| /* |
| * Copyright © 2013 Intel Corporation |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a |
| * copy of this software and associated documentation files (the "Software"), |
| * to deal in the Software without restriction, including without limitation |
| * the rights to use, copy, modify, merge, publish, distribute, sublicense, |
| * and/or sell copies of the Software, and to permit persons to whom the |
| * Software is furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice (including the next |
| * paragraph) shall be included in all copies or substantial portions of the |
| * Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
| * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS |
| * IN THE SOFTWARE. |
| * |
| * Authors: |
| * Brad Volkin <bradley.d.volkin@intel.com> |
| * |
| */ |
| |
| #include "i915_drv.h" |
| |
| /** |
| * DOC: batch buffer command parser |
| * |
| * Motivation: |
| * Certain OpenGL features (e.g. transform feedback, performance monitoring) |
| * require userspace code to submit batches containing commands such as |
| * MI_LOAD_REGISTER_IMM to access various registers. Unfortunately, some |
| * generations of the hardware will noop these commands in "unsecure" batches |
| * (which includes all userspace batches submitted via i915) even though the |
| * commands may be safe and represent the intended programming model of the |
| * device. |
| * |
| * The software command parser is similar in operation to the command parsing |
| * done in hardware for unsecure batches. However, the software parser allows |
| * some operations that would be noop'd by hardware, if the parser determines |
| * the operation is safe, and submits the batch as "secure" to prevent hardware |
| * parsing. |
| * |
| * Threats: |
| * At a high level, the hardware (and software) checks attempt to prevent |
| * granting userspace undue privileges. There are three categories of privilege. |
| * |
| * First, commands which are explicitly defined as privileged or which should |
| * only be used by the kernel driver. The parser generally rejects such |
| * commands, though it may allow some from the drm master process. |
| * |
| * Second, commands which access registers. To support correct/enhanced |
| * userspace functionality, particularly certain OpenGL extensions, the parser |
| * provides a whitelist of registers which userspace may safely access (for both |
| * normal and drm master processes). |
| * |
| * Third, commands which access privileged memory (i.e. GGTT, HWS page, etc). |
| * The parser always rejects such commands. |
| * |
| * The majority of the problematic commands fall in the MI_* range, with only a |
| * few specific commands on each ring (e.g. PIPE_CONTROL and MI_FLUSH_DW). |
| * |
| * Implementation: |
| * Each ring maintains tables of commands and registers which the parser uses in |
| * scanning batch buffers submitted to that ring. |
| * |
| * Since the set of commands that the parser must check for is significantly |
| * smaller than the number of commands supported, the parser tables contain only |
| * those commands required by the parser. This generally works because command |
| * opcode ranges have standard command length encodings. So for commands that |
| * the parser does not need to check, it can easily skip them. This is |
| * implemented via a per-ring length decoding vfunc. |
| * |
| * Unfortunately, there are a number of commands that do not follow the standard |
| * length encoding for their opcode range, primarily amongst the MI_* commands. |
| * To handle this, the parser provides a way to define explicit "skip" entries |
| * in the per-ring command tables. |
| * |
| * Other command table entries map fairly directly to high level categories |
| * mentioned above: rejected, master-only, register whitelist. The parser |
| * implements a number of checks, including the privileged memory checks, via a |
| * general bitmasking mechanism. |
| */ |
| |
| #define STD_MI_OPCODE_MASK 0xFF800000 |
| #define STD_3D_OPCODE_MASK 0xFFFF0000 |
| #define STD_2D_OPCODE_MASK 0xFFC00000 |
| #define STD_MFX_OPCODE_MASK 0xFFFF0000 |
| |
| #define CMD(op, opm, f, lm, fl, ...) \ |
| { \ |
| .flags = (fl) | ((f) ? CMD_DESC_FIXED : 0), \ |
| .cmd = { (op), (opm) }, \ |
| .length = { (lm) }, \ |
| __VA_ARGS__ \ |
| } |
| |
| /* Convenience macros to compress the tables */ |
| #define SMI STD_MI_OPCODE_MASK |
| #define S3D STD_3D_OPCODE_MASK |
| #define S2D STD_2D_OPCODE_MASK |
| #define SMFX STD_MFX_OPCODE_MASK |
| #define F true |
| #define S CMD_DESC_SKIP |
| #define R CMD_DESC_REJECT |
| #define W CMD_DESC_REGISTER |
