drivers/gpu/drm/vc4/vc4_kms.c

   1 /*
   2  * Copyright (C) 2015 Broadcom
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  */
   8
   9 /**
  10  * DOC: VC4 KMS
  11  *
  12  * This is the general code for implementing KMS mode setting that
  13  * doesn't clearly associate with any of the other objects (plane,
  14  * crtc, HDMI encoder).
  15  */
  16
  17 #include <drm/drm_crtc.h>
  18 #include <drm/drm_atomic.h>
  19 #include <drm/drm_atomic_helper.h>
  20 #include <drm/drm_crtc_helper.h>
  21 #include <drm/drm_plane_helper.h>
  22 #include <drm/drm_gem_framebuffer_helper.h>
  23 #include "vc4_drv.h"
  24 #include "vc4_regs.h"
  25
  26 struct vc4_ctm_state {
  27         struct drm_private_state base;
  28         struct drm_color_ctm *ctm;
  29         int fifo;
  30 };
  31
  32 static struct vc4_ctm_state *to_vc4_ctm_state(struct drm_private_state *priv)
  33 {
  34         return container_of(priv, struct vc4_ctm_state, base);
  35 }
  36
  37 static struct vc4_ctm_state *vc4_get_ctm_state(struct drm_atomic_state *state,
  38                                                struct drm_private_obj *manager)
  39 {
  40         struct drm_device *dev = state->dev;
  41         struct vc4_dev *vc4 = dev->dev_private;
  42         struct drm_private_state *priv_state;
  43         int ret;
  44
  45         ret = drm_modeset_lock(&vc4->ctm_state_lock, state->acquire_ctx);
  46         if (ret)
  47                 return ERR_PTR(ret);
  48
  49         priv_state = drm_atomic_get_private_obj_state(state, manager);
  50         if (IS_ERR(priv_state))
  51                 return ERR_CAST(priv_state);
  52
  53         return to_vc4_ctm_state(priv_state);
  54 }
  55
  56 static struct drm_private_state *
  57 vc4_ctm_duplicate_state(struct drm_private_obj *obj)
  58 {
  59         struct vc4_ctm_state *state;
  60
  61         state = kmemdup(obj->state, sizeof(*state), GFP_KERNEL);
  62         if (!state)
  63                 return NULL;
  64
  65         __drm_atomic_helper_private_obj_duplicate_state(obj, &state->base);
  66
  67         return &state->base;
  68 }
  69
  70 static void vc4_ctm_destroy_state(struct drm_private_obj *obj,
  71                                   struct drm_private_state *state)
  72 {
  73         struct vc4_ctm_state *ctm_state = to_vc4_ctm_state(state);
  74
  75         kfree(ctm_state);
  76 }
  77
  78 static const struct drm_private_state_funcs vc4_ctm_state_funcs = {
  79         .atomic_duplicate_state = vc4_ctm_duplicate_state,
  80         .atomic_destroy_state = vc4_ctm_destroy_state,
  81 };
  82
  83 /* Converts a DRM S31.32 value to the HW S0.9 format. */
  84 static u16 vc4_ctm_s31_32_to_s0_9(u64 in)
  85 {
  86         u16 r;
  87
  88         /* Sign bit. */
  89         r = in & BIT_ULL(63) ? BIT(9) : 0;
  90
  91         if ((in & GENMASK_ULL(62, 32)) > 0) {
  92                 /* We have zero integer bits so we can only saturate here. */
  93                 r |= GENMASK(8, 0);
  94         } else {
  95                 /* Otherwise take the 9 most important fractional bits. */
  96                 r |= (in >> 23) & GENMASK(8, 0);
  97         }
  98
  99         return r;
 100 }
 101
 102 static void
 103 vc4_ctm_commit(struct vc4_dev *vc4, struct drm_atomic_state *state)
 104 {
 105         struct vc4_ctm_state *ctm_state = to_vc4_ctm_state(vc4->ctm_manager.state);
 106         struct drm_color_ctm *ctm = ctm_state->ctm;
 107
 108         if (ctm_state->fifo) {
 109                 HVS_WRITE(SCALER_OLEDCOEF2,
 110                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[0]),
 111                                         SCALER_OLEDCOEF2_R_TO_R) |
 112                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[3]),
 113                                         SCALER_OLEDCOEF2_R_TO_G) |
 114                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[6]),
 115                                         SCALER_OLEDCOEF2_R_TO_B));
 116                 HVS_WRITE(SCALER_OLEDCOEF1,
