1/*
   2 * Copyright (c) 2006-2009 Red Hat Inc.
   3 * Copyright (c) 2006-2008 Intel Corporation
   4 * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
   5 *
   6 * DRM framebuffer helper functions
   7 *
   8 * Permission to use, copy, modify, distribute, and sell this software and its
   9 * documentation for any purpose is hereby granted without fee, provided that
  10 * the above copyright notice appear in all copies and that both that copyright
  11 * notice and this permission notice appear in supporting documentation, and
  12 * that the name of the copyright holders not be used in advertising or
  13 * publicity pertaining to distribution of the software without specific,
  14 * written prior permission.  The copyright holders make no representations
  15 * about the suitability of this software for any purpose.  It is provided "as
  16 * is" without express or implied warranty.
  17 *
  18 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  19 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
  20 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
  21 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
  22 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
  23 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
  24 * OF THIS SOFTWARE.
  25 *
  26 * Authors:
  27 *      Dave Airlie <airlied@linux.ie>
  28 *      Jesse Barnes <jesse.barnes@intel.com>
  29 */
  30#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  31
  32#include <linux/console.h>
  33#include <linux/pci.h>
  34#include <linux/sysrq.h>
  35#include <linux/vga_switcheroo.h>
  36
  37#include <drm/drm_atomic.h>
  38#include <drm/drm_drv.h>
  39#include <drm/drm_fb_helper.h>
  40#include <drm/drm_fourcc.h>
  41#include <drm/drm_framebuffer.h>
  42#include <drm/drm_modeset_helper_vtables.h>
  43#include <drm/drm_print.h>
  44#include <drm/drm_vblank.h>
  45
  46#include "drm_internal.h"
  47
  48static bool drm_fbdev_emulation = true;
  49module_param_named(fbdev_emulation, drm_fbdev_emulation, bool, 0600);
  50MODULE_PARM_DESC(fbdev_emulation,
  51		 "Enable legacy fbdev emulation [default=true]");
  52
  53static int drm_fbdev_overalloc = CONFIG_DRM_FBDEV_OVERALLOC;
  54module_param(drm_fbdev_overalloc, int, 0444);
  55MODULE_PARM_DESC(drm_fbdev_overalloc,
  56		 "Overallocation of the fbdev buffer (%) [default="
  57		 __MODULE_STRING(CONFIG_DRM_FBDEV_OVERALLOC) "]");
  58
  59/*
  60 * In order to keep user-space compatibility, we want in certain use-cases
  61 * to keep leaking the fbdev physical address to the user-space program
  62 * handling the fbdev buffer.
  63 *
  64 * This is a bad habit, essentially kept to support closed-source OpenGL
  65 * drivers that should really be moved into open-source upstream projects
  66 * instead of using legacy physical addresses in user space to communicate
  67 * with other out-of-tree kernel modules.
  68 *
  69 * This module_param *should* be removed as soon as possible and be
  70 * considered as a broken and legacy behaviour from a modern fbdev device.
  71 */
  72static bool drm_leak_fbdev_smem;
  73#if IS_ENABLED(CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM)
 
