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         ret = drm_atomic_helper_setup_commit(state, nonblock);
 218         if (ret)
 219                 return ret;
 220
 221         INIT_WORK(&state->commit_work, commit_work);
 222
 223         ret = down_interruptible(&vc4->async_modeset);
 224         if (ret)
 225                 return ret;
 226
 227         ret = drm_atomic_helper_prepare_planes(dev, state);
 228         if (ret) {
 229                 up(&vc4->async_modeset);
 230                 return ret;
 231         }
 232
 233         if (!nonblock) {
 234                 ret = drm_atomic_helper_wait_for_fences(dev, state, true);
 235                 if (ret) {
 236                         drm_atomic_helper_cleanup_planes(dev, state);
 237                         up(&vc4->async_modeset);
 238                         return ret;
 239                 }
 240         }
 241
 242         /*
 243          * This is the point of no return - everything below never fails except
 244          * when the hw goes bonghits. Which means we can commit the new state on
 245          * the software side now.
 246          */
 247
 248         BUG_ON(drm_atomic_helper_swap_state(state, false) < 0);
 249
 250         /*
 251          * Everything below can be run asynchronously without the need to grab
 252          * any modeset locks at all under one condition: It must be guaranteed
 253          * that the asynchronous work has either been cancelled (if the driver
 254          * supports it, which at least requires that the framebuffers get
 255          * cleaned up with drm_atomic_helper_cleanup_planes()) or completed
 256          * before the new state gets committed on the software side with
 257          * drm_atomic_helper_swap_state().
 258          *
 259          * This scheme allows new atomic state updates to be prepared and
 260          * checked in parallel to the asynchronous completion of the previous
 261          * update. Which is important since compositors need to figure out the
 262          * composition of the next frame right after having submitted the
 263          * current layout.
 264          */
 265
 266         drm_atomic_state_get(state);
 267         if (nonblock)
 268                 queue_work(system_unbound_wq, &state->commit_work);
 269         else
 270                 vc4_atomic_complete_commit(state);
 271
 272         return 0;
 273 }
 274
 275 static struct drm_framebuffer *vc4_fb_create(struct drm_device *dev,
 276                                              struct drm_file *file_priv,
 277                                              const struct drm_mode_fb_cmd2 *mode_cmd)
 278 {
 279         struct drm_mode_fb_cmd2 mode_cmd_local;
 280
 281         /* If the user didn't specify a modifier, use the
 282          * vc4_set_tiling_ioctl() state for the BO.
 283          */
 284         if (!(mode_cmd->flags & DRM_MODE_FB_MODIFIERS)) {
 285                 struct drm_gem_object *gem_obj;
 286                 struct vc4_bo *bo;
 287
 288                 gem_obj = drm_gem_object_lookup(file_priv,
 289                                                 mode_cmd->handles[0]);
 290                 if (!gem_obj) {
 291                         DRM_DEBUG("Failed to look up GEM BO %d\n",
 292                                   mode_cmd->handles[0]);
 293                         return ERR_PTR(-ENOENT);
 294                 }
 295                 bo = to_vc4_bo(gem_obj);
 296
 297                 mode_cmd_local = *mode_cmd;
 298
 299                 if (bo->t_format) {
 300                         mode_cmd_local.modifier[0] =
 301                                 DRM_FORMAT_MOD_BROADCOM_VC4_T_TILED;
 302                 } else {
 303                         mode_cmd_local.modifier[0] = DRM_FORMAT_MOD_NONE;
 304                 }
 305
 306                 drm_gem_object_put_unlocked(gem_obj);
 307
 308                 mode_cmd = &mode_cmd_local;
 309         }
 310
 311         return drm_gem_fb_create(dev, file_priv, mode_cmd);
 312 }
 313
 314 /* Our CTM has some peculiar limitations: we can only enable it for one CRTC
 315  * at a time and the HW only supports S0.9 scalars. To account for the latter,
 316  * we don't allow userland to set a CTM that we have no hope of approximating.
