1 /* 2 * FPGA Manager Core 3 * 4 * Copyright (C) 2013-2015 Altera Corporation 5 * 6 * With code from the mailing list: 7 * Copyright (C) 2013 Xilinx, Inc. 8 * 9 * This program is free software; you can redistribute it and/or modify it 10 * under the terms and conditions of the GNU General Public License, 11 * version 2, as published by the Free Software Foundation. 12 * 13 * This program is distributed in the hope it will be useful, but WITHOUT 14 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 15 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 16 * more details. 17 * 18 * You should have received a copy of the GNU General Public License along with 19 * this program. If not, see <http://www.gnu.org/licenses/>. 20 */ 21 #include <linux/firmware.h> 22 #include <linux/fpga/fpga-mgr.h> 23 #include <linux/idr.h> 24 #include <linux/module.h> 25 #include <linux/of.h> 26 #include <linux/mutex.h> 27 #include <linux/slab.h> 28 29 static DEFINE_IDA(fpga_mgr_ida); 30 static struct class *fpga_mgr_class; 31 32 /** 33 * fpga_mgr_buf_load - load fpga from image in buffer 34 * @mgr: fpga manager 35 * @info: fpga image specific information 36 * @buf: buffer contain fpga image 37 * @count: byte count of buf 38 * 39 * Step the low level fpga manager through the device-specific steps of getting 40 * an FPGA ready to be configured, writing the image to it, then doing whatever 41 * post-configuration steps necessary. This code assumes the caller got the 42 * mgr pointer from of_fpga_mgr_get() or fpga_mgr_get() and checked that it is 43 * not an error code. 44 * 45 * Return: 0 on success, negative error code otherwise. 46 */ 47 int fpga_mgr_buf_load(struct fpga_manager *mgr, struct fpga_image_info *info, 48 const char *buf, size_t count) 49 { 50 struct device *dev = &mgr->dev; 51 int ret; 52 53 /* 54 * Call the low level driver's write_init function. This will do the 55 * device-specific things to get the FPGA into the state where it is 56 * ready to receive an FPGA image. The low level driver only gets to 57 * see the first initial_header_size bytes in the buffer. 58 */ 59 mgr->state = FPGA_MGR_STATE_WRITE_INIT; 60 ret = mgr->mops->write_init(mgr, info, buf, 61 min(mgr->mops->initial_header_size, count)); 62 if (ret) { 63 dev_err(dev, "Error preparing FPGA for writing\n"); 64 mgr->state = FPGA_MGR_STATE_WRITE_INIT_ERR; 65 return ret; 66 } 67 68 /* 69 * Write the FPGA image to the FPGA. 70 */ 71 mgr->state = FPGA_MGR_STATE_WRITE; 72 ret = mgr->mops->write(mgr, buf, count); 73 if (ret) { 74 dev_err(dev, "Error while writing image data to FPGA\n"); 75 mgr->state = FPGA_MGR_STATE_WRITE_ERR; 76 return ret; 77 } 78 79 /* 80 * After all the FPGA image has been written, do the device specific 81 * steps to finish and set the FPGA into operating mode. 82 */ 83 mgr->state = FPGA_MGR_STATE_WRITE_COMPLETE; 84 ret = mgr->mops->write_complete(mgr, info); 85 if (ret) { 86 dev_err(dev, "Error after writing image data to FPGA\n"); 87 mgr->state = FPGA_MGR_STATE_WRITE_COMPLETE_ERR; 88 return ret; 89 } 90 mgr->state = FPGA_MGR_STATE_OPERATING; 91 92 return 0; 93 } 94 EXPORT_SYMBOL_GPL(fpga_mgr_buf_load); 95 96 /** 97 * fpga_mgr_firmware_load - request firmware and load to fpga 98 * @mgr: fpga manager 99 * @info: fpga image specific information 100 * @image_name: name of image file on the firmware search path 101 * 102 * Request an FPGA image using the firmware class, then write out to the FPGA. 103 * Update the state before each step to provide info on what step failed if 104 * there is a failure. This code assumes the caller got the mgr pointer 105 * from of_fpga_mgr_get() or fpga_mgr_get() and checked that it is not an error 106 * code. 107 * 108 * Return: 0 on success, negative error code otherwise. 