/* * Copyright (c) 2006-2009 Red Hat Inc. * Copyright (c) 2006-2008 Intel Corporation * Copyright (c) 2007 Dave Airlie * * DRM framebuffer helper functions * * Permission to use, copy, modify, distribute, and sell this software and its * documentation for any purpose is hereby granted without fee, provided that * the above copyright notice appear in all copies and that both that copyright * notice and this permission notice appear in supporting documentation, and * that the name of the copyright holders not be used in advertising or * publicity pertaining to distribution of the software without specific, * written prior permission. The copyright holders make no representations * about the suitability of this software for any purpose. It is provided "as * is" without express or implied warranty. * * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE * OF THIS SOFTWARE. * * Authors: * Dave Airlie * Jesse Barnes */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "drm_crtc_helper_internal.h" #include "drm_internal.h" static bool drm_fbdev_emulation = true; module_param_named(fbdev_emulation, drm_fbdev_emulation, bool, 0600); MODULE_PARM_DESC(fbdev_emulation, "Enable legacy fbdev emulation [default=true]"); static int drm_fbdev_overalloc = CONFIG_DRM_FBDEV_OVERALLOC; module_param(drm_fbdev_overalloc, int, 0444); MODULE_PARM_DESC(drm_fbdev_overalloc, "Overallocation of the fbdev buffer (%) [default=" __MODULE_STRING(CONFIG_DRM_FBDEV_OVERALLOC) "]"); /* * In order to keep user-space compatibility, we want in certain use-cases * to keep leaking the fbdev physical address to the user-space program * handling the fbdev buffer. * This is a bad habit essentially kept into closed source opengl driver * that should really be moved into open-source upstream projects instead * of using legacy physical addresses in user space to communicate with * other out-of-tree kernel modules. * * This module_param *should* be removed as soon as possible and be * considered as a broken and legacy behaviour from a modern fbdev device. */ #if IS_ENABLED(CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM) static bool drm_leak_fbdev_smem = false; module_param_unsafe(drm_leak_fbdev_smem, bool, 0600); MODULE_PARM_DESC(drm_leak_fbdev_smem, "Allow unsafe leaking fbdev physical smem address [default=false]"); #endif static LIST_HEAD(kernel_fb_helper_list); static DEFINE_MUTEX(kernel_fb_helper_lock); /** * DOC: fbdev helpers * * The fb helper functions are useful to provide an fbdev on top of a drm kernel * mode setting driver. They can be used mostly independently from the crtc * helper functions used by many drivers to implement the kernel mode setting * interfaces. * * Drivers that support a dumb buffer with a virtual address and mmap support, * should try out the generic fbdev emulation using drm_fbdev_generic_setup(). * It will automatically set up deferred I/O if the driver requires a shadow * buffer. * * At runtime drivers should restore the fbdev console by using * drm_fb_helper_lastclose() as their &drm_driver.lastclose callback. * They should also notify the fb helper code from updates to the output * configuration by using drm_fb_helper_output_poll_changed() as their * &drm_mode_config_funcs.output_poll_changed callback. * * For suspend/resume consider using drm_mode_config_helper_suspend() and * drm_mode_config_helper_resume() which takes care of fbdev as well. * * All other functions exported by the fb helper library can be used to * implement the fbdev driver interface by the driver. * * It is possible, though perhaps somewhat tricky, to implement race-free * hotplug detection using the fbdev helpers. The drm_fb_helper_prepare() * helper must be called first to initialize the minimum required to make * hotplug detection work. Drivers also need to make sure to properly set up * the &drm_mode_config.funcs member. After calling drm_kms_helper_poll_init() * it is safe to enable interrupts and start processing hotplug events. At the * same time, drivers should initialize all modeset objects such as CRTCs, * encoders and connectors. To finish up the fbdev helper initialization, the * drm_fb_helper_init() function is called. To probe for all attached displays * and set up an initial configuration using the detected hardware, drivers * should call drm_fb_helper_initial_config(). * * If &drm_framebuffer_funcs.dirty is set, the * drm_fb_helper_{cfb,sys}_{write,fillrect,copyarea,imageblit} functions will * accumulate changes and schedule &drm_fb_helper.dirty_work to run right * away. This worker then calls the dirty() function ensuring that it will * always run in process context since the fb_*() function could be running in * atomic context. If drm_fb_helper_deferred_io() is used as the deferred_io * callback it will also schedule dirty_work with the damage collected from the * mmap page writes. * * Deferred I/O is not compatible with SHMEM. Such drivers should request an * fbdev shadow buffer and call drm_fbdev_generic_setup() instead. */ static void drm_fb_helper_restore_lut_atomic(struct drm_crtc *crtc) { uint16_t *r_base, *g_base, *b_base; if (crtc->funcs->gamma_set == NULL) return; r_base = crtc->gamma_store; g_base = r_base + crtc->gamma_size; b_base = g_base + crtc->gamma_size; crtc->funcs->gamma_set(crtc, r_base, g_base, b_base, crtc->gamma_size, NULL); } /** * drm_fb_helper_debug_enter - implementation for &fb_ops.fb_debug_enter * @info: fbdev registered by the helper */ int drm_fb_helper_debug_enter(struct fb_info *info) { struct drm_fb_helper *helper = info->par; const struct drm_crtc_helper_funcs *funcs; struct drm_mode_set *mode_set; list_for_each_entry(helper, &kernel_fb_helper_list, kernel_fb_list) { mutex_lock(&helper->client.modeset_mutex); drm_client_for_each_modeset(mode_set, &helper->client) { if (!mode_set->crtc->enabled) continue; funcs = mode_set->crtc->helper_private; if (funcs->mode_set_base_atomic == NULL) continue; if (drm_drv_uses_atomic_modeset(mode_set->crtc->dev)) continue; funcs->mode_set_base_atomic(mode_set->crtc, mode_set->fb, mode_set->x, mode_set->y, ENTER_ATOMIC_MODE_SET); } mutex_unlock(&helper->client.modeset_mutex); } return 0; } EXPORT_SYMBOL(drm_fb_helper_debug_enter); /** * drm_fb_helper_debug_leave - implementation for &fb_ops.fb_debug_leave * @info: fbdev registered by the helper */ int drm_fb_helper_debug_leave(struct fb_info *info) { struct drm_fb_helper *helper = info->par; struct drm_client_dev *client = &helper->client; struct drm_device *dev = helper->dev; struct drm_crtc *crtc; const struct drm_crtc_helper_funcs *funcs; struct drm_mode_set *mode_set; struct drm_framebuffer *fb; mutex_lock(&client->modeset_mutex); drm_client_for_each_modeset(mode_set, client) { crtc = mode_set->crtc; if (drm_drv_uses_atomic_modeset(crtc->dev)) continue; funcs = crtc->helper_private; fb = crtc->primary->fb; if (!crtc->enabled) continue; if (!fb) { drm_err(dev, "no fb to restore?\n"); continue; } if (funcs->mode_set_base_atomic == NULL) continue; drm_fb_helper_restore_lut_atomic(mode_set->crtc); funcs->mode_set_base_atomic(mode_set->crtc, fb, crtc->x, crtc->y, LEAVE_ATOMIC_MODE_SET); } mutex_unlock(&client->modeset_mutex); return 0; } EXPORT_SYMBOL(drm_fb_helper_debug_leave); static int __drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper, bool force) { bool do_delayed; int ret; if (!drm_fbdev_emulation || !fb_helper) return -ENODEV; if (READ_ONCE(fb_helper->deferred_setup)) return 0; mutex_lock(&fb_helper->lock); if (force) { /* * Yes this is the _locked version which expects the master lock * to be held. But for forced restores we're intentionally * racing here, see drm_fb_helper_set_par(). */ ret = drm_client_modeset_commit_locked(&fb_helper->client); } else { ret = drm_client_modeset_commit(&fb_helper->client); } do_delayed = fb_helper->delayed_hotplug; if (do_delayed) fb_helper->delayed_hotplug = false; mutex_unlock(&fb_helper->lock); if (do_delayed) drm_fb_helper_hotplug_event(fb_helper); return ret; } /** * drm_fb_helper_restore_fbdev_mode_unlocked - restore fbdev configuration * @fb_helper: driver-allocated fbdev helper, can be NULL * * This should be called from driver's drm &drm_driver.lastclose callback * when implementing an fbcon on top of kms using this helper. This ensures that * the user isn't greeted with a black screen when e.g. X dies. * * RETURNS: * Zero if everything went ok, negative error code otherwise. */ int drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper) { return __drm_fb_helper_restore_fbdev_mode_unlocked(fb_helper, false); } EXPORT_SYMBOL(drm_fb_helper_restore_fbdev_mode_unlocked); #ifdef