2 * Copyright (c) 2006-2009 Red Hat Inc.
3 * Copyright (c) 2006-2008 Intel Corporation
4 * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
6 * DRM framebuffer helper functions
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.
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
27 * Dave Airlie <airlied@linux.ie>
28 * Jesse Barnes <jesse.barnes@intel.com>
30 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
32 #include <linux/console.h>
33 #include <linux/sysrq.h>
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>
44 #include "drm_internal.h"
46 static bool drm_fbdev_emulation = true;
47 module_param_named(fbdev_emulation, drm_fbdev_emulation, bool, 0600);
48 MODULE_PARM_DESC(fbdev_emulation,
49 "Enable legacy fbdev emulation [default=true]");
51 static int drm_fbdev_overalloc = CONFIG_DRM_FBDEV_OVERALLOC;
52 module_param(drm_fbdev_overalloc, int, 0444);
53 MODULE_PARM_DESC(drm_fbdev_overalloc,
54 "Overallocation of the fbdev buffer (%) [default="
55 __MODULE_STRING(CONFIG_DRM_FBDEV_OVERALLOC) "]");
58 * In order to keep user-space compatibility, we want in certain use-cases
59 * to keep leaking the fbdev physical address to the user-space program
60 * handling the fbdev buffer.
61 * This is a bad habit essentially kept into closed source opengl driver
62 * that should really be moved into open-source upstream projects instead
63 * of using legacy physical addresses in user space to communicate with
64 * other out-of-tree kernel modules.
66 * This module_param *should* be removed as soon as possible and be
67 * considered as a broken and legacy behaviour from a modern fbdev device.
69 #if IS_ENABLED(CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM)
70 static bool drm_leak_fbdev_smem;
71 module_param_unsafe(drm_leak_fbdev_smem, bool, 0600);
72 MODULE_PARM_DESC(drm_leak_fbdev_smem,
73 "Allow unsafe leaking fbdev physical smem address [default=false]");
76 static LIST_HEAD(kernel_fb_helper_list);
77 static DEFINE_MUTEX(kernel_fb_helper_lock);
82 * The fb helper functions are useful to provide an fbdev on top of a drm kernel
83 * mode setting driver. They can be used mostly independently from the crtc
84 * helper functions used by many drivers to implement the kernel mode setting
87 * Drivers that support a dumb buffer with a virtual address and mmap support,
88 * should try out the generic fbdev emulation using drm_fbdev_generic_setup().
89 * It will automatically set up deferred I/O if the driver requires a shadow
92 * Existing fbdev implementations should restore the fbdev console by using
93 * drm_fb_helper_lastclose() as their &drm_driver.lastclose callback.
94 * They should also notify the fb helper code from updates to the output
95 * configuration by using drm_fb_helper_output_poll_changed() as their
96 * &drm_mode_config_funcs.output_poll_changed callback. New implementations
97 * of fbdev should be build on top of struct &drm_client_funcs, which handles
98 * this automatically. Setting the old callbacks should be avoided.
100 * For suspend/resume consider using drm_mode_config_helper_suspend() and
101 * drm_mode_config_helper_resume() which takes care of fbdev as well.
103 * All other functions exported by the fb helper library can be used to
104 * implement the fbdev driver interface by the driver.
106 * It is possible, though perhaps somewhat tricky, to implement race-free
107 * hotplug detection using the fbdev helpers. The drm_fb_helper_prepare()
108 * helper must be called first to initialize the minimum required to make
109 * hotplug detection work. Drivers also need to make sure to properly set up
110 * the &drm_mode_config.funcs member. After calling drm_kms_helper_poll_init()
111 * it is safe to enable interrupts and start processing hotplug events. At the
112 * same time, drivers should initialize all modeset objects such as CRTCs,
113 * encoders and connectors. To finish up the fbdev helper initialization, the
114 * drm_fb_helper_init() function is called. To probe for all attached displays
115 * and set up an initial configuration using the detected hardware, drivers
116 * should call drm_fb_helper_initial_config().
118 * If &drm_framebuffer_funcs.dirty is set, the
119 * drm_fb_helper_{cfb,sys}_{write,fillrect,copyarea,imageblit} functions will
120 * accumulate changes and schedule &drm_fb_helper.dirty_work to run right
121 * away. This worker then calls the dirty() function ensuring that it will
122 * always run in process context since the fb_*() function could be running in
123 * atomic context. If drm_fb_helper_deferred_io() is used as the deferred_io
124 * callback it will also schedule dirty_work with the damage collected from the
127 * Deferred I/O is not compatible with SHMEM. Such drivers should request an
128 * fbdev shadow buffer and call drm_fbdev_generic_setup() instead.
131 static void drm_fb_helper_restore_lut_atomic(struct drm_crtc *crtc)
133 uint16_t *r_base, *g_base, *b_base;
135 if (crtc->funcs->gamma_set == NULL)
138 r_base = crtc->gamma_store;
139 g_base = r_base + crtc->gamma_size;
140 b_base = g_base + crtc->gamma_size;
142 crtc->funcs->gamma_set(crtc, r_base, g_base, b_base,
143 crtc->gamma_size, NULL);
147 * drm_fb_helper_debug_enter - implementation for &fb_ops.fb_debug_enter
148 * @info: fbdev registered by the helper
150 int drm_fb_helper_debug_enter(struct fb_info *info)
152 struct drm_fb_helper *helper = info->par;
153 const struct drm_crtc_helper_funcs *funcs;
154 struct drm_mode_set *mode_set;
156 list_for_each_entry(helper, &kernel_fb_helper_list, kernel_fb_list) {
157 mutex_lock(&helper->client.modeset_mutex);
158 drm_client_for_each_modeset(mode_set, &helper->client) {
159 if (!mode_set->crtc->enabled)
162 funcs = mode_set->crtc->helper_private;
163 if (funcs->mode_set_base_atomic == NULL)
166 if (drm_drv_uses_atomic_modeset(mode_set->crtc->dev))
169 funcs->mode_set_base_atomic(mode_set->crtc,
173 ENTER_ATOMIC_MODE_SET);
175 mutex_unlock(&helper->client.modeset_mutex);
180 EXPORT_SYMBOL(drm_fb_helper_debug_enter);
183 * drm_fb_helper_debug_leave - implementation for &fb_ops.fb_debug_leave
184 * @info: fbdev registered by the helper
186 int drm_fb_helper_debug_leave(struct fb_info *info)
188 struct drm_fb_helper *helper = info->par;
189 struct drm_client_dev *client = &helper->client;
190 struct drm_device *dev = helper->dev;
191 struct drm_crtc *crtc;
192 const struct drm_crtc_helper_funcs *funcs;
193 struct drm_mode_set *mode_set;
194 struct drm_framebuffer *fb;
196 mutex_lock(&client->modeset_mutex);
197 drm_client_for_each_modeset(mode_set, client) {
198 crtc = mode_set->crtc;
199 if (drm_drv_uses_atomic_modeset(crtc->dev))
202 funcs = crtc->helper_private;
203 fb = crtc->primary->fb;
209 drm_err(dev, "no fb to restore?\n");
213 if (funcs->mode_set_base_atomic == NULL)
216 drm_fb_helper_restore_lut_atomic(mode_set->crtc);
217 funcs->mode_set_base_atomic(mode_set->crtc, fb, crtc->x,
218 crtc->y, LEAVE_ATOMIC_MODE_SET);
220 mutex_unlock(&client->modeset_mutex);
224 EXPORT_SYMBOL(drm_fb_helper_debug_leave);
227 __drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper,
233 if (!drm_fbdev_emulation || !fb_helper)
236 if (READ_ONCE(fb_helper->deferred_setup))
239 mutex_lock(&fb_helper->lock);
242 * Yes this is the _locked version which expects the master lock
243 * to be held. But for forced restores we're intentionally
244 * racing here, see drm_fb_helper_set_par().
246 ret = drm_client_modeset_commit_locked(&fb_helper->client);
248 ret = drm_client_modeset_commit(&fb_helper->client);
251 do_delayed = fb_helper->delayed_hotplug;
253 fb_helper->delayed_hotplug = false;
254 mutex_unlock(&fb_helper->lock);
257 drm_fb_helper_hotplug_event(fb_helper);
263 * drm_fb_helper_restore_fbdev_mode_unlocked - restore fbdev configuration
264 * @fb_helper: driver-allocated fbdev helper, can be NULL
266 * This should be called from driver's drm &drm_driver.lastclose callback
267 * when implementing an fbcon on top of kms using this helper. This ensures that
268 * the user isn't greeted with a black screen when e.g. X dies.
271 * Zero if everything went ok, negative error code otherwise.
