1 /*****************************************************************************
2  *
3  *     Author: Xilinx, Inc.
4  *
5  *     This program is free software; you can redistribute it and/or modify it
6  *     under the terms of the GNU General Public License as published by the
7  *     Free Software Foundation; either version 2 of the License, or (at your
8  *     option) any later version.
9  *
10  *     XILINX IS PROVIDING THIS DESIGN, CODE, OR INFORMATION "AS IS"
11  *     AS A COURTESY TO YOU, SOLELY FOR USE IN DEVELOPING PROGRAMS AND
12  *     SOLUTIONS FOR XILINX DEVICES.  BY PROVIDING THIS DESIGN, CODE,
13  *     OR INFORMATION AS ONE POSSIBLE IMPLEMENTATION OF THIS FEATURE,
14  *     APPLICATION OR STANDARD, XILINX IS MAKING NO REPRESENTATION
15  *     THAT THIS IMPLEMENTATION IS FREE FROM ANY CLAIMS OF INFRINGEMENT,
16  *     AND YOU ARE RESPONSIBLE FOR OBTAINING ANY RIGHTS YOU MAY REQUIRE
17  *     FOR YOUR IMPLEMENTATION.  XILINX EXPRESSLY DISCLAIMS ANY
18  *     WARRANTY WHATSOEVER WITH RESPECT TO THE ADEQUACY OF THE
19  *     IMPLEMENTATION, INCLUDING BUT NOT LIMITED TO ANY WARRANTIES OR
20  *     REPRESENTATIONS THAT THIS IMPLEMENTATION IS FREE FROM CLAIMS OF
21  *     INFRINGEMENT, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
22  *     FOR A PARTICULAR PURPOSE.
23  *
24  *     (c) Copyright 2002 Xilinx Inc., Systems Engineering Group
25  *     (c) Copyright 2004 Xilinx Inc., Systems Engineering Group
26  *     (c) Copyright 2007-2008 Xilinx Inc.
27  *     All rights reserved.
28  *
29  *     You should have received a copy of the GNU General Public License along
30  *     with this program; if not, write to the Free Software Foundation, Inc.,
31  *     675 Mass Ave, Cambridge, MA 02139, USA.
32  *
33  *****************************************************************************/
34 
35 /*
36  * This is the code behind /dev/icap* -- it allows a user-space
37  * application to use the Xilinx ICAP subsystem.
38  *
39  * The following operations are possible:
40  *
41  * open         open the port and initialize for access.
42  * release      release port
43  * write        Write a bitstream to the configuration processor.
44  * read         Read a data stream from the configuration processor.
45  *
46  * After being opened, the port is initialized and accessed to avoid a
47  * corrupted first read which may occur with some hardware.  The port
48  * is left in a desynched state, requiring that a synch sequence be
49  * transmitted before any valid configuration data.  A user will have
50  * exclusive access to the device while it remains open, and the state
51  * of the ICAP cannot be guaranteed after the device is closed.  Note
52  * that a complete reset of the core and the state of the ICAP cannot
53  * be performed on many versions of the cores, hence users of this
54  * device should avoid making inconsistent accesses to the device.  In
55  * particular, accessing the read interface, without first generating
56  * a write containing a readback packet can leave the ICAP in an
57  * inaccessible state.
58  *
59  * Note that in order to use the read interface, it is first necessary
60  * to write a request packet to the write interface.  i.e., it is not
61  * possible to simply readback the bitstream (or any configuration
62  * bits) from a device without specifically requesting them first.
63  * The code to craft such packets is intended to be part of the
64  * user-space application code that uses this device.  The simplest
65  * way to use this interface is simply:
66  *
67  * cp foo.bit /dev/icap0
68  *
69  * Note that unless foo.bit is an appropriately constructed partial
70  * bitstream, this has a high likelihood of overwriting the design
71  * currently programmed in the FPGA.