CONFIG_MAGIC_SYSRQ /* emergency restore, don't bother with error reporting */ static void drm_fb_helper_restore_work_fn(struct work_struct *ignored) { struct drm_fb_helper *helper; mutex_lock(&kernel_fb_helper_lock); list_for_each_entry(helper, &kernel_fb_helper_list, kernel_fb_list) { struct drm_device *dev = helper->dev; if (dev->switch_power_state == DRM_SWITCH_POWER_OFF) continue; mutex_lock(&helper->lock); drm_client_modeset_commit_locked(&helper->client); mutex_unlock(&helper->lock); } mutex_unlock(&kernel_fb_helper_lock); } static DECLARE_WORK(drm_fb_helper_restore_work, drm_fb_helper_restore_work_fn); static void drm_fb_helper_sysrq(int dummy1) { schedule_work(&drm_fb_helper_restore_work); } static const struct sysrq_key_op sysrq_drm_fb_helper_restore_op = { .handler = drm_fb_helper_sysrq, .help_msg = "force-fb(v)", .action_msg = "Restore framebuffer console", }; #else static const struct sysrq_key_op sysrq_drm_fb_helper_restore_op = { }; #endif static void drm_fb_helper_dpms(struct fb_info *info, int dpms_mode) { struct drm_fb_helper *fb_helper = info->par; mutex_lock(&fb_helper->lock); drm_client_modeset_dpms(&fb_helper->client, dpms_mode); mutex_unlock(&fb_helper->lock); } /** * drm_fb_helper_blank - implementation for &fb_ops.fb_blank * @blank: desired blanking state * @info: fbdev registered by the helper */ int drm_fb_helper_blank(int blank, struct fb_info *info) { if (oops_in_progress) return -EBUSY; switch (blank) { /* Display: On; HSync: On, VSync: On */ case FB_BLANK_UNBLANK: drm_fb_helper_dpms(info, DRM_MODE_DPMS_ON); break; /* Display: Off; HSync: On, VSync: On */ case FB_BLANK_NORMAL: drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY); break; /* Display: Off; HSync: Off, VSync: On */ case FB_BLANK_HSYNC_SUSPEND: drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY); break; /* Display: Off; HSync: On, VSync: Off */ case FB_BLANK_VSYNC_SUSPEND: drm_fb_helper_dpms(info, DRM_MODE_DPMS_SUSPEND); break; /* Display: Off; HSync: Off, VSync: Off */ case FB_BLANK_POWERDOWN: drm_fb_helper_dpms(info, DRM_MODE_DPMS_OFF); break; } return 0; } EXPORT_SYMBOL(drm_fb_helper_blank); static void drm_fb_helper_resume_worker(struct work_struct *work) { struct drm_fb_helper *helper = container_of(work, struct drm_fb_helper, resume_work); console_lock(); fb_set_suspend(helper->fbdev, 0); console_unlock(); } static void drm_fb_helper_damage_blit_real(struct drm_fb_helper *fb_helper, struct drm_clip_rect *clip, struct dma_buf_map *dst) { struct drm_framebuffer *fb = fb_helper->fb; unsigned int cpp = fb->format->cpp[0]; size_t offset = clip->y1 * fb->pitches[0] + clip->x1 * cpp; void *src = fb_helper->fbdev->screen_buffer + offset; size_t len = (clip->x2 - clip->x1) * cpp; unsigned int y; dma_buf_map_incr(dst, offset); /* go to first pixel within clip rect */ for (y = clip->y1; y < clip->y2; y++) { dma_buf_map_memcpy_to(dst, src, len); dma_buf_map_incr(dst, fb->pitches[0]); src += fb->pitches[0]; } } static int drm_fb_helper_damage_blit(struct drm_fb_helper *fb_helper, struct drm_clip_rect *clip) { struct drm_client_buffer *buffer = fb_helper->buffer; struct dma_buf_map map, dst; int ret; /* * We have to pin the client buffer to its current location while * flushing the shadow buffer. In the general case, concurrent * modesetting operations could try to move the buffer and would * fail. The modeset has to be serialized by acquiring the reservation * object of the underlying BO here. * * For fbdev emulation, we only have to protect against fbdev modeset * operations. Nothing else will involve the client buffer's BO. So it * is sufficient to acquire struct drm_fb_helper.lock here. */ mutex_lock(&fb_helper->lock); ret = drm_client_buffer_vmap(buffer, &map); if (ret) goto out; dst = map; drm_fb_helper_damage_blit_real(fb_helper, clip, &dst); drm_client_buffer_vunmap(buffer); out: mutex_unlock(&fb_helper->lock); return ret; } static void drm_fb_helper_damage_work(struct work_struct *work) { struct drm_fb_helper *helper = container_of(work, struct drm_fb_helper, damage_work); struct drm_device *dev = helper->dev; struct drm_clip_rect *clip = &helper->damage_clip; struct drm_clip_rect clip_copy; unsigned long flags; int ret; spin_lock_irqsave(&helper->damage_lock, flags); clip_copy = *clip; clip->x1 = clip->y1 = ~0; clip->x2 = clip->y2 = 0; spin_unlock_irqrestore(&helper->damage_lock, flags); /* Call damage handlers only if necessary */ if (!(clip_copy.x1 < clip_copy.x2 && clip_copy.y1 < clip_copy.y2)) return; if (helper->buffer) { ret = drm_fb_helper_damage_blit(helper, &clip_copy); if (drm_WARN_ONCE(dev, ret, "Damage blitter failed: ret=%d\n", ret)) goto err; } if (helper->fb->funcs->dirty) { ret = helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, &clip_copy, 1); if (drm_WARN_ONCE(dev, ret, "Dirty helper failed: ret=%d\n", ret)) goto err; } return; err: /* * Restore damage clip rectangle on errors. The next run * of the damage worker will perform the update. */ spin_lock_irqsave(&helper->damage_lock, flags); clip->x1 = min_t(u32, clip->x1, clip_copy.x1); clip->y1 = min_t(u32, clip->y1, clip_copy.y1); clip->x2 = max_t(u32, clip->x2, clip_copy.x2); clip->y2 = max_t(u32, clip->y2, clip_copy.y2); spin_unlock_irqrestore(&helper->damage_lock, flags); } /** * drm_fb_helper_prepare - setup a drm_fb_helper structure * @dev: DRM device * @helper: driver-allocated fbdev helper structure to set up * @funcs: pointer to structure of functions associate with this helper * * Sets up the bare minimum to make the framebuffer helper usable. This is * useful to implement race-free initialization of the polling helpers. */ void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper, const struct drm_fb_helper_funcs *funcs) { INIT_LIST_HEAD(&helper->kernel_fb_list); spin_lock_init(&helper->damage_lock); INIT_WORK(&helper->resume_work, drm_fb_helper_resume_worker); INIT_WORK(&helper->damage_work, drm_fb_helper_damage_work); helper->damage_clip.x1 = helper->damage_clip.y1 = ~0; mutex_init(&helper->lock); helper->funcs = funcs; helper->dev = dev; } EXPORT_SYMBOL(drm_fb_helper_prepare); /** * drm_fb_helper_init - initialize a &struct drm_fb_helper * @dev: drm device * @fb_helper: driver-allocated fbdev helper structure to initialize * * This allocates the structures for the fbdev helper with the given limits. * Note that this won't yet touch the hardware (through the driver interfaces) * nor register the fbdev. This is only done in drm_fb_helper_initial_config() * to allow driver writes more control over the exact init sequence. * * Drivers must call drm_fb_helper_prepare() before calling this function. * * RETURNS: * Zero if everything went ok, nonzero otherwise. */ int drm_fb_helper_init(struct drm_device *dev, struct drm_fb_helper *fb_helper) { int ret; if (!drm_fbdev_emulation) { dev->fb_helper = fb_helper; return 0; } /* * If this is not the generic fbdev client, initialize a drm_client * without callbacks so we can use the modesets. */ if (!fb_helper->client.funcs) { ret = drm_client_init(dev, &fb_helper->client, "drm_fb_helper", NULL); if (ret) return ret; } dev->fb_helper = fb_helper; return 0; } EXPORT_SYMBOL(drm_fb_helper_init); /** * drm_fb_helper_alloc_fbi - allocate fb_info and some of its members * @fb_helper: driver-allocated fbdev helper * * A helper to alloc fb_info and the members cmap and apertures. Called * by the driver within the fb_probe fb_helper callback function. Drivers do not * need to release the allocated fb_info structure themselves, this is * automatically done when calling drm_fb_helper_fini(). * * RETURNS: * fb_info pointer if things went okay, pointer containing error code * otherwise */ struct fb_info *drm_fb_helper_alloc_fbi(struct drm_fb_helper *fb_helper) { struct device *dev = fb_helper->dev->dev; struct fb_info *info; int ret; info = framebuffer_alloc(0, dev); if (!info) return ERR_PTR(-ENOMEM); ret = fb_alloc_cmap(&info->cmap, 256, 0); if (ret) goto err_release; /* * TODO: We really should be smarter here and alloc an aperture * for each IORESOURCE_MEM resource helper->dev->dev has and also * init the ranges of the appertures based on the resources. * Note some drivers currently count on there being only 1 empty * aperture and fill this themselves, these will need to be dealt * with somehow when fixing this. */ info->apertures = alloc_apertures(1); if (!info->apertures) { ret = -ENOMEM; goto err_free_cmap; } fb_helper->fbdev = info; info->skip_vt_switch = true; return info; err_free_cmap: fb_dealloc_cmap(&info->cmap); err_release: framebuffer_release(info); return ERR_PTR(ret); } EXPORT_SYMBOL(drm_fb_helper_alloc_fbi); /** * drm_fb_helper_unregister_fbi - unregister fb_info framebuffer device * @fb_helper: driver-allocated fbdev helper, can be NULL * * A wrapper around unregister_framebuffer, to release the fb_info * framebuffer device. This must be called before releasing all resources for * @fb_helper by calling drm_fb_helper_fini(). */ void drm_fb_helper_unregister_fbi(struct drm_fb_helper *fb_helper) { if (fb_helper && fb_helper->fbdev) unregister_framebuffer(fb_helper->fbdev); } EXPORT_SYMBOL(drm_fb_helper_unregister_fbi); /** * drm_fb_helper_fini - finialize a &struct drm_fb_helper * @fb_helper: driver-allocated fbdev helper, can be NULL * * This cleans up all remaining resources associated with @fb_helper. */ void drm_fb_helper_fini(struct drm_fb_helper *fb_helper) { struct fb_info *info; if (!fb_helper) return; fb_helper->dev->fb_helper = NULL; if (!drm_fbdev_emulation) return; cancel_work_sync(&fb_helper->resume_work); cancel_work_sync(&fb_helper->damage_work); info = fb_helper->fbdev; if (info) { if (info->cmap.len) fb_dealloc_cmap(&info->cmap); framebuffer_release(info); } fb_helper->fbdev = NULL; mutex_lock(&kernel_fb_helper_lock); if (!list_empty(&fb_helper->kernel_fb_list)) { list_del(&fb_helper->kernel_fb_list); if (list_empty(&kernel_fb_helper_list)) unregister_sysrq_key('v', &sysrq_drm_fb_helper_restore_op); } mutex_unlock(&kernel_fb_helper_lock); mutex_destroy(&fb_helper->lock); if (!fb_helper->client.funcs) drm_client_release(&fb_helper->client); } EXPORT_SYMBOL(drm_fb_helper_fini); static bool drm_fbdev_use_shadow_fb(struct drm_fb_helper *fb_helper) { struct drm_device *dev = fb_helper->dev; struct drm_framebuffer *fb = fb_helper->fb; return dev->mode_config.prefer_shadow_fbdev || dev->mode_config.prefer_shadow || fb->funcs->dirty; } static void drm_fb_helper_damage(struct fb_info *info, u32 x, u32 y, u32 width, u32 height) { struct drm_fb_helper *helper = info->par; struct drm_clip_rect *clip = &helper->damage_clip; unsigned long flags; if (!drm_fbdev_use_shadow_fb(helper)) return; spin_lock_irqsave(&helper->damage_lock, flags); clip->x1 = min_t(u32, clip->x1, x); clip->y1 = min_t(u32, clip->y1, y); clip->x2 = max_t(u32, clip->x2, x + width); clip->y2 = max_t(u32, clip->y2, y + height); spin_unlock_irqrestore(&helper->damage_lock, flags); schedule_work(&helper->damage_work); } /** * drm_fb_helper_deferred_io() - fbdev deferred_io callback function * @info: fb_info struct pointer * @pagelist: list of mmap framebuffer pages that have to be flushed * * This function is used as the &fb_deferred_io.deferred_io * callback function for flushing the fbdev mmap writes. */ void drm_fb_helper_deferred_io(struct fb_info *info, struct list_head *pagelist) { unsigned long start, end, min, max; struct page *page; u32 y1, y2; min = ULONG_MAX; max = 0; list_for_each_entry(page, pagelist, lru) { start = page->index << PAGE_SHIFT; end = start + PAGE_SIZE - 1; min = min(min, start); max = max(max, end); } if (min < max) { y1 = min / info->fix.line_length; y2 = min_t(u32, DIV_ROUND_UP(max, info->fix.line_length), info->var.yres); drm_fb_helper_damage(info, 0, y1, info->var.xres, y2 - y1); } } EXPORT_SYMBOL(drm_fb_helper_deferred_io); /** * drm_fb_helper_sys_read - wrapper around fb_sys_read * @info: fb_info struct pointer * @buf: userspace buffer to read from framebuffer memory * @count: number of bytes to read from framebuffer memory * @ppos: read offset within framebuffer memory * * A wrapper around fb_sys_read implemented by fbdev core */ ssize_t drm_fb_helper_sys_read(struct fb_info *info, char __user *buf, size_t count, loff_t *ppos) { return fb_sys_read(info, buf, count, ppos); } EXPORT_SYMBOL(drm_fb_helper_sys_read); /** * drm_fb_helper_sys_write - wrapper around fb_sys_write * @info: fb_info struct pointer * @buf: userspace buffer to write to framebuffer memory * @count: number of bytes to write to framebuffer memory * @ppos: write offset within framebuffer memory * * A wrapper around fb_sys_write implemented by fbdev core */ ssize_t drm_fb_helper_sys_write(struct fb_info *info, const char __user *buf, size_t count, loff_t *ppos) { ssize_t ret; ret = fb_sys_write(info, buf, count, ppos); if (ret > 0) drm_fb_helper_damage(info, 0, 0, info->var.xres, info->var.yres); return ret; } EXPORT_SYMBOL(drm_fb_helper_sys_write); /** * drm_fb_helper_sys_fillrect - wrapper around sys_fillrect * @info: fbdev registered by the helper * @rect: info about rectangle to fill * * A wrapper around sys_fillrect implemented by fbdev core */ void drm_fb_helper_sys_fillrect(struct fb_info *info, const struct fb_fillrect *rect) { sys_fillrect(info, rect); drm_fb_helper_damage(info, rect->dx, rect->dy, rect->width, rect->height); } EXPORT_SYMBOL(drm_fb_helper_sys_fillrect); /** * drm_fb_helper_sys_copyarea - wrapper around sys_copyarea * @info: fbdev registered by the helper * @area: info about area to copy * * A wrapper around sys_copyarea implemented by fbdev core */ void drm_fb_helper_sys_copyarea(struct fb_info *info, const struct fb_copyarea *area) { sys_copyarea(info, area); drm_fb_helper_damage(info, area->dx, area->dy, area->width, area->height); } EXPORT_SYMBOL(drm_fb_helper_sys_copyarea); /** * drm_fb_helper_sys_imageblit - wrapper around sys_imageblit * @info: fbdev registered by the helper * @image: info about image to blit * * A wrapper around sys_imageblit implemented by fbdev core */ void drm_fb_helper_sys_imageblit(struct fb_info *info, const struct fb_image *image) { sys_imageblit(info, image); drm_fb_helper_damage(info, image->dx, image->dy, image->width, image->height); } EXPORT_SYMBOL(drm_fb_helper_sys_imageblit); /** * drm_fb_helper_cfb_fillrect - wrapper around cfb_fillrect * @info: fbdev registered by the helper * @rect: info about rectangle to fill * * A wrapper around cfb_fillrect implemented by fbdev core */ void drm_fb_helper_cfb_fillrect(struct fb_info *info, const struct fb_fillrect *rect) { cfb_fillrect(info, rect); drm_fb_helper_damage(info, rect->dx, rect->dy, rect->width, rect->height); } EXPORT_SYMBOL(drm_fb_helper_cfb_fillrect); /** * drm_fb_helper_cfb_copyarea - wrapper around cfb_copyarea * @info: fbdev registered by the helper * @area: info about area to copy * * A wrapper around cfb_copyarea implemented by fbdev core */ void drm_fb_helper_cfb_copyarea(struct fb_info *info, const struct fb_copyarea *area) { cfb_copyarea(info, area); drm_fb_helper_damage(info, area->dx, area->dy, area->width, area->height); } EXPORT_SYMBOL(drm_fb_helper_cfb_copyarea); /** * drm_fb_helper_cfb_imageblit - wrapper around cfb_imageblit * @info: fbdev registered by the helper * @image: info about image to blit * * A wrapper around cfb_imageblit implemented by fbdev core */ void drm_fb_helper_cfb_imageblit(struct fb_info *info, const struct fb_image *image) { cfb_imageblit(info, image); drm_fb_helper_damage(info, image->dx, image->dy, image->width, image->height); } EXPORT_SYMBOL(drm_fb_helper_cfb_imageblit); /** * drm_fb_helper_set_suspend - wrapper around fb_set_suspend * @fb_helper: driver-allocated fbdev helper, can be NULL * @suspend: whether to suspend or resume * * A wrapper around fb_set_suspend implemented by fbdev core. * Use drm_fb_helper_set_suspend_unlocked() if you don't need to take * the lock yourself */ void drm_fb_helper_set_suspend(struct drm_fb_helper *fb_helper, bool suspend) { if (fb_helper && fb_helper->fbdev) fb_set_suspend(fb_helper->fbdev, suspend); } EXPORT_SYMBOL(drm_fb_helper_set_suspend); /** * drm_fb_helper_set_suspend_unlocked - wrapper around fb_set_suspend that also * takes the console lock * @fb_helper: driver-allocated fbdev helper, can be NULL * @suspend: whether to suspend or resume * * A wrapper around fb_set_suspend() that takes the console lock. If the lock * isn't available on resume, a worker is tasked with waiting for the lock * to become available. The console lock can be pretty contented on resume * due to all the printk activity. * * This function can be called multiple times with the same state since * &fb_info.state is checked to see if fbdev is running or not before locking. * * Use drm_fb_helper_set_suspend() if you need to take the lock yourself. */ void drm_fb_helper_set_suspend_unlocked(struct drm_fb_helper *fb_helper, bool suspend) { if (!fb_helper || !fb_helper->fbdev) return; /* make sure there's no pending/ongoing resume */ flush_work(&fb_helper->resume_work); if (suspend) { if (fb_helper->fbdev->state != FBINFO_STATE_RUNNING) return; console_lock(); } else { if (fb_helper->fbdev->state == FBINFO_STATE_RUNNING) return; if (!console_trylock()) { schedule_work(&fb_helper->resume_work); return; } } fb_set_suspend(fb_helper->fbdev, suspend); console_unlock(); } EXPORT_SYMBOL(drm_fb_helper_set_suspend_unlocked); static int setcmap_pseudo_palette(struct fb_cmap *cmap, struct fb_info *info) { u32 *palette = (u32 *)info->pseudo_palette; int i; if (cmap->start + cmap->len > 16) return -EINVAL; for (i = 0; i < cmap->len; ++i) { u16 red = cmap->red[i]; u16 green = cmap->green[i]; u16 blue = cmap->blue[i]; u32 value; red >>= 16 - info->var.red.length; green >>= 16 - info->var.green.length; blue >>= 16 - info->var.blue.length; value = (red << info->var.red.offset) | (green << info->var.green.offset) | (blue << info->var.blue.offset); if (info->var.transp.length > 0) { u32 mask = (1 << info->var.transp.length) - 1; mask <<= info->var.transp.offset; value |= mask; } palette[cmap->start + i] = value; } return 0; } static int setcmap_legacy(struct fb_cmap *cmap, struct fb_info *info) { struct drm_fb_helper *fb_helper = info->par; struct drm_mode_set *modeset; struct drm_crtc *crtc; u16 *r, *g, *b; int ret = 0; drm_modeset_lock_all(fb_helper->dev); drm_client_for_each_modeset(modeset, &fb_helper->client) { crtc = modeset->crtc; if (!crtc->funcs->gamma_set || !crtc->gamma_size) { ret = -EINVAL; goto out; } if (cmap->start + cmap->len > crtc->gamma_size) { ret = -EINVAL; goto out; } r = crtc->gamma_store; g = r + crtc->gamma_size; b = g + crtc->gamma_size; memcpy(r + cmap->start, cmap->red, cmap->len * sizeof(*r)); memcpy(g + cmap->start, cmap->green, cmap->len * sizeof(*g)); memcpy(b + cmap->start, cmap->blue, cmap->len * sizeof(*b)); ret = crtc->funcs->gamma_set(crtc, r, g, b, crtc->gamma_size, NULL); if (ret) goto out; } out: drm_modeset_unlock_all(fb_helper->dev); return ret; } static struct drm_property_blob *setcmap_new_gamma_lut(struct drm_crtc *crtc, struct fb_cmap *cmap) { struct drm_device *dev = crtc->dev; struct drm_property_blob *gamma_lut; struct drm_color_lut *lut; int size = crtc->gamma_size; int i; if (!size || cmap->start + cmap->len > size) return ERR_PTR(-EINVAL); gamma_lut = drm_property_create_blob(dev, sizeof(*lut) * size, NULL); if (IS_ERR(gamma_lut)) return gamma_lut; lut = gamma_lut->data; if (cmap->start || cmap->len != size) { u16 *r = crtc->gamma_store; u16 *g = r + crtc->gamma_size; u16 *b = g + crtc->gamma_size; for (i = 0; i < cmap->start; i++) { lut[i].red = r[i]; lut[i].green = g[i]; lut[i].blue = b[i]; } for (i = cmap->start + cmap->len; i < size; i++) { lut[i].red = r[i]; lut[i].green = g[i]; lut[i].blue = b[i]; } } for (i = 0; i < cmap->len; i++) { lut[cmap->start + i].red = cmap->red[i]; lut[cmap->start + i].green = cmap->green[i]; lut[cmap->start + i].blue = cmap->blue[i]; } return gamma_lut; } static int setcmap_atomic(struct fb_cmap *cmap, struct fb_info *info) { struct drm_fb_helper *fb_helper = info->par; struct drm_device *dev = fb_helper->dev; struct drm_property_blob *gamma_lut = NULL; struct drm_modeset_acquire_ctx ctx; struct drm_crtc_state *crtc_state; struct drm_atomic_state *state; struct drm_mode_set *modeset; struct drm_crtc *crtc; u16 *r, *g, *b; bool replaced; int ret = 0; drm_modeset_acquire_init(&ctx, 0); state = drm_atomic_state_alloc(dev); if (!state) { ret = -ENOMEM; goto out_ctx; } state->acquire_ctx = &ctx; retry: drm_client_for_each_modeset(modeset, &fb_helper->client) { crtc = modeset->crtc; if (!gamma_lut) gamma_lut = setcmap_new_gamma_lut(crtc, cmap); if (IS_ERR(gamma_lut)) { ret = PTR_ERR(gamma_lut); gamma_lut = NULL; goto out_state; } crtc_state = drm_atomic_get_crtc_state(state, crtc); if (IS_ERR(crtc_state)) { ret = PTR_ERR(crtc_state); goto out_state; } /* * FIXME: This always uses gamma_lut. Some HW have only * degamma_lut, in which case we should reset gamma_lut and set * degamma_lut. See drm_crtc_legacy_gamma_set(). */ replaced = drm_property_replace_blob(&crtc_state->degamma_lut, NULL); replaced |= drm_property_replace_blob(&crtc_state->ctm, NULL); replaced |= drm_property_replace_blob(&crtc_state->gamma_lut, gamma_lut); crtc_state->color_mgmt_changed |= replaced; } ret = drm_atomic_commit(state); if (ret) goto out_state; drm_client_for_each_modeset(modeset, &fb_helper->client) { crtc = modeset->crtc; r = crtc->gamma_store; g = r + crtc->gamma_size; b = g + crtc->gamma_size; memcpy(r + cmap->start, cmap->red, cmap->len * sizeof(*r)); memcpy(g + cmap->start, cmap->green, cmap->len * sizeof(*g)); memcpy(b + cmap->start, cmap->blue, cmap->len * sizeof(*b)); } out_state: if (ret == -EDEADLK) goto backoff; drm_property_blob_put(gamma_lut); drm_atomic_state_put(state); out_ctx: drm_modeset_drop_locks(&ctx); drm_modeset_acquire_fini(&ctx); return ret; backoff: drm_atomic_state_clear(state); drm_modeset_backoff(&ctx); goto retry; } /** * drm_fb_helper_setcmap - implementation for &fb_ops.fb_setcmap * @cmap: cmap to set * @info: fbdev registered by the helper */ int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info) { struct drm_fb_helper *fb_helper = info->par; struct drm_device *dev = fb_helper->dev; int ret; if (oops_in_progress) return -EBUSY; mutex_lock(&fb_helper->lock); if (!drm_master_internal_acquire(dev)) { ret = -EBUSY; goto unlock; } mutex_lock(&fb_helper->client.modeset_mutex); if (info->fix.visual == FB_VISUAL_TRUECOLOR) ret = setcmap_pseudo_palette(cmap, info); else if (drm_drv_uses_atomic_modeset(fb_helper->dev)) ret = setcmap_atomic(cmap, info); else ret = setcmap_legacy(cmap, info); mutex_unlock(&fb_helper->client.modeset_mutex); drm_master_internal_release(dev); unlock: mutex_unlock(&fb_helper->lock); return ret; } EXPORT_SYMBOL(drm_fb_helper_setcmap); /** * drm_fb_helper_ioctl - legacy ioctl implementation * @info: fbdev registered by the helper * @cmd: ioctl command * @arg: ioctl argument * * A helper to implement the standard fbdev ioctl. Only * FBIO_WAITFORVSYNC is implemented for now. */ int drm_fb_helper_ioctl(struct fb_info *info, unsigned int cmd, unsigned long arg) { struct drm_fb_helper *fb_helper = info->par; struct drm_device *dev = fb_helper->dev; struct drm_crtc *crtc; int ret = 0; mutex_lock(&fb_helper->lock); if (!drm_master_internal_acquire(dev)) { ret = -EBUSY; goto unlock; } switch (cmd) { case FBIO_WAITFORVSYNC: /* * Only consider the first CRTC. * * This ioctl is supposed to take the CRTC number as * an argument, but in fbdev times, what that number * was supposed to be was quite unclear, different * drivers were passing that argument differently * (some by reference, some by value), and most of the * userspace applications were just hardcoding 0 as an * argument. * * The first CRTC should be the integrated panel on * most drivers, so this is the best choice we can * make. If we're not smart enough here, one should * just consider switch the userspace to KMS. */ crtc = fb_helper->client.modesets[0].crtc; /* * Only wait for a vblank event if the CRTC is * enabled, otherwise just don't do anythintg, * not even report an error. */ ret = drm_crtc_vblank_get(crtc); if (!ret) { drm_crtc_wait_one_vblank(crtc); drm_crtc_vblank_put(crtc); } ret = 0; break; default: ret = -ENOTTY; } drm_master_internal_release(dev); unlock: mutex_unlock(&fb_helper->lock); return ret; } EXPORT_SYMBOL(drm_fb_helper_ioctl); static bool drm_fb_pixel_format_equal(const struct fb_var_screeninfo *var_1, const struct fb_var_screeninfo *var_2) { return var_1->bits_per_pixel == var_2->bits_per_pixel && var_1->grayscale == var_2->grayscale && var_1->red.offset == var_2->red.offset && var_1->red.length == var_2->red.length && var_1->red.msb_right == var_2->red.msb_right && var_1->green.offset == var_2->green.offset && var_1->green.length == var_2->green.length && var_1->green.msb_right == var_2->green.msb_right && var_1->blue.offset == var_2->blue.offset && var_1->blue.length == var_2->blue.length && var_1->blue.msb_right == var_2->blue.msb_right && var_1->transp.offset == var_2->transp.offset && var_1->transp.length == var_2->transp.length && var_1->transp.msb_right == var_2->transp.msb_right; } static void drm_fb_helper_fill_pixel_fmt(struct fb_var_screeninfo *var, u8 depth) { switch (depth) { case 8: var->red.offset = 0; var->green.offset = 0; var->blue.offset = 0; var->red.length = 8; /* 8bit DAC */ var->green.length = 8; var->blue.length = 8; var->transp.offset = 0; var->transp.length = 0; break; case 15: var->red.offset = 10; var->green.offset = 5; var->blue.offset = 0; var->red.length = 5; var->green.length = 5; var->blue.length = 