x86/mm/pat: Don't report PAT on CPUs that don't support it
[linux/fpc-iii.git] / drivers / fpga / fpga-mgr.c
blob86d2cb203533ff41df1d33d1cc4f312696e6ebf6
1 /*
2 * FPGA Manager Core
4 * Copyright (C) 2013-2015 Altera Corporation
6 * With code from the mailing list:
7 * Copyright (C) 2013 Xilinx, Inc.
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.
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.
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/>.
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 #include <linux/scatterlist.h>
29 #include <linux/highmem.h>
31 static DEFINE_IDA(fpga_mgr_ida);
32 static struct class *fpga_mgr_class;
35 * Call the low level driver's write_init function. This will do the
36 * device-specific things to get the FPGA into the state where it is ready to
37 * receive an FPGA image. The low level driver only gets to see the first
38 * initial_header_size bytes in the buffer.
40 static int fpga_mgr_write_init_buf(struct fpga_manager *mgr,
41 struct fpga_image_info *info,
42 const char *buf, size_t count)
44 int ret;
46 mgr->state = FPGA_MGR_STATE_WRITE_INIT;
47 if (!mgr->mops->initial_header_size)
48 ret = mgr->mops->write_init(mgr, info, NULL, 0);
49 else
50 ret = mgr->mops->write_init(
51 mgr, info, buf, min(mgr->mops->initial_header_size, count));
53 if (ret) {
54 dev_err(&mgr->dev, "Error preparing FPGA for writing\n");
55 mgr->state = FPGA_MGR_STATE_WRITE_INIT_ERR;
56 return ret;
59 return 0;
62 static int fpga_mgr_write_init_sg(struct fpga_manager *mgr,
63 struct fpga_image_info *info,
64 struct sg_table *sgt)
66 struct sg_mapping_iter miter;
67 size_t len;
68 char *buf;
69 int ret;
71 if (!mgr->mops->initial_header_size)
72 return fpga_mgr_write_init_buf(mgr, info, NULL, 0);
75 * First try to use miter to map the first fragment to access the
76 * header, this is the typical path.
78 sg_miter_start(&miter, sgt->sgl, sgt->nents, SG_MITER_FROM_SG);
79 if (sg_miter_next(&miter) &&
80 miter.length >= mgr->mops->initial_header_size) {
81 ret = fpga_mgr_write_init_buf(mgr, info, miter.addr,
82 miter.length);
83 sg_miter_stop(&miter);
84 return ret;
86 sg_miter_stop(&miter);
88 /* Otherwise copy the fragments into temporary memory. */
89 buf = kmalloc(mgr->mops->initial_header_size, GFP_KERNEL);
90 if (!buf)
91 return -ENOMEM;
93 len = sg_copy_to_buffer(sgt->sgl, sgt->nents, buf,
94 mgr->mops->initial_header_size);
95 ret = fpga_mgr_write_init_buf(mgr, info, buf, len);
97 kfree(buf);
99 return ret;
103 * After all the FPGA image has been written, do the device specific steps to
104 * finish and set the FPGA into operating mode.
106 static int fpga_mgr_write_complete(struct fpga_manager *mgr,
107 struct fpga_image_info *info)
109 int ret;
111 mgr->state = FPGA_MGR_STATE_WRITE_COMPLETE;
112 ret = mgr->mops->write_complete(mgr, info);
113 if (ret) {
114 dev_err(&mgr->dev, "Error after writing image data to FPGA\n");
115 mgr->state = FPGA_MGR_STATE_WRITE_COMPLETE_ERR;
116 return ret;
118 mgr->state = FPGA_MGR_STATE_OPERATING;
120 return 0;
124 * fpga_mgr_buf_load_sg - load fpga from image in buffer from a scatter list
125 * @mgr: fpga manager
126 * @info: fpga image specific information
127 * @sgt: scatterlist table
129 * Step the low level fpga manager through the device-specific steps of getting
130 * an FPGA ready to be configured, writing the image to it, then doing whatever
131 * post-configuration steps necessary. This code assumes the caller got the
132 * mgr pointer from of_fpga_mgr_get() or fpga_mgr_get() and checked that it is
133 * not an error code.
135 * This is the preferred entry point for FPGA programming, it does not require
136 * any contiguous kernel memory.
138 * Return: 0 on success, negative error code otherwise.