109 */ 110 int fpga_mgr_firmware_load(struct fpga_manager *mgr, 111 struct fpga_image_info *info, 112 const char *image_name) 113 { 114 struct device *dev = &mgr->dev; 115 const struct firmware *fw; 116 int ret; 117 118 dev_info(dev, "writing %s to %s\n", image_name, mgr->name); 119 120 mgr->state = FPGA_MGR_STATE_FIRMWARE_REQ; 121 122 ret = request_firmware(&fw, image_name, dev); 123 if (ret) { 124 mgr->state = FPGA_MGR_STATE_FIRMWARE_REQ_ERR; 125 dev_err(dev, "Error requesting firmware %s\n", image_name); 126 return ret; 127 } 128 129 ret = fpga_mgr_buf_load(mgr, info, fw->data, fw->size); 130 131 release_firmware(fw); 132 133 return ret; 134 } 135 EXPORT_SYMBOL_GPL(fpga_mgr_firmware_load); 136 137 static const char * const state_str[] = { 138 [FPGA_MGR_STATE_UNKNOWN] = "unknown", 139 [FPGA_MGR_STATE_POWER_OFF] = "power off", 140 [FPGA_MGR_STATE_POWER_UP] = "power up", 141 [FPGA_MGR_STATE_RESET] = "reset", 142 143 /* requesting FPGA image from firmware */ 144 [FPGA_MGR_STATE_FIRMWARE_REQ] = "firmware request", 145 [FPGA_MGR_STATE_FIRMWARE_REQ_ERR] = "firmware request error", 146 147 /* Preparing FPGA to receive image */ 148 [FPGA_MGR_STATE_WRITE_INIT] = "write init", 149 [FPGA_MGR_STATE_WRITE_INIT_ERR] = "write init error", 150 151 /* Writing image to FPGA */ 152 [FPGA_MGR_STATE_WRITE] = "write", 153 [FPGA_MGR_STATE_WRITE_ERR] = "write error", 154 155 /* Finishing configuration after image has been written */ 156 [FPGA_MGR_STATE_WRITE_COMPLETE] = "write complete", 157 [FPGA_MGR_STATE_WRITE_COMPLETE_ERR] = "write complete error", 158 159 /* FPGA reports to be in normal operating mode */ 160 [FPGA_MGR_STATE_OPERATING] = "operating", 161 }; 162 163 static ssize_t name_show(struct device *dev, 164 struct device_attribute *attr, char *buf) 165 { 166 struct fpga_manager *mgr = to_fpga_manager(dev); 167 168 return sprintf(buf, "%s\n", mgr->name); 169 } 170 171 static ssize_t state_show(struct device *dev, 172 struct device_attribute *attr, char *buf) 173 { 174 struct fpga_manager *mgr = to_fpga_manager(dev); 175 176 return sprintf(buf, "%s\n", state_str[mgr->state]); 177 } 178 179 static DEVICE_ATTR_RO(name); 180 static DEVICE_ATTR_RO(state); 181 182 static struct attribute *fpga_mgr_attrs[] = { 183 &dev_attr_name.attr, 184 &dev_attr_state.attr, 185 NULL, 186 }; 187 ATTRIBUTE_GROUPS(fpga_mgr); 188 189 struct fpga_manager *__fpga_mgr_get(struct device *dev) 190 { 191 struct fpga_manager *mgr; 192 int ret = -ENODEV; 193 194 mgr = to_fpga_manager(dev); 195 if (!mgr) 196 goto err_dev; 197 198 /* Get exclusive use of fpga manager */ 199 if (!mutex_trylock(&mgr->ref_mutex)) { 200 ret = -EBUSY; 201 goto err_dev; 202 } 203 204 if (!try_module_get(dev->parent->driver->owner)) 205 goto err_ll_mod; 206 207 return mgr; 208 209 err_ll_mod: 210 mutex_unlock(&mgr->ref_mutex); 211 err_dev: 212 put_device(dev); 213 return ERR_PTR(ret); 214 } 215 216 static int fpga_mgr_dev_match(struct device *dev, const void *data) 217 { 218 return dev->parent == data; 219 } 220 221 /** 222 * fpga_mgr_get - get an exclusive reference to a fpga mgr 223 * @dev: parent device that fpga mgr was registered with 224 * 225 * Given a device, get an exclusive reference to a fpga mgr. 226 * 227 * Return: fpga manager struct or IS_ERR() condition containing error code. 228 */ 229 struct fpga_manager *fpga_mgr_get(struct device *dev) 230 { 231 struct device *mgr_dev = class_find_device(fpga_mgr_class, NULL, dev, 232 fpga_mgr_dev_match); 233 if (!mgr_dev) 234 return ERR_PTR(-ENODEV); 235 236 return __fpga_mgr_get(mgr_dev); 237 } 238 EXPORT_SYMBOL_GPL(fpga_mgr_get); 239 240 static int fpga_mgr_of_node_match(struct device *dev, const void *data) 241 { 242 return dev->of_node == data; 243 } 244 245 /** 246 * of_fpga_mgr_get - get an exclusive reference to a fpga mgr 247 * @node: device node 248 * 249 * Given a device node, get an exclusive reference to a fpga mgr. 250 * 251 * Return: fpga manager struct or IS_ERR() condition containing error code. 252 */ 253 struct fpga_manager *of_fpga_mgr_get(struct device_node *node) 254 { 255 struct device *dev; 256 257 dev = class_find_device(fpga_mgr_class, NULL, node, 258 