72  */
73 
74 #include <linux/module.h>
75 #include <linux/kernel.h>
76 #include <linux/types.h>
77 #include <linux/ioport.h>
78 #include <linux/interrupt.h>
79 #include <linux/fcntl.h>
80 #include <linux/init.h>
81 #include <linux/poll.h>
82 #include <linux/proc_fs.h>
83 #include <linux/mutex.h>
84 #include <linux/sysctl.h>
85 #include <linux/fs.h>
86 #include <linux/cdev.h>
87 #include <linux/platform_device.h>
88 #include <linux/slab.h>
89 
90 #include <asm/io.h>
91 #include <asm/uaccess.h>
92 
93 #ifdef CONFIG_OF
94 /* For open firmware. */
95 #include <linux/of_address.h>
96 #include <linux/of_device.h>
97 #include <linux/of_platform.h>
98 #endif
99 
100 #include "xilinx_hwicap.h"
101 #include "buffer_icap.h"
102 #include "fifo_icap.h"
103 
104 #define DRIVER_NAME "icap"
105 
106 #define HWICAP_REGS   (0x10000)
107 
108 #define XHWICAP_MAJOR 259
109 #define XHWICAP_MINOR 0
110 #define HWICAP_DEVICES 1
111 
112 /* An array, which is set to true when the device is registered. */
113 static DEFINE_MUTEX(hwicap_mutex);
114 static bool probed_devices[HWICAP_DEVICES];
115 static struct mutex icap_sem;
116 
117 static struct class *icap_class;
118 
119 #define UNIMPLEMENTED 0xFFFF
120 
121 static const struct config_registers v2_config_registers = {
122 	.CRC = 0,
123 	.FAR = 1,
124 	.FDRI = 2,
125 	.FDRO = 3,
126 	.CMD = 4,
127 	.CTL = 5,
128 	.MASK = 6,
129 	.STAT = 7,
130 	.LOUT = 8,
131 	.COR = 9,
132 	.MFWR = 10,
133 	.FLR = 11,
134 	.KEY = 12,
135 	.CBC = 13,
136 	.IDCODE = 14,
137 	.AXSS = UNIMPLEMENTED,
138 	.C0R_1 = UNIMPLEMENTED,
139 	.CSOB = UNIMPLEMENTED,
140 	.WBSTAR = UNIMPLEMENTED,
141 	.TIMER = UNIMPLEMENTED,
142 	.BOOTSTS = UNIMPLEMENTED,
143 	.CTL_1 = UNIMPLEMENTED,
144 };
145 
146 static const struct config_registers v4_config_registers = {
147 	.CRC = 0,
148 	.FAR = 1,
149 	.FDRI = 2,
150 	.FDRO = 3,
151 	.CMD = 4,
152 	.CTL = 5,
153 	.MASK = 6,
154 	.STAT = 7,
155 	.LOUT = 8,
156 	.COR = 9,
157 	.MFWR = 10,
158 	.FLR = UNIMPLEMENTED,
159 	.KEY = UNIMPLEMENTED,
160 	.CBC = 11,
161 	.IDCODE = 12,
162 	.AXSS = 13,
163 	.C0R_1 = UNIMPLEMENTED,
164 	.CSOB = UNIMPLEMENTED,
165 	.WBSTAR = UNIMPLEMENTED,
166 	.TIMER = UNIMPLEMENTED,
167 	.BOOTSTS = UNIMPLEMENTED,
168 	.CTL_1 = UNIMPLEMENTED,
169 };
170 static const struct config_registers v5_config_registers = {
171 	.CRC = 0,
172 	.FAR = 1,
173 	.FDRI = 2,
174 	.FDRO = 3,
175 	.CMD = 4,
176 	.CTL = 5,
177 	.MASK = 6,
178 	.STAT = 7,
179 	.LOUT = 8,
180 	.COR = 9,
181 	.MFWR = 10,
182 	.FLR = UNIMPLEMENTED,
183 	.KEY = UNIMPLEMENTED,
184 	.CBC = 11,
185 	.IDCODE = 12,
186 	.AXSS = 13,
187 	.C0R_1 = 14,
188 	.CSOB = 15,
189 	.WBSTAR = 16,
190 	.TIMER = 17,
191 	.BOOTSTS = 18,
192 	.CTL_1 = 19,
193 };
194 
195 /**
196  * hwicap_command_desync - Send a DESYNC command to the ICAP port.
