drm/i915: Add TIMESTAMP to register whitelist
[cascardo/linux.git] / drivers / gpu / drm / i915 / i915_cmd_parser.c
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 "i915_drv.h"
29
30 /**
31  * DOC: batch buffer command parser
32  *
33  * Motivation:
34  * Certain OpenGL features (e.g. transform feedback, performance monitoring)
35  * require userspace code to submit batches containing commands such as
36  * MI_LOAD_REGISTER_IMM to access various registers. Unfortunately, some
37  * generations of the hardware will noop these commands in "unsecure" batches
38  * (which includes all userspace batches submitted via i915) even though the
39  * commands may be safe and represent the intended programming model of the
40  * device.
41  *
42  * The software command parser is similar in operation to the command parsing
43  * done in hardware for unsecure batches. However, the software parser allows
44  * some operations that would be noop'd by hardware, if the parser determines
45  * the operation is safe, and submits the batch as "secure" to prevent hardware
46  * parsing.
47  *
48  * Threats:
49  * At a high level, the hardware (and software) checks attempt to prevent
50  * granting userspace undue privileges. There are three categories of privilege.
51  *
52  * First, commands which are explicitly defined as privileged or which should
53  * only be used by the kernel driver. The parser generally rejects such
54  * commands, though it may allow some from the drm master process.
55  *
56  * Second, commands which access registers. To support correct/enhanced
57  * userspace functionality, particularly certain OpenGL extensions, the parser
58  * provides a whitelist of registers which userspace may safely access (for both
59  * normal and drm master processes).
60  *
61  * Third, commands which access privileged memory (i.e. GGTT, HWS page, etc).
62  * The parser always rejects such commands.
63  *
64  * The majority of the problematic commands fall in the MI_* range, with only a
65  * few specific commands on each ring (e.g. PIPE_CONTROL and MI_FLUSH_DW).
66  *
67  * Implementation:
68  * Each ring maintains tables of commands and registers which the parser uses in
69  * scanning batch buffers submitted to that ring.
70  *
71  * Since the set of commands that the parser must check for is significantly
72  * smaller than the number of commands supported, the parser tables contain only
73  * those commands required by the parser. This generally works because command
74  * opcode ranges have standard command length encodings. So for commands that
75  * the parser does not need to check, it can easily skip them. This is
76  * implemented via a per-ring length decoding vfunc.
77  *
78  * Unfortunately, there are a number of commands that do not follow the standard
79  * length encoding for their opcode range, primarily amongst the MI_* commands.
80  * To handle this, the parser provides a way to define explicit "skip" entries
81  * in the per-ring command tables.
82  *
83  * Other command table entries map fairly directly to high level categories
84  * mentioned above: rejected, master-only, register whitelist. The parser
85  * implements a number of checks, including the privileged memory checks, via a
86  * general bitmasking mechanism.
87  */
88
89 #define STD_MI_OPCODE_MASK  0xFF800000
90 #define STD_3D_OPCODE_MASK  0xFFFF0000
91 #define STD_2D_OPCODE_MASK  0xFFC00000
92 #define STD_MFX_OPCODE_MASK 0xFFFF0000
93
94 #define CMD(op, opm, f, lm, fl, ...)                            \
95         {                                                       \
96                 .flags = (fl) | ((f) ? CMD_DESC_FIXED : 0),     \
97                 .cmd = { (op), (opm) },                         \
98                 .length = { (lm) },                             \
99                 __VA_ARGS__                                     \
100         }
101
102 /* Convenience macros to compress the tables */
103 #define SMI STD_MI_OPCODE_MASK
104 #define S3D STD_3D_OPCODE_MASK
105 #define S2D STD_2D_OPCODE_MASK
106 #define SMFX STD_MFX_OPCODE_MASK
107 #define F true
108 #define S CMD_DESC_SKIP
109 #define R CMD_DESC_REJECT
110 #define W CMD_DESC_REGISTER
111 #define B CMD_DESC_BITMASK
112 #define M CMD_DESC_MASTER
113
114 /*            Command                          Mask   Fixed Len   Action
115               ---------------------------------------------------------- */
116 static const struct drm_i915_cmd_descriptor common_cmds[] = {
117         CMD(  MI_NOOP,                          SMI,    F,  1,      S  ),
118         CMD(  MI_USER_INTERRUPT,                SMI,    F,  1,      R  ),
119         CMD(  MI_WAIT_FOR_EVENT,                SMI,    F,  1,      M  ),
120         CMD(  MI_ARB_CHECK,                     SMI,    F,  1,      S  ),
121         CMD(  MI_REPORT_HEAD,                   SMI,    F,  1,      S  ),
122         CMD(  MI_SUSPEND_FLUSH,                 SMI,    F,  1,      S  ),
123         CMD(  MI_SEMAPHORE_MBOX,                SMI,   !F,  0xFF,   R  ),
124         CMD(  MI_STORE_DWORD_INDEX,             SMI,   !F,  0xFF,   R  ),
125         CMD(  MI_LOAD_REGISTER_IMM(1),          SMI,   !F,  0xFF,   W,
126               .reg = { .offset = 1, .mask = 0x007FFFFC, .step = 2 }    ),
127         CMD(  MI_STORE_REGISTER_MEM,            SMI,    F,  3,     W | B,
128               .reg = { .offset = 1, .mask = 0x007FFFFC },
129               .bits = {{
130                         .offset = 0,
131                         .mask = MI_GLOBAL_GTT,
132                         .expected = 0,
133               }},                                                      ),
134         CMD(  MI_LOAD_REGISTER_MEM,             SMI,    F,  3,     W | B,
135               .reg = { .offset = 1, .mask = 0x007FFFFC },
136               .bits = {{
137                         .offset = 0,
138                         .mask = MI_GLOBAL_GTT,
139                         .expected = 0,
140               }},                                                      ),
141         /*
142          * MI_BATCH_BUFFER_START requires some special handling. It's not
143          * really a 'skip' action but it doesn't seem like it's worth adding
144          * a new action. See i915_parse_cmds().
