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_fb_helper.h>
  23 #include <drm/drm_fb_cma_helper.h>
  24 #include <drm/drm_gem_framebuffer_helper.h>
  25 #include "vc4_drv.h"
  26 #include "vc4_regs.h"
  27
  28 struct vc4_ctm_state {
  29         struct drm_private_state base;
  30         struct drm_color_ctm *ctm;
  31         int fifo;
  32 };
  33
  34 static struct vc4_ctm_state *to_vc4_ctm_state(struct drm_private_state *priv)
  35 {
  36         return container_of(priv, struct vc4_ctm_state, base);
  37 }
  38
  39 static struct vc4_ctm_state *vc4_get_ctm_state(struct drm_atomic_state *state,
  40                                                struct drm_private_obj *manager)
  41 {
  42         struct drm_device *dev = state->dev;
  43         struct vc4_dev *vc4 = dev->dev_private;
  44         struct drm_private_state *priv_state;
  45         int ret;
  46
  47         ret = drm_modeset_lock(&vc4->ctm_state_lock, state->acquire_ctx);
  48         if (ret)
  49                 return ERR_PTR(ret);
  50
  51         priv_state = drm_atomic_get_private_obj_state(state, manager);
  52         if (IS_ERR(priv_state))
  53                 return ERR_CAST(priv_state);
  54
  55         return to_vc4_ctm_state(priv_state);
  56 }
  57
  58 static struct drm_private_state *
  59 vc4_ctm_duplicate_state(struct drm_private_obj *obj)
  60 {
  61         struct vc4_ctm_state *state;
  62
  63         state = kmemdup(obj->state, sizeof(*state), GFP_KERNEL);
  64         if (!state)
  65                 return NULL;
  66
  67         __drm_atomic_helper_private_obj_duplicate_state(obj, &state->base);
  68
  69         return &state->base;
  70 }
  71
  72 static void vc4_ctm_destroy_state(struct drm_private_obj *obj,
  73                                   struct drm_private_state *state)
  74 {
  75         struct vc4_ctm_state *ctm_state = to_vc4_ctm_state(state);
  76
  77         kfree(ctm_state);
  78 }
  79
  80 static const struct drm_private_state_funcs vc4_ctm_state_funcs = {
  81         .atomic_duplicate_state = vc4_ctm_duplicate_state,
  82         .atomic_destroy_state = vc4_ctm_destroy_state,
  83 };
  84
  85 /* Converts a DRM S31.32 value to the HW S0.9 format. */
  86 static u16 vc4_ctm_s31_32_to_s0_9(u64 in)
  87 {
  88         u16 r;
  89
  90         /* Sign bit. */
  91         r = in & BIT_ULL(63) ? BIT(9) : 0;
  92
  93         if ((in & GENMASK_ULL(62, 32)) > 0) {
  94                 /* We have zero integer bits so we can only saturate here. */
  95                 r |= GENMASK(8, 0);
  96         } else {
  97                 /* Otherwise take the 9 most important fractional bits. */
  98                 r |= (in >> 23) & GENMASK(8, 0);
  99         }
 100
 101         return r;
 102 }
 103
 104 static void
 105 vc4_ctm_commit(struct vc4_dev *vc4, struct drm_atomic_state *state)
 106 {
 107         struct vc4_ctm_state *ctm_state = to_vc4_ctm_state(vc4->ctm_manager.state);
 108         struct drm_color_ctm *ctm = ctm_state->ctm;
 109
 110         if (ctm_state->fifo) {
 111                 HVS_WRITE(SCALER_OLEDCOEF2,
 112                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[0]),
 113                                         SCALER_OLEDCOEF2_R_TO_R) |
 114                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[3]),
 115                                         SCALER_OLEDCOEF2_R_TO_G) |
 116                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[6]),
 117                                         SCALER_OLEDCOEF2_R_TO_B));
 118                 HVS_WRITE(SCALER_OLEDCOEF1,
 119                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[1]),
 120                                         SCALER_OLEDCOEF1_G_TO_R) |
 121                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[4]),
 122                                         SCALER_OLEDCOEF1_G_TO_G) |
 123                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[7]),
 124                                         SCALER_OLEDCOEF1_G_TO_B));
 125                 HVS_WRITE(SCALER_OLEDCOEF0,
 126                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[2]),
 127                                         SCALER_OLEDCOEF0_B_TO_R) |
 128                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[5]),
 129                                         SCALER_OLEDCOEF0_B_TO_G) |
