1 =========================== 1 =========================== 2 drm/i915 Intel GFX Driver 2 drm/i915 Intel GFX Driver 3 =========================== 3 =========================== 4 4 5 The drm/i915 driver supports all (with the exc 5 The drm/i915 driver supports all (with the exception of some very early 6 models) integrated GFX chipsets with both Inte 6 models) integrated GFX chipsets with both Intel display and rendering 7 blocks. This excludes a set of SoC platforms w 7 blocks. This excludes a set of SoC platforms with an SGX rendering unit, 8 those have basic support through the gma500 dr 8 those have basic support through the gma500 drm driver. 9 9 10 Core Driver Infrastructure 10 Core Driver Infrastructure 11 ========================== 11 ========================== 12 12 13 This section covers core driver infrastructure 13 This section covers core driver infrastructure used by both the display 14 and the GEM parts of the driver. 14 and the GEM parts of the driver. 15 15 16 Runtime Power Management 16 Runtime Power Management 17 ------------------------ 17 ------------------------ 18 18 19 .. kernel-doc:: drivers/gpu/drm/i915/intel_run 19 .. kernel-doc:: drivers/gpu/drm/i915/intel_runtime_pm.c 20 :doc: runtime pm 20 :doc: runtime pm 21 21 22 .. kernel-doc:: drivers/gpu/drm/i915/intel_run 22 .. kernel-doc:: drivers/gpu/drm/i915/intel_runtime_pm.c 23 :internal: 23 :internal: 24 24 25 .. kernel-doc:: drivers/gpu/drm/i915/intel_unc 25 .. kernel-doc:: drivers/gpu/drm/i915/intel_uncore.c 26 :internal: 26 :internal: 27 27 28 Interrupt Handling 28 Interrupt Handling 29 ------------------ 29 ------------------ 30 30 31 .. kernel-doc:: drivers/gpu/drm/i915/i915_irq. 31 .. kernel-doc:: drivers/gpu/drm/i915/i915_irq.c 32 :doc: interrupt handling 32 :doc: interrupt handling 33 33 34 .. kernel-doc:: drivers/gpu/drm/i915/i915_irq. 34 .. kernel-doc:: drivers/gpu/drm/i915/i915_irq.c 35 :functions: intel_irq_init intel_irq_init_h 35 :functions: intel_irq_init intel_irq_init_hw intel_hpd_init 36 36 37 .. kernel-doc:: drivers/gpu/drm/i915/i915_irq. 37 .. kernel-doc:: drivers/gpu/drm/i915/i915_irq.c 38 :functions: intel_runtime_pm_disable_interr 38 :functions: intel_runtime_pm_disable_interrupts 39 39 40 .. kernel-doc:: drivers/gpu/drm/i915/i915_irq. 40 .. kernel-doc:: drivers/gpu/drm/i915/i915_irq.c 41 :functions: intel_runtime_pm_enable_interru 41 :functions: intel_runtime_pm_enable_interrupts 42 42 43 Intel GVT-g Guest Support(vGPU) 43 Intel GVT-g Guest Support(vGPU) 44 ------------------------------- 44 ------------------------------- 45 45 46 .. kernel-doc:: drivers/gpu/drm/i915/i915_vgpu 46 .. kernel-doc:: drivers/gpu/drm/i915/i915_vgpu.c 47 :doc: Intel GVT-g guest support 47 :doc: Intel GVT-g guest support 48 48 49 .. kernel-doc:: drivers/gpu/drm/i915/i915_vgpu 49 .. kernel-doc:: drivers/gpu/drm/i915/i915_vgpu.c 50 :internal: 50 :internal: 51 51 52 Intel GVT-g Host Support(vGPU device model) 52 Intel GVT-g Host Support(vGPU device model) 53 ------------------------------------------- 53 ------------------------------------------- 54 54 55 .. kernel-doc:: drivers/gpu/drm/i915/intel_gvt 55 .. kernel-doc:: drivers/gpu/drm/i915/intel_gvt.c 56 :doc: Intel GVT-g host support 56 :doc: Intel GVT-g host support 57 57 58 .. kernel-doc:: drivers/gpu/drm/i915/intel_gvt 58 .. kernel-doc:: drivers/gpu/drm/i915/intel_gvt.c 59 :internal: 59 :internal: 60 60 61 Workarounds 61 Workarounds 62 ----------- 62 ----------- 63 63 64 .. kernel-doc:: drivers/gpu/drm/i915/gt/intel_ !! 64 .. kernel-doc:: drivers/gpu/drm/i915/intel_workarounds.c 65 :doc: Hardware workarounds 65 :doc: Hardware workarounds 66 66 67 Display Hardware Handling 67 Display Hardware Handling 68 ========================= 68 ========================= 69 69 70 This section covers everything related to the 70 This section covers everything related to the display hardware including 71 the mode setting infrastructure, plane, sprite 71 the mode setting infrastructure, plane, sprite and cursor handling and 72 display, output probing and related topics. 72 display, output probing and related topics. 73 73 74 Mode Setting Infrastructure 74 Mode Setting Infrastructure 75 --------------------------- 75 --------------------------- 76 76 77 The i915 driver is thus far the only DRM drive 77 The i915 driver is thus far the only DRM driver which doesn't use the 78 common DRM helper code to implement mode setti 78 common DRM helper code to implement mode setting sequences. Thus it has 79 its own tailor-made infrastructure for executi 79 its own tailor-made infrastructure for executing a display configuration 80 change. 80 change. 