273 int drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper)
275 return __drm_fb_helper_restore_fbdev_mode_unlocked(fb_helper, false);
277 EXPORT_SYMBOL(drm_fb_helper_restore_fbdev_mode_unlocked);
279 #ifdef CONFIG_MAGIC_SYSRQ
280 /* emergency restore, don't bother with error reporting */
281 static void drm_fb_helper_restore_work_fn(struct work_struct *ignored)
283 struct drm_fb_helper *helper;
285 mutex_lock(&kernel_fb_helper_lock);
286 list_for_each_entry(helper, &kernel_fb_helper_list, kernel_fb_list) {
287 struct drm_device *dev = helper->dev;
289 if (dev->switch_power_state == DRM_SWITCH_POWER_OFF)
292 mutex_lock(&helper->lock);
293 drm_client_modeset_commit_locked(&helper->client);
294 mutex_unlock(&helper->lock);
296 mutex_unlock(&kernel_fb_helper_lock);
299 static DECLARE_WORK(drm_fb_helper_restore_work, drm_fb_helper_restore_work_fn);
301 static void drm_fb_helper_sysrq(int dummy1)
303 schedule_work(&drm_fb_helper_restore_work);
306 static const struct sysrq_key_op sysrq_drm_fb_helper_restore_op = {
307 .handler = drm_fb_helper_sysrq,
308 .help_msg = "force-fb(v)",
309 .action_msg = "Restore framebuffer console",
312 static const struct sysrq_key_op sysrq_drm_fb_helper_restore_op = { };
315 static void drm_fb_helper_dpms(struct fb_info *info, int dpms_mode)
317 struct drm_fb_helper *fb_helper = info->par;
319 mutex_lock(&fb_helper->lock);
320 drm_client_modeset_dpms(&fb_helper->client, dpms_mode);
321 mutex_unlock(&fb_helper->lock);
325 * drm_fb_helper_blank - implementation for &fb_ops.fb_blank
326 * @blank: desired blanking state
327 * @info: fbdev registered by the helper
329 int drm_fb_helper_blank(int blank, struct fb_info *info)
331 if (oops_in_progress)
335 /* Display: On; HSync: On, VSync: On */
336 case FB_BLANK_UNBLANK:
337 drm_fb_helper_dpms(info, DRM_MODE_DPMS_ON);
339 /* Display: Off; HSync: On, VSync: On */
340 case FB_BLANK_NORMAL:
341 drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY);
343 /* Display: Off; HSync: Off, VSync: On */
344 case FB_BLANK_HSYNC_SUSPEND:
345 drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY);
347 /* Display: Off; HSync: On, VSync: Off */
348 case FB_BLANK_VSYNC_SUSPEND:
349 drm_fb_helper_dpms(info, DRM_MODE_DPMS_SUSPEND);
351 /* Display: Off; HSync: Off, VSync: Off */
352 case FB_BLANK_POWERDOWN:
353 drm_fb_helper_dpms(info, DRM_MODE_DPMS_OFF);
358 EXPORT_SYMBOL(drm_fb_helper_blank);
360 static void drm_fb_helper_resume_worker(struct work_struct *work)
362 struct drm_fb_helper *helper = container_of(work, struct drm_fb_helper,
366 fb_set_suspend(helper->info, 0);
370 static void drm_fb_helper_fb_dirty(struct drm_fb_helper *helper)
372 struct drm_device *dev = helper->dev;
373 struct drm_clip_rect *clip = &helper->damage_clip;
374 struct drm_clip_rect clip_copy;
378 if (drm_WARN_ON_ONCE(dev, !helper->funcs->fb_dirty))
381 spin_lock_irqsave(&helper->damage_lock, flags);
383 clip->x1 = clip->y1 = ~0;
384 clip->x2 = clip->y2 = 0;
385 spin_unlock_irqrestore(&helper->damage_lock, flags);
387 ret = helper->funcs->fb_dirty(helper, &clip_copy);
395 * Restore damage clip rectangle on errors. The next run
396 * of the damage worker will perform the update.
398 spin_lock_irqsave(&helper->damage_lock, flags);
399 clip->x1 = min_t(u32, clip->x1, clip_copy.x1);
400 clip->y1 = min_t(u32, clip->y1, clip_copy.y1);
401 clip->x2 = max_t(u32, clip->x2, clip_copy.x2);
402 clip->y2 = max_t(u32, clip->y2, clip_copy.y2);
403 spin_unlock_irqrestore(&helper->damage_lock, flags);
406 static void drm_fb_helper_damage_work(struct work_struct *work)
408 struct drm_fb_helper *helper = container_of(work, struct drm_fb_helper, damage_work);
410 drm_fb_helper_fb_dirty(helper);
414 * drm_fb_helper_prepare - setup a drm_fb_helper structure
416 * @helper: driver-allocated fbdev helper structure to set up
417 * @funcs: pointer to structure of functions associate with this helper
419 * Sets up the bare minimum to make the framebuffer helper usable. This is
420 * useful to implement race-free initialization of the polling helpers.
422 void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper,
423 const struct drm_fb_helper_funcs *funcs)
425 INIT_LIST_HEAD(&helper->kernel_fb_list);
426 spin_lock_init(&helper->damage_lock);
427 INIT_WORK(&helper->resume_work, drm_fb_helper_resume_worker);
428 INIT_WORK(&helper->damage_work, drm_fb_helper_damage_work);
429 helper->damage_clip.x1 = helper->damage_clip.y1 = ~0;
430 mutex_init(&helper->lock);
431 helper->funcs = funcs;
434 EXPORT_SYMBOL(drm_fb_helper_prepare);
437 * drm_fb_helper_init - initialize a &struct drm_fb_helper
439 * @fb_helper: driver-allocated fbdev helper structure to initialize
441 * This allocates the structures for the fbdev helper with the given limits.
442 * Note that this won't yet touch the hardware (through the driver interfaces)
443 * nor register the fbdev. This is only done in drm_fb_helper_initial_config()
444 * to allow driver writes more control over the exact init sequence.
446 * Drivers must call drm_fb_helper_prepare() before calling this function.
449 * Zero if everything went ok, nonzero otherwise.
451 int drm_fb_helper_init(struct drm_device *dev,
452 struct drm_fb_helper *fb_helper)
457 * If this is not the generic fbdev client, initialize a drm_client
458 * without callbacks so we can use the modesets.
460 if (!fb_helper->client.funcs) {
461 ret = drm_client_init(dev, &fb_helper->client, "drm_fb_helper", NULL);
466 dev->fb_helper = fb_helper;
470 EXPORT_SYMBOL(drm_fb_helper_init);
473 * drm_fb_helper_alloc_info - allocate fb_info and some of its members
474 * @fb_helper: driver-allocated fbdev helper
476 * A helper to alloc fb_info and the members cmap and apertures. Called
477 * by the driver within the fb_probe fb_helper callback function. Drivers do not
478 * need to release the allocated fb_info structure themselves, this is
479 * automatically done when calling drm_fb_helper_fini().
482 * fb_info pointer if things went okay, pointer containing error code
485 struct fb_info *drm_fb_helper_alloc_info(struct drm_fb_helper *fb_helper)
487 struct device *dev = fb_helper->dev->dev;
488 struct fb_info *info;
491 info = framebuffer_alloc(0, dev);
493 return ERR_PTR(-ENOMEM);
495 ret = fb_alloc_cmap(&info->cmap, 256, 0);
500 * TODO: We really should be smarter here and alloc an aperture
501 * for each IORESOURCE_MEM resource helper->dev->dev has and also
502 * init the ranges of the appertures based on the resources.
503 * Note some drivers currently count on there being only 1 empty
504 * aperture and fill this themselves, these will need to be dealt
505 * with somehow when fixing this.
507 info->apertures = alloc_apertures(1);
508 if (!info->apertures) {
513 fb_helper->info = info;
514 info->skip_vt_switch = true;
519 fb_dealloc_cmap(&info->cmap);
521 framebuffer_release(info);
524 EXPORT_SYMBOL(drm_fb_helper_alloc_info);
527 * drm_fb_helper_unregister_info - unregister fb_info framebuffer device
528 * @fb_helper: driver-allocated fbdev helper, can be NULL
530 * A wrapper around unregister_framebuffer, to release the fb_info
531 * framebuffer device. This must be called before releasing all resources for
532 * @fb_helper by calling drm_fb_helper_fini().
534 void drm_fb_helper_unregister_info(struct drm_fb_helper *fb_helper)
536 if (fb_helper && fb_helper->info)
537 unregister_framebuffer(fb_helper->info);
539 EXPORT_SYMBOL(drm_fb_helper_unregister_info);
542 * drm_fb_helper_fini - finialize a &struct drm_fb_helper
543 * @fb_helper: driver-allocated fbdev helper, can be NULL
545 * This cleans up all remaining resources associated with @fb_helper.