 130                           VC4_SET_FIELD(vc4_ctm_s31_32_to_s0_9(ctm->matrix[8]),
 131                                         SCALER_OLEDCOEF0_B_TO_B));
 132         }
 133
 134         HVS_WRITE(SCALER_OLEDOFFS,
 135                   VC4_SET_FIELD(ctm_state->fifo, SCALER_OLEDOFFS_DISPFIFO));
 136 }
 137
 138 static void
 139 vc4_atomic_complete_commit(struct drm_atomic_state *state)
 140 {
 141         struct drm_device *dev = state->dev;
 142         struct vc4_dev *vc4 = to_vc4_dev(dev);
 143
 144         drm_atomic_helper_wait_for_fences(dev, state, false);
 145
 146         drm_atomic_helper_wait_for_dependencies(state);
 147
 148         drm_atomic_helper_commit_modeset_disables(dev, state);
 149
 150         vc4_ctm_commit(vc4, state);
 151
 152         drm_atomic_helper_commit_planes(dev, state, 0);
 153
 154         drm_atomic_helper_commit_modeset_enables(dev, state);
 155
 156         drm_atomic_helper_fake_vblank(state);
 157
 158         drm_atomic_helper_commit_hw_done(state);
 159
 160         drm_atomic_helper_wait_for_flip_done(dev, state);
 161
 162         drm_atomic_helper_cleanup_planes(dev, state);
 163
 164         drm_atomic_helper_commit_cleanup_done(state);
 165
 166         drm_atomic_state_put(state);
 167
 168         up(&vc4->async_modeset);
 169 }
 170
 171 static void commit_work(struct work_struct *work)
 172 {
 173         struct drm_atomic_state *state = container_of(work,
 174                                                       struct drm_atomic_state,
 175                                                       commit_work);
 176         vc4_atomic_complete_commit(state);
 177 }
 178
 179 /**
 180  * vc4_atomic_commit - commit validated state object
 181  * @dev: DRM device
 182  * @state: the driver state object
 183  * @nonblock: nonblocking commit
 184  *
 185  * This function commits a with drm_atomic_helper_check() pre-validated state
 186  * object. This can still fail when e.g. the framebuffer reservation fails. For
 187  * now this doesn't implement asynchronous commits.
 188  *
 189  * RETURNS
 190  * Zero for success or -errno.
 191  */
 192 static int vc4_atomic_commit(struct drm_device *dev,
 193                              struct drm_atomic_state *state,
 194                              bool nonblock)
 195 {
 196         struct vc4_dev *vc4 = to_vc4_dev(dev);
 197         int ret;
 198
 199         if (state->async_update) {
 200                 ret = down_interruptible(&vc4->async_modeset);
 201                 if (ret)
 202                         return ret;
 203
 204                 ret = drm_atomic_helper_prepare_planes(dev, state);
 205                 if (ret) {
 206                         up(&vc4->async_modeset);
 207                         return ret;
 208                 }
 209
 210                 drm_atomic_helper_async_commit(dev, state);
 211
 212                 drm_atomic_helper_cleanup_planes(dev, state);
 213
 214                 up(&vc4->async_modeset);
 215
 216                 return 0;
 217         }
 218
 219         /* We know for sure we don't want an async update here. Set
 220          * state->legacy_cursor_update to false to prevent
 221          * drm_atomic_helper_setup_commit() from auto-completing
 222          * commit->flip_done.
 223          */
 224         state->legacy_cursor_update = false;
 225         ret = drm_atomic_helper_setup_commit(state, nonblock);
 226         if (ret)
 227                 return ret;
 228
 229         INIT_WORK(&state->commit_work, commit_work);
 230
 231         ret = down_interruptible(&vc4->async_modeset);
 232         if (ret)
 233                 return ret;
 234
 235         ret = drm_atomic_helper_prepare_planes(dev, state);
 236         if (ret) {
 237                 up(&vc4->async_modeset);
 238                 return ret;
 239         }
 240
 241         if (!nonblock) {
 242                 ret = drm_atomic_helper_wait_for_fences(dev, state, true);
 243                 if (ret) {
 244                         drm_atomic_helper_cleanup_planes(dev, state);
 245                         up(&vc4->async_modeset);
 246                         return ret;
 247                 }
 248         }
 249
 250         /*
 251          * This is the point of no return - everything below never fails except
 252          * when the hw goes bonghits. Which means we can commit the new state on
 253          * the software side now.