  74module_param_unsafe(drm_leak_fbdev_smem, bool, 0600);
  75MODULE_PARM_DESC(drm_leak_fbdev_smem,
  76		 "Allow unsafe leaking fbdev physical smem address [default=false]");
  77#endif
  78
  79static LIST_HEAD(kernel_fb_helper_list);
  80static DEFINE_MUTEX(kernel_fb_helper_lock);
  81
  82/**
  83 * DOC: fbdev helpers
  84 *
  85 * The fb helper functions are useful to provide an fbdev on top of a drm kernel
  86 * mode setting driver. They can be used mostly independently from the crtc
  87 * helper functions used by many drivers to implement the kernel mode setting
  88 * interfaces.
  89 *
  90 * Drivers that support a dumb buffer with a virtual address and mmap support,
  91 * should try out the generic fbdev emulation using drm_fbdev_generic_setup().
  92 * It will automatically set up deferred I/O if the driver requires a shadow
  93 * buffer.
  94 *
  95 * Existing fbdev implementations should restore the fbdev console by using
  96 * drm_fb_helper_lastclose() as their &drm_driver.lastclose callback.
  97 * They should also notify the fb helper code from updates to the output
  98 * configuration by using drm_fb_helper_output_poll_changed() as their
  99 * &drm_mode_config_funcs.output_poll_changed callback. New implementations
 100 * of fbdev should be build on top of struct &drm_client_funcs, which handles
 101 * this automatically. Setting the old callbacks should be avoided.
 102 *
 103 * For suspend/resume consider using drm_mode_config_helper_suspend() and
 104 * drm_mode_config_helper_resume() which takes care of fbdev as well.
 105 *
 106 * All other functions exported by the fb helper library can be used to
 107 * implement the fbdev driver interface by the driver.
 108 *
 109 * It is possible, though perhaps somewhat tricky, to implement race-free
 110 * hotplug detection using the fbdev helpers. The drm_fb_helper_prepare()
 111 * helper must be called first to initialize the minimum required to make
 112 * hotplug detection work. Drivers also need to make sure to properly set up
 113 * the &drm_mode_config.funcs member. After calling drm_kms_helper_poll_init()
 114 * it is safe to enable interrupts and start processing hotplug events. At the
 115 * same time, drivers should initialize all modeset objects such as CRTCs,
 116 * encoders and connectors. To finish up the fbdev helper initialization, the
 117 * drm_fb_helper_init() function is called. To probe for all attached displays
 118 * and set up an initial configuration using the detected hardware, drivers
 119 * should call drm_fb_helper_initial_config().
 120 *
 121 * If &drm_framebuffer_funcs.dirty is set, the
 122 * drm_fb_helper_{cfb,sys}_{write,fillrect,copyarea,imageblit} functions will
 123 * accumulate changes and schedule &drm_fb_helper.dirty_work to run right
 124 * away. This worker then calls the dirty() function ensuring that it will
 125 * always run in process context since the fb_*() function could be running in
 126 * atomic context. If drm_fb_helper_deferred_io() is used as the deferred_io
 127 * callback it will also schedule dirty_work with the damage collected from the
 128 * mmap page writes.
 129 *
 130 * Deferred I/O is not compatible with SHMEM. Such drivers should request an
 131 * fbdev shadow buffer and call drm_fbdev_generic_setup() instead.
 132 */
 133
 134static void drm_fb_helper_restore_lut_atomic(struct drm_crtc *crtc)
 135{
 136	uint16_t *r_base, *g_base, *b_base;
 137
 138	if (crtc->funcs->gamma_set == NULL)
 139		return;
 140
 141	r_base = crtc->gamma_store;
 142	g_base = r_base + crtc->gamma_size;
 143	b_base = g_base + crtc->gamma_size;
 144
 145	crtc->funcs->gamma_set(crtc, r_base, g_base, b_base,
 146			       crtc->gamma_size, NULL);
 147}
 148
 149/**
 150 * drm_fb_helper_debug_enter - implementation for &fb_ops.fb_debug_enter
 151 * @info: fbdev registered by the helper
 152 */
 153int drm_fb_helper_debug_enter(struct fb_info *info)
 154{
 155	struct drm_fb_helper *helper = info->par;
 156	const struct drm_crtc_helper_funcs *funcs;
 157	struct drm_mode_set *mode_set;
 158
 159	list_for_each_entry(helper, &kernel_fb_helper_list, kernel_fb_list) {
 160		mutex_lock(&helper->client.modeset_mutex);
 161		drm_client_for_each_modeset(mode_set, &helper->client) {
 162			if (!mode_set->crtc->enabled)
 163				continue;
 164
 165			funcs =	mode_set->crtc->helper_private;
 166			if (funcs->mode_set_base_atomic == NULL)
 167				continue;
 168
 169			if (drm_drv_uses_atomic_modeset(mode_set->crtc->dev))
 170				continue;
 171
 172			funcs->mode_set_base_atomic(mode_set->crtc,
 173						    mode_set->fb,
 174						    mode_set->x,
 175						    mode_set->y,
 176						    ENTER_ATOMIC_MODE_SET);
 177		}
 178		mutex_unlock(&helper->client.modeset_mutex);
 179	}
 180
 181	return 0;
 182}
 183EXPORT_SYMBOL(drm_fb_helper_debug_enter);
 184
 185/**
 186 * drm_fb_helper_debug_leave - implementation for &fb_ops.fb_debug_leave
 187 * @info: fbdev registered by the helper
 188 */
 189int drm_fb_helper_debug_leave(struct fb_info *info)
 190{
 191	struct drm_fb_helper *helper = info->par;
 192	struct drm_client_dev *client = &helper->client;
 193	struct drm_device *dev = helper->dev;
 194	struct drm_crtc *crtc;
 195	const struct drm_crtc_helper_funcs *funcs;
 196	struct drm_mode_set *mode_set;
 197	struct drm_framebuffer *fb;
 198
 199	mutex_lock(&client->modeset_mutex);
 200	drm_client_for_each_modeset(mode_set, client) {
 201		crtc = mode_set->crtc;
 202		if (drm_drv_uses_atomic_modeset(crtc->dev))
 203			continue;
 204
 205		funcs = crtc->helper_private;
 206		fb = crtc->primary->fb;
 207
 208		if (!crtc->enabled)
 209			continue;
 210
 211		if (!fb) {
 212			drm_err(dev, "no fb to restore?\n");
 213			continue;
 214		}
 215
 216		if (funcs->mode_set_base_atomic == NULL)
 217			continue;
 218
 219		drm_fb_helper_restore_lut_atomic(mode_set->crtc);
 220		funcs->mode_set_base_atomic(mode_set->crtc, fb, crtc->x,
 221					    crtc->y, LEAVE_ATOMIC_MODE_SET);
 222	}
 223	mutex_unlock(&client->modeset_mutex);
 224
 225	return 0;
 226}
 227EXPORT_SYMBOL(drm_fb_helper_debug_leave);
 228
 229static int
 230__drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper,
 231					    bool force)
 232{
 233	bool do_delayed;
 234	int ret;
 235
 236	if (!drm_fbdev_emulation || !fb_helper)
 237		return -ENODEV;
 238
 239	if (READ_ONCE(fb_helper->deferred_setup))
 240		return 0;
 241
 242	mutex_lock(&fb_helper->lock);
 243	if (force) {
 244		/*
 245		 * Yes this is the _locked version which expects the master lock
 246		 * to be held. But for forced restores we're intentionally
 247		 * racing here, see drm_fb_helper_set_par().
 248		 */
 249		ret = drm_client_modeset_commit_locked(&fb_helper->client);
 250	} else {
 251		ret = drm_client_modeset_commit(&fb_helper->client);
 252	}
 253
 254	do_delayed = fb_helper->delayed_hotplug;
 255	if (do_delayed)
 256		fb_helper->delayed_hotplug = false;
 257	mutex_unlock(&fb_helper->lock);
 258
 259	if (do_delayed)
 260		drm_fb_helper_hotplug_event(fb_helper);
 261
 262	return ret;
 263}
 264
 265/**
 266 * drm_fb_helper_restore_fbdev_mode_unlocked - restore fbdev configuration
 267 * @fb_helper: driver-allocated fbdev helper, can be NULL
 268 *
 269 * This should be called from driver's drm &drm_driver.lastclose callback
 270 * when implementing an fbcon on top of kms using this helper. This ensures that
 271 * the user isn't greeted with a black screen when e.g. X dies.
 272 *
 273 * RETURNS:
 274 * Zero if everything went ok, negative error code otherwise.
 275 */
 276int drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper)
 277{
 278	return __drm_fb_helper_restore_fbdev_mode_unlocked(fb_helper, false);
 279}
 280EXPORT_SYMBOL(drm_fb_helper_restore_fbdev_mode_unlocked);
 281
 282#ifdef CONFIG_MAGIC_SYSRQ
 283/* emergency restore, don't bother with error reporting */
 284static void drm_fb_helper_restore_work_fn(struct work_struct *ignored)
 285{
 286	struct drm_fb_helper *helper;
 287
 288	mutex_lock(&kernel_fb_helper_lock);
 289	list_for_each_entry(helper, &kernel_fb_helper_list, kernel_fb_list) {
 290		struct drm_device *dev = helper->dev;
 291
 292		if (dev->switch_power_state == DRM_SWITCH_POWER_OFF)
 293			continue;
 294
 295		mutex_lock(&helper->lock);
 296		drm_client_modeset_commit_locked(&helper->client);
 297		mutex_unlock(&helper->lock);
 298	}
 299	mutex_unlock(&kernel_fb_helper_lock);
 300}
 301
 302static DECLARE_WORK(drm_fb_helper_restore_work, drm_fb_helper_restore_work_fn);
 303
 304static void drm_fb_helper_sysrq(u8 dummy1)
 305{
 306	schedule_work(&drm_fb_helper_restore_work);
 307}
 308
 309static const struct sysrq_key_op sysrq_drm_fb_helper_restore_op = {
 310	.handler = drm_fb_helper_sysrq,
 311	.help_msg = "force-fb(v)",
 312	.action_msg = "Restore framebuffer console",
 313};
 314#else
 315static const struct sysrq_key_op sysrq_drm_fb_helper_restore_op = { };
 316#endif
 317
 318static void drm_fb_helper_dpms(struct fb_info *info, int dpms_mode)
 319{
 320	struct drm_fb_helper *fb_helper = info->par;
 321
 322	mutex_lock(&fb_helper->lock);
 323	drm_client_modeset_dpms(&fb_helper->client, dpms_mode);
 324	mutex_unlock(&fb_helper->lock);
 325}
 326
 327/**
 328 * drm_fb_helper_blank - implementation for &fb_ops.fb_blank
 329 * @blank: desired blanking state
 330 * @info: fbdev registered by the helper
 331 */
 332int drm_fb_helper_blank(int blank, struct fb_info *info)
 333{
 334	if (oops_in_progress)
 335		return -EBUSY;
 336
 337	switch (blank) {
 338	/* Display: On; HSync: On, VSync: On */
 339	case FB_BLANK_UNBLANK:
 340		drm_fb_helper_dpms(info, DRM_MODE_DPMS_ON);
 341		break;
 342	/* Display: Off; HSync: On, VSync: On */
 343	case FB_BLANK_NORMAL:
 344		drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY);
 345		break;
 346	/* Display: Off; HSync: Off, VSync: On */
 347	case FB_BLANK_HSYNC_SUSPEND:
 348		drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY);
 349		break;
 350	/* Display: Off; HSync: On, VSync: Off */
 351	case FB_BLANK_VSYNC_SUSPEND:
 352		drm_fb_helper_dpms(info, DRM_MODE_DPMS_SUSPEND);
 353		break;
 354	/* Display: Off; HSync: Off, VSync: Off */
 355	case FB_BLANK_POWERDOWN:
 356		drm_fb_helper_dpms(info, DRM_MODE_DPMS_OFF);
 357		break;
 358	}
 359	return 0;
 360}
 361EXPORT_SYMBOL(drm_fb_helper_blank);
 362
 363static void drm_fb_helper_resume_worker(struct work_struct *work)
 364{
 365	struct drm_fb_helper *helper = container_of(work, struct drm_fb_helper,
 366						    resume_work);
 367
 368	console_lock();
 369	fb_set_suspend(helper->info, 0);
 370	console_unlock();
 371}
 372
 373static void drm_fb_helper_fb_dirty(struct drm_fb_helper *helper)
 374{
 375	struct drm_device *dev = helper->dev;
 376	struct drm_clip_rect *clip = &helper->damage_clip;
 377	struct drm_clip_rect clip_copy;
 378	unsigned long flags;
 379	int ret;
 380
 381	if (drm_WARN_ON_ONCE(dev, !helper->funcs->fb_dirty))
 382		return;
 383
 384	spin_lock_irqsave(&helper->damage_lock, flags);
 385	clip_copy = *clip;
 386	clip->x1 = clip->y1 = ~0;
 387	clip->x2 = clip->y2 = 0;
 388	spin_unlock_irqrestore(&helper->damage_lock, flags);
 389
 390	ret = helper->funcs->fb_dirty(helper, &clip_copy);
 391	if (ret)
 392		goto err;
 393
 394	return;
 395
 396err:
 397	/*
 398	 * Restore damage clip rectangle on errors. The next run
 399	 * of the damage worker will perform the update.
 400	 */
 401	spin_lock_irqsave(&helper->damage_lock, flags);
 402	clip->x1 = min_t(u32, clip->x1, clip_copy.x1);
 403	clip->y1 = min_t(u32, clip->y1, clip_copy.y1);
 404	clip->x2 = max_t(u32, clip->x2, clip_copy.x2);
 405	clip->y2 = max_t(u32, clip->y2, clip_copy.y2);
 406	spin_unlock_irqrestore(&helper->damage_lock, flags);
 407}
 408
 409static void drm_fb_helper_damage_work(struct work_struct *work)
 410{
 411	struct drm_fb_helper *helper = container_of(work, struct drm_fb_helper, damage_work);
 412
 413	drm_fb_helper_fb_dirty(helper);
 414}
 415
 416/**
 417 * drm_fb_helper_prepare - setup a drm_fb_helper structure
 418 * @dev: DRM device
 419 * @helper: driver-allocated fbdev helper structure to set up
 420 * @preferred_bpp: Preferred bits per pixel for the device.
 421 * @funcs: pointer to structure of functions associate with this helper
 422 *
 423 * Sets up the bare minimum to make the framebuffer helper usable. This is
 424 * useful to implement race-free initialization of the polling helpers.
 425 */
 426void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper,
 427			   unsigned int preferred_bpp,
 428			   const struct drm_fb_helper_funcs *funcs)
 429{
 430	/*
 431	 * Pick a preferred bpp of 32 if no value has been given. This
 432	 * will select XRGB8888 for the framebuffer formats. All drivers
 433	 * have to support XRGB8888 for backwards compatibility with legacy
 434	 * userspace, so it's the safe choice here.
 435	 *
 436	 * TODO: Replace struct drm_mode_config.preferred_depth and this
 437	 *       bpp value with a preferred format that is given as struct
 438	 *       drm_format_info. Then derive all other values from the
 439	 *       format.
 440	 */
 441	if (!preferred_bpp)
 442		preferred_bpp = 32;
 443
 444	INIT_LIST_HEAD(&helper->kernel_fb_list);
 445	spin_lock_init(&helper->damage_lock);
 446	INIT_WORK(&helper->resume_work, drm_fb_helper_resume_worker);
 447	INIT_WORK(&helper->damage_work, drm_fb_helper_damage_work);
 448	helper->damage_clip.x1 = helper->damage_clip.y1 = ~0;
 449	mutex_init(&helper->lock);
 450	helper->funcs = funcs;
 451	helper->dev = dev;
 452	helper->preferred_bpp = preferred_bpp;
 453}
 454EXPORT_SYMBOL(drm_fb_helper_prepare);
 455
 456/**
 457 * drm_fb_helper_unprepare - clean up a drm_fb_helper structure
 458 * @fb_helper: driver-allocated fbdev helper structure to set up
 459 *
 460 * Cleans up the framebuffer helper. Inverse of drm_fb_helper_prepare().
 461 */
 462void drm_fb_helper_unprepare(struct drm_fb_helper *fb_helper)
 463{
 464	mutex_destroy(&fb_helper->lock);
 465}
 466EXPORT_SYMBOL(drm_fb_helper_unprepare);
 467
 468/**
 469 * drm_fb_helper_init - initialize a &struct drm_fb_helper
 470 * @dev: drm device
 471 * @fb_helper: driver-allocated fbdev helper structure to initialize
 472 *
 473 * This allocates the structures for the fbdev helper with the given limits.
 474 * Note that this won't yet touch the hardware (through the driver interfaces)
 475 * nor register the fbdev. This is only done in drm_fb_helper_initial_config()
 476 * to allow driver writes more control over the exact init sequence.
 477 *
 478 * Drivers must call drm_fb_helper_prepare() before calling this function.
 479 *
 480 * RETURNS:
 481 * Zero if everything went ok, nonzero otherwise.
 482 */
 483int drm_fb_helper_init(struct drm_device *dev,
 484		       struct drm_fb_helper *fb_helper)
 485{
 486	int ret;
 487
 488	/*
 489	 * If this is not the generic fbdev client, initialize a drm_client
 490	 * without callbacks so we can use the modesets.
 491	 */
 492	if (!fb_helper->client.funcs) {
 493		ret = drm_client_init(dev, &fb_helper->client, "drm_fb_helper", NULL);
 494		if (ret)
 495			return ret;
 496	}
 497
 498	dev->fb_helper = fb_helper;
 499
 500	return 0;
 501}
 502EXPORT_SYMBOL(drm_fb_helper_init);
 503
 504/**
 505 * drm_fb_helper_alloc_info - allocate fb_info and some of its members
 506 * @fb_helper: driver-allocated fbdev helper
 507 *
 508 * A helper to alloc fb_info and the member cmap. Called by the driver
 509 * within the fb_probe fb_helper callback function. Drivers do not
 510 * need to release the allocated fb_info structure themselves, this is
 511 * automatically done when calling drm_fb_helper_fini().
 512 *
 513 * RETURNS:
 514 * fb_info pointer if things went okay, pointer containing error code
 515 * otherwise
 516 */
 517struct fb_info *drm_fb_helper_alloc_info(struct drm_fb_helper *fb_helper)
 518{
 519	struct device *dev = fb_helper->dev->dev;
 520	struct fb_info *info;
 521	int ret;
 522
 523	info = framebuffer_alloc(0, dev);
 524	if (!info)
 525		return ERR_PTR(-ENOMEM);
 526
 527	ret = fb_alloc_cmap(&info->cmap, 256, 0);
 528	if (ret)
 529		goto err_release;
 530
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 531	fb_helper->info = info;
 532	info->skip_vt_switch = true;
 533
 534	return info;
 535
 
