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1// SPDX-License-Identifier: GPL-2.0 or MIT2/*3 * Copyright 2018 Noralf Trønnes4 */5 6#include <linux/iosys-map.h>7#include <linux/list.h>8#include <linux/mutex.h>9#include <linux/seq_file.h>10#include <linux/slab.h>11 12#include <drm/drm_client.h>13#include <drm/drm_debugfs.h>14#include <drm/drm_device.h>15#include <drm/drm_drv.h>16#include <drm/drm_file.h>17#include <drm/drm_fourcc.h>18#include <drm/drm_framebuffer.h>19#include <drm/drm_gem.h>20#include <drm/drm_mode.h>21#include <drm/drm_print.h>22 23#include "drm_crtc_internal.h"24#include "drm_internal.h"25 26/**27 * DOC: overview28 *29 * This library provides support for clients running in the kernel like fbdev and bootsplash.30 *31 * GEM drivers which provide a GEM based dumb buffer with a virtual address are supported.32 */33 34static int drm_client_open(struct drm_client_dev *client)35{36 struct drm_device *dev = client->dev;37 struct drm_file *file;38 39 file = drm_file_alloc(dev->primary);40 if (IS_ERR(file))41 return PTR_ERR(file);42 43 mutex_lock(&dev->filelist_mutex);44 list_add(&file->lhead, &dev->filelist_internal);45 mutex_unlock(&dev->filelist_mutex);46 47 client->file = file;48 49 return 0;50}51 52static void drm_client_close(struct drm_client_dev *client)53{54 struct drm_device *dev = client->dev;55 56 mutex_lock(&dev->filelist_mutex);57 list_del(&client->file->lhead);58 mutex_unlock(&dev->filelist_mutex);59 60 drm_file_free(client->file);61}62 63/**64 * drm_client_init - Initialise a DRM client65 * @dev: DRM device66 * @client: DRM client67 * @name: Client name68 * @funcs: DRM client functions (optional)69 *70 * This initialises the client and opens a &drm_file.71 * Use drm_client_register() to complete the process.72 * The caller needs to hold a reference on @dev before calling this function.73 * The client is freed when the &drm_device is unregistered. See drm_client_release().74 *75 * Returns:76 * Zero on success or negative error code on failure.77 */78int drm_client_init(struct drm_device *dev, struct drm_client_dev *client,79 const char *name, const struct drm_client_funcs *funcs)80{81 int ret;82 83 if (!drm_core_check_feature(dev, DRIVER_MODESET) || !dev->driver->dumb_create)84 return -EOPNOTSUPP;85 86 client->dev = dev;87 client->name = name;88 client->funcs = funcs;89 90 ret = drm_client_modeset_create(client);91 if (ret)92 return ret;93 94 ret = drm_client_open(client);95 if (ret)96 goto err_free;97 98 drm_dev_get(dev);99 100 return 0;101 102err_free:103 drm_client_modeset_free(client);104 return ret;105}106EXPORT_SYMBOL(drm_client_init);107 108/**109 * drm_client_register - Register client110 * @client: DRM client111 *112 * Add the client to the &drm_device client list to activate its callbacks.113 * @client must be initialized by a call to drm_client_init(). After114 * drm_client_register() it is no longer permissible to call drm_client_release()115 * directly (outside the unregister callback), instead cleanup will happen116 * automatically on driver unload.117 *118 * Registering a client generates a hotplug event that allows the client119 * to set up its display from pre-existing outputs. The client must have120 * initialized its state to able to handle the hotplug event successfully.121 */122void drm_client_register(struct drm_client_dev *client)123{124 struct drm_device *dev = client->dev;125 int ret;126 127 mutex_lock(&dev->clientlist_mutex);128 list_add(&client->list, &dev->clientlist);129 130 if (client->funcs && client->funcs->hotplug) {131 /*132 * Perform an initial hotplug event to pick up the133 * display configuration for the client. This step134 * has to be performed *after* registering the client135 * in the list of clients, or a concurrent hotplug136 * event might be lost; leaving the display off.137 *138 * Hold the clientlist_mutex as for a regular hotplug139 * event.140 */141 ret = client->funcs->hotplug(client);142 if (ret)143 drm_dbg_kms(dev, "client hotplug ret=%d\n", ret);144 }145 mutex_unlock(&dev->clientlist_mutex);146}147EXPORT_SYMBOL(drm_client_register);148 149/**150 * drm_client_release - Release DRM client resources151 * @client: DRM client152 *153 * Releases resources by closing the &drm_file that was opened by drm_client_init().154 * It is called automatically if the &drm_client_funcs.unregister callback is _not_ set.155 *156 * This function should only be called from the unregister callback. An exception157 * is fbdev which cannot free the buffer if userspace has open file descriptors.158 *159 * Note:160 * Clients cannot initiate a release by themselves. This is done to keep the code simple.161 * The driver has to be unloaded before the client can be unloaded.162 */163void drm_client_release(struct drm_client_dev *client)164{165 struct drm_device *dev = client->dev;166 167 drm_dbg_kms(dev, "%s\n", client->name);168 169 drm_client_modeset_free(client);170 drm_client_close(client);171 drm_dev_put(dev);172}173EXPORT_SYMBOL(drm_client_release);174 175/**176 * drm_client_dev_unregister - Unregister clients177 * @dev: DRM device178 *179 * This function releases all clients by calling each client's180 * &drm_client_funcs.unregister callback. The callback function181 * is responsibe for releaseing all resources including the client182 * itself.183 *184 * The helper drm_dev_unregister() calls this function. Drivers185 * that use it don't need to call this function themselves.186 */187void drm_client_dev_unregister(struct drm_device *dev)188{189 struct drm_client_dev *client, *tmp;190 191 if (!drm_core_check_feature(dev, DRIVER_MODESET))192 return;193 194 mutex_lock(&dev->clientlist_mutex);195 list_for_each_entry_safe(client, tmp, &dev->clientlist, list) {196 list_del(&client->list);197 if (client->funcs && client->funcs->unregister) {198 client->funcs->unregister(client);199 } else {200 drm_client_release(client);201 kfree(client);202 }203 }204 mutex_unlock(&dev->clientlist_mutex);205}206EXPORT_SYMBOL(drm_client_dev_unregister);207 208/**209 * drm_client_dev_hotplug - Send hotplug event to clients210 * @dev: DRM device211 *212 * This function calls the &drm_client_funcs.hotplug callback on the attached clients.213 *214 * drm_kms_helper_hotplug_event() calls this function, so drivers that use it215 * don't need to call this function themselves.216 */217void drm_client_dev_hotplug(struct drm_device *dev)218{219 struct drm_client_dev *client;220 int ret;221 222 if (!drm_core_check_feature(dev, DRIVER_MODESET))223 return;224 225 if (!dev->mode_config.num_connector) {226 drm_dbg_kms(dev, "No connectors found, will not send hotplug events!