,  1,      S  ),
374 	CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0xFF,   B,
375 	      .bits = {{
376 			.offset = 0,
377 			.mask = MI_GLOBAL_GTT,
378 			.expected = 0,
379 	      }},						       ),
380 	CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0x3F,   R  ),
381 	CMD(  MI_FLUSH_DW,                      SMI,   !F,  0x3F,   B,
382 	      .bits = {{
383 			.offset = 0,
384 			.mask = MI_FLUSH_DW_NOTIFY,
385 			.expected = 0,
386 	      },
387 	      {
388 			.offset = 1,
389 			.mask = MI_FLUSH_DW_USE_GTT,
390 			.expected = 0,
391 			.condition_offset = 0,
392 			.condition_mask = MI_FLUSH_DW_OP_MASK,
393 	      },
394 	      {
395 			.offset = 0,
396 			.mask = MI_FLUSH_DW_STORE_INDEX,
397 			.expected = 0,
398 			.condition_offset = 0,
399 			.condition_mask = MI_FLUSH_DW_OP_MASK,
400 	      }},						       ),
401 	CMD(  MI_CONDITIONAL_BATCH_BUFFER_END,  SMI,   !F,  0xFF,   B,
402 	      .bits = {{
403 			.offset = 0,
404 			.mask = MI_GLOBAL_GTT,
405 			.expected = 0,
406 	      }},						       ),
407 };
408 
409 static const struct drm_i915_cmd_descriptor gen7_blt_cmds[] = {
410 	CMD(  MI_DISPLAY_FLIP,                  SMI,   !F,  0xFF,   R  ),
411 	CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0x3FF,  B,
412 	      .bits = {{
413 			.offset = 0,
414 			.mask = MI_GLOBAL_GTT,
415 			.expected = 0,
416 	      }},						       ),
417 	CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0x3F,   R  ),
418 	CMD(  MI_FLUSH_DW,                      SMI,   !F,  0x3F,   B,
419 	      .bits = {{
420 			.offset = 0,
421 			.mask = MI_FLUSH_DW_NOTIFY,
422 			.expected = 0,
423 	      },
424 	      {
425 			.offset = 1,
426 			.mask = MI_FLUSH_DW_USE_GTT,
427 			.expected = 0,
428 			.condition_offset = 0,
429 			.condition_mask = MI_FLUSH_DW_OP_MASK,
430 	      },
431 	      {
432 			.offset = 0,
433 			.mask = MI_FLUSH_DW_STORE_INDEX,
434 			.expected = 0,
435 			.condition_offset = 0,
436 			.condition_mask = MI_FLUSH_DW_OP_MASK,
437 	      }},						       ),
438 	CMD(  COLOR_BLT,                        S2D,   !F,  0x3F,   S  ),
439 	CMD(  SRC_COPY_BLT,                     S2D,   !F,  0x3F,   S  ),
440 };
441 
442 static const struct drm_i915_cmd_descriptor hsw_blt_cmds[] = {
443 	CMD(  MI_LOAD_SCAN_LINES_INCL,          SMI,   !F,  0x3F,   R  ),
444 	CMD(  MI_LOAD_SCAN_LINES_EXCL,          SMI,   !F,  0x3F,   R  ),
445 };
446 
447 /*
448  * For Gen9 we can still rely on the h/w to enforce cmd security, and only
449  * need to re-enforce the register access checks. We therefore only need to
450  * teach the cmdparser how to find the end of each command, and identify
451  * register accesses. The table doesn't need to reject any commands, and so
452  * the only commands listed here are:
453  *   1) Those that touch registers
454  *   2) Those that do not have the default 8-bit length
455  *
456  * Note that the default MI length mask chosen for this table is 0xFF, not
457  * the 0x3F used on older devices. This is because the vast majority of MI
458  * cmds on Gen9 use a standard 8-bit Length field.
459  * All the Gen9 blitter instructions are standard 0xFF length mask, and
460  * none allow access to non-general registers, so in fact no BLT cmds are
461  * included in the table at all.
462  *
463  */
464 static const struct drm_i915_cmd_descriptor gen9_blt_cmds[] = {
465 	CMD(  MI_NOOP,                          SMI,    F,  1,      S  ),
466 	CMD(  MI_USER_INTERRUPT,                SMI,    F,  1,      S  ),
467 	CMD(  MI_WAIT_FOR_EVENT,                SMI,    F,  1,      S  ),
468 	CMD(  MI_FLUSH,                         SMI,    F,  1,      S  ),
469 	CMD(  MI_ARB_CHECK,                     SMI,    F,  1,      S  ),
470 	CMD(  MI_REPORT_HEAD,                   SMI,    F,  1,      S  ),
471 	CMD(  MI_ARB_ON_OFF,                    SMI,    F,  1,      S  ),
472 	CMD(  MI_SUSPEND_FLUSH,                 SMI,    F,  1,      S  ),
473 	CMD(  MI_LOAD_SCAN_LINES_INCL,          SMI,   !F,  0x3F,   S  ),
474 	CMD(  MI_LOAD_SCAN_LINES_EXCL,          SMI,   !F,  0x3F,   S  ),
475 	CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0x3FF,  S  ),
476 	CMD(  MI_LOAD_REGISTER_IMM(1),          SMI,   !F,  0xFF,   W,
477 	      .reg = { .offset = 1, .mask = 0x007FFFFC, .step = 2 }    ),
478 	CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0x3FF,  S  ),
479 	CMD(  MI_STORE_REGISTER_MEM_GEN8,       SMI,    F,  4,      W,
480 	      .reg = { .offset = 1, .mask = 0x007FFFFC }               ),
481 	CMD(  MI_FLUSH_DW,                      SMI,   !F,  0x3F,   S  ),
482 	CMD(  MI_LOAD_REGISTER_MEM_GEN8,        SMI,    F,  4,      W,
483 	      .reg = { .offset = 1, .mask = 0x007FFFFC }               ),
484 	CMD(  MI_LOAD_REGISTER_REG,             SMI,    !F,  0xFF,  W,
485 	      .reg = { .offset = 1, .mask = 0x007FFFFC, .step = 1 }    ),
486 
487 	/*
488 	 * We allow BB_START but apply further checks. We just sanitize the
489 	 * basic fields here.