 
 536err_release:
 537	framebuffer_release(info);
 538	return ERR_PTR(ret);
 539}
 540EXPORT_SYMBOL(drm_fb_helper_alloc_info);
 541
 542/**
 543 * drm_fb_helper_release_info - release fb_info and its members
 544 * @fb_helper: driver-allocated fbdev helper
 545 *
 546 * A helper to release fb_info and the member cmap.  Drivers do not
 547 * need to release the allocated fb_info structure themselves, this is
 548 * automatically done when calling drm_fb_helper_fini().
 549 */
 550void drm_fb_helper_release_info(struct drm_fb_helper *fb_helper)
 551{
 552	struct fb_info *info = fb_helper->info;
 553
 554	if (!info)
 555		return;
 556
 557	fb_helper->info = NULL;
 558
 559	if (info->cmap.len)
 560		fb_dealloc_cmap(&info->cmap);
 561	framebuffer_release(info);
 562}
 563EXPORT_SYMBOL(drm_fb_helper_release_info);
 564
 565/**
 566 * drm_fb_helper_unregister_info - unregister fb_info framebuffer device
 567 * @fb_helper: driver-allocated fbdev helper, can be NULL
 568 *
 569 * A wrapper around unregister_framebuffer, to release the fb_info
 570 * framebuffer device. This must be called before releasing all resources for
 571 * @fb_helper by calling drm_fb_helper_fini().
 572 */
 573void drm_fb_helper_unregister_info(struct drm_fb_helper *fb_helper)
 574{
 575	if (fb_helper && fb_helper->info)
 576		unregister_framebuffer(fb_helper->info);
 577}
 578EXPORT_SYMBOL(drm_fb_helper_unregister_info);
 579
 580/**
 581 * drm_fb_helper_fini - finialize a &struct drm_fb_helper
 582 * @fb_helper: driver-allocated fbdev helper, can be NULL
 583 *
 584 * This cleans up all remaining resources associated with @fb_helper.
 585 */
 586void drm_fb_helper_fini(struct drm_fb_helper *fb_helper)
 587{
 
 
 588	if (!fb_helper)
 589		return;
 590
 591	fb_helper->dev->fb_helper = NULL;
 592
 593	if (!drm_fbdev_emulation)
 594		return;
 595
 596	cancel_work_sync(&fb_helper->resume_work);
 597	cancel_work_sync(&fb_helper->damage_work);
 598
 599	drm_fb_helper_release_info(fb_helper);
 
 
 
 
 
 
 600
 601	mutex_lock(&kernel_fb_helper_lock);
 602	if (!list_empty(&fb_helper->kernel_fb_list)) {
 603		list_del(&fb_helper->kernel_fb_list);
 604		if (list_empty(&kernel_fb_helper_list))
 605			unregister_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
 606	}
 607	mutex_unlock(&kernel_fb_helper_lock);
 608
 
 
 609	if (!fb_helper->client.funcs)
 610		drm_client_release(&fb_helper->client);
 611}
 612EXPORT_SYMBOL(drm_fb_helper_fini);
 613
 614static void drm_fb_helper_add_damage_clip(struct drm_fb_helper *helper, u32 x, u32 y,
 615					  u32 width, u32 height)
 616{
 617	struct drm_clip_rect *clip = &helper->damage_clip;
 618	unsigned long flags;
 619
 620	spin_lock_irqsave(&helper->damage_lock, flags);
 621	clip->x1 = min_t(u32, clip->x1, x);
 622	clip->y1 = min_t(u32, clip->y1, y);
 623	clip->x2 = max_t(u32, clip->x2, x + width);
 624	clip->y2 = max_t(u32, clip->y2, y + height);
 625	spin_unlock_irqrestore(&helper->damage_lock, flags);
 626}
 627
 628static void drm_fb_helper_damage(struct drm_fb_helper *helper, u32 x, u32 y,
 629				 u32 width, u32 height)
 630{
 631	drm_fb_helper_add_damage_clip(helper, x, y, width, height);
 632
 633	schedule_work(&helper->damage_work);
 634}
 635
 636/*
 637 * Convert memory region into area of scanlines and pixels per
 638 * scanline. The parameters off and len must not reach beyond
 639 * the end of the framebuffer.
 640 */
 641static void drm_fb_helper_memory_range_to_clip(struct fb_info *info, off_t off, size_t len,
 642					       struct drm_rect *clip)
 643{
 644	u32 line_length = info->fix.line_length;
 645	u32 fb_height = info->var.yres;
 646	off_t end = off + len;
 647	u32 x1 = 0;
 648	u32 y1 = off / line_length;
 649	u32 x2 = info->var.xres;
 650	u32 y2 = DIV_ROUND_UP(end, line_length);
 651
 652	/* Don't allow any of them beyond the bottom bound of display area */
 653	if (y1 > fb_height)
 654		y1 = fb_height;
 655	if (y2 > fb_height)
 656		y2 = fb_height;
 657
 658	if ((y2 - y1) == 1) {
 659		/*
 660		 * We've only written to a single scanline. Try to reduce
 661		 * the number of horizontal pixels that need an update.
 662		 */
 663		off_t bit_off = (off % line_length) * 8;
 664		off_t bit_end = (end % line_length) * 8;
 665
 666		x1 = bit_off / info->var.bits_per_pixel;
 667		x2 = DIV_ROUND_UP(bit_end, info->var.bits_per_pixel);
 668	}
 669
 670	drm_rect_init(clip, x1, y1, x2 - x1, y2 - y1);
 671}
 672
 673/* Don't use in new code. */
 674void drm_fb_helper_damage_range(struct fb_info *info, off_t off, size_t len)
 675{
 676	struct drm_fb_helper *fb_helper = info->par;
 677	struct drm_rect damage_area;
 678
 679	drm_fb_helper_memory_range_to_clip(info, off, len, &damage_area);
 680	drm_fb_helper_damage(fb_helper, damage_area.x1, damage_area.y1,
 681			     drm_rect_width(&damage_area),
 682			     drm_rect_height(&damage_area));
 683}
 684EXPORT_SYMBOL(drm_fb_helper_damage_range);
 685
 686/* Don't use in new code. */
 687void drm_fb_helper_damage_area(struct fb_info *info, u32 x, u32 y, u32 width, u32 height)
 688{
 689	struct drm_fb_helper *fb_helper = info->par;
 690
 691	drm_fb_helper_damage(fb_helper, x, y, width, height);
 692}
 693EXPORT_SYMBOL(drm_fb_helper_damage_area);
 694
 695/**
 696 * drm_fb_helper_deferred_io() - fbdev deferred_io callback function
 697 * @info: fb_info struct pointer
 698 * @pagereflist: list of mmap framebuffer pages that have to be flushed
 699 *
 700 * This function is used as the &fb_deferred_io.deferred_io
 701 * callback function for flushing the fbdev mmap writes.
 702 */
 703void drm_fb_helper_deferred_io(struct fb_info *info, struct list_head *pagereflist)
 704{
 705	struct drm_fb_helper *helper = info->par;
 706	unsigned long start, end, min_off, max_off, total_size;
 707	struct fb_deferred_io_pageref *pageref;
 708	struct drm_rect damage_area;
 709
 710	min_off = ULONG_MAX;
 711	max_off = 0;
 712	list_for_each_entry(pageref, pagereflist, list) {
 713		start = pageref->offset;
 714		end = start + PAGE_SIZE;
 715		min_off = min(min_off, start);
 716		max_off = max(max_off, end);
 717	}
 718
 719	/*
 720	 * As we can only track pages, we might reach beyond the end
 721	 * of the screen and account for non-existing scanlines. Hence,
 722	 * keep the covered memory area within the screen buffer.
 723	 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 724	if (info->screen_size)
 725		total_size = info->screen_size;
 726	else
 727		total_size = info->fix.smem_len;
 728	max_off = min(max_off, total_size);
 729
 730	if (min_off < max_off) {
 731		drm_fb_helper_memory_range_to_clip(info, min_off, max_off - min_off, &damage_area);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 732		drm_fb_helper_damage(helper, damage_area.x1, damage_area.y1,
 733				     drm_rect_width(&damage_area),
 734				     drm_rect_height(&damage_area));
 735	}
 
