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/export.h>
34
35#include <drm/drm_atomic.h>
36#include <drm/drm_drv.h>
37#include <drm/drm_fb_helper.h>
38#include <drm/drm_fourcc.h>
39#include <drm/drm_framebuffer.h>
40#include <drm/drm_modeset_helper_vtables.h>
41#include <drm/drm_print.h>
42#include <drm/drm_vblank.h>
43
44#include "drm_internal.h"
45#include "drm_crtc_internal.h"
46
47static bool drm_fbdev_emulation = true;
48module_param_named(fbdev_emulation, drm_fbdev_emulation, bool, 0600);
49MODULE_PARM_DESC(fbdev_emulation,
50 "Enable legacy fbdev emulation [default=true]");
51
52static int drm_fbdev_overalloc = CONFIG_DRM_FBDEV_OVERALLOC;
53module_param(drm_fbdev_overalloc, int, 0444);
54MODULE_PARM_DESC(drm_fbdev_overalloc,
55 "Overallocation of the fbdev buffer (%) [default="
56 __MODULE_STRING(CONFIG_DRM_FBDEV_OVERALLOC) "]");
57
58/*
59 * In order to keep user-space compatibility, we want in certain use-cases
60 * to keep leaking the fbdev physical address to the user-space program
61 * handling the fbdev buffer.
62 *
63 * This is a bad habit, essentially kept to support closed-source OpenGL
64 * drivers that should really be moved into open-source upstream projects
65 * instead of using legacy physical addresses in user space to communicate
66 * with other out-of-tree kernel modules.
67 *
68 * This module_param *should* be removed as soon as possible and be
69 * considered as a broken and legacy behaviour from a modern fbdev device.
70 */
71static bool drm_leak_fbdev_smem;
72#if IS_ENABLED(CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM)
73module_param_unsafe(drm_leak_fbdev_smem, bool, 0600);
74MODULE_PARM_DESC(drm_leak_fbdev_smem,
75 "Allow unsafe leaking fbdev physical smem address [default=false]");
76#endif
77
78static LIST_HEAD(kernel_fb_helper_list);
79static DEFINE_MUTEX(kernel_fb_helper_lock);
80
81/**
82 * DOC: fbdev helpers
83 *
84 * The fb helper functions are useful to provide an fbdev on top of a drm kernel
85 * mode setting driver. They can be used mostly independently from the crtc
86 * helper functions used by many drivers to implement the kernel mode setting
87 * interfaces. Drivers that use one of the shared memory managers, TTM, SHMEM,
88 * DMA, should instead use the corresponding fbdev emulation.
89 *
90 * For suspend/resume consider using drm_mode_config_helper_suspend() and
91 * drm_mode_config_helper_resume() which takes care of fbdev as well.
92 *
93 * All other functions exported by the fb helper library can be used to
94 * implement the fbdev driver interface by the driver.
95 *
96 * It is possible, though perhaps somewhat tricky, to implement race-free
97 * hotplug detection using the fbdev helpers. The drm_fb_helper_prepare()
98 * helper must be called first to initialize the minimum required to make
99 * hotplug detection work. Drivers also need to make sure to properly set up
100 * the &drm_mode_config.funcs member. After calling drm_kms_helper_poll_init()
101 * it is safe to enable interrupts and start processing hotplug events. At the
102 * same time, drivers should initialize all modeset objects such as CRTCs,
103 * encoders and connectors. To finish up the fbdev helper initialization, the
104 * drm_fb_helper_init() function is called. To probe for all attached displays
105 * and set up an initial configuration using the detected hardware, drivers
106 * should call drm_fb_helper_initial_config().
107 *
108 * If &drm_framebuffer_funcs.dirty is set, the
109 * drm_fb_helper_{cfb,sys}_{write,fillrect,copyarea,imageblit} functions will
110 * accumulate changes and schedule &drm_fb_helper.dirty_work to run right
111 * away. This worker then calls the dirty() function ensuring that it will
112 * always run in process context since the fb_*() function could be running in
113 * atomic context. If drm_fb_helper_deferred_io() is used as the deferred_io
114 * callback it will also schedule dirty_work with the damage collected from the
115 * mmap page writes.
116 */
117
118static void drm_fb_helper_restore_lut_atomic(struct drm_crtc *crtc)
119{
120 uint16_t *r_base, *g_base, *b_base;
121
122 if (crtc->funcs->gamma_set == NULL)
123 return;
124
125 r_base = crtc->gamma_store;
126 g_base = r_base + crtc->gamma_size;
127 b_base = g_base + crtc->gamma_size;
128
129 crtc->funcs->gamma_set(crtc, r_base, g_base, b_base,
130 crtc->gamma_size, NULL);
131}
132
133/**
134 * drm_fb_helper_debug_enter - implementation for &fb_ops.fb_debug_enter
135 * @info: fbdev registered by the helper
136 */
137int drm_fb_helper_debug_enter(struct fb_info *info)
138{
139 struct drm_fb_helper *helper = info->par;
140 const struct drm_crtc_helper_funcs *funcs;
141 struct drm_mode_set *mode_set;
142
143 list_for_each_entry(helper, &kernel_fb_helper_list, kernel_fb_list) {
144 mutex_lock(&helper->client.modeset_mutex);
145 drm_client_for_each_modeset(mode_set, &helper->client) {
146 if (!mode_set->crtc->enabled)
147 continue;
148
149 funcs = mode_set->crtc->helper_private;
150 if (funcs->mode_set_base_atomic == NULL)
151 continue;
152
153 if (drm_drv_uses_atomic_modeset(dev: mode_set->crtc->dev))
154 continue;
155
156 funcs->mode_set_base_atomic(mode_set->crtc,
157 mode_set->fb,
158 mode_set->x,
159 mode_set->y,
160 ENTER_ATOMIC_MODE_SET);
161 }
162 mutex_unlock(lock: &helper->client.modeset_mutex);
163 }
164
165 return 0;
166}
167EXPORT_SYMBOL(drm_fb_helper_debug_enter);
168
169/**
170 * drm_fb_helper_debug_leave - implementation for &fb_ops.fb_debug_leave
171 * @info: fbdev registered by the helper
172 */
173int drm_fb_helper_debug_leave(struct fb_info *info)
174{
175 struct drm_fb_helper *helper = info->par;
176 struct drm_client_dev *client = &helper->client;
177 struct drm_device *dev = helper->dev;
178 struct drm_crtc *crtc;
179 const struct drm_crtc_helper_funcs *funcs;
180 struct drm_mode_set *mode_set;
181 struct drm_framebuffer *fb;
182
183 mutex_lock(&client->modeset_mutex);
184 drm_client_for_each_modeset(mode_set, client) {
185 crtc = mode_set->crtc;
186 if (drm_drv_uses_atomic_modeset(dev: crtc->dev))
187 continue;
188
189 funcs = crtc->helper_private;
190 fb = crtc->primary->fb;
191
192 if (!crtc->enabled)
193 continue;
194
195 if (!fb) {
196 drm_err(dev, "no fb to restore?\n");
197 continue;
198 }
199
200 if (funcs->mode_set_base_atomic == NULL)
201 continue;
202
203 drm_fb_helper_restore_lut_atomic(crtc: mode_set->crtc);
204 funcs->mode_set_base_atomic(mode_set->crtc, fb, crtc->x,
205 crtc->y, LEAVE_ATOMIC_MODE_SET);
206 }
207 mutex_unlock(lock: &client->modeset_mutex);
208
209 return 0;
210}
211EXPORT_SYMBOL(drm_fb_helper_debug_leave);
212
213static int
214__drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper,
215 bool force)
216{
217 bool do_delayed;
218 int ret;
219
220 if (!drm_fbdev_emulation || !fb_helper)
221 return -ENODEV;
222
223 if (READ_ONCE(fb_helper->deferred_setup))
224 return 0;
225
226 mutex_lock(&fb_helper->lock);
227 if (force) {
228 /*
229 * Yes this is the _locked version which expects the master lock
230 * to be held. But for forced restores we're intentionally
231 * racing here, see drm_fb_helper_set_par().
232 */
233 ret = drm_client_modeset_commit_locked(client: &fb_helper->client);
234 } else {
235 ret = drm_client_modeset_commit(client: &fb_helper->client);
236 }
237
238 do_delayed = fb_helper->delayed_hotplug;
239 if (do_delayed)
240 fb_helper->delayed_hotplug = false;
241 mutex_unlock(lock: &fb_helper->lock);
242
243 if (do_delayed)
244 drm_fb_helper_hotplug_event(fb_helper);
245
246 if (fb_helper->funcs->fb_restore)
247 fb_helper->funcs->fb_restore(fb_helper);
248
249 return ret;
250}
251
252/**
253 * drm_fb_helper_restore_fbdev_mode_unlocked - restore fbdev configuration
254 * @fb_helper: driver-allocated fbdev helper, can be NULL
255 * @force: ignore present DRM master
256 *
257 * This helper should be called from fbdev emulation's &drm_client_funcs.restore
258 * callback. It ensures that the user isn't greeted with a black screen when the
259 * userspace compositor releases the display device.