| #define B CMD_DESC_BITMASK |
| #define M CMD_DESC_MASTER |
| |
| /* Command Mask Fixed Len Action |
| ---------------------------------------------------------- */ |
| static const struct drm_i915_cmd_descriptor common_cmds[] = { |
| CMD( MI_NOOP, SMI, F, 1, S ), |
| CMD( MI_USER_INTERRUPT, SMI, F, 1, R ), |
| CMD( MI_WAIT_FOR_EVENT, SMI, F, 1, M ), |
| CMD( MI_ARB_CHECK, SMI, F, 1, S ), |
| CMD( MI_REPORT_HEAD, SMI, F, 1, S ), |
| CMD( MI_SUSPEND_FLUSH, SMI, F, 1, S ), |
| CMD( MI_SEMAPHORE_MBOX, SMI, !F, 0xFF, R ), |
| CMD( MI_STORE_DWORD_INDEX, SMI, !F, 0xFF, R ), |
| CMD( MI_LOAD_REGISTER_IMM(1), SMI, !F, 0xFF, W, |
| .reg = { .offset = 1, .mask = 0x007FFFFC, .step = 2 } ), |
| CMD( MI_STORE_REGISTER_MEM, SMI, F, 3, W | B, |
| .reg = { .offset = 1, .mask = 0x007FFFFC }, |
| .bits = {{ |
| .offset = 0, |
| .mask = MI_GLOBAL_GTT, |
| .expected = 0, |
| }}, ), |
| CMD( MI_LOAD_REGISTER_MEM, SMI, F, 3, W | B, |
| .reg = { .offset = 1, .mask = 0x007FFFFC }, |
| .bits = {{ |
| .offset = 0, |
| .mask = MI_GLOBAL_GTT, |
| .expected = 0, |
| }}, ), |
| /* |
| * MI_BATCH_BUFFER_START requires some special handling. It's not |
| * really a 'skip' action but it doesn't seem like it's worth adding |
| * a new action. See i915_parse_cmds(). |
| */ |
| CMD( MI_BATCH_BUFFER_START, SMI, !F, 0xFF, S ), |
| }; |
| |
| static const struct drm_i915_cmd_descriptor render_cmds[] = { |
| CMD( MI_FLUSH, SMI, F, 1, S ), |
| CMD( MI_ARB_ON_OFF, SMI, F, 1, R ), |
| CMD( MI_PREDICATE, SMI, F, 1, S ), |
| CMD( MI_TOPOLOGY_FILTER, SMI, F, 1, S ), |
| CMD( MI_SET_APPID, SMI, F, 1, S ), |
| CMD( MI_DISPLAY_FLIP, SMI, !F, 0xFF, R ), |
| CMD( MI_SET_CONTEXT, SMI, !F, 0xFF, R ), |
| CMD( MI_URB_CLEAR, SMI, !F, 0xFF, S ), |
| CMD( MI_STORE_DWORD_IMM, SMI, !F, 0x3F, B, |
| .bits = {{ |
| .offset = 0, |
| .mask = MI_GLOBAL_GTT, |
| .expected = 0, |
| }}, ), |
| CMD( MI_UPDATE_GTT, SMI, !F, 0xFF, R ), |
| CMD( MI_CLFLUSH, SMI, !F, 0x3FF, B, |
| .bits = {{ |
| .offset = 0, |
| .mask = MI_GLOBAL_GTT, |
| .expected = 0, |
| }}, ), |
| CMD( MI_REPORT_PERF_COUNT, SMI, !F, 0x3F, B, |
| .bits = {{ |
| .offset = 1, |
| .mask = MI_REPORT_PERF_COUNT_GGTT, |
| .expected = 0, |
| }}, ), |
| CMD( MI_CONDITIONAL_BATCH_BUFFER_END, SMI, !F, 0xFF, B, |
| .bits = {{ |
| .offset = 0, |
| .mask = MI_GLOBAL_GTT, |
| .expected = 0, |
| }}, ), |
| CMD( GFX_OP_3DSTATE_VF_STATISTICS, S3D, F, 1, S ), |
| CMD( PIPELINE_SELECT, S3D, F, 1, S ), |
| CMD( MEDIA_VFE_STATE, S3D, !F, 0xFFFF, B, |
| .bits = {{ |
| .offset = 2, |
| .mask = MEDIA_VFE_STATE_MMIO_ACCESS_MASK, |
| .expected = 0, |
| }}, ), |
| CMD( GPGPU_OBJECT, S3D, !F, 0xFF, S ), |
| CMD( GPGPU_WALKER, S3D, !F, 0xFF, S ), |
| CMD( GFX_OP_3DSTATE_SO_DECL_LIST, S3D, !F, 0x1FF, S ), |
| CMD( GFX_OP_PIPE_CONTROL(5), S3D, !F, 0xFF, B, |
| .bits = {{ |
| .offset = 1, |
| .mask = (PIPE_CONTROL_MMIO_WRITE | PIPE_CONTROL_NOTIFY), |
| .expected = 0, |
| }, |
| { |
| .offset = 1, |
| .mask = (PIPE_CONTROL_GLOBAL_GTT_IVB | |
| PIPE_CONTROL_STORE_DATA_INDEX), |
| .expected = 0, |
| .condition_offset = 1, |
| .condition_mask = PIPE_CONTROL_POST_SYNC_OP_MASK, |
| }}, ), |
| }; |
| |
| static const struct drm_i915_cmd_descriptor hsw_render_cmds[] = { |
| CMD( MI_SET_PREDICATE, SMI, F, 1, S ), |
| CMD( MI_RS_CONTROL, SMI, F, 1, S ), |
| CMD( MI_URB_ATOMIC_ALLOC, SMI, F, 1, S ), |
| CMD( MI_SET_APPID, SMI, F, 1, S ), |
| CMD( MI_RS_CONTEXT, SMI, F, 1, S ), |
| CMD( MI_LOAD_SCAN_LINES_INCL, SMI, !F, 0x3F, M ), |
| CMD( MI_LOAD_SCAN_LINES_EXCL, SMI, !F, 0x3F, R ), |
| CMD( MI_LOAD_REGISTER_REG, SMI, !F, 0xFF, R ), |
| CMD( MI_RS_STORE_DATA_IMM, SMI, !F, 0xFF, S ), |
| CMD( MI_LOAD_URB_MEM, SMI, !F, 0xFF, S ), |
| CMD( MI_STORE_URB_MEM, SMI, !F, 0xFF, S ), |
| CMD( GFX_OP_3DSTATE_DX9_CONSTANTF_VS, S3D, !F, 0x7FF, S ), |
| CMD( GFX_OP_3DSTATE_DX9_CONSTANTF_PS, S3D, !F, 0x7FF, S ), |
| |
| CMD( GFX_OP_3DSTATE_BINDING_TABLE_EDIT_VS, S3D, !F, 0x1FF, S ), |
| CMD( GFX_OP_3DSTATE_BINDING_TABLE_EDIT_GS, S3D, !F, 0x1FF, S ), |
| CMD( GFX_OP_3DSTATE_BINDING_TABLE_EDIT_HS, S3D, !F, 0x1FF, S ), |
| CMD( GFX_OP_3DSTATE_BINDING_TABLE_EDIT_DS, S3D, !F, 0x1FF, S ), |
| CMD( GFX_OP_3DSTATE_BINDING_TABLE_EDIT_PS, S3D, !F, 0x1FF, S ), |
| }; |
| |
| static const struct drm_i915_cmd_descriptor video_cmds[] = { |
| CMD( MI_ARB_ON_OFF, SMI, F, 1, R ), |
| CMD( MI_SET_APPID, SMI, F, 1, S ), |
| CMD( MI_STORE_DWORD_IMM, SMI, !F, 0xFF, B, |
| .bits = {{ |
| .offset = 0, |
| .mask = MI_GLOBAL_GTT, |
| .expected = 0, |
| }}, ), |
| CMD( MI_UPDATE_GTT, SMI, !F, 0x3F, R ), |
| CMD( MI_FLUSH_DW, SMI, !F, 0x3F, B, |
| .bits = {{ |
| .offset = 0, |
| .mask = MI_FLUSH_DW_NOTIFY, |