 
 736}
 737EXPORT_SYMBOL(drm_fb_helper_deferred_io);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 738
 739/**
 740 * drm_fb_helper_set_suspend - wrapper around fb_set_suspend
 741 * @fb_helper: driver-allocated fbdev helper, can be NULL
 742 * @suspend: whether to suspend or resume
 743 *
 744 * A wrapper around fb_set_suspend implemented by fbdev core.
 745 * Use drm_fb_helper_set_suspend_unlocked() if you don't need to take
 746 * the lock yourself
 747 */
 748void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper, bool suspend)
 749{
 750	if (fb_helper && fb_helper->info)
 751		fb_set_suspend(fb_helper->info, suspend);
 752}
 753EXPORT_SYMBOL(drm_fb_helper_set_suspend);
 754
 755/**
 756 * drm_fb_helper_set_suspend_unlocked - wrapper around fb_set_suspend that also
 757 *                                      takes the console lock
 758 * @fb_helper: driver-allocated fbdev helper, can be NULL
 759 * @suspend: whether to suspend or resume
 760 *
 761 * A wrapper around fb_set_suspend() that takes the console lock. If the lock
 762 * isn't available on resume, a worker is tasked with waiting for the lock
 763 * to become available. The console lock can be pretty contented on resume
 764 * due to all the printk activity.
 765 *
 766 * This function can be called multiple times with the same state since
 767 * &fb_info.state is checked to see if fbdev is running or not before locking.
 768 *
 769 * Use drm_fb_helper_set_suspend() if you need to take the lock yourself.
 770 */
 771void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper,
 772					bool suspend)
 773{
 774	if (!fb_helper || !fb_helper->info)
 775		return;
 776
 777	/* make sure there's no pending/ongoing resume */
 778	flush_work(&fb_helper->resume_work);
 779
 780	if (suspend) {
 781		if (fb_helper->info->state != FBINFO_STATE_RUNNING)
 782			return;
 783
 784		console_lock();
 785
 786	} else {
 787		if (fb_helper->info->state == FBINFO_STATE_RUNNING)
 788			return;
 789
 790		if (!console_trylock()) {
 791			schedule_work(&fb_helper->resume_work);
 792			return;
 793		}
 794	}
 795
 796	fb_set_suspend(fb_helper->info, suspend);
 797	console_unlock();
 798}
 799EXPORT_SYMBOL(drm_fb_helper_set_suspend_unlocked);
 800
 801static int setcmap_pseudo_palette(struct fb_cmap *cmap, struct fb_info *info)
 802{
 803	u32 *palette = (u32 *)info->pseudo_palette;
 804	int i;
 805
 806	if (cmap->start + cmap->len > 16)
 807		return -EINVAL;
 808
 809	for (i = 0; i < cmap->len; ++i) {
 810		u16 red = cmap->red[i];
 811		u16 green = cmap->green[i];
 812		u16 blue = cmap->blue[i];
 813		u32 value;
 814
 815		red >>= 16 - info->var.red.length;
 816		green >>= 16 - info->var.green.length;
 817		blue >>= 16 - info->var.blue.length;
 818		value = (red << info->var.red.offset) |
 819			(green << info->var.green.offset) |
 820			(blue << info->var.blue.offset);
 821		if (info->var.transp.length > 0) {
 822			u32 mask = (1 << info->var.transp.length) - 1;
 823
 824			mask <<= info->var.transp.offset;
 825			value |= mask;
 826		}
 827		palette[cmap->start + i] = value;
 828	}
 829
 830	return 0;
 831}
 832
 833static int setcmap_legacy(struct fb_cmap *cmap, struct fb_info *info)
 834{
 835	struct drm_fb_helper *fb_helper = info->par;
 836	struct drm_mode_set *modeset;
 837	struct drm_crtc *crtc;
 838	u16 *r, *g, *b;
 839	int ret = 0;
 840
 841	drm_modeset_lock_all(fb_helper->dev);
 842	drm_client_for_each_modeset(modeset, &fb_helper->client) {
 843		crtc = modeset->crtc;
 844		if (!crtc->funcs->gamma_set || !crtc->gamma_size) {
 845			ret = -EINVAL;
 846			goto out;
 847		}
 848
 849		if (cmap->start + cmap->len > crtc->gamma_size) {
 850			ret = -EINVAL;
 851			goto out;
 852		}
 853
 854		r = crtc->gamma_store;
 855		g = r + crtc->gamma_size;
 856		b = g + crtc->gamma_size;
 857
 858		memcpy(r + cmap->start, cmap->red, cmap->len * sizeof(*r));
 859		memcpy(g + cmap->start, cmap->green, cmap->len * sizeof(*g));
 860		memcpy(b + cmap->start, cmap->blue, cmap->len * sizeof(*b));
 861
 862		ret = crtc->funcs->gamma_set(crtc, r, g, b,
 863					     crtc->gamma_size, NULL);
 864		if (ret)
 865			goto out;
 866	}
 867out:
 868	drm_modeset_unlock_all(fb_helper->dev);
 869
 870	return ret;
 871}
 872
 873static struct drm_property_blob *setcmap_new_gamma_lut(struct drm_crtc *crtc,
 874						       struct fb_cmap *cmap)
 875{
 876	struct drm_device *dev = crtc->dev;
 877	struct drm_property_blob *gamma_lut;
 878	struct drm_color_lut *lut;
 879	int size = crtc->gamma_size;
 880	int i;
 881
 882	if (!size || cmap->start + cmap->len > size)
 883		return ERR_PTR(-EINVAL);
 884
 885	gamma_lut = drm_property_create_blob(dev, sizeof(*lut) * size, NULL);
 886	if (IS_ERR(gamma_lut))
 887		return gamma_lut;
 888
 889	lut = gamma_lut->data;
 890	if (cmap->start || cmap->len != size) {
 891		u16 *r = crtc->gamma_store;
 892		u16 *g = r + crtc->gamma_size;
 893		u16 *b = g + crtc->gamma_size;
 894
 895		for (i = 0; i < cmap->start; i++) {
 896			lut[i].red = r[i];
 897			lut[i].green = g[i];
 898			lut[i].blue = b[i];
 899		}
 900		for (i = cmap->start + cmap->len; i < size; i++) {
 901			lut[i].red = r[i];
 902			lut[i].green = g[i];
 903			lut[i].blue = b[i];
 904		}
 905	}
 906
 907	for (i = 0; i < cmap->len; i++) {
 908		lut[cmap->start + i].red = cmap->red[i];
 909		lut[cmap->start + i].green = cmap->green[i];
 910		lut[cmap->start + i].blue = cmap->blue[i];
 911	}
 912
 913	return gamma_lut;
 914}
 915
 916static int setcmap_atomic(struct fb_cmap *cmap, struct fb_info *info)
 917{
 918	struct drm_fb_helper *fb_helper = info->par;
 919	struct drm_device *dev = fb_helper->dev;
 920	struct drm_property_blob *gamma_lut = NULL;
 921	struct drm_modeset_acquire_ctx ctx;
 922	struct drm_crtc_state *crtc_state;
 923	struct drm_atomic_state *state;
 924	struct drm_mode_set *modeset;
 925	struct drm_crtc *crtc;
 926	u16 *r, *g, *b;
 927	bool replaced;
 928	int ret = 0;
 929
 930	drm_modeset_acquire_init(&ctx, 0);
 931
 932	state = drm_atomic_state_alloc(dev);
 933	if (!state) {
 934		ret = -ENOMEM;
 935		goto out_ctx;
 936	}
 937
 938	state->acquire_ctx = &ctx;
 939retry:
 940	drm_client_for_each_modeset(modeset, &fb_helper->client) {
 941		crtc = modeset->crtc;
 942
 943		if (!gamma_lut)
 944			gamma_lut = setcmap_new_gamma_lut(crtc, cmap);
 945		if (IS_ERR(gamma_lut)) {
 946			ret = PTR_ERR(gamma_lut);
 947			gamma_lut = NULL;
 948			goto out_state;
 949		}
 950
 951		crtc_state = drm_atomic_get_crtc_state(state, crtc);
 952		if (IS_ERR(crtc_state)) {
 953			ret = PTR_ERR(crtc_state);
 954			goto out_state;
 955		}
 956
 957		/*
 958		 * FIXME: This always uses gamma_lut. Some HW have only
 959		 * degamma_lut, in which case we should reset gamma_lut and set
 960		 * degamma_lut. See drm_crtc_legacy_gamma_set().
 961		 */
 962		replaced  = drm_property_replace_blob(&crtc_state->degamma_lut,
 963						      NULL);
 964		replaced |= drm_property_replace_blob(&crtc_state->ctm, NULL);
 965		replaced |= drm_property_replace_blob(&crtc_state->gamma_lut,
 966						      gamma_lut);
 967		crtc_state->color_mgmt_changed |= replaced;
 968	}
 969
 970	ret = drm_atomic_commit(state);
 971	if (ret)
 972		goto out_state;
 973
 974	drm_client_for_each_modeset(modeset, &fb_helper->client) {
 975		crtc = modeset->crtc;
 976
 977		r = crtc->gamma_store;
 978		g = r + crtc->gamma_size;
 979		b = g + crtc->gamma_size;
 980
 981		memcpy(r + cmap->start, cmap->red, cmap->len * sizeof(*r));
 982		memcpy(g + cmap->start, cmap->green, cmap->len * sizeof(*g));
 983		memcpy(b + cmap->start, cmap->blue, cmap->len * sizeof(*b));
 984	}
 985
 986out_state:
 987	if (ret == -EDEADLK)
 988		goto backoff;
 989
 990	drm_property_blob_put(gamma_lut);
 991	drm_atomic_state_put(state);
 992out_ctx:
 993	drm_modeset_drop_locks(&ctx);
 994	drm_modeset_acquire_fini(&ctx);
 995
 996	return ret;
 997
 998backoff:
 999	drm_atomic_state_clear(state);
1000	drm_modeset_backoff(&ctx);
1001	goto retry;
1002}
1003
1004/**
1005 * drm_fb_helper_setcmap - implementation for &fb_ops.fb_setcmap
1006 * @cmap: cmap to set
1007 * @info: fbdev registered by the helper
1008 */
1009int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info)
1010{
1011	struct drm_fb_helper *fb_helper = info->par;
1012	struct drm_device *dev = fb_helper->dev;
1013	int ret;
1014
1015	if (oops_in_progress)
1016		return -EBUSY;
1017
1018	mutex_lock(&fb_helper->lock);
1019
1020	if (!drm_master_internal_acquire(dev)) {
1021		ret = -EBUSY;
1022		goto unlock;
1023	}
1024
1025	mutex_lock(&fb_helper->client.modeset_mutex);
