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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 | // SPDX-License-Identifier: GPL-2.0 /* * Copyright 2022 HabanaLabs, Ltd. * All Rights Reserved. * */ #include <linux/debugfs.h> #include <linux/device.h> #include <linux/idr.h> #include <drm/drm_accel.h> #include <drm/drm_auth.h> #include <drm/drm_debugfs.h> #include <drm/drm_drv.h> #include <drm/drm_file.h> #include <drm/drm_ioctl.h> #include <drm/drm_print.h> static DEFINE_SPINLOCK(accel_minor_lock); static struct idr accel_minors_idr; static struct dentry *accel_debugfs_root; static struct device_type accel_sysfs_device_minor = { .name = "accel_minor" }; static char *accel_devnode(const struct device *dev, umode_t *mode) { return kasprintf(GFP_KERNEL, "accel/%s", dev_name(dev)); } static const struct class accel_class = { .name = "accel", .devnode = accel_devnode, }; static int accel_sysfs_init(void) { return class_register(&accel_class); } static void accel_sysfs_destroy(void) { class_unregister(&accel_class); } static int accel_name_info(struct seq_file *m, void *data) { struct drm_info_node *node = (struct drm_info_node *) m->private; struct drm_minor *minor = node->minor; struct drm_device *dev = minor->dev; struct drm_master *master; mutex_lock(&dev->master_mutex); master = dev->master; seq_printf(m, "%s", dev->driver->name); if (dev->dev) seq_printf(m, " dev=%s", dev_name(dev->dev)); if (master && master->unique) seq_printf(m, " master=%s", master->unique); if (dev->unique) seq_printf(m, " unique=%s", dev->unique); seq_puts(m, "\n"); mutex_unlock(&dev->master_mutex); return 0; } static const struct drm_info_list accel_debugfs_list[] = { {"name", accel_name_info, 0} }; #define ACCEL_DEBUGFS_ENTRIES ARRAY_SIZE(accel_debugfs_list) /** * accel_debugfs_init() - Initialize debugfs for device * @dev: Pointer to the device instance. * * This function creates a root directory for the device in debugfs. */ void accel_debugfs_init(struct drm_device *dev) { drm_debugfs_dev_init(dev, accel_debugfs_root); } /** * accel_debugfs_register() - Register debugfs for device * @dev: Pointer to the device instance. * * Creates common files for accelerators. */ void accel_debugfs_register(struct drm_device *dev) { struct drm_minor *minor = dev->accel; minor->debugfs_root = dev->debugfs_root; drm_debugfs_create_files(accel_debugfs_list, ACCEL_DEBUGFS_ENTRIES, dev->debugfs_root, minor); } /** * accel_set_device_instance_params() - Set some device parameters for accel device * @kdev: Pointer to the device instance. * @index: The minor's index * * This function creates the dev_t of the device using the accel major and * the device's minor number. In addition, it sets the class and type of the * device instance to the accel sysfs class and device type, respectively. */ void accel_set_device_instance_params(struct device *kdev, int index) { kdev->devt = MKDEV(ACCEL_MAJOR, index); kdev->class = &accel_class; kdev->type = &accel_sysfs_device_minor; } /** * accel_minor_alloc() - Allocates a new accel minor * * This function access the accel minors idr and allocates from it * a new id to represent a new accel minor * * Return: A new id on success or error code in case idr_alloc failed */ int accel_minor_alloc(void) { unsigned long flags; int r; spin_lock_irqsave(&accel_minor_lock, flags); r = idr_alloc(&accel_minors_idr, NULL, 0, ACCEL_MAX_MINORS, GFP_NOWAIT); spin_unlock_irqrestore(&accel_minor_lock, flags); return r; } /** * accel_minor_remove() - Remove an accel minor * @index: The minor id to remove. * * This function access the accel minors idr and removes from * it the member with the id that is passed to this function. */ void accel_minor_remove(int index) { unsigned long flags; spin_lock_irqsave(&accel_minor_lock, flags); idr_remove(&accel_minors_idr, index); spin_unlock_irqrestore(&accel_minor_lock, flags); } /** * accel_minor_replace() - Replace