 117                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[1]),
 118                                         SCALER_OLEDCOEF1_G_TO_R) |
 119                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[4]),
 120                                         SCALER_OLEDCOEF1_G_TO_G) |
 121                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[7]),
 122                                         SCALER_OLEDCOEF1_G_TO_B));
 123                 HVS_WRITE(SCALER_OLEDCOEF0,
 124                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[2]),
 125                                         SCALER_OLEDCOEF0_B_TO_R) |
 126                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[5]),
 127                                         SCALER_OLEDCOEF0_B_TO_G) |
 128                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[8]),
 129                                         SCALER_OLEDCOEF0_B_TO_B));
 130         }
 131
 132         HVS_WRITE(SCALER_OLEDOFFS,
 133                   VC4_SET_FIELD(ctm_state->fifo, SCALER_OLEDOFFS_DISPFIFO));
 134 }
 135
 136 static void
 137 vc4_atomic_complete_commit(struct drm_atomic_state *state)
 138 {
 139         struct drm_device *dev = state->dev;
 140         struct vc4_dev *vc4 = to_vc4_dev(dev);
 141
 142         drm_atomic_helper_wait_for_fences(dev, state, false);
 143
 144         drm_atomic_helper_wait_for_dependencies(state);
 145
 146         drm_atomic_helper_commit_modeset_disables(dev, state);
 147
 148         vc4_ctm_commit(vc4, state);
 149
 150         drm_atomic_helper_commit_planes(dev, state, 0);
 151
 152         drm_atomic_helper_commit_modeset_enables(dev, state);
 153
 154         drm_atomic_helper_fake_vblank(state);
 155
 156         drm_atomic_helper_commit_hw_done(state);
 157
 158         drm_atomic_helper_wait_for_flip_done(dev, state);
 159
 160         drm_atomic_helper_cleanup_planes(dev, state);
 161
 162         drm_atomic_helper_commit_cleanup_done(state);
 163
 164         drm_atomic_state_put(state);
 165
 166         up(&vc4->async_modeset);
 167 }
 168
 169 static void commit_work(struct work_struct *work)
 170 {
 171         struct drm_atomic_state *state = container_of(work,
 172                                                       struct drm_atomic_state,
 173                                                       commit_work);
 174         vc4_atomic_complete_commit(state);
 175 }
 176
 177 /**
 178  * vc4_atomic_commit - commit validated state object
 179  * @dev: DRM device
 180  * @state: the driver state object
 181  * @nonblock: nonblocking commit
 182  *
 183  * This function commits a with drm_atomic_helper_check() pre-validated state
 184  * object. This can still fail when e.g. the framebuffer reservation fails. For
 185  * now this doesn't implement asynchronous commits.
 186  *
 187  * RETURNS
 188  * Zero for success or -errno.
 189  */
 190 static int vc4_atomic_commit(struct drm_device *dev,
 191                              struct drm_atomic_state *state,
 192                              bool nonblock)
 193 {
 194         struct vc4_dev *vc4 = to_vc4_dev(dev);
 195         int ret;
 196
 197         if (state->async_update) {
 198                 ret = down_interruptible(&vc4->async_modeset);
 199                 if (ret)
 200                         return ret;
 201
 202                 ret = drm_atomic_helper_prepare_planes(dev, state);
 203                 if (ret) {
 204                         up(&vc4->async_modeset);
 205                         return ret;
 206                 }
 207
 208                 drm_atomic_helper_async_commit(dev, state);
 209
 210                 drm_atomic_helper_cleanup_planes(dev, state);
 211
 212                 up(&vc4->async_modeset);
 213
 214                 return 0;
 215         }
 216
 217         /* We know for sure we don't want an async update here. Set
 218          * state->legacy_cursor_update to false to prevent
 219          * drm_atomic_helper_setup_commit() from auto-completing
 220          * commit->flip_done.