260 *
261 * Returns:
262 * 0 on success, or a negative errno code otherwise.
263 */
264int drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper, bool force)
265{
266 return __drm_fb_helper_restore_fbdev_mode_unlocked(fb_helper, force);
267}
268EXPORT_SYMBOL(drm_fb_helper_restore_fbdev_mode_unlocked);
269
270static void drm_fb_helper_dpms(struct fb_info *info, int dpms_mode)
271{
272 struct drm_fb_helper *fb_helper = info->par;
273
274 mutex_lock(&fb_helper->lock);
275 drm_client_modeset_dpms(client: &fb_helper->client, mode: dpms_mode);
276 mutex_unlock(lock: &fb_helper->lock);
277}
278
279/**
280 * drm_fb_helper_blank - implementation for &fb_ops.fb_blank
281 * @blank: desired blanking state
282 * @info: fbdev registered by the helper
283 */
284int drm_fb_helper_blank(int blank, struct fb_info *info)
285{
286 if (oops_in_progress)
287 return -EBUSY;
288
289 switch (blank) {
290 /* Display: On; HSync: On, VSync: On */
291 case FB_BLANK_UNBLANK:
292 drm_fb_helper_dpms(info, DRM_MODE_DPMS_ON);
293 break;
294 /* Display: Off; HSync: On, VSync: On */
295 case FB_BLANK_NORMAL:
296 drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY);
297 break;
298 /* Display: Off; HSync: Off, VSync: On */
299 case FB_BLANK_HSYNC_SUSPEND:
300 drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY);
301 break;
302 /* Display: Off; HSync: On, VSync: Off */
303 case FB_BLANK_VSYNC_SUSPEND:
304 drm_fb_helper_dpms(info, DRM_MODE_DPMS_SUSPEND);
305 break;
306 /* Display: Off; HSync: Off, VSync: Off */
307 case FB_BLANK_POWERDOWN:
308 drm_fb_helper_dpms(info, DRM_MODE_DPMS_OFF);
309 break;
310 }
311 return 0;
312}
313EXPORT_SYMBOL(drm_fb_helper_blank);
314
315static void drm_fb_helper_resume_worker(struct work_struct *work)
316{
317 struct drm_fb_helper *helper = container_of(work, struct drm_fb_helper,
318 resume_work);
319
320 console_lock();
321 fb_set_suspend(info: helper->info, state: 0);
322 console_unlock();
323}
324
325static void drm_fb_helper_fb_dirty(struct drm_fb_helper *helper)
326{
327 struct drm_device *dev = helper->dev;
328 struct drm_clip_rect *clip = &helper->damage_clip;
329 struct drm_clip_rect clip_copy;
330 unsigned long flags;
331 int ret;
332
333 mutex_lock(&helper->lock);
334 drm_client_modeset_wait_for_vblank(client: &helper->client, crtc_index: 0);
335 mutex_unlock(lock: &helper->lock);
336
337 if (drm_WARN_ON_ONCE(dev, !helper->funcs->fb_dirty))
338 return;
339
340 spin_lock_irqsave(&helper->damage_lock, flags);
341 clip_copy = *clip;
342 clip->x1 = clip->y1 = ~0;
343 clip->x2 = clip->y2 = 0;
344 spin_unlock_irqrestore(lock: &helper->damage_lock, flags);
345
346 ret = helper->funcs->fb_dirty(helper, &clip_copy);
347 if (ret)
348 goto err;
349
350 return;
351
352err:
353 /*
354 * Restore damage clip rectangle on errors. The next run
355 * of the damage worker will perform the update.
356 */
357 spin_lock_irqsave(&helper->damage_lock, flags);
358 clip->x1 = min_t(u32, clip->x1, clip_copy.x1);
359 clip->y1 = min_t(u32, clip->y1, clip_copy.y1);
360 clip->x2 = max_t(u32, clip->x2, clip_copy.x2);
361 clip->y2 = max_t(u32, clip->y2, clip_copy.y2);
362 spin_unlock_irqrestore(lock: &helper->damage_lock, flags);
363}
364
365static void drm_fb_helper_damage_work(struct work_struct *work)
366{
367 struct drm_fb_helper *helper = container_of(work, struct drm_fb_helper, damage_work);
368
369 if (helper->info->state != FBINFO_STATE_RUNNING)
370 return;
371
372 drm_fb_helper_fb_dirty(helper);
373}
374
375/**
376 * drm_fb_helper_prepare - setup a drm_fb_helper structure
377 * @dev: DRM device
378 * @helper: driver-allocated fbdev helper structure to set up
379 * @preferred_bpp: Preferred bits per pixel for the device.
380 * @funcs: pointer to structure of functions associate with this helper
381 *
382 * Sets up the bare minimum to make the framebuffer helper usable. This is
383 * useful to implement race-free initialization of the polling helpers.
384 */
385void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper,
386 unsigned int preferred_bpp,
387 const struct drm_fb_helper_funcs *funcs)
388{
389 /*
390 * Pick a preferred bpp of 32 if no value has been given. This
391 * will select XRGB8888 for the framebuffer formats. All drivers
392 * have to support XRGB8888 for backwards compatibility with legacy
393 * userspace, so it's the safe choice here.
394 *
395 * TODO: Replace struct drm_mode_config.preferred_depth and this
396 * bpp value with a preferred format that is given as struct
397 * drm_format_info. Then derive all other values from the
398 * format.
399 */
400 if (!preferred_bpp)
401 preferred_bpp = 32;
402
403 INIT_LIST_HEAD(list: &helper->kernel_fb_list);
404 spin_lock_init(&helper->damage_lock);
405 INIT_WORK(&helper->resume_work, drm_fb_helper_resume_worker);
406 INIT_WORK(&helper->damage_work, drm_fb_helper_damage_work);
407 helper->damage_clip.x1 = helper->damage_clip.y1 = ~0;
408 mutex_init(&helper->lock);
409 helper->funcs = funcs;
410 helper->dev = dev;
411 helper->preferred_bpp = preferred_bpp;
412}
413EXPORT_SYMBOL(drm_fb_helper_prepare);
414
415/**
416 * drm_fb_helper_unprepare - clean up a drm_fb_helper structure
417 * @fb_helper: driver-allocated fbdev helper structure to set up
418 *
419 * Cleans up the framebuffer helper. Inverse of drm_fb_helper_prepare().
420 */
421void drm_fb_helper_unprepare(struct drm_fb_helper *fb_helper)
422{
423 mutex_destroy(lock: &fb_helper->lock);
424}
425EXPORT_SYMBOL(drm_fb_helper_unprepare);
426
427/**
428 * drm_fb_helper_init - initialize a &struct drm_fb_helper
429 * @dev: drm device
430 * @fb_helper: driver-allocated fbdev helper structure to initialize
431 *
432 * This allocates the structures for the fbdev helper with the given limits.
433 * Note that this won't yet touch the hardware (through the driver interfaces)
434 * nor register the fbdev. This is only done in drm_fb_helper_initial_config()
435 * to allow driver writes more control over the exact init sequence.
436 *
437 * Drivers must call drm_fb_helper_prepare() before calling this function.
438 *
439 * RETURNS:
440 * Zero if everything went ok, nonzero otherwise.
441 */
442int drm_fb_helper_init(struct drm_device *dev,
443 struct drm_fb_helper *fb_helper)
444{
445 int ret;
446
447 /*
448 * If this is not the generic fbdev client, initialize a drm_client
449 * without callbacks so we can use the modesets.
450 */
451 if (!fb_helper->client.funcs) {
452 ret = drm_client_init(dev, client: &fb_helper->client, name: "drm_fb_helper", NULL);
453 if (ret)
454 return ret;
455 }
456
457 dev->fb_helper = fb_helper;
458
459 return 0;
460}
461EXPORT_SYMBOL(drm_fb_helper_init);
462
463static struct fb_info *drm_fb_helper_alloc_info(struct drm_fb_helper *fb_helper)
464{
465 struct device *dev = fb_helper->dev->dev;
466 struct fb_info *info;
467 int ret;
468
469 info = framebuffer_alloc(size: 0, dev);
470 if (!info)
471 return ERR_PTR(error: -ENOMEM);
472
473 if (!drm_leak_fbdev_smem)
474 info->flags |= FBINFO_HIDE_SMEM_START;
475
476 ret = fb_alloc_cmap(cmap: &info->cmap, len: 256, transp: 0);
477 if (ret)
478 goto err_release;
479
480 fb_helper->info = info;
481 info->skip_vt_switch = true;
482
483 info->skip_panic = drm_panic_is_enabled(dev: fb_helper->dev);
484 return info;
485
486err_release:
487 framebuffer_release(info);
488 return ERR_PTR(error: ret);
489}
490
491static void drm_fb_helper_release_info(struct drm_fb_helper *fb_helper)
492{
493 struct fb_info *info = fb_helper->info;
494
495 if (!info)
496 return;
497
498 fb_helper->info = NULL;
499
500 if (info->cmap.len)
501 fb_dealloc_cmap(cmap: &info->cmap);
502 framebuffer_release(info);
503}
504
505/**
506 * drm_fb_helper_unregister_info - unregister fb_info framebuffer device
507 * @fb_helper: driver-allocated fbdev helper, must not be NULL
508 *
509 * A wrapper around unregister_framebuffer, to release the fb_info
510 * framebuffer device. This must be called before releasing all resources for
511 * @fb_helper by calling drm_fb_helper_fini().