 317  */
 318 static int
 319 vc4_ctm_atomic_check(struct drm_device *dev, struct drm_atomic_state *state)
 320 {
 321         struct vc4_dev *vc4 = to_vc4_dev(dev);
 322         struct vc4_ctm_state *ctm_state = NULL;
 323         struct drm_crtc *crtc;
 324         struct drm_crtc_state *old_crtc_state, *new_crtc_state;
 325         struct drm_color_ctm *ctm;
 326         int i;
 327
 328         for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) {
 329                 /* CTM is being disabled. */
 330                 if (!new_crtc_state->ctm && old_crtc_state->ctm) {
 331                         ctm_state = vc4_get_ctm_state(state, &vc4->ctm_manager);
 332                         if (IS_ERR(ctm_state))
 333                                 return PTR_ERR(ctm_state);
 334                         ctm_state->fifo = 0;
 335                 }
 336         }
 337
 338         for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) {
 339                 if (new_crtc_state->ctm == old_crtc_state->ctm)
 340                         continue;
 341
 342                 if (!ctm_state) {
 343                         ctm_state = vc4_get_ctm_state(state, &vc4->ctm_manager);
 344                         if (IS_ERR(ctm_state))
 345                                 return PTR_ERR(ctm_state);
 346                 }
 347
 348                 /* CTM is being enabled or the matrix changed. */
 349                 if (new_crtc_state->ctm) {
 350                         /* fifo is 1-based since 0 disables CTM. */
 351                         int fifo = to_vc4_crtc(crtc)->channel + 1;
 352
 353                         /* Check userland isn't trying to turn on CTM for more
 354                          * than one CRTC at a time.
 355                          */
 356                         if (ctm_state->fifo && ctm_state->fifo != fifo) {
 357                                 DRM_DEBUG_DRIVER("Too many CTM configured\n");
 358                                 return -EINVAL;
 359                         }
 360
 361                         /* Check we can approximate the specified CTM.
 362                          * We disallow scalars |c| > 1.0 since the HW has
 363                          * no integer bits.
 364                          */
 365                         ctm = new_crtc_state->ctm->data;
 366                         for (i = 0; i < ARRAY_SIZE(ctm->matrix); i++) {
 367                                 u64 val = ctm->matrix[i];
 368
 369                                 val &= ~BIT_ULL(63);
 370                                 if (val > BIT_ULL(32))
 371                                         return -EINVAL;
 372                         }
 373
 374                         ctm_state->fifo = fifo;
 375                         ctm_state->ctm = ctm;
 376                 }
 377         }
 378
 379         return 0;
 380 }
 381
 382 static int
 383 vc4_atomic_check(struct drm_device *dev, struct drm_atomic_state *state)
 384 {
 385         int ret;
 386
 387         ret = vc4_ctm_atomic_check(dev, state);
 388         if (ret < 0)
 389                 return ret;
 390
 391         return drm_atomic_helper_check(dev, state);
 392 }
 393
 394 static const struct drm_mode_config_funcs vc4_mode_funcs = {
 395         .atomic_check = vc4_atomic_check,
 396         .atomic_commit = vc4_atomic_commit,
 397         .fb_create = vc4_fb_create,
 398 };
 399
 400 int vc4_kms_load(struct drm_device *dev)
 401 {
 402         struct vc4_dev *vc4 = to_vc4_dev(dev);
 403         struct vc4_ctm_state *ctm_state;
 404         int ret;
 405
 406         sema_init(&vc4->async_modeset, 1);
 407
 408         /* Set support for vblank irq fast disable, before drm_vblank_init() */
 409         dev->vblank_disable_immediate = true;
 410
 411         ret = drm_vblank_init(dev, dev->mode_config.num_crtc);
 412         if (ret < 0) {
 413                 dev_err(dev->dev, "failed to initialize vblank\n");
 414                 return ret;
 415         }
 416
 417         dev->mode_config.max_width = 2048;
 418         dev->mode_config.max_height = 2048;
 419         dev->mode_config.funcs = &vc4_mode_funcs;
 420         dev->mode_config.preferred_depth = 24;
 421         dev->mode_config.async_page_flip = true;
 422         dev->mode_config.allow_fb_modifiers = true;
 423
 424         drm_modeset_lock_init(&vc4->ctm_state_lock);
 425
 426         ctm_state = kzalloc(sizeof(*ctm_state), GFP_KERNEL);
 427         if (!ctm_state)
 428                 return -ENOMEM;
 429         drm_atomic_private_obj_init(&vc4->ctm_manager, &ctm_state->base,
 430                                     &vc4_ctm_state_funcs);
 431
 432         drm_mode_config_reset(dev);
 433
 434         drm_kms_helper_poll_init(dev);
 435
 436         return 0;
 437 }