547 void drm_fb_helper_fini(struct drm_fb_helper *fb_helper)
549 struct fb_info *info;
554 fb_helper->dev->fb_helper = NULL;
556 if (!drm_fbdev_emulation)
559 cancel_work_sync(&fb_helper->resume_work);
560 cancel_work_sync(&fb_helper->damage_work);
562 info = fb_helper->info;
565 fb_dealloc_cmap(&info->cmap);
566 framebuffer_release(info);
568 fb_helper->info = NULL;
570 mutex_lock(&kernel_fb_helper_lock);
571 if (!list_empty(&fb_helper->kernel_fb_list)) {
572 list_del(&fb_helper->kernel_fb_list);
573 if (list_empty(&kernel_fb_helper_list))
574 unregister_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
576 mutex_unlock(&kernel_fb_helper_lock);
578 mutex_destroy(&fb_helper->lock);
580 if (!fb_helper->client.funcs)
581 drm_client_release(&fb_helper->client);
583 EXPORT_SYMBOL(drm_fb_helper_fini);
585 static void drm_fb_helper_add_damage_clip(struct drm_fb_helper *helper, u32 x, u32 y,
586 u32 width, u32 height)
588 struct drm_clip_rect *clip = &helper->damage_clip;
591 spin_lock_irqsave(&helper->damage_lock, flags);
592 clip->x1 = min_t(u32, clip->x1, x);
593 clip->y1 = min_t(u32, clip->y1, y);
594 clip->x2 = max_t(u32, clip->x2, x + width);
595 clip->y2 = max_t(u32, clip->y2, y + height);
596 spin_unlock_irqrestore(&helper->damage_lock, flags);
599 static void drm_fb_helper_damage(struct drm_fb_helper *helper, u32 x, u32 y,
600 u32 width, u32 height)
602 drm_fb_helper_add_damage_clip(helper, x, y, width, height);
604 schedule_work(&helper->damage_work);
608 * Convert memory region into area of scanlines and pixels per
609 * scanline. The parameters off and len must not reach beyond
610 * the end of the framebuffer.
612 static void drm_fb_helper_memory_range_to_clip(struct fb_info *info, off_t off, size_t len,
613 struct drm_rect *clip)
615 off_t end = off + len;
617 u32 y1 = off / info->fix.line_length;
618 u32 x2 = info->var.xres;
619 u32 y2 = DIV_ROUND_UP(end, info->fix.line_length);
621 if ((y2 - y1) == 1) {
623 * We've only written to a single scanline. Try to reduce
624 * the number of horizontal pixels that need an update.
626 off_t bit_off = (off % info->fix.line_length) * 8;
627 off_t bit_end = (end % info->fix.line_length) * 8;
629 x1 = bit_off / info->var.bits_per_pixel;
630 x2 = DIV_ROUND_UP(bit_end, info->var.bits_per_pixel);
633 drm_rect_init(clip, x1, y1, x2 - x1, y2 - y1);
637 * drm_fb_helper_deferred_io() - fbdev deferred_io callback function
638 * @info: fb_info struct pointer
639 * @pagereflist: list of mmap framebuffer pages that have to be flushed
641 * This function is used as the &fb_deferred_io.deferred_io
642 * callback function for flushing the fbdev mmap writes.
644 void drm_fb_helper_deferred_io(struct fb_info *info, struct list_head *pagereflist)
646 struct drm_fb_helper *helper = info->par;
647 unsigned long start, end, min_off, max_off;
648 struct fb_deferred_io_pageref *pageref;
649 struct drm_rect damage_area;
653 list_for_each_entry(pageref, pagereflist, list) {
654 start = pageref->offset;
655 end = start + PAGE_SIZE;
656 min_off = min(min_off, start);
657 max_off = max(max_off, end);
661 * As we can only track pages, we might reach beyond the end
662 * of the screen and account for non-existing scanlines. Hence,
663 * keep the covered memory area within the screen buffer.
665 max_off = min(max_off, info->screen_size);
667 if (min_off < max_off) {
668 drm_fb_helper_memory_range_to_clip(info, min_off, max_off - min_off, &damage_area);
669 drm_fb_helper_damage(helper, damage_area.x1, damage_area.y1,
670 drm_rect_width(&damage_area),
671 drm_rect_height(&damage_area));
674 EXPORT_SYMBOL(drm_fb_helper_deferred_io);
676 typedef ssize_t (*drm_fb_helper_read_screen)(struct fb_info *info, char __user *buf,
677 size_t count, loff_t pos);
679 static ssize_t __drm_fb_helper_read(struct fb_info *info, char __user *buf, size_t count,
680 loff_t *ppos, drm_fb_helper_read_screen read_screen)
686 if (info->screen_size)
687 total_size = info->screen_size;
689 total_size = info->fix.smem_len;
691 if (pos >= total_size)
693 if (count >= total_size)
695 if (total_size - count < pos)
696 count = total_size - pos;
698 if (info->fbops->fb_sync)
699 info->fbops->fb_sync(info);
701 ret = read_screen(info, buf, count, pos);
708 typedef ssize_t (*drm_fb_helper_write_screen)(struct fb_info *info, const char __user *buf,
709 size_t count, loff_t pos);
711 static ssize_t __drm_fb_helper_write(struct fb_info *info, const char __user *buf, size_t count,
712 loff_t *ppos, drm_fb_helper_write_screen write_screen)
719 if (info->screen_size)
720 total_size = info->screen_size;
722 total_size = info->fix.smem_len;
724 if (pos > total_size)
726 if (count > total_size) {
730 if (total_size - count < pos) {
733 count = total_size - pos;
736 if (info->fbops->fb_sync)
737 info->fbops->fb_sync(info);
740 * Copy to framebuffer even if we already logged an error. Emulates
741 * the behavior of the original fbdev implementation.
743 ret = write_screen(info, buf, count, pos);
745 return ret; /* return last error, if any */
747 return err; /* return previous error, if any */
754 static ssize_t drm_fb_helper_read_screen_buffer(struct fb_info *info, char __user *buf,
755 size_t count, loff_t pos)
757 const char *src = info->screen_buffer + pos;
759 if (copy_to_user(buf, src, count))
766 * drm_fb_helper_sys_read - Implements struct &fb_ops.fb_read for system memory
767 * @info: fb_info struct pointer
768 * @buf: userspace buffer to read from framebuffer memory
769 * @count: number of bytes to read from framebuffer memory
770 * @ppos: read offset within framebuffer memory
773 * The number of bytes read on success, or an error code otherwise.
775 ssize_t drm_fb_helper_sys_read(struct fb_info *info, char __user *buf,
776 size_t count, loff_t *ppos)
778 return __drm_fb_helper_read(info, buf, count, ppos, drm_fb_helper_read_screen_buffer);
780 EXPORT_SYMBOL(drm_fb_helper_sys_read);
782 static ssize_t drm_fb_helper_write_screen_buffer(struct fb_info *info, const char __user *buf,
783 size_t count, loff_t pos)
785 char *dst = info->screen_buffer + pos;
787 if (copy_from_user(dst, buf, count))
794 * drm_fb_helper_sys_write - Implements struct &fb_ops.fb_write for system memory
795 * @info: fb_info struct pointer
796 * @buf: userspace buffer to write to framebuffer memory
797 * @count: number of bytes to write to framebuffer memory
798 * @ppos: write offset within framebuffer memory
801 * The number of bytes written on success, or an error code otherwise.
803 ssize_t drm_fb_helper_sys_write(struct fb_info *info, const char __user *buf,
804 size_t count, loff_t *ppos)
806 struct drm_fb_helper *helper = info->par;
809 struct drm_rect damage_area;
811 ret = __drm_fb_helper_write(info, buf, count, ppos, drm_fb_helper_write_screen_buffer);
815 if (helper->funcs->fb_dirty) {
816 drm_fb_helper_memory_range_to_clip(info, pos, ret, &damage_area);
817 drm_fb_helper_damage(helper, damage_area.x1, damage_area.y1,
818 drm_rect_width(&damage_area),
819 drm_rect_height(&damage_area));
824 EXPORT_SYMBOL(drm_fb_helper_sys_write);
827 * drm_fb_helper_sys_fillrect - wrapper around sys_fillrect
828 * @info: fbdev registered by the helper
829 * @rect: info about rectangle to fill
831 * A wrapper around sys_fillrect implemented by fbdev core
833 void drm_fb_helper_sys_fillrect(struct fb_info *info,
834 const struct fb_fillrect *rect)
836 struct drm_fb_helper *helper = info->par;
838 sys_fillrect(info, rect);
840 if (helper->funcs->fb_dirty)
841 drm_fb_helper_damage(helper, rect->dx, rect->dy, rect->width, rect->height);
843 EXPORT_SYMBOL(drm_fb_helper_sys_fillrect);
846 * drm_fb_helper_sys_copyarea - wrapper around sys_copyarea
847 * @info: fbdev registered by the helper
848 * @area: info about area to copy
850 * A wrapper around sys_copyarea implemented by fbdev core
852 void drm_fb_helper_sys_copyarea(struct fb_info *info,
853 const struct fb_copyarea *area)
855 struct drm_fb_helper *helper = info->par;
857 sys_copyarea(info, area);
859 if (helper->funcs->fb_dirty)
860 drm_fb_helper_damage(helper, area->dx, area->dy, area->width, area->height);
862 EXPORT_SYMBOL(drm_fb_helper_sys_copyarea);
865 * drm_fb_helper_sys_imageblit - wrapper around sys_imageblit
866 * @info: fbdev registered by the helper
867 * @image: info about image to blit
869 * A wrapper around sys_imageblit implemented by fbdev core
871 void drm_fb_helper_sys_imageblit(struct fb_info *info,
872 const struct fb_image *image)
874 struct drm_fb_helper *helper = info->par;
876 sys_imageblit(info, image);
878 if (helper->funcs->fb_dirty)
879 drm_fb_helper_damage(helper, image->dx, image->dy, image->width, image->height);
881 EXPORT_SYMBOL(drm_fb_helper_sys_imageblit);
883 static ssize_t fb_read_screen_base(struct fb_info *info, char __user *buf, size_t count,
886 const char __iomem *src = info->screen_base + pos;
887 size_t alloc_size = min_t(size_t, count, PAGE_SIZE);
892 tmp = kmalloc(alloc_size, GFP_KERNEL);
897 size_t c = min_t(size_t, count, alloc_size);
899 memcpy_fromio(tmp, src, c);
900 if (copy_to_user(buf, tmp, c)) {
913 return ret ? ret : err;
917 * drm_fb_helper_cfb_read - Implements struct &fb_ops.fb_read for I/O memory
918 * @info: fb_info struct pointer
919 * @buf: userspace buffer to read from framebuffer memory
920 * @count: number of bytes to read from framebuffer memory
921 * @ppos: read offset within framebuffer memory
924 * The number of bytes read on success, or an error code otherwise.