197  * @drvdata: a pointer to the drvdata.
198  *
199  * This command desynchronizes the ICAP After this command, a
200  * bitstream containing a NULL packet, followed by a SYNCH packet is
201  * required before the ICAP will recognize commands.
202  */
203 static int hwicap_command_desync(struct hwicap_drvdata *drvdata)
204 {
205 	u32 buffer[4];
206 	u32 index = 0;
207 
208 	/*
209 	 * Create the data to be written to the ICAP.
210 	 */
211 	buffer[index++] = hwicap_type_1_write(drvdata->config_regs->CMD) | 1;
212 	buffer[index++] = XHI_CMD_DESYNCH;
213 	buffer[index++] = XHI_NOOP_PACKET;
214 	buffer[index++] = XHI_NOOP_PACKET;
215 
216 	/*
217 	 * Write the data to the FIFO and intiate the transfer of data present
218 	 * in the FIFO to the ICAP device.
219 	 */
220 	return drvdata->config->set_configuration(drvdata,
221 			&buffer[0], index);
222 }
223 
224 /**
225  * hwicap_get_configuration_register - Query a configuration register.
226  * @drvdata: a pointer to the drvdata.
227  * @reg: a constant which represents the configuration
228  *		register value to be returned.
229  * 		Examples:  XHI_IDCODE, XHI_FLR.
230  * @reg_data: returns the value of the register.
231  *
232  * Sends a query packet to the ICAP and then receives the response.
233  * The icap is left in Synched state.
234  */
235 static int hwicap_get_configuration_register(struct hwicap_drvdata *drvdata,
236 		u32 reg, u32 *reg_data)
237 {
238 	int status;
239 	u32 buffer[6];
240 	u32 index = 0;
241 
242 	/*
243 	 * Create the data to be written to the ICAP.
244 	 */
245 	buffer[index++] = XHI_DUMMY_PACKET;
246 	buffer[index++] = XHI_NOOP_PACKET;
247 	buffer[index++] = XHI_SYNC_PACKET;
248 	buffer[index++] = XHI_NOOP_PACKET;
249 	buffer[index++] = XHI_NOOP_PACKET;
250 
251 	/*
252 	 * Write the data to the FIFO and initiate the transfer of data present
253 	 * in the FIFO to the ICAP device.
254 	 */
255 	status = drvdata->config->set_configuration(drvdata,
256 						    &buffer[0], index);
257 	if (status)
258 		return status;
259 
260 	/* If the syncword was not found, then we need to start over. */
261 	status = drvdata->config->get_status(drvdata);
262 	if ((status & XHI_SR_DALIGN_MASK) != XHI_SR_DALIGN_MASK)
263 		return -EIO;
264 
265 	index = 0;
266 	buffer[index++] = hwicap_type_1_read(reg) | 1;
267 	buffer[index++] = XHI_NOOP_PACKET;
268 	buffer[index++] = XHI_NOOP_PACKET;
269 
270 	/*
271 	 * Write the data to the FIFO and intiate the transfer of data present
272 	 * in the FIFO to the ICAP device.
273 	 */
274 	status = drvdata->config->set_configuration(drvdata,
275 			&buffer[0], index);
276 	if (status)
277 		return status;
278 
279 	/*
280 	 * Read the configuration register
281 	 */
282 	status = drvdata->config->get_configuration(drvdata, reg_data, 1);
283 	if (status)
284 		return status;
285 
286 	return 0;
287 }
288 
289 static int hwicap_initialize_hwicap(struct hwicap_drvdata *drvdata)
290 {
291 	int status;
292 	u32 idcode;
293 
294 	dev_dbg(drvdata->dev, "initializing\n");
295 
296 	/* Abort any current transaction, to make sure we have the
297 	 * ICAP in a good state. */
298 	dev_dbg(drvdata->dev, "Reset...\n");
299 	drvdata->config->reset(drvdata);
300 
301 	dev_dbg(drvdata->dev, "Desync...\n");
302 	status = hwicap_command_desync(drvdata);
303 	if (status)
304 		return status;
305 
306 	/* Attempt to read the IDCODE from ICAP.  This
307 	 * may not be returned correctly, due to the design of the
308 	 * hardware.