490 	 */
491 #define MI_BB_START_OPERAND_MASK   GENMASK(SMI-1, 0)
492 #define MI_BB_START_OPERAND_EXPECT (MI_BATCH_PPGTT_HSW | 1)
493 	CMD(  MI_BATCH_BUFFER_START_GEN8,       SMI,    !F,  0xFF,  B,
494 	      .bits = {{
495 			.offset = 0,
496 			.mask = MI_BB_START_OPERAND_MASK,
497 			.expected = MI_BB_START_OPERAND_EXPECT,
498 	      }},						       ),
499 };
500 
501 static const struct drm_i915_cmd_descriptor noop_desc =
502 	CMD(MI_NOOP, SMI, F, 1, S);
503 
504 #undef CMD
505 #undef SMI
506 #undef S3D
507 #undef S2D
508 #undef SMFX
509 #undef F
510 #undef S
511 #undef R
512 #undef W
513 #undef B
514 
515 static const struct drm_i915_cmd_table gen7_render_cmd_table[] = {
516 	{ gen7_common_cmds, ARRAY_SIZE(gen7_common_cmds) },
517 	{ gen7_render_cmds, ARRAY_SIZE(gen7_render_cmds) },
518 };
519 
520 static const struct drm_i915_cmd_table hsw_render_ring_cmd_table[] = {
521 	{ gen7_common_cmds, ARRAY_SIZE(gen7_common_cmds) },
522 	{ gen7_render_cmds, ARRAY_SIZE(gen7_render_cmds) },
523 	{ hsw_render_cmds, ARRAY_SIZE(hsw_render_cmds) },
524 };
525 
526 static const struct drm_i915_cmd_table gen7_video_cmd_table[] = {
527 	{ gen7_common_cmds, ARRAY_SIZE(gen7_common_cmds) },
528 	{ gen7_video_cmds, ARRAY_SIZE(gen7_video_cmds) },
529 };
530 
531 static const struct drm_i915_cmd_table hsw_vebox_cmd_table[] = {
532 	{ gen7_common_cmds, ARRAY_SIZE(gen7_common_cmds) },
533 	{ gen7_vecs_cmds, ARRAY_SIZE(gen7_vecs_cmds) },
534 };
535 
536 static const struct drm_i915_cmd_table gen7_blt_cmd_table[] = {
537 	{ gen7_common_cmds, ARRAY_SIZE(gen7_common_cmds) },
538 	{ gen7_blt_cmds, ARRAY_SIZE(gen7_blt_cmds) },
539 };
540 
541 static const struct drm_i915_cmd_table hsw_blt_ring_cmd_table[] = {
542 	{ gen7_common_cmds, ARRAY_SIZE(gen7_common_cmds) },
543 	{ gen7_blt_cmds, ARRAY_SIZE(gen7_blt_cmds) },
544 	{ hsw_blt_cmds, ARRAY_SIZE(hsw_blt_cmds) },
545 };
546 
547 static const struct drm_i915_cmd_table gen9_blt_cmd_table[] = {
548 	{ gen9_blt_cmds, ARRAY_SIZE(gen9_blt_cmds) },
549 };
550 
551 
552 /*
553  * Register whitelists, sorted by increasing register offset.
554  */
555 
556 /*
557  * An individual whitelist entry granting access to register addr.  If
558  * mask is non-zero the argument of immediate register writes will be
559  * AND-ed with mask, and the command will be rejected if the result
560  * doesn't match value.
561  *
562  * Registers with non-zero mask are only allowed to be written using
563  * LRI.
564  */
565 struct drm_i915_reg_descriptor {
566 	i915_reg_t addr;
567 	u32 mask;
568 	u32 value;
569 };
570 
571 /* Convenience macro for adding 32-bit registers. */
572 #define REG32(_reg, ...) \
573 	{ .addr = (_reg), __VA_ARGS__ }
574 
575 /*
576  * Convenience macro for adding 64-bit registers.
577  *
578  * Some registers that userspace accesses are 64 bits. The register
579  * access commands only allow 32-bit accesses. Hence, we have to include
580  * entries for both halves of the 64-bit registers.
581  */
582 #define REG64(_reg) \
583 	{ .addr = _reg }, \
584 	{ .addr = _reg ## _UDW }
585 
586 #define REG64_IDX(_reg, idx) \
587 	{ .addr = _reg(idx) }, \
588 	{ .addr = _reg ## _UDW(idx) }
589 
590 static const struct drm_i915_reg_descriptor gen7_render_regs[] = {
591 	REG64(GPGPU_THREADS_DISPATCHED),
592 	REG64(HS_INVOCATION_COUNT),
593 	REG64(DS_INVOCATION_COUNT),
594 	REG64(IA_VERTICES_COUNT),
595 	REG64(IA_PRIMITIVES_COUNT),
596 	REG64(VS_INVOCATION_COUNT),
597 	REG64(GS_INVOCATION_COUNT),
598 	REG64(GS_PRIMITIVES_COUNT),
599 	REG64(CL_INVOCATION_COUNT),
600 	REG64(CL_PRIMITIVES_COUNT),
601 	REG64(PS_INVOCATION_COUNT),
602 	REG64(PS_DEPTH_COUNT),
603 	REG64_IDX(RING_TIMESTAMP, RENDER_RING_BASE),
604 	REG64(MI_PREDICATE_SRC0),
605 	REG64(MI_PREDICATE_SRC1),
606 	REG32(GEN7_3DPRIM_END_OFFSET),
607 	REG32(GEN7_3DPRIM_START_VERTEX),
608 	REG32(GEN7_3DPRIM_VERTEX_COUNT),
609 	REG32(GEN7_3DPRIM_INSTANCE_COUNT),
610 	REG32(GEN7_3DPRIM_START_INSTANCE),
611 	REG32(GEN7_3DPRIM_BASE_VERTEX),
612 	REG32(GEN7_GPGPU_DISPATCHDIMX),
613 	REG32(GEN7_GPGPU_DISPATCHDIMY),
614 	REG32(GEN7_GPGPU_DISPATCHDIMZ),
615 	REG64_IDX(RING_TIMESTAMP, BSD_RING_BASE),
616 	REG64_IDX(GEN7_SO_NUM_PRIMS_WRITTEN, 0),
617 	REG64_IDX(GEN7_SO_NUM_PRIMS_WRITTEN, 1),
618 	REG64_IDX(GEN7_SO_NUM_PRIMS_WRITTEN, 2),
619 	REG64_IDX(GEN7_SO_NUM_PRIMS_WRITTEN, 3),
620 	REG64_IDX(GEN7_SO_PRIM_STORAGE_NEEDED, 0),
621 	REG64_IDX(GEN7_SO_PRIM_STORAGE_NEEDED, 1),
622 	REG64_IDX(GEN7_SO_PRIM_STORAGE_NEEDED, 2),
623 	REG64_IDX(GEN7_SO_PRIM_STORAGE_NEEDED, 3),
624 	REG32(GEN7_SO_WRITE_OFFSET(0)),