140 int fpga_mgr_buf_load_sg(struct fpga_manager *mgr, struct fpga_image_info *info,
141 struct sg_table *sgt)
143 int ret;
145 ret = fpga_mgr_write_init_sg(mgr, info, sgt);
146 if (ret)
147 return ret;
149 /* Write the FPGA image to the FPGA. */
150 mgr->state = FPGA_MGR_STATE_WRITE;
151 if (mgr->mops->write_sg) {
152 ret = mgr->mops->write_sg(mgr, sgt);
153 } else {
154 struct sg_mapping_iter miter;
156 sg_miter_start(&miter, sgt->sgl, sgt->nents, SG_MITER_FROM_SG);
157 while (sg_miter_next(&miter)) {
158 ret = mgr->mops->write(mgr, miter.addr, miter.length);
159 if (ret)
160 break;
162 sg_miter_stop(&miter);
165 if (ret) {
166 dev_err(&mgr->dev, "Error while writing image data to FPGA\n");
167 mgr->state = FPGA_MGR_STATE_WRITE_ERR;
168 return ret;
171 return fpga_mgr_write_complete(mgr, info);
173 EXPORT_SYMBOL_GPL(fpga_mgr_buf_load_sg);
175 static int fpga_mgr_buf_load_mapped(struct fpga_manager *mgr,
176 struct fpga_image_info *info,
177 const char *buf, size_t count)
179 int ret;
181 ret = fpga_mgr_write_init_buf(mgr, info, buf, count);
182 if (ret)
183 return ret;
186 * Write the FPGA image to the FPGA.
188 mgr->state = FPGA_MGR_STATE_WRITE;
189 ret = mgr->mops->write(mgr, buf, count);
190 if (ret) {
191 dev_err(&mgr->dev, "Error while writing image data to FPGA\n");
192 mgr->state = FPGA_MGR_STATE_WRITE_ERR;
193 return ret;
196 return fpga_mgr_write_complete(mgr, info);
200 * fpga_mgr_buf_load - load fpga from image in buffer
201 * @mgr: fpga manager
202 * @flags: flags setting fpga confuration modes
203 * @buf: buffer contain fpga image
204 * @count: byte count of buf
206 * Step the low level fpga manager through the device-specific steps of getting
207 * an FPGA ready to be configured, writing the image to it, then doing whatever
208 * post-configuration steps necessary. This code assumes the caller got the
209 * mgr pointer from of_fpga_mgr_get() and checked that it is not an error code.
211 * Return: 0 on success, negative error code otherwise.
213 int fpga_mgr_buf_load(struct fpga_manager *mgr, struct fpga_image_info *info,
214 const char *buf, size_t count)
216 struct page **pages;
217 struct sg_table sgt;
218 const void *p;
219 int nr_pages;
220 int index;
221 int rc;
224 * This is just a fast path if the caller has already created a
225 * contiguous kernel buffer and the driver doesn't require SG, non-SG
226 * drivers will still work on the slow path.
228 if (mgr->mops->write)
229 return fpga_mgr_buf_load_mapped(mgr, info, buf, count);
232 * Convert the linear kernel pointer into a sg_table of pages for use
233 * by the driver.
235 nr_pages = DIV_ROUND_UP((unsigned long)buf + count, PAGE_SIZE) -
236 (unsigned long)buf / PAGE_SIZE;
237 pages = kmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL);
238 if (!pages)
239 return -ENOMEM;
241 p = buf - offset_in_page(buf);
242 for (index = 0; index < nr_pages; index++) {
243 if (is_vmalloc_addr(p))
244 pages[index] = vmalloc_to_page(p);
245 else
246 pages[index] = kmap_to_page((void *)p);
247 if (!pages[index]) {
248 kfree(pages);
249 return -EFAULT;
251 p += PAGE_SIZE;
255 * The temporary pages list is used to code share the merging algorithm
256 * in sg_alloc_table_from_pages
258 rc = sg_alloc_table_from_pages(&sgt, pages, index, offset_in_page(buf),
259 count, GFP_KERNEL);
260 kfree(pages);
261 if (rc)
262 return rc;
264 rc = fpga_mgr_buf_load_sg(mgr, info, &sgt);
265 sg_free_table(&sgt);
267 return rc;
269 EXPORT_SYMBOL_GPL(fpga_mgr_buf_load);
272 * fpga_mgr_firmware_load - request firmware and load to fpga
273 * @mgr: fpga manager
274 * @info: fpga image specific information
275 * @image_name: name of image file on the firmware search path
277 * Request an FPGA image using the firmware class, then write out to the FPGA.
278 * Update the state before each step to provide info on what step failed if
279 * there is a failure. This code assumes the caller got the mgr pointer
280 * from of_fpga_mgr_get() or fpga_mgr_get() and checked that it is not an error
281 * code.
283 * Return: 0 on success, negative error code otherwise.