512 */
513void drm_fb_helper_unregister_info(struct drm_fb_helper *fb_helper)
514{
515 unregister_framebuffer(fb_info: fb_helper->info);
516}
517EXPORT_SYMBOL(drm_fb_helper_unregister_info);
518
519/**
520 * drm_fb_helper_fini - finialize a &struct drm_fb_helper
521 * @fb_helper: driver-allocated fbdev helper, can be NULL
522 *
523 * This cleans up all remaining resources associated with @fb_helper.
524 */
525void drm_fb_helper_fini(struct drm_fb_helper *fb_helper)
526{
527 if (!fb_helper)
528 return;
529
530 fb_helper->dev->fb_helper = NULL;
531
532 if (!drm_fbdev_emulation)
533 return;
534
535 cancel_work_sync(work: &fb_helper->resume_work);
536 cancel_work_sync(work: &fb_helper->damage_work);
537
538 drm_fb_helper_release_info(fb_helper);
539
540 mutex_lock(&kernel_fb_helper_lock);
541 if (!list_empty(head: &fb_helper->kernel_fb_list))
542 list_del(entry: &fb_helper->kernel_fb_list);
543 mutex_unlock(lock: &kernel_fb_helper_lock);
544
545 if (!fb_helper->client.funcs)
546 drm_client_release(client: &fb_helper->client);
547}
548EXPORT_SYMBOL(drm_fb_helper_fini);
549
550static void drm_fb_helper_add_damage_clip(struct drm_fb_helper *helper, u32 x, u32 y,
551 u32 width, u32 height)
552{
553 struct drm_clip_rect *clip = &helper->damage_clip;
554 unsigned long flags;
555
556 spin_lock_irqsave(&helper->damage_lock, flags);
557 clip->x1 = min_t(u32, clip->x1, x);
558 clip->y1 = min_t(u32, clip->y1, y);
559 clip->x2 = max_t(u32, clip->x2, x + width);
560 clip->y2 = max_t(u32, clip->y2, y + height);
561 spin_unlock_irqrestore(lock: &helper->damage_lock, flags);
562}
563
564static void drm_fb_helper_damage(struct drm_fb_helper *helper, u32 x, u32 y,
565 u32 width, u32 height)
566{
567 /*
568 * This function may be invoked by panic() to flush the frame
569 * buffer, where all CPUs except the panic CPU are stopped.
570 * During the following schedule_work(), the panic CPU needs
571 * the worker_pool lock, which might be held by a stopped CPU,
572 * causing schedule_work() and panic() to block. Return early on
573 * oops_in_progress to prevent this blocking.
574 */
575 if (oops_in_progress)
576 return;
577
578 drm_fb_helper_add_damage_clip(helper, x, y, width, height);
579
580 schedule_work(work: &helper->damage_work);
581}
582
583/*
584 * Convert memory region into area of scanlines and pixels per
585 * scanline. The parameters off and len must not reach beyond
586 * the end of the framebuffer.
587 */
588static void drm_fb_helper_memory_range_to_clip(struct fb_info *info, off_t off, size_t len,
589 struct drm_rect *clip)
590{
591 u32 line_length = info->fix.line_length;
592 u32 fb_height = info->var.yres;
593 off_t end = off + len;
594 u32 x1 = 0;
595 u32 y1 = off / line_length;
596 u32 x2 = info->var.xres;
597 u32 y2 = DIV_ROUND_UP(end, line_length);
598
599 /* Don't allow any of them beyond the bottom bound of display area */
600 if (y1 > fb_height)
601 y1 = fb_height;
602 if (y2 > fb_height)
603 y2 = fb_height;
604
605 if ((y2 - y1) == 1) {
606 /*
607 * We've only written to a single scanline. Try to reduce
608 * the number of horizontal pixels that need an update.
609 */
610 off_t bit_off = (off % line_length) * 8;
611 off_t bit_end = (end % line_length) * 8;
612
613 x1 = bit_off / info->var.bits_per_pixel;
614 x2 = DIV_ROUND_UP(bit_end, info->var.bits_per_pixel);
615 }
616
617 drm_rect_init(r: clip, x: x1, y: y1, width: x2 - x1, height: y2 - y1);
618}
619
620/* Don't use in new code. */
621void drm_fb_helper_damage_range(struct fb_info *info, off_t off, size_t len)
622{
623 struct drm_fb_helper *fb_helper = info->par;
624 struct drm_rect damage_area;
625
626 drm_fb_helper_memory_range_to_clip(info, off, len, clip: &damage_area);
627 drm_fb_helper_damage(helper: fb_helper, x: damage_area.x1, y: damage_area.y1,
628 width: drm_rect_width(r: &damage_area),
629 height: drm_rect_height(r: &damage_area));
630}
631EXPORT_SYMBOL(drm_fb_helper_damage_range);
632
633/* Don't use in new code. */
634void drm_fb_helper_damage_area(struct fb_info *info, u32 x, u32 y, u32 width, u32 height)
635{
636 struct drm_fb_helper *fb_helper = info->par;
637
638 drm_fb_helper_damage(helper: fb_helper, x, y, width, height);
639}
640EXPORT_SYMBOL(drm_fb_helper_damage_area);
641
642#ifdef CONFIG_FB_DEFERRED_IO
643/**
644 * drm_fb_helper_deferred_io() - fbdev deferred_io callback function
645 * @info: fb_info struct pointer
646 * @pagereflist: list of mmap framebuffer pages that have to be flushed
647 *
648 * This function is used as the &fb_deferred_io.deferred_io
649 * callback function for flushing the fbdev mmap writes.
650 */
651void drm_fb_helper_deferred_io(struct fb_info *info, struct list_head *pagereflist)
652{
653 struct drm_fb_helper *helper = info->par;
654 unsigned long start, end, min_off, max_off, total_size;
655 struct fb_deferred_io_pageref *pageref;
656 struct drm_rect damage_area;
657
658 min_off = ULONG_MAX;
659 max_off = 0;
660 list_for_each_entry(pageref, pagereflist, list) {
661 start = pageref->offset;
662 end = start + PAGE_SIZE;
663 min_off = min(min_off, start);
664 max_off = max(max_off, end);
665 }
666
667 /*
668 * As we can only track pages, we might reach beyond the end
669 * of the screen and account for non-existing scanlines. Hence,
670 * keep the covered memory area within the screen buffer.
671 */
672 if (info->screen_size)
673 total_size = info->screen_size;
674 else
675 total_size = info->fix.smem_len;
676 max_off = min(max_off, total_size);
677
678 if (min_off < max_off) {
679 drm_fb_helper_memory_range_to_clip(info, off: min_off, len: max_off - min_off, clip: &damage_area);
680 drm_fb_helper_damage(helper, x: damage_area.x1, y: damage_area.y1,
681 width: drm_rect_width(r: &damage_area),
682 height: drm_rect_height(r: &damage_area));
683 }
684}
685EXPORT_SYMBOL(drm_fb_helper_deferred_io);
686#endif
687
688/**
689 * drm_fb_helper_set_suspend - wrapper around fb_set_suspend
690 * @fb_helper: driver-allocated fbdev helper, can be NULL
691 * @suspend: whether to suspend or resume
692 *
693 * A wrapper around fb_set_suspend implemented by fbdev core.
694 * Use drm_fb_helper_set_suspend_unlocked() if you don't need to take
695 * the lock yourself
696 */
697void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper, bool suspend)
698{
699 if (!fb_helper || !fb_helper->info)
700 return;
701
702 if (fb_helper->funcs->fb_set_suspend)
703 fb_helper->funcs->fb_set_suspend(fb_helper, suspend);
704 else
705 fb_set_suspend(info: fb_helper->info, state: suspend);
706}
707EXPORT_SYMBOL(drm_fb_helper_set_suspend);
708
709/**
710 * drm_fb_helper_set_suspend_unlocked - wrapper around fb_set_suspend that also
711 * takes the console lock
712 * @fb_helper: driver-allocated fbdev helper, can be NULL
713 * @suspend: whether to suspend or resume
714 *
715 * A wrapper around fb_set_suspend() that takes the console lock. If the lock
716 * isn't available on resume, a worker is tasked with waiting for the lock
717 * to become available. The console lock can be pretty contented on resume
718 * due to all the printk activity.
719 *
720 * This function can be called multiple times with the same state since
721 * &fb_info.state is checked to see if fbdev is running or not before locking.