625 	REG32(GEN7_SO_WRITE_OFFSET(1)),
626 	REG32(GEN7_SO_WRITE_OFFSET(2)),
627 	REG32(GEN7_SO_WRITE_OFFSET(3)),
628 	REG32(GEN7_L3SQCREG1),
629 	REG32(GEN7_L3CNTLREG2),
630 	REG32(GEN7_L3CNTLREG3),
631 	REG64_IDX(RING_TIMESTAMP, BLT_RING_BASE),
632 };
633 
634 static const struct drm_i915_reg_descriptor hsw_render_regs[] = {
635 	REG64_IDX(HSW_CS_GPR, 0),
636 	REG64_IDX(HSW_CS_GPR, 1),
637 	REG64_IDX(HSW_CS_GPR, 2),
638 	REG64_IDX(HSW_CS_GPR, 3),
639 	REG64_IDX(HSW_CS_GPR, 4),
640 	REG64_IDX(HSW_CS_GPR, 5),
641 	REG64_IDX(HSW_CS_GPR, 6),
642 	REG64_IDX(HSW_CS_GPR, 7),
643 	REG64_IDX(HSW_CS_GPR, 8),
644 	REG64_IDX(HSW_CS_GPR, 9),
645 	REG64_IDX(HSW_CS_GPR, 10),
646 	REG64_IDX(HSW_CS_GPR, 11),
647 	REG64_IDX(HSW_CS_GPR, 12),
648 	REG64_IDX(HSW_CS_GPR, 13),
649 	REG64_IDX(HSW_CS_GPR, 14),
650 	REG64_IDX(HSW_CS_GPR, 15),
651 	REG32(HSW_SCRATCH1,
652 	      .mask = ~HSW_SCRATCH1_L3_DATA_ATOMICS_DISABLE,
653 	      .value = 0),
654 	REG32(HSW_ROW_CHICKEN3,
655 	      .mask = ~(HSW_ROW_CHICKEN3_L3_GLOBAL_ATOMICS_DISABLE << 16 |
656                         HSW_ROW_CHICKEN3_L3_GLOBAL_ATOMICS_DISABLE),
657 	      .value = 0),
658 };
659 
660 static const struct drm_i915_reg_descriptor gen7_blt_regs[] = {
661 	REG64_IDX(RING_TIMESTAMP, RENDER_RING_BASE),
662 	REG64_IDX(RING_TIMESTAMP, BSD_RING_BASE),
663 	REG32(BCS_SWCTRL),
664 	REG64_IDX(RING_TIMESTAMP, BLT_RING_BASE),
665 };
666 
667 static const struct drm_i915_reg_descriptor gen9_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 	REG64_IDX(BCS_GPR, 0),
673 	REG64_IDX(BCS_GPR, 1),
674 	REG64_IDX(BCS_GPR, 2),
675 	REG64_IDX(BCS_GPR, 3),
676 	REG64_IDX(BCS_GPR, 4),
677 	REG64_IDX(BCS_GPR, 5),
678 	REG64_IDX(BCS_GPR, 6),
679 	REG64_IDX(BCS_GPR, 7),
680 	REG64_IDX(BCS_GPR, 8),
681 	REG64_IDX(BCS_GPR, 9),
682 	REG64_IDX(BCS_GPR, 10),
683 	REG64_IDX(BCS_GPR, 11),
684 	REG64_IDX(BCS_GPR, 12),
685 	REG64_IDX(BCS_GPR, 13),
686 	REG64_IDX(BCS_GPR, 14),
687 	REG64_IDX(BCS_GPR, 15),
688 };
689 
690 #undef REG64
691 #undef REG32
692 
693 struct drm_i915_reg_table {
694 	const struct drm_i915_reg_descriptor *regs;
695 	int num_regs;
696 };
697 
698 static const struct drm_i915_reg_table ivb_render_reg_tables[] = {
699 	{ gen7_render_regs, ARRAY_SIZE(gen7_render_regs) },
700 };
701 
702 static const struct drm_i915_reg_table ivb_blt_reg_tables[] = {
703 	{ gen7_blt_regs, ARRAY_SIZE(gen7_blt_regs) },
704 };
705 
706 static const struct drm_i915_reg_table hsw_render_reg_tables[] = {
707 	{ gen7_render_regs, ARRAY_SIZE(gen7_render_regs) },
708 	{ hsw_render_regs, ARRAY_SIZE(hsw_render_regs) },
709 };
710 
711 static const struct drm_i915_reg_table hsw_blt_reg_tables[] = {
712 	{ gen7_blt_regs, ARRAY_SIZE(gen7_blt_regs) },
713 };
714 
715 static const struct drm_i915_reg_table gen9_blt_reg_tables[] = {
716 	{ gen9_blt_regs, ARRAY_SIZE(gen9_blt_regs) },
717 };
718 
719 static u32 gen7_render_get_cmd_length_mask(u32 cmd_header)
720 {
721 	u32 client = cmd_header >> INSTR_CLIENT_SHIFT;
722 	u32 subclient =
723 		(cmd_header & INSTR_SUBCLIENT_MASK) >> INSTR_SUBCLIENT_SHIFT;
724 
725 	if (client == INSTR_MI_CLIENT)
726 		return 0x3F;
727 	else if (client == INSTR_RC_CLIENT) {
728 		if (subclient == INSTR_MEDIA_SUBCLIENT)
729 			return 0xFFFF;
730 		else
731 			return 0xFF;
732 	}
733 
734 	DRM_DEBUG("CMD: Abnormal rcs cmd length! 0x%08X\n", cmd_header);
735 	return 0;
736 }
737 
738 static u32 gen7_bsd_get_cmd_length_mask(u32 cmd_header)
739 {
740 	u32 client = cmd_header >> INSTR_CLIENT_SHIFT;
741 	u32 subclient =
742 		(cmd_header & INSTR_SUBCLIENT_MASK) >> INSTR_SUBCLIENT_SHIFT;
743 	u32 op = (cmd_header & INSTR_26_TO_24_MASK) >> INSTR_26_TO_24_SHIFT;
744 
745 	if (client == INSTR_MI_CLIENT)
746 		return 0x3F;
747 	else if (client == INSTR_RC_CLIENT) {
748 		if (subclient == INSTR_MEDIA_SUBCLIENT) {
749 			if (op == 6)
750 				return 0xFFFF;
751 			else
752 				return 0xFFF;
753 		} else
754 			return 0xFF;
755 	}
756 
757 	DRM_DEBUG("CMD: Abnormal bsd cmd length! 0x%08X\n", cmd_header);
758 	return 0;
759 }
760 
761 static u32 gen7_blt_get_cmd_length_mask(u32 cmd_header)
762 {
763 	u32 client = cmd_header >> INSTR_CLIENT_SHIFT;
764 
765 	if (client == INSTR_MI_CLIENT)
766 		return 0x3F;
767 	else if (client == INSTR_BC_CLIENT)
768 		return 0xFF;
769 
770 	DRM_DEBUG("CMD: Abnormal blt cmd length! 0x%08X\n", cmd_header);
771 	return 0;
772 }
773 
774 static u32 gen9_blt_get_cmd_length_mask(u32 cmd_header)
775 {
776 	u32 client = cmd_header >> INSTR_CLIENT_SHIFT;
777 
778 	if (client == INSTR_MI_CLIENT || client == INSTR_BC_CLIENT)