145          */
146         CMD(  MI_BATCH_BUFFER_START,            SMI,   !F,  0xFF,   S  ),
147 };
148
149 static const struct drm_i915_cmd_descriptor render_cmds[] = {
150         CMD(  MI_FLUSH,                         SMI,    F,  1,      S  ),
151         CMD(  MI_ARB_ON_OFF,                    SMI,    F,  1,      R  ),
152         CMD(  MI_PREDICATE,                     SMI,    F,  1,      S  ),
153         CMD(  MI_TOPOLOGY_FILTER,               SMI,    F,  1,      S  ),
154         CMD(  MI_SET_APPID,                     SMI,    F,  1,      S  ),
155         CMD(  MI_DISPLAY_FLIP,                  SMI,   !F,  0xFF,   R  ),
156         CMD(  MI_SET_CONTEXT,                   SMI,   !F,  0xFF,   R  ),
157         CMD(  MI_URB_CLEAR,                     SMI,   !F,  0xFF,   S  ),
158         CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0x3F,   B,
159               .bits = {{
160                         .offset = 0,
161                         .mask = MI_GLOBAL_GTT,
162                         .expected = 0,
163               }},                                                      ),
164         CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0xFF,   R  ),
165         CMD(  MI_CLFLUSH,                       SMI,   !F,  0x3FF,  B,
166               .bits = {{
167                         .offset = 0,
168                         .mask = MI_GLOBAL_GTT,
169                         .expected = 0,
170               }},                                                      ),
171         CMD(  MI_REPORT_PERF_COUNT,             SMI,   !F,  0x3F,   B,
172               .bits = {{
173                         .offset = 1,
174                         .mask = MI_REPORT_PERF_COUNT_GGTT,
175                         .expected = 0,
176               }},                                                      ),
177         CMD(  MI_CONDITIONAL_BATCH_BUFFER_END,  SMI,   !F,  0xFF,   B,
178               .bits = {{
179                         .offset = 0,
180                         .mask = MI_GLOBAL_GTT,
181                         .expected = 0,
182               }},                                                      ),
183         CMD(  GFX_OP_3DSTATE_VF_STATISTICS,     S3D,    F,  1,      S  ),
184         CMD(  PIPELINE_SELECT,                  S3D,    F,  1,      S  ),
185         CMD(  MEDIA_VFE_STATE,                  S3D,   !F,  0xFFFF, B,
186               .bits = {{
187                         .offset = 2,
188                         .mask = MEDIA_VFE_STATE_MMIO_ACCESS_MASK,
189                         .expected = 0,
190               }},                                                      ),
191         CMD(  GPGPU_OBJECT,                     S3D,   !F,  0xFF,   S  ),
192         CMD(  GPGPU_WALKER,                     S3D,   !F,  0xFF,   S  ),
193         CMD(  GFX_OP_3DSTATE_SO_DECL_LIST,      S3D,   !F,  0x1FF,  S  ),
194         CMD(  GFX_OP_PIPE_CONTROL(5),           S3D,   !F,  0xFF,   B,
195               .bits = {{
196                         .offset = 1,
197                         .mask = (PIPE_CONTROL_MMIO_WRITE | PIPE_CONTROL_NOTIFY),
198                         .expected = 0,
199               },
200               {
201                         .offset = 1,
202                         .mask = (PIPE_CONTROL_GLOBAL_GTT_IVB |
203                                  PIPE_CONTROL_STORE_DATA_INDEX),
204                         .expected = 0,
205                         .condition_offset = 1,
206                         .condition_mask = PIPE_CONTROL_POST_SYNC_OP_MASK,
207               }},                                                      ),
208 };
209
210 static const struct drm_i915_cmd_descriptor hsw_render_cmds[] = {
211         CMD(  MI_SET_PREDICATE,                 SMI,    F,  1,      S  ),
212         CMD(  MI_RS_CONTROL,                    SMI,    F,  1,      S  ),
213         CMD(  MI_URB_ATOMIC_ALLOC,              SMI,    F,  1,      S  ),
214         CMD(  MI_SET_APPID,                     SMI,    F,  1,      S  ),
215         CMD(  MI_RS_CONTEXT,                    SMI,    F,  1,      S  ),
216         CMD(  MI_LOAD_SCAN_LINES_INCL,          SMI,   !F,  0x3F,   M  ),
217         CMD(  MI_LOAD_SCAN_LINES_EXCL,          SMI,   !F,  0x3F,   R  ),
218         CMD(  MI_LOAD_REGISTER_REG,             SMI,   !F,  0xFF,   R  ),
219         CMD(  MI_RS_STORE_DATA_IMM,             SMI,   !F,  0xFF,   S  ),
220         CMD(  MI_LOAD_URB_MEM,                  SMI,   !F,  0xFF,   S  ),
221         CMD(  MI_STORE_URB_MEM,                 SMI,   !F,  0xFF,   S  ),
222         CMD(  GFX_OP_3DSTATE_DX9_CONSTANTF_VS,  S3D,   !F,  0x7FF,  S  ),
223         CMD(  GFX_OP_3DSTATE_DX9_CONSTANTF_PS,  S3D,   !F,  0x7FF,  S  ),
224
225         CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_VS,  S3D,   !F,  0x1FF,  S  ),
226         CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_GS,  S3D,   !F,  0x1FF,  S  ),
227         CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_HS,  S3D,   !F,  0x1FF,  S  ),
228         CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_DS,  S3D,   !F,  0x1FF,  S  ),
229         CMD(  GFX_OP_3DSTATE_BINDING_TABLE_EDIT_PS,  S3D,   !F,  0x1FF,  S  ),
230 };
231
232 static const struct drm_i915_cmd_descriptor video_cmds[] = {
233         CMD(  MI_ARB_ON_OFF,                    SMI,    F,  1,      R  ),
234         CMD(  MI_SET_APPID,                     SMI,    F,  1,      S  ),
235         CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0xFF,   B,
236               .bits = {{
237                         .offset = 0,
238                         .mask = MI_GLOBAL_GTT,
239                         .expected = 0,
240               }},                                                      ),
241         CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0x3F,   R  ),
242         CMD(  MI_FLUSH_DW,                      SMI,   !F,  0x3F,   B,
243               .bits = {{
244                         .offset = 0,
245                         .mask = MI_FLUSH_DW_NOTIFY,
246                         .expected = 0,
247               },
248               {
249                         .offset = 1,
250                         .mask = MI_FLUSH_DW_USE_GTT,
251                         .expected = 0,
252                         .condition_offset = 0,
253                         .condition_mask = MI_FLUSH_DW_OP_MASK,
254               },
255               {
256                         .offset = 0,
257                         .mask = MI_FLUSH_DW_STORE_INDEX,
258                         .expected = 0,
259                         .condition_offset = 0,
260                         .condition_mask = MI_FLUSH_DW_OP_MASK,
261               }},                                                      ),
262         CMD(  MI_CONDITIONAL_BATCH_BUFFER_END,  SMI,   !F,  0xFF,   B,
263               .bits = {{
264                         .offset = 0,
265                         .mask = MI_GLOBAL_GTT,
266                         .expected = 0,
267               }},                                                      ),
268         /*
269          * MFX_WAIT doesn't fit the way we handle length for most commands.