| .expected = 0, |
| }, |
| { |
| .offset = 1, |
| .mask = MI_FLUSH_DW_USE_GTT, |
| .expected = 0, |
| .condition_offset = 0, |
| .condition_mask = MI_FLUSH_DW_OP_MASK, |
| }, |
| { |
| .offset = 0, |
| .mask = MI_FLUSH_DW_STORE_INDEX, |
| .expected = 0, |
| .condition_offset = 0, |
| .condition_mask = MI_FLUSH_DW_OP_MASK, |
| }}, ), |
| CMD( MI_CONDITIONAL_BATCH_BUFFER_END, SMI, !F, 0xFF, B, |
| .bits = {{ |
| .offset = 0, |
| .mask = MI_GLOBAL_GTT, |
| .expected = 0, |
| }}, ), |
| /* |
| * MFX_WAIT doesn't fit the way we handle length for most commands. |
| * It has a length field but it uses a non-standard length bias. |
| * It is always 1 dword though, so just treat it as fixed length. |
| */ |
| CMD( MFX_WAIT, SMFX, F, 1, S ), |
| }; |
| |
| static const struct drm_i915_cmd_descriptor vecs_cmds[] = { |
| CMD( MI_ARB_ON_OFF, SMI, F, 1, R ), |
| CMD( MI_SET_APPID, SMI, F, 1, S ), |
| CMD( MI_STORE_DWORD_IMM, SMI, !F, 0xFF, B, |
| .bits = {{ |
| .offset = 0, |
| .mask = MI_GLOBAL_GTT, |
| .expected = 0, |
| }}, ), |
| CMD( MI_UPDATE_GTT, SMI, !F, 0x3F, R ), |
| CMD( MI_FLUSH_DW, SMI, !F, 0x3F, B, |
| .bits = {{ |
| .offset = 0, |
| .mask = MI_FLUSH_DW_NOTIFY, |
| .expected = 0, |
| }, |
| { |
| .offset = 1, |
| .mask = MI_FLUSH_DW_USE_GTT, |
| .expected = 0, |
| .condition_offset = 0, |
| .condition_mask = MI_FLUSH_DW_OP_MASK, |
| }, |
| { |
| .offset = 0, |
| .mask = MI_FLUSH_DW_STORE_INDEX, |
| .expected = 0, |
| .condition_offset = 0, |
| .condition_mask = MI_FLUSH_DW_OP_MASK, |
| }}, ), |
| CMD( MI_CONDITIONAL_BATCH_BUFFER_END, SMI, !F, 0xFF, B, |
| .bits = {{ |
| .offset = 0, |
| .mask = MI_GLOBAL_GTT, |
| .expected = 0, |
| }}, ), |
| }; |
| |
| static const struct drm_i915_cmd_descriptor blt_cmds[] = { |
| CMD( MI_DISPLAY_FLIP, SMI, !F, 0xFF, R ), |
| CMD( MI_STORE_DWORD_IMM, SMI, !F, 0x3FF, B, |
| .bits = {{ |
| .offset = 0, |
| .mask = MI_GLOBAL_GTT, |
| .expected = 0, |
| }}, ), |
| CMD( MI_UPDATE_GTT, SMI, !F, 0x3F, R ), |
| CMD( MI_FLUSH_DW, SMI, !F, 0x3F, B, |
| .bits = {{ |
| .offset = 0, |
| .mask = MI_FLUSH_DW_NOTIFY, |
| .expected = 0, |
| }, |
| { |
| .offset = 1, |
| .mask = MI_FLUSH_DW_USE_GTT, |
| .expected = 0, |
| .condition_offset = 0, |
| .condition_mask = MI_FLUSH_DW_OP_MASK, |
| }, |
| { |
| .offset = 0, |
| .mask = MI_FLUSH_DW_STORE_INDEX, |
| .expected = 0, |
| .condition_offset = 0, |
| .condition_mask = MI_FLUSH_DW_OP_MASK, |
| }}, ), |
| CMD( COLOR_BLT, S2D, !F, 0x3F, S ), |
| CMD( SRC_COPY_BLT, S2D, !F, 0x3F, S ), |
| }; |
| |
| static const struct drm_i915_cmd_descriptor hsw_blt_cmds[] = { |
| CMD( MI_LOAD_SCAN_LINES_INCL, SMI, !F, 0x3F, M ), |
| CMD( MI_LOAD_SCAN_LINES_EXCL, SMI, !F, 0x3F, R ), |
| }; |
| |
| #undef CMD |
| #undef SMI |
| #undef S3D |
| #undef S2D |
| #undef SMFX |
| #undef F |
| #undef S |
| #undef R |
| #undef W |
| #undef B |
| #undef M |
| |
| static const struct drm_i915_cmd_table gen7_render_cmds[] = { |
| { common_cmds, ARRAY_SIZE(common_cmds) }, |
| { render_cmds, ARRAY_SIZE(render_cmds) }, |
| }; |
| |
| static const struct drm_i915_cmd_table hsw_render_ring_cmds[] = { |
| { common_cmds, ARRAY_SIZE(common_cmds) }, |
| { render_cmds, ARRAY_SIZE(render_cmds) }, |
| { hsw_render_cmds, ARRAY_SIZE(hsw_render_cmds) }, |
| }; |
| |
| static const struct drm_i915_cmd_table gen7_video_cmds[] = { |
| { common_cmds, ARRAY_SIZE(common_cmds) }, |
| { video_cmds, ARRAY_SIZE(video_cmds) }, |
| }; |
| |
| static const struct drm_i915_cmd_table hsw_vebox_cmds[] = { |
| { common_cmds, ARRAY_SIZE(common_cmds) }, |
| { vecs_cmds, ARRAY_SIZE(vecs_cmds) }, |
| }; |
| |
| static const struct drm_i915_cmd_table gen7_blt_cmds[] = { |
| { common_cmds, ARRAY_SIZE(common_cmds) }, |
| { blt_cmds, ARRAY_SIZE(blt_cmds) }, |
| }; |
| |
| static const struct drm_i915_cmd_table hsw_blt_ring_cmds[] = { |
| { common_cmds, ARRAY_SIZE(common_cmds) }, |
| { blt_cmds, ARRAY_SIZE(blt_cmds) }, |
| { hsw_blt_cmds, ARRAY_SIZE(hsw_blt_cmds) }, |
| }; |
| |
| /* |
| * Register whitelists, sorted by increasing register offset. |
| */ |
| |
| /* |
| * An individual whitelist entry granting access to register addr. If |
| * mask is non-zero the argument of immediate register writes will be |
| * AND-ed with mask, and the command will be rejected if the result |
| * doesn't match value. |
| * |
| * Registers with non-zero mask are only allowed to be written using |
| * LRI. |
| */ |
| struct drm_i915_reg_descriptor { |
| u32 addr; |
| u32 mask; |
| u32 value; |
| }; |
| |
| /* Convenience macro for adding 32-bit registers. */ |
| #define REG32(address, ...) \ |
| { .addr = address, __VA_ARGS__ } |
| |
| /* |
