diff options
Diffstat (limited to 'drivers/gpu/drm/drm_fb_helper.c')
| -rw-r--r-- | drivers/gpu/drm/drm_fb_helper.c | 2639 |
1 files changed, 2639 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c new file mode 100644 index 000000000..442746d97 --- /dev/null +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -0,0 +1,2639 @@ +/* + * Copyright (c) 2006-2009 Red Hat Inc. + * Copyright (c) 2006-2008 Intel Corporation + * Copyright (c) 2007 Dave Airlie <airlied@linux.ie> + * + * 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 <airlied@linux.ie> + * Jesse Barnes <jesse.barnes@intel.com> + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/console.h> +#include <linux/dma-buf.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/sysrq.h> +#include <linux/vmalloc.h> + +#include <drm/drm_atomic.h> +#include <drm/drm_crtc.h> +#include <drm/drm_crtc_helper.h> +#include <drm/drm_drv.h> +#include <drm/drm_fb_helper.h> +#include <drm/drm_fourcc.h> +#include <drm/drm_framebuffer.h> +#include <drm/drm_print.h> +#include <drm/drm_vblank.h> + +#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 iosys_map *dst) +{ + struct drm_framebuffer *fb = fb_helper->fb; + size_t offset = clip->y1 * fb->pitches[0]; + size_t len = clip->x2 - clip->x1; + unsigned int y; + void *src; + + switch (drm_format_info_bpp(fb->format, 0)) { + case 1: + offset += clip->x1 / 8; + len = DIV_ROUND_UP(len + clip->x1 % 8, 8); + break; + case 2: + offset += clip->x1 / 4; + len = DIV_ROUND_UP(len + clip->x1 % 4, 4); + break; + case 4: + offset += clip->x1 / 2; + len = DIV_ROUND_UP(len + clip->x1 % 2, 2); + break; + default: + offset += clip->x1 * fb->format->cpp[0]; + len *= fb->format->cpp[0]; + break; + } + + src = fb_helper->fbdev->screen_buffer + offset; + iosys_map_incr(dst, offset); /* go to first pixel within clip rect */ + + for (y = clip->y1; y < clip->y2; y++) { + iosys_map_memcpy_to(dst, 0, src, len); + iosys_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 iosys_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); +} + +/* + * Convert memory region into area of scanlines and pixels per + * scanline. The parameters off and len must not reach beyond + * the end of the framebuffer. + */ +static void drm_fb_helper_memory_range_to_clip(struct fb_info *info, off_t off, size_t len, + struct drm_rect *clip) +{ + u32 line_length = info->fix.line_length; + u32 fb_height = info->var.yres; + off_t end = off + len; + u32 x1 = 0; + u32 y1 = off / line_length; + u32 x2 = info->var.xres; + u32 y2 = DIV_ROUND_UP(end, line_length); + + /* Don't allow any of them beyond the bottom bound of display area */ + if (y1 > fb_height) + y1 = fb_height; + if (y2 > fb_height) + y2 = fb_height; + + if ((y2 - y1) == 1) { + /* + * We've only written to a single scanline. Try to reduce + * the number of horizontal pixels that need an update. + */ + off_t bit_off = (off % line_length) * 8; + off_t bit_end = (end % line_length) * 8; + + x1 = bit_off / info->var.bits_per_pixel; + x2 = DIV_ROUND_UP(bit_end, info->var.bits_per_pixel); + } + + drm_rect_init(clip, x1, y1, x2 - x1, y2 - y1); +} + +/** + * drm_fb_helper_deferred_io() - fbdev deferred_io callback function + * @info: fb_info struct pointer + * @pagereflist: 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 *pagereflist) +{ + unsigned long start, end, min_off, max_off; + struct fb_deferred_io_pageref *pageref; + struct drm_rect damage_area; + + min_off = ULONG_MAX; + max_off = 0; + list_for_each_entry(pageref, pagereflist, list) { + start = pageref->offset; + end = start + PAGE_SIZE; + min_off = min(min_off, start); + max_off = max(max_off, end); + } + if (min_off >= max_off) + return; + + /* + * As we can only track pages, we might reach beyond the end + * of the screen and account for non-existing scanlines. Hence, + * keep the covered memory area within the screen buffer. + */ + max_off = min(max_off, info->screen_size); + + drm_fb_helper_memory_range_to_clip(info, min_off, max_off - min_off, &damage_area); + drm_fb_helper_damage(info, damage_area.x1, damage_area.y1, + drm_rect_width(&damage_area), + drm_rect_height(&damage_area)); +} +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) +{ + loff_t pos = *ppos; + ssize_t ret; + struct drm_rect damage_area; + + ret = fb_sys_write(info, buf, count, ppos); + if (ret <= 0) + return ret; + + drm_fb_helper_memory_range_to_clip(info, pos, ret, &damage_area); + drm_fb_helper_damage(info, damage_area.x1, damage_area.y1, + drm_rect_width(&damage_area), + drm_rect_height(&damage_area)); + + 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, + const struct drm_format_info *format) +{ + u8 depth = format->depth; + + if (format->is_color_indexed) { + var->red.offset = 0; + var->green.offset = 0; + var->blue.offset = 0; + var->red.length = depth; + var->green.length = depth; + var->blue.length = depth; + var->transp.offset = 0; + var->transp.length = 0; + return; + } + + switch (depth) { + 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; + const struct drm_format_info *format = fb->format; + struct drm_device *dev = fb_helper->dev; + unsigned int bpp; + + 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; + } + + switch (format->format) { + case DRM_FORMAT_C1: + case DRM_FORMAT_C2: + case DRM_FORMAT_C4: + /* supported format with sub-byte pixels */ + break; + + default: + if ((drm_format_info_block_width(format, 0) > 1) || + (drm_format_info_block_height(format, 0) > 1)) + return -EINVAL; + break; + } + + /* + * Changes struct fb_var_screeninfo are currently not pushed back + * to KMS, hence fail if different settings are requested. + */ + bpp = drm_format_info_bpp(format, 0); + if (var->bits_per_pixel > bpp || + 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, bpp); + 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, format); + } + + /* + * Likewise, bits_per_pixel should be rounded up to a supported value. + */ + var->bits_per_pixel = bpp; + + /* + * 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, + bool is_color_indexed) +{ + info->fix.type = FB_TYPE_PACKED_PIXELS; + info->fix.visual = is_color_indexed ? 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; + const struct drm_format_info *format = fb->format; + + switch (format->format) { + case DRM_FORMAT_C1: + case DRM_FORMAT_C2: + case DRM_FORMAT_C4: + /* supported format with sub-byte pixels */ + break; + + default: + WARN_ON((drm_format_info_block_width(format, 0) > 1) || + (drm_format_info_block_height(format, 0) > 1)); + break; + } + + info->pseudo_palette = fb_helper->pseudo_palette; + info->var.xres_virtual = fb->width; + info->var.yres_virtual = fb->height; + info->var.bits_per_pixel = drm_format_info_bpp(format, 0); + 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, format); + + 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->is_color_indexed); + 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 (drm_fbdev_use_shadow_fb(fb_helper)) + return fb_deferred_io_mmap(info, vma); + else 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; + struct drm_rect damage_area; + 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) + return ret; /* return last error, if any */ + else if (!ret) + return err; /* return previous error, if any */ + + *ppos += ret; + + drm_fb_helper_memory_range_to_clip(info, pos, ret, &damage_area); + drm_fb_helper_damage(info, damage_area.x1, damage_area.y1, + drm_rect_width(&damage_area), + drm_rect_height(&damage_area)); + + return ret; +} + +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 iosys_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 = sizes->surface_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; + + drm_client_register(&fb_helper->client); +} +EXPORT_SYMBOL(drm_fbdev_generic_setup); |