81 81 82 Frontbuffer Tracking 82 Frontbuffer Tracking 83 -------------------- 83 -------------------- 84 84 85 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 85 .. kernel-doc:: drivers/gpu/drm/i915/intel_frontbuffer.c 86 :doc: frontbuffer tracking 86 :doc: frontbuffer tracking 87 87 88 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 88 .. kernel-doc:: drivers/gpu/drm/i915/intel_frontbuffer.h 89 :internal: 89 :internal: 90 90 91 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 91 .. kernel-doc:: drivers/gpu/drm/i915/intel_frontbuffer.c 92 :internal: 92 :internal: 93 93 >> 94 .. kernel-doc:: drivers/gpu/drm/i915/i915_gem.c >> 95 :functions: i915_gem_track_fb >> 96 94 Display FIFO Underrun Reporting 97 Display FIFO Underrun Reporting 95 ------------------------------- 98 ------------------------------- 96 99 97 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 100 .. kernel-doc:: drivers/gpu/drm/i915/intel_fifo_underrun.c 98 :doc: fifo underrun handling 101 :doc: fifo underrun handling 99 102 100 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 103 .. kernel-doc:: drivers/gpu/drm/i915/intel_fifo_underrun.c 101 :internal: 104 :internal: 102 105 103 Plane Configuration 106 Plane Configuration 104 ------------------- 107 ------------------- 105 108 106 This section covers plane configuration and co 109 This section covers plane configuration and composition with the primary 107 plane, sprites, cursors and overlays. This inc 110 plane, sprites, cursors and overlays. This includes the infrastructure 108 to do atomic vsync'ed updates of all this stat 111 to do atomic vsync'ed updates of all this state and also tightly coupled 109 topics like watermark setup and computation, f 112 topics like watermark setup and computation, framebuffer compression and 110 panel self refresh. 113 panel self refresh. 111 114 112 Atomic Plane Helpers 115 Atomic Plane Helpers 113 -------------------- 116 -------------------- 114 117 115 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 118 .. kernel-doc:: drivers/gpu/drm/i915/intel_atomic_plane.c 116 :doc: atomic plane helpers 119 :doc: atomic plane helpers 117 120 118 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 121 .. kernel-doc:: drivers/gpu/drm/i915/intel_atomic_plane.c 119 :internal: 122 :internal: 120 123 121 Asynchronous Page Flip << 122 ---------------------- << 123 << 124 .. kernel-doc:: drivers/gpu/drm/i915/display/i << 125 :doc: asynchronous flip implementation << 126 << 127 Output Probing 124 Output Probing 128 -------------- 125 -------------- 129 126 130 This section covers output probing and related 127 This section covers output probing and related infrastructure like the 131 hotplug interrupt storm detection and mitigati 128 hotplug interrupt storm detection and mitigation code. Note that the 132 i915 driver still uses most of the common DRM 129 i915 driver still uses most of the common DRM helper code for output 133 probing, so those sections fully apply. 130 probing, so those sections fully apply. 134 131 135 Hotplug 132 Hotplug 136 ------- 133 ------- 137 134 138 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 135 .. kernel-doc:: drivers/gpu/drm/i915/intel_hotplug.c 139 :doc: Hotplug 136 :doc: Hotplug 140 137 141 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 138 .. kernel-doc:: drivers/gpu/drm/i915/intel_hotplug.c 142 :internal: 139 :internal: 143 140 144 High Definition Audio 141 High Definition Audio 145 --------------------- 142 --------------------- 146 143 147 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 144 .. kernel-doc:: drivers/gpu/drm/i915/intel_audio.c 148 :doc: High Definition Audio over HDMI and D 145 :doc: High Definition Audio over HDMI and Display Port 149 146 150 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 147 .. kernel-doc:: drivers/gpu/drm/i915/intel_audio.c 151 :internal: 148 :internal: 152 149 153 .. kernel-doc:: include/drm/intel/i915_compone !! 150 .. kernel-doc:: include/drm/i915_component.h 154 :internal: 151 :internal: 155 152 156 Intel HDMI LPE Audio Support 153 Intel HDMI LPE Audio Support 157 ---------------------------- 154 ---------------------------- 158 155 159 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 156 .. kernel-doc:: drivers/gpu/drm/i915/intel_lpe_audio.c 160 :doc: LPE Audio integration for HDMI or DP 157 :doc: LPE Audio integration for HDMI or DP playback 161 158 162 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 159 .. kernel-doc:: drivers/gpu/drm/i915/intel_lpe_audio.c 163 :internal: 160 :internal: 164 161 165 Panel Self Refresh PSR (PSR/SRD) 162 Panel Self Refresh PSR (PSR/SRD) 166 -------------------------------- 163 -------------------------------- 167 164 168 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 165 .. kernel-doc:: drivers/gpu/drm/i915/intel_psr.c 169 :doc: Panel Self Refresh (PSR/SRD) 166 :doc: Panel Self Refresh (PSR/SRD) 170 167 171 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 168 .. kernel-doc:: drivers/gpu/drm/i915/intel_psr.c 172 :internal: 169 :internal: 173 170 174 Frame Buffer Compression (FBC) 171 Frame Buffer Compression (FBC) 175 ------------------------------ 172 ------------------------------ 176 173 177 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 174 .. kernel-doc:: drivers/gpu/drm/i915/intel_fbc.c 178 :doc: Frame Buffer Compression (FBC) 175 :doc: Frame Buffer Compression (FBC) 179 176 180 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 177 .. kernel-doc:: drivers/gpu/drm/i915/intel_fbc.c 181 :internal: 178 :internal: 182 179 183 Display Refresh Rate Switching (DRRS) 180 Display Refresh Rate Switching (DRRS) 184 ------------------------------------- 181 ------------------------------------- 185 182 186 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 183 .. kernel-doc:: drivers/gpu/drm/i915/intel_dp.c 187 :doc: Display Refresh Rate Switching (DRRS) 184 :doc: Display Refresh Rate Switching (DRRS) 188 185 189 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 186 .. kernel-doc:: drivers/gpu/drm/i915/intel_dp.c 190 :internal: !! 