722 *
723 * Use drm_fb_helper_set_suspend() if you need to take the lock yourself.
724 */
725void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper,
726 bool suspend)
727{
728 if (!fb_helper || !fb_helper->info)
729 return;
730
731 /* make sure there's no pending/ongoing resume */
732 flush_work(work: &fb_helper->resume_work);
733
734 if (suspend) {
735 if (fb_helper->info->state != FBINFO_STATE_RUNNING)
736 return;
737
738 /*
739 * Cancel pending damage work. During GPU reset, VBlank
740 * interrupts are disabled and drm_fb_helper_fb_dirty()
741 * would wait for VBlank timeout otherwise.
742 */
743 cancel_work_sync(work: &fb_helper->damage_work);
744
745 console_lock();
746
747 } else {
748 if (fb_helper->info->state == FBINFO_STATE_RUNNING)
749 return;
750
751 if (!console_trylock()) {
752 schedule_work(work: &fb_helper->resume_work);
753 return;
754 }
755 }
756
757 drm_fb_helper_set_suspend(fb_helper, suspend);
758 console_unlock();
759}
760EXPORT_SYMBOL(drm_fb_helper_set_suspend_unlocked);
761
762static int setcmap_pseudo_palette(struct fb_cmap *cmap, struct fb_info *info)
763{
764 u32 *palette = (u32 *)info->pseudo_palette;
765 int i;
766
767 if (cmap->start + cmap->len > 16)
768 return -EINVAL;
769
770 for (i = 0; i < cmap->len; ++i) {
771 u16 red = cmap->red[i];
772 u16 green = cmap->green[i];
773 u16 blue = cmap->blue[i];
774 u32 value;
775
776 red >>= 16 - info->var.red.length;
777 green >>= 16 - info->var.green.length;
778 blue >>= 16 - info->var.blue.length;
779 value = (red << info->var.red.offset) |
780 (green << info->var.green.offset) |
781 (blue << info->var.blue.offset);
782 if (info->var.transp.length > 0) {
783 u32 mask = (1 << info->var.transp.length) - 1;
784
785 mask <<= info->var.transp.offset;
786 value |= mask;
787 }
788 palette[cmap->start + i] = value;
789 }
790
791 return 0;
792}
793
794static int setcmap_legacy(struct fb_cmap *cmap, struct fb_info *info)
795{
796 struct drm_fb_helper *fb_helper = info->par;
797 struct drm_mode_set *modeset;
798 struct drm_crtc *crtc;
799 u16 *r, *g, *b;
800 int ret = 0;
801
802 drm_modeset_lock_all(dev: fb_helper->dev);
803 drm_client_for_each_modeset(modeset, &fb_helper->client) {
804 crtc = modeset->crtc;
805 if (!crtc->funcs->gamma_set || !crtc->gamma_size) {
806 ret = -EINVAL;
807 goto out;
808 }
809
810 if (cmap->start + cmap->len > crtc->gamma_size) {
811 ret = -EINVAL;
812 goto out;
813 }
814
815 r = crtc->gamma_store;
816 g = r + crtc->gamma_size;
817 b = g + crtc->gamma_size;
818
819 memcpy(r + cmap->start, cmap->red, cmap->len * sizeof(*r));
820 memcpy(g + cmap->start, cmap->green, cmap->len * sizeof(*g));
821 memcpy(b + cmap->start, cmap->blue, cmap->len * sizeof(*b));
822
823 ret = crtc->funcs->gamma_set(crtc, r, g, b,
824 crtc->gamma_size, NULL);
825 if (ret)
826 goto out;
827 }
828out:
829 drm_modeset_unlock_all(dev: fb_helper->dev);
830
831 return ret;
832}
833
834static struct drm_property_blob *setcmap_new_gamma_lut(struct drm_crtc *crtc,
835 struct fb_cmap *cmap)
836{
837 struct drm_device *dev = crtc->dev;
838 struct drm_property_blob *gamma_lut;
839 struct drm_color_lut *lut;
840 int size = crtc->gamma_size;
841 int i;
842
843 if (!size || cmap->start + cmap->len > size)
844 return ERR_PTR(error: -EINVAL);
845
846 gamma_lut = drm_property_create_blob(dev, length: sizeof(*lut) * size, NULL);
847 if (IS_ERR(ptr: gamma_lut))
848 return gamma_lut;
849
850 lut = gamma_lut->data;
851 if (cmap->start || cmap->len != size) {
852 u16 *r = crtc->gamma_store;
853 u16 *g = r + crtc->gamma_size;
854 u16 *b = g + crtc->gamma_size;
855
856 for (i = 0; i < cmap->start; i++) {
857 lut[i].red = r[i];
858 lut[i].green = g[i];
859 lut[i].blue = b[i];
860 }
861 for (i = cmap->start + cmap->len; i < size; i++) {
862 lut[i].red = r[i];
863 lut[i].green = g[i];
864 lut[i].blue = b[i];
865 }
866 }
867
868 for (i = 0; i < cmap->len; i++) {
869 lut[cmap->start + i].red = cmap->red[i];
870 lut[cmap->start + i].green = cmap->green[i];
871 lut[cmap->start + i].blue = cmap->blue[i];
872 }
873
874 return gamma_lut;
875}
876
877static int setcmap_atomic(struct fb_cmap *cmap, struct fb_info *info)
878{
879 struct drm_fb_helper *fb_helper = info->par;
880 struct drm_device *dev = fb_helper->dev;
881 struct drm_property_blob *gamma_lut = NULL;
882 struct drm_modeset_acquire_ctx ctx;
883 struct drm_crtc_state *crtc_state;
884 struct drm_atomic_state *state;
885 struct drm_mode_set *modeset;
886 struct drm_crtc *crtc;
887 u16 *r, *g, *b;
888 bool replaced;
889 int ret = 0;
890
891 drm_modeset_acquire_init(ctx: &ctx, flags: 0);
892
893 state = drm_atomic_state_alloc(dev);
894 if (!state) {
895 ret = -ENOMEM;
896 goto out_ctx;
897 }
898
899 state->acquire_ctx = &ctx;
900retry:
901 drm_client_for_each_modeset(modeset, &fb_helper->client) {
902 crtc = modeset->crtc;
903
904 if (!gamma_lut)
905 gamma_lut = setcmap_new_gamma_lut(crtc, cmap);
906 if (IS_ERR(ptr: gamma_lut)) {
907 ret = PTR_ERR(ptr: gamma_lut);
908 gamma_lut = NULL;
909 goto out_state;
910 }
911
912 crtc_state = drm_atomic_get_crtc_state(state, crtc);
913 if (IS_ERR(ptr: crtc_state)) {
914 ret = PTR_ERR(ptr: crtc_state);
915 goto out_state;
916 }
917
918 /*
919 * FIXME: This always uses gamma_lut. Some HW have only
920 * degamma_lut, in which case we should reset gamma_lut and set
921 * degamma_lut. See drm_crtc_legacy_gamma_set().
922 */
923 replaced = drm_property_replace_blob(blob: &crtc_state->degamma_lut,
924 NULL);
925 replaced |= drm_property_replace_blob(blob: &crtc_state->ctm, NULL);
926 replaced |= drm_property_replace_blob(blob: &crtc_state->gamma_lut,
927 new_blob: gamma_lut);
928 crtc_state->color_mgmt_changed |= replaced;
929 }
930
931 ret = drm_atomic_commit(state);
932 if (ret)
933 goto out_state;
934
935 drm_client_for_each_modeset(modeset, &fb_helper->client) {
936 crtc = modeset->crtc;
937
938 r = crtc->gamma_store;
939 g = r + crtc->gamma_size;
940 b = g + crtc->gamma_size;
941
942 memcpy(r + cmap->start, cmap->red, cmap->len * sizeof(*r));
943 memcpy(g + cmap->start, cmap->green, cmap->len * sizeof(*g));
944 memcpy(b + cmap->start, cmap->blue, cmap->len * sizeof(*b));
945 }
946
947out_state:
948 if (ret == -EDEADLK)
949 goto backoff;
950
951 drm_property_blob_put(blob: gamma_lut);
952 drm_atomic_state_put(state);
953out_ctx:
954 drm_modeset_drop_locks(ctx: &ctx);
955 drm_modeset_acquire_fini(ctx: &ctx);
956
957 return ret;
958
959backoff:
960 drm_atomic_state_clear(state);
961 drm_modeset_backoff(ctx: &ctx);
962 goto retry;
963}
964
965/**
966 * drm_fb_helper_setcmap - implementation for &fb_ops.fb_setcmap
967 * @cmap: cmap to set
968 * @info: fbdev registered by the helper
969 */
970int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info)
971{
972 struct drm_fb_helper *fb_helper = info->par;
973 struct drm_device *dev = fb_helper->dev;
974 int ret;
975
976 if (oops_in_progress)
977 return -EBUSY;
978
979 mutex_lock(&fb_helper->lock);
980
981 if (!drm_master_internal_acquire(dev)) {
982 ret = -EBUSY;
983 goto unlock;
984 }
985
986 mutex_lock(&fb_helper->client.modeset_mutex);
987 if (info->fix.visual == FB_VISUAL_TRUECOLOR)
988 ret = setcmap_pseudo_palette(cmap, info);
989 else if (drm_drv_uses_atomic_modeset(dev: fb_helper->dev))
990 ret = setcmap_atomic(cmap, info);
991 else
992 ret = setcmap_legacy(cmap, info);
993 mutex_unlock(lock: &fb_helper->client.modeset_mutex);
994
995 drm_master_internal_release(dev);
996unlock:
997 mutex_unlock(lock: &fb_helper->lock);
998
999 return ret;
1000}
1001EXPORT_SYMBOL(drm_fb_helper_setcmap);
1002
1003/**
1004 * drm_fb_helper_ioctl - legacy ioctl implementation
1005 * @info: fbdev registered by the helper
1006 * @cmd: ioctl command
1007 * @arg: ioctl argument
1008 *
1009 * A helper to implement the standard fbdev ioctl. Only
1010 * FBIO_WAITFORVSYNC is implemented for now.