1026	if (info->fix.visual == FB_VISUAL_TRUECOLOR)
1027		ret = setcmap_pseudo_palette(cmap, info);
1028	else if (drm_drv_uses_atomic_modeset(fb_helper->dev))
1029		ret = setcmap_atomic(cmap, info);
1030	else
1031		ret = setcmap_legacy(cmap, info);
1032	mutex_unlock(&fb_helper->client.modeset_mutex);
1033
1034	drm_master_internal_release(dev);
1035unlock:
1036	mutex_unlock(&fb_helper->lock);
1037
1038	return ret;
1039}
1040EXPORT_SYMBOL(drm_fb_helper_setcmap);
1041
1042/**
1043 * drm_fb_helper_ioctl - legacy ioctl implementation
1044 * @info: fbdev registered by the helper
1045 * @cmd: ioctl command
1046 * @arg: ioctl argument
1047 *
1048 * A helper to implement the standard fbdev ioctl. Only
1049 * FBIO_WAITFORVSYNC is implemented for now.
1050 */
1051int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd,
1052			unsigned long arg)
1053{
1054	struct drm_fb_helper *fb_helper = info->par;
1055	struct drm_device *dev = fb_helper->dev;
1056	struct drm_crtc *crtc;
1057	int ret = 0;
1058
1059	mutex_lock(&fb_helper->lock);
1060	if (!drm_master_internal_acquire(dev)) {
1061		ret = -EBUSY;
1062		goto unlock;
1063	}
1064
1065	switch (cmd) {
1066	case FBIO_WAITFORVSYNC:
1067		/*
1068		 * Only consider the first CRTC.
1069		 *
1070		 * This ioctl is supposed to take the CRTC number as
1071		 * an argument, but in fbdev times, what that number
1072		 * was supposed to be was quite unclear, different
1073		 * drivers were passing that argument differently
1074		 * (some by reference, some by value), and most of the
1075		 * userspace applications were just hardcoding 0 as an
1076		 * argument.
1077		 *
1078		 * The first CRTC should be the integrated panel on
1079		 * most drivers, so this is the best choice we can
1080		 * make. If we're not smart enough here, one should
1081		 * just consider switch the userspace to KMS.
1082		 */
1083		crtc = fb_helper->client.modesets[0].crtc;
1084
1085		/*
1086		 * Only wait for a vblank event if the CRTC is
1087		 * enabled, otherwise just don't do anythintg,
1088		 * not even report an error.
1089		 */
1090		ret = drm_crtc_vblank_get(crtc);
1091		if (!ret) {
1092			drm_crtc_wait_one_vblank(crtc);
1093			drm_crtc_vblank_put(crtc);
1094		}
1095
1096		ret = 0;
1097		break;
1098	default:
1099		ret = -ENOTTY;
1100	}
1101
1102	drm_master_internal_release(dev);
1103unlock:
1104	mutex_unlock(&fb_helper->lock);
1105	return ret;
1106}
1107EXPORT_SYMBOL(drm_fb_helper_ioctl);
1108
1109static bool drm_fb_pixel_format_equal(const struct fb_var_screeninfo *var_1,
1110				      const struct fb_var_screeninfo *var_2)
1111{
1112	return var_1->bits_per_pixel == var_2->bits_per_pixel &&
1113	       var_1->grayscale == var_2->grayscale &&
1114	       var_1->red.offset == var_2->red.offset &&
1115	       var_1->red.length == var_2->red.length &&
1116	       var_1->red.msb_right == var_2->red.msb_right &&
1117	       var_1->green.offset == var_2->green.offset &&
1118	       var_1->green.length == var_2->green.length &&
1119	       var_1->green.msb_right == var_2->green.msb_right &&
1120	       var_1->blue.offset == var_2->blue.offset &&
1121	       var_1->blue.length == var_2->blue.length &&
1122	       var_1->blue.msb_right == var_2->blue.msb_right &&
1123	       var_1->transp.offset == var_2->transp.offset &&
1124	       var_1->transp.length == var_2->transp.length &&
1125	       var_1->transp.msb_right == var_2->transp.msb_right;
1126}
1127
1128static void drm_fb_helper_fill_pixel_fmt(struct fb_var_screeninfo *var,
1129					 const struct drm_format_info *format)
1130{
1131	u8 depth = format->depth;
1132
1133	if (format->is_color_indexed) {
1134		var->red.offset = 0;
1135		var->green.offset = 0;
1136		var->blue.offset = 0;
1137		var->red.length = depth;
1138		var->green.length = depth;
1139		var->blue.length = depth;
1140		var->transp.offset = 0;
1141		var->transp.length = 0;
1142		return;
1143	}
1144
1145	switch (depth) {
1146	case 15:
1147		var->red.offset = 10;
1148		var->green.offset = 5;
1149		var->blue.offset = 0;
1150		var->red.length = 5;
1151		var->green.length = 5;
1152		var->blue.length = 5;
1153		var->transp.offset = 15;
1154		var->transp.length = 1;
1155		break;
1156	case 16:
1157		var->red.offset = 11;
1158		var->green.offset = 5;
1159		var->blue.offset = 0;
1160		var->red.length = 5;
1161		var->green.length = 6;
1162		var->blue.length = 5;
1163		var->transp.offset = 0;
1164		break;
1165	case 24:
1166		var->red.offset = 16;
1167		var->green.offset = 8;
1168		var->blue.offset = 0;
1169		var->red.length = 8;
1170		var->green.length = 8;
1171		var->blue.length = 8;
1172		var->transp.offset = 0;
1173		var->transp.length = 0;
1174		break;
1175	case 32:
1176		var->red.offset = 16;
1177		var->green.offset = 8;
1178		var->blue.offset = 0;
1179		var->red.length = 8;
1180		var->green.length = 8;
1181		var->blue.length = 8;
1182		var->transp.offset = 24;
1183		var->transp.length = 8;
1184		break;
1185	default:
1186		break;
1187	}
1188}
1189
1190static void __fill_var(struct fb_var_screeninfo *var, struct fb_info *info,
1191		       struct drm_framebuffer *fb)
1192{
1193	int i;
1194
1195	var->xres_virtual = fb->width;
1196	var->yres_virtual = fb->height;
1197	var->accel_flags = 0;
1198	var->bits_per_pixel = drm_format_info_bpp(fb->format, 0);
1199
1200	var->height = info->var.height;
1201	var->width = info->var.width;
1202
1203	var->left_margin = var->right_margin = 0;
1204	var->upper_margin = var->lower_margin = 0;
1205	var->hsync_len = var->vsync_len = 0;
1206	var->sync = var->vmode = 0;
1207	var->rotate = 0;
1208	var->colorspace = 0;
1209	for (i = 0; i < 4; i++)
1210		var->reserved[i] = 0;
1211}
1212
1213/**
1214 * drm_fb_helper_check_var - implementation for &fb_ops.fb_check_var
1215 * @var: screeninfo to check
1216 * @info: fbdev registered by the helper
1217 */
1218int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
1219			    struct fb_info *info)
1220{
1221	struct drm_fb_helper *fb_helper = info->par;
1222	struct drm_framebuffer *fb = fb_helper->fb;
1223	const struct drm_format_info *format = fb->format;
1224	struct drm_device *dev = fb_helper->dev;
1225	unsigned int bpp;
1226
1227	if (in_dbg_master())
1228		return -EINVAL;
1229
1230	if (var->pixclock != 0) {
1231		drm_dbg_kms(dev, "fbdev emulation doesn't support changing the pixel clock, value of pixclock is ignored\n");
1232		var->pixclock = 0;
1233	}
1234
1235	switch (format->format) {
1236	case DRM_FORMAT_C1:
1237	case DRM_FORMAT_C2:
1238	case DRM_FORMAT_C4:
1239		/* supported format with sub-byte pixels */
1240		break;
1241
1242	default:
1243		if ((drm_format_info_block_width(format, 0) > 1) ||
1244		    (drm_format_info_block_height(format, 0) > 1))
1245			return -EINVAL;
1246		break;
1247	}
1248
1249	/*
1250	 * Changes struct fb_var_screeninfo are currently not pushed back
1251	 * to KMS, hence fail if different settings are requested.
1252	 */
1253	bpp = drm_format_info_bpp(format, 0);
1254	if (var->bits_per_pixel > bpp ||
1255	    var->xres > fb->width || var->yres > fb->height ||
1256	    var->xres_virtual > fb->width || var->yres_virtual > fb->height) {
1257		drm_dbg_kms(dev, "fb requested width/height/bpp can't fit in current fb "
1258			  "request %dx%d-%d (virtual %dx%d) > %dx%d-%d\n",
1259			  var->xres, var->yres, var->bits_per_pixel,
1260			  var->xres_virtual, var->yres_virtual,
1261			  fb->width, fb->height, bpp);
1262		return -EINVAL;
1263	}
1264
1265	__fill_var(var, info, fb);
1266
1267	/*
1268	 * fb_pan_display() validates this, but fb_set_par() doesn't and just
1269	 * falls over. Note that __fill_var above adjusts y/res_virtual.
1270	 */
1271	if (var->yoffset > var->yres_virtual - var->yres ||
1272	    var->xoffset > var->xres_virtual - var->xres)
1273		return -EINVAL;
1274
1275	/* We neither support grayscale nor FOURCC (also stored in here). */
1276	if (var->grayscale > 0)
1277		return -EINVAL;
1278
1279	if (var->nonstd)
1280		return -EINVAL;
1281
1282	/*
1283	 * Workaround for SDL 1.2, which is known to be setting all pixel format
1284	 * fields values to zero in some cases. We treat this situation as a
1285	 * kind of "use some reasonable autodetected values".
1286	 */
1287	if (!var->red.offset     && !var->green.offset    &&
1288	    !var->blue.offset    && !var->transp.offset   &&
1289	    !var->red.length     && !var->green.length    &&
1290	    !var->blue.length    && !var->transp.length   &&
1291	    !var->red.msb_right  && !var->green.msb_right &&
1292	    !var->blue.msb_right && !var->transp.msb_right) {
1293		drm_fb_helper_fill_pixel_fmt(var, format);
1294	}
1295
1296	/*
 