| * Convenience macro for adding 64-bit registers. |
| * |
| * Some registers that userspace accesses are 64 bits. The register |
| * access commands only allow 32-bit accesses. Hence, we have to include |
| * entries for both halves of the 64-bit registers. |
| */ |
| #define REG64(addr) \ |
| REG32(addr), REG32(addr + sizeof(u32)) |
| |
| static const struct drm_i915_reg_descriptor gen7_render_regs[] = { |
| REG64(GPGPU_THREADS_DISPATCHED), |
| REG64(HS_INVOCATION_COUNT), |
| REG64(DS_INVOCATION_COUNT), |
| REG64(IA_VERTICES_COUNT), |
| REG64(IA_PRIMITIVES_COUNT), |
| REG64(VS_INVOCATION_COUNT), |
| REG64(GS_INVOCATION_COUNT), |
| REG64(GS_PRIMITIVES_COUNT), |
| REG64(CL_INVOCATION_COUNT), |
| REG64(CL_PRIMITIVES_COUNT), |
| REG64(PS_INVOCATION_COUNT), |
| REG64(PS_DEPTH_COUNT), |
| REG32(OACONTROL), /* Only allowed for LRI and SRM. See below. */ |
| REG64(MI_PREDICATE_SRC0), |
| REG64(MI_PREDICATE_SRC1), |
| REG32(GEN7_3DPRIM_END_OFFSET), |
| REG32(GEN7_3DPRIM_START_VERTEX), |
| REG32(GEN7_3DPRIM_VERTEX_COUNT), |
| REG32(GEN7_3DPRIM_INSTANCE_COUNT), |
| REG32(GEN7_3DPRIM_START_INSTANCE), |
| REG32(GEN7_3DPRIM_BASE_VERTEX), |
| REG32(GEN7_GPGPU_DISPATCHDIMX), |
| REG32(GEN7_GPGPU_DISPATCHDIMY), |
| REG32(GEN7_GPGPU_DISPATCHDIMZ), |
| REG64(GEN7_SO_NUM_PRIMS_WRITTEN(0)), |
| REG64(GEN7_SO_NUM_PRIMS_WRITTEN(1)), |
| REG64(GEN7_SO_NUM_PRIMS_WRITTEN(2)), |
| REG64(GEN7_SO_NUM_PRIMS_WRITTEN(3)), |
| REG64(GEN7_SO_PRIM_STORAGE_NEEDED(0)), |
| REG64(GEN7_SO_PRIM_STORAGE_NEEDED(1)), |
| REG64(GEN7_SO_PRIM_STORAGE_NEEDED(2)), |
| REG64(GEN7_SO_PRIM_STORAGE_NEEDED(3)), |
| REG32(GEN7_SO_WRITE_OFFSET(0)), |
| REG32(GEN7_SO_WRITE_OFFSET(1)), |
| REG32(GEN7_SO_WRITE_OFFSET(2)), |
| REG32(GEN7_SO_WRITE_OFFSET(3)), |
| REG32(GEN7_L3SQCREG1), |
| REG32(GEN7_L3CNTLREG2), |
| REG32(GEN7_L3CNTLREG3), |
| REG32(HSW_SCRATCH1, |
| .mask = ~HSW_SCRATCH1_L3_DATA_ATOMICS_DISABLE, |
| .value = 0), |
| REG32(HSW_ROW_CHICKEN3, |
| .mask = ~(HSW_ROW_CHICKEN3_L3_GLOBAL_ATOMICS_DISABLE << 16 | |
| HSW_ROW_CHICKEN3_L3_GLOBAL_ATOMICS_DISABLE), |
| .value = 0), |
| }; |
| |
| static const struct drm_i915_reg_descriptor gen7_blt_regs[] = { |
| REG32(BCS_SWCTRL), |
| }; |
| |
| static const struct drm_i915_reg_descriptor ivb_master_regs[] = { |
| REG32(FORCEWAKE_MT), |
| REG32(DERRMR), |
| REG32(GEN7_PIPE_DE_LOAD_SL(PIPE_A)), |
| REG32(GEN7_PIPE_DE_LOAD_SL(PIPE_B)), |
| REG32(GEN7_PIPE_DE_LOAD_SL(PIPE_C)), |
| }; |
| |
| static const struct drm_i915_reg_descriptor hsw_master_regs[] = { |
| REG32(FORCEWAKE_MT), |
| REG32(DERRMR), |
| }; |
| |
| #undef REG64 |
| #undef REG32 |
| |
| static u32 gen7_render_get_cmd_length_mask(u32 cmd_header) |
| { |
| u32 client = (cmd_header & INSTR_CLIENT_MASK) >> INSTR_CLIENT_SHIFT; |
| u32 subclient = |
| (cmd_header & INSTR_SUBCLIENT_MASK) >> INSTR_SUBCLIENT_SHIFT; |
| |
| if (client == INSTR_MI_CLIENT) |
| return 0x3F; |
| else if (client == INSTR_RC_CLIENT) { |
| if (subclient == INSTR_MEDIA_SUBCLIENT) |
| return 0xFFFF; |
| else |
| return 0xFF; |
| } |
| |
| DRM_DEBUG_DRIVER("CMD: Abnormal rcs cmd length! 0x%08X\n", cmd_header); |
| return 0; |
| } |
| |
| static u32 gen7_bsd_get_cmd_length_mask(u32 cmd_header) |
| { |
| u32 client = (cmd_header & INSTR_CLIENT_MASK) >> INSTR_CLIENT_SHIFT; |
| u32 subclient = |
| (cmd_header & INSTR_SUBCLIENT_MASK) >> INSTR_SUBCLIENT_SHIFT; |
| u32 op = (cmd_header & INSTR_26_TO_24_MASK) >> INSTR_26_TO_24_SHIFT; |
| |
| if (client == INSTR_MI_CLIENT) |
| return 0x3F; |
| else if (client == INSTR_RC_CLIENT) { |
| if (subclient == INSTR_MEDIA_SUBCLIENT) { |
| if (op == 6) |
| return 0xFFFF; |
| else |
| return 0xFFF; |
| } else |
| return 0xFF; |
| } |
| |
| DRM_DEBUG_DRIVER("CMD: Abnormal bsd cmd length! 0x%08X\n", cmd_header); |
| return 0; |
| } |
| |
| static u32 gen7_blt_get_cmd_length_mask(u32 cmd_header) |
| { |
| u32 client = (cmd_header & INSTR_CLIENT_MASK) >> INSTR_CLIENT_SHIFT; |
| |
| if (client == INSTR_MI_CLIENT) |
| return 0x3F; |
| else if (client == INSTR_BC_CLIENT) |
| return 0xFF; |
| |
| DRM_DEBUG_DRIVER("CMD: Abnormal blt cmd length! 0x%08X\n", cmd_header); |
| return 0; |
| } |
| |
| static bool validate_cmds_sorted(struct intel_engine_cs *ring, |
| const struct drm_i915_cmd_table *cmd_tables, |
| int cmd_table_count) |
| { |
| int i; |
| bool ret = true; |
| |
| if (!cmd_tables || cmd_table_count == 0) |
| return true; |
| |
| for (i = 0; i < cmd_table_count; i++) { |
| const struct drm_i915_cmd_table *table = &cmd_tables[i]; |
| u32 previous = 0; |
| int j; |
| |
| for (j = 0; j < table->count; j++) { |
| const struct drm_i915_cmd_descriptor *desc = |
| &table->table[j]; |