1011 */
1012int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd,
1013 unsigned long arg)
1014{
1015 struct drm_fb_helper *fb_helper = info->par;
1016 int ret = 0;
1017
1018 guard(mutex)(T: &fb_helper->lock);
1019
1020 switch (cmd) {
1021 case FBIO_WAITFORVSYNC:
1022 /*
1023 * Only consider the first CRTC.
1024 *
1025 * This ioctl is supposed to take the CRTC number as
1026 * an argument, but in fbdev times, what that number
1027 * was supposed to be was quite unclear, different
1028 * drivers were passing that argument differently
1029 * (some by reference, some by value), and most of the
1030 * userspace applications were just hardcoding 0 as an
1031 * argument.
1032 *
1033 * The first CRTC should be the integrated panel on
1034 * most drivers, so this is the best choice we can
1035 * make. If we're not smart enough here, one should
1036 * just consider switch the userspace to KMS.
1037 */
1038 ret = drm_client_modeset_wait_for_vblank(client: &fb_helper->client, crtc_index: 0);
1039 break;
1040 default:
1041 ret = -ENOTTY;
1042 }
1043
1044 return ret;
1045}
1046EXPORT_SYMBOL(drm_fb_helper_ioctl);
1047
1048static bool drm_fb_pixel_format_equal(const struct fb_var_screeninfo *var_1,
1049 const struct fb_var_screeninfo *var_2)
1050{
1051 return var_1->bits_per_pixel == var_2->bits_per_pixel &&
1052 var_1->grayscale == var_2->grayscale &&
1053 var_1->red.offset == var_2->red.offset &&
1054 var_1->red.length == var_2->red.length &&
1055 var_1->red.msb_right == var_2->red.msb_right &&
1056 var_1->green.offset == var_2->green.offset &&
1057 var_1->green.length == var_2->green.length &&
1058 var_1->green.msb_right == var_2->green.msb_right &&
1059 var_1->blue.offset == var_2->blue.offset &&
1060 var_1->blue.length == var_2->blue.length &&
1061 var_1->blue.msb_right == var_2->blue.msb_right &&
1062 var_1->transp.offset == var_2->transp.offset &&
1063 var_1->transp.length == var_2->transp.length &&
1064 var_1->transp.msb_right == var_2->transp.msb_right;
1065}
1066
1067static void drm_fb_helper_fill_pixel_fmt(struct fb_var_screeninfo *var,
1068 const struct drm_format_info *format)
1069{
1070 u8 depth = format->depth;
1071
1072 if (format->is_color_indexed) {
1073 var->red.offset = 0;
1074 var->green.offset = 0;
1075 var->blue.offset = 0;
1076 var->red.length = depth;
1077 var->green.length = depth;
1078 var->blue.length = depth;
1079 var->transp.offset = 0;
1080 var->transp.length = 0;
1081 return;
1082 }
1083
1084 switch (depth) {
1085 case 15:
1086 var->red.offset = 10;
1087 var->green.offset = 5;
1088 var->blue.offset = 0;
1089 var->red.length = 5;
1090 var->green.length = 5;
1091 var->blue.length = 5;
1092 var->transp.offset = 15;
1093 var->transp.length = 1;
1094 break;
1095 case 16:
1096 var->red.offset = 11;
1097 var->green.offset = 5;
1098 var->blue.offset = 0;
1099 var->red.length = 5;
1100 var->green.length = 6;
1101 var->blue.length = 5;
1102 var->transp.offset = 0;
1103 break;
1104 case 24:
1105 var->red.offset = 16;
1106 var->green.offset = 8;
1107 var->blue.offset = 0;
1108 var->red.length = 8;
1109 var->green.length = 8;
1110 var->blue.length = 8;
1111 var->transp.offset = 0;
1112 var->transp.length = 0;
1113 break;
1114 case 32:
1115 var->red.offset = 16;
1116 var->green.offset = 8;
1117 var->blue.offset = 0;
1118 var->red.length = 8;
1119 var->green.length = 8;
1120 var->blue.length = 8;
1121 var->transp.offset = 24;
1122 var->transp.length = 8;
1123 break;
1124 default:
1125 break;
1126 }
1127}
1128
1129static void __fill_var(struct fb_var_screeninfo *var, struct fb_info *info,
1130 struct drm_framebuffer *fb)
1131{
1132 int i;
1133
1134 var->xres_virtual = fb->width;
1135 var->yres_virtual = fb->height;
1136 var->accel_flags = 0;
1137 var->bits_per_pixel = drm_format_info_bpp(info: fb->format, plane: 0);
1138
1139 var->height = info->var.height;
1140 var->width = info->var.width;
1141
1142 var->left_margin = var->right_margin = 0;
1143 var->upper_margin = var->lower_margin = 0;
1144 var->hsync_len = var->vsync_len = 0;
1145 var->sync = var->vmode = 0;
1146 var->rotate = 0;
1147 var->colorspace = 0;
1148 for (i = 0; i < 4; i++)
1149 var->reserved[i] = 0;
1150}
1151
1152/**
1153 * drm_fb_helper_check_var - implementation for &fb_ops.fb_check_var
1154 * @var: screeninfo to check
1155 * @info: fbdev registered by the helper
1156 */
1157int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
1158 struct fb_info *info)
1159{
1160 struct drm_fb_helper *fb_helper = info->par;
1161 struct drm_framebuffer *fb = fb_helper->fb;
1162 const struct drm_format_info *format = fb->format;
1163 struct drm_device *dev = fb_helper->dev;
1164 unsigned int bpp;
1165
1166 if (in_dbg_master())
1167 return -EINVAL;
1168
1169 if (var->pixclock != 0) {
1170 drm_dbg_kms(dev, "fbdev emulation doesn't support changing the pixel clock, value of pixclock is ignored\n");
1171 var->pixclock = 0;
1172 }
1173
1174 switch (format->format) {
1175 case DRM_FORMAT_C1:
1176 case DRM_FORMAT_C2:
1177 case DRM_FORMAT_C4:
1178 /* supported format with sub-byte pixels */
1179 break;
1180
1181 default:
1182 if ((drm_format_info_block_width(info: format, plane: 0) > 1) ||
1183 (drm_format_info_block_height(info: format, plane: 0) > 1))
1184 return -EINVAL;
1185 break;
1186 }
1187
1188 /*
1189 * Changes struct fb_var_screeninfo are currently not pushed back
1190 * to KMS, hence fail if different settings are requested.
1191 */
1192 bpp = drm_format_info_bpp(info: format, plane: 0);
1193 if (var->bits_per_pixel > bpp ||
1194 var->xres > fb->width || var->yres > fb->height ||
1195 var->xres_virtual > fb->width || var->yres_virtual > fb->height) {
1196 drm_dbg_kms(dev, "fb requested width/height/bpp can't fit in current fb "
1197 "request %dx%d-%d (virtual %dx%d) > %dx%d-%d\n",
1198 var->xres, var->yres, var->bits_per_pixel,
1199 var->xres_virtual, var->yres_virtual,
1200 fb->width, fb->height, bpp);
1201 return -EINVAL;
1202 }
1203
1204 __fill_var(var, info, fb);
1205
1206 /*
1207 * fb_pan_display() validates this, but fb_set_par() doesn't and just
1208 * falls over. Note that __fill_var above adjusts y/res_virtual.
1209 */
1210 if (var->yoffset > var->yres_virtual - var->yres ||
1211 var->xoffset > var->xres_virtual - var->xres)
1212 return -EINVAL;
1213
1214 /* We neither support grayscale nor FOURCC (also stored in here). */
1215 if (var->grayscale > 0)
1216 return -EINVAL;
1217
1218 if (var->nonstd)
1219 return -EINVAL;
1220
1221 /*
1222 * Workaround for SDL 1.2, which is known to be setting all pixel format
1223 * fields values to zero in some cases. We treat this situation as a
1224 * kind of "use some reasonable autodetected values".