270          * It has a length field but it uses a non-standard length bias.
271          * It is always 1 dword though, so just treat it as fixed length.
272          */
273         CMD(  MFX_WAIT,                         SMFX,   F,  1,      S  ),
274 };
275
276 static const struct drm_i915_cmd_descriptor vecs_cmds[] = {
277         CMD(  MI_ARB_ON_OFF,                    SMI,    F,  1,      R  ),
278         CMD(  MI_SET_APPID,                     SMI,    F,  1,      S  ),
279         CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0xFF,   B,
280               .bits = {{
281                         .offset = 0,
282                         .mask = MI_GLOBAL_GTT,
283                         .expected = 0,
284               }},                                                      ),
285         CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0x3F,   R  ),
286         CMD(  MI_FLUSH_DW,                      SMI,   !F,  0x3F,   B,
287               .bits = {{
288                         .offset = 0,
289                         .mask = MI_FLUSH_DW_NOTIFY,
290                         .expected = 0,
291               },
292               {
293                         .offset = 1,
294                         .mask = MI_FLUSH_DW_USE_GTT,
295                         .expected = 0,
296                         .condition_offset = 0,
297                         .condition_mask = MI_FLUSH_DW_OP_MASK,
298               },
299               {
300                         .offset = 0,
301                         .mask = MI_FLUSH_DW_STORE_INDEX,
302                         .expected = 0,
303                         .condition_offset = 0,
304                         .condition_mask = MI_FLUSH_DW_OP_MASK,
305               }},                                                      ),
306         CMD(  MI_CONDITIONAL_BATCH_BUFFER_END,  SMI,   !F,  0xFF,   B,
307               .bits = {{
308                         .offset = 0,
309                         .mask = MI_GLOBAL_GTT,
310                         .expected = 0,
311               }},                                                      ),
312 };
313
314 static const struct drm_i915_cmd_descriptor blt_cmds[] = {
315         CMD(  MI_DISPLAY_FLIP,                  SMI,   !F,  0xFF,   R  ),
316         CMD(  MI_STORE_DWORD_IMM,               SMI,   !F,  0x3FF,  B,
317               .bits = {{
318                         .offset = 0,
319                         .mask = MI_GLOBAL_GTT,
320                         .expected = 0,
321               }},                                                      ),
322         CMD(  MI_UPDATE_GTT,                    SMI,   !F,  0x3F,   R  ),
323         CMD(  MI_FLUSH_DW,                      SMI,   !F,  0x3F,   B,
324               .bits = {{
325                         .offset = 0,
326                         .mask = MI_FLUSH_DW_NOTIFY,
327                         .expected = 0,
328               },
329               {
330                         .offset = 1,
331                         .mask = MI_FLUSH_DW_USE_GTT,
332                         .expected = 0,
333                         .condition_offset = 0,
334                         .condition_mask = MI_FLUSH_DW_OP_MASK,
335               },
336               {
337                         .offset = 0,
338                         .mask = MI_FLUSH_DW_STORE_INDEX,
339                         .expected = 0,
340                         .condition_offset = 0,
341                         .condition_mask = MI_FLUSH_DW_OP_MASK,
342               }},                                                      ),
343         CMD(  COLOR_BLT,                        S2D,   !F,  0x3F,   S  ),
344         CMD(  SRC_COPY_BLT,                     S2D,   !F,  0x3F,   S  ),
345 };
346
347 static const struct drm_i915_cmd_descriptor hsw_blt_cmds[] = {
348         CMD(  MI_LOAD_SCAN_LINES_INCL,          SMI,   !F,  0x3F,   M  ),
349         CMD(  MI_LOAD_SCAN_LINES_EXCL,          SMI,   !F,  0x3F,   R  ),
350 };
351
352 #undef CMD
353 #undef SMI
354 #undef S3D
355 #undef S2D
356 #undef SMFX
357 #undef F
358 #undef S
359 #undef R
360 #undef W
361 #undef B
362 #undef M
363
364 static const struct drm_i915_cmd_table gen7_render_cmds[] = {
365         { common_cmds, ARRAY_SIZE(common_cmds) },
366         { render_cmds, ARRAY_SIZE(render_cmds) },
367 };
368
369 static const struct drm_i915_cmd_table hsw_render_ring_cmds[] = {
370         { common_cmds, ARRAY_SIZE(common_cmds) },
371         { render_cmds, ARRAY_SIZE(render_cmds) },
372         { hsw_render_cmds, ARRAY_SIZE(hsw_render_cmds) },
373 };
374
375 static const struct drm_i915_cmd_table gen7_video_cmds[] = {
376         { common_cmds, ARRAY_SIZE(common_cmds) },
377         { video_cmds, ARRAY_SIZE(video_cmds) },
378 };
379
380 static const struct drm_i915_cmd_table hsw_vebox_cmds[] = {
381         { common_cmds, ARRAY_SIZE(common_cmds) },
382         { vecs_cmds, ARRAY_SIZE(vecs_cmds) },
383 };
384
385 static const struct drm_i915_cmd_table gen7_blt_cmds[] = {
386         { common_cmds, ARRAY_SIZE(common_cmds) },
387         { blt_cmds, ARRAY_SIZE(blt_cmds) },
388 };
389
390 static const struct drm_i915_cmd_table hsw_blt_ring_cmds[] = {
391         { common_cmds, ARRAY_SIZE(common_cmds) },
392         { blt_cmds, ARRAY_SIZE(blt_cmds) },
393         { hsw_blt_cmds, ARRAY_SIZE(hsw_blt_cmds) },
394 };
395
396 /*
397  * Register whitelists, sorted by increasing register offset.
398  */
399
400 /*
401  * An individual whitelist entry granting access to register addr.  If
402  * mask is non-zero the argument of immediate register writes will be
403  * AND-ed with mask, and the command will be rejected if the result
404  * doesn't match value.
405  *
406  * Registers with non-zero mask are only allowed to be written using
407  * LRI.
408  */
409 struct drm_i915_reg_descriptor {
410         i915_reg_t addr;
411         u32 mask;
412         u32 value;
413 };
414
415 /* Convenience macro for adding 32-bit registers. */
416 #define REG32(_reg, ...) \
417         { .addr = (_reg), __VA_ARGS__ }
418
419 /*
420  * Convenience macro for adding 64-bit registers.