309 	 */
310 	dev_dbg(drvdata->dev, "Reading IDCODE...\n");
311 	status = hwicap_get_configuration_register(
312 			drvdata, drvdata->config_regs->IDCODE, &idcode);
313 	dev_dbg(drvdata->dev, "IDCODE = %x\n", idcode);
314 	if (status)
315 		return status;
316 
317 	dev_dbg(drvdata->dev, "Desync...\n");
318 	status = hwicap_command_desync(drvdata);
319 	if (status)
320 		return status;
321 
322 	return 0;
323 }
324 
325 static ssize_t
326 hwicap_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
327 {
328 	struct hwicap_drvdata *drvdata = file->private_data;
329 	ssize_t bytes_to_read = 0;
330 	u32 *kbuf;
331 	u32 words;
332 	u32 bytes_remaining;
333 	int status;
334 
335 	status = mutex_lock_interruptible(&drvdata->sem);
336 	if (status)
337 		return status;
338 
339 	if (drvdata->read_buffer_in_use) {
340 		/* If there are leftover bytes in the buffer, just */
341 		/* return them and don't try to read more from the */
342 		/* ICAP device. */
343 		bytes_to_read =
344 			(count < drvdata->read_buffer_in_use) ? count :
345 			drvdata->read_buffer_in_use;
346 
347 		/* Return the data currently in the read buffer. */
348 		if (copy_to_user(buf, drvdata->read_buffer, bytes_to_read)) {
349 			status = -EFAULT;
350 			goto error;
351 		}
352 		drvdata->read_buffer_in_use -= bytes_to_read;
353 		memmove(drvdata->read_buffer,
354 		       drvdata->read_buffer + bytes_to_read,
355 		       4 - bytes_to_read);
356 	} else {
357 		/* Get new data from the ICAP, and return was was requested. */
358 		kbuf = (u32 *) get_zeroed_page(GFP_KERNEL);
359 		if (!kbuf) {
360 			status = -ENOMEM;
361 			goto error;
362 		}
363 
364 		/* The ICAP device is only able to read complete */
365 		/* words.  If a number of bytes that do not correspond */
366 		/* to complete words is requested, then we read enough */
367 		/* words to get the required number of bytes, and then */
368 		/* save the remaining bytes for the next read. */
369 
370 		/* Determine the number of words to read, rounding up */
371 		/* if necessary. */
372 		words = ((count + 3) >> 2);
373 		bytes_to_read = words << 2;
374 
375 		if (bytes_to_read > PAGE_SIZE)
376 			bytes_to_read = PAGE_SIZE;
377 
378 		/* Ensure we only read a complete number of words. */
379 		bytes_remaining = bytes_to_read & 3;
380 		bytes_to_read &= ~3;
381 		words = bytes_to_read >> 2;
382 
383 		status = drvdata->config->get_configuration(drvdata,
384 				kbuf, words);
385 
386 		/* If we didn't read correctly, then bail out. */
387 		if (status) {
388 			free_page((unsigned long)kbuf);
389 			goto error;
390 		}
391 
392 		/* If we fail to return the data to the user, then bail out. */
393 		if (copy_to_user(buf, kbuf, bytes_to_read)) {
394 			free_page((unsigned long)kbuf);
395 			status = -EFAULT;
396 			goto error;
397 		}
398 		memcpy(drvdata->read_buffer,
399 		       kbuf,
400 		       bytes_remaining);
401 		drvdata->read_buffer_in_use = bytes_remaining;
402 		free_page((unsigned long)kbuf);
403 	}
404 	status = bytes_to_read;
405  error:
406 	mutex_unlock(&drvdata->sem);
407 	return status;
408 }
409 
410 static ssize_t