779 		return 0xFF;
780 
781 	DRM_DEBUG("CMD: Abnormal blt cmd length! 0x%08X\n", cmd_header);
782 	return 0;
783 }
784 
785 static bool validate_cmds_sorted(const struct intel_engine_cs *engine,
786 				 const struct drm_i915_cmd_table *cmd_tables,
787 				 int cmd_table_count)
788 {
789 	int i;
790 	bool ret = true;
791 
792 	if (!cmd_tables || cmd_table_count == 0)
793 		return true;
794 
795 	for (i = 0; i < cmd_table_count; i++) {
796 		const struct drm_i915_cmd_table *table = &cmd_tables[i];
797 		u32 previous = 0;
798 		int j;
799 
800 		for (j = 0; j < table->count; j++) {
801 			const struct drm_i915_cmd_descriptor *desc =
802 				&table->table[j];
803 			u32 curr = desc->cmd.value & desc->cmd.mask;
804 
805 			if (curr < previous) {
806 				DRM_ERROR("CMD: %s [%d] command table not sorted: "
807 					  "table=%d entry=%d cmd=0x%08X prev=0x%08X\n",
808 					  engine->name, engine->id,
809 					  i, j, curr, previous);
810 				ret = false;
811 			}
812 
813 			previous = curr;
814 		}
815 	}
816 
817 	return ret;
818 }
819 
820 static bool check_sorted(const struct intel_engine_cs *engine,
821 			 const struct drm_i915_reg_descriptor *reg_table,
822 			 int reg_count)
823 {
824 	int i;
825 	u32 previous = 0;
826 	bool ret = true;
827 
828 	for (i = 0; i < reg_count; i++) {
829 		u32 curr = i915_mmio_reg_offset(reg_table[i].addr);
830 
831 		if (curr < previous) {
832 			DRM_ERROR("CMD: %s [%d] register table not sorted: "
833 				  "entry=%d reg=0x%08X prev=0x%08X\n",
834 				  engine->name, engine->id,
835 				  i, curr, previous);
836 			ret = false;
837 		}
838 
839 		previous = curr;
840 	}
841 
842 	return ret;
843 }
844 
845 static bool validate_regs_sorted(struct intel_engine_cs *engine)
846 {
847 	int i;
848 	const struct drm_i915_reg_table *table;
849 
850 	for (i = 0; i < engine->reg_table_count; i++) {
851 		table = &engine->reg_tables[i];
852 		if (!check_sorted(engine, table->regs, table->num_regs))
853 			return false;
854 	}
855 
856 	return true;
857 }
858 
859 struct cmd_node {
860 	const struct drm_i915_cmd_descriptor *desc;
861 	struct hlist_node node;
862 };
863 
864 /*
865  * Different command ranges have different numbers of bits for the opcode. For
866  * example, MI commands use bits 31:23 while 3D commands use bits 31:16. The
867  * problem is that, for example, MI commands use bits 22:16 for other fields
868  * such as GGTT vs PPGTT bits. If we include those bits in the mask then when
869  * we mask a command from a batch it could hash to the wrong bucket due to
870  * non-opcode bits being set. But if we don't include those bits, some 3D
871  * commands may hash to the same bucket due to not including opcode bits that
872  * make the command unique. For now, we will risk hashing to the same bucket.
873  */
874 static inline u32 cmd_header_key(u32 x)
875 {
876 	switch (x >> INSTR_CLIENT_SHIFT) {
877 	default:
878 	case INSTR_MI_CLIENT:
879 		return x >> STD_MI_OPCODE_SHIFT;
880 	case INSTR_RC_CLIENT:
881 		return x >> STD_3D_OPCODE_SHIFT;
882 	case INSTR_BC_CLIENT:
883 		return x >> STD_2D_OPCODE_SHIFT;
884 	}
885 }
886 
887 static int init_hash_table(struct intel_engine_cs *engine,
888 			   const struct drm_i915_cmd_table *cmd_tables,
889 			   int cmd_table_count)
890 {
891 	int i, j;
892 
893 	hash_init(engine->cmd_hash);
894 
895 	for (i = 0; i < cmd_table_count; i++) {
896 		const struct drm_i915_cmd_table *table = &cmd_tables[i];
897 
898 		for (j = 0; j < table->count; j++) {
899 			const struct drm_i915_cmd_descriptor *desc =
900 				&table->table[j];
901 			struct cmd_node *desc_node =
902 				kmalloc(sizeof(*desc_node), GFP_KERNEL);
903 
904 			if (!desc_node)
905 				return -ENOMEM;
906 
907 			desc_node->desc = desc;
908 			hash_add(engine->cmd_hash, &desc_node->node,
909 				 cmd_header_key(desc->cmd.value));
910 		}
911 	}
912 
913 	return 0;
914 }
915 
916 static void fini_hash_table(struct intel_engine_cs *engine)
917 {
918 	struct hlist_node *tmp;
919 	struct cmd_node *desc_node;
920 	int i;
921 
922 	hash_for_each_safe(engine->cmd_hash, i, tmp, desc_node, node) {
923 		hash_del(&desc_node->node);
924 		kfree(desc_node);
925 	}
926 }
927 
928 /**
929  * intel_engine_init_cmd_parser() - set cmd parser related fields for an engine
930  * @engine: the engine to initialize
931  *
932  * Optionally initializes fields related to batch buffer command parsing in the
933  * struct intel_engine_cs based on whether the platform requires software
934  * command parsing.