5; var->transp.offset = 15; var->transp.length = 1; break; case 16: var->red.offset = 11; var->green.offset = 5; var->blue.offset = 0; var->red.length = 5; var->green.length = 6; var->blue.length = 5; var->transp.offset = 0; break; case 24: var->red.offset = 16; var->green.offset = 8; var->blue.offset = 0; var->red.length = 8; var->green.length = 8; var->blue.length = 8; var->transp.offset = 0; var->transp.length = 0; break; case 32: var->red.offset = 16; var->green.offset = 8; var->blue.offset = 0; var->red.length = 8; var->green.length = 8; var->blue.length = 8; var->transp.offset = 24; var->transp.length = 8; break; default: break; } } /** * drm_fb_helper_check_var - implementation for &fb_ops.fb_check_var * @var: screeninfo to check * @info: fbdev registered by the helper */ int drm_fb_helper_check_var(struct fb_var_screeninfo *var, struct fb_info *info) { struct drm_fb_helper *fb_helper = info->par; struct drm_framebuffer *fb = fb_helper->fb; struct drm_device *dev = fb_helper->dev; if (in_dbg_master()) return -EINVAL; if (var->pixclock != 0) { drm_dbg_kms(dev, "fbdev emulation doesn't support changing the pixel clock, value of pixclock is ignored\n"); var->pixclock = 0; } if ((drm_format_info_block_width(fb->format, 0) > 1) || (drm_format_info_block_height(fb->format, 0) > 1)) return -EINVAL; /* * Changes struct fb_var_screeninfo are currently not pushed back * to KMS, hence fail if different settings are requested. */ if (var->bits_per_pixel > fb->format->cpp[0] * 8 || var->xres > fb->width || var->yres > fb->height || var->xres_virtual > fb->width || var->yres_virtual > fb->height) { drm_dbg_kms(dev, "fb requested width/height/bpp can't fit in current fb " "request %dx%d-%d (virtual %dx%d) > %dx%d-%d\n", var->xres, var->yres, var->bits_per_pixel, var->xres_virtual, var->yres_virtual, fb->width, fb->height, fb->format->cpp[0] * 8); return -EINVAL; } var->xres_virtual = fb->width; var->yres_virtual = fb->height; /* * Workaround for SDL 1.2, which is known to be setting all pixel format * fields values to zero in some cases. We treat this situation as a * kind of "use some reasonable autodetected values". */ if (!var->red.offset && !var->green.offset && !var->blue.offset && !var->transp.offset && !var->red.length && !var->green.length && !var->blue.length && !var->transp.length && !var->red.msb_right && !var->green.msb_right && !var->blue.msb_right && !var->transp.msb_right) { drm_fb_helper_fill_pixel_fmt(var, fb->format->depth); } /* * Likewise, bits_per_pixel should be rounded up to a supported value. */ var->bits_per_pixel = fb->format->cpp[0] * 8; /* * drm fbdev emulation doesn't support changing the pixel format at all, * so reject all pixel format changing requests. */ if (!drm_fb_pixel_format_equal(var, &info->var)) { drm_dbg_kms(dev, "fbdev emulation doesn't support changing the pixel format\n"); return -EINVAL; } return 0; } EXPORT_SYMBOL(drm_fb_helper_check_var); /** * drm_fb_helper_set_par - implementation for &fb_ops.fb_set_par * @info: fbdev registered by the helper * * This will let fbcon do the mode init and is called at initialization time by * the fbdev core when registering the driver, and later on through the hotplug * callback. */ int drm_fb_helper_set_par(struct fb_info *info) { struct drm_fb_helper *fb_helper = info->par; struct fb_var_screeninfo *var = &info->var; bool force; if (oops_in_progress) return -EBUSY; if (var->pixclock != 0) { drm_err(fb_helper->dev, "PIXEL CLOCK SET\n"); return -EINVAL; } /* * Normally we want to make sure that a kms master takes precedence over * fbdev, to avoid fbdev flickering and occasionally stealing the * display status. But Xorg first sets the vt back to text mode using * the KDSET IOCTL with KD_TEXT, and only after that drops the master * status when exiting. * * In the past this was caught by drm_fb_helper_lastclose(), but on * modern systems where logind always keeps a drm fd open to orchestrate * the vt switching, this doesn't work. * * To not break the userspace ABI we have this special case here, which * is only used for the above case. Everything else uses the normal * commit function, which ensures that we never steal the display from * an active drm master. */ force = var->activate & FB_ACTIVATE_KD_TEXT; __drm_fb_helper_restore_fbdev_mode_unlocked(fb_helper, force); return 0; } EXPORT_SYMBOL(drm_fb_helper_set_par); static void pan_set(struct drm_fb_helper *fb_helper, int x, int y) { struct drm_mode_set *mode_set; mutex_lock(&fb_helper->client.modeset_mutex); drm_client_for_each_modeset(mode_set, &fb_helper->client) { mode_set->x = x; mode_set->y = y; } mutex_unlock(&fb_helper->client.modeset_mutex); } static int pan_display_atomic(struct fb_var_screeninfo *var, struct fb_info *info) { struct drm_fb_helper *fb_helper = info->par; int ret; pan_set(fb_helper, var->xoffset, var->yoffset); ret = drm_client_modeset_commit_locked(&fb_helper->client); if (!ret) { info->var.xoffset = var->xoffset; info->var.yoffset = var->yoffset; } else pan_set(fb_helper, info->var.xoffset, info->var.yoffset); return ret; } static int pan_display_legacy(struct fb_var_screeninfo *var, struct fb_info *info) { struct drm_fb_helper *fb_helper = info->par; struct drm_client_dev *client = &fb_helper->client; struct drm_mode_set *modeset; int ret = 0; mutex_lock(&client->modeset_mutex); drm_modeset_lock_all(fb_helper->dev); drm_client_for_each_modeset(modeset, client) { modeset->x = var->xoffset; modeset->y = var->yoffset; if (modeset->num_connectors) { ret = drm_mode_set_config_internal(modeset); if (!ret) { info->var.xoffset = var->xoffset; info->var.yoffset = var->yoffset; } } } drm_modeset_unlock_all(fb_helper->dev); mutex_unlock(&client->modeset_mutex); return ret; } /** * drm_fb_helper_pan_display - implementation for &fb_ops.fb_pan_display * @var: updated screen information * @info: fbdev registered by the helper */ int drm_fb_helper_pan_display(struct fb_var_screeninfo *var, struct fb_info *info) { struct drm_fb_helper *fb_helper = info->par; struct drm_device *dev = fb_helper->dev; int ret; if (oops_in_progress) return -EBUSY; mutex_lock(&fb_helper->lock); if (!drm_master_internal_acquire(dev)) { ret = -EBUSY; goto unlock; } if (drm_drv_uses_atomic_modeset(dev)) ret = pan_display_atomic(var, info); else ret = pan_display_legacy(var, info); drm_master_internal_release(dev); unlock: mutex_unlock(&fb_helper->lock); return ret; } EXPORT_SYMBOL(drm_fb_helper_pan_display); /* * Allocates the backing storage and sets up the fbdev info structure through * the ->fb_probe callback. */ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper, int preferred_bpp) { struct drm_client_dev *client = &fb_helper->client; struct drm_device *dev = fb_helper->dev; struct drm_mode_config *config = &dev->mode_config; int ret = 0; int crtc_count = 0; struct drm_connector_list_iter conn_iter; struct drm_fb_helper_surface_size sizes; struct drm_connector *connector; struct drm_mode_set *mode_set; int best_depth = 0; memset(&sizes, 0, sizeof(struct drm_fb_helper_surface_size)); sizes.surface_depth = 24; sizes.surface_bpp = 32; sizes.fb_width = (u32)-1; sizes.fb_height = (u32)-1; /* * If driver picks 8 or 16 by default use that for both depth/bpp * to begin with */ if (preferred_bpp != sizes.surface_bpp) sizes.surface_depth = sizes.surface_bpp = preferred_bpp; drm_connector_list_iter_begin(fb_helper->dev, &conn_iter); drm_client_for_each_connector_iter(connector, &conn_iter) { struct drm_cmdline_mode *cmdline_mode; cmdline_mode = &connector->cmdline_mode; if (cmdline_mode->bpp_specified) { switch (cmdline_mode->bpp) { case 8: sizes.surface_depth = sizes.surface_bpp = 8; break; case 15: sizes.surface_depth = 15; sizes.surface_bpp = 16; break; case 16: sizes.surface_depth = sizes.surface_bpp = 16; break; case 24: sizes.surface_depth = sizes.surface_bpp = 24; break; case 32: sizes.surface_depth = 24; sizes.surface_bpp = 32; break; } break; } } drm_connector_list_iter_end(&conn_iter); /* * If we run into a situation where, for example, the primary plane * supports RGBA5551 (16 bpp, depth 15) but not RGB565 (16 bpp, depth * 16) we need to scale down the depth of the sizes we request. */ mutex_lock(&client->modeset_mutex); drm_client_for_each_modeset(mode_set, client) { struct drm_crtc *crtc = mode_set->crtc; struct drm_plane *plane = crtc->primary; int j; drm_dbg_kms(dev, "test CRTC %u primary plane\n", drm_crtc_index(crtc)); for (j = 0; j < plane->format_count; j++) { const struct drm_format_info *fmt; fmt = drm_format_info(plane->format_types[j]); /* * Do not consider YUV