\n");227 return;228 }229 230 mutex_lock(&dev->clientlist_mutex);231 list_for_each_entry(client, &dev->clientlist, list) {232 if (!client->funcs || !client->funcs->hotplug)233 continue;234 235 if (client->hotplug_failed)236 continue;237 238 ret = client->funcs->hotplug(client);239 drm_dbg_kms(dev, "%s: ret=%d\n", client->name, ret);240 if (ret)241 client->hotplug_failed = true;242 }243 mutex_unlock(&dev->clientlist_mutex);244}245EXPORT_SYMBOL(drm_client_dev_hotplug);246 247void drm_client_dev_restore(struct drm_device *dev)248{249 struct drm_client_dev *client;250 int ret;251 252 if (!drm_core_check_feature(dev, DRIVER_MODESET))253 return;254 255 mutex_lock(&dev->clientlist_mutex);256 list_for_each_entry(client, &dev->clientlist, list) {257 if (!client->funcs || !client->funcs->restore)258 continue;259 260 ret = client->funcs->restore(client);261 drm_dbg_kms(dev, "%s: ret=%d\n", client->name, ret);262 if (!ret) /* The first one to return zero gets the privilege to restore */263 break;264 }265 mutex_unlock(&dev->clientlist_mutex);266}267 268static void drm_client_buffer_delete(struct drm_client_buffer *buffer)269{270 if (buffer->gem) {271 drm_gem_vunmap_unlocked(buffer->gem, &buffer->map);272 drm_gem_object_put(buffer->gem);273 }274 275 kfree(buffer);276}277 278static struct drm_client_buffer *279drm_client_buffer_create(struct drm_client_dev *client, u32 width, u32 height,280 u32 format, u32 *handle)281{282 const struct drm_format_info *info = drm_format_info(format);283 struct drm_mode_create_dumb dumb_args = { };284 struct drm_device *dev = client->dev;285 struct drm_client_buffer *buffer;286 struct drm_gem_object *obj;287 int ret;288 289 buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);290 if (!buffer)291 return ERR_PTR(-ENOMEM);292 293 buffer->client = client;294 295 dumb_args.width = width;296 dumb_args.height = height;297 dumb_args.bpp = drm_format_info_bpp(info, 0);298 ret = drm_mode_create_dumb(dev, &dumb_args, client->file);299 if (ret)300 goto err_delete;301 302 obj = drm_gem_object_lookup(client->file, dumb_args.handle);303 if (!obj) {304 ret = -ENOENT;305 goto err_delete;306 }307 308 buffer->pitch = dumb_args.pitch;309 buffer->gem = obj;310 *handle = dumb_args.handle;311 312 return buffer;313 314err_delete:315 drm_client_buffer_delete(buffer);316 317 return ERR_PTR(ret);318}319 320/**321 * drm_client_buffer_vmap_local - Map DRM client buffer into address space322 * @buffer: DRM client buffer323 * @map_copy: Returns the mapped memory's address324 *325 * This function maps a client buffer into kernel address space. If the326 * buffer is already mapped, it returns the existing mapping's address.327 *328 * Client buffer mappings are not ref'counted. Each call to329 * drm_client_buffer_vmap_local() should be closely followed by a call to330 * drm_client_buffer_vunmap_local(). See drm_client_buffer_vmap() for331 * long-term mappings.332 *333 * The returned address is a copy of the internal value. In contrast to334 * other vmap interfaces, you don't need it for the client's vunmap335 * function. So you can modify it at will during blit and draw operations.336 *337 * Returns:338 * 0 on success, or a negative errno code otherwise.339 */340int drm_client_buffer_vmap_local(struct drm_client_buffer *buffer,341 struct iosys_map *map_copy)342{343 struct drm_gem_object *gem = buffer->gem;344 struct iosys_map *map = &buffer->map;345 int ret;346 347 drm_gem_lock(gem);348 349 ret = drm_gem_vmap(gem, map);350 if (ret)351 goto err_drm_gem_vmap_unlocked;352 *map_copy = *map;353 354 return 0;355 356err_drm_gem_vmap_unlocked:357 drm_gem_unlock(gem);358 return ret;359}360EXPORT_SYMBOL(drm_client_buffer_vmap_local);361 362/**363 * drm_client_buffer_vunmap_local - Unmap DRM client buffer364 * @buffer: DRM client buffer365 *366 * This function removes a client buffer's memory mapping established367 * with drm_client_buffer_vunmap_local(). Calling this function is only368 * required