 
 
 
 
1297	 * drm fbdev emulation doesn't support changing the pixel format at all,
1298	 * so reject all pixel format changing requests.
1299	 */
1300	if (!drm_fb_pixel_format_equal(var, &info->var)) {
1301		drm_dbg_kms(dev, "fbdev emulation doesn't support changing the pixel format\n");
1302		return -EINVAL;
1303	}
1304
1305	return 0;
1306}
1307EXPORT_SYMBOL(drm_fb_helper_check_var);
1308
1309/**
1310 * drm_fb_helper_set_par - implementation for &fb_ops.fb_set_par
1311 * @info: fbdev registered by the helper
1312 *
1313 * This will let fbcon do the mode init and is called at initialization time by
1314 * the fbdev core when registering the driver, and later on through the hotplug
1315 * callback.
1316 */
1317int drm_fb_helper_set_par(struct fb_info *info)
1318{
1319	struct drm_fb_helper *fb_helper = info->par;
1320	struct fb_var_screeninfo *var = &info->var;
1321	bool force;
1322
1323	if (oops_in_progress)
1324		return -EBUSY;
1325
 
 
 
 
 
1326	/*
1327	 * Normally we want to make sure that a kms master takes precedence over
1328	 * fbdev, to avoid fbdev flickering and occasionally stealing the
1329	 * display status. But Xorg first sets the vt back to text mode using
1330	 * the KDSET IOCTL with KD_TEXT, and only after that drops the master
1331	 * status when exiting.
1332	 *
1333	 * In the past this was caught by drm_fb_helper_lastclose(), but on
1334	 * modern systems where logind always keeps a drm fd open to orchestrate
1335	 * the vt switching, this doesn't work.
1336	 *
1337	 * To not break the userspace ABI we have this special case here, which
1338	 * is only used for the above case. Everything else uses the normal
1339	 * commit function, which ensures that we never steal the display from
1340	 * an active drm master.
1341	 */
1342	force = var->activate & FB_ACTIVATE_KD_TEXT;
1343
1344	__drm_fb_helper_restore_fbdev_mode_unlocked(fb_helper, force);
1345
1346	return 0;
1347}
1348EXPORT_SYMBOL(drm_fb_helper_set_par);
1349
1350static void pan_set(struct drm_fb_helper *fb_helper, int x, int y)
1351{
1352	struct drm_mode_set *mode_set;
1353
1354	mutex_lock(&fb_helper->client.modeset_mutex);
1355	drm_client_for_each_modeset(mode_set, &fb_helper->client) {
1356		mode_set->x = x;
1357		mode_set->y = y;
1358	}
1359	mutex_unlock(&fb_helper->client.modeset_mutex);
1360}
1361
1362static int pan_display_atomic(struct fb_var_screeninfo *var,
1363			      struct fb_info *info)
1364{
1365	struct drm_fb_helper *fb_helper = info->par;
1366	int ret;
1367
1368	pan_set(fb_helper, var->xoffset, var->yoffset);
1369
1370	ret = drm_client_modeset_commit_locked(&fb_helper->client);
1371	if (!ret) {
1372		info->var.xoffset = var->xoffset;
1373		info->var.yoffset = var->yoffset;
1374	} else
1375		pan_set(fb_helper, info->var.xoffset, info->var.yoffset);
1376
1377	return ret;
1378}
1379
1380static int pan_display_legacy(struct fb_var_screeninfo *var,
1381			      struct fb_info *info)
1382{
1383	struct drm_fb_helper *fb_helper = info->par;
1384	struct drm_client_dev *client = &fb_helper->client;
1385	struct drm_mode_set *modeset;
1386	int ret = 0;
1387
1388	mutex_lock(&client->modeset_mutex);
1389	drm_modeset_lock_all(fb_helper->dev);
1390	drm_client_for_each_modeset(modeset, client) {
1391		modeset->x = var->xoffset;
1392		modeset->y = var->yoffset;
1393
1394		if (modeset->num_connectors) {
1395			ret = drm_mode_set_config_internal(modeset);
1396			if (!ret) {
1397				info->var.xoffset = var->xoffset;
1398				info->var.yoffset = var->yoffset;
1399			}
1400		}
1401	}
1402	drm_modeset_unlock_all(fb_helper->dev);
1403	mutex_unlock(&client->modeset_mutex);
1404
1405	return ret;
1406}
1407
1408/**
1409 * drm_fb_helper_pan_display - implementation for &fb_ops.fb_pan_display
1410 * @var: updated screen information
1411 * @info: fbdev registered by the helper
1412 */
1413int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
1414			      struct fb_info *info)
1415{
1416	struct drm_fb_helper *fb_helper = info->par;
1417	struct drm_device *dev = fb_helper->dev;
1418	int ret;
1419
1420	if (oops_in_progress)
1421		return -EBUSY;
1422
1423	mutex_lock(&fb_helper->lock);
1424	if (!drm_master_internal_acquire(dev)) {
1425		ret = -EBUSY;
1426		goto unlock;
1427	}
1428
1429	if (drm_drv_uses_atomic_modeset(dev))
1430		ret = pan_display_atomic(var, info);
1431	else
1432		ret = pan_display_legacy(var, info);
1433
1434	drm_master_internal_release(dev);
1435unlock:
1436	mutex_unlock(&fb_helper->lock);
1437
1438	return ret;
1439}
1440EXPORT_SYMBOL(drm_fb_helper_pan_display);
1441
1442static uint32_t drm_fb_helper_find_format(struct drm_fb_helper *fb_helper, const uint32_t *formats,
1443					  size_t format_count, uint32_t bpp, uint32_t depth)
 
 
 
 
1444{
 
1445	struct drm_device *dev = fb_helper->dev;
1446	uint32_t format;
1447	size_t i;
 
 
 
 
 
 
 
 
 
 
 
 
1448
1449	/*
1450	 * Do not consider YUV or other complicated formats
1451	 * for framebuffers. This means only legacy formats
1452	 * are supported (fmt->depth is a legacy field), but
1453	 * the framebuffer emulation can only deal with such
1454	 * formats, specifically RGB/BGA formats.
1455	 */
1456	format = drm_mode_legacy_fb_format(bpp, depth);
1457	if (!format)
1458		goto err;
1459
1460	for (i = 0; i < format_count; ++i) {
1461		if (formats[i] == format)
1462			return format;
1463	}
1464
1465err:
1466	/* We found nothing. */
1467	drm_warn(dev, "bpp/depth value of %u/%u not supported\n", bpp, depth);
1468
1469	return DRM_FORMAT_INVALID;
1470}
1471
1472static uint32_t drm_fb_helper_find_color_mode_format(struct drm_fb_helper *fb_helper,
1473						     const uint32_t *formats, size_t format_count,
1474						     unsigned int color_mode)
1475{
1476	struct drm_device *dev = fb_helper->dev;
1477	uint32_t bpp, depth;
1478
1479	switch (color_mode) {
1480	case 1:
1481	case 2:
1482	case 4:
1483	case 8:
1484	case 16:
1485	case 24:
1486		bpp = depth = color_mode;
1487		break;
1488	case 15:
1489		bpp = 16;
1490		depth = 15;
1491		break;
1492	case 32:
1493		bpp = 32;
1494		depth = 24;
1495		break;
1496	default:
1497		drm_info(dev, "unsupported color mode of %d\n", color_mode);
1498		return DRM_FORMAT_INVALID;
 
 
1499	}
 
1500
1501	return drm_fb_helper_find_format(fb_helper, formats, format_count, bpp, depth);
1502}
1503
1504static int __drm_fb_helper_find_sizes(struct drm_fb_helper *fb_helper,
1505				      struct drm_fb_helper_surface_size *sizes)
1506{
1507	struct drm_client_dev *client = &fb_helper->client;
1508	struct drm_device *dev = fb_helper->dev;
1509	int crtc_count = 0;
1510	struct drm_connector_list_iter conn_iter;
1511	struct drm_connector *connector;
1512	struct drm_mode_set *mode_set;
1513	uint32_t surface_format = DRM_FORMAT_INVALID;
1514	const struct drm_format_info *info;
1515
1516	memset(sizes, 0, sizeof(*sizes));
1517	sizes->fb_width = (u32)-1;
1518	sizes->fb_height = (u32)-1;
1519
1520	drm_client_for_each_modeset(mode_set, client) {
1521		struct drm_crtc *crtc = mode_set->crtc;
1522		struct drm_plane *plane = crtc->primary;
 
1523
1524		drm_dbg_kms(dev, "test CRTC %u primary plane\n", drm_crtc_index(crtc));
1525
1526		drm_connector_list_iter_begin(fb_helper->dev, &conn_iter);
1527		drm_client_for_each_connector_iter(connector, &conn_iter) {
1528			struct drm_cmdline_mode *cmdline_mode = &connector->cmdline_mode;
1529
1530			if (!cmdline_mode->bpp_specified)
 