935  */
936 void intel_engine_init_cmd_parser(struct intel_engine_cs *engine)
937 {
938 	const struct drm_i915_cmd_table *cmd_tables;
939 	int cmd_table_count;
940 	int ret;
941 
942 	if (!IS_GEN(engine->i915, 7) && !(IS_GEN(engine->i915, 9) &&
943 					  engine->class == COPY_ENGINE_CLASS))
944 		return;
945 
946 	switch (engine->class) {
947 	case RENDER_CLASS:
948 		if (IS_HASWELL(engine->i915)) {
949 			cmd_tables = hsw_render_ring_cmd_table;
950 			cmd_table_count =
951 				ARRAY_SIZE(hsw_render_ring_cmd_table);
952 		} else {
953 			cmd_tables = gen7_render_cmd_table;
954 			cmd_table_count = ARRAY_SIZE(gen7_render_cmd_table);
955 		}
956 
957 		if (IS_HASWELL(engine->i915)) {
958 			engine->reg_tables = hsw_render_reg_tables;
959 			engine->reg_table_count = ARRAY_SIZE(hsw_render_reg_tables);
960 		} else {
961 			engine->reg_tables = ivb_render_reg_tables;
962 			engine->reg_table_count = ARRAY_SIZE(ivb_render_reg_tables);
963 		}
964 		engine->get_cmd_length_mask = gen7_render_get_cmd_length_mask;
965 		break;
966 	case VIDEO_DECODE_CLASS:
967 		cmd_tables = gen7_video_cmd_table;
968 		cmd_table_count = ARRAY_SIZE(gen7_video_cmd_table);
969 		engine->get_cmd_length_mask = gen7_bsd_get_cmd_length_mask;
970 		break;
971 	case COPY_ENGINE_CLASS:
972 		engine->get_cmd_length_mask = gen7_blt_get_cmd_length_mask;
973 		if (IS_GEN(engine->i915, 9)) {
974 			cmd_tables = gen9_blt_cmd_table;
975 			cmd_table_count = ARRAY_SIZE(gen9_blt_cmd_table);
976 			engine->get_cmd_length_mask =
977 				gen9_blt_get_cmd_length_mask;
978 
979 			/* BCS Engine unsafe without parser */
980 			engine->flags |= I915_ENGINE_REQUIRES_CMD_PARSER;
981 		} else if (IS_HASWELL(engine->i915)) {
982 			cmd_tables = hsw_blt_ring_cmd_table;
983 			cmd_table_count = ARRAY_SIZE(hsw_blt_ring_cmd_table);
984 		} else {
985 			cmd_tables = gen7_blt_cmd_table;
986 			cmd_table_count = ARRAY_SIZE(gen7_blt_cmd_table);
987 		}
988 
989 		if (IS_GEN(engine->i915, 9)) {
990 			engine->reg_tables = gen9_blt_reg_tables;
991 			engine->reg_table_count =
992 				ARRAY_SIZE(gen9_blt_reg_tables);
993 		} else if (IS_HASWELL(engine->i915)) {
994 			engine->reg_tables = hsw_blt_reg_tables;
995 			engine->reg_table_count = ARRAY_SIZE(hsw_blt_reg_tables);
996 		} else {
997 			engine->reg_tables = ivb_blt_reg_tables;
998 			engine->reg_table_count = ARRAY_SIZE(ivb_blt_reg_tables);
999 		}
1000 		break;
1001 	case VIDEO_ENHANCEMENT_CLASS:
1002 		cmd_tables = hsw_vebox_cmd_table;
1003 		cmd_table_count = ARRAY_SIZE(hsw_vebox_cmd_table);
1004 		/* VECS can use the same length_mask function as VCS */
1005 		engine->get_cmd_length_mask = gen7_bsd_get_cmd_length_mask;
1006 		break;
1007 	default:
1008 		MISSING_CASE(engine->class);
1009 		return;
1010 	}
1011 
1012 	if (!validate_cmds_sorted(engine, cmd_tables, cmd_table_count)) {
1013 		DRM_ERROR("%s: command descriptions are not sorted\n",
1014 			  engine->name);
1015 		return;
1016 	}
1017 	if (!validate_regs_sorted(engine)) {
1018 		DRM_ERROR("%s: registers are not sorted\n", engine->name);
1019 		return;
1020 	}
1021 
1022 	ret = init_hash_table(engine, cmd_tables, cmd_table_count);
1023 	if (ret) {
1024 		DRM_ERROR("%s: initialised failed!\n", engine->name);
1025 		fini_hash_table(engine);
1026 		return;
1027 	}
1028 
1029 	engine->flags |= I915_ENGINE_USING_CMD_PARSER;
1030 }
1031 
1032 /**
1033  * intel_engine_cleanup_cmd_parser() - clean up cmd parser related fields
1034  * @engine: the engine to clean up
1035  *
1036  * Releases any resources related to command parsing that may have been
1037  * initialized for the specified engine.
1038  */
1039 void intel_engine_cleanup_cmd_parser(struct intel_engine_cs *engine)
1040 {
1041 	if (!intel_engine_using_cmd_parser(engine))
1042 		return;
1043 
1044 	fini_hash_table(engine);
1045 }
1046 
1047 static const struct drm_i915_cmd_descriptor*
1048 find_cmd_in_table(struct intel_engine_cs *engine,
1049 		  u32 cmd_header)
1050 {
1051 	struct cmd_node *desc_node;
1052 
1053 	hash_for_each_possible(engine->cmd_hash, desc_node, node,
1054 			       cmd_header_key(cmd_header)) {
1055 		const struct drm_i915_cmd_descriptor *desc = desc_node->desc;
1056 		if (((cmd_header ^ desc->cmd.value) & desc->cmd.mask) == 0)
1057 			return desc;
1058 	}
1059 
1060 	return NULL;
1061 }
1062 
1063 /*
1064  * Returns a pointer to a descriptor for the command specified by cmd_header.
1065  *
1066  * The caller must supply space for a default descriptor via the default_desc
1067  * parameter. If no descriptor for the specified command exists in the engine's
1068  * command parser tables, this function fills in default_desc based on the
1069  * engine's default length encoding and returns default_desc.