fpga_mgr_of_node_match); 259 if (!dev) 260 return ERR_PTR(-ENODEV); 261 262 return __fpga_mgr_get(dev); 263 } 264 EXPORT_SYMBOL_GPL(of_fpga_mgr_get); 265 266 /** 267 * fpga_mgr_put - release a reference to a fpga manager 268 * @mgr: fpga manager structure 269 */ 270 void fpga_mgr_put(struct fpga_manager *mgr) 271 { 272 module_put(mgr->dev.parent->driver->owner); 273 mutex_unlock(&mgr->ref_mutex); 274 put_device(&mgr->dev); 275 } 276 EXPORT_SYMBOL_GPL(fpga_mgr_put); 277 278 /** 279 * fpga_mgr_register - register a low level fpga manager driver 280 * @dev: fpga manager device from pdev 281 * @name: fpga manager name 282 * @mops: pointer to structure of fpga manager ops 283 * @priv: fpga manager private data 284 * 285 * Return: 0 on success, negative error code otherwise. 286 */ 287 int fpga_mgr_register(struct device *dev, const char *name, 288 const struct fpga_manager_ops *mops, 289 void *priv) 290 { 291 struct fpga_manager *mgr; 292 int id, ret; 293 294 if (!mops || !mops->write_init || !mops->write || 295 !mops->write_complete || !mops->state) { 296 dev_err(dev, "Attempt to register without fpga_manager_ops\n"); 297 return -EINVAL; 298 } 299 300 if (!name || !strlen(name)) { 301 dev_err(dev, "Attempt to register with no name!\n"); 302 return -EINVAL; 303 } 304 305 mgr = kzalloc(sizeof(*mgr), GFP_KERNEL); 306 if (!mgr) 307 return -ENOMEM; 308 309 id = ida_simple_get(&fpga_mgr_ida, 0, 0, GFP_KERNEL); 310 if (id < 0) { 311 ret = id; 312 goto error_kfree; 313 } 314 315 mutex_init(&mgr->ref_mutex); 316 317 mgr->name = name; 318 mgr->mops = mops; 319 mgr->priv = priv; 320 321 /* 322 * Initialize framework state by requesting low level driver read state 323 * from device. FPGA may be in reset mode or may have been programmed 324 * by bootloader or EEPROM. 325 */ 326 mgr->state = mgr->mops->state(mgr); 327 328 device_initialize(&mgr->dev); 329 mgr->dev.class = fpga_mgr_class; 330 mgr->dev.parent = dev; 331 mgr->dev.of_node = dev->of_node; 332 mgr->dev.id = id; 333 dev_set_drvdata(dev, mgr); 334 335 ret = dev_set_name(&mgr->dev, "fpga%d", id); 336 if (ret) 337 goto error_device; 338 339 ret = device_add(&mgr->dev); 340 if (ret) 341 goto error_device; 342 343 dev_info(&mgr->dev, "%s registered\n", mgr->name); 344 345 return 0; 346 347 error_device: 348 ida_simple_remove(&fpga_mgr_ida, id); 349 error_kfree: 350 kfree(mgr); 351 352 return ret; 353 } 354 EXPORT_SYMBOL_GPL(fpga_mgr_register); 355 356 /** 357 * fpga_mgr_unregister - unregister a low level fpga manager driver 358 * @dev: fpga manager device from pdev 359 */ 360 void fpga_mgr_unregister(struct device *dev) 361 { 362 struct fpga_manager *mgr = dev_get_drvdata(dev); 363 364 dev_info(&mgr->dev, "%s %s\n", __func__, mgr->name); 365 366 /* 367 * If the low level driver provides a method for putting fpga into 368 * a desired state upon unregister, do it. 369 */ 370 if (mgr->mops->fpga_remove) 371 mgr->mops->fpga_remove(mgr); 372 373 device_unregister(&mgr->dev); 374 } 375 EXPORT_SYMBOL_GPL(fpga_mgr_unregister); 376 377 static void fpga_mgr_dev_release(struct device *dev) 378 { 379 struct fpga_manager *mgr = to_fpga_manager(dev); 380 381 ida_simple_remove(&fpga_mgr_ida, mgr->dev.id); 382 kfree(mgr); 383 } 384 385 static int __init fpga_mgr_class_init(void) 386 { 387 pr_info("FPGA manager framework\n"); 388 389 fpga_mgr_class = class_create(THIS_MODULE, "fpga_manager"); 390 if (IS_ERR(fpga_mgr_class)) 391 return PTR_ERR(fpga_mgr_class); 392 393 fpga_mgr_class->dev_groups = fpga_mgr_groups; 394 fpga_mgr_class->dev_release = fpga_mgr_dev_release; 395 396 return 0; 397 } 398 399 static void __exit fpga_mgr_class_exit(void) 400 { 401 class_destroy(fpga_mgr_class); 402 ida_destroy(&fpga_mgr_ida); 403 } 404 405 MODULE_AUTHOR("Alan Tull <atull@opensource.altera.com>"); 406 MODULE_DESCRIPTION("FPGA manager framework"); 407 MODULE_LICENSE("GPL v2"); 408 409 subsys_initcall(fpga_mgr_class_init); 410 module_exit(fpga_mgr_class_exit); 411