926 ssize_t drm_fb_helper_cfb_read(struct fb_info *info, char __user *buf,
927 size_t count, loff_t *ppos)
929 return __drm_fb_helper_read(info, buf, count, ppos, fb_read_screen_base);
931 EXPORT_SYMBOL(drm_fb_helper_cfb_read);
933 static ssize_t fb_write_screen_base(struct fb_info *info, const char __user *buf, size_t count,
936 char __iomem *dst = info->screen_base + pos;
937 size_t alloc_size = min_t(size_t, count, PAGE_SIZE);
942 tmp = kmalloc(alloc_size, GFP_KERNEL);
947 size_t c = min_t(size_t, count, alloc_size);
949 if (copy_from_user(tmp, buf, c)) {
953 memcpy_toio(dst, tmp, c);
963 return ret ? ret : err;
967 * drm_fb_helper_cfb_write - Implements struct &fb_ops.fb_write for I/O memory
968 * @info: fb_info struct pointer
969 * @buf: userspace buffer to write to framebuffer memory
970 * @count: number of bytes to write to framebuffer memory
971 * @ppos: write offset within framebuffer memory
974 * The number of bytes written on success, or an error code otherwise.
976 ssize_t drm_fb_helper_cfb_write(struct fb_info *info, const char __user *buf,
977 size_t count, loff_t *ppos)
979 struct drm_fb_helper *helper = info->par;
982 struct drm_rect damage_area;
984 ret = __drm_fb_helper_write(info, buf, count, ppos, fb_write_screen_base);
988 if (helper->funcs->fb_dirty) {
989 drm_fb_helper_memory_range_to_clip(info, pos, ret, &damage_area);
990 drm_fb_helper_damage(helper, damage_area.x1, damage_area.y1,
991 drm_rect_width(&damage_area),
992 drm_rect_height(&damage_area));
997 EXPORT_SYMBOL(drm_fb_helper_cfb_write);
1000 * drm_fb_helper_cfb_fillrect - wrapper around cfb_fillrect
1001 * @info: fbdev registered by the helper
1002 * @rect: info about rectangle to fill
1004 * A wrapper around cfb_fillrect implemented by fbdev core
1006 void drm_fb_helper_cfb_fillrect(struct fb_info *info,
1007 const struct fb_fillrect *rect)
1009 struct drm_fb_helper *helper = info->par;
1011 cfb_fillrect(info, rect);
1013 if (helper->funcs->fb_dirty)
1014 drm_fb_helper_damage(helper, rect->dx, rect->dy, rect->width, rect->height);
1016 EXPORT_SYMBOL(drm_fb_helper_cfb_fillrect);
1019 * drm_fb_helper_cfb_copyarea - wrapper around cfb_copyarea
1020 * @info: fbdev registered by the helper
1021 * @area: info about area to copy
1023 * A wrapper around cfb_copyarea implemented by fbdev core
1025 void drm_fb_helper_cfb_copyarea(struct fb_info *info,
1026 const struct fb_copyarea *area)
1028 struct drm_fb_helper *helper = info->par;
1030 cfb_copyarea(info, area);
1032 if (helper->funcs->fb_dirty)
1033 drm_fb_helper_damage(helper, area->dx, area->dy, area->width, area->height);
1035 EXPORT_SYMBOL(drm_fb_helper_cfb_copyarea);
1038 * drm_fb_helper_cfb_imageblit - wrapper around cfb_imageblit
1039 * @info: fbdev registered by the helper
1040 * @image: info about image to blit
1042 * A wrapper around cfb_imageblit implemented by fbdev core
1044 void drm_fb_helper_cfb_imageblit(struct fb_info *info,
1045 const struct fb_image *image)
1047 struct drm_fb_helper *helper = info->par;
1049 cfb_imageblit(info, image);
1051 if (helper->funcs->fb_dirty)
1052 drm_fb_helper_damage(helper, image->dx, image->dy, image->width, image->height);
1054 EXPORT_SYMBOL(drm_fb_helper_cfb_imageblit);
1057 * drm_fb_helper_set_suspend - wrapper around fb_set_suspend
1058 * @fb_helper: driver-allocated fbdev helper, can be NULL
1059 * @suspend: whether to suspend or resume
1061 * A wrapper around fb_set_suspend implemented by fbdev core.
1062 * Use drm_fb_helper_set_suspend_unlocked() if you don't need to take
1065 void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper, bool suspend)
1067 if (fb_helper && fb_helper->info)
1068 fb_set_suspend(fb_helper->info, suspend);
1070 EXPORT_SYMBOL(drm_fb_helper_set_suspend);
1073 * drm_fb_helper_set_suspend_unlocked - wrapper around fb_set_suspend that also
1074 * takes the console lock
1075 * @fb_helper: driver-allocated fbdev helper, can be NULL
1076 * @suspend: whether to suspend or resume
1078 * A wrapper around fb_set_suspend() that takes the console lock. If the lock
1079 * isn't available on resume, a worker is tasked with waiting for the lock
1080 * to become available. The console lock can be pretty contented on resume
1081 * due to all the printk activity.
1083 * This function can be called multiple times with the same state since
1084 * &fb_info.state is checked to see if fbdev is running or not before locking.
1086 * Use drm_fb_helper_set_suspend() if you need to take the lock yourself.