 254          */
 255
 256         BUG_ON(drm_atomic_helper_swap_state(state, false) < 0);
 257
 258         /*
 259          * Everything below can be run asynchronously without the need to grab
 260          * any modeset locks at all under one condition: It must be guaranteed
 261          * that the asynchronous work has either been cancelled (if the driver
 262          * supports it, which at least requires that the framebuffers get
 263          * cleaned up with drm_atomic_helper_cleanup_planes()) or completed
 264          * before the new state gets committed on the software side with
 265          * drm_atomic_helper_swap_state().
 266          *
 267          * This scheme allows new atomic state updates to be prepared and
 268          * checked in parallel to the asynchronous completion of the previous
 269          * update. Which is important since compositors need to figure out the
 270          * composition of the next frame right after having submitted the
 271          * current layout.
 272          */
 273
 274         drm_atomic_state_get(state);
 275         if (nonblock)
 276                 queue_work(system_unbound_wq, &state->commit_work);
 277         else
 278                 vc4_atomic_complete_commit(state);
 279
 280         return 0;
 281 }
 282
 283 static struct drm_framebuffer *vc4_fb_create(struct drm_device *dev,
 284                                              struct drm_file *file_priv,
 285                                              const struct drm_mode_fb_cmd2 *mode_cmd)
 286 {
 287         struct drm_mode_fb_cmd2 mode_cmd_local;
 288
 289         /* If the user didn't specify a modifier, use the
 290          * vc4_set_tiling_ioctl() state for the BO.
 291          */
 292         if (!(mode_cmd->flags & DRM_MODE_FB_MODIFIERS)) {
 293                 struct drm_gem_object *gem_obj;
 294                 struct vc4_bo *bo;
 295
 296                 gem_obj = drm_gem_object_lookup(file_priv,
 297                                                 mode_cmd->handles[0]);
 298                 if (!gem_obj) {
 299                         DRM_DEBUG("Failed to look up GEM BO %d\n",
 300                                   mode_cmd->handles[0]);
 301                         return ERR_PTR(-ENOENT);
 302                 }
 303                 bo = to_vc4_bo(gem_obj);
 304
 305                 mode_cmd_local = *mode_cmd;
 306
 307                 if (bo->t_format) {
 308                         mode_cmd_local.modifier[0] =
 309                                 DRM_FORMAT_MOD_BROADCOM_VC4_T_TILED;
 310                 } else {
 311                         mode_cmd_local.modifier[0] = DRM_FORMAT_MOD_NONE;
 312                 }
 313
 314                 drm_gem_object_put_unlocked(gem_obj);
 315
 316                 mode_cmd = &mode_cmd_local;
 317         }
 318
 319         return drm_gem_fb_create(dev, file_priv, mode_cmd);
 320 }
 321
 322 /* Our CTM has some peculiar limitations: we can only enable it for one CRTC
 323  * at a time and the HW only supports S0.9 scalars. To account for the latter,
 324  * we don't allow userland to set a CTM that we have no hope of approximating.