by clients that manage their buffer mappings by themselves.369 */370void drm_client_buffer_vunmap_local(struct drm_client_buffer *buffer)371{372 struct drm_gem_object *gem = buffer->gem;373 struct iosys_map *map = &buffer->map;374 375 drm_gem_vunmap(gem, map);376 drm_gem_unlock(gem);377}378EXPORT_SYMBOL(drm_client_buffer_vunmap_local);379 380/**381 * drm_client_buffer_vmap - Map DRM client buffer into address space382 * @buffer: DRM client buffer383 * @map_copy: Returns the mapped memory's address384 *385 * This function maps a client buffer into kernel address space. If the386 * buffer is already mapped, it returns the existing mapping's address.387 *388 * Client buffer mappings are not ref'counted. Each call to389 * drm_client_buffer_vmap() should be followed by a call to390 * drm_client_buffer_vunmap(); or the client buffer should be mapped391 * throughout its lifetime.392 *393 * The returned address is a copy of the internal value. In contrast to394 * other vmap interfaces, you don't need it for the client's vunmap395 * function. So you can modify it at will during blit and draw operations.396 *397 * Returns:398 * 0 on success, or a negative errno code otherwise.399 */400int401drm_client_buffer_vmap(struct drm_client_buffer *buffer,402 struct iosys_map *map_copy)403{404 struct drm_gem_object *gem = buffer->gem;405 struct iosys_map *map = &buffer->map;406 int ret;407 408 drm_gem_lock(gem);409 410 ret = drm_gem_pin_locked(gem);411 if (ret)412 goto err_drm_gem_pin_locked;413 ret = drm_gem_vmap(gem, map);414 if (ret)415 goto err_drm_gem_vmap;416 417 drm_gem_unlock(gem);418 419 *map_copy = *map;420 421 return 0;422 423err_drm_gem_vmap:424 drm_gem_unpin_locked(buffer->gem);425err_drm_gem_pin_locked:426 drm_gem_unlock(gem);427 return ret;428}429EXPORT_SYMBOL(drm_client_buffer_vmap);430 431/**432 * drm_client_buffer_vunmap - Unmap DRM client buffer433 * @buffer: DRM client buffer434 *435 * This function removes a client buffer's memory mapping. Calling this436 * function is only required by clients that manage their buffer mappings437 * by themselves.438 */439void drm_client_buffer_vunmap(struct drm_client_buffer *buffer)440{441 struct drm_gem_object *gem = buffer->gem;442 struct iosys_map *map = &buffer->map;443 444 drm_gem_lock(gem);445 drm_gem_vunmap(gem, map);446 drm_gem_unpin_locked(gem);447 drm_gem_unlock(gem);448}449EXPORT_SYMBOL(drm_client_buffer_vunmap);450 451static void drm_client_buffer_rmfb(struct drm_client_buffer *buffer)452{453 int ret;454 455 if (!buffer->fb)456 return;457 458 ret = drm_mode_rmfb(buffer->client->dev, buffer->fb->base.id, buffer->client->file);459 if (ret)460 drm_err(buffer->client->dev,461 "Error removing FB:%u (%d)\n", buffer->fb->base.id, ret);462 463 buffer->fb = NULL;464}465 466static int drm_client_buffer_addfb(struct drm_client_buffer *buffer,467 u32 width, u32 height, u32 format,468 u32 handle)469{470 struct drm_client_dev *client = buffer->client;471 struct drm_mode_fb_cmd2 fb_req = { };472 int ret;473 474 fb_req.width = width;475 fb_req.height = height;476 fb_req.pixel_format = format;477 fb_req.handles[0] = handle;478 fb_req.pitches[0] = buffer->pitch;479 480 ret = drm_mode_addfb2(client->dev, &fb_req, client->file);481 if (ret)482 return ret;483 484 buffer->fb = drm_framebuffer_lookup(client->dev, buffer->client->file, fb_req.fb_id);485 if (WARN_ON(!buffer->fb))486 return -ENOENT;487 488 /* drop the reference we picked up in framebuffer lookup */489 drm_framebuffer_put(buffer->fb);490 491 