1088 void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper,
1091 if (!fb_helper || !fb_helper->info)
1094 /* make sure there's no pending/ongoing resume */
1095 flush_work(&fb_helper->resume_work);
1098 if (fb_helper->info->state != FBINFO_STATE_RUNNING)
1104 if (fb_helper->info->state == FBINFO_STATE_RUNNING)
1107 if (!console_trylock()) {
1108 schedule_work(&fb_helper->resume_work);
1113 fb_set_suspend(fb_helper->info, suspend);
1116 EXPORT_SYMBOL(drm_fb_helper_set_suspend_unlocked);
1118 static int setcmap_pseudo_palette(struct fb_cmap *cmap, struct fb_info *info)
1120 u32 *palette = (u32 *)info->pseudo_palette;
1123 if (cmap->start + cmap->len > 16)
1126 for (i = 0; i < cmap->len; ++i) {
1127 u16 red = cmap->red[i];
1128 u16 green = cmap->green[i];
1129 u16 blue = cmap->blue[i];
1132 red >>= 16 - info->var.red.length;
1133 green >>= 16 - info->var.green.length;
1134 blue >>= 16 - info->var.blue.length;
1135 value = (red << info->var.red.offset) |
1136 (green << info->var.green.offset) |
1137 (blue << info->var.blue.offset);
1138 if (info->var.transp.length > 0) {
1139 u32 mask = (1 << info->var.transp.length) - 1;
1141 mask <<= info->var.transp.offset;
1144 palette[cmap->start + i] = value;
1150 static int setcmap_legacy(struct fb_cmap *cmap, struct fb_info *info)
1152 struct drm_fb_helper *fb_helper = info->par;
1153 struct drm_mode_set *modeset;
1154 struct drm_crtc *crtc;
1158 drm_modeset_lock_all(fb_helper->dev);
1159 drm_client_for_each_modeset(modeset, &fb_helper->client) {
1160 crtc = modeset->crtc;
1161 if (!crtc->funcs->gamma_set || !crtc->gamma_size) {
1166 if (cmap->start + cmap->len > crtc->gamma_size) {
1171 r = crtc->gamma_store;
1172 g = r + crtc->gamma_size;
1173 b = g + crtc->gamma_size;
1175 memcpy(r + cmap->start, cmap->red, cmap->len * sizeof(*r));
1176 memcpy(g + cmap->start, cmap->green, cmap->len * sizeof(*g));
1177 memcpy(b + cmap->start, cmap->blue, cmap->len * sizeof(*b));
1179 ret = crtc->funcs->gamma_set(crtc, r, g, b,
1180 crtc->gamma_size, NULL);
1185 drm_modeset_unlock_all(fb_helper->dev);
1190 static struct drm_property_blob *setcmap_new_gamma_lut(struct drm_crtc *crtc,
1191 struct fb_cmap *cmap)
1193 struct drm_device *dev = crtc->dev;
1194 struct drm_property_blob *gamma_lut;
1195 struct drm_color_lut *lut;
1196 int size = crtc->gamma_size;
1199 if (!size || cmap->start + cmap->len > size)
1200 return ERR_PTR(-EINVAL);
1202 gamma_lut = drm_property_create_blob(dev, sizeof(*lut) * size, NULL);
1203 if (IS_ERR(gamma_lut))
1206 lut = gamma_lut->data;
1207 if (cmap->start || cmap->len != size) {
1208 u16 *r = crtc->gamma_store;
1209 u16 *g = r + crtc->gamma_size;
1210 u16 *b = g + crtc->gamma_size;
1212 for (i = 0; i < cmap->start; i++) {
1214 lut[i].green = g[i];
1217 for (i = cmap->start + cmap->len; i < size; i++) {
1219 lut[i].green = g[i];
1224 for (i = 0; i < cmap->len; i++) {
1225 lut[cmap->start + i].red = cmap->red[i];
1226 lut[cmap->start + i].green = cmap->green[i];
1227 lut[cmap->start + i].blue = cmap->blue[i];
1233 static int setcmap_atomic(struct fb_cmap *cmap, struct fb_info *info)
1235 struct drm_fb_helper *fb_helper = info->par;
1236 struct drm_device *dev = fb_helper->dev;
1237 struct drm_property_blob *gamma_lut = NULL;
1238 struct drm_modeset_acquire_ctx ctx;
1239 struct drm_crtc_state *crtc_state;
1240 struct drm_atomic_state *state;
1241 struct drm_mode_set *modeset;
1242 struct drm_crtc *crtc;
1247 drm_modeset_acquire_init(&ctx, 0);
1249 state = drm_atomic_state_alloc(dev);
1255 state->acquire_ctx = &ctx;
1257 drm_client_for_each_modeset(modeset, &fb_helper->client) {
1258 crtc = modeset->crtc;
1261 gamma_lut = setcmap_new_gamma_lut(crtc, cmap);
1262 if (IS_ERR(gamma_lut)) {
1263 ret = PTR_ERR(gamma_lut);
1268 crtc_state = drm_atomic_get_crtc_state(state, crtc);
1269 if (IS_ERR(crtc_state)) {
1270 ret = PTR_ERR(crtc_state);
1275 * FIXME: This always uses gamma_lut. Some HW have only
1276 * degamma_lut, in which case we should reset gamma_lut and set
1277 * degamma_lut. See drm_crtc_legacy_gamma_set().
1279 replaced = drm_property_replace_blob(&crtc_state->degamma_lut,
1281 replaced |= drm_property_replace_blob(&crtc_state->ctm, NULL);
1282 replaced |= drm_property_replace_blob(&crtc_state->gamma_lut,
1284 crtc_state->color_mgmt_changed |= replaced;
1287 ret = drm_atomic_commit(state);
1291 drm_client_for_each_modeset(modeset, &fb_helper->client) {
1292 crtc = modeset->crtc;
1294 r = crtc->gamma_store;
1295 g = r + crtc->gamma_size;
1296 b = g + crtc->gamma_size;
1298 memcpy(r + cmap->start, cmap->red, cmap->len * sizeof(*r));
1299 memcpy(g + cmap->start, cmap->green, cmap->len * sizeof(*g));
1300 memcpy(b + cmap->start, cmap->blue, cmap->len * sizeof(*b));
1304 if (ret == -EDEADLK)
1307 drm_property_blob_put(gamma_lut);
1308 drm_atomic_state_put(state);
1310 drm_modeset_drop_locks(&ctx);
1311 drm_modeset_acquire_fini(&ctx);
1316 drm_atomic_state_clear(state);
1317 drm_modeset_backoff(&ctx);
1322 * drm_fb_helper_setcmap - implementation for &fb_ops.fb_setcmap
1323 * @cmap: cmap to set
1324 * @info: fbdev registered by the helper
1326 int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info)
1328 struct drm_fb_helper *fb_helper = info->par;
1329 struct drm_device *dev = fb_helper->dev;
1332 if (oops_in_progress)
1335 mutex_lock(&fb_helper->lock);
1337 if (!drm_master_internal_acquire(dev)) {
1342 mutex_lock(&fb_helper->client.modeset_mutex);
1343 if (info->fix.visual == FB_VISUAL_TRUECOLOR)
1344 ret = setcmap_pseudo_palette(cmap, info);
1345 else if (drm_drv_uses_atomic_modeset(fb_helper->dev))
1346 ret = setcmap_atomic(cmap, info);
1348 ret = setcmap_legacy(cmap, info);
1349 mutex_unlock(&fb_helper->client.modeset_mutex);
1351 drm_master_internal_release(dev);
1353 mutex_unlock(&fb_helper->lock);
1357 EXPORT_SYMBOL(drm_fb_helper_setcmap);
1360 * drm_fb_helper_ioctl - legacy ioctl implementation
1361 * @info: fbdev registered by the helper
1362 * @cmd: ioctl command
1363 * @arg: ioctl argument
1365 * A helper to implement the standard fbdev ioctl. Only
1366 * FBIO_WAITFORVSYNC is implemented for now.
1368 int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd,
1371 struct drm_fb_helper *fb_helper = info->par;
1372 struct drm_device *dev = fb_helper->dev;
1373 struct drm_crtc *crtc;
1376 mutex_lock(&fb_helper->lock);
1377 if (!drm_master_internal_acquire(dev)) {
1383 case FBIO_WAITFORVSYNC:
1385 * Only consider the first CRTC.
1387 * This ioctl is supposed to take the CRTC number as
1388 * an argument, but in fbdev times, what that number
1389 * was supposed to be was quite unclear, different
1390 * drivers were passing that argument differently
1391 * (some by reference, some by value), and most of the
1392 * userspace applications were just hardcoding 0 as an
1395 * The first CRTC should be the integrated panel on
1396 * most drivers, so this is the best choice we can
1397 * make. If we're not smart enough here, one should
1398 * just consider switch the userspace to KMS.
1400 crtc = fb_helper->client.modesets[0].crtc;
1403 * Only wait for a vblank event if the CRTC is
1404 * enabled, otherwise just don't do anythintg,
1405 * not even report an error.
1407 ret = drm_crtc_vblank_get(crtc);
1409 drm_crtc_wait_one_vblank(crtc);
1410 drm_crtc_vblank_put(crtc);
1419 drm_master_internal_release(dev);
1421 mutex_unlock(&fb_helper->lock);
1424 EXPORT_SYMBOL(drm_fb_helper_ioctl);
1426 static bool drm_fb_pixel_format_equal(const struct fb_var_screeninfo *var_1,
1427 const struct fb_var_screeninfo *var_2)
1429 return var_1->bits_per_pixel == var_2->bits_per_pixel &&
1430 var_1->grayscale == var_2->grayscale &&
1431 var_1->red.offset == var_2->red.offset &&
1432 var_1->red.length == var_2->red.length &&
1433 var_1->red.msb_right == var_2->red.msb_right &&
1434 var_1->green.offset == var_2->green.offset &&
1435 var_1->green.length == var_2->green.length &&
1436 var_1->green.msb_right == var_2->green.msb_right &&
1437 var_1->blue.offset == var_2->blue.offset &&
1438 var_1->blue.length == var_2->blue.length &&
1439 var_1->blue.msb_right == var_2->blue.msb_right &&
1440 var_1->transp.offset == var_2->transp.offset &&
1441 var_1->transp.length == var_2->transp.length &&
1442 var_1->transp.msb_right == var_2->transp.msb_right;
1445 static void drm_fb_helper_fill_pixel_fmt(struct fb_var_screeninfo *var,
1446 const struct drm_format_info *format)
1448 u8 depth = format->depth;
1450 if (format->is_color_indexed) {
1451 var->red.offset = 0;
1452 var->green.offset = 0;
1453 var->blue.offset = 0;
1454 var->red.length = depth;
1455 var->green.length = depth;
1456 var->blue.length = depth;
1457 var->transp.offset = 0;
1458 var->transp.length = 0;
1464 var->red.offset = 10;
1465 var->green.offset = 5;
1466 var->blue.offset = 0;
1467 var->red.length = 5;
1468 var->green.length = 5;
1469 var->blue.length = 5;
1470 var->transp.offset = 15;
1471 var->transp.length = 1;
1474 var->red.offset = 11;
1475 var->green.offset = 5;
1476 var->blue.offset = 0;
1477 var->red.length = 5;
1478 var->green.length = 6;
1479 var->blue.length = 5;
1480 var->transp.offset = 0;
1483 var->red.offset = 16;
1484 var->green.offset = 8;
1485 var->blue.offset = 0;
1486 var->red.length = 8;
1487 var->green.length = 8;
1488 var->blue.length = 8;
1489 var->transp.offset = 0;
1490 var->transp.length = 0;
1493 var->red.offset = 16;
1494 var->green.offset = 8;
1495 var->blue.offset = 0;
1496 var->red.length = 8;
1497 var->green.length = 8;
1498 var->blue.length = 8;
1499 var->transp.offset = 24;
1500 var->transp.length = 8;
1508 * drm_fb_helper_check_var - implementation for &fb_ops.fb_check_var
1509 * @var: screeninfo to check
1510 * @info: fbdev registered by the helper
1512 int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
1513 struct fb_info *info)
1515 struct drm_fb_helper *fb_helper = info->par;
1516 struct drm_framebuffer *fb = fb_helper->fb;
1517 const struct drm_format_info *format = fb->format;
1518 struct drm_device *dev = fb_helper->dev;
1521 if (in_dbg_master())
1524 if (var->pixclock != 0) {
1525 drm_dbg_kms(dev, "fbdev emulation doesn't support changing the pixel clock, value of pixclock is ignored\n");
1529 switch (format->format) {
1533 /* supported format with sub-byte pixels */
1537 if ((drm_format_info_block_width(format, 0) > 1) ||
1538 (drm_format_info_block_height(format, 0) > 1))
1544 * Changes struct fb_var_screeninfo are currently not pushed back
1545 * to KMS, hence fail if different settings are requested.