421  *
422  * Some registers that userspace accesses are 64 bits. The register
423  * access commands only allow 32-bit accesses. Hence, we have to include
424  * entries for both halves of the 64-bit registers.
425  */
426 #define REG64(_reg) \
427         { .addr = _reg }, \
428         { .addr = _reg ## _UDW }
429
430 #define REG64_IDX(_reg, idx) \
431         { .addr = _reg(idx) }, \
432         { .addr = _reg ## _UDW(idx) }
433
434 static const struct drm_i915_reg_descriptor gen7_render_regs[] = {
435         REG64(GPGPU_THREADS_DISPATCHED),
436         REG64(HS_INVOCATION_COUNT),
437         REG64(DS_INVOCATION_COUNT),
438         REG64(IA_VERTICES_COUNT),
439         REG64(IA_PRIMITIVES_COUNT),
440         REG64(VS_INVOCATION_COUNT),
441         REG64(GS_INVOCATION_COUNT),
442         REG64(GS_PRIMITIVES_COUNT),
443         REG64(CL_INVOCATION_COUNT),
444         REG64(CL_PRIMITIVES_COUNT),
445         REG64(PS_INVOCATION_COUNT),
446         REG64(PS_DEPTH_COUNT),
447         REG64_IDX(RING_TIMESTAMP, RENDER_RING_BASE),
448         REG32(OACONTROL), /* Only allowed for LRI and SRM. See below. */
449         REG64(MI_PREDICATE_SRC0),
450         REG64(MI_PREDICATE_SRC1),
451         REG32(GEN7_3DPRIM_END_OFFSET),
452         REG32(GEN7_3DPRIM_START_VERTEX),
453         REG32(GEN7_3DPRIM_VERTEX_COUNT),
454         REG32(GEN7_3DPRIM_INSTANCE_COUNT),
455         REG32(GEN7_3DPRIM_START_INSTANCE),
456         REG32(GEN7_3DPRIM_BASE_VERTEX),
457         REG32(GEN7_GPGPU_DISPATCHDIMX),
458         REG32(GEN7_GPGPU_DISPATCHDIMY),
459         REG32(GEN7_GPGPU_DISPATCHDIMZ),
460         REG64_IDX(GEN7_SO_NUM_PRIMS_WRITTEN, 0),
461         REG64_IDX(GEN7_SO_NUM_PRIMS_WRITTEN, 1),
462         REG64_IDX(GEN7_SO_NUM_PRIMS_WRITTEN, 2),
463         REG64_IDX(GEN7_SO_NUM_PRIMS_WRITTEN, 3),
464         REG64_IDX(GEN7_SO_PRIM_STORAGE_NEEDED, 0),
465         REG64_IDX(GEN7_SO_PRIM_STORAGE_NEEDED, 1),
466         REG64_IDX(GEN7_SO_PRIM_STORAGE_NEEDED, 2),
467         REG64_IDX(GEN7_SO_PRIM_STORAGE_NEEDED, 3),
468         REG32(GEN7_SO_WRITE_OFFSET(0)),
469         REG32(GEN7_SO_WRITE_OFFSET(1)),
470         REG32(GEN7_SO_WRITE_OFFSET(2)),
471         REG32(GEN7_SO_WRITE_OFFSET(3)),
472         REG32(GEN7_L3SQCREG1),
473         REG32(GEN7_L3CNTLREG2),
474         REG32(GEN7_L3CNTLREG3),
475         REG32(HSW_SCRATCH1,
476               .mask = ~HSW_SCRATCH1_L3_DATA_ATOMICS_DISABLE,
477               .value = 0),
478         REG32(HSW_ROW_CHICKEN3,
479               .mask = ~(HSW_ROW_CHICKEN3_L3_GLOBAL_ATOMICS_DISABLE << 16 |
480                         HSW_ROW_CHICKEN3_L3_GLOBAL_ATOMICS_DISABLE),
481               .value = 0),
482 };
483
484 static const struct drm_i915_reg_descriptor gen7_blt_regs[] = {
485         REG32(BCS_SWCTRL),
486 };
487
488 static const struct drm_i915_reg_descriptor ivb_master_regs[] = {
489         REG32(FORCEWAKE_MT),
490         REG32(DERRMR),
491         REG32(GEN7_PIPE_DE_LOAD_SL(PIPE_A)),
492         REG32(GEN7_PIPE_DE_LOAD_SL(PIPE_B)),
493         REG32(GEN7_PIPE_DE_LOAD_SL(PIPE_C)),
494 };
495
496 static const struct drm_i915_reg_descriptor hsw_master_regs[] = {
497         REG32(FORCEWAKE_MT),
498         REG32(DERRMR),
499 };
500
501 #undef REG64
502 #undef REG32
503
504 static u32 gen7_render_get_cmd_length_mask(u32 cmd_header)
505 {
506         u32 client = (cmd_header & INSTR_CLIENT_MASK) >> INSTR_CLIENT_SHIFT;
507         u32 subclient =
508                 (cmd_header & INSTR_SUBCLIENT_MASK) >> INSTR_SUBCLIENT_SHIFT;
509
510         if (client == INSTR_MI_CLIENT)
511                 return 0x3F;
512         else if (client == INSTR_RC_CLIENT) {
513                 if (subclient == INSTR_MEDIA_SUBCLIENT)
514                         return 0xFFFF;
515                 else
516                         return 0xFF;
517         }
518
519         DRM_DEBUG_DRIVER("CMD: Abnormal rcs cmd length! 0x%08X\n", cmd_header);
520         return 0;
521 }
522
523 static u32 gen7_bsd_get_cmd_length_mask(u32 cmd_header)
524 {
525         u32 client = (cmd_header & INSTR_CLIENT_MASK) >> INSTR_CLIENT_SHIFT;
526         u32 subclient =
527                 (cmd_header & INSTR_SUBCLIENT_MASK) >> INSTR_SUBCLIENT_SHIFT;
528         u32 op = (cmd_header & INSTR_26_TO_24_MASK) >> INSTR_26_TO_24_SHIFT;
529
530         if (client == INSTR_MI_CLIENT)
531                 return 0x3F;
532         else if (client == INSTR_RC_CLIENT) {
533                 if (subclient == INSTR_MEDIA_SUBCLIENT) {
534                         if (op == 6)
535                                 return 0xFFFF;
536                         else
537                                 return 0xFFF;
538                 } else
539                         return 0xFF;
540         }
541
542         DRM_DEBUG_DRIVER("CMD: Abnormal bsd cmd length! 0x%08X\n", cmd_header);
543         return 0;
544 }
545
546 static u32 gen7_blt_get_cmd_length_mask(u32 cmd_header)
547 {
548         u32 client = (cmd_header & INSTR_CLIENT_MASK) >> INSTR_CLIENT_SHIFT;
549
550         if (client == INSTR_MI_CLIENT)
551                 return 0x3F;
552         else if (client == INSTR_BC_CLIENT)
553                 return 0xFF;
554
555         DRM_DEBUG_DRIVER("CMD: Abnormal blt cmd length! 0x%08X\n", cmd_header);