411 hwicap_write(struct file *file, const char __user *buf,
412 		size_t count, loff_t *ppos)
413 {
414 	struct hwicap_drvdata *drvdata = file->private_data;
415 	ssize_t written = 0;
416 	ssize_t left = count;
417 	u32 *kbuf;
418 	ssize_t len;
419 	ssize_t status;
420 
421 	status = mutex_lock_interruptible(&drvdata->sem);
422 	if (status)
423 		return status;
424 
425 	left += drvdata->write_buffer_in_use;
426 
427 	/* Only write multiples of 4 bytes. */
428 	if (left < 4) {
429 		status = 0;
430 		goto error;
431 	}
432 
433 	kbuf = (u32 *) __get_free_page(GFP_KERNEL);
434 	if (!kbuf) {
435 		status = -ENOMEM;
436 		goto error;
437 	}
438 
439 	while (left > 3) {
440 		/* only write multiples of 4 bytes, so there might */
441 		/* be as many as 3 bytes left (at the end). */
442 		len = left;
443 
444 		if (len > PAGE_SIZE)
445 			len = PAGE_SIZE;
446 		len &= ~3;
447 
448 		if (drvdata->write_buffer_in_use) {
449 			memcpy(kbuf, drvdata->write_buffer,
450 					drvdata->write_buffer_in_use);
451 			if (copy_from_user(
452 			    (((char *)kbuf) + drvdata->write_buffer_in_use),
453 			    buf + written,
454 			    len - (drvdata->write_buffer_in_use))) {
455 				free_page((unsigned long)kbuf);
456 				status = -EFAULT;
457 				goto error;
458 			}
459 		} else {
460 			if (copy_from_user(kbuf, buf + written, len)) {
461 				free_page((unsigned long)kbuf);
462 				status = -EFAULT;
463 				goto error;
464 			}
465 		}
466 
467 		status = drvdata->config->set_configuration(drvdata,
468 				kbuf, len >> 2);
469 
470 		if (status) {
471 			free_page((unsigned long)kbuf);
472 			status = -EFAULT;
473 			goto error;
474 		}
475 		if (drvdata->write_buffer_in_use) {
476 			len -= drvdata->write_buffer_in_use;
477 			left -= drvdata->write_buffer_in_use;
478 			drvdata->write_buffer_in_use = 0;
479 		}
480 		written += len;
481 		left -= len;
482 	}
483 	if ((left > 0) && (left < 4)) {
484 		if (!copy_from_user(drvdata->write_buffer,
485 						buf + written, left)) {
486 			drvdata->write_buffer_in_use = left;
487 			written += left;
488 			left = 0;
489 		}
490 	}
491 
492 	free_page((unsigned long)kbuf);
493 	status = written;
494  error:
495 	mutex_unlock(&drvdata->sem);
496 	return status;
497 }
498 
499 static int hwicap_open(struct inode *inode, struct file *file)
500 {
501 	struct hwicap_drvdata *drvdata;
502 	int status;
503 
504 	mutex_lock(&hwicap_mutex);
505 	drvdata = container_of(inode->i_cdev, struct hwicap_drvdata, cdev);
506 
507 	status = mutex_lock_interruptible(&drvdata->sem);
508 	if (status)
509 		goto out;
510 
511 	if (drvdata->is_open) {
512 		status = -EBUSY;
513 		goto error;
514 	}
515 
516 	status = hwicap_initialize_hwicap(drvdata);
517 	if (status) {
518 		dev_err(drvdata->dev, "Failed to open file");
519 		goto error;
520 	}
521 
522 	file->private_data = drvdata;
523 	drvdata->write_buffer_in_use = 0;
524 	drvdata->read_buffer_in_use = 0;
525 	drvdata->is_open = 1;
526 
527  error:
528 	mutex_unlock(&drvdata->sem);
529  out:
530 	mutex_unlock(&hwicap_mutex);
531 	return status;
532 }
533 