 
 
 
 
 
 
 
 
1531				continue;
1532
1533			surface_format = drm_fb_helper_find_color_mode_format(fb_helper,
1534									      plane->format_types,
1535									      plane->format_count,
1536									      cmdline_mode->bpp);
1537			if (surface_format != DRM_FORMAT_INVALID)
1538				break; /* found supported format */
1539		}
1540		drm_connector_list_iter_end(&conn_iter);
1541
1542		if (surface_format != DRM_FORMAT_INVALID)
1543			break; /* found supported format */
 
1544
1545		/* try preferred color mode */
1546		surface_format = drm_fb_helper_find_color_mode_format(fb_helper,
1547								      plane->format_types,
1548								      plane->format_count,
1549								      fb_helper->preferred_bpp);
1550		if (surface_format != DRM_FORMAT_INVALID)
1551			break; /* found supported format */
1552	}
1553
1554	if (surface_format == DRM_FORMAT_INVALID) {
1555		/*
1556		 * If none of the given color modes works, fall back
1557		 * to XRGB8888. Drivers are expected to provide this
1558		 * format for compatibility with legacy applications.
1559		 */
1560		drm_warn(dev, "No compatible format found\n");
1561		surface_format = drm_driver_legacy_fb_format(dev, 32, 24);
1562	}
1563
1564	info = drm_format_info(surface_format);
1565	sizes->surface_bpp = drm_format_info_bpp(info, 0);
1566	sizes->surface_depth = info->depth;
1567
1568	/* first up get a count of crtcs now in use and new min/maxes width/heights */
1569	crtc_count = 0;
1570	drm_client_for_each_modeset(mode_set, client) {
1571		struct drm_display_mode *desired_mode;
1572		int x, y, j;
1573		/* in case of tile group, are we the last tile vert or horiz?
1574		 * If no tile group you are always the last one both vertically
1575		 * and horizontally
1576		 */
1577		bool lastv = true, lasth = true;
1578
1579		desired_mode = mode_set->mode;
1580
1581		if (!desired_mode)
1582			continue;
1583
1584		crtc_count++;
1585
1586		x = mode_set->x;
1587		y = mode_set->y;
1588
1589		sizes->surface_width  =
1590			max_t(u32, desired_mode->hdisplay + x, sizes->surface_width);
1591		sizes->surface_height =
1592			max_t(u32, desired_mode->vdisplay + y, sizes->surface_height);
1593
1594		for (j = 0; j < mode_set->num_connectors; j++) {
1595			struct drm_connector *connector = mode_set->connectors[j];
1596
1597			if (connector->has_tile &&
1598			    desired_mode->hdisplay == connector->tile_h_size &&
1599			    desired_mode->vdisplay == connector->tile_v_size) {
1600				lasth = (connector->tile_h_loc == (connector->num_h_tile - 1));
1601				lastv = (connector->tile_v_loc == (connector->num_v_tile - 1));
1602				/* cloning to multiple tiles is just crazy-talk, so: */
1603				break;
1604			}
1605		}
1606
1607		if (lasth)
1608			sizes->fb_width  = min_t(u32, desired_mode->hdisplay + x, sizes->fb_width);
1609		if (lastv)
1610			sizes->fb_height = min_t(u32, desired_mode->vdisplay + y, sizes->fb_height);
1611	}
 
1612
1613	if (crtc_count == 0 || sizes->fb_width == -1 || sizes->fb_height == -1) {
1614		drm_info(dev, "Cannot find any crtc or sizes\n");
 
 
 
 
1615		return -EAGAIN;
1616	}
1617
1618	return 0;
1619}
1620
1621static int drm_fb_helper_find_sizes(struct drm_fb_helper *fb_helper,
1622				    struct drm_fb_helper_surface_size *sizes)
1623{
1624	struct drm_client_dev *client = &fb_helper->client;
1625	struct drm_device *dev = fb_helper->dev;
1626	struct drm_mode_config *config = &dev->mode_config;
1627	int ret;
1628
1629	mutex_lock(&client->modeset_mutex);
1630	ret = __drm_fb_helper_find_sizes(fb_helper, sizes);
1631	mutex_unlock(&client->modeset_mutex);
1632
1633	if (ret)
1634		return ret;
1635
1636	/* Handle our overallocation */
1637	sizes->surface_height *= drm_fbdev_overalloc;
1638	sizes->surface_height /= 100;
1639	if (sizes->surface_height > config->max_height) {
1640		drm_dbg_kms(dev, "Fbdev over-allocation too large; clamping height to %d\n",
1641			    config->max_height);
1642		sizes->surface_height = config->max_height;
1643	}
1644
1645	return 0;
1646}
1647
1648/*
1649 * Allocates the backing storage and sets up the fbdev info structure through
1650 * the ->fb_probe callback.
1651 */
1652static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper)
1653{
1654	struct drm_client_dev *client = &fb_helper->client;
1655	struct drm_device *dev = fb_helper->dev;
1656	struct drm_fb_helper_surface_size sizes;
1657	int ret;
1658
1659	ret = drm_fb_helper_find_sizes(fb_helper, &sizes);
1660	if (ret) {
1661		/* First time: disable all crtc's.. */
1662		if (!fb_helper->deferred_setup)
1663			drm_client_modeset_commit(client);
1664		return ret;
1665	}
1666
1667	/* push down into drivers */
1668	ret = (*fb_helper->funcs->fb_probe)(fb_helper, &sizes);
1669	if (ret < 0)
1670		return ret;
1671
1672	strcpy(fb_helper->fb->comm, "[fbcon]");
1673
1674	/* Set the fb info for vgaswitcheroo clients. Does nothing otherwise. */
1675	if (dev_is_pci(dev->dev))
1676		vga_switcheroo_client_fb_set(to_pci_dev(dev->dev), fb_helper->info);
1677
1678	return 0;
1679}
1680
1681static void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
1682				   bool is_color_indexed)
1683{
1684	info->fix.type = FB_TYPE_PACKED_PIXELS;
1685	info->fix.visual = is_color_indexed ? FB_VISUAL_PSEUDOCOLOR
1686					    : FB_VISUAL_TRUECOLOR;
1687	info->fix.mmio_start = 0;
1688	info->fix.mmio_len = 0;
1689	info->fix.type_aux = 0;
1690	info->fix.xpanstep = 1; /* doing it in hw */
1691	info->fix.ypanstep = 1; /* doing it in hw */
1692	info->fix.ywrapstep = 0;
1693	info->fix.accel = FB_ACCEL_NONE;
1694
1695	info->fix.line_length = pitch;
1696}
1697
1698static void drm_fb_helper_fill_var(struct fb_info *info,
1699				   struct drm_fb_helper *fb_helper,
1700				   uint32_t fb_width, uint32_t fb_height)
1701{
1702	struct drm_framebuffer *fb = fb_helper->fb;
1703	const struct drm_format_info *format = fb->format;
1704
1705	switch (format->format) {
1706	case DRM_FORMAT_C1:
1707	case DRM_FORMAT_C2:
1708	case DRM_FORMAT_C4:
1709		/* supported format with sub-byte pixels */
1710		break;
1711
1712	default:
1713		WARN_ON((drm_format_info_block_width(format, 0) > 1) ||
1714			(drm_format_info_block_height(format, 0) > 1));
1715		break;
1716	}
1717
1718	info->pseudo_palette = fb_helper->pseudo_palette;
 
 
 
 
1719	info->var.xoffset = 0;
1720	info->var.yoffset = 0;
1721	__fill_var(&info->var, info, fb);
1722	info->var.activate = FB_ACTIVATE_NOW;
1723
1724	drm_fb_helper_fill_pixel_fmt(&info->var, format);
1725
1726	info->var.xres = fb_width;
1727	info->var.yres = fb_height;
1728}
1729
1730/**
1731 * drm_fb_helper_fill_info - initializes fbdev information
1732 * @info: fbdev instance to set up
1733 * @fb_helper: fb helper instance to use as template
1734 * @sizes: describes fbdev size and scanout surface size
1735 *
1736 * Sets up the variable and fixed fbdev metainformation from the given fb helper
1737 * instance and the drm framebuffer allocated in &drm_fb_helper.fb.
1738 *
1739 * Drivers should call this (or their equivalent setup code) from their
1740 * &drm_fb_helper_funcs.fb_probe callback after having allocated the fbdev
1741 * backing storage framebuffer.
1742 */
1743void drm_fb_helper_fill_info(struct fb_info *info,
1744			     struct drm_fb_helper *fb_helper,
1745			     struct drm_fb_helper_surface_size *sizes)
1746{
1747	struct drm_framebuffer *fb = fb_helper->fb;
1748
1749	drm_fb_helper_fill_fix(info, fb->pitches[0],
1750			       fb->format->is_color_indexed);
1751	drm_fb_helper_fill_var(info, fb_helper,
1752			       sizes->fb_width, sizes->fb_height);
1753
1754	info->par = fb_helper;
1755	/*
1756	 * The DRM drivers fbdev emulation device name can be confusing if the
1757	 * driver name also has a "drm" suffix on it. Leading to names such as
1758	 * "simpledrmdrmfb" in /proc/fb. Unfortunately, it's an uAPI and can't
1759	 * be changed due user-space tools (e.g: pm-utils) matching against it.
1760	 */
1761	snprintf(info->fix.id, sizeof(info->fix.id), "%sdrmfb",
1762		 fb_helper->dev->driver->name);
1763
1764}
1765EXPORT_SYMBOL(drm_fb_helper_fill_info);
1766
1767/*
1768 * This is a continuation of drm_setup_crtcs() that sets up anything related
1769 * to the framebuffer. During initialization, drm_setup_crtcs() is called before
1770 * the framebuffer has been allocated (fb_helper->fb and fb_helper->info).
1771 * So, any setup that touches those fields needs to be done here instead of in
1772 * drm_setup_crtcs().
1773 */
1774static void drm_setup_crtcs_fb(struct drm_fb_helper *fb_helper)
1775{
1776	struct drm_client_dev *client = &fb_helper->client;
1777	struct drm_connector_list_iter conn_iter;
1778	struct fb_info *info = fb_helper->info;
1779	unsigned int rotation, sw_rotations = 0;
1780	struct drm_connector *connector;
1781	struct drm_mode_set *modeset;
1782
1783	mutex_lock(&client->modeset_mutex);
1784	drm_client_for_each_modeset(modeset, client) {
1785		if (!modeset->num_connectors)
1786			continue;
1787
1788		modeset->fb = fb_helper->fb;
1789
1790		if (drm_client_rotation(modeset, &rotation))
1791			/* Rotating in hardware, fbcon should not rotate */
1792			sw_rotations |= DRM_MODE_ROTATE_0;
1793		else
1794			sw_rotations |= rotation;
1795	}
1796	mutex_unlock(&client->modeset_mutex);
1797
1798	drm_connector_list_iter_begin(fb_helper->dev, &conn_iter);
1799	drm_client_for_each_connector_iter(connector, &conn_iter) {
1800
1801		/* use first connected connector for the physical dimensions */
1802		if (connector->status == connector_status_connected) {
1803			info->var.width = connector->display_info.width_mm;
1804			info->var.height = connector->display_info.height_mm;
1805			break;
1806		}
1807	}
1808	drm_connector_list_iter_end(&conn_iter);
1809
1810	switch (sw_rotations) {
1811	case DRM_MODE_ROTATE_0:
1812		info->fbcon_rotate_hint = FB_ROTATE_UR;
1813		break;
1814	case DRM_MODE_ROTATE_90:
1815		info->fbcon_rotate_hint = FB_ROTATE_CCW;
1816		break;
1817	case DRM_MODE_ROTATE_180:
1818		info->fbcon_rotate_hint = FB_ROTATE_UD;
1819		break;
1820	case DRM_MODE_ROTATE_270:
1821		info->fbcon_rotate_hint = FB_ROTATE_CW;
1822		break;
1823	default:
1824		/*
1825		 * Multiple bits are set / multiple rotations requested
1826		 * fbcon cannot handle separate rotation settings per
1827		 * output, so fallback to unrotated.
1828		 */
1829		info->fbcon_rotate_hint = FB_ROTATE_UR;
1830	}
1831}
1832
1833/* Note: Drops fb_helper->lock before returning. */
1834static int
1835__drm_fb_helper_initial_config_and_unlock(struct drm_fb_helper *fb_helper)
 