556         return 0;
557 }
558
559 static bool validate_cmds_sorted(struct intel_engine_cs *engine,
560                                  const struct drm_i915_cmd_table *cmd_tables,
561                                  int cmd_table_count)
562 {
563         int i;
564         bool ret = true;
565
566         if (!cmd_tables || cmd_table_count == 0)
567                 return true;
568
569         for (i = 0; i < cmd_table_count; i++) {
570                 const struct drm_i915_cmd_table *table = &cmd_tables[i];
571                 u32 previous = 0;
572                 int j;
573
574                 for (j = 0; j < table->count; j++) {
575                         const struct drm_i915_cmd_descriptor *desc =
576                                 &table->table[j];
577                         u32 curr = desc->cmd.value & desc->cmd.mask;
578
579                         if (curr < previous) {
580                                 DRM_ERROR("CMD: table not sorted ring=%d table=%d entry=%d cmd=0x%08X prev=0x%08X\n",
581                                           engine->id, i, j, curr, previous);
582                                 ret = false;
583                         }
584
585                         previous = curr;
586                 }
587         }
588
589         return ret;
590 }
591
592 static bool check_sorted(int ring_id,
593                          const struct drm_i915_reg_descriptor *reg_table,
594                          int reg_count)
595 {
596         int i;
597         u32 previous = 0;
598         bool ret = true;
599
600         for (i = 0; i < reg_count; i++) {
601                 u32 curr = i915_mmio_reg_offset(reg_table[i].addr);
602
603                 if (curr < previous) {
604                         DRM_ERROR("CMD: table not sorted ring=%d entry=%d reg=0x%08X prev=0x%08X\n",
605                                   ring_id, i, curr, previous);
606                         ret = false;
607                 }
608
609                 previous = curr;
610         }
611
612         return ret;
613 }
614
615 static bool validate_regs_sorted(struct intel_engine_cs *engine)
616 {
617         return check_sorted(engine->id, engine->reg_table, engine->reg_count) &&
618                 check_sorted(engine->id, engine->master_reg_table,
619                              engine->master_reg_count);
620 }
621
622 struct cmd_node {
623         const struct drm_i915_cmd_descriptor *desc;
624         struct hlist_node node;
625 };
626
627 /*
628  * Different command ranges have different numbers of bits for the opcode. For
629  * example, MI commands use bits 31:23 while 3D commands use bits 31:16. The
630  * problem is that, for example, MI commands use bits 22:16 for other fields
631  * such as GGTT vs PPGTT bits. If we include those bits in the mask then when
632  * we mask a command from a batch it could hash to the wrong bucket due to
633  * non-opcode bits being set. But if we don't include those bits, some 3D
634  * commands may hash to the same bucket due to not including opcode bits that
635  * make the command unique. For now, we will risk hashing to the same bucket.
636  *
637  * If we attempt to generate a perfect hash, we should be able to look at bits
638  * 31:29 of a command from a batch buffer and use the full mask for that
639  * client. The existing INSTR_CLIENT_MASK/SHIFT defines can be used for this.
640  */
641 #define CMD_HASH_MASK STD_MI_OPCODE_MASK
642
643 static int init_hash_table(struct intel_engine_cs *engine,
644                            const struct drm_i915_cmd_table *cmd_tables,
645                            int cmd_table_count)
646 {
647         int i, j;
648
649         hash_init(engine->cmd_hash);
650
651         for (i = 0; i < cmd_table_count; i++) {
652                 const struct drm_i915_cmd_table *table = &cmd_tables[i];
653
654                 for (j = 0; j < table->count; j++) {
655                         const struct drm_i915_cmd_descriptor *desc =
656                                 &table->table[j];
657                         struct cmd_node *desc_node =
658                                 kmalloc(sizeof(*desc_node), GFP_KERNEL);
659
660                         if (!desc_node)
661                                 return -ENOMEM;
662
663                         desc_node->desc = desc;
664                         hash_add(engine->cmd_hash, &desc_node->node,
665                                  desc->cmd.value & CMD_HASH_MASK);
666                 }
667         }
668
669         return 0;
670 }
671
672 static void fini_hash_table(struct intel_engine_cs *engine)
673 {
674         struct hlist_node *tmp;
675         struct cmd_node *desc_node;
676         int i;
677
678         hash_for_each_safe(engine->cmd_hash, i, tmp, desc_node, node) {
679                 hash_del(&desc_node->node);
680                 kfree(desc_node);
681         }
682 }
683
684 /**
685  * i915_cmd_parser_init_ring() - set cmd parser related fields for a ringbuffer
686  * @ring: the ringbuffer to initialize
687  *
688  * Optionally initializes fields related to batch buffer command parsing in the
689  * struct intel_engine_cs based on whether the platform requires software
690  * command parsing.