1225 */
1226 if (!var->red.offset && !var->green.offset &&
1227 !var->blue.offset && !var->transp.offset &&
1228 !var->red.length && !var->green.length &&
1229 !var->blue.length && !var->transp.length &&
1230 !var->red.msb_right && !var->green.msb_right &&
1231 !var->blue.msb_right && !var->transp.msb_right) {
1232 drm_fb_helper_fill_pixel_fmt(var, format);
1233 }
1234
1235 /*
1236 * drm fbdev emulation doesn't support changing the pixel format at all,
1237 * so reject all pixel format changing requests.
1238 */
1239 if (!drm_fb_pixel_format_equal(var_1: var, var_2: &info->var)) {
1240 drm_dbg_kms(dev, "fbdev emulation doesn't support changing the pixel format\n");
1241 return -EINVAL;
1242 }
1243
1244 return 0;
1245}
1246EXPORT_SYMBOL(drm_fb_helper_check_var);
1247
1248/**
1249 * drm_fb_helper_set_par - implementation for &fb_ops.fb_set_par
1250 * @info: fbdev registered by the helper
1251 *
1252 * This will let fbcon do the mode init and is called at initialization time by
1253 * the fbdev core when registering the driver, and later on through the hotplug
1254 * callback.
1255 */
1256int drm_fb_helper_set_par(struct fb_info *info)
1257{
1258 struct drm_fb_helper *fb_helper = info->par;
1259 struct fb_var_screeninfo *var = &info->var;
1260 bool force;
1261
1262 if (oops_in_progress)
1263 return -EBUSY;
1264
1265 /*
1266 * Normally we want to make sure that a kms master takes precedence over
1267 * fbdev, to avoid fbdev flickering and occasionally stealing the
1268 * display status. But Xorg first sets the vt back to text mode using
1269 * the KDSET IOCTL with KD_TEXT, and only after that drops the master
1270 * status when exiting.
1271 *
1272 * In the past this was caught by drm_fb_helper_restore_fbdev_mode_unlocked(),
1273 * but on modern systems where logind always keeps a drm fd open to
1274 * orchestrate the vt switching, this doesn't work.
1275 *
1276 * To not break the userspace ABI we have this special case here, which
1277 * is only used for the above case. Everything else uses the normal
1278 * commit function, which ensures that we never steal the display from
1279 * an active drm master.
1280 */
1281 force = var->activate & FB_ACTIVATE_KD_TEXT;
1282
1283 __drm_fb_helper_restore_fbdev_mode_unlocked(fb_helper, force);
1284
1285 return 0;
1286}
1287EXPORT_SYMBOL(drm_fb_helper_set_par);
1288
1289static void pan_set(struct drm_fb_helper *fb_helper, int dx, int dy)
1290{
1291 struct drm_mode_set *mode_set;
1292
1293 mutex_lock(&fb_helper->client.modeset_mutex);
1294 drm_client_for_each_modeset(mode_set, &fb_helper->client) {
1295 mode_set->x += dx;
1296 mode_set->y += dy;
1297 }
1298 mutex_unlock(lock: &fb_helper->client.modeset_mutex);
1299}
1300
1301static int pan_display_atomic(struct fb_var_screeninfo *var,
1302 struct fb_info *info)
1303{
1304 struct drm_fb_helper *fb_helper = info->par;
1305 int ret, dx, dy;
1306
1307 dx = var->xoffset - info->var.xoffset;
1308 dy = var->yoffset - info->var.yoffset;
1309 pan_set(fb_helper, dx, dy);
1310
1311 ret = drm_client_modeset_commit_locked(client: &fb_helper->client);
1312 if (!ret) {
1313 info->var.xoffset = var->xoffset;
1314 info->var.yoffset = var->yoffset;
1315 } else
1316 pan_set(fb_helper, dx: -dx, dy: -dy);
1317
1318 return ret;
1319}
1320
1321static int pan_display_legacy(struct fb_var_screeninfo *var,
1322 struct fb_info *info)
1323{
1324 struct drm_fb_helper *fb_helper = info->par;
1325 struct drm_client_dev *client = &fb_helper->client;
1326 struct drm_mode_set *modeset;
1327 int ret = 0;
1328
1329 mutex_lock(&client->modeset_mutex);
1330 drm_modeset_lock_all(dev: fb_helper->dev);
1331 drm_client_for_each_modeset(modeset, client) {
1332 modeset->x = var->xoffset;
1333 modeset->y = var->yoffset;
1334
1335 if (modeset->num_connectors) {
1336 ret = drm_mode_set_config_internal(set: modeset);
1337 if (!ret) {
1338 info->var.xoffset = var->xoffset;
1339 info->var.yoffset = var->yoffset;
1340 }
1341 }
1342 }
1343 drm_modeset_unlock_all(dev: fb_helper->dev);
1344 mutex_unlock(lock: &client->modeset_mutex);
1345
1346 return ret;
1347}
1348
1349/**
1350 * drm_fb_helper_pan_display - implementation for &fb_ops.fb_pan_display
1351 * @var: updated screen information
1352 * @info: fbdev registered by the helper
1353 */
1354int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
1355 struct fb_info *info)
1356{
1357 struct drm_fb_helper *fb_helper = info->par;
1358 struct drm_device *dev = fb_helper->dev;
1359 int ret;
1360
1361 if (oops_in_progress)
1362 return -EBUSY;
1363
1364 mutex_lock(&fb_helper->lock);
1365 if (!drm_master_internal_acquire(dev)) {
1366 ret = -EBUSY;
1367 goto unlock;
1368 }
1369
1370 if (drm_drv_uses_atomic_modeset(dev))
1371 ret = pan_display_atomic(var, info);
1372 else
1373 ret = pan_display_legacy(var, info);
1374
1375 drm_master_internal_release(dev);
1376unlock:
1377 mutex_unlock(lock: &fb_helper->lock);
1378
1379 return ret;
1380}
1381EXPORT_SYMBOL(drm_fb_helper_pan_display);
1382
1383static uint32_t drm_fb_helper_find_format(struct drm_fb_helper *fb_helper, const uint32_t *formats,
1384 size_t format_count, unsigned int color_mode)
1385{
1386 struct drm_device *dev = fb_helper->dev;
1387 uint32_t format;
1388 size_t i;
1389
1390 format = drm_driver_color_mode_format(dev, color_mode);
1391 if (!format) {
1392 drm_info(dev, "unsupported color mode of %d\n", color_mode);
1393 return DRM_FORMAT_INVALID;
1394 }
1395
1396 for (i = 0; i < format_count; ++i) {
1397 if (formats[i] == format)
1398 return format;
1399 }
1400 drm_warn(dev, "format %p4cc not supported\n", &format);
1401
1402 return DRM_FORMAT_INVALID;
1403}
1404
1405static int __drm_fb_helper_find_sizes(struct drm_fb_helper *fb_helper,
1406 struct drm_fb_helper_surface_size *sizes)
1407{
1408 struct drm_client_dev *client = &fb_helper->client;
1409 struct drm_device *dev = fb_helper->dev;
1410 int crtc_count = 0;
1411 struct drm_connector_list_iter conn_iter;
1412 struct drm_connector *connector;
1413 struct drm_mode_set *mode_set;
1414 uint32_t surface_format = DRM_FORMAT_INVALID;
1415 const struct drm_format_info *info;
1416
1417 memset(sizes, 0, sizeof(*sizes));
1418 sizes->fb_width = (u32)-1;
1419 sizes->fb_height = (u32)-1;
1420
1421 drm_client_for_each_modeset(mode_set, client) {
1422 struct drm_crtc *crtc = mode_set->crtc;
1423 struct drm_plane *plane = crtc->primary;
1424
1425 drm_dbg_kms(dev, "test CRTC %u primary plane\n", drm_crtc_index(crtc));
1426
1427 drm_connector_list_iter_begin(dev: fb_helper->dev, iter: &conn_iter);
1428 drm_client_for_each_connector_iter(connector, &conn_iter) {
1429 struct drm_cmdline_mode *cmdline_mode = &connector->cmdline_mode;
1430
1431 if (!cmdline_mode->bpp_specified)
1432 continue;
1433
1434 surface_format = drm_fb_helper_find_format(fb_helper,
1435 formats: plane->format_types,
1436 format_count: plane->format_count,
1437 color_mode: cmdline_mode->bpp);
1438 if (surface_format != DRM_FORMAT_INVALID)
1439 break; /* found supported format */
1440 }
1441 drm_connector_list_iter_end(iter: &conn_iter);
1442
1443 if (surface_format != DRM_FORMAT_INVALID)
1444 break; /* found supported format */
1445
1446 /* try preferred color mode */
1447 surface_format = drm_fb_helper_find_format(fb_helper,
1448 formats: plane->format_types,
1449 format_count: plane->format_count,
1450 color_mode: fb_helper->preferred_bpp);
1451 if (surface_format != DRM_FORMAT_INVALID)
1452 break; /* found supported format */
1453 }
1454
1455 if (surface_format == DRM_FORMAT_INVALID) {
1456 /*
1457 * If none of the given color modes works, fall back
1458 * to XRGB8888. Drivers are expected to provide this
1459 * format for compatibility with legacy applications.