1070  */
1071 static const struct drm_i915_cmd_descriptor*
1072 find_cmd(struct intel_engine_cs *engine,
1073 	 u32 cmd_header,
1074 	 const struct drm_i915_cmd_descriptor *desc,
1075 	 struct drm_i915_cmd_descriptor *default_desc)
1076 {
1077 	u32 mask;
1078 
1079 	if (((cmd_header ^ desc->cmd.value) & desc->cmd.mask) == 0)
1080 		return desc;
1081 
1082 	desc = find_cmd_in_table(engine, cmd_header);
1083 	if (desc)
1084 		return desc;
1085 
1086 	mask = engine->get_cmd_length_mask(cmd_header);
1087 	if (!mask)
1088 		return NULL;
1089 
1090 	default_desc->cmd.value = cmd_header;
1091 	default_desc->cmd.mask = ~0u << MIN_OPCODE_SHIFT;
1092 	default_desc->length.mask = mask;
1093 	default_desc->flags = CMD_DESC_SKIP;
1094 	return default_desc;
1095 }
1096 
1097 static const struct drm_i915_reg_descriptor *
1098 __find_reg(const struct drm_i915_reg_descriptor *table, int count, u32 addr)
1099 {
1100 	int start = 0, end = count;
1101 	while (start < end) {
1102 		int mid = start + (end - start) / 2;
1103 		int ret = addr - i915_mmio_reg_offset(table[mid].addr);
1104 		if (ret < 0)
1105 			end = mid;
1106 		else if (ret > 0)
1107 			start = mid + 1;
1108 		else
1109 			return &table[mid];
1110 	}
1111 	return NULL;
1112 }
1113 
1114 static const struct drm_i915_reg_descriptor *
1115 find_reg(const struct intel_engine_cs *engine, u32 addr)
1116 {
1117 	const struct drm_i915_reg_table *table = engine->reg_tables;
1118 	const struct drm_i915_reg_descriptor *reg = NULL;
1119 	int count = engine->reg_table_count;
1120 
1121 	for (; !reg && (count > 0); ++table, --count)
1122 		reg = __find_reg(table->regs, table->num_regs, addr);
1123 
1124 	return reg;
1125 }
1126 
1127 /* Returns a vmap'd pointer to dst_obj, which the caller must unmap */
1128 static u32 *copy_batch(struct drm_i915_gem_object *dst_obj,
1129 		       struct drm_i915_gem_object *src_obj,
1130 		       u32 offset, u32 length)
1131 {
1132 	bool needs_clflush;
1133 	void *dst, *src;
1134 	int ret;
1135 
1136 	dst = i915_gem_object_pin_map(dst_obj, I915_MAP_FORCE_WB);
1137 	if (IS_ERR(dst))
1138 		return dst;
1139 
1140 	ret = i915_gem_object_pin_pages(src_obj);
1141 	if (ret) {
1142 		i915_gem_object_unpin_map(dst_obj);
1143 		return ERR_PTR(ret);
1144 	}
1145 
1146 	needs_clflush =
1147 		!(src_obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_READ);
1148 
1149 	src = ERR_PTR(-ENODEV);
1150 	if (needs_clflush && i915_has_memcpy_from_wc()) {
1151 		src = i915_gem_object_pin_map(src_obj, I915_MAP_WC);
1152 		if (!IS_ERR(src)) {
1153 			i915_unaligned_memcpy_from_wc(dst,
1154 						      src + offset,
1155 						      length);
1156 			i915_gem_object_unpin_map(src_obj);
1157 		}
1158 	}
1159 	if (IS_ERR(src)) {
1160 		void *ptr;
1161 		int x, n;
1162 
1163 		/*
1164 		 * We can avoid clflushing partial cachelines before the write
1165 		 * if we only every write full cache-lines. Since we know that
1166 		 * both the source and destination are in multiples of
1167 		 * PAGE_SIZE, we can simply round up to the next cacheline.
1168 		 * We don't care about copying too much here as we only
1169 		 * validate up to the end of the batch.
1170 		 */
1171 		if (!(dst_obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_READ))
1172 			length = round_up(length,
1173 					  boot_cpu_data.x86_clflush_size);
1174 
1175 		ptr = dst;
1176 		x = offset_in_page(offset);
1177 		for (n = offset >> PAGE_SHIFT; length; n++) {
1178 			int len = min_t(int, length, PAGE_SIZE - x);
1179 
1180 			src = kmap_atomic(i915_gem_object_get_page(src_obj, n));
1181 			if (needs_clflush)
1182 				drm_clflush_virt_range(src + x, len);
1183 			memcpy(ptr, src + x, len);
1184 			kunmap_atomic(src);
1185 
1186 			ptr += len;
1187 			length -= len;
1188 			x = 0;
1189 		}
1190 	}
1191 
1192 	i915_gem_object_unpin_pages(src_obj);
1193 
1194 	/* dst_obj is returned with vmap pinned */
1195 	return dst;
1196 }
1197 
1198 static bool check_cmd(const struct intel_engine_cs *engine,
1199 		      const struct drm_i915_cmd_descriptor *desc,
1200 		      const u32 *cmd, u32 length)
1201 {
1202 	if (desc->flags & CMD_DESC_SKIP)
1203 		return true;
1204 
1205 	if (desc->flags & CMD_DESC_REJECT) {
1206 		DRM_DEBUG("CMD: Rejected command: 0x%08X\n", *cmd);
1207 		return false;
1208 	}
1209 
1210 	if (desc->flags & CMD_DESC_REGISTER) {
1211 		/*
1212 		 * Get the distance between individual register offset
1213 		 * fields if the command can perform more than one
1214 		 * access at a time.
1215 		 */
1216 		const u32 step = desc->reg.step ? desc->reg.step : length;
1217 		u32 offset;
1218 
1219 		for (offset = desc->reg.offset; offset < length;
1220 		     offset += step) {
1221 			const u32 reg_addr = cmd[offset] & desc->reg.mask;
1222 			const struct drm_i915_reg_descriptor *reg =
1223 				find_reg(engine, reg_addr);
1224 
1225 			if (!reg) {
1226 				DRM_DEBUG("CMD: Rejected register 0x%08X in command: 0x%08X (%s)\n",
1227 					  reg_addr, *cmd, engine->name);
1228 				return false;
1229 			}
1230 
1231 			/*
1232 			 * Check the value written to the register against the
1233 			 * allowed mask/value pair given in the whitelist entry.