691  *
692  * Return: non-zero if initialization fails
693  */
694 int i915_cmd_parser_init_ring(struct intel_engine_cs *engine)
695 {
696         const struct drm_i915_cmd_table *cmd_tables;
697         int cmd_table_count;
698         int ret;
699
700         if (!IS_GEN7(engine->dev))
701                 return 0;
702
703         switch (engine->id) {
704         case RCS:
705                 if (IS_HASWELL(engine->dev)) {
706                         cmd_tables = hsw_render_ring_cmds;
707                         cmd_table_count =
708                                 ARRAY_SIZE(hsw_render_ring_cmds);
709                 } else {
710                         cmd_tables = gen7_render_cmds;
711                         cmd_table_count = ARRAY_SIZE(gen7_render_cmds);
712                 }
713
714                 engine->reg_table = gen7_render_regs;
715                 engine->reg_count = ARRAY_SIZE(gen7_render_regs);
716
717                 if (IS_HASWELL(engine->dev)) {
718                         engine->master_reg_table = hsw_master_regs;
719                         engine->master_reg_count = ARRAY_SIZE(hsw_master_regs);
720                 } else {
721                         engine->master_reg_table = ivb_master_regs;
722                         engine->master_reg_count = ARRAY_SIZE(ivb_master_regs);
723                 }
724
725                 engine->get_cmd_length_mask = gen7_render_get_cmd_length_mask;
726                 break;
727         case VCS:
728                 cmd_tables = gen7_video_cmds;
729                 cmd_table_count = ARRAY_SIZE(gen7_video_cmds);
730                 engine->get_cmd_length_mask = gen7_bsd_get_cmd_length_mask;
731                 break;
732         case BCS:
733                 if (IS_HASWELL(engine->dev)) {
734                         cmd_tables = hsw_blt_ring_cmds;
735                         cmd_table_count = ARRAY_SIZE(hsw_blt_ring_cmds);
736                 } else {
737                         cmd_tables = gen7_blt_cmds;
738                         cmd_table_count = ARRAY_SIZE(gen7_blt_cmds);
739                 }
740
741                 engine->reg_table = gen7_blt_regs;
742                 engine->reg_count = ARRAY_SIZE(gen7_blt_regs);
743
744                 if (IS_HASWELL(engine->dev)) {
745                         engine->master_reg_table = hsw_master_regs;
746                         engine->master_reg_count = ARRAY_SIZE(hsw_master_regs);
747                 } else {
748                         engine->master_reg_table = ivb_master_regs;
749                         engine->master_reg_count = ARRAY_SIZE(ivb_master_regs);
750                 }
751
752                 engine->get_cmd_length_mask = gen7_blt_get_cmd_length_mask;
753                 break;
754         case VECS:
755                 cmd_tables = hsw_vebox_cmds;
756                 cmd_table_count = ARRAY_SIZE(hsw_vebox_cmds);
757                 /* VECS can use the same length_mask function as VCS */
758                 engine->get_cmd_length_mask = gen7_bsd_get_cmd_length_mask;
759                 break;
760         default:
761                 DRM_ERROR("CMD: cmd_parser_init with unknown ring: %d\n",
762                           engine->id);
763                 BUG();
764         }
765
766         BUG_ON(!validate_cmds_sorted(engine, cmd_tables, cmd_table_count));
767         BUG_ON(!validate_regs_sorted(engine));
768
769         WARN_ON(!hash_empty(engine->cmd_hash));
770
771         ret = init_hash_table(engine, cmd_tables, cmd_table_count);
772         if (ret) {
773                 DRM_ERROR("CMD: cmd_parser_init failed!\n");
774                 fini_hash_table(engine);
775                 return ret;
776         }
777
778         engine->needs_cmd_parser = true;
779
780         return 0;
781 }
782
783 /**
784  * i915_cmd_parser_fini_ring() - clean up cmd parser related fields
785  * @ring: the ringbuffer to clean up
786  *
787  * Releases any resources related to command parsing that may have been
788  * initialized for the specified ring.
789  */
790 void i915_cmd_parser_fini_ring(struct intel_engine_cs *engine)
791 {
792         if (!engine->needs_cmd_parser)
793                 return;
794
795         fini_hash_table(engine);
796 }
797
798 static const struct drm_i915_cmd_descriptor*
799 find_cmd_in_table(struct intel_engine_cs *engine,
800                   u32 cmd_header)
801 {
802         struct cmd_node *desc_node;
803
804         hash_for_each_possible(engine->cmd_hash, desc_node, node,
805                                cmd_header & CMD_HASH_MASK) {
806                 const struct drm_i915_cmd_descriptor *desc = desc_node->desc;
807                 u32 masked_cmd = desc->cmd.mask & cmd_header;
808                 u32 masked_value = desc->cmd.value & desc->cmd.mask;
809
810                 if (masked_cmd == masked_value)
811                         return desc;
812         }
813
814         return NULL;
815 }
816
817 /*
818  * Returns a pointer to a descriptor for the command specified by cmd_header.
819  *
820  * The caller must supply space for a default descriptor via the default_desc
821  * parameter. If no descriptor for the specified command exists in the ring's
822  * command parser tables, this function fills in default_desc based on the
823  * ring's default length encoding and returns default_desc.
824  */
825 static const struct drm_i915_cmd_descriptor*
826 find_cmd(struct intel_engine_cs *engine,
827          u32 cmd_header,
828          struct drm_i915_cmd_descriptor *default_desc)
829 {
830         const struct drm_i915_cmd_descriptor *desc;
831         u32 mask;
832
833         desc = find_cmd_in_table(engine, cmd_header);
834         if (desc)
835                 return desc;
836
837         mask = engine->get_cmd_length_mask(cmd_header);
838         if (!mask)
839                 return NULL;
840
841         BUG_ON(!default_desc);
842         default_desc->flags = CMD_DESC_SKIP;
843         default_desc->length.mask = mask;
844
845         return default_desc;
846 }
847
848 static const struct drm_i915_reg_descriptor *
849 find_reg(const struct drm_i915_reg_descriptor *table,
850          int count, u32 addr)
851 {
852         if (table) {
853                 int i;
854
855                 for (i = 0; i < count; i++) {
856                         if (i915_mmio_reg_offset(table[i].addr) == addr)
857                                 return &table[i];
858                 }
859         }
860
861         return NULL;
862 }
863
864 static u32 *vmap_batch(struct drm_i915_gem_object *obj,
865                        unsigned start, unsigned len)
866 {
867         int i;
868         void *addr = NULL;
869         struct sg_page_iter sg_iter;
870         int first_page = start >> PAGE_SHIFT;
871         int last_page = (len + start + 4095) >> PAGE_SHIFT;
872         int npages = last_page - first_page;
873         struct page **pages;
874
875         pages = drm_malloc_ab(npages, sizeof(*pages));
876         if (pages == NULL) {