187 :functions: intel_dp_set_drrs_state >> 188 >> 189 .. kernel-doc:: drivers/gpu/drm/i915/intel_dp.c >> 190 :functions: intel_edp_drrs_enable >> 191 >> 192 .. kernel-doc:: drivers/gpu/drm/i915/intel_dp.c >> 193 :functions: intel_edp_drrs_disable >> 194 >> 195 .. kernel-doc:: drivers/gpu/drm/i915/intel_dp.c >> 196 :functions: intel_edp_drrs_invalidate >> 197 >> 198 .. kernel-doc:: drivers/gpu/drm/i915/intel_dp.c >> 199 :functions: intel_edp_drrs_flush >> 200 >> 201 .. kernel-doc:: drivers/gpu/drm/i915/intel_dp.c >> 202 :functions: intel_dp_drrs_init 191 203 192 DPIO 204 DPIO 193 ---- 205 ---- 194 206 195 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 207 .. kernel-doc:: drivers/gpu/drm/i915/intel_dpio_phy.c 196 :doc: DPIO 208 :doc: DPIO 197 209 198 DMC Firmware Support !! 210 CSR firmware support for DMC 199 -------------------- !! 211 ---------------------------- 200 212 201 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 213 .. kernel-doc:: drivers/gpu/drm/i915/intel_csr.c 202 :doc: DMC Firmware Support !! 214 :doc: csr support for dmc 203 215 204 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 216 .. kernel-doc:: drivers/gpu/drm/i915/intel_csr.c 205 :internal: 217 :internal: 206 218 207 DMC wakelock support << 208 -------------------- << 209 << 210 .. kernel-doc:: drivers/gpu/drm/i915/display/i << 211 :doc: DMC wakelock support << 212 << 213 Video BIOS Table (VBT) 219 Video BIOS Table (VBT) 214 ---------------------- 220 ---------------------- 215 221 216 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 222 .. kernel-doc:: drivers/gpu/drm/i915/intel_bios.c 217 :doc: Video BIOS Table (VBT) 223 :doc: Video BIOS Table (VBT) 218 224 219 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 225 .. kernel-doc:: drivers/gpu/drm/i915/intel_bios.c 220 :internal: 226 :internal: 221 227 222 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 228 .. kernel-doc:: drivers/gpu/drm/i915/intel_vbt_defs.h 223 :internal: 229 :internal: 224 230 225 Display clocks 231 Display clocks 226 -------------- 232 -------------- 227 233 228 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 234 .. kernel-doc:: drivers/gpu/drm/i915/intel_cdclk.c 229 :doc: CDCLK / RAWCLK 235 :doc: CDCLK / RAWCLK 230 236 231 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 237 .. kernel-doc:: drivers/gpu/drm/i915/intel_cdclk.c 232 :internal: 238 :internal: 233 239 234 Display PLLs 240 Display PLLs 235 ------------ 241 ------------ 236 242 237 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 243 .. kernel-doc:: drivers/gpu/drm/i915/intel_dpll_mgr.c 238 :doc: Display PLLs 244 :doc: Display PLLs 239 245 240 .. kernel-doc:: drivers/gpu/drm/i915/display/i !! 246 .. kernel-doc:: drivers/gpu/drm/i915/intel_dpll_mgr.c 241 :internal: << 242 << 243 .. kernel-doc:: drivers/gpu/drm/i915/display/i << 244 :internal: 247 :internal: 245 248 246 Display State Buffer !! 249 .. kernel-doc:: drivers/gpu/drm/i915/intel_dpll_mgr.h 247 -------------------- << 248 << 249 .. kernel-doc:: drivers/gpu/drm/i915/display/i << 250 :doc: DSB << 251 << 252 .. kernel-doc:: drivers/gpu/drm/i915/display/i << 253 :internal: << 254 << 255 GT Programming << 256 ============== << 257 << 258 Multicast/Replicated (MCR) Registers << 259 ------------------------------------ << 260 << 261 .. kernel-doc:: drivers/gpu/drm/i915/gt/intel_ << 262 :doc: GT Multicast/Replicated (MCR) Registe << 263 << 264 .. kernel-doc:: drivers/gpu/drm/i915/gt/intel_ << 265 :internal: 250 :internal: 266 251 267 Memory Management and Command Submission 252 Memory Management and Command Submission 268 ======================================== 253 ======================================== 269 254 270 This sections covers all things related to the 255 This sections covers all things related to the GEM implementation in the 271 i915 driver. 256 i915 driver. 272 257 273 Intel GPU Basics 258 Intel GPU Basics 274 ---------------- 259 ---------------- 275 260 276 An Intel GPU has multiple engines. There are s !! 261 An Intel GPU has multiple engines. There are several engine types. 277 262 278 - Render Command Streamer (RCS). An engine for !! 263 - RCS engine is for rendering 3D and performing compute, this is named 279 performing compute. !! 264 `I915_EXEC_RENDER` in user space. 280 - Blitting Command Streamer (BCS). An engine f !! 265 - BCS is a blitting (copy) engine, this is named `I915_EXEC_BLT` in user 281 copying operations. !! 266 space. 282 - Video Command Streamer. An engine used for v !! 267 - VCS is a video encode and decode engine, this is named `I915_EXEC_BSD` 283 sometimes called 'BSD' in hardware documenta !! 268 in user space 284 - Video Enhancement Command Streamer (VECS). A !! 269 - VECS is video enhancement engine, this is named `I915_EXEC_VEBOX` in user 285 Also sometimes called 'VEBOX' in hardware do !! 270 space. 286 - Compute Command Streamer (CCS). An engine th !! 271 - The enumeration `I915_EXEC_DEFAULT` does not refer to specific engine; 287 GPGPU pipelines, but not the 3D pipeline. !! 272 instead it is to be used by user space to specify a default rendering 288 - Graphics Security Controller (GSCCS). A dedi !! 