1234 			 */
1235 			if (reg->mask) {
1236 				if (desc->cmd.value == MI_LOAD_REGISTER_MEM) {
1237 					DRM_DEBUG("CMD: Rejected LRM to masked register 0x%08X\n",
1238 						  reg_addr);
1239 					return false;
1240 				}
1241 
1242 				if (desc->cmd.value == MI_LOAD_REGISTER_REG) {
1243 					DRM_DEBUG("CMD: Rejected LRR to masked register 0x%08X\n",
1244 						  reg_addr);
1245 					return false;
1246 				}
1247 
1248 				if (desc->cmd.value == MI_LOAD_REGISTER_IMM(1) &&
1249 				    (offset + 2 > length ||
1250 				     (cmd[offset + 1] & reg->mask) != reg->value)) {
1251 					DRM_DEBUG("CMD: Rejected LRI to masked register 0x%08X\n",
1252 						  reg_addr);
1253 					return false;
1254 				}
1255 			}
1256 		}
1257 	}
1258 
1259 	if (desc->flags & CMD_DESC_BITMASK) {
1260 		int i;
1261 
1262 		for (i = 0; i < MAX_CMD_DESC_BITMASKS; i++) {
1263 			u32 dword;
1264 
1265 			if (desc->bits[i].mask == 0)
1266 				break;
1267 
1268 			if (desc->bits[i].condition_mask != 0) {
1269 				u32 offset =
1270 					desc->bits[i].condition_offset;
1271 				u32 condition = cmd[offset] &
1272 					desc->bits[i].condition_mask;
1273 
1274 				if (condition == 0)
1275 					continue;
1276 			}
1277 
1278 			if (desc->bits[i].offset >= length) {
1279 				DRM_DEBUG("CMD: Rejected command 0x%08X, too short to check bitmask (%s)\n",
1280 					  *cmd, engine->name);
1281 				return false;
1282 			}
1283 
1284 			dword = cmd[desc->bits[i].offset] &
1285 				desc->bits[i].mask;
1286 
1287 			if (dword != desc->bits[i].expected) {
1288 				DRM_DEBUG("CMD: Rejected command 0x%08X for bitmask 0x%08X (exp=0x%08X act=0x%08X) (%s)\n",
1289 					  *cmd,
1290 					  desc->bits[i].mask,
1291 					  desc->bits[i].expected,
1292 					  dword, engine->name);
1293 				return false;
1294 			}
1295 		}
1296 	}
1297 
1298 	return true;
1299 }
1300 
1301 static int check_bbstart(u32 *cmd, u32 offset, u32 length,
1302 			 u32 batch_length,
1303 			 u64 batch_addr,
1304 			 u64 shadow_addr,
1305 			 const unsigned long *jump_whitelist)
1306 {
1307 	u64 jump_offset, jump_target;
1308 	u32 target_cmd_offset, target_cmd_index;
1309 
1310 	/* For igt compatibility on older platforms */
1311 	if (!jump_whitelist) {
1312 		DRM_DEBUG("CMD: Rejecting BB_START for ggtt based submission\n");
1313 		return -EACCES;
1314 	}
1315 
1316 	if (length != 3) {
1317 		DRM_DEBUG("CMD: Recursive BB_START with bad length(%u)\n",
1318 			  length);
1319 		return -EINVAL;
1320 	}
1321 
1322 	jump_target = *(u64 *)(cmd + 1);
1323 	jump_offset = jump_target - batch_addr;
1324 
1325 	/*
1326 	 * Any underflow of jump_target is guaranteed to be outside the range
1327 	 * of a u32, so >= test catches both too large and too small
1328 	 */
1329 	if (jump_offset >= batch_length) {
1330 		DRM_DEBUG("CMD: BB_START to 0x%llx jumps out of BB\n",
1331 			  jump_target);
1332 		return -EINVAL;
1333 	}
1334 
1335 	/*
1336 	 * This cannot overflow a u32 because we already checked jump_offset
1337 	 * is within the BB, and the batch_length is a u32
1338 	 */
1339 	target_cmd_offset = lower_32_bits(jump_offset);
1340 	target_cmd_index = target_cmd_offset / sizeof(u32);
1341 
1342 	*(u64 *)(cmd + 1) = shadow_addr + target_cmd_offset;
1343 
1344 	if (target_cmd_index == offset)
1345 		return 0;
1346 
1347 	if (IS_ERR(jump_whitelist))
1348 		return PTR_ERR(jump_whitelist);
1349 
1350 	if (!test_bit(target_cmd_index, jump_whitelist)) {
1351 		DRM_DEBUG("CMD: BB_START to 0x%llx not a previously executed cmd\n",
1352 			  jump_target);
1353 		return -EINVAL;
1354 	}
1355 
1356 	return 0;
1357 }
1358 
1359 static unsigned long *alloc_whitelist(u32 batch_length)
1360 {
1361 	unsigned long *jmp;
1362 
1363 	/*
1364 	 * We expect batch_length to be less than 256KiB for known users,
1365 	 * i.e. we need at most an 8KiB bitmap allocation which should be
1366 	 * reasonably cheap due to kmalloc caches.
1367 	 */
1368 
1369 	/* Prefer to report transient allocation failure rather than hit oom */
1370 	jmp = bitmap_zalloc(DIV_ROUND_UP(batch_length, sizeof(u32)),
1371 			    GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN);
1372 	if (!jmp)
1373 		return ERR_PTR(-ENOMEM);
1374 
1375 	return jmp;
1376 }
1377 
1378 #define LENGTH_BIAS 2
1379 
1380 static bool shadow_needs_clflush(struct drm_i915_gem_object *obj)
1381 {
1382 	return !(obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_WRITE);
1383 }
1384 
1385 /**
1386  * intel_engine_cmd_parser() - parse a batch buffer for privilege violations
1387  * @engine: the engine on which the batch is to execute
1388  * @batch: the batch buffer in question
1389  * @batch_offset: byte offset in the batch at which execution starts
1390  * @batch_length: length of the commands in batch_obj
1391  * @shadow: validated copy of the batch buffer in question
1392  * @trampoline: whether to emit a conditional trampoline at the end of the batch
1393  *
1394  * Parses the specified batch buffer looking for privilege violations as
1395  * described in the overview.
1396  *
1397  * Return: non-zero if the parser finds violations or otherwise fails; -EACCES
1398  * if the batch appears legal but should use hardware parsing
1399  */
1400 int intel_engine_cmd_parser(struct intel_engine_cs *engine,
1401 			    struct i915_vma *batch,
1402 			    u32 batch_offset,
1403 			    u32 batch_length,
1404 			    struct i915_vma *shadow,
1405 			    bool trampoline)
1406 {
1407 	u32 *cmd, *batch_end, offset = 0;
1408 	struct drm_i915_cmd_descriptor default_desc = noop_desc;
1409 	const struct drm_i915_cmd_descriptor *desc = &default_desc;
1410 	unsigned long *jump_whitelist;
1411 	u64 batch_addr, shadow_addr;
1412 	int ret = 0;
1413 
1414 	GEM_BUG_ON(!IS_ALIGNED(batch_offset, sizeof(*cmd)));
1415 	GEM_BUG_ON(!IS_ALIGNED(batch_length, sizeof(*cmd)));
1416 	GEM_BUG_ON(range_overflows_t(u64, batch_offset, batch_length,
1417 				     batch->size));
1418 	GEM_BUG_ON(!batch_length);
1419 
1420 	cmd = copy_batch(shadow->obj, batch->obj, batch_offset, batch_length);
1421 	if (IS_ERR(cmd)) {
1422 		DRM_DEBUG("CMD: Failed to copy batch\n");
1423 		return PTR_ERR(cmd);
1424 	}
1425 
1426 	jump_whitelist = NULL;
1427 	if (!trampoline)
1428 		/* Defer failure until attempted use */
1429 		jump_whitelist = alloc_whitelist(batch_length);
1430 
1431 	shadow_addr = gen8_canonical_addr(shadow->node.start);
1432 	batch_addr = gen8_canonical_addr(batch->node.start + batch_offset);
1433 
1434 	/*
1435 	 * We use the batch length as size because the shadow object is as
1436 	 * large or larger and copy_batch() will write MI_NOPs to the extra
1437 	 * space. Parsing should be faster in some cases this way.