1836{
1837	struct drm_device *dev = fb_helper->dev;
1838	struct fb_info *info;
1839	unsigned int width, height;
1840	int ret;
1841
1842	width = dev->mode_config.max_width;
1843	height = dev->mode_config.max_height;
1844
1845	drm_client_modeset_probe(&fb_helper->client, width, height);
1846	ret = drm_fb_helper_single_fb_probe(fb_helper);
1847	if (ret < 0) {
1848		if (ret == -EAGAIN) {
 
1849			fb_helper->deferred_setup = true;
1850			ret = 0;
1851		}
1852		mutex_unlock(&fb_helper->lock);
1853
1854		return ret;
1855	}
1856	drm_setup_crtcs_fb(fb_helper);
1857
1858	fb_helper->deferred_setup = false;
1859
1860	info = fb_helper->info;
1861	info->var.pixclock = 0;
1862
1863	if (!drm_leak_fbdev_smem)
 
 
 
1864		info->flags |= FBINFO_HIDE_SMEM_START;
1865
1866	/* Need to drop locks to avoid recursive deadlock in
1867	 * register_framebuffer. This is ok because the only thing left to do is
1868	 * register the fbdev emulation instance in kernel_fb_helper_list. */
1869	mutex_unlock(&fb_helper->lock);
1870
1871	ret = register_framebuffer(info);
1872	if (ret < 0)
1873		return ret;
1874
1875	drm_info(dev, "fb%d: %s frame buffer device\n",
1876		 info->node, info->fix.id);
1877
1878	mutex_lock(&kernel_fb_helper_lock);
1879	if (list_empty(&kernel_fb_helper_list))
1880		register_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
1881
1882	list_add(&fb_helper->kernel_fb_list, &kernel_fb_helper_list);
1883	mutex_unlock(&kernel_fb_helper_lock);
1884
1885	return 0;
1886}
1887
1888/**
1889 * drm_fb_helper_initial_config - setup a sane initial connector configuration
1890 * @fb_helper: fb_helper device struct
 
1891 *
1892 * Scans the CRTCs and connectors and tries to put together an initial setup.
1893 * At the moment, this is a cloned configuration across all heads with
1894 * a new framebuffer object as the backing store.
1895 *
1896 * Note that this also registers the fbdev and so allows userspace to call into
1897 * the driver through the fbdev interfaces.
1898 *
1899 * This function will call down into the &drm_fb_helper_funcs.fb_probe callback
1900 * to let the driver allocate and initialize the fbdev info structure and the
1901 * drm framebuffer used to back the fbdev. drm_fb_helper_fill_info() is provided
1902 * as a helper to setup simple default values for the fbdev info structure.
1903 *
1904 * HANG DEBUGGING:
1905 *
1906 * When you have fbcon support built-in or already loaded, this function will do
1907 * a full modeset to setup the fbdev console. Due to locking misdesign in the
1908 * VT/fbdev subsystem that entire modeset sequence has to be done while holding
1909 * console_lock. Until console_unlock is called no dmesg lines will be sent out
1910 * to consoles, not even serial console. This means when your driver crashes,
1911 * you will see absolutely nothing else but a system stuck in this function,
1912 * with no further output. Any kind of printk() you place within your own driver
1913 * or in the drm core modeset code will also never show up.
1914 *
1915 * Standard debug practice is to run the fbcon setup without taking the
1916 * console_lock as a hack, to be able to see backtraces and crashes on the
1917 * serial line. This can be done by setting the fb.lockless_register_fb=1 kernel
1918 * cmdline option.
1919 *
1920 * The other option is to just disable fbdev emulation since very likely the
1921 * first modeset from userspace will crash in the same way, and is even easier
1922 * to debug. This can be done by setting the drm_kms_helper.fbdev_emulation=0
1923 * kernel cmdline option.
1924 *
1925 * RETURNS:
1926 * Zero if everything went ok, nonzero otherwise.
1927 */
1928int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper)
1929{
1930	int ret;
1931
1932	if (!drm_fbdev_emulation)
1933		return 0;
1934
1935	mutex_lock(&fb_helper->lock);
1936	ret = __drm_fb_helper_initial_config_and_unlock(fb_helper);
1937
1938	return ret;
1939}
1940EXPORT_SYMBOL(drm_fb_helper_initial_config);
1941
1942/**
1943 * drm_fb_helper_hotplug_event - respond to a hotplug notification by
1944 *                               probing all the outputs attached to the fb
1945 * @fb_helper: driver-allocated fbdev helper, can be NULL
1946 *
1947 * Scan the connectors attached to the fb_helper and try to put together a
1948 * setup after notification of a change in output configuration.
1949 *
1950 * Called at runtime, takes the mode config locks to be able to check/change the
1951 * modeset configuration. Must be run from process context (which usually means
1952 * either the output polling work or a work item launched from the driver's
1953 * hotplug interrupt).
1954 *
1955 * Note that drivers may call this even before calling
1956 * drm_fb_helper_initial_config but only after drm_fb_helper_init. This allows
1957 * for a race-free fbcon setup and will make sure that the fbdev emulation will
1958 * not miss any hotplug events.
1959 *
1960 * RETURNS:
1961 * 0 on success and a non-zero error code otherwise.
1962 */
1963int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
1964{
1965	int err = 0;
1966
1967	if (!drm_fbdev_emulation || !fb_helper)
1968		return 0;
1969
1970	mutex_lock(&fb_helper->lock);
1971	if (fb_helper->deferred_setup) {
1972		err = __drm_fb_helper_initial_config_and_unlock(fb_helper);
 
1973		return err;
1974	}
1975
1976	if (!fb_helper->fb || !drm_master_internal_acquire(fb_helper->dev)) {
1977		fb_helper->delayed_hotplug = true;
1978		mutex_unlock(&fb_helper->lock);
1979		return err;
1980	}
1981
1982	drm_master_internal_release(fb_helper->dev);
1983
1984	drm_dbg_kms(fb_helper->dev, "\n");
1985
1986	drm_client_modeset_probe(&fb_helper->client, fb_helper->fb->width, fb_helper->fb->height);
1987	drm_setup_crtcs_fb(fb_helper);
1988	mutex_unlock(&fb_helper->lock);
1989
1990	drm_fb_helper_set_par(fb_helper->info);
1991
1992	return 0;
1993}
1994EXPORT_SYMBOL(drm_fb_helper_hotplug_event);
1995
1996/**
1997 * drm_fb_helper_lastclose - DRM driver lastclose helper for fbdev emulation
1998 * @dev: DRM device
1999 *
2000 * This function can be used as the &drm_driver->lastclose callback for drivers
2001 * that only need to call drm_fb_helper_restore_fbdev_mode_unlocked().
2002 */
2003void drm_fb_helper_lastclose(struct drm_device *dev)
2004{
2005	drm_fb_helper_restore_fbdev_mode_unlocked(dev->fb_helper);
2006}
2007EXPORT_SYMBOL(drm_fb_helper_lastclose);
2008
2009/**
2010 * drm_fb_helper_output_poll_changed - DRM mode config \.output_poll_changed
2011 *                                     helper for fbdev emulation
2012 * @dev: DRM device
2013 *
2014 * This function can be used as the
2015 * &drm_mode_config_funcs.output_poll_changed callback for drivers that only
2016 * need to call drm_fbdev.hotplug_event().
2017 */
2018void drm_fb_helper_output_poll_changed(struct drm_device *dev)
2019{
2020	drm_fb_helper_hotplug_event(dev->fb_helper);
2021}
2022EXPORT_SYMBOL(drm_fb_helper_output_poll_changed);