or other complicated formats * for framebuffers. This means only legacy formats * are supported (fmt->depth is a legacy field) but * the framebuffer emulation can only deal with such * formats, specifically RGB/BGA formats. */ if (fmt->depth == 0) continue; /* We found a perfect fit, great */ if (fmt->depth == sizes.surface_depth) { best_depth = fmt->depth; break; } /* Skip depths above what we're looking for */ if (fmt->depth > sizes.surface_depth) continue; /* Best depth found so far */ if (fmt->depth > best_depth) best_depth = fmt->depth; } } if (sizes.surface_depth != best_depth && best_depth) { drm_info(dev, "requested bpp %d, scaled depth down to %d", sizes.surface_bpp, best_depth); sizes.surface_depth = best_depth; } /* first up get a count of crtcs now in use and new min/maxes width/heights */ crtc_count = 0; drm_client_for_each_modeset(mode_set, client) { struct drm_display_mode *desired_mode; int x, y, j; /* in case of tile group, are we the last tile vert or horiz? * If no tile group you are always the last one both vertically * and horizontally */ bool lastv = true, lasth = true; desired_mode = mode_set->mode; if (!desired_mode) continue; crtc_count++; x = mode_set->x; y = mode_set->y; sizes.surface_width = max_t(u32, desired_mode->hdisplay + x, sizes.surface_width); sizes.surface_height = max_t(u32, desired_mode->vdisplay + y, sizes.surface_height); for (j = 0; j < mode_set->num_connectors; j++) { struct drm_connector *connector = mode_set->connectors[j]; if (connector->has_tile && desired_mode->hdisplay == connector->tile_h_size && desired_mode->vdisplay == connector->tile_v_size) { lasth = (connector->tile_h_loc == (connector->num_h_tile - 1)); lastv = (connector->tile_v_loc == (connector->num_v_tile - 1)); /* cloning to multiple tiles is just crazy-talk, so: */ break; } } if (lasth) sizes.fb_width = min_t(u32, desired_mode->hdisplay + x, sizes.fb_width); if (lastv) sizes.fb_height = min_t(u32, desired_mode->vdisplay + y, sizes.fb_height); } mutex_unlock(&client->modeset_mutex); if (crtc_count == 0 || sizes.fb_width == -1 || sizes.fb_height == -1) { drm_info(dev, "Cannot find any crtc or sizes\n"); /* First time: disable all crtc's.. */ if (!fb_helper->deferred_setup) drm_client_modeset_commit(client); return -EAGAIN; } /* Handle our overallocation */ sizes.surface_height *= drm_fbdev_overalloc; sizes.surface_height /= 100; if (sizes.surface_height > config->max_height) { drm_dbg_kms(dev, "Fbdev over-allocation too large; clamping height to %d\n", config->max_height); sizes.surface_height = config->max_height; } /* push down into drivers */ ret = (*fb_helper->funcs->fb_probe)(fb_helper, &sizes); if (ret < 0) return ret; strcpy(fb_helper->fb->comm, "[fbcon]"); return 0; } static void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch, uint32_t depth) { info->fix.type = FB_TYPE_PACKED_PIXELS; info->fix.visual = depth == 8 ? FB_VISUAL_PSEUDOCOLOR : FB_VISUAL_TRUECOLOR; info->fix.mmio_start = 0; info->fix.mmio_len = 0; info->fix.type_aux = 0; info->fix.xpanstep = 1; /* doing it in hw */ info->fix.ypanstep = 1; /* doing it in hw */ info->fix.ywrapstep = 0; info->fix.accel = FB_ACCEL_NONE; info->fix.line_length = pitch; } static void drm_fb_helper_fill_var(struct fb_info *info, struct drm_fb_helper *fb_helper, uint32_t fb_width, uint32_t fb_height) { struct drm_framebuffer *fb = fb_helper->fb; WARN_ON((drm_format_info_block_width(fb->format, 0) > 1) || (drm_format_info_block_height(fb->format, 0) > 1)); info->pseudo_palette = fb_helper->pseudo_palette; info->var.xres_virtual = fb->width; info->var.yres_virtual = fb->height; info->var.bits_per_pixel = fb->format->cpp[0] * 8; info->var.accel_flags = FB_ACCELF_TEXT; info->var.xoffset = 0; info->var.yoffset = 0; info->var.activate = FB_ACTIVATE_NOW; drm_fb_helper_fill_pixel_fmt(&info->var, fb->format->depth); info->var.xres = fb_width; info->var.yres = fb_height; } /** * drm_fb_helper_fill_info - initializes fbdev information * @info: fbdev instance to set up * @fb_helper: fb helper instance to use as template * @sizes: describes fbdev size and scanout surface size * * Sets up the variable and fixed fbdev metainformation from the given fb helper * instance and the drm framebuffer allocated in &drm_fb_helper.fb. * * Drivers should call this (or their equivalent setup code) from their * &drm_fb_helper_funcs.fb_probe callback after having allocated the fbdev * backing storage framebuffer. */ void drm_fb_helper_fill_info(struct fb_info *info, struct drm_fb_helper *fb_helper, struct drm_fb_helper_surface_size *sizes) { struct drm_framebuffer *fb = fb_helper->fb; drm_fb_helper_fill_fix(info, fb->pitches[0], fb->format->depth); drm_fb_helper_fill_var(info, fb_helper, sizes->fb_width, sizes->fb_height); info->par = fb_helper; /* * The DRM drivers fbdev emulation device name can be confusing if the * driver name also has a "drm" suffix on it. Leading to names such as * "simpledrmdrmfb" in /proc/fb. Unfortunately, it's an uAPI and can't * be changed due user-space tools (e.g: pm-utils) matching against it. */ snprintf(info->fix.id, sizeof(info->fix.id), "%sdrmfb", fb_helper->dev->driver->name); } EXPORT_SYMBOL(drm_fb_helper_fill_info); /* * This is a continuation of drm_setup_crtcs() that sets up anything related * to the framebuffer. During initialization, drm_setup_crtcs() is called before * the framebuffer has been allocated (fb_helper->fb and fb_helper->fbdev). * So, any setup that touches those fields needs to be done here instead of in * drm_setup_crtcs(). */ static void drm_setup_crtcs_fb(struct drm_fb_helper *fb_helper) { struct drm_client_dev *client = &fb_helper->client; struct drm_connector_list_iter conn_iter; struct fb_info *info = fb_helper->fbdev; unsigned int rotation, sw_rotations = 0; struct drm_connector *connector; struct drm_mode_set *modeset; mutex_lock(&client->modeset_mutex); drm_client_for_each_modeset(modeset, client) { if (!modeset->num_connectors) continue; modeset->fb = fb_helper->fb; if (drm_client_rotation(modeset, &rotation)) /* Rotating in hardware, fbcon should not rotate */ sw_rotations |= DRM_MODE_ROTATE_0; else sw_rotations |= rotation; } mutex_unlock(&client->modeset_mutex); drm_connector_list_iter_begin(fb_helper->dev, &conn_iter); drm_client_for_each_connector_iter(connector, &conn_iter) { /* use first connected connector for the physical dimensions */ if (connector->status == connector_status_connected) { info->var.width = connector->display_info.width_mm; info->var.height = connector->display_info.height_mm; break; } } drm_connector_list_iter_end(&conn_iter); switch (sw_rotations) { case DRM_MODE_ROTATE_0: info->fbcon_rotate_hint = FB_ROTATE_UR; break; case DRM_MODE_ROTATE_90: info->fbcon_rotate_hint = FB_ROTATE_CCW; break; case DRM_MODE_ROTATE_180: info->fbcon_rotate_hint = FB_ROTATE_UD; break; case DRM_MODE_ROTATE_270: info->fbcon_rotate_hint = FB_ROTATE_CW; break; default: /* * Multiple bits are set / multiple rotations requested * fbcon cannot handle separate rotation settings per * output, so fallback to unrotated. */ info->fbcon_rotate_hint = FB_ROTATE_UR; } } /* Note: Drops fb_helper->lock before returning. */ static int __drm_fb_helper_initial_config_and_unlock(struct drm_fb_helper *fb_helper, int bpp_sel) { struct drm_device *dev = fb_helper->dev; struct fb_info *info; unsigned int width, height; int ret; width = dev->mode_config.max_width; height = dev->mode_config.max_height; drm_client_modeset_probe(&fb_helper->client, width, height); ret = drm_fb_helper_single_fb_probe(fb_helper, bpp_sel); if (ret < 0) { if (ret == -EAGAIN) { fb_helper->preferred_bpp = bpp_sel; fb_helper->deferred_setup = true; ret = 0; } mutex_unlock(&fb_helper->lock); return ret; } drm_setup_crtcs_fb(fb_helper); fb_helper->deferred_setup = false; info = fb_helper->fbdev; info->var.pixclock = 0; /* Shamelessly allow physical address leaking to userspace */ #if IS_ENABLED(CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM) if (!drm_leak_fbdev_smem) #endif /* don't leak any physical addresses to userspace */ info->flags |= FBINFO_HIDE_SMEM_START; /* Need to drop locks to avoid recursive deadlock in * register_framebuffer. This is ok because the only thing left to do is * register the fbdev emulation instance in kernel_fb_helper_list. */ mutex_unlock(&fb_helper->lock); ret = register_framebuffer(info); if (ret < 0) return ret; drm_info(dev, "fb%d: %s frame buffer device\n", info->node, info->fix.id); mutex_lock(&kernel_fb_helper_lock); if (list_empty(&kernel_fb_helper_list)) register_sysrq_key('v', &sysrq_drm_fb_helper_restore_op); list_add(&fb_helper->kernel_fb_list, &kernel_fb_helper_list); mutex_unlock(&kernel_fb_helper_lock); return 0; } /** * drm_fb_helper_initial_config - setup a sane initial connector configuration * @fb_helper: fb_helper device struct * @bpp_sel: bpp value to use for the framebuffer configuration * * Scans the CRTCs and connectors and tries to put together an initial setup. * At the moment, this is a cloned configuration across all heads with * a new framebuffer object as the backing store. * * Note that this also registers the fbdev and so allows userspace to call into * the driver through the fbdev interfaces. * * This function will call down into the &drm_fb_helper_funcs.fb_probe callback * to let the driver allocate and initialize the fbdev info structure and the * drm framebuffer used to back the fbdev. drm_fb_helper_fill_info() is provided * as a helper to setup simple default values for the fbdev info structure. * * HANG DEBUGGING: * * When you have fbcon support built-in or already loaded, this function will do * a full modeset to setup the fbdev console. Due to locking misdesign in the * VT/fbdev subsystem that entire modeset sequence has to be done while holding * console_lock. Until console_unlock is called no dmesg lines will be sent out * to consoles, not even serial console. This means when your driver crashes, * you will see absolutely nothing else but a system stuck in this function, * with no further output. Any kind of printk() you place within your own driver * or in the drm core modeset code will also never show up. * * Standard debug practice is to run the fbcon setup without taking the * console_lock as a hack, to be able to see backtraces and crashes on the * serial line. This can be done by setting the fb.lockless_register_fb=1 kernel * cmdline option. * * The other option is to just disable fbdev emulation since very likely the * first modeset from userspace will crash in the same way, and is even easier * to debug. This can be done by setting the drm_kms_helper.fbdev_emulation=0 * kernel cmdline option. * * RETURNS: * Zero if everything went ok, nonzero otherwise. */ int drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper, int bpp_sel) { int ret; if (!drm_fbdev_emulation) return 0; mutex_lock(&fb_helper->lock); ret = __drm_fb_helper_initial_config_and_unlock(fb_helper, bpp_sel); return ret; } EXPORT_SYMBOL(drm_fb_helper_initial_config); /** * drm_fb_helper_hotplug_event - respond to a hotplug notification by * probing all the outputs attached to the fb * @fb_helper: driver-allocated fbdev helper, can be NULL * * Scan the connectors attached to the fb_helper and try to put together a * setup after notification of a change in output configuration. * * Called at runtime, takes the mode config locks to be able to check/change the * modeset configuration. Must be run from process context (which usually means * either the output polling work or a work item launched from the driver's * hotplug interrupt). * * Note that drivers may call this even before calling * drm_fb_helper_initial_config but only after drm_fb_helper_init. This allows * for a race-free fbcon setup and will make sure that the fbdev emulation will * not miss any hotplug events. * * RETURNS: * 0 on success and a non-zero error code otherwise. */ int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper) { int err = 0; if (!drm_fbdev_emulation || !fb_helper) return 0; mutex_lock(&fb_helper->lock); if (fb_helper->deferred_setup) { err = __drm_fb_helper_initial_config_and_unlock(fb_helper, fb_helper->preferred_bpp); return err; } if (!fb_helper->fb || !drm_master_internal_acquire(fb_helper->dev)) { fb_helper->delayed_hotplug = true; mutex_unlock(&fb_helper->lock); return err; } drm_master_internal_release(fb_helper->dev); drm_dbg_kms(fb_helper->dev, "\n"); drm_client_modeset_probe(&fb_helper->client, fb_helper->fb->width, fb_helper->fb->height); drm_setup_crtcs_fb(fb_helper); mutex_unlock(&fb_helper->lock); drm_fb_helper_set_par(fb_helper->fbdev); return 0; } EXPORT_SYMBOL(drm_fb_helper_hotplug_event); /** * drm_fb_helper_lastclose - DRM driver lastclose helper for fbdev emulation * @dev: DRM device * * This function can be used as the &drm_driver->lastclose callback for drivers * that only need to call drm_fb_helper_restore_fbdev_mode_unlocked(). */ void drm_fb_helper_lastclose(struct drm_device *dev) { drm_fb_helper_restore_fbdev_mode_unlocked(dev->fb_helper); } EXPORT_SYMBOL(drm_fb_helper_lastclose); /** * drm_fb_helper_output_poll_changed - DRM mode config \.output_poll_changed * helper for fbdev emulation * @dev: DRM device * * This function can be used as the * &drm_mode_config_funcs.output_poll_changed callback for drivers that only * need to call drm_fb_helper_hotplug_event(). */ void drm_fb_helper_output_poll_changed(struct drm_device *dev) { drm_fb_helper_hotplug_event(dev->fb_helper); } EXPORT_SYMBOL(drm_fb_helper_output_poll_changed); /* @user: 1=userspace, 0=fbcon */ static int drm_fbdev_fb_open(struct fb_info *info, int user) { struct drm_fb_helper *fb_helper = info->par; /* No need to take a ref for fbcon because it unbinds on unregister */ if (user && !try_module_get(fb_helper->dev->driver->fops->owner)) return -ENODEV; return 0; } static int drm_fbdev_fb_release(struct fb_info *info, int user) { struct drm_fb_helper *fb_helper = info->par; if (user) module_put(fb_helper->dev->driver->fops->owner); return 0; } static void drm_fbdev_cleanup(struct drm_fb_helper *fb_helper) { struct fb_info *fbi = fb_helper->fbdev; void *shadow = NULL; if (!fb_helper->dev) return; if (fbi) { if (fbi->fbdefio) fb_deferred_io_cleanup(fbi); if (drm_fbdev_use_shadow_fb(fb_helper)) shadow = fbi->screen_buffer; } drm_fb_helper_fini(fb_helper); if (shadow) vfree(shadow); else if (fb_helper->buffer) drm_client_buffer_vunmap(fb_helper->buffer); drm_client_framebuffer_delete(fb_helper->buffer); } static void drm_fbdev_release(struct drm_fb_helper *fb_helper) { drm_fbdev_cleanup(fb_helper); drm_client_release(&fb_helper->client); kfree(fb_helper); } /* * fb_ops.fb_destroy is called by the last put_fb_info() call at the end of * unregister_framebuffer() or fb_release(). */ static void drm_fbdev_fb_destroy(struct fb_info *info) { drm_fbdev_release(info->par); } static int drm_fbdev_fb_mmap(struct fb_info *info, struct vm_area_struct *vma) { struct drm_fb_helper *fb_helper = info->par; if (fb_helper->dev->driver->gem_prime_mmap) return fb_helper->dev->driver->gem_prime_mmap(fb_helper->buffer->gem, vma); else return -ENODEV; } static bool drm_fbdev_use_iomem(struct fb_info *info) { struct drm_fb_helper *fb_helper = info->par; struct drm_client_buffer *buffer = fb_helper->buffer; return !drm_fbdev_use_shadow_fb(fb_helper) && buffer->map.is_iomem; } static ssize_t fb_read_screen_base(struct fb_info *info, char __user *buf, size_t count, loff_t pos) { const char __iomem *src = info->screen_base + pos; size_t alloc_size = min_t(size_t, count, PAGE_SIZE); ssize_t ret = 0; int err = 0; char *tmp; tmp = kmalloc(alloc_size, GFP_KERNEL); if (!tmp) return -ENOMEM; while (count) { size_t c = min_t(size_t, count, alloc_size); memcpy_fromio(tmp, src, c); if (copy_to_user(buf, tmp, c)) { err = -EFAULT; break; } src += c; buf += c; ret += c; count -= c; } kfree(tmp); return ret ? ret : err; } static ssize_t fb_read_screen_buffer(struct fb_info *info, char __user *buf, size_t count, loff_t pos) { const char *src = info->screen_buffer + pos; if (copy_to_user(buf, src, count)) return -EFAULT; return count; } static ssize_t drm_fbdev_fb_read(struct fb_info *info, char __user *buf, size_t count, loff_t *ppos) { loff_t pos = *ppos; size_t total_size; ssize_t ret; if (info->screen_size) total_size = info->screen_size; else total_size = info->fix.smem_len; if (pos >= total_size) return 0; if (count >= total_size) count = total_size; if (total_size - count < pos) count = total_size - pos; if (drm_fbdev_use_iomem(info)) ret = fb_read_screen_base(info, buf, count, pos); else ret = fb_read_screen_buffer(info, buf, count, pos); if (ret > 0) *ppos += ret; return ret; } static ssize_t fb_write_screen_base(struct fb_info *info, const char __user *buf, size_t count, loff_t pos) { char __iomem *dst = info->screen_base + pos; size_t alloc_size = min_t(size_t, count, PAGE_SIZE); ssize_t ret = 0; int err = 0; u8 *tmp; tmp = kmalloc(alloc_size, GFP_KERNEL); if (!tmp) return -ENOMEM; while (count) { size_t c = min_t(size_t, count, alloc_size); if (copy_from_user(tmp, buf, c)) { err = -EFAULT; break; } memcpy_toio(dst, tmp, c); dst += c; buf += c; ret += c; count -= c; } kfree(tmp); return ret ? ret : err; } static ssize_t fb_write_screen_buffer(struct fb_info *info, const char __user *buf, size_t count, loff_t pos) { char *dst = info->screen_buffer + pos; if (copy_from_user(dst, buf, count)) return -EFAULT; return count; } static ssize_t drm_fbdev_fb_write(struct fb_info *info, const char __user *buf, size_t count, loff_t *ppos) { loff_t pos = *ppos; size_t total_size; ssize_t ret; int err = 0; if (info->screen_size) total_size = info->screen_size; else total_size = info->fix.smem_len; if (pos > total_size) return -EFBIG; if (count > total_size) { err = -EFBIG; count = total_size; } if (total_size - count < pos) { if (!err) err = -ENOSPC; count = total_size - pos; } /* * Copy to framebuffer even if we already logged an error. Emulates * the behavior of the original fbdev implementation. */ if (drm_fbdev_use_iomem(info)) ret = fb_write_screen_base(info, buf, count, pos); else ret = fb_write_screen_buffer(info, buf, count, pos); if (ret > 0) *ppos += ret; if (ret > 0) drm_fb_helper_damage(info, 0, 0, info->var.xres_virtual, info->var.yres_virtual); return ret ? ret : err; } static void drm_fbdev_fb_fillrect(struct fb_info *info, const struct fb_fillrect *rect) { if (drm_fbdev_use_iomem(info)) drm_fb_helper_cfb_fillrect(info, rect); else drm_fb_helper_sys_fillrect(info, rect); } static void drm_fbdev_fb_copyarea(struct fb_info *info, const struct fb_copyarea *area) { if (drm_fbdev_use_iomem(info)) drm_fb_helper_cfb_copyarea(info, area); else drm_fb_helper_sys_copyarea(info, area); } static void drm_fbdev_fb_imageblit(struct fb_info *info, const struct fb_image *image) { if (drm_fbdev_use_iomem(info)) drm_fb_helper_cfb_imageblit(info, image); else drm_fb_helper_sys_imageblit(info, image); } static const struct fb_ops drm_fbdev_fb_ops = { .owner = THIS_MODULE, DRM_FB_HELPER_DEFAULT_OPS, .fb_open = drm_fbdev_fb_open, .fb_release = drm_fbdev_fb_release, .fb_destroy = drm_fbdev_fb_destroy, .fb_mmap = drm_fbdev_fb_mmap, .fb_read = drm_fbdev_fb_read, .fb_write = drm_fbdev_fb_write, .fb_fillrect = drm_fbdev_fb_fillrect, .fb_copyarea = drm_fbdev_fb_copyarea, .fb_imageblit = drm_fbdev_fb_imageblit, }; static struct fb_deferred_io drm_fbdev_defio = { .delay = HZ / 20, .deferred_io = drm_fb_helper_deferred_io, }; /* * This function uses the client API to create a framebuffer backed by a dumb buffer. * * The _sys_ versions are used for &fb_ops.fb_read, fb_write, fb_fillrect, * fb_copyarea, fb_imageblit. */ static int drm_fb_helper_generic_probe(struct drm_fb_helper *fb_helper, struct drm_fb_helper_surface_size *sizes) { struct drm_client_dev *client = &fb_helper->client; struct drm_device *dev = fb_helper->dev; struct drm_client_buffer *buffer; struct drm_framebuffer *fb; struct fb_info *fbi; u32 format; struct dma_buf_map map; int ret; drm_dbg_kms(dev, "surface width(%d), height(%d) and bpp(%d)\n", sizes->surface_width, sizes->surface_height, sizes->surface_bpp); format = drm_mode_legacy_fb_format(sizes->surface_bpp, sizes->surface_depth); buffer = drm_client_framebuffer_create(client, sizes->surface_width, sizes->surface_height, format); if (IS_ERR(buffer)) return PTR_ERR(buffer); fb_helper->buffer = buffer; fb_helper->fb = buffer->fb; fb = buffer->fb; fbi = drm_fb_helper_alloc_fbi(fb_helper); if (IS_ERR(fbi)) return PTR_ERR(fbi); fbi->fbops = &drm_fbdev_fb_ops; fbi->screen_size = fb->height * fb->pitches[0]; fbi->fix.smem_len = fbi->screen_size; fbi->flags = FBINFO_DEFAULT; drm_fb_helper_fill_info(fbi, fb_helper, sizes); if (drm_fbdev_use_shadow_fb(fb_helper)) { fbi->screen_buffer = vzalloc(fbi->screen_size); if (!fbi->screen_buffer) return -ENOMEM; fbi->flags |= FBINFO_VIRTFB | FBINFO_READS_FAST; fbi->fbdefio = &drm_fbdev_defio; fb_deferred_io_init(fbi); } else { /* buffer is mapped for HW framebuffer */ ret = drm_client_buffer_vmap(fb_helper->buffer, &map); if (ret) return ret; if (map.is_iomem) { fbi->screen_base = map.vaddr_iomem; } else { fbi->screen_buffer = map.vaddr; fbi->flags |= FBINFO_VIRTFB; } /* * Shamelessly leak the physical address to user-space. As * page_to_phys() is undefined for I/O memory, warn in this * case. */ #if IS_ENABLED(CONFIG_DRM_FBDEV_LEAK_PHYS_SMEM) if (drm_leak_fbdev_smem && fbi->fix.smem_start == 0 && !drm_WARN_ON_ONCE(dev, map.is_iomem)) fbi->fix.smem_start = page_to_phys(virt_to_page(fbi->screen_buffer)); #endif } return 0; } static const struct drm_fb_helper_funcs drm_fb_helper_generic_funcs = { .fb_probe = drm_fb_helper_generic_probe, }; static void drm_fbdev_client_unregister(struct drm_client_dev *client) { struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client); if (fb_helper->fbdev) /* drm_fbdev_fb_destroy() takes care of cleanup */ drm_fb_helper_unregister_fbi(fb_helper); else drm_fbdev_release(fb_helper); } static int drm_fbdev_client_restore(struct drm_client_dev *client) { drm_fb_helper_lastclose(client->dev); return 0; } static int drm_fbdev_client_hotplug(struct drm_client_dev *client) { struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client); struct drm_device *dev = client->dev; int ret; /* Setup is not retried if it has failed */ if (!fb_helper->dev && fb_helper->funcs) return 0; if (dev->fb_helper) return drm_fb_helper_hotplug_event(dev->fb_helper); if (!dev->mode_config.num_connector) { drm_dbg_kms(dev, "No connectors found, will not create framebuffer!\n"); return 0; } drm_fb_helper_prepare(dev, fb_helper, &drm_fb_helper_generic_funcs); ret = drm_fb_helper_init(dev, fb_helper); if (ret) goto err; if (!drm_drv_uses_atomic_modeset(dev)) drm_helper_disable_unused_functions(dev); ret = drm_fb_helper_initial_config(fb_helper, fb_helper->preferred_bpp); if (ret) goto err_cleanup; return 0; err_cleanup: drm_fbdev_cleanup(fb_helper); err: fb_helper->dev = NULL; fb_helper->fbdev = NULL; drm_err(dev, "fbdev: Failed to setup generic emulation (ret=%d)\n", ret); return ret; } static const struct drm_client_funcs drm_fbdev_client_funcs = { .owner = THIS_MODULE, .unregister = drm_fbdev_client_unregister, .restore = drm_fbdev_client_restore, .hotplug = drm_fbdev_client_hotplug, }; /** * drm_fbdev_generic_setup() - Setup generic fbdev emulation * @dev: DRM device * @preferred_bpp: Preferred bits per pixel for the device. * @dev->mode_config.preferred_depth is used if this is zero. * * This function sets up generic fbdev emulation for drivers that supports * dumb buffers with a virtual address and that can be mmap'ed. * drm_fbdev_generic_setup() shall be called after the DRM driver registered * the new DRM device with drm_dev_register(). * * Restore, hotplug events and teardown are all taken care of. Drivers that do * suspend/resume need to call drm_fb_helper_set_suspend_unlocked() themselves. * Simple drivers might use drm_mode_config_helper_suspend(). * * Drivers that set the dirty callback on their framebuffer will get a shadow * fbdev buffer that is blitted onto the real buffer. This is done in order to * make deferred I/O work with all kinds of buffers. A shadow buffer can be * requested explicitly by setting struct drm_mode_config.prefer_shadow or * struct drm_mode_config.prefer_shadow_fbdev to true beforehand. This is * required to use generic fbdev emulation with SHMEM helpers. * * This function is safe to call even when there are no connectors present. * Setup will be retried on the next hotplug event. * * The fbdev is destroyed by drm_dev_unregister(). */ void drm_fbdev_generic_setup(struct drm_device *dev, unsigned int preferred_bpp) { struct drm_fb_helper *fb_helper; int ret; drm_WARN(dev, !dev->registered, "Device has not been registered.\n"); drm_WARN(dev, dev->fb_helper, "fb_helper is already set!\n"); if (!drm_fbdev_emulation) return; fb_helper = kzalloc(sizeof(*fb_helper), GFP_KERNEL); if (!fb_helper) { drm_err(dev, "Failed to allocate fb_helper\n"); return; } ret = drm_client_init(dev, &fb_helper->client, "fbdev", &drm_fbdev_client_funcs); if (ret) { kfree(fb_helper); drm_err(dev, "Failed to register client: %d\n", ret); return; } /* * FIXME: This mixes up depth with bpp, which results in a glorious * mess, resulting in some drivers picking wrong fbdev defaults and * others wrong preferred_depth defaults. */ if (!preferred_bpp) preferred_bpp = dev->mode_config.preferred_depth; if (!preferred_bpp) preferred_bpp = 32; fb_helper->preferred_bpp = preferred_bpp; ret = drm_fbdev_client_hotplug(&fb_helper->client); if (ret) drm_dbg_kms(dev, "client hotplug ret=%d\n", ret); drm_client_register(&fb_helper->client); } EXPORT_SYMBOL(drm_fbdev_generic_setup);