minor pointer in accel minors idr. * @minor: Pointer to the new minor. * @index: The minor id to replace. * * This function access the accel minors idr structure and replaces the pointer * that is associated with an existing id. Because the minor pointer can be * NULL, we need to explicitly pass the index. * * Return: 0 for success, negative value for error */ void accel_minor_replace(struct drm_minor *minor, int index) { unsigned long flags; spin_lock_irqsave(&accel_minor_lock, flags); idr_replace(&accel_minors_idr, minor, index); spin_unlock_irqrestore(&accel_minor_lock, flags); } /* * Looks up the given minor-ID and returns the respective DRM-minor object. The * refence-count of the underlying device is increased so you must release this * object with accel_minor_release(). * * The object can be only a drm_minor that represents an accel device. * * As long as you hold this minor, it is guaranteed that the object and the * minor->dev pointer will stay valid! However, the device may get unplugged and * unregistered while you hold the minor. */ static struct drm_minor *accel_minor_acquire(unsigned int minor_id) { struct drm_minor *minor; unsigned long flags; spin_lock_irqsave(&accel_minor_lock, flags); minor = idr_find(&accel_minors_idr, minor_id); if (minor) drm_dev_get(minor->dev); spin_unlock_irqrestore(&accel_minor_lock, flags); if (!minor) { return ERR_PTR(-ENODEV); } else if (drm_dev_is_unplugged(minor->dev)) { drm_dev_put(minor->dev); return ERR_PTR(-ENODEV); } return minor; } static void accel_minor_release(struct drm_minor *minor) { drm_dev_put(minor->dev); } /** * accel_open - open method for ACCEL file * @inode: device inode * @filp: file pointer. * * This function must be used by drivers as their &file_operations.open method. * It looks up the correct ACCEL device and instantiates all the per-file * resources for it. It also calls the &drm_driver.open driver callback. * * Return: 0 on success or negative errno value on failure. */ int accel_open(struct inode *inode, struct file *filp) { struct drm_device *dev; struct drm_minor *minor; int retcode; minor = accel_minor_acquire(iminor(inode)); if (IS_ERR(minor)) return PTR_ERR(minor); dev = minor->dev; atomic_fetch_inc(&dev->open_count); /* share address_space across all char-devs of a single device */ filp->f_mapping = dev->anon_inode->i_mapping; retcode = drm_open_helper(filp, minor); if (retcode) goto err_undo; return 0; err_undo: atomic_dec(&dev->open_count); accel_minor_release(minor); return retcode; } EXPORT_SYMBOL_GPL(accel_open); static int accel_stub_open(struct inode *inode, struct file *filp) { const struct file_operations *new_fops; struct drm_minor *minor; int err; minor = accel_minor_acquire(iminor(inode)); if (IS_ERR(minor)) return PTR_ERR(minor); new_fops = fops_get(minor->dev->driver->fops); if (!new_fops) { err = -ENODEV; goto out; } replace_fops(filp, new_fops); if (filp->f_op->open) err = filp->f_op->open(inode, filp); else err = 0; out: accel_minor_release(minor); return err; } static const struct file_operations accel_stub_fops = { .owner = THIS_MODULE, .open = accel_stub_open, .llseek = noop_llseek, }; void accel_core_exit(void) { unregister_chrdev(ACCEL_MAJOR, "accel"); debugfs_remove(accel_debugfs_root); accel_sysfs_destroy(); idr_destroy(&accel_minors_idr); } int __init accel_core_init(void) { int ret; idr_init(&accel_minors_idr); ret = accel_sysfs_init(); if (ret < 0) { DRM_ERROR("Cannot create ACCEL class: %d\n", ret); goto error; } accel_debugfs_root = debugfs_create_dir("accel", NULL); ret = register_chrdev(ACCEL_MAJOR, "accel", &accel_stub_fops); if (ret < 0) DRM_ERROR("Cannot register ACCEL major: %d\n", ret); error: /* * Any cleanup due to errors will be done in drm_core_exit() that * will call accel_core_exit() */ return ret; } |