273 engine (for 3D) that may or may not be the same as RCS. 289 communication with GSC controller on securit << 290 High-bandwidth Digital Content Protection (H << 291 and HuC firmware authentication. << 292 274 293 The Intel GPU family is a family of integrated 275 The Intel GPU family is a family of integrated GPU's using Unified 294 Memory Access. For having the GPU "do work", u 276 Memory Access. For having the GPU "do work", user space will feed the 295 GPU batch buffers via one of the ioctls `DRM_I 277 GPU batch buffers via one of the ioctls `DRM_IOCTL_I915_GEM_EXECBUFFER2` 296 or `DRM_IOCTL_I915_GEM_EXECBUFFER2_WR`. Most s 278 or `DRM_IOCTL_I915_GEM_EXECBUFFER2_WR`. Most such batchbuffers will 297 instruct the GPU to perform work (for example 279 instruct the GPU to perform work (for example rendering) and that work 298 needs memory from which to read and memory to 280 needs memory from which to read and memory to which to write. All memory 299 is encapsulated within GEM buffer objects (usu 281 is encapsulated within GEM buffer objects (usually created with the ioctl 300 `DRM_IOCTL_I915_GEM_CREATE`). An ioctl providi 282 `DRM_IOCTL_I915_GEM_CREATE`). An ioctl providing a batchbuffer for the GPU 301 to create will also list all GEM buffer object 283 to create will also list all GEM buffer objects that the batchbuffer reads 302 and/or writes. For implementation details of m 284 and/or writes. For implementation details of memory management see 303 `GEM BO Management Implementation Details`_. 285 `GEM BO Management Implementation Details`_. 304 286 305 The i915 driver allows user space to create a 287 The i915 driver allows user space to create a context via the ioctl 306 `DRM_IOCTL_I915_GEM_CONTEXT_CREATE` which is i 288 `DRM_IOCTL_I915_GEM_CONTEXT_CREATE` which is identified by a 32-bit 307 integer. Such a context should be viewed by us 289 integer. Such a context should be viewed by user-space as -loosely- 308 analogous to the idea of a CPU process of an o 290 analogous to the idea of a CPU process of an operating system. The i915 309 driver guarantees that commands issued to a fi 291 driver guarantees that commands issued to a fixed context are to be 310 executed so that writes of a previously issued 292 executed so that writes of a previously issued command are seen by 311 reads of following commands. Actions issued be 293 reads of following commands. Actions issued between different contexts 312 (even if from the same file descriptor) are NO 294 (even if from the same file descriptor) are NOT given that guarantee 313 and the only way to synchronize across context 295 and the only way to synchronize across contexts (even from the same 314 file descriptor) is through the use of fences. 296 file descriptor) is through the use of fences. At least as far back as 315 Gen4, also have that a context carries with it 297 Gen4, also have that a context carries with it a GPU HW context; 316 the HW context is essentially (most of at leas !! 298 the HW context is essentially (most of atleast) the state of a GPU. 317 In addition to the ordering guarantees, the ke 299 In addition to the ordering guarantees, the kernel will restore GPU 318 state via HW context when commands are issued 300 state via HW context when commands are issued to a context, this saves 319 user space the need to restore (most of at lea !! 301 user space the need to restore (most of atleast) the GPU state at the 320 start of each batchbuffer. The non-deprecated 302 start of each batchbuffer. The non-deprecated ioctls to submit batchbuffer 321 work can pass that ID (in the lower bits of dr 303 work can pass that ID (in the lower bits of drm_i915_gem_execbuffer2::rsvd1) 322 to identify what context to use with the comma 304 to identify what context to use with the command. 323 305 324 The GPU has its own memory management and addr 306 The GPU has its own memory management and address space. The kernel 325 driver maintains the memory translation table 307 driver maintains the memory translation table for the GPU. For older 326 GPUs (i.e. those before Gen8), there is a sing 308 GPUs (i.e. those before Gen8), there is a single global such translation 327 table, a global Graphics Translation Table (GT 309 table, a global Graphics Translation Table (GTT). For newer generation 328 GPUs each context has its own translation tabl 310 GPUs each context has its own translation table, called Per-Process 329 Graphics Translation Table (PPGTT). Of importa 311 Graphics Translation Table (PPGTT). Of important note, is that although 330 PPGTT is named per-process it is actually per 312 PPGTT is named per-process it is actually per context. When user space 331 submits a batchbuffer, the kernel walks the li 313 submits a batchbuffer, the kernel walks the list of GEM buffer objects 332 used by the batchbuffer and guarantees that no 314 used by the batchbuffer and guarantees that not only is the memory of 333 each such GEM buffer object resident but it is 315 each such GEM buffer object resident but it is also present in the 334 (PP)GTT. If the GEM buffer object is not yet p 316 (PP)GTT. If the GEM buffer object is not yet placed in the (PP)GTT, 335 then it is given an address. Two consequences 317 then it is given an address. Two consequences of this are: the kernel 336 needs to edit the batchbuffer submitted to wri 318 needs to edit the batchbuffer submitted to write the correct value of 337 the GPU address when a GEM BO is assigned a GP 319 the GPU address when a GEM BO is assigned a GPU address and the kernel 338 might evict a different GEM BO from the (PP)GT 320 might evict a different GEM BO from the (PP)GTT to make address room 339 for another GEM BO. Consequently, the ioctls s 321 for another GEM BO. Consequently, the ioctls submitting a batchbuffer 340 for execution also include a list of all locat 322 for execution also include a list of all locations within buffers that 341 refer to GPU-addresses so that the kernel can 323 refer to GPU-addresses so that the kernel can edit the buffer correctly. 