1547 bpp = drm_format_info_bpp(format, 0);
1548 if (var->bits_per_pixel > bpp ||
1549 var->xres > fb->width || var->yres > fb->height ||
1550 var->xres_virtual > fb->width || var->yres_virtual > fb->height) {
1551 drm_dbg_kms(dev, "fb requested width/height/bpp can't fit in current fb "
1552 "request %dx%d-%d (virtual %dx%d) > %dx%d-%d\n",
1553 var->xres, var->yres, var->bits_per_pixel,
1554 var->xres_virtual, var->yres_virtual,
1555 fb->width, fb->height, bpp);
1560 * Workaround for SDL 1.2, which is known to be setting all pixel format
1561 * fields values to zero in some cases. We treat this situation as a
1562 * kind of "use some reasonable autodetected values".
1564 if (!var->red.offset && !var->green.offset &&
1565 !var->blue.offset && !var->transp.offset &&
1566 !var->red.length && !var->green.length &&
1567 !var->blue.length && !var->transp.length &&
1568 !var->red.msb_right && !var->green.msb_right &&
1569 !var->blue.msb_right && !var->transp.msb_right) {
1570 drm_fb_helper_fill_pixel_fmt(var, format);
1574 * Likewise, bits_per_pixel should be rounded up to a supported value.
1576 var->bits_per_pixel = bpp;
1579 * drm fbdev emulation doesn't support changing the pixel format at all,
1580 * so reject all pixel format changing requests.
1582 if (!drm_fb_pixel_format_equal(var, &info->var)) {
1583 drm_dbg_kms(dev, "fbdev emulation doesn't support changing the pixel format\n");
1589 EXPORT_SYMBOL(drm_fb_helper_check_var);
1592 * drm_fb_helper_set_par - implementation for &fb_ops.fb_set_par
1593 * @info: fbdev registered by the helper
1595 * This will let fbcon do the mode init and is called at initialization time by
1596 * the fbdev core when registering the driver, and later on through the hotplug
1599 int drm_fb_helper_set_par(struct fb_info *info)
1601 struct drm_fb_helper *fb_helper = info->par;
1602 struct fb_var_screeninfo *var = &info->var;
1605 if (oops_in_progress)
1608 if (var->pixclock != 0) {
1609 drm_err(fb_helper->dev, "PIXEL CLOCK SET\n");
1614 * Normally we want to make sure that a kms master takes precedence over
1615 * fbdev, to avoid fbdev flickering and occasionally stealing the
1616 * display status. But Xorg first sets the vt back to text mode using
1617 * the KDSET IOCTL with KD_TEXT, and only after that drops the master
1618 * status when exiting.
1620 * In the past this was caught by drm_fb_helper_lastclose(), but on
1621 * modern systems where logind always keeps a drm fd open to orchestrate
1622 * the vt switching, this doesn't work.
1624 * To not break the userspace ABI we have this special case here, which
1625 * is only used for the above case. Everything else uses the normal
1626 * commit function, which ensures that we never steal the display from
1627 * an active drm master.
1629 force = var->activate & FB_ACTIVATE_KD_TEXT;
1631 __drm_fb_helper_restore_fbdev_mode_unlocked(fb_helper, force);
1635 EXPORT_SYMBOL(drm_fb_helper_set_par);
1637 static void pan_set(struct drm_fb_helper *fb_helper, int x, int y)
1639 struct drm_mode_set *mode_set;
1641 mutex_lock(&fb_helper->client.modeset_mutex);
1642 drm_client_for_each_modeset(mode_set, &fb_helper->client) {
1646 mutex_unlock(&fb_helper->client.modeset_mutex);
1649 static int pan_display_atomic(struct fb_var_screeninfo *var,
1650 struct fb_info *info)
1652 struct drm_fb_helper *fb_helper = info->par;
1655 pan_set(fb_helper, var->xoffset, var->yoffset);
1657 ret = drm_client_modeset_commit_locked(&fb_helper->client);
1659 info->var.xoffset = var->xoffset;
1660 info->var.yoffset = var->yoffset;
1662 pan_set(fb_helper, info->var.xoffset, info->var.yoffset);
1667 static int pan_display_legacy(struct fb_var_screeninfo *var,
1668 struct fb_info *info)
1670 struct drm_fb_helper *fb_helper = info->par;
1671 struct drm_client_dev *client = &fb_helper->client;
1672 struct drm_mode_set *modeset;
1675 mutex_lock(&client->modeset_mutex);
1676 drm_modeset_lock_all(fb_helper->dev);
1677 drm_client_for_each_modeset(modeset, client) {
1678 modeset->x = var->xoffset;
1679 modeset->y = var->yoffset;
1681 if (modeset->num_connectors) {
1682 ret = drm_mode_set_config_internal(modeset);
1684 info->var.xoffset = var->xoffset;
1685 info->var.yoffset = var->yoffset;
1689 drm_modeset_unlock_all(fb_helper->dev);
1690 mutex_unlock(&client->modeset_mutex);
1696 * drm_fb_helper_pan_display - implementation for &fb_ops.fb_pan_display
1697 * @var: updated screen information
1698 * @info: fbdev registered by the helper
1700 int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
1701 struct fb_info *info)
1703 struct drm_fb_helper *fb_helper = info->par;
1704 struct drm_device *dev = fb_helper->dev;
1707 if (oops_in_progress)
1710 mutex_lock(&fb_helper->lock);
1711 if (!drm_master_internal_acquire(dev)) {
1716 if (drm_drv_uses_atomic_modeset(dev))
1717 ret = pan_display_atomic(var, info);
1719 ret = pan_display_legacy(var, info);
1721 drm_master_internal_release(dev);
1723 mutex_unlock(&fb_helper->lock);
1727 EXPORT_SYMBOL(drm_fb_helper_pan_display);
1729 static uint32_t drm_fb_helper_find_format(struct drm_fb_helper *fb_helper, const uint32_t *formats,
1730 size_t format_count, uint32_t bpp, uint32_t depth)
1732 struct drm_device *dev = fb_helper->dev;
1737 * Do not consider YUV or other complicated formats
1738 * for framebuffers. This means only legacy formats
1739 * are supported (fmt->depth is a legacy field), but
1740 * the framebuffer emulation can only deal with such
1741 * formats, specifically RGB/BGA formats.