| u32 curr = desc->cmd.value & desc->cmd.mask; |
| |
| if (curr < previous) { |
| DRM_ERROR("CMD: table not sorted ring=%d table=%d entry=%d cmd=0x%08X prev=0x%08X\n", |
| ring->id, i, j, curr, previous); |
| ret = false; |
| } |
| |
| previous = curr; |
| } |
| } |
| |
| return ret; |
| } |
| |
| static bool check_sorted(int ring_id, |
| const struct drm_i915_reg_descriptor *reg_table, |
| int reg_count) |
| { |
| int i; |
| u32 previous = 0; |
| bool ret = true; |
| |
| for (i = 0; i < reg_count; i++) { |
| u32 curr = reg_table[i].addr; |
| |
| if (curr < previous) { |
| DRM_ERROR("CMD: table not sorted ring=%d entry=%d reg=0x%08X prev=0x%08X\n", |
| ring_id, i, curr, previous); |
| ret = false; |
| } |
| |
| previous = curr; |
| } |
| |
| return ret; |
| } |
| |
| static bool validate_regs_sorted(struct intel_engine_cs *ring) |
| { |
| return check_sorted(ring->id, ring->reg_table, ring->reg_count) && |
| check_sorted(ring->id, ring->master_reg_table, |
| ring->master_reg_count); |
| } |
| |
| struct cmd_node { |
| const struct drm_i915_cmd_descriptor *desc; |
| struct hlist_node node; |
| }; |
| |
| /* |
| * Different command ranges have different numbers of bits for the opcode. For |
| * example, MI commands use bits 31:23 while 3D commands use bits 31:16. The |
| * problem is that, for example, MI commands use bits 22:16 for other fields |
| * such as GGTT vs PPGTT bits. If we include those bits in the mask then when |
| * we mask a command from a batch it could hash to the wrong bucket due to |
| * non-opcode bits being set. But if we don't include those bits, some 3D |
| * commands may hash to the same bucket due to not including opcode bits that |
| * make the command unique. For now, we will risk hashing to the same bucket. |
| * |
| * If we attempt to generate a perfect hash, we should be able to look at bits |
| * 31:29 of a command from a batch buffer and use the full mask for that |
| * client. The existing INSTR_CLIENT_MASK/SHIFT defines can be used for this. |
| */ |
| #define CMD_HASH_MASK STD_MI_OPCODE_MASK |
| |
| static int init_hash_table(struct intel_engine_cs *ring, |
| const struct drm_i915_cmd_table *cmd_tables, |
| int cmd_table_count) |
| { |
| int i, j; |
| |
| hash_init(ring->cmd_hash); |
| |
| for (i = 0; i < cmd_table_count; i++) { |
| const struct drm_i915_cmd_table *table = &cmd_tables[i]; |
| |
| for (j = 0; j < table->count; j++) { |
| const struct drm_i915_cmd_descriptor *desc = |
| &table->table[j]; |
| struct cmd_node *desc_node = |
| kmalloc(sizeof(*desc_node), GFP_KERNEL); |
| |
| if (!desc_node) |
| return -ENOMEM; |
| |
| desc_node->desc = desc; |
| hash_add(ring->cmd_hash, &desc_node->node, |
| desc->cmd.value & CMD_HASH_MASK); |
| } |
| } |
| |
| return 0; |
| } |
| |
| static void fini_hash_table(struct intel_engine_cs *ring) |
| { |
| struct hlist_node *tmp; |
| struct cmd_node *desc_node; |
| int i; |
| |
| hash_for_each_safe(ring->cmd_hash, i, tmp, desc_node, node) { |
| hash_del(&desc_node->node); |
| kfree(desc_node); |
| } |
| } |
| |
| /** |
| * i915_cmd_parser_init_ring() - set cmd parser related fields for a ringbuffer |
| * @ring: the ringbuffer to initialize |
| * |
| * Optionally initializes fields related to batch buffer command parsing in the |
| * struct intel_engine_cs based on whether the platform requires software |
| * command parsing. |
| * |
| * Return: non-zero if initialization fails |
| */ |
| int i915_cmd_parser_init_ring(struct intel_engine_cs *ring) |
| { |
| const struct drm_i915_cmd_table *cmd_tables; |
| int cmd_table_count; |
| int ret; |
| |
| if (!IS_GEN7(ring->dev)) |
| return 0; |
| |
| switch (ring->id) { |
| case RCS: |
| if (IS_HASWELL(ring->dev)) { |
| cmd_tables = hsw_render_ring_cmds; |
| cmd_table_count = |
| ARRAY_SIZE(hsw_render_ring_cmds); |
| } else { |
| cmd_tables = gen7_render_cmds; |
| cmd_table_count = ARRAY_SIZE(gen7_render_cmds); |
| } |
| |
| ring->reg_table = gen7_render_regs; |
| ring->reg_count = ARRAY_SIZE(gen7_render_regs); |
| |
| if (IS_HASWELL(ring->dev)) { |
| ring->master_reg_table = hsw_master_regs; |
| ring->master_reg_count = ARRAY_SIZE(hsw_master_regs); |
| } else { |
| ring->master_reg_table = ivb_master_regs; |
| ring->master_reg_count = ARRAY_SIZE(ivb_master_regs); |
| } |
| |
| ring->get_cmd_length_mask = gen7_render_get_cmd_length_mask; |
| break; |
| case VCS: |
| cmd_tables = gen7_video_cmds; |
| cmd_table_count = ARRAY_SIZE(gen7_video_cmds); |
| ring->get_cmd_length_mask = gen7_bsd_get_cmd_length_mask; |
| break; |
| case BCS: |
| if (IS_HASWELL(ring->dev)) { |
| cmd_tables = hsw_blt_ring_cmds; |