342 This process is dubbed relocation. 324 This process is dubbed relocation. 343 325 344 Locking Guidelines << 345 ------------------ << 346 << 347 .. note:: << 348 This is a description of how the locking sh << 349 refactoring is done. Does not necessarily r << 350 looks like while WIP. << 351 << 352 #. All locking rules and interface contracts w << 353 (dma-buf, dma_fence) need to be followed. << 354 << 355 #. No struct_mutex anywhere in the code << 356 << 357 #. dma_resv will be the outermost lock (when n << 358 is to be hoisted at highest level and passe << 359 in the call chain << 360 << 361 #. While holding lru/memory manager (buddy, dr << 362 system memory allocations are not allowed << 363 << 364 * Enforce this by priming lockdep (wit << 365 allocate memory while holding these << 366 of the shrinker vs. struct_mutex sag << 367 real bad. << 368 << 369 #. Do not nest different lru/memory manager lo << 370 Take them in turn to update memory allocati << 371 dma_resv ww_mutex to serialize against othe << 372 << 373 #. The suggestion for lru/memory managers lock << 374 enough to be spinlocks. << 375 << 376 #. All features need to come with exhaustive k << 377 IGT tests when appropriate << 378 << 379 #. All LMEM uAPI paths need to be fully restar << 380 for all locks/waits/sleeps) << 381 << 382 * Error handling validation through si << 383 Still the best strategy we have for << 384 corner cases. << 385 Must be excessively used in the IGT, << 386 that we really have full path covera << 387 << 388 * -EDEADLK handling with ww_mutex << 389 << 390 GEM BO Management Implementation Details 326 GEM BO Management Implementation Details 391 ---------------------------------------- 327 ---------------------------------------- 392 328 393 .. kernel-doc:: drivers/gpu/drm/i915/i915_vma_ !! 329 .. kernel-doc:: drivers/gpu/drm/i915/i915_vma.h 394 :doc: Virtual Memory Address 330 :doc: Virtual Memory Address 395 331 396 Buffer Object Eviction 332 Buffer Object Eviction 397 ---------------------- 333 ---------------------- 398 334 399 This section documents the interface functions 335 This section documents the interface functions for evicting buffer 400 objects to make space available in the virtual 336 objects to make space available in the virtual gpu address spaces. Note 401 that this is mostly orthogonal to shrinking bu 337 that this is mostly orthogonal to shrinking buffer objects caches, which 402 has the goal to make main memory (shared with 338 has the goal to make main memory (shared with the gpu through the 403 unified memory architecture) available. 339 unified memory architecture) available. 404 340 405 .. kernel-doc:: drivers/gpu/drm/i915/i915_gem_ 341 .. kernel-doc:: drivers/gpu/drm/i915/i915_gem_evict.c 406 :internal: 342 :internal: 407 343 408 Buffer Object Memory Shrinking 344 Buffer Object Memory Shrinking 409 ------------------------------ 345 ------------------------------ 410 346 411 This section documents the interface function 347 This section documents the interface function for shrinking memory usage 412 of buffer object caches. Shrinking is used to 348 of buffer object caches. Shrinking is used to make main memory 413 available. Note that this is mostly orthogonal 349 available. Note that this is mostly orthogonal to evicting buffer 414 objects, which has the goal to make space in g 350 objects, which has the goal to make space in gpu virtual address spaces. 415 351 416 .. kernel-doc:: drivers/gpu/drm/i915/gem/i915_ !! 352 .. kernel-doc:: drivers/gpu/drm/i915/i915_gem_shrinker.c 417 :internal: 353 :internal: 418 354 419 Batchbuffer Parsing 355 Batchbuffer Parsing 420 ------------------- 356 ------------------- 421 357 422 .. kernel-doc:: drivers/gpu/drm/i915/i915_cmd_ 358 .. kernel-doc:: drivers/gpu/drm/i915/i915_cmd_parser.c 423 :doc: batch buffer command parser 359 :doc: batch buffer command parser 424 360 425 .. kernel-doc:: drivers/gpu/drm/i915/i915_cmd_ 361 .. kernel-doc:: drivers/gpu/drm/i915/i915_cmd_parser.c 426 :internal: 362 :internal: 427 363 >> 364 Batchbuffer Pools >> 365 ----------------- >> 366 >> 367 .. kernel-doc:: drivers/gpu/drm/i915/i915_gem_batch_pool.c >> 368 :doc: batch pool >> 369 >> 370 .. kernel-doc:: drivers/gpu/drm/i915/i915_gem_batch_pool.c >> 371 :internal: >> 372 428 User Batchbuffer Execution 373 User Batchbuffer Execution 429 -------------------------- 374 -------------------------- 430 375 431 .. kernel-doc:: drivers/gpu/drm/i915/gem/i915_ !! 376 .. kernel-doc:: drivers/gpu/drm/i915/i915_gem_execbuffer.c 432 << 433 .. kernel-doc:: drivers/gpu/drm/i915/gem/i915_ << 434 :doc: User command execution 377 :doc: User command execution 435 378 436 Scheduling << 437 ---------- << 438 .. kernel-doc:: drivers/gpu/drm/i915/i915_sche << 439 :functions: i915_sched_engine << 440 << 441 Logical Rings, Logical Ring Contexts and Execl 379 Logical Rings, Logical Ring Contexts and Execlists 442 ---------------------------------------------- 380 -------------------------------------------------- 443 381 444 .. kernel-doc:: drivers/gpu/drm/i915/gt/intel_ !! 