strscpy(buffer->fb->comm, client->name, TASK_COMM_LEN);492 493 return 0;494}495 496/**497 * drm_client_framebuffer_create - Create a client framebuffer498 * @client: DRM client499 * @width: Framebuffer width500 * @height: Framebuffer height501 * @format: Buffer format502 *503 * This function creates a &drm_client_buffer which consists of a504 * &drm_framebuffer backed by a dumb buffer.505 * Call drm_client_framebuffer_delete() to free the buffer.506 *507 * Returns:508 * Pointer to a client buffer or an error pointer on failure.509 */510struct drm_client_buffer *511drm_client_framebuffer_create(struct drm_client_dev *client, u32 width, u32 height, u32 format)512{513 struct drm_client_buffer *buffer;514 u32 handle;515 int ret;516 517 buffer = drm_client_buffer_create(client, width, height, format,518 &handle);519 if (IS_ERR(buffer))520 return buffer;521 522 ret = drm_client_buffer_addfb(buffer, width, height, format, handle);523 524 /*525 * The handle is only needed for creating the framebuffer, destroy it526 * again to solve a circular dependency should anybody export the GEM527 * object as DMA-buf. The framebuffer and our buffer structure are still528 * holding references to the GEM object to prevent its destruction.529 */530 drm_mode_destroy_dumb(client->dev, handle, client->file);531 532 if (ret) {533 drm_client_buffer_delete(buffer);534 return ERR_PTR(ret);535 }536 537 return buffer;538}539EXPORT_SYMBOL(drm_client_framebuffer_create);540 541/**542 * drm_client_framebuffer_delete - Delete a client framebuffer543 * @buffer: DRM client buffer (can be NULL)544 */545void drm_client_framebuffer_delete(struct drm_client_buffer *buffer)546{547 if (!buffer)548 return;549 550 drm_client_buffer_rmfb(buffer);551 drm_client_buffer_delete(buffer);552}553EXPORT_SYMBOL(drm_client_framebuffer_delete);554 555/**556 * drm_client_framebuffer_flush - Manually flush client framebuffer557 * @buffer: DRM client buffer (can be NULL)558 * @rect: Damage rectangle (if NULL flushes all)559 *560 * This calls &drm_framebuffer_funcs->dirty (if present) to flush buffer changes561 * for drivers that need it.562 *563 * Returns:564 * Zero on success or negative error code on failure.565 */566int drm_client_framebuffer_flush(struct drm_client_buffer *buffer, struct drm_rect *rect)567{568 if (!buffer || !buffer->fb || !buffer->fb->funcs->dirty)569 return 0;570 571 if (rect) {572 struct drm_clip_rect clip = {573 .x1 = rect->x1,574 .y1 = rect->y1,575 .x2 = rect->x2,576 .y2 = rect->y2,577 };578 579 return buffer->fb->funcs->dirty(buffer->fb, buffer->client->file,580 0, 0, &clip, 1);581 }582 583 return buffer->fb->funcs->dirty(buffer->fb, buffer->client->file,584 0, 0, NULL, 0);585}586EXPORT_SYMBOL(drm_client_framebuffer_flush);587 588#ifdef CONFIG_DEBUG_FS589static int drm_client_debugfs_internal_clients(struct seq_file *m, void *data)590{591 struct drm_debugfs_entry *entry = m->private;592 struct drm_device *dev = entry->dev;593 struct drm_printer p = drm_seq_file_printer(m);594 struct drm_client_dev *client;595 596 mutex_lock(&dev->clientlist_mutex);597 list_for_each_entry(client, &dev->clientlist, list)598 drm_printf(&p, "%s\n", client->name);599 mutex_unlock(&dev->clientlist_mutex);600 601 return 0;602}603 604static const struct drm_debugfs_info drm_client_debugfs_list[] = {605 { "internal_clients", drm_client_debugfs_internal_clients, 0 },606};607 608void drm_client_debugfs_init(struct drm_device *dev)609{610 drm_debugfs_add_files(dev, drm_client_debugfs_list,611 ARRAY_SIZE(drm_client_debugfs_list));612}613#endif614