1743 format = drm_mode_legacy_fb_format(bpp, depth);
1747 for (i = 0; i < format_count; ++i) {
1748 if (formats[i] == format)
1753 /* We found nothing. */
1754 drm_warn(dev, "bpp/depth value of %u/%u not supported\n", bpp, depth);
1756 return DRM_FORMAT_INVALID;
1759 static uint32_t drm_fb_helper_find_cmdline_format(struct drm_fb_helper *fb_helper,
1760 const uint32_t *formats, size_t format_count,
1761 const struct drm_cmdline_mode *cmdline_mode)
1763 struct drm_device *dev = fb_helper->dev;
1764 uint32_t bpp, depth;
1766 if (!cmdline_mode->bpp_specified)
1767 return DRM_FORMAT_INVALID;
1769 switch (cmdline_mode->bpp) {
1776 bpp = depth = cmdline_mode->bpp;
1787 drm_info(dev, "unsupported bpp value of %d\n", cmdline_mode->bpp);
1788 return DRM_FORMAT_INVALID;
1791 return drm_fb_helper_find_format(fb_helper, formats, format_count, bpp, depth);
1794 static int __drm_fb_helper_find_sizes(struct drm_fb_helper *fb_helper, int preferred_bpp,
1795 struct drm_fb_helper_surface_size *sizes)
1797 struct drm_client_dev *client = &fb_helper->client;
1798 struct drm_device *dev = fb_helper->dev;
1800 struct drm_connector_list_iter conn_iter;
1801 struct drm_connector *connector;
1802 struct drm_mode_set *mode_set;
1803 uint32_t surface_format = DRM_FORMAT_INVALID;
1804 const struct drm_format_info *info;
1806 memset(sizes, 0, sizeof(*sizes));
1807 sizes->fb_width = (u32)-1;
1808 sizes->fb_height = (u32)-1;
1810 drm_client_for_each_modeset(mode_set, client) {
1811 struct drm_crtc *crtc = mode_set->crtc;
1812 struct drm_plane *plane = crtc->primary;
1814 drm_dbg_kms(dev, "test CRTC %u primary plane\n", drm_crtc_index(crtc));
1816 drm_connector_list_iter_begin(fb_helper->dev, &conn_iter);
1817 drm_client_for_each_connector_iter(connector, &conn_iter) {
1818 struct drm_cmdline_mode *cmdline_mode = &connector->cmdline_mode;
1820 surface_format = drm_fb_helper_find_cmdline_format(fb_helper,
1821 plane->format_types,
1822 plane->format_count,
1824 if (surface_format != DRM_FORMAT_INVALID)
1825 break; /* found supported format */
1827 drm_connector_list_iter_end(&conn_iter);
1829 if (surface_format != DRM_FORMAT_INVALID)
1830 break; /* found supported format */
1832 /* try preferred bpp/depth */
1833 surface_format = drm_fb_helper_find_format(fb_helper, plane->format_types,
1834 plane->format_count, preferred_bpp,
1835 dev->mode_config.preferred_depth);
1836 if (surface_format != DRM_FORMAT_INVALID)
1837 break; /* found supported format */
1840 if (surface_format == DRM_FORMAT_INVALID) {
1841 drm_warn(dev, "No compatible format found\n");
1845 info = drm_format_info(surface_format);
1846 sizes->surface_bpp = drm_format_info_bpp(info, 0);
1847 sizes->surface_depth = info->depth;
1849 /* first up get a count of crtcs now in use and new min/maxes width/heights */
1851 drm_client_for_each_modeset(mode_set, client) {
1852 struct drm_display_mode *desired_mode;
1854 /* in case of tile group, are we the last tile vert or horiz?
1855 * If no tile group you are always the last one both vertically
1858 bool lastv = true, lasth = true;
1860 desired_mode = mode_set->mode;
1870 sizes->surface_width =
1871 max_t(u32, desired_mode->hdisplay + x, sizes->surface_width);
1872 sizes->surface_height =
1873 max_t(u32, desired_mode->vdisplay + y, sizes->surface_height);
1875 for (j = 0; j < mode_set->num_connectors; j++) {
1876 struct drm_connector *connector = mode_set->connectors[j];
1878 if (connector->has_tile &&
1879 desired_mode->hdisplay == connector->tile_h_size &&
1880 desired_mode->vdisplay == connector->tile_v_size) {
1881 lasth = (connector->tile_h_loc == (connector->num_h_tile - 1));
1882 lastv = (connector->tile_v_loc == (connector->num_v_tile - 1));
1883 /* cloning to multiple tiles is just crazy-talk, so: */
1889 sizes->fb_width = min_t(u32, desired_mode->hdisplay + x, sizes->fb_width);
1891 sizes->fb_height = min_t(u32, desired_mode->vdisplay + y, sizes->fb_height);
1894 if (crtc_count == 0 || sizes->fb_width == -1 || sizes->fb_height == -1) {
1895 drm_info(dev, "Cannot find any crtc or sizes\n");
1902 static int drm_fb_helper_find_sizes(struct drm_fb_helper *fb_helper, int preferred_bpp,
1903 struct drm_fb_helper_surface_size *sizes)
1905 struct drm_client_dev *client = &fb_helper->client;
1906 struct drm_device *dev = fb_helper->dev;
1907 struct drm_mode_config *config = &dev->mode_config;
1910 mutex_lock(&client->modeset_mutex);
1911 ret = __drm_fb_helper_find_sizes(fb_helper, preferred_bpp, sizes);
1912 mutex_unlock(&client->modeset_mutex);
1917 /* Handle our overallocation */
1918 sizes->surface_height *= drm_fbdev_overalloc;
1919 sizes->surface_height /= 100;
1920 if (sizes->surface_height > config->max_height) {
1921 drm_dbg_kms(dev, "Fbdev over-allocation too large; clamping height to %d\n",
1922 config->max_height);
1923 sizes->surface_height = config->max_height;
1930 * Allocates the backing storage and sets up the fbdev info structure through
1931 * the ->fb_probe callback.
1933 static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper,
1936 struct drm_client_dev *client = &fb_helper->client;
1937 struct drm_fb_helper_surface_size sizes;
1940 ret = drm_fb_helper_find_sizes(fb_helper, preferred_bpp, &sizes);
1942 /* First time: disable all crtc's.. */
1943 if (!fb_helper->deferred_setup)
1944 drm_client_modeset_commit(client);
1948 #if IS_ENABLED(CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM)
1949 fb_helper->hint_leak_smem_start = drm_leak_fbdev_smem;
1952 /* push down into drivers */
1953 ret = (*fb_helper->funcs->fb_probe)(fb_helper, &sizes);
1957 strcpy(fb_helper->fb->comm, "[fbcon]");
1961 static void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
1962 bool is_color_indexed)
1964 info->fix.type = FB_TYPE_PACKED_PIXELS;
1965 info->fix.visual = is_color_indexed ? FB_VISUAL_PSEUDOCOLOR
1966 : FB_VISUAL_TRUECOLOR;
1967 info->fix.mmio_start = 0;
1968 info->fix.mmio_len = 0;
1969 info->fix.type_aux = 0;
1970 info->fix.xpanstep = 1; /* doing it in hw */
1971 info->fix.ypanstep = 1; /* doing it in hw */
1972 info->fix.ywrapstep = 0;
1973 info->fix.accel = FB_ACCEL_NONE;
1975 info->fix.line_length = pitch;
1978 static void drm_fb_helper_fill_var(struct fb_info *info,
1979 struct drm_fb_helper *fb_helper,
1980 uint32_t fb_width, uint32_t fb_height)
1982 struct drm_framebuffer *fb = fb_helper->fb;
1983 const struct drm_format_info *format = fb->format;
1985 switch (format->format) {
1989 /* supported format with sub-byte pixels */
1993 WARN_ON((drm_format_info_block_width(format, 0) > 1) ||
1994 (drm_format_info_block_height(format, 0) > 1));
1998 info->pseudo_palette = fb_helper->pseudo_palette;
1999 info->var.xres_virtual = fb->width;
2000 info->var.yres_virtual = fb->height;
2001 info->var.bits_per_pixel = drm_format_info_bpp(format, 0);
2002 info->var.accel_flags = FB_ACCELF_TEXT;
2003 info->var.xoffset = 0;
2004 info->var.yoffset = 0;
2005 info->var.activate = FB_ACTIVATE_NOW;
2007 drm_fb_helper_fill_pixel_fmt(&info->var, format);
2009 info->var.xres = fb_width;
2010 info->var.yres = fb_height;
2014 * drm_fb_helper_fill_info - initializes fbdev information
2015 * @info: fbdev instance to set up
2016 * @fb_helper: fb helper instance to use as template
2017 * @sizes: describes fbdev size and scanout surface size
2019 * Sets up the variable and fixed fbdev metainformation from the given fb helper
2020 * instance and the drm framebuffer allocated in &drm_fb_helper.fb.
2022 * Drivers should call this (or their equivalent setup code) from their
2023 * &drm_fb_helper_funcs.fb_probe callback after having allocated the fbdev
2024 * backing storage framebuffer.
2026 void drm_fb_helper_fill_info(struct fb_info *info,
2027 struct drm_fb_helper *fb_helper,
2028 struct drm_fb_helper_surface_size *sizes)
2030 struct drm_framebuffer *fb = fb_helper->fb;
2032 drm_fb_helper_fill_fix(info, fb->pitches[0],
2033 fb->format->is_color_indexed);
2034 drm_fb_helper_fill_var(info, fb_helper,
2035 sizes->fb_width, sizes->fb_height);
2037 info->par = fb_helper;
2039 * The DRM drivers fbdev emulation device name can be confusing if the
2040 * driver name also has a "drm" suffix on it. Leading to names such as
2041 * "simpledrmdrmfb" in /proc/fb. Unfortunately, it's an uAPI and can't
2042 * be changed due user-space tools (e.g: pm-utils) matching against it.
2044 snprintf(info->fix.id, sizeof(info->fix.id), "%sdrmfb",
2045 fb_helper->dev->driver->name);
2048 EXPORT_SYMBOL(drm_fb_helper_fill_info);
2051 * This is a continuation of drm_setup_crtcs() that sets up anything related
2052 * to the framebuffer. During initialization, drm_setup_crtcs() is called before
2053 * the framebuffer has been allocated (fb_helper->fb and fb_helper->info).
2054 * So, any setup that touches those fields needs to be done here instead of in
2055 * drm_setup_crtcs().