382 .. kernel-doc:: drivers/gpu/drm/i915/intel_lrc.c 445 :doc: Logical Rings, Logical Ring Contexts 383 :doc: Logical Rings, Logical Ring Contexts and Execlists 446 384 >> 385 .. kernel-doc:: drivers/gpu/drm/i915/intel_lrc.c >> 386 :internal: >> 387 447 Global GTT views 388 Global GTT views 448 ---------------- 389 ---------------- 449 390 450 .. kernel-doc:: drivers/gpu/drm/i915/i915_vma_ !! 391 .. kernel-doc:: drivers/gpu/drm/i915/i915_gem_gtt.c 451 :doc: Global GTT views 392 :doc: Global GTT views 452 393 453 .. kernel-doc:: drivers/gpu/drm/i915/i915_gem_ 394 .. kernel-doc:: drivers/gpu/drm/i915/i915_gem_gtt.c 454 :internal: 395 :internal: 455 396 456 GTT Fences and Swizzling 397 GTT Fences and Swizzling 457 ------------------------ 398 ------------------------ 458 399 459 .. kernel-doc:: drivers/gpu/drm/i915/gt/intel_ !! 400 .. kernel-doc:: drivers/gpu/drm/i915/i915_gem_fence_reg.c 460 :internal: 401 :internal: 461 402 462 Global GTT Fence Handling 403 Global GTT Fence Handling 463 ~~~~~~~~~~~~~~~~~~~~~~~~~ 404 ~~~~~~~~~~~~~~~~~~~~~~~~~ 464 405 465 .. kernel-doc:: drivers/gpu/drm/i915/gt/intel_ !! 406 .. kernel-doc:: drivers/gpu/drm/i915/i915_gem_fence_reg.c 466 :doc: fence register handling 407 :doc: fence register handling 467 408 468 Hardware Tiling and Swizzling Details 409 Hardware Tiling and Swizzling Details 469 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 410 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 470 411 471 .. kernel-doc:: drivers/gpu/drm/i915/gt/intel_ !! 412 .. kernel-doc:: drivers/gpu/drm/i915/i915_gem_fence_reg.c 472 :doc: tiling swizzling details 413 :doc: tiling swizzling details 473 414 474 Object Tiling IOCTLs 415 Object Tiling IOCTLs 475 -------------------- 416 -------------------- 476 417 477 .. kernel-doc:: drivers/gpu/drm/i915/gem/i915_ !! 418 .. kernel-doc:: drivers/gpu/drm/i915/i915_gem_tiling.c 478 :internal: 419 :internal: 479 420 480 .. kernel-doc:: drivers/gpu/drm/i915/gem/i915_ !! 421 .. kernel-doc:: drivers/gpu/drm/i915/i915_gem_tiling.c 481 :doc: buffer object tiling 422 :doc: buffer object tiling 482 423 483 Protected Objects << 484 ----------------- << 485 << 486 .. kernel-doc:: drivers/gpu/drm/i915/pxp/intel << 487 :doc: PXP << 488 << 489 .. kernel-doc:: drivers/gpu/drm/i915/pxp/intel << 490 << 491 Microcontrollers << 492 ================ << 493 << 494 Starting from gen9, three microcontrollers are << 495 graphics microcontroller (GuC), the HEVC/H.265 << 496 display microcontroller (DMC). The driver is r << 497 firmwares on the microcontrollers; the GuC and << 498 to WOPCM using the DMA engine, while the DMC f << 499 << 500 WOPCM 424 WOPCM 501 ----- !! 425 ===== 502 426 503 WOPCM Layout 427 WOPCM Layout 504 ~~~~~~~~~~~~ !! 428 ------------ 505 429 506 .. kernel-doc:: drivers/gpu/drm/i915/gt/intel_ !! 430 .. kernel-doc:: drivers/gpu/drm/i915/intel_wopcm.c 507 :doc: WOPCM Layout 431 :doc: WOPCM Layout 508 432 509 GuC 433 GuC 510 --- !! 434 === 511 << 512 .. kernel-doc:: drivers/gpu/drm/i915/gt/uc/int << 513 :doc: GuC << 514 << 515 .. kernel-doc:: drivers/gpu/drm/i915/gt/uc/int << 516 << 517 GuC Firmware Layout << 518 ~~~~~~~~~~~~~~~~~~~ << 519 << 520 .. kernel-doc:: drivers/gpu/drm/i915/gt/uc/int << 521 :doc: Firmware Layout << 522 << 523 GuC Memory Management << 524 ~~~~~~~~~~~~~~~~~~~~~ << 525 << 526 .. kernel-doc:: drivers/gpu/drm/i915/gt/uc/int << 527 :doc: GuC Memory Management << 528 .. kernel-doc:: drivers/gpu/drm/i915/gt/uc/int << 529 :functions: intel_guc_allocate_vma << 530 << 531 435 532 GuC-specific firmware loader 436 GuC-specific firmware loader 533 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ !! 437 ---------------------------- 534 438 535 .. kernel-doc:: drivers/gpu/drm/i915/gt/uc/int !! 439 .. kernel-doc:: drivers/gpu/drm/i915/intel_guc_fw.c 536 :internal: 440 :internal: 537 441 538 GuC-based command submission 442 GuC-based command submission 539 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ !! 443 ---------------------------- 540 444 541 .. kernel-doc:: drivers/gpu/drm/i915/gt/uc/int !! 445 .. kernel-doc:: drivers/gpu/drm/i915/intel_guc_submission.c 542 :doc: GuC-based command submission 446 :doc: GuC-based command submission 543 447 544 GuC ABI !! 448 .. kernel-doc:: drivers/gpu/drm/i915/intel_guc_submission.c 545 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ !! 449 :internal: >> 450 >> 451 GuC Firmware Layout >> 452 ------------------- >> 453 >> 454 .. kernel-doc:: drivers/gpu/drm/i915/intel_guc_fwif.h >> 455 :doc: GuC Firmware Layout >> 456 >> 457 GuC Address Space >> 458 ----------------- 546 459 547 .. kernel-doc:: drivers/gpu/drm/i915/gt/uc/abi !! 460 .. kernel-doc:: drivers/gpu/drm/i915/intel_guc.c 548 .. kernel-doc:: drivers/gpu/drm/i915/gt/uc/abi !! 461 :doc: GuC Address Space 549 .. kernel-doc:: drivers/gpu/drm/i915/gt/uc/abi << 550 .. kernel-doc:: drivers/gpu/drm/i915/gt/uc/abi << 551 .. kernel-doc:: drivers/gpu/drm/i915/gt/uc/abi << 552 << 553 HuC << 554 --- << 555 .. kernel-doc:: drivers/gpu/drm/i915/gt/uc/int << 556 :doc: HuC << 557 .. kernel-doc:: drivers/gpu/drm/i915/gt/uc/int << 558 :functions: intel_huc_auth << 559 << 560 HuC Memory Management << 561 ~~~~~~~~~~~~~~~~~~~~~ << 562 << 563 .. kernel-doc:: drivers/gpu/drm/i915/gt/uc/int << 564 :doc: HuC Memory Management << 565 << 566 HuC Firmware Layout << 567 ~~~~~~~~~~~~~~~~~~~ << 568 The HuC FW layout is the same as the GuC one, << 569 << 570 DMC << 571 --- << 572 See `DMC Firmware Support`_ << 573 462 574 Tracing 463 Tracing 575 ======= 464 ======= 576 465 577 This sections covers all things related to the 466 This sections covers all things related to the tracepoints implemented 578 in the i915 driver. 