 221          */
 222         state->legacy_cursor_update = false;
 223         ret = drm_atomic_helper_setup_commit(state, nonblock);
 224         if (ret)
 225                 return ret;
 226
 227         INIT_WORK(&state->commit_work, commit_work);
 228
 229         ret = down_interruptible(&vc4->async_modeset);
 230         if (ret)
 231                 return ret;
 232
 233         ret = drm_atomic_helper_prepare_planes(dev, state);
 234         if (ret) {
 235                 up(&vc4->async_modeset);
 236                 return ret;
 237         }
 238
 239         if (!nonblock) {
 240                 ret = drm_atomic_helper_wait_for_fences(dev, state, true);
 241                 if (ret) {
 242                         drm_atomic_helper_cleanup_planes(dev, state);
 243                         up(&vc4->async_modeset);
 244                         return ret;
 245                 }
 246         }
 247
 248         /*
 249          * This is the point of no return - everything below never fails except
 250          * when the hw goes bonghits. Which means we can commit the new state on
 251          * the software side now.
 252          */
 253
 254         BUG_ON(drm_atomic_helper_swap_state(state, false) < 0);
 255
 256         /*
 257          * Everything below can be run asynchronously without the need to grab
 258          * any modeset locks at all under one condition: It must be guaranteed
 259          * that the asynchronous work has either been cancelled (if the driver
 260          * supports it, which at least requires that the framebuffers get
 261          * cleaned up with drm_atomic_helper_cleanup_planes()) or completed
 262          * before the new state gets committed on the software side with
 263          * drm_atomic_helper_swap_state().
 264          *
 265          * This scheme allows new atomic state updates to be prepared and
 266          * checked in parallel to the asynchronous completion of the previous
 267          * update. Which is important since compositors need to figure out the
 268          * composition of the next frame right after having submitted the
 269          * current layout.
 270          */
 271
 272         drm_atomic_state_get(state);
 273         if (nonblock)
 274                 queue_work(system_unbound_wq, &state->commit_work);
 275         else
 276                 vc4_atomic_complete_commit(state);
 277
 278         return 0;
 279 }
 280
 281 static struct drm_framebuffer *vc4_fb_create(struct drm_device *dev,
 282                                              struct drm_file *file_priv,
 283                                              const struct drm_mode_fb_cmd2 *mode_cmd)
 284 {
 285         struct drm_mode_fb_cmd2 mode_cmd_local;
 286
 287         /* If the user didn't specify a modifier, use the
 288          * vc4_set_tiling_ioctl() state for the BO.
 289          */
 290         if (!(mode_cmd->flags & DRM_MODE_FB_MODIFIERS)) {
 291                 struct drm_gem_object *gem_obj;
 292                 struct vc4_bo *bo;
 293
 294                 gem_obj = drm_gem_object_lookup(file_priv,
 295                                                 mode_cmd->handles[0]);
 296                 if (!gem_obj) {
 297                         DRM_DEBUG("Failed to look up GEM BO %d\n",
 298                                   mode_cmd->handles[0]);
 299                         return ERR_PTR(-ENOENT);
 300                 }
 301                 bo = to_vc4_bo(gem_obj);
 302
 303                 mode_cmd_local = *mode_cmd;
 304
 305                 if (bo->t_format) {
 306                         mode_cmd_local.modifier[0] =
 307                                 DRM_FORMAT_MOD_BROADCOM_VC4_T_TILED;
 308                 } else {
 309                         mode_cmd_local.modifier[0] = DRM_FORMAT_MOD_NONE;
 310                 }
 311
 312                 drm_gem_object_put_unlocked(gem_obj);
 313
 314                 mode_cmd = &mode_cmd_local;
 315         }
 316
 317         return drm_gem_fb_create(dev, file_priv, mode_cmd);
 318 }
 319
 320 /* Our CTM has some peculiar limitations: we can only enable it for one CRTC
 321  * at a time and the HW only supports S0.9 scalars. To account for the latter,
 322  * we don't allow userland to set a CTM that we have no hope of approximating.