1460 */
1461 drm_warn(dev, "No compatible format found\n");
1462 surface_format = drm_driver_legacy_fb_format(dev, bpp: 32, depth: 24);
1463 }
1464
1465 info = drm_format_info(format: surface_format);
1466 sizes->surface_bpp = drm_format_info_bpp(info, plane: 0);
1467 sizes->surface_depth = info->depth;
1468
1469 /* first up get a count of crtcs now in use and new min/maxes width/heights */
1470 crtc_count = 0;
1471 drm_client_for_each_modeset(mode_set, client) {
1472 struct drm_display_mode *desired_mode;
1473 int x, y, j;
1474 /* in case of tile group, are we the last tile vert or horiz?
1475 * If no tile group you are always the last one both vertically
1476 * and horizontally
1477 */
1478 bool lastv = true, lasth = true;
1479
1480 desired_mode = mode_set->mode;
1481
1482 if (!desired_mode)
1483 continue;
1484
1485 crtc_count++;
1486
1487 x = mode_set->x;
1488 y = mode_set->y;
1489
1490 sizes->surface_width =
1491 max_t(u32, desired_mode->hdisplay + x, sizes->surface_width);
1492 sizes->surface_height =
1493 max_t(u32, desired_mode->vdisplay + y, sizes->surface_height);
1494
1495 for (j = 0; j < mode_set->num_connectors; j++) {
1496 struct drm_connector *connector = mode_set->connectors[j];
1497
1498 if (connector->has_tile &&
1499 desired_mode->hdisplay == connector->tile_h_size &&
1500 desired_mode->vdisplay == connector->tile_v_size) {
1501 lasth = (connector->tile_h_loc == (connector->num_h_tile - 1));
1502 lastv = (connector->tile_v_loc == (connector->num_v_tile - 1));
1503 /* cloning to multiple tiles is just crazy-talk, so: */
1504 break;
1505 }
1506 }
1507
1508 if (lasth)
1509 sizes->fb_width = min_t(u32, desired_mode->hdisplay + x, sizes->fb_width);
1510 if (lastv)
1511 sizes->fb_height = min_t(u32, desired_mode->vdisplay + y, sizes->fb_height);
1512 }
1513
1514 if (crtc_count == 0 || sizes->fb_width == -1 || sizes->fb_height == -1) {
1515 drm_info(dev, "Cannot find any crtc or sizes\n");
1516 return -EAGAIN;
1517 }
1518
1519 return 0;
1520}
1521
1522static int drm_fb_helper_find_sizes(struct drm_fb_helper *fb_helper,
1523 struct drm_fb_helper_surface_size *sizes)
1524{
1525 struct drm_client_dev *client = &fb_helper->client;
1526 struct drm_device *dev = fb_helper->dev;
1527 struct drm_mode_config *config = &dev->mode_config;
1528 int ret;
1529
1530 mutex_lock(&client->modeset_mutex);
1531 ret = __drm_fb_helper_find_sizes(fb_helper, sizes);
1532 mutex_unlock(lock: &client->modeset_mutex);
1533
1534 if (ret)
1535 return ret;
1536
1537 /* Handle our overallocation */
1538 sizes->surface_height *= drm_fbdev_overalloc;
1539 sizes->surface_height /= 100;
1540 if (sizes->surface_height > config->max_height) {
1541 drm_dbg_kms(dev, "Fbdev over-allocation too large; clamping height to %d\n",
1542 config->max_height);
1543 sizes->surface_height = config->max_height;
1544 }
1545
1546 return 0;
1547}
1548
1549/*
1550 * Allocates the backing storage and sets up the fbdev info structure through
1551 * the ->fbdev_probe callback.
1552 */
1553static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper)
1554{
1555 struct drm_client_dev *client = &fb_helper->client;
1556 struct drm_device *dev = fb_helper->dev;
1557 struct drm_fb_helper_surface_size sizes;
1558 int ret;
1559
1560 if (drm_WARN_ON(dev, !dev->driver->fbdev_probe))
1561 return -EINVAL;
1562
1563 ret = drm_fb_helper_find_sizes(fb_helper, sizes: &sizes);
1564 if (ret) {
1565 /* First time: disable all crtc's.. */
1566 if (!fb_helper->deferred_setup)
1567 drm_client_modeset_commit(client);
1568 return ret;
1569 }
1570
1571 /* push down into drivers */
1572 ret = dev->driver->fbdev_probe(fb_helper, &sizes);
1573 if (ret < 0)
1574 return ret;
1575
1576 strcpy(p: fb_helper->fb->comm, q: "[fbcon]");
1577
1578 return 0;
1579}
1580
1581static void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
1582 bool is_color_indexed)
1583{
1584 info->fix.type = FB_TYPE_PACKED_PIXELS;
1585 info->fix.visual = is_color_indexed ? FB_VISUAL_PSEUDOCOLOR
1586 : FB_VISUAL_TRUECOLOR;
1587 info->fix.mmio_start = 0;
1588 info->fix.mmio_len = 0;
1589 info->fix.type_aux = 0;
1590 info->fix.xpanstep = 1; /* doing it in hw */
1591 info->fix.ypanstep = 1; /* doing it in hw */
1592 info->fix.ywrapstep = 0;
1593 info->fix.accel = FB_ACCEL_NONE;
1594
1595 info->fix.line_length = pitch;
1596}
1597
1598static void drm_fb_helper_fill_var(struct fb_info *info,
1599 struct drm_fb_helper *fb_helper,
1600 uint32_t fb_width, uint32_t fb_height)
1601{
1602 struct drm_framebuffer *fb = fb_helper->fb;
1603 const struct drm_format_info *format = fb->format;
1604
1605 switch (format->format) {
1606 case DRM_FORMAT_C1:
1607 case DRM_FORMAT_C2:
1608 case DRM_FORMAT_C4:
1609 /* supported format with sub-byte pixels */
1610 break;
1611
1612 default:
1613 WARN_ON((drm_format_info_block_width(format, 0) > 1) ||
1614 (drm_format_info_block_height(format, 0) > 1));
1615 break;
1616 }
1617
1618 info->pseudo_palette = fb_helper->pseudo_palette;
1619 info->var.xoffset = 0;
1620 info->var.yoffset = 0;
1621 __fill_var(var: &info->var, info, fb);
1622 info->var.activate = FB_ACTIVATE_NOW;
1623
1624 drm_fb_helper_fill_pixel_fmt(var: &info->var, format);
1625
1626 info->var.xres = fb_width;
1627 info->var.yres = fb_height;
1628}
1629
1630/**
1631 * drm_fb_helper_fill_info - initializes fbdev information
1632 * @info: fbdev instance to set up
1633 * @fb_helper: fb helper instance to use as template
1634 * @sizes: describes fbdev size and scanout surface size
1635 *
1636 * Sets up the variable and fixed fbdev metainformation from the given fb helper
1637 * instance and the drm framebuffer allocated in &drm_fb_helper.fb.
1638 *
1639 * Drivers should call this (or their equivalent setup code) from their
1640 * &drm_driver.fbdev_probe callback after having allocated the fbdev
1641 * backing storage framebuffer.
1642 */
1643void drm_fb_helper_fill_info(struct fb_info *info,
1644 struct drm_fb_helper *fb_helper,
1645 struct drm_fb_helper_surface_size *sizes)
1646{
1647 struct drm_framebuffer *fb = fb_helper->fb;
1648
1649 drm_fb_helper_fill_fix(info, pitch: fb->pitches[0],
1650 is_color_indexed: fb->format->is_color_indexed);
1651 drm_fb_helper_fill_var(info, fb_helper,
1652 fb_width: sizes->fb_width, fb_height: sizes->fb_height);
1653
1654 info->par = fb_helper;
1655 /*
1656 * The DRM drivers fbdev emulation device name can be confusing if the
1657 * driver name also has a "drm" suffix on it. Leading to names such as
1658 * "simpledrmdrmfb" in /proc/fb. Unfortunately, it's an uAPI and can't
1659 * be changed due user-space tools (e.g: pm-utils) matching against it.
1660 */
1661 snprintf(buf: info->fix.id, size: sizeof(info->fix.id), fmt: "%sdrmfb",
1662 fb_helper->dev->driver->name);
1663
1664}
1665EXPORT_SYMBOL(drm_fb_helper_fill_info);
1666
1667/*
1668 * This is a continuation of drm_setup_crtcs() that sets up anything related
1669 * to the framebuffer. During initialization, drm_setup_crtcs() is called before
1670 * the framebuffer has been allocated (fb_helper->fb and fb_helper->info).
1671 * So, any setup that touches those fields needs to be done here instead of in
1672 * drm_setup_crtcs().