877                 DRM_DEBUG_DRIVER("Failed to get space for pages\n");
878                 goto finish;
879         }
880
881         i = 0;
882         for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents, first_page) {
883                 pages[i++] = sg_page_iter_page(&sg_iter);
884                 if (i == npages)
885                         break;
886         }
887
888         addr = vmap(pages, i, 0, PAGE_KERNEL);
889         if (addr == NULL) {
890                 DRM_DEBUG_DRIVER("Failed to vmap pages\n");
891                 goto finish;
892         }
893
894 finish:
895         if (pages)
896                 drm_free_large(pages);
897         return (u32*)addr;
898 }
899
900 /* Returns a vmap'd pointer to dest_obj, which the caller must unmap */
901 static u32 *copy_batch(struct drm_i915_gem_object *dest_obj,
902                        struct drm_i915_gem_object *src_obj,
903                        u32 batch_start_offset,
904                        u32 batch_len)
905 {
906         int needs_clflush = 0;
907         void *src_base, *src;
908         void *dst = NULL;
909         int ret;
910
911         if (batch_len > dest_obj->base.size ||
912             batch_len + batch_start_offset > src_obj->base.size)
913                 return ERR_PTR(-E2BIG);
914
915         if (WARN_ON(dest_obj->pages_pin_count == 0))
916                 return ERR_PTR(-ENODEV);
917
918         ret = i915_gem_obj_prepare_shmem_read(src_obj, &needs_clflush);
919         if (ret) {
920                 DRM_DEBUG_DRIVER("CMD: failed to prepare shadow batch\n");
921                 return ERR_PTR(ret);
922         }
923
924         src_base = vmap_batch(src_obj, batch_start_offset, batch_len);
925         if (!src_base) {
926                 DRM_DEBUG_DRIVER("CMD: Failed to vmap batch\n");
927                 ret = -ENOMEM;
928                 goto unpin_src;
929         }
930
931         ret = i915_gem_object_set_to_cpu_domain(dest_obj, true);
932         if (ret) {
933                 DRM_DEBUG_DRIVER("CMD: Failed to set shadow batch to CPU\n");
934                 goto unmap_src;
935         }
936
937         dst = vmap_batch(dest_obj, 0, batch_len);
938         if (!dst) {
939                 DRM_DEBUG_DRIVER("CMD: Failed to vmap shadow batch\n");
940                 ret = -ENOMEM;
941                 goto unmap_src;
942         }
943
944         src = src_base + offset_in_page(batch_start_offset);
945         if (needs_clflush)
946                 drm_clflush_virt_range(src, batch_len);
947
948         memcpy(dst, src, batch_len);
949
950 unmap_src:
951         vunmap(src_base);
952 unpin_src:
953         i915_gem_object_unpin_pages(src_obj);
954
955         return ret ? ERR_PTR(ret) : dst;
956 }
957
958 /**
959  * i915_needs_cmd_parser() - should a given ring use software command parsing?
960  * @ring: the ring in question
961  *
962  * Only certain platforms require software batch buffer command parsing, and
963  * only when enabled via module parameter.
964  *
965  * Return: true if the ring requires software command parsing
966  */
967 bool i915_needs_cmd_parser(struct intel_engine_cs *engine)
968 {
969         if (!engine->needs_cmd_parser)
970                 return false;
971
972         if (!USES_PPGTT(engine->dev))
973                 return false;
974
975         return (i915.enable_cmd_parser == 1);
976 }
977
978 static bool check_cmd(const struct intel_engine_cs *engine,
979                       const struct drm_i915_cmd_descriptor *desc,
980                       const u32 *cmd, u32 length,
981                       const bool is_master,
982                       bool *oacontrol_set)
983 {
984         if (desc->flags & CMD_DESC_REJECT) {
985                 DRM_DEBUG_DRIVER("CMD: Rejected command: 0x%08X\n", *cmd);
986                 return false;
987         }
988
989         if ((desc->flags & CMD_DESC_MASTER) && !is_master) {
990                 DRM_DEBUG_DRIVER("CMD: Rejected master-only command: 0x%08X\n",
991                                  *cmd);
992                 return false;
993         }
994
995         if (desc->flags & CMD_DESC_REGISTER) {
996                 /*
997                  * Get the distance between individual register offset
998                  * fields if the command can perform more than one
999                  * access at a time.
1000                  */
1001                 const u32 step = desc->reg.step ? desc->reg.step : length;
1002                 u32 offset;
1003
1004                 for (offset = desc->reg.offset; offset < length;
1005                      offset += step) {
1006                         const u32 reg_addr = cmd[offset] & desc->reg.mask;
1007                         const struct drm_i915_reg_descriptor *reg =
1008                                 find_reg(engine->reg_table, engine->reg_count,
1009                                          reg_addr);
1010
1011                         if (!reg && is_master)
1012                                 reg = find_reg(engine->master_reg_table,
1013                                                engine->master_reg_count,
1014                                                reg_addr);
1015
1016                         if (!reg) {
1017                                 DRM_DEBUG_DRIVER("CMD: Rejected register 0x%08X in command: 0x%08X (ring=%d)\n",
1018                                                  reg_addr, *cmd, engine->id);
1019                                 return false;
1020                         }
1021
1022                         /*
1023                          * OACONTROL requires some special handling for
1024                          * writes. We want to make sure that any batch which
1025                          * enables OA also disables it before the end of the
1026                          * batch. The goal is to prevent one process from
1027                          * snooping on the perf data from another process. To do
1028                          * that, we need to check the value that will be written
1029                          * to the register. Hence, limit OACONTROL writes to
1030                          * only MI_LOAD_REGISTER_IMM commands.
1031                          */
1032                         if (reg_addr == i915_mmio_reg_offset(OACONTROL)) {
1033                                 if (desc->cmd.value == MI_LOAD_REGISTER_MEM) {
1034                                         DRM_DEBUG_DRIVER("CMD: Rejected LRM to OACONTROL\n");
1035                                         return false;
1036                                 }
1037
1038                                 if (desc->cmd.value == MI_LOAD_REGISTER_IMM(1))
1039                                         *oacontrol_set = (cmd[offset + 1] != 0);
1040                         }
1041
1042                         /*
1043                          * Check the value written to the register against the
1044                          * allowed mask/value pair given in the whitelist entry.