534 static int hwicap_release(struct inode *inode, struct file *file)
535 {
536 	struct hwicap_drvdata *drvdata = file->private_data;
537 	int i;
538 	int status = 0;
539 
540 	mutex_lock(&drvdata->sem);
541 
542 	if (drvdata->write_buffer_in_use) {
543 		/* Flush write buffer. */
544 		for (i = drvdata->write_buffer_in_use; i < 4; i++)
545 			drvdata->write_buffer[i] = 0;
546 
547 		status = drvdata->config->set_configuration(drvdata,
548 				(u32 *) drvdata->write_buffer, 1);
549 		if (status)
550 			goto error;
551 	}
552 
553 	status = hwicap_command_desync(drvdata);
554 	if (status)
555 		goto error;
556 
557  error:
558 	drvdata->is_open = 0;
559 	mutex_unlock(&drvdata->sem);
560 	return status;
561 }
562 
563 static const struct file_operations hwicap_fops = {
564 	.owner = THIS_MODULE,
565 	.write = hwicap_write,
566 	.read = hwicap_read,
567 	.open = hwicap_open,
568 	.release = hwicap_release,
569 	.llseek = noop_llseek,
570 };
571 
572 static int __devinit hwicap_setup(struct device *dev, int id,
573 		const struct resource *regs_res,
574 		const struct hwicap_driver_config *config,
575 		const struct config_registers *config_regs)
576 {
577 	dev_t devt;
578 	struct hwicap_drvdata *drvdata = NULL;
579 	int retval = 0;
580 
581 	dev_info(dev, "Xilinx icap port driver\n");
582 
583 	mutex_lock(&icap_sem);
584 
585 	if (id < 0) {
586 		for (id = 0; id < HWICAP_DEVICES; id++)
587 			if (!probed_devices[id])
588 				break;
589 	}
590 	if (id < 0 || id >= HWICAP_DEVICES) {
591 		mutex_unlock(&icap_sem);
592 		dev_err(dev, "%s%i too large\n", DRIVER_NAME, id);
593 		return -EINVAL;
594 	}
595 	if (probed_devices[id]) {
596 		mutex_unlock(&icap_sem);
597 		dev_err(dev, "cannot assign to %s%i; it is already in use\n",
598 			DRIVER_NAME, id);
599 		return -EBUSY;
600 	}
601 
602 	probed_devices[id] = 1;
603 	mutex_unlock(&icap_sem);
604 
605 	devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR + id);
606 
607 	drvdata = kzalloc(sizeof(struct hwicap_drvdata), GFP_KERNEL);
608 	if (!drvdata) {
609 		dev_err(dev, "Couldn't allocate device private record\n");
610 		retval = -ENOMEM;
611 		goto failed0;
612 	}
613 	dev_set_drvdata(dev, (void *)drvdata);
614 
615 	if (!regs_res) {
616 		dev_err(dev, "Couldn't get registers resource\n");
617 		retval = -EFAULT;
618 		goto failed1;
619 	}
620 
621 	drvdata->mem_start = regs_res->start;
622 	drvdata->mem_end = regs_res->end;
623 	drvdata->mem_size = resource_size(regs_res);
624 
625 	if (!request_mem_region(drvdata->mem_start,
626 					drvdata->mem_size, DRIVER_NAME)) {
627 		dev_err(dev, "Couldn't lock memory region at %Lx\n",
628 			(unsigned long long) regs_res->start);
629 		retval = -EBUSY;
630 		goto failed1;
631 	}
632 
633 	drvdata->devt = devt;
634 	drvdata->dev = dev;
635 	drvdata->base_address = ioremap(drvdata->mem_start, drvdata->mem_size);
636 	if (!drvdata->base_address) {
637 		dev_err(dev, "ioremap() failed\n");
638 		goto failed2;
639 	}
640 
641 	drvdata->config = config;
642 	drvdata->config_regs = config_regs;
643 
644 	mutex_init(&drvdata->sem);
645 	drvdata->is_open = 0;
646 
647 	dev_info(dev, "ioremap %llx to %p with size %llx\n",