 323  */
 324 static int
 325 vc4_ctm_atomic_check(struct drm_device *dev, struct drm_atomic_state *state)
 326 {
 327         struct vc4_dev *vc4 = to_vc4_dev(dev);
 328         struct vc4_ctm_state *ctm_state = NULL;
 329         struct drm_crtc *crtc;
 330         struct drm_crtc_state *old_crtc_state, *new_crtc_state;
 331         struct drm_color_ctm *ctm;
 332         int i;
 333
 334         for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) {
 335                 /* CTM is being disabled. */
 336                 if (!new_crtc_state->ctm && old_crtc_state->ctm) {
 337                         ctm_state = vc4_get_ctm_state(state, &vc4->ctm_manager);
 338                         if (IS_ERR(ctm_state))
 339                                 return PTR_ERR(ctm_state);
 340                         ctm_state->fifo = 0;
 341                 }
 342         }
 343
 344         for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) {
 345                 if (new_crtc_state->ctm == old_crtc_state->ctm)
 346                         continue;
 347
 348                 if (!ctm_state) {
 349                         ctm_state = vc4_get_ctm_state(state, &vc4->ctm_manager);
 350                         if (IS_ERR(ctm_state))
 351                                 return PTR_ERR(ctm_state);
 352                 }
 353
 354                 /* CTM is being enabled or the matrix changed. */
 355                 if (new_crtc_state->ctm) {
 356                         /* fifo is 1-based since 0 disables CTM. */
 357                         int fifo = to_vc4_crtc(crtc)->channel + 1;
 358
 359                         /* Check userland isn't trying to turn on CTM for more
 360                          * than one CRTC at a time.
 361                          */
 362                         if (ctm_state->fifo && ctm_state->fifo != fifo) {
 363                                 DRM_DEBUG_DRIVER("Too many CTM configured\n");
 364                                 return -EINVAL;
 365                         }
 366
 367                         /* Check we can approximate the specified CTM.
 368                          * We disallow scalars |c| > 1.0 since the HW has
 369                          * no integer bits.
 370                          */
 371                         ctm = new_crtc_state->ctm->data;
 372                         for (i = 0; i < ARRAY_SIZE(ctm->matrix); i++) {
 373                                 u64 val = ctm->matrix[i];
 374
 375                                 val &= ~BIT_ULL(63);
 376                                 if (val > BIT_ULL(32))
 377                                         return -EINVAL;
 378                         }
 379
 380                         ctm_state->fifo = fifo;
 381                         ctm_state->ctm = ctm;
 382                 }
 383         }
 384
 385         return 0;
 386 }
 387
 388 static int
 389 vc4_atomic_check(struct drm_device *dev, struct drm_atomic_state *state)
 390 {
 391         int ret;
 392
 393         ret = vc4_ctm_atomic_check(dev, state);
 394         if (ret < 0)
 395                 return ret;
 396
 397         return drm_atomic_helper_check(dev, state);
 398 }
 399
 400 static const struct drm_mode_config_funcs vc4_mode_funcs = {
 401         .atomic_check = vc4_atomic_check,
 402         .atomic_commit = vc4_atomic_commit,
 403         .fb_create = vc4_fb_create,
 404 };
 405
 406 int vc4_kms_load(struct drm_device *dev)
 407 {
 408         struct vc4_dev *vc4 = to_vc4_dev(dev);
 409         struct vc4_ctm_state *ctm_state;
 410         int ret;
 411
 412         sema_init(&vc4->async_modeset, 1);
 413
 414         /* Set support for vblank irq fast disable, before drm_vblank_init() */
 415         dev->vblank_disable_immediate = true;
 416
 417         ret = drm_vblank_init(dev, dev->mode_config.num_crtc);
 418         if (ret < 0) {
 419                 dev_err(dev->dev, "failed to initialize vblank\n");
 420                 return ret;
 421         }
 422
 423         dev->mode_config.max_width = 2048;
 424         dev->mode_config.max_height = 2048;
 425         dev->mode_config.funcs = &vc4_mode_funcs;
 426         dev->mode_config.preferred_depth = 24;
 427         dev->mode_config.async_page_flip = true;
 428         dev->mode_config.allow_fb_modifiers = true;
 429
 430         drm_modeset_lock_init(&vc4->ctm_state_lock);
 431
 432         ctm_state = kzalloc(sizeof(*ctm_state), GFP_KERNEL);
 433         if (!ctm_state)
 434                 return -ENOMEM;
 435         drm_atomic_private_obj_init(&vc4->ctm_manager, &ctm_state->base,
 436                                     &vc4_ctm_state_funcs);
 437
 438         drm_mode_config_reset(dev);
 439
 440         drm_kms_helper_poll_init(dev);
 441
 442         return 0;
 443 }