1673 */
1674static void drm_setup_crtcs_fb(struct drm_fb_helper *fb_helper)
1675{
1676 struct drm_client_dev *client = &fb_helper->client;
1677 struct drm_connector_list_iter conn_iter;
1678 struct fb_info *info = fb_helper->info;
1679 unsigned int rotation, sw_rotations = 0;
1680 struct drm_connector *connector;
1681 struct drm_mode_set *modeset;
1682
1683 mutex_lock(&client->modeset_mutex);
1684 drm_client_for_each_modeset(modeset, client) {
1685 if (!modeset->num_connectors)
1686 continue;
1687
1688 modeset->fb = fb_helper->fb;
1689
1690 if (drm_client_rotation(modeset, rotation: &rotation))
1691 /* Rotating in hardware, fbcon should not rotate */
1692 sw_rotations |= DRM_MODE_ROTATE_0;
1693 else
1694 sw_rotations |= rotation;
1695 }
1696 mutex_unlock(lock: &client->modeset_mutex);
1697
1698 drm_connector_list_iter_begin(dev: fb_helper->dev, iter: &conn_iter);
1699 drm_client_for_each_connector_iter(connector, &conn_iter) {
1700
1701 /* use first connected connector for the physical dimensions */
1702 if (connector->status == connector_status_connected) {
1703 info->var.width = connector->display_info.width_mm;
1704 info->var.height = connector->display_info.height_mm;
1705 break;
1706 }
1707 }
1708 drm_connector_list_iter_end(iter: &conn_iter);
1709
1710 switch (sw_rotations) {
1711 case DRM_MODE_ROTATE_0:
1712 info->fbcon_rotate_hint = FB_ROTATE_UR;
1713 break;
1714 case DRM_MODE_ROTATE_90:
1715 info->fbcon_rotate_hint = FB_ROTATE_CCW;
1716 break;
1717 case DRM_MODE_ROTATE_180:
1718 info->fbcon_rotate_hint = FB_ROTATE_UD;
1719 break;
1720 case DRM_MODE_ROTATE_270:
1721 info->fbcon_rotate_hint = FB_ROTATE_CW;
1722 break;
1723 default:
1724 /*
1725 * Multiple bits are set / multiple rotations requested
1726 * fbcon cannot handle separate rotation settings per
1727 * output, so fallback to unrotated.
1728 */
1729 info->fbcon_rotate_hint = FB_ROTATE_UR;
1730 }
1731}
1732
1733/* Note: Drops fb_helper->lock before returning. */
1734static int
1735__drm_fb_helper_initial_config_and_unlock(struct drm_fb_helper *fb_helper)
1736{
1737 struct drm_device *dev = fb_helper->dev;
1738 struct fb_info *info;
1739 unsigned int width, height;
1740 int ret;
1741
1742 width = dev->mode_config.max_width;
1743 height = dev->mode_config.max_height;
1744
1745 drm_client_modeset_probe(client: &fb_helper->client, width, height);
1746
1747 info = drm_fb_helper_alloc_info(fb_helper);
1748 if (IS_ERR(ptr: info))
1749 return PTR_ERR(ptr: info);
1750
1751 ret = drm_fb_helper_single_fb_probe(fb_helper);
1752 if (ret < 0) {
1753 if (ret == -EAGAIN) {
1754 fb_helper->deferred_setup = true;
1755 ret = 0;
1756 }
1757 mutex_unlock(lock: &fb_helper->lock);
1758
1759 goto err_drm_fb_helper_release_info;
1760 }
1761 drm_setup_crtcs_fb(fb_helper);
1762
1763 fb_helper->deferred_setup = false;
1764
1765 info->var.pixclock = 0;
1766
1767 /* Need to drop locks to avoid recursive deadlock in
1768 * register_framebuffer. This is ok because the only thing left to do is
1769 * register the fbdev emulation instance in kernel_fb_helper_list. */
1770 mutex_unlock(lock: &fb_helper->lock);
1771
1772 ret = register_framebuffer(fb_info: info);
1773 if (ret < 0)
1774 return ret;
1775
1776 drm_info(dev, "fb%d: %s frame buffer device\n",
1777 info->node, info->fix.id);
1778
1779 mutex_lock(&kernel_fb_helper_lock);
1780 list_add(new: &fb_helper->kernel_fb_list, head: &kernel_fb_helper_list);
1781 mutex_unlock(lock: &kernel_fb_helper_lock);
1782
1783 return 0;
1784
1785err_drm_fb_helper_release_info:
1786 drm_fb_helper_release_info(fb_helper);
1787 return ret;
1788}
1789
1790/**
1791 * drm_fb_helper_initial_config - setup a sane initial connector configuration
1792 * @fb_helper: fb_helper device struct
1793 *
1794 * Scans the CRTCs and connectors and tries to put together an initial setup.
1795 * At the moment, this is a cloned configuration across all heads with
1796 * a new framebuffer object as the backing store.
1797 *
1798 * Note that this also registers the fbdev and so allows userspace to call into
1799 * the driver through the fbdev interfaces.
1800 *
1801 * This function will call down into the &drm_driver.fbdev_probe callback
1802 * to let the driver allocate and initialize the fbdev info structure and the
1803 * drm framebuffer used to back the fbdev. drm_fb_helper_fill_info() is provided
1804 * as a helper to setup simple default values for the fbdev info structure.
1805 *
1806 * HANG DEBUGGING:
1807 *
1808 * When you have fbcon support built-in or already loaded, this function will do
1809 * a full modeset to setup the fbdev console. Due to locking misdesign in the
1810 * VT/fbdev subsystem that entire modeset sequence has to be done while holding
1811 * console_lock. Until console_unlock is called no dmesg lines will be sent out
1812 * to consoles, not even serial console. This means when your driver crashes,
1813 * you will see absolutely nothing else but a system stuck in this function,
1814 * with no further output. Any kind of printk() you place within your own driver
1815 * or in the drm core modeset code will also never show up.
1816 *
1817 * Standard debug practice is to run the fbcon setup without taking the
1818 * console_lock as a hack, to be able to see backtraces and crashes on the
1819 * serial line. This can be done by setting the fb.lockless_register_fb=1 kernel
1820 * cmdline option.
1821 *
1822 * The other option is to just disable fbdev emulation since very likely the
1823 * first modeset from userspace will crash in the same way, and is even easier
1824 * to debug. This can be done by setting the drm_kms_helper.fbdev_emulation=0
1825 * kernel cmdline option.
1826 *
1827 * RETURNS:
1828 * Zero if everything went ok, nonzero otherwise.
1829 */
1830int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper)
1831{
1832 int ret;
1833
1834 if (!drm_fbdev_emulation)
1835 return 0;
1836
1837 mutex_lock(&fb_helper->lock);
1838 ret = __drm_fb_helper_initial_config_and_unlock(fb_helper);
1839
1840 return ret;
1841}
1842EXPORT_SYMBOL(drm_fb_helper_initial_config);
1843
1844/**
1845 * drm_fb_helper_hotplug_event - respond to a hotplug notification by
1846 * probing all the outputs attached to the fb
1847 * @fb_helper: driver-allocated fbdev helper, can be NULL
1848 *
1849 * Scan the connectors attached to the fb_helper and try to put together a
1850 * setup after notification of a change in output configuration.
1851 *
1852 * Called at runtime, takes the mode config locks to be able to check/change the
1853 * modeset configuration. Must be run from process context (which usually means
1854 * either the output polling work or a work item launched from the driver's
1855 * hotplug interrupt).
1856 *
1857 * Note that drivers may call this even before calling
1858 * drm_fb_helper_initial_config but only after drm_fb_helper_init. This allows
1859 * for a race-free fbcon setup and will make sure that the fbdev emulation will
1860 * not miss any hotplug events.
1861 *
1862 * RETURNS:
1863 * 0 on success and a non-zero error code otherwise.
1864 */
1865int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
1866{
1867 int err = 0;
1868
1869 if (!drm_fbdev_emulation || !fb_helper)
1870 return 0;
1871
1872 mutex_lock(&fb_helper->lock);
1873 if (fb_helper->deferred_setup) {
1874 err = __drm_fb_helper_initial_config_and_unlock(fb_helper);
1875 return err;
1876 }
1877
1878 if (!fb_helper->fb || !drm_master_internal_acquire(dev: fb_helper->dev)) {
1879 fb_helper->delayed_hotplug = true;
1880 mutex_unlock(lock: &fb_helper->lock);
1881 return err;
1882 }
1883
1884 drm_master_internal_release(dev: fb_helper->dev);
1885
1886 drm_dbg_kms(fb_helper->dev, "\n");
1887
1888 drm_client_modeset_probe(client: &fb_helper->client, width: fb_helper->fb->width, height: fb_helper->fb->height);
1889 drm_setup_crtcs_fb(fb_helper);
1890 mutex_unlock(lock: &fb_helper->lock);
1891
1892 drm_fb_helper_set_par(fb_helper->info);
1893
1894 return 0;
1895}
1896EXPORT_SYMBOL(drm_fb_helper_hotplug_event);
1897

source code of linux/drivers/gpu/drm/drm_fb_helper.c