648 		 (unsigned long long) drvdata->mem_start,
649 		 drvdata->base_address,
650 		 (unsigned long long) drvdata->mem_size);
651 
652 	cdev_init(&drvdata->cdev, &hwicap_fops);
653 	drvdata->cdev.owner = THIS_MODULE;
654 	retval = cdev_add(&drvdata->cdev, devt, 1);
655 	if (retval) {
656 		dev_err(dev, "cdev_add() failed\n");
657 		goto failed3;
658 	}
659 
660 	device_create(icap_class, dev, devt, NULL, "%s%d", DRIVER_NAME, id);
661 	return 0;		/* success */
662 
663  failed3:
664 	iounmap(drvdata->base_address);
665 
666  failed2:
667 	release_mem_region(regs_res->start, drvdata->mem_size);
668 
669  failed1:
670 	kfree(drvdata);
671 
672  failed0:
673 	mutex_lock(&icap_sem);
674 	probed_devices[id] = 0;
675 	mutex_unlock(&icap_sem);
676 
677 	return retval;
678 }
679 
680 static struct hwicap_driver_config buffer_icap_config = {
681 	.get_configuration = buffer_icap_get_configuration,
682 	.set_configuration = buffer_icap_set_configuration,
683 	.get_status = buffer_icap_get_status,
684 	.reset = buffer_icap_reset,
685 };
686 
687 static struct hwicap_driver_config fifo_icap_config = {
688 	.get_configuration = fifo_icap_get_configuration,
689 	.set_configuration = fifo_icap_set_configuration,
690 	.get_status = fifo_icap_get_status,
691 	.reset = fifo_icap_reset,
692 };
693 
694 static int __devexit hwicap_remove(struct device *dev)
695 {
696 	struct hwicap_drvdata *drvdata;
697 
698 	drvdata = (struct hwicap_drvdata *)dev_get_drvdata(dev);
699 
700 	if (!drvdata)
701 		return 0;
702 
703 	device_destroy(icap_class, drvdata->devt);
704 	cdev_del(&drvdata->cdev);
705 	iounmap(drvdata->base_address);
706 	release_mem_region(drvdata->mem_start, drvdata->mem_size);
707 	kfree(drvdata);
708 	dev_set_drvdata(dev, NULL);
709 
710 	mutex_lock(&icap_sem);
711 	probed_devices[MINOR(dev->devt)-XHWICAP_MINOR] = 0;
712 	mutex_unlock(&icap_sem);
713 	return 0;		/* success */
714 }
715 
716 #ifdef CONFIG_OF
717 static int __devinit hwicap_of_probe(struct platform_device *op,
718 				     const struct hwicap_driver_config *config)
719 {
720 	struct resource res;
721 	const unsigned int *id;
722 	const char *family;
723 	int rc;
724 	const struct config_registers *regs;
725 
726 
727 	rc = of_address_to_resource(op->dev.of_node, 0, &res);
728 	if (rc) {
729 		dev_err(&op->dev, "invalid address\n");
730 		return rc;
731 	}
732 
733 	id = of_get_property(op->dev.of_node, "port-number", NULL);
734 
735 	/* It's most likely that we're using V4, if the family is not
736 	   specified */
737 	regs = &v4_config_registers;
738 	family = of_get_property(op->dev.of_node, "xlnx,family", NULL);
739 
740 	if (family) {
741 		if (!strcmp(family, "virtex2p")) {
742 			regs = &v2_config_registers;
743 		} else if (!strcmp(family, "virtex4")) {
744 			regs = &v4_config_registers;
745 		} else if (!strcmp(family, "virtex5")) {
746 			regs = &v5_config_registers;
747 		}
748 	}
749 	return hwicap_setup(&op->dev, id ? *id : -1, &res, config,
750 			regs);
751 }
752 #else
753 static inline int hwicap_of_probe(struct platform_device *op,