285 int fpga_mgr_firmware_load(struct fpga_manager *mgr,
286 struct fpga_image_info *info,
287 const char *image_name)
289 struct device *dev = &mgr->dev;
290 const struct firmware *fw;
291 int ret;
293 dev_info(dev, "writing %s to %s\n", image_name, mgr->name);
295 mgr->state = FPGA_MGR_STATE_FIRMWARE_REQ;
297 ret = request_firmware(&fw, image_name, dev);
298 if (ret) {
299 mgr->state = FPGA_MGR_STATE_FIRMWARE_REQ_ERR;
300 dev_err(dev, "Error requesting firmware %s\n", image_name);
301 return ret;
304 ret = fpga_mgr_buf_load(mgr, info, fw->data, fw->size);
306 release_firmware(fw);
308 return ret;
310 EXPORT_SYMBOL_GPL(fpga_mgr_firmware_load);
312 static const char * const state_str[] = {
313 [FPGA_MGR_STATE_UNKNOWN] = "unknown",
314 [FPGA_MGR_STATE_POWER_OFF] = "power off",
315 [FPGA_MGR_STATE_POWER_UP] = "power up",
316 [FPGA_MGR_STATE_RESET] = "reset",
318 /* requesting FPGA image from firmware */
319 [FPGA_MGR_STATE_FIRMWARE_REQ] = "firmware request",
320 [FPGA_MGR_STATE_FIRMWARE_REQ_ERR] = "firmware request error",
322 /* Preparing FPGA to receive image */
323 [FPGA_MGR_STATE_WRITE_INIT] = "write init",
324 [FPGA_MGR_STATE_WRITE_INIT_ERR] = "write init error",
326 /* Writing image to FPGA */
327 [FPGA_MGR_STATE_WRITE] = "write",
328 [FPGA_MGR_STATE_WRITE_ERR] = "write error",
330 /* Finishing configuration after image has been written */
331 [FPGA_MGR_STATE_WRITE_COMPLETE] = "write complete",
332 [FPGA_MGR_STATE_WRITE_COMPLETE_ERR] = "write complete error",
334 /* FPGA reports to be in normal operating mode */
335 [FPGA_MGR_STATE_OPERATING] = "operating",
338 static ssize_t name_show(struct device *dev,
339 struct device_attribute *attr, char *buf)
341 struct fpga_manager *mgr = to_fpga_manager(dev);
343 return sprintf(buf, "%s\n", mgr->name);
346 static ssize_t state_show(struct device *dev,
347 struct device_attribute *attr, char *buf)
349 struct fpga_manager *mgr = to_fpga_manager(dev);
351 return sprintf(buf, "%s\n", state_str[mgr->state]);
354 static DEVICE_ATTR_RO(name);
355 static DEVICE_ATTR_RO(state);
357 static struct attribute *fpga_mgr_attrs[] = {
358 &dev_attr_name.attr,
359 &dev_attr_state.attr,
360 NULL,
362 ATTRIBUTE_GROUPS(fpga_mgr);
364 struct fpga_manager *__fpga_mgr_get(struct device *dev)
366 struct fpga_manager *mgr;
367 int ret = -ENODEV;
369 mgr = to_fpga_manager(dev);
370 if (!mgr)
371 goto err_dev;
373 /* Get exclusive use of fpga manager */
374 if (!mutex_trylock(&mgr->ref_mutex)) {
375 ret = -EBUSY;
376 goto err_dev;
379 if (!try_module_get(dev->parent->driver->owner))
380 goto err_ll_mod;
382 return mgr;
384 err_ll_mod:
385 mutex_unlock(&mgr->ref_mutex);
386 err_dev:
387 put_device(dev);
388 return ERR_PTR(ret);
391 static int fpga_mgr_dev_match(struct device *dev, const void *data)
393 return dev->parent == data;
397 * fpga_mgr_get - get an exclusive reference to a fpga mgr
398 * @dev: parent device that fpga mgr was registered with
400 * Given a device, get an exclusive reference to a fpga mgr.
402 * Return: fpga manager struct or IS_ERR() condition containing error code.
404 struct fpga_manager *fpga_mgr_get(struct device *dev)
406 struct device *mgr_dev = class_find_device(fpga_mgr_class, NULL, dev,
407 fpga_mgr_dev_match);
408 if (!mgr_dev)
409 return ERR_PTR(-ENODEV);
411 return __fpga_mgr_get(mgr_dev);
413 EXPORT_SYMBOL_GPL(fpga_mgr_get);
415 static int fpga_mgr_of_node_match(struct device *dev, const void *data)
417 return dev->of_node == data;
421 * of_fpga_mgr_get - get an exclusive reference to a fpga mgr
422 * @node: device node
424 * Given a device node, get an exclusive reference to a fpga mgr.
426 * Return: fpga manager struct or IS_ERR() condition containing error code.