 325  */
 326 static int
 327 vc4_ctm_atomic_check(struct drm_device *dev, struct drm_atomic_state *state)
 328 {
 329         struct vc4_dev *vc4 = to_vc4_dev(dev);
 330         struct vc4_ctm_state *ctm_state = NULL;
 331         struct drm_crtc *crtc;
 332         struct drm_crtc_state *old_crtc_state, *new_crtc_state;
 333         struct drm_color_ctm *ctm;
 334         int i;
 335
 336         for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) {
 337                 /* CTM is being disabled. */
 338                 if (!new_crtc_state->ctm && old_crtc_state->ctm) {
 339                         ctm_state = vc4_get_ctm_state(state, &vc4->ctm_manager);
 340                         if (IS_ERR(ctm_state))
 341                                 return PTR_ERR(ctm_state);
 342                         ctm_state->fifo = 0;
 343                 }
 344         }
 345
 346         for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) {
 347                 if (new_crtc_state->ctm == old_crtc_state->ctm)
 348                         continue;
 349
 350                 if (!ctm_state) {
 351                         ctm_state = vc4_get_ctm_state(state, &vc4->ctm_manager);
 352                         if (IS_ERR(ctm_state))
 353                                 return PTR_ERR(ctm_state);
 354                 }
 355
 356                 /* CTM is being enabled or the matrix changed. */
 357                 if (new_crtc_state->ctm) {
 358                         /* fifo is 1-based since 0 disables CTM. */
 359                         int fifo = to_vc4_crtc(crtc)->channel + 1;
 360
 361                         /* Check userland isn't trying to turn on CTM for more
 362                          * than one CRTC at a time.
 363                          */
 364                         if (ctm_state->fifo && ctm_state->fifo != fifo) {
 365                                 DRM_DEBUG_DRIVER("Too many CTM configured\n");
 366                                 return -EINVAL;
 367                         }
 368
 369                         /* Check we can approximate the specified CTM.
 370                          * We disallow scalars |c| > 1.0 since the HW has
 371                          * no integer bits.
 372                          */
 373                         ctm = new_crtc_state->ctm->data;
 374                         for (i = 0; i < ARRAY_SIZE(ctm->matrix); i++) {
 375                                 u64 val = ctm->matrix[i];
 376
 377                                 val &= ~BIT_ULL(63);
 378                                 if (val > BIT_ULL(32))
 379                                         return -EINVAL;
 380                         }
 381
 382                         ctm_state->fifo = fifo;
 383                         ctm_state->ctm = ctm;
 384                 }
 385         }
 386
 387         return 0;
 388 }
 389
 390 static int
 391 vc4_atomic_check(struct drm_device *dev, struct drm_atomic_state *state)
 392 {
 393         int ret;
 394
 395         ret = vc4_ctm_atomic_check(dev, state);
 396         if (ret < 0)
 397                 return ret;
 398
 399         return drm_atomic_helper_check(dev, state);
 400 }
 401
 402 static const struct drm_mode_config_funcs vc4_mode_funcs = {
 403         .output_poll_changed = drm_fb_helper_output_poll_changed,
 404         .atomic_check = vc4_atomic_check,
 405         .atomic_commit = vc4_atomic_commit,
 406         .fb_create = vc4_fb_create,
 407 };
 408
 409 int vc4_kms_load(struct drm_device *dev)
 410 {
 411         struct vc4_dev *vc4 = to_vc4_dev(dev);
 412         struct vc4_ctm_state *ctm_state;
 413         int ret;
 414
 415         sema_init(&vc4->async_modeset, 1);
 416
 417         /* Set support for vblank irq fast disable, before drm_vblank_init() */
 418         dev->vblank_disable_immediate = true;
 419
 420         ret = drm_vblank_init(dev, dev->mode_config.num_crtc);
 421         if (ret < 0) {
 422                 dev_err(dev->dev, "failed to initialize vblank\n");
 423                 return ret;
 424         }
 425
 426         dev->mode_config.max_width = 2048;
 427         dev->mode_config.max_height = 2048;
 428         dev->mode_config.funcs = &vc4_mode_funcs;
 429         dev->mode_config.preferred_depth = 24;
 430         dev->mode_config.async_page_flip = true;
 431         dev->mode_config.allow_fb_modifiers = true;
 432
 433         drm_modeset_lock_init(&vc4->ctm_state_lock);
 434
 435         ctm_state = kzalloc(sizeof(*ctm_state), GFP_KERNEL);
 436         if (!ctm_state)
 437                 return -ENOMEM;
 438         drm_atomic_private_obj_init(&vc4->ctm_manager, &ctm_state->base,
 439                                     &vc4_ctm_state_funcs);
 440
 441         drm_mode_config_reset(dev);
 442
 443         if (dev->mode_config.num_connector)
 444                 drm_fb_cma_fbdev_init(dev, 32, 0);
 445
 446         drm_kms_helper_poll_init(dev);
 447
 448         return 0;
 449 }