2057 static void drm_setup_crtcs_fb(struct drm_fb_helper *fb_helper)
2059 struct drm_client_dev *client = &fb_helper->client;
2060 struct drm_connector_list_iter conn_iter;
2061 struct fb_info *info = fb_helper->info;
2062 unsigned int rotation, sw_rotations = 0;
2063 struct drm_connector *connector;
2064 struct drm_mode_set *modeset;
2066 mutex_lock(&client->modeset_mutex);
2067 drm_client_for_each_modeset(modeset, client) {
2068 if (!modeset->num_connectors)
2071 modeset->fb = fb_helper->fb;
2073 if (drm_client_rotation(modeset, &rotation))
2074 /* Rotating in hardware, fbcon should not rotate */
2075 sw_rotations |= DRM_MODE_ROTATE_0;
2077 sw_rotations |= rotation;
2079 mutex_unlock(&client->modeset_mutex);
2081 drm_connector_list_iter_begin(fb_helper->dev, &conn_iter);
2082 drm_client_for_each_connector_iter(connector, &conn_iter) {
2084 /* use first connected connector for the physical dimensions */
2085 if (connector->status == connector_status_connected) {
2086 info->var.width = connector->display_info.width_mm;
2087 info->var.height = connector->display_info.height_mm;
2091 drm_connector_list_iter_end(&conn_iter);
2093 switch (sw_rotations) {
2094 case DRM_MODE_ROTATE_0:
2095 info->fbcon_rotate_hint = FB_ROTATE_UR;
2097 case DRM_MODE_ROTATE_90:
2098 info->fbcon_rotate_hint = FB_ROTATE_CCW;
2100 case DRM_MODE_ROTATE_180:
2101 info->fbcon_rotate_hint = FB_ROTATE_UD;
2103 case DRM_MODE_ROTATE_270:
2104 info->fbcon_rotate_hint = FB_ROTATE_CW;
2108 * Multiple bits are set / multiple rotations requested
2109 * fbcon cannot handle separate rotation settings per
2110 * output, so fallback to unrotated.
2112 info->fbcon_rotate_hint = FB_ROTATE_UR;
2116 /* Note: Drops fb_helper->lock before returning. */
2118 __drm_fb_helper_initial_config_and_unlock(struct drm_fb_helper *fb_helper,
2121 struct drm_device *dev = fb_helper->dev;
2122 struct fb_info *info;
2123 unsigned int width, height;
2126 width = dev->mode_config.max_width;
2127 height = dev->mode_config.max_height;
2129 drm_client_modeset_probe(&fb_helper->client, width, height);
2130 ret = drm_fb_helper_single_fb_probe(fb_helper, bpp_sel);
2132 if (ret == -EAGAIN) {
2133 fb_helper->preferred_bpp = bpp_sel;
2134 fb_helper->deferred_setup = true;
2137 mutex_unlock(&fb_helper->lock);
2141 drm_setup_crtcs_fb(fb_helper);
2143 fb_helper->deferred_setup = false;
2145 info = fb_helper->info;
2146 info->var.pixclock = 0;
2147 /* Shamelessly allow physical address leaking to userspace */
2148 #if IS_ENABLED(CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM)
2149 if (!fb_helper->hint_leak_smem_start)
2151 /* don't leak any physical addresses to userspace */
2152 info->flags |= FBINFO_HIDE_SMEM_START;
2154 /* Need to drop locks to avoid recursive deadlock in
2155 * register_framebuffer. This is ok because the only thing left to do is
2156 * register the fbdev emulation instance in kernel_fb_helper_list. */
2157 mutex_unlock(&fb_helper->lock);
2159 ret = register_framebuffer(info);
2163 drm_info(dev, "fb%d: %s frame buffer device\n",
2164 info->node, info->fix.id);
2166 mutex_lock(&kernel_fb_helper_lock);
2167 if (list_empty(&kernel_fb_helper_list))
2168 register_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
2170 list_add(&fb_helper->kernel_fb_list, &kernel_fb_helper_list);
2171 mutex_unlock(&kernel_fb_helper_lock);
2177 * drm_fb_helper_initial_config - setup a sane initial connector configuration
2178 * @fb_helper: fb_helper device struct
2179 * @bpp_sel: bpp value to use for the framebuffer configuration
2181 * Scans the CRTCs and connectors and tries to put together an initial setup.
2182 * At the moment, this is a cloned configuration across all heads with
2183 * a new framebuffer object as the backing store.
2185 * Note that this also registers the fbdev and so allows userspace to call into
2186 * the driver through the fbdev interfaces.
2188 * This function will call down into the &drm_fb_helper_funcs.fb_probe callback
2189 * to let the driver allocate and initialize the fbdev info structure and the
2190 * drm framebuffer used to back the fbdev. drm_fb_helper_fill_info() is provided
2191 * as a helper to setup simple default values for the fbdev info structure.
2195 * When you have fbcon support built-in or already loaded, this function will do
2196 * a full modeset to setup the fbdev console. Due to locking misdesign in the
2197 * VT/fbdev subsystem that entire modeset sequence has to be done while holding
2198 * console_lock. Until console_unlock is called no dmesg lines will be sent out
2199 * to consoles, not even serial console. This means when your driver crashes,
2200 * you will see absolutely nothing else but a system stuck in this function,
2201 * with no further output. Any kind of printk() you place within your own driver
2202 * or in the drm core modeset code will also never show up.
2204 * Standard debug practice is to run the fbcon setup without taking the
2205 * console_lock as a hack, to be able to see backtraces and crashes on the
2206 * serial line. This can be done by setting the fb.lockless_register_fb=1 kernel
2209 * The other option is to just disable fbdev emulation since very likely the
2210 * first modeset from userspace will crash in the same way, and is even easier
2211 * to debug. This can be done by setting the drm_kms_helper.fbdev_emulation=0
2212 * kernel cmdline option.
2215 * Zero if everything went ok, nonzero otherwise.
2217 int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper, int bpp_sel)
2221 if (!drm_fbdev_emulation)
2224 mutex_lock(&fb_helper->lock);
2225 ret = __drm_fb_helper_initial_config_and_unlock(fb_helper, bpp_sel);
2229 EXPORT_SYMBOL(drm_fb_helper_initial_config);
2232 * drm_fb_helper_hotplug_event - respond to a hotplug notification by
2233 * probing all the outputs attached to the fb
2234 * @fb_helper: driver-allocated fbdev helper, can be NULL
2236 * Scan the connectors attached to the fb_helper and try to put together a
2237 * setup after notification of a change in output configuration.
2239 * Called at runtime, takes the mode config locks to be able to check/change the
2240 * modeset configuration. Must be run from process context (which usually means
2241 * either the output polling work or a work item launched from the driver's
2242 * hotplug interrupt).
2244 * Note that drivers may call this even before calling
2245 * drm_fb_helper_initial_config but only after drm_fb_helper_init. This allows
2246 * for a race-free fbcon setup and will make sure that the fbdev emulation will
2247 * not miss any hotplug events.
2250 * 0 on success and a non-zero error code otherwise.
2252 int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
2256 if (!drm_fbdev_emulation || !fb_helper)
2259 mutex_lock(&fb_helper->lock);
2260 if (fb_helper->deferred_setup) {
2261 err = __drm_fb_helper_initial_config_and_unlock(fb_helper,
2262 fb_helper->preferred_bpp);
2266 if (!fb_helper->fb || !drm_master_internal_acquire(fb_helper->dev)) {
2267 fb_helper->delayed_hotplug = true;
2268 mutex_unlock(&fb_helper->lock);
2272 drm_master_internal_release(fb_helper->dev);
2274 drm_dbg_kms(fb_helper->dev, "\n");
2276 drm_client_modeset_probe(&fb_helper->client, fb_helper->fb->width, fb_helper->fb->height);
2277 drm_setup_crtcs_fb(fb_helper);
2278 mutex_unlock(&fb_helper->lock);
2280 drm_fb_helper_set_par(fb_helper->info);
2284 EXPORT_SYMBOL(drm_fb_helper_hotplug_event);
2287 * drm_fb_helper_lastclose - DRM driver lastclose helper for fbdev emulation
2290 * This function can be used as the &drm_driver->lastclose callback for drivers
2291 * that only need to call drm_fb_helper_restore_fbdev_mode_unlocked().
2293 void drm_fb_helper_lastclose(struct drm_device *dev)
2295 drm_fb_helper_restore_fbdev_mode_unlocked(dev->fb_helper);
2297 EXPORT_SYMBOL(drm_fb_helper_lastclose);
2300 * drm_fb_helper_output_poll_changed - DRM mode config \.output_poll_changed
2301 * helper for fbdev emulation
2304 * This function can be used as the
2305 * &drm_mode_config_funcs.output_poll_changed callback for drivers that only
2306 * need to call drm_fbdev.hotplug_event().
2308 void drm_fb_helper_output_poll_changed(struct drm_device *dev)
2310 drm_fb_helper_hotplug_event(dev->fb_helper);
2312 EXPORT_SYMBOL(drm_fb_helper_output_poll_changed);