1045                          */
1046                         if (reg->mask) {
1047                                 if (desc->cmd.value == MI_LOAD_REGISTER_MEM) {
1048                                         DRM_DEBUG_DRIVER("CMD: Rejected LRM to masked register 0x%08X\n",
1049                                                          reg_addr);
1050                                         return false;
1051                                 }
1052
1053                                 if (desc->cmd.value == MI_LOAD_REGISTER_IMM(1) &&
1054                                     (offset + 2 > length ||
1055                                      (cmd[offset + 1] & reg->mask) != reg->value)) {
1056                                         DRM_DEBUG_DRIVER("CMD: Rejected LRI to masked register 0x%08X\n",
1057                                                          reg_addr);
1058                                         return false;
1059                                 }
1060                         }
1061                 }
1062         }
1063
1064         if (desc->flags & CMD_DESC_BITMASK) {
1065                 int i;
1066
1067                 for (i = 0; i < MAX_CMD_DESC_BITMASKS; i++) {
1068                         u32 dword;
1069
1070                         if (desc->bits[i].mask == 0)
1071                                 break;
1072
1073                         if (desc->bits[i].condition_mask != 0) {
1074                                 u32 offset =
1075                                         desc->bits[i].condition_offset;
1076                                 u32 condition = cmd[offset] &
1077                                         desc->bits[i].condition_mask;
1078
1079                                 if (condition == 0)
1080                                         continue;
1081                         }
1082
1083                         dword = cmd[desc->bits[i].offset] &
1084                                 desc->bits[i].mask;
1085
1086                         if (dword != desc->bits[i].expected) {
1087                                 DRM_DEBUG_DRIVER("CMD: Rejected command 0x%08X for bitmask 0x%08X (exp=0x%08X act=0x%08X) (ring=%d)\n",
1088                                                  *cmd,
1089                                                  desc->bits[i].mask,
1090                                                  desc->bits[i].expected,
1091                                                  dword, engine->id);
1092                                 return false;
1093                         }
1094                 }
1095         }
1096
1097         return true;
1098 }
1099
1100 #define LENGTH_BIAS 2
1101
1102 /**
1103  * i915_parse_cmds() - parse a submitted batch buffer for privilege violations
1104  * @ring: the ring on which the batch is to execute
1105  * @batch_obj: the batch buffer in question
1106  * @shadow_batch_obj: copy of the batch buffer in question
1107  * @batch_start_offset: byte offset in the batch at which execution starts
1108  * @batch_len: length of the commands in batch_obj
1109  * @is_master: is the submitting process the drm master?
1110  *
1111  * Parses the specified batch buffer looking for privilege violations as
1112  * described in the overview.
1113  *
1114  * Return: non-zero if the parser finds violations or otherwise fails; -EACCES
1115  * if the batch appears legal but should use hardware parsing
1116  */
1117 int i915_parse_cmds(struct intel_engine_cs *engine,
1118                     struct drm_i915_gem_object *batch_obj,
1119                     struct drm_i915_gem_object *shadow_batch_obj,
1120                     u32 batch_start_offset,
1121                     u32 batch_len,
1122                     bool is_master)
1123 {
1124         u32 *cmd, *batch_base, *batch_end;
1125         struct drm_i915_cmd_descriptor default_desc = { 0 };
1126         bool oacontrol_set = false; /* OACONTROL tracking. See check_cmd() */
1127         int ret = 0;
1128
1129         batch_base = copy_batch(shadow_batch_obj, batch_obj,
1130                                 batch_start_offset, batch_len);
1131         if (IS_ERR(batch_base)) {
1132                 DRM_DEBUG_DRIVER("CMD: Failed to copy batch\n");
1133                 return PTR_ERR(batch_base);
1134         }
1135
1136         /*
1137          * We use the batch length as size because the shadow object is as
1138          * large or larger and copy_batch() will write MI_NOPs to the extra
1139          * space. Parsing should be faster in some cases this way.
1140          */
1141         batch_end = batch_base + (batch_len / sizeof(*batch_end));
1142
1143         cmd = batch_base;
1144         while (cmd < batch_end) {
1145                 const struct drm_i915_cmd_descriptor *desc;
1146                 u32 length;
1147
1148                 if (*cmd == MI_BATCH_BUFFER_END)
1149                         break;
1150
1151                 desc = find_cmd(engine, *cmd, &default_desc);
1152                 if (!desc) {
1153                         DRM_DEBUG_DRIVER("CMD: Unrecognized command: 0x%08X\n",
1154                                          *cmd);
1155                         ret = -EINVAL;
1156                         break;
1157                 }
1158
1159                 /*
1160                  * If the batch buffer contains a chained batch, return an
1161                  * error that tells the caller to abort and dispatch the
1162                  * workload as a non-secure batch.
1163                  */
1164                 if (desc->cmd.value == MI_BATCH_BUFFER_START) {
1165                         ret = -EACCES;
1166                         break;
1167                 }
1168
1169                 if (desc->flags & CMD_DESC_FIXED)
1170                         length = desc->length.fixed;
1171                 else
1172                         length = ((*cmd & desc->length.mask) + LENGTH_BIAS);
1173
1174                 if ((batch_end - cmd) < length) {
1175                         DRM_DEBUG_DRIVER("CMD: Command length exceeds batch length: 0x%08X length=%u batchlen=%td\n",
1176                                          *cmd,
1177                                          length,
1178                                          batch_end - cmd);
1179                         ret = -EINVAL;
1180                         break;
1181                 }
1182
1183                 if (!check_cmd(engine, desc, cmd, length, is_master,
1184                                &oacontrol_set)) {
1185                         ret = -EINVAL;
1186                         break;
1187                 }
1188
1189                 cmd += length;
1190         }
1191
1192         if (oacontrol_set) {
1193                 DRM_DEBUG_DRIVER("CMD: batch set OACONTROL but did not clear it\n");
1194                 ret = -EINVAL;
1195         }
1196
1197         if (cmd >= batch_end) {
1198                 DRM_DEBUG_DRIVER("CMD: Got to the end of the buffer w/o a BBE cmd!\n");
1199                 ret = -EINVAL;
1200         }
1201
1202         vunmap(batch_base);
1203
1204         return ret;
1205 }
1206
1207 /**
1208  * i915_cmd_parser_get_version() - get the cmd parser version number
1209  *
1210  * The cmd parser maintains a simple increasing integer version number suitable
1211  * for passing to userspace clients to determine what operations are permitted.
1212  *
1213  * Return: the current version number of the cmd parser
1214  */
1215 int i915_cmd_parser_get_version(void)
1216 {
1217         /*
1218          * Command parser version history
1219          *
1220          * 1. Initial version. Checks batches and reports violations, but leaves
1221          *    hardware parsing enabled (so does not allow new use cases).
1222          * 2. Allow access to the MI_PREDICATE_SRC0 and
1223          *    MI_PREDICATE_SRC1 registers.
1224          * 3. Allow access to the GPGPU_THREADS_DISPATCHED register.
1225          * 4. L3 atomic chicken bits of HSW_SCRATCH1 and HSW_ROW_CHICKEN3.
1226          * 5. GPGPU dispatch compute indirect registers.
1227          */
1228         return 5;
1229 }