| cmd_table_count = ARRAY_SIZE(hsw_blt_ring_cmds); |
| } else { |
| cmd_tables = gen7_blt_cmds; |
| cmd_table_count = ARRAY_SIZE(gen7_blt_cmds); |
| } |
| |
| ring->reg_table = gen7_blt_regs; |
| ring->reg_count = ARRAY_SIZE(gen7_blt_regs); |
| |
| if (IS_HASWELL(ring->dev)) { |
| ring->master_reg_table = hsw_master_regs; |
| ring->master_reg_count = ARRAY_SIZE(hsw_master_regs); |
| } else { |
| ring->master_reg_table = ivb_master_regs; |
| ring->master_reg_count = ARRAY_SIZE(ivb_master_regs); |
| } |
| |
| ring->get_cmd_length_mask = gen7_blt_get_cmd_length_mask; |
| break; |
| case VECS: |
| cmd_tables = hsw_vebox_cmds; |
| cmd_table_count = ARRAY_SIZE(hsw_vebox_cmds); |
| /* VECS can use the same length_mask function as VCS */ |
| ring->get_cmd_length_mask = gen7_bsd_get_cmd_length_mask; |
| break; |
| default: |
| DRM_ERROR("CMD: cmd_parser_init with unknown ring: %d\n", |
| ring->id); |
| BUG(); |
| } |
| |
| BUG_ON(!validate_cmds_sorted(ring, cmd_tables, cmd_table_count)); |
| BUG_ON(!validate_regs_sorted(ring)); |
| |
| WARN_ON(!hash_empty(ring->cmd_hash)); |
| |
| ret = init_hash_table(ring, cmd_tables, cmd_table_count); |
| if (ret) { |
| DRM_ERROR("CMD: cmd_parser_init failed!\n"); |
| fini_hash_table(ring); |
| return ret; |
| } |
| |
| ring->needs_cmd_parser = true; |
| |
| return 0; |
| } |
| |
| /** |
| * i915_cmd_parser_fini_ring() - clean up cmd parser related fields |
| * @ring: the ringbuffer to clean up |
| * |
| * Releases any resources related to command parsing that may have been |
| * initialized for the specified ring. |
| */ |
| void i915_cmd_parser_fini_ring(struct intel_engine_cs *ring) |
| { |
| if (!ring->needs_cmd_parser) |
| return; |
| |
| fini_hash_table(ring); |
| } |
| |
| static const struct drm_i915_cmd_descriptor* |
| find_cmd_in_table(struct intel_engine_cs *ring, |
| u32 cmd_header) |
| { |
| struct cmd_node *desc_node; |
| |
| hash_for_each_possible(ring->cmd_hash, desc_node, node, |
| cmd_header & CMD_HASH_MASK) { |
| const struct drm_i915_cmd_descriptor *desc = desc_node->desc; |
| u32 masked_cmd = desc->cmd.mask & cmd_header; |
| u32 masked_value = desc->cmd.value & desc->cmd.mask; |
| |
| if (masked_cmd == masked_value) |
| return desc; |
| } |
| |
| return NULL; |
| } |
| |
| /* |
| * Returns a pointer to a descriptor for the command specified by cmd_header. |
| * |
| * The caller must supply space for a default descriptor via the default_desc |
| * parameter. If no descriptor for the specified command exists in the ring's |
| * command parser tables, this function fills in default_desc based on the |
| * ring's default length encoding and returns default_desc. |
| */ |
| static const struct drm_i915_cmd_descriptor* |
| find_cmd(struct intel_engine_cs *ring, |
| u32 cmd_header, |
| struct drm_i915_cmd_descriptor *default_desc) |
| { |
| const struct drm_i915_cmd_descriptor *desc; |
| u32 mask; |
| |
| desc = find_cmd_in_table(ring, cmd_header); |
| if (desc) |
| return desc; |
| |
| mask = ring->get_cmd_length_mask(cmd_header); |
| if (!mask) |
| return NULL; |
| |
| BUG_ON(!default_desc); |
| default_desc->flags = CMD_DESC_SKIP; |
| default_desc->length.mask = mask; |
| |
| return default_desc; |
| } |
| |
| static const struct drm_i915_reg_descriptor * |
| find_reg(const struct drm_i915_reg_descriptor *table, |
| int count, u32 addr) |
| { |
| if (table) { |
| int i; |
| |
| for (i = 0; i < count; i++) { |
| if (table[i].addr == addr) |
| return &table[i]; |
| } |
| } |
| |
| return NULL; |
| } |
| |
| static u32 *vmap_batch(struct drm_i915_gem_object *obj, |
| unsigned start, unsigned len) |
| { |
| int i; |
| void *addr = NULL; |
| struct sg_page_iter sg_iter; |
| int first_page = start >> PAGE_SHIFT; |
| int last_page = (len + start + 4095) >> PAGE_SHIFT; |
| int npages = last_page - first_page; |
| struct page **pages; |
| |
| pages = drm_malloc_ab(npages, sizeof(*pages)); |
| if (pages == NULL) { |
| DRM_DEBUG_DRIVER("Failed to get space for pages\n"); |
| goto finish; |
| } |
| |
| i = 0; |
| for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents, first_page) { |
| pages[i++] = sg_page_iter_page(&sg_iter); |
| if (i == npages) |
| break; |
| } |
| |
| addr = vmap(pages, i, 0, PAGE_KERNEL); |
| if (addr == NULL) { |
| DRM_DEBUG_DRIVER("Failed to vmap pages\n"); |
| goto finish; |
| } |
| |
| finish: |
| if (pages) |
| drm_free_large(pages); |
| return (u32*)addr; |
| } |
| |
| /* Returns a vmap'd pointer to dest_obj, which the caller must unmap */ |
| static u32 *copy_batch(struct drm_i915_gem_object *dest_obj, |
| struct drm_i915_gem_object *src_obj, |
| u32 batch_start_offset, |