467 in the i915 driver. 579 468 580 i915_ppgtt_create and i915_ppgtt_release 469 i915_ppgtt_create and i915_ppgtt_release 581 ---------------------------------------- 470 ---------------------------------------- 582 471 583 .. kernel-doc:: drivers/gpu/drm/i915/i915_trac 472 .. kernel-doc:: drivers/gpu/drm/i915/i915_trace.h 584 :doc: i915_ppgtt_create and i915_ppgtt_rele 473 :doc: i915_ppgtt_create and i915_ppgtt_release tracepoints 585 474 586 i915_context_create and i915_context_free 475 i915_context_create and i915_context_free 587 ----------------------------------------- 476 ----------------------------------------- 588 477 589 .. kernel-doc:: drivers/gpu/drm/i915/i915_trac 478 .. kernel-doc:: drivers/gpu/drm/i915/i915_trace.h 590 :doc: i915_context_create and i915_context_ 479 :doc: i915_context_create and i915_context_free tracepoints 591 480 >> 481 switch_mm >> 482 --------- >> 483 >> 484 .. kernel-doc:: drivers/gpu/drm/i915/i915_trace.h >> 485 :doc: switch_mm tracepoint >> 486 592 Perf 487 Perf 593 ==== 488 ==== 594 489 595 Overview 490 Overview 596 -------- 491 -------- 597 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 492 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 598 :doc: i915 Perf Overview 493 :doc: i915 Perf Overview 599 494 600 Comparison with Core Perf 495 Comparison with Core Perf 601 ------------------------- 496 ------------------------- 602 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 497 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 603 :doc: i915 Perf History and Comparison with 498 :doc: i915 Perf History and Comparison with Core Perf 604 499 605 i915 Driver Entry Points 500 i915 Driver Entry Points 606 ------------------------ 501 ------------------------ 607 502 608 This section covers the entrypoints exported o 503 This section covers the entrypoints exported outside of i915_perf.c to 609 integrate with drm/i915 and to handle the `DRM 504 integrate with drm/i915 and to handle the `DRM_I915_PERF_OPEN` ioctl. 610 505 611 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 506 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 612 :functions: i915_perf_init 507 :functions: i915_perf_init 613 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 508 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 614 :functions: i915_perf_fini 509 :functions: i915_perf_fini 615 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 510 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 616 :functions: i915_perf_register 511 :functions: i915_perf_register 617 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 512 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 618 :functions: i915_perf_unregister 513 :functions: i915_perf_unregister 619 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 514 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 620 :functions: i915_perf_open_ioctl 515 :functions: i915_perf_open_ioctl 621 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 516 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 622 :functions: i915_perf_release 517 :functions: i915_perf_release 623 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 518 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 624 :functions: i915_perf_add_config_ioctl 519 :functions: i915_perf_add_config_ioctl 625 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 520 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 626 :functions: i915_perf_remove_config_ioctl 521 :functions: i915_perf_remove_config_ioctl 627 522 628 i915 Perf Stream 523 i915 Perf Stream 629 ---------------- 524 ---------------- 630 525 631 This section covers the stream-semantics-agnos 526 This section covers the stream-semantics-agnostic structures and functions 632 for representing an i915 perf stream FD and as 527 for representing an i915 perf stream FD and associated file operations. 633 528 634 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf !! 529 .. kernel-doc:: drivers/gpu/drm/i915/i915_drv.h 635 :functions: i915_perf_stream 530 :functions: i915_perf_stream 636 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf !! 531 .. kernel-doc:: drivers/gpu/drm/i915/i915_drv.h 637 :functions: i915_perf_stream_ops 532 :functions: i915_perf_stream_ops 638 533 639 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 534 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 640 :functions: read_properties_unlocked 535 :functions: read_properties_unlocked 641 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 536 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 642 :functions: i915_perf_open_ioctl_locked 537 :functions: i915_perf_open_ioctl_locked 643 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 538 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 644 :functions: i915_perf_destroy_locked 539 :functions: i915_perf_destroy_locked 645 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 540 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 646 :functions: i915_perf_read 