428 struct fpga_manager *of_fpga_mgr_get(struct device_node *node)
430 struct device *dev;
432 dev = class_find_device(fpga_mgr_class, NULL, node,
433 fpga_mgr_of_node_match);
434 if (!dev)
435 return ERR_PTR(-ENODEV);
437 return __fpga_mgr_get(dev);
439 EXPORT_SYMBOL_GPL(of_fpga_mgr_get);
442 * fpga_mgr_put - release a reference to a fpga manager
443 * @mgr: fpga manager structure
445 void fpga_mgr_put(struct fpga_manager *mgr)
447 module_put(mgr->dev.parent->driver->owner);
448 mutex_unlock(&mgr->ref_mutex);
449 put_device(&mgr->dev);
451 EXPORT_SYMBOL_GPL(fpga_mgr_put);
454 * fpga_mgr_register - register a low level fpga manager driver
455 * @dev: fpga manager device from pdev
456 * @name: fpga manager name
457 * @mops: pointer to structure of fpga manager ops
458 * @priv: fpga manager private data
460 * Return: 0 on success, negative error code otherwise.
462 int fpga_mgr_register(struct device *dev, const char *name,
463 const struct fpga_manager_ops *mops,
464 void *priv)
466 struct fpga_manager *mgr;
467 int id, ret;
469 if (!mops || !mops->write_complete || !mops->state ||
470 !mops->write_init || (!mops->write && !mops->write_sg) ||
471 (mops->write && mops->write_sg)) {
472 dev_err(dev, "Attempt to register without fpga_manager_ops\n");
473 return -EINVAL;
476 if (!name || !strlen(name)) {
477 dev_err(dev, "Attempt to register with no name!\n");
478 return -EINVAL;
481 mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
482 if (!mgr)
483 return -ENOMEM;
485 id = ida_simple_get(&fpga_mgr_ida, 0, 0, GFP_KERNEL);
486 if (id < 0) {
487 ret = id;
488 goto error_kfree;
491 mutex_init(&mgr->ref_mutex);
493 mgr->name = name;
494 mgr->mops = mops;
495 mgr->priv = priv;
498 * Initialize framework state by requesting low level driver read state
499 * from device. FPGA may be in reset mode or may have been programmed
500 * by bootloader or EEPROM.
502 mgr->state = mgr->mops->state(mgr);
504 device_initialize(&mgr->dev);
505 mgr->dev.class = fpga_mgr_class;
506 mgr->dev.parent = dev;
507 mgr->dev.of_node = dev->of_node;
508 mgr->dev.id = id;
509 dev_set_drvdata(dev, mgr);
511 ret = dev_set_name(&mgr->dev, "fpga%d", id);
512 if (ret)
513 goto error_device;
515 ret = device_add(&mgr->dev);
516 if (ret)
517 goto error_device;
519 dev_info(&mgr->dev, "%s registered\n", mgr->name);
521 return 0;
523 error_device:
524 ida_simple_remove(&fpga_mgr_ida, id);
525 error_kfree:
526 kfree(mgr);
528 return ret;
530 EXPORT_SYMBOL_GPL(fpga_mgr_register);
533 * fpga_mgr_unregister - unregister a low level fpga manager driver
534 * @dev: fpga manager device from pdev
536 void fpga_mgr_unregister(struct device *dev)
538 struct fpga_manager *mgr = dev_get_drvdata(dev);
540 dev_info(&mgr->dev, "%s %s\n", __func__, mgr->name);
543 * If the low level driver provides a method for putting fpga into
544 * a desired state upon unregister, do it.
546 if (mgr->mops->fpga_remove)
547 mgr->mops->fpga_remove(mgr);
549 device_unregister(&mgr->dev);
551 EXPORT_SYMBOL_GPL(fpga_mgr_unregister);
553 static void fpga_mgr_dev_release(struct device *dev)
555 struct fpga_manager *mgr = to_fpga_manager(dev);
557 ida_simple_remove(&fpga_mgr_ida, mgr->dev.id);
558 kfree(mgr);
561 static int __init fpga_mgr_class_init(void)
563 pr_info("FPGA manager framework\n");
565 fpga_mgr_class = class_create(THIS_MODULE, "fpga_manager");
566 if (IS_ERR(fpga_mgr_class))
567 return PTR_ERR(fpga_mgr_class);
569 fpga_mgr_class->dev_groups = fpga_mgr_groups;
570 fpga_mgr_class->dev_release = fpga_mgr_dev_release;
572 return 0;
575 static void __exit fpga_mgr_class_exit(void)
577 class_destroy(fpga_mgr_class);
578 ida_destroy(&fpga_mgr_ida);
581 MODULE_AUTHOR("Alan Tull <atull@opensource.altera.com>");
582 MODULE_DESCRIPTION("FPGA manager framework");
583 MODULE_LICENSE("GPL v2");
585 subsys_initcall(fpga_mgr_class_init);
586 module_exit(fpga_mgr_class_exit);