| u32 batch_len) |
| { |
| int needs_clflush = 0; |
| void *src_base, *src; |
| void *dst = NULL; |
| int ret; |
| |
| if (batch_len > dest_obj->base.size || |
| batch_len + batch_start_offset > src_obj->base.size) |
| return ERR_PTR(-E2BIG); |
| |
| if (WARN_ON(dest_obj->pages_pin_count == 0)) |
| return ERR_PTR(-ENODEV); |
| |
| ret = i915_gem_obj_prepare_shmem_read(src_obj, &needs_clflush); |
| if (ret) { |
| DRM_DEBUG_DRIVER("CMD: failed to prepare shadow batch\n"); |
| return ERR_PTR(ret); |
| } |
| |
| src_base = vmap_batch(src_obj, batch_start_offset, batch_len); |
| if (!src_base) { |
| DRM_DEBUG_DRIVER("CMD: Failed to vmap batch\n"); |
| ret = -ENOMEM; |
| goto unpin_src; |
| } |
| |
| ret = i915_gem_object_set_to_cpu_domain(dest_obj, true); |
| if (ret) { |
| DRM_DEBUG_DRIVER("CMD: Failed to set shadow batch to CPU\n"); |
| goto unmap_src; |
| } |
| |
| dst = vmap_batch(dest_obj, 0, batch_len); |
| if (!dst) { |
| DRM_DEBUG_DRIVER("CMD: Failed to vmap shadow batch\n"); |
| ret = -ENOMEM; |
| goto unmap_src; |
| } |
| |
| src = src_base + offset_in_page(batch_start_offset); |
| if (needs_clflush) |
| drm_clflush_virt_range(src, batch_len); |
| |
| memcpy(dst, src, batch_len); |
| |
| unmap_src: |
| vunmap(src_base); |
| unpin_src: |
| i915_gem_object_unpin_pages(src_obj); |
| |
| return ret ? ERR_PTR(ret) : dst; |
| } |
| |
| /** |
| * i915_needs_cmd_parser() - should a given ring use software command parsing? |
| * @ring: the ring in question |
| * |
| * Only certain platforms require software batch buffer command parsing, and |
| * only when enabled via module parameter. |
| * |
| * Return: true if the ring requires software command parsing |
| */ |
| bool i915_needs_cmd_parser(struct intel_engine_cs *ring) |
| { |
| if (!ring->needs_cmd_parser) |
| return false; |
| |
| if (!USES_PPGTT(ring->dev)) |
| return false; |
| |
| return (i915.enable_cmd_parser == 1); |
| } |
| |
| static bool check_cmd(const struct intel_engine_cs *ring, |
| const struct drm_i915_cmd_descriptor *desc, |
| const u32 *cmd, u32 length, |
| const bool is_master, |
| bool *oacontrol_set) |
| { |
| if (desc->flags & CMD_DESC_REJECT) { |
| DRM_DEBUG_DRIVER("CMD: Rejected command: 0x%08X\n", *cmd); |
| return false; |
| } |
| |
| if ((desc->flags & CMD_DESC_MASTER) && !is_master) { |
| DRM_DEBUG_DRIVER("CMD: Rejected master-only command: 0x%08X\n", |
| *cmd); |
| return false; |
| } |
| |
| if (desc->flags & CMD_DESC_REGISTER) { |
| /* |
| * Get the distance between individual register offset |
| * fields if the command can perform more than one |
| * access at a time. |
| */ |
| const u32 step = desc->reg.step ? desc->reg.step : length; |
| u32 offset; |
| |
| for (offset = desc->reg.offset; offset < length; |
| offset += step) { |
| const u32 reg_addr = cmd[offset] & desc->reg.mask; |
| const struct drm_i915_reg_descriptor *reg = |
| find_reg(ring->reg_table, ring->reg_count, |
| reg_addr); |
| |
| if (!reg && is_master) |
| reg = find_reg(ring->master_reg_table, |
| ring->master_reg_count, |
| reg_addr); |
| |
| if (!reg) { |
| DRM_DEBUG_DRIVER("CMD: Rejected register 0x%08X in command: 0x%08X (ring=%d)\n", |
| reg_addr, *cmd, ring->id); |
| return false; |
| } |
| |
| /* |
| * OACONTROL requires some special handling for |
| * writes. We want to make sure that any batch which |
| * enables OA also disables it before the end of the |
| * batch. The goal is to prevent one process from |
| * snooping on the perf data from another process. To do |
| * that, we need to check the value that will be written |
| * to the register. Hence, limit OACONTROL writes to |
| * only MI_LOAD_REGISTER_IMM commands. |
| */ |
| if (reg_addr == OACONTROL) { |
| if (desc->cmd.value == MI_LOAD_REGISTER_MEM) { |
| DRM_DEBUG_DRIVER("CMD: Rejected LRM to OACONTROL\n"); |
| return false; |
| } |
| |
| if (desc->cmd.value == MI_LOAD_REGISTER_IMM(1)) |
| *oacontrol_set = (cmd[offset + 1] != 0); |
| } |
| |
| /* |
| * Check the value written to the register against the |
| * allowed mask/value pair given in the whitelist entry. |
| */ |
| if (reg->mask) { |
| if (desc->cmd.value == MI_LOAD_REGISTER_MEM) { |
| DRM_DEBUG_DRIVER("CMD: Rejected LRM to masked register 0x%08X\n", |
| reg_addr); |
| return false; |
| } |
| |
| if (desc->cmd.value == MI_LOAD_REGISTER_IMM(1) && |
| (offset + 2 > length || |
| (cmd[offset + 1] & reg->mask) != reg->value)) { |
| DRM_DEBUG_DRIVER("CMD: Rejected LRI to masked register 0x%08X\n", |
| reg_addr); |
| return false; |
| } |
| } |
| } |
| } |
| |
| if (desc->flags & CMD_DESC_BITMASK) { |
| int i; |
| |
| for (i = 0; i < MAX_CMD_DESC_BITMASKS; i++) { |