541 :functions: i915_perf_read 647 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 542 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 648 :functions: i915_perf_ioctl 543 :functions: i915_perf_ioctl 649 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 544 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 650 :functions: i915_perf_enable_locked 545 :functions: i915_perf_enable_locked 651 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 546 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 652 :functions: i915_perf_disable_locked 547 :functions: i915_perf_disable_locked 653 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 548 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 654 :functions: i915_perf_poll 549 :functions: i915_perf_poll 655 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 550 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 656 :functions: i915_perf_poll_locked 551 :functions: i915_perf_poll_locked 657 552 658 i915 Perf Observation Architecture Stream 553 i915 Perf Observation Architecture Stream 659 ----------------------------------------- 554 ----------------------------------------- 660 555 661 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf !! 556 .. kernel-doc:: drivers/gpu/drm/i915/i915_drv.h 662 :functions: i915_oa_ops 557 :functions: i915_oa_ops 663 558 664 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 559 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 665 :functions: i915_oa_stream_init 560 :functions: i915_oa_stream_init 666 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 561 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 667 :functions: i915_oa_read 562 :functions: i915_oa_read 668 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 563 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 669 :functions: i915_oa_stream_enable 564 :functions: i915_oa_stream_enable 670 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 565 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 671 :functions: i915_oa_stream_disable 566 :functions: i915_oa_stream_disable 672 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 567 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 673 :functions: i915_oa_wait_unlocked 568 :functions: i915_oa_wait_unlocked 674 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 569 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 675 :functions: i915_oa_poll_wait 570 :functions: i915_oa_poll_wait 676 571 677 Other i915 Perf Internals !! 572 All i915 Perf Internals 678 ------------------------- !! 573 ----------------------- 679 574 680 This section simply includes all other current !! 575 This section simply includes all currently documented i915 perf internals, in 681 in no particular order, but may include some m !! 576 no particular order, but may include some more minor utilities or platform 682 specific details than found in the more high-l 577 specific details than found in the more high-level sections. 683 578 684 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf 579 .. kernel-doc:: drivers/gpu/drm/i915/i915_perf.c 685 :internal: 580 :internal: 686 :no-identifiers: << 687 i915_perf_init << 688 i915_perf_fini << 689 i915_perf_register << 690 i915_perf_unregister << 691 i915_perf_open_ioctl << 692 i915_perf_release << 693 i915_perf_add_config_ioctl << 694 i915_perf_remove_config_ioctl << 695 read_properties_unlocked << 696 i915_perf_open_ioctl_locked << 697 i915_perf_destroy_locked << 698 i915_perf_read i915_perf_ioctl << 699 i915_perf_enable_locked << 700 i915_perf_disable_locked << 701 i915_perf_poll i915_perf_poll_locked << 702 i915_oa_stream_init i915_oa_read << 703 i915_oa_stream_enable << 704 i915_oa_stream_disable << 705 i915_oa_wait_unlocked << 706 i915_oa_poll_wait << 707 581 708 Style 582 Style 709 ===== 583 ===== 710 584 711 The drm/i915 driver codebase has some style ru 585 The drm/i915 driver codebase has some style rules in addition to (and, in some 712 cases, deviating from) the kernel coding style 586 cases, deviating from) the kernel coding style. 713 587 714 Register macro definition style 588 Register macro definition style 715 ------------------------------- 589 ------------------------------- 716 590 717 The style guide for ``i915_reg.h``. 591 The style guide for ``i915_reg.h``. 718 592 719 .. kernel-doc:: drivers/gpu/drm/i915/i915_reg. 593 .. kernel-doc:: drivers/gpu/drm/i915/i915_reg.h 720 :doc: The i915 register macro definition st 594 :doc: The i915 register macro definition style guide 721 << 722 .. _i915-usage-stats: << 723 << 724 i915 DRM client usage stats implementation << 725 ========================================== << 726 << 727 The drm/i915 driver implements the DRM client << 728 documented in :ref:`drm-client-usage-stats`. << 729 << 730 Example of the output showing the implemented << 731 the currently possible format options: << 732 << 733 :: << 734 << 735 pos: 0 << 736 flags: 0100002 << 737 mnt_id: 21 << 738 drm-driver: i915 << 739 drm-pdev: 0000:00:02.0 << 740 drm-client-id: 7 << 741 drm-engine-render: 9288864723 ns << 742 drm-engine-copy: 2035071108 ns << 743 drm-engine-video: 0 ns << 744 drm-engine-capacity-video: 2 << 745 drm-engine-video-enhance: 0 ns << 746 << 747 Possible `drm-engine-` key names are: `render` << 748 `video-enhance`. <<
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