754 				  const struct hwicap_driver_config *config)
755 {
756 	return -EINVAL;
757 }
758 #endif /* CONFIG_OF */
759 
760 static const struct of_device_id __devinitconst hwicap_of_match[];
761 static int __devinit hwicap_drv_probe(struct platform_device *pdev)
762 {
763 	const struct of_device_id *match;
764 	struct resource *res;
765 	const struct config_registers *regs;
766 	const char *family;
767 
768 	match = of_match_device(hwicap_of_match, &pdev->dev);
769 	if (match)
770 		return hwicap_of_probe(pdev, match->data);
771 
772 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
773 	if (!res)
774 		return -ENODEV;
775 
776 	/* It's most likely that we're using V4, if the family is not
777 	   specified */
778 	regs = &v4_config_registers;
779 	family = pdev->dev.platform_data;
780 
781 	if (family) {
782 		if (!strcmp(family, "virtex2p")) {
783 			regs = &v2_config_registers;
784 		} else if (!strcmp(family, "virtex4")) {
785 			regs = &v4_config_registers;
786 		} else if (!strcmp(family, "virtex5")) {
787 			regs = &v5_config_registers;
788 		}
789 	}
790 
791 	return hwicap_setup(&pdev->dev, pdev->id, res,
792 			&buffer_icap_config, regs);
793 }
794 
795 static int __devexit hwicap_drv_remove(struct platform_device *pdev)
796 {
797 	return hwicap_remove(&pdev->dev);
798 }
799 
800 #ifdef CONFIG_OF
801 /* Match table for device tree binding */
802 static const struct of_device_id __devinitconst hwicap_of_match[] = {
803 	{ .compatible = "xlnx,opb-hwicap-1.00.b", .data = &buffer_icap_config},
804 	{ .compatible = "xlnx,xps-hwicap-1.00.a", .data = &fifo_icap_config},
805 	{},
806 };
807 MODULE_DEVICE_TABLE(of, hwicap_of_match);
808 #else
809 #define hwicap_of_match NULL
810 #endif
811 
812 static struct platform_driver hwicap_platform_driver = {
813 	.probe = hwicap_drv_probe,
814 	.remove = hwicap_drv_remove,
815 	.driver = {
816 		.owner = THIS_MODULE,
817 		.name = DRIVER_NAME,
818 		.of_match_table = hwicap_of_match,
819 	},
820 };
821 
822 static int __init hwicap_module_init(void)
823 {
824 	dev_t devt;
825 	int retval;
826 
827 	icap_class = class_create(THIS_MODULE, "xilinx_config");
828 	mutex_init(&icap_sem);
829 
830 	devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR);
831 	retval = register_chrdev_region(devt,
832 					HWICAP_DEVICES,
833 					DRIVER_NAME);
834 	if (retval < 0)
835 		return retval;
836 
837 	retval = platform_driver_register(&hwicap_platform_driver);
838 	if (retval)
839 		goto failed;
840 
841 	return retval;
842 
843  failed:
844 	unregister_chrdev_region(devt, HWICAP_DEVICES);
845 
846 	return retval;
847 }
848 
849 static void __exit hwicap_module_cleanup(void)
850 {
851 	dev_t devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR);
852 
853 	class_destroy(icap_class);
854 
855 	platform_driver_unregister(&hwicap_platform_driver);
856 
857 	unregister_chrdev_region(devt, HWICAP_DEVICES);
858 }
859 
860 module_init(hwicap_module_init);
861 module_exit(hwicap_module_cleanup);
862 
863 MODULE_AUTHOR("Xilinx, Inc; Xilinx Research Labs Group");
864 MODULE_DESCRIPTION("Xilinx ICAP Port Driver");
865 MODULE_LICENSE("GPL");
866