| u32 dword; |
| |
| if (desc->bits[i].mask == 0) |
| break; |
| |
| if (desc->bits[i].condition_mask != 0) { |
| u32 offset = |
| desc->bits[i].condition_offset; |
| u32 condition = cmd[offset] & |
| desc->bits[i].condition_mask; |
| |
| if (condition == 0) |
| continue; |
| } |
| |
| dword = cmd[desc->bits[i].offset] & |
| desc->bits[i].mask; |
| |
| if (dword != desc->bits[i].expected) { |
| DRM_DEBUG_DRIVER("CMD: Rejected command 0x%08X for bitmask 0x%08X (exp=0x%08X act=0x%08X) (ring=%d)\n", |
| *cmd, |
| desc->bits[i].mask, |
| desc->bits[i].expected, |
| dword, ring->id); |
| return false; |
| } |
| } |
| } |
| |
| return true; |
| } |
| |
| #define LENGTH_BIAS 2 |
| |
| /** |
| * i915_parse_cmds() - parse a submitted batch buffer for privilege violations |
| * @ring: the ring on which the batch is to execute |
| * @batch_obj: the batch buffer in question |
| * @shadow_batch_obj: copy of the batch buffer in question |
| * @batch_start_offset: byte offset in the batch at which execution starts |
| * @batch_len: length of the commands in batch_obj |
| * @is_master: is the submitting process the drm master? |
| * |
| * Parses the specified batch buffer looking for privilege violations as |
| * described in the overview. |
| * |
| * Return: non-zero if the parser finds violations or otherwise fails; -EACCES |
| * if the batch appears legal but should use hardware parsing |
| */ |
| int i915_parse_cmds(struct intel_engine_cs *ring, |
| struct drm_i915_gem_object *batch_obj, |
| struct drm_i915_gem_object *shadow_batch_obj, |
| u32 batch_start_offset, |
| u32 batch_len, |
| bool is_master) |
| { |
| u32 *cmd, *batch_base, *batch_end; |
| struct drm_i915_cmd_descriptor default_desc = { 0 }; |
| bool oacontrol_set = false; /* OACONTROL tracking. See check_cmd() */ |
| int ret = 0; |
| |
| batch_base = copy_batch(shadow_batch_obj, batch_obj, |
| batch_start_offset, batch_len); |
| if (IS_ERR(batch_base)) { |
| DRM_DEBUG_DRIVER("CMD: Failed to copy batch\n"); |
| return PTR_ERR(batch_base); |
| } |
| |
| /* |
| * We use the batch length as size because the shadow object is as |
| * large or larger and copy_batch() will write MI_NOPs to the extra |
| * space. Parsing should be faster in some cases this way. |
| */ |
| batch_end = batch_base + (batch_len / sizeof(*batch_end)); |
| |
| cmd = batch_base; |
| while (cmd < batch_end) { |
| const struct drm_i915_cmd_descriptor *desc; |
| u32 length; |
| |
| if (*cmd == MI_BATCH_BUFFER_END) |
| break; |
| |
| desc = find_cmd(ring, *cmd, &default_desc); |
| if (!desc) { |
| DRM_DEBUG_DRIVER("CMD: Unrecognized command: 0x%08X\n", |
| *cmd); |
| ret = -EINVAL; |
| break; |
| } |
| |
| /* |
| * If the batch buffer contains a chained batch, return an |
| * error that tells the caller to abort and dispatch the |
| * workload as a non-secure batch. |
| */ |
| if (desc->cmd.value == MI_BATCH_BUFFER_START) { |
| ret = -EACCES; |
| break; |
| } |
| |
| if (desc->flags & CMD_DESC_FIXED) |
| length = desc->length.fixed; |
| else |
| length = ((*cmd & desc->length.mask) + LENGTH_BIAS); |
| |
| if ((batch_end - cmd) < length) { |
| DRM_DEBUG_DRIVER("CMD: Command length exceeds batch length: 0x%08X length=%u batchlen=%td\n", |
| *cmd, |
| length, |
| batch_end - cmd); |
| ret = -EINVAL; |
| break; |
| } |
| |
| if (!check_cmd(ring, desc, cmd, length, is_master, |
| &oacontrol_set)) { |
| ret = -EINVAL; |
| break; |
| } |
| |
| cmd += length; |
| } |
| |
| if (oacontrol_set) { |
| DRM_DEBUG_DRIVER("CMD: batch set OACONTROL but did not clear it\n"); |
| ret = -EINVAL; |
| } |
| |
| if (cmd >= batch_end) { |
| DRM_DEBUG_DRIVER("CMD: Got to the end of the buffer w/o a BBE cmd!\n"); |
| ret = -EINVAL; |
| } |
| |
| vunmap(batch_base); |
| |
| return ret; |
| } |
| |
| /** |
| * i915_cmd_parser_get_version() - get the cmd parser version number |
| * |
| * The cmd parser maintains a simple increasing integer version number suitable |
| * for passing to userspace clients to determine what operations are permitted. |
| * |
| * Return: the current version number of the cmd parser |
| */ |
| int i915_cmd_parser_get_version(void) |
| { |
| /* |
| * Command parser version history |
| * |
| * 1. Initial version. Checks batches and reports violations, but leaves |
| * hardware parsing enabled (so does not allow new use cases). |
| * 2. Allow access to the MI_PREDICATE_SRC0 and |
| * MI_PREDICATE_SRC1 registers. |
| * 3. Allow access to the GPGPU_THREADS_DISPATCHED register. |
| * 4. L3 atomic chicken bits of HSW_SCRATCH1 and HSW_ROW_CHICKEN3. |
| * 5. GPGPU dispatch compute indirect registers. |
| */ |
| return 5; |
| } |