1438 	 */
1439 	batch_end = cmd + batch_length / sizeof(*batch_end);
1440 	do {
1441 		u32 length;
1442 
1443 		if (*cmd == MI_BATCH_BUFFER_END)
1444 			break;
1445 
1446 		desc = find_cmd(engine, *cmd, desc, &default_desc);
1447 		if (!desc) {
1448 			DRM_DEBUG("CMD: Unrecognized command: 0x%08X\n", *cmd);
1449 			ret = -EINVAL;
1450 			break;
1451 		}
1452 
1453 		if (desc->flags & CMD_DESC_FIXED)
1454 			length = desc->length.fixed;
1455 		else
1456 			length = (*cmd & desc->length.mask) + LENGTH_BIAS;
1457 
1458 		if ((batch_end - cmd) < length) {
1459 			DRM_DEBUG("CMD: Command length exceeds batch length: 0x%08X length=%u batchlen=%td\n",
1460 				  *cmd,
1461 				  length,
1462 				  batch_end - cmd);
1463 			ret = -EINVAL;
1464 			break;
1465 		}
1466 
1467 		if (!check_cmd(engine, desc, cmd, length)) {
1468 			ret = -EACCES;
1469 			break;
1470 		}
1471 
1472 		if (desc->cmd.value == MI_BATCH_BUFFER_START) {
1473 			ret = check_bbstart(cmd, offset, length, batch_length,
1474 					    batch_addr, shadow_addr,
1475 					    jump_whitelist);
1476 			break;
1477 		}
1478 
1479 		if (!IS_ERR_OR_NULL(jump_whitelist))
1480 			__set_bit(offset, jump_whitelist);
1481 
1482 		cmd += length;
1483 		offset += length;
1484 		if  (cmd >= batch_end) {
1485 			DRM_DEBUG("CMD: Got to the end of the buffer w/o a BBE cmd!\n");
1486 			ret = -EINVAL;
1487 			break;
1488 		}
1489 	} while (1);
1490 
1491 	if (trampoline) {
1492 		/*
1493 		 * With the trampoline, the shadow is executed twice.
1494 		 *
1495 		 *   1 - starting at offset 0, in privileged mode
1496 		 *   2 - starting at offset batch_len, as non-privileged
1497 		 *
1498 		 * Only if the batch is valid and safe to execute, do we
1499 		 * allow the first privileged execution to proceed. If not,
1500 		 * we terminate the first batch and use the second batchbuffer
1501 		 * entry to chain to the original unsafe non-privileged batch,
1502 		 * leaving it to the HW to validate.
1503 		 */
1504 		*batch_end = MI_BATCH_BUFFER_END;
1505 
1506 		if (ret) {
1507 			/* Batch unsafe to execute with privileges, cancel! */
1508 			cmd = page_mask_bits(shadow->obj->mm.mapping);
1509 			*cmd = MI_BATCH_BUFFER_END;
1510 
1511 			/* If batch is unsafe but valid, jump to the original */
1512 			if (ret == -EACCES) {
1513 				unsigned int flags;
1514 
1515 				flags = MI_BATCH_NON_SECURE_I965;
1516 				if (IS_HASWELL(engine->i915))
1517 					flags = MI_BATCH_NON_SECURE_HSW;
1518 
1519 				GEM_BUG_ON(!IS_GEN_RANGE(engine->i915, 6, 7));
1520 				__gen6_emit_bb_start(batch_end,
1521 						     batch_addr,
1522 						     flags);
1523 
1524 				ret = 0; /* allow execution */
1525 			}
1526 		}
1527 
1528 		if (shadow_needs_clflush(shadow->obj))
1529 			drm_clflush_virt_range(batch_end, 8);
1530 	}
1531 
1532 	if (shadow_needs_clflush(shadow->obj)) {
1533 		void *ptr = page_mask_bits(shadow->obj->mm.mapping);
1534 
1535 		drm_clflush_virt_range(ptr, (void *)(cmd + 1) - ptr);
1536 	}
1537 
1538 	if (!IS_ERR_OR_NULL(jump_whitelist))
1539 		kfree(jump_whitelist);
1540 	i915_gem_object_unpin_map(shadow->obj);
1541 	return ret;
1542 }
1543 
1544 /**
1545  * i915_cmd_parser_get_version() - get the cmd parser version number
1546  * @dev_priv: i915 device private
1547  *
1548  * The cmd parser maintains a simple increasing integer version number suitable
1549  * for passing to userspace clients to determine what operations are permitted.
1550  *
1551  * Return: the current version number of the cmd parser
1552  */
1553 int i915_cmd_parser_get_version(struct drm_i915_private *dev_priv)
1554 {
1555 	struct intel_engine_cs *engine;
1556 	bool active = false;
1557 
1558 	/* If the command parser is not enabled, report 0 - unsupported */
1559 	for_each_uabi_engine(engine, dev_priv) {
1560 		if (intel_engine_using_cmd_parser(engine)) {
1561 			active = true;
1562 			break;
1563 		}
1564 	}
1565 	if (!active)
1566 		return 0;
1567 
1568 	/*
1569 	 * Command parser version history
1570 	 *
1571 	 * 1. Initial version. Checks batches and reports violations, but leaves
1572 	 *    hardware parsing enabled (so does not allow new use cases).
1573 	 * 2. Allow access to the MI_PREDICATE_SRC0 and
1574 	 *    MI_PREDICATE_SRC1 registers.
1575 	 * 3. Allow access to the GPGPU_THREADS_DISPATCHED register.
1576 	 * 4. L3 atomic chicken bits of HSW_SCRATCH1 and HSW_ROW_CHICKEN3.
1577 	 * 5. GPGPU dispatch compute indirect registers.
1578 	 * 6. TIMESTAMP register and Haswell CS GPR registers
1579 	 * 7. Allow MI_LOAD_REGISTER_REG between whitelisted registers.
1580 	 * 8. Don't report cmd_check() failures as EINVAL errors to userspace;
1581 	 *    rely on the HW to NOOP disallowed commands as it would without
1582 	 *    the parser enabled.
1583 	 * 9. Don't whitelist or handle oacontrol specially, as ownership
1584 	 *    for oacontrol state is moving to i915-perf.
1585 	 * 10. Support for Gen9 BCS Parsing
1586 	 */
1587 	return 10;
1588 }
1589