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  *     Xilinx products are not intended for use in life support appliances,
25  *     devices, or systems. Use in such applications is expressly prohibited.
26  *
27  *     (c) Copyright 2002 Xilinx Inc., Systems Engineering Group
28  *     (c) Copyright 2004 Xilinx Inc., Systems Engineering Group
29  *     (c) Copyright 2007-2008 Xilinx Inc.
30  *     All rights reserved.
31  *
32  *     You should have received a copy of the GNU General Public License along
33  *     with this program; if not, write to the Free Software Foundation, Inc.,
34  *     675 Mass Ave, Cambridge, MA 02139, USA.
35  *
36  *****************************************************************************/
37 
38 /*
39  * This is the code behind /dev/icap* -- it allows a user-space
40  * application to use the Xilinx ICAP subsystem.
41  *
42  * The following operations are possible:
43  *
44  * open         open the port and initialize for access.
45  * release      release port
46  * write        Write a bitstream to the configuration processor.
47  * read         Read a data stream from the configuration processor.
48  *
49  * After being opened, the port is initialized and accessed to avoid a
50  * corrupted first read which may occur with some hardware.  The port
51  * is left in a desynched state, requiring that a synch sequence be
52  * transmitted before any valid configuration data.  A user will have
53  * exclusive access to the device while it remains open, and the state
54  * of the ICAP cannot be guaranteed after the device is closed.  Note
55  * that a complete reset of the core and the state of the ICAP cannot
56  * be performed on many versions of the cores, hence users of this
57  * device should avoid making inconsistent accesses to the device.  In
58  * particular, accessing the read interface, without first generating
59  * a write containing a readback packet can leave the ICAP in an
60  * inaccessible state.
61  *
62  * Note that in order to use the read interface, it is first necessary
63  * to write a request packet to the write interface.  i.e., it is not
64  * possible to simply readback the bitstream (or any configuration
65  * bits) from a device without specifically requesting them first.
66  * The code to craft such packets is intended to be part of the
67  * user-space application code that uses this device.  The simplest
68  * way to use this interface is simply:
69  *
70  * cp foo.bit /dev/icap0
71  *
72  * Note that unless foo.bit is an appropriately constructed partial
73  * bitstream, this has a high likelyhood of overwriting the design
74  * currently programmed in the FPGA.
75  */
76 
77 #include <linux/version.h>
78 #include <linux/module.h>
79 #include <linux/kernel.h>
80 #include <linux/types.h>
81 #include <linux/ioport.h>
82 #include <linux/interrupt.h>
83 #include <linux/fcntl.h>
84 #include <linux/init.h>
85 #include <linux/poll.h>
86 #include <linux/proc_fs.h>
87 #include <linux/mutex.h>
88 #include <linux/sysctl.h>
89 #include <linux/version.h>
90 #include <linux/fs.h>
91 #include <linux/cdev.h>
92 #include <linux/platform_device.h>
93 
94 #include <asm/io.h>
95 #include <asm/uaccess.h>
96 #include <asm/system.h>
97 
98 #ifdef CONFIG_OF
99 /* For open firmware. */
100 #include <linux/of_device.h>
101 #include <linux/of_platform.h>
102 #endif
103 
104 #include "xilinx_hwicap.h"
105 #include "buffer_icap.h"
106 #include "fifo_icap.h"
107 
108 #define DRIVER_NAME "icap"
109 
110 #define HWICAP_REGS   (0x10000)
111 
112 #define XHWICAP_MAJOR 259
113 #define XHWICAP_MINOR 0
114 #define HWICAP_DEVICES 1
115 
116 /* An array, which is set to true when the device is registered. */
117 static bool probed_devices[HWICAP_DEVICES];
118 static struct mutex icap_sem;
119 
120 static struct class *icap_class;
121 
122 #define UNIMPLEMENTED 0xFFFF
123 
124 static const struct config_registers v2_config_registers = {
125 	.CRC = 0,
126 	.FAR = 1,
127 	.FDRI = 2,
128 	.FDRO = 3,
129 	.CMD = 4,
130 	.CTL = 5,
131 	.MASK = 6,
132 	.STAT = 7,
133 	.LOUT = 8,
134 	.COR = 9,
135 	.MFWR = 10,
136 	.FLR = 11,
137 	.KEY = 12,
138 	.CBC = 13,
139 	.IDCODE = 14,
140 	.AXSS = UNIMPLEMENTED,
141 	.C0R_1 = UNIMPLEMENTED,
142 	.CSOB = UNIMPLEMENTED,
143 	.WBSTAR = UNIMPLEMENTED,
144 	.TIMER = UNIMPLEMENTED,
145 	.BOOTSTS = UNIMPLEMENTED,
146 	.CTL_1 = UNIMPLEMENTED,
147 };
148 
149 static const struct config_registers v4_config_registers = {
150 	.CRC = 0,
151 	.FAR = 1,
152 	.FDRI = 2,
153 	.FDRO = 3,
154 	.CMD = 4,
155 	.CTL = 5,
156 	.MASK = 6,
157 	.STAT = 7,
158 	.LOUT = 8,
159 	.COR = 9,
160 	.MFWR = 10,
161 	.FLR = UNIMPLEMENTED,
162 	.KEY = UNIMPLEMENTED,
163 	.CBC = 11,
164 	.IDCODE = 12,
165 	.AXSS = 13,
166 	.C0R_1 = UNIMPLEMENTED,
167 	.CSOB = UNIMPLEMENTED,
168 	.WBSTAR = UNIMPLEMENTED,
169 	.TIMER = UNIMPLEMENTED,
170 	.BOOTSTS = UNIMPLEMENTED,
171 	.CTL_1 = UNIMPLEMENTED,
172 };
173 static const struct config_registers v5_config_registers = {
174 	.CRC = 0,
175 	.FAR = 1,
176 	.FDRI = 2,
177 	.FDRO = 3,
178 	.CMD = 4,
179 	.CTL = 5,
180 	.MASK = 6,
181 	.STAT = 7,
182 	.LOUT = 8,
183 	.COR = 9,
184 	.MFWR = 10,
185 	.FLR = UNIMPLEMENTED,
186 	.KEY = UNIMPLEMENTED,
187 	.CBC = 11,
188 	.IDCODE = 12,
189 	.AXSS = 13,
190 	.C0R_1 = 14,
191 	.CSOB = 15,
192 	.WBSTAR = 16,
193 	.TIMER = 17,
194 	.BOOTSTS = 18,
195 	.CTL_1 = 19,
196 };
197 
198 /**
199  * hwicap_command_desync - Send a DESYNC command to the ICAP port.
200  * @drvdata: a pointer to the drvdata.
201  *
202  * This command desynchronizes the ICAP After this command, a
203  * bitstream containing a NULL packet, followed by a SYNCH packet is
204  * required before the ICAP will recognize commands.
205  */
206 static int hwicap_command_desync(struct hwicap_drvdata *drvdata)
207 {
208 	u32 buffer[4];
209 	u32 index = 0;
210 
211 	/*
212 	 * Create the data to be written to the ICAP.
213 	 */
214 	buffer[index++] = hwicap_type_1_write(drvdata->config_regs->CMD) | 1;
215 	buffer[index++] = XHI_CMD_DESYNCH;
216 	buffer[index++] = XHI_NOOP_PACKET;
217 	buffer[index++] = XHI_NOOP_PACKET;
218 
219 	/*
220 	 * Write the data to the FIFO and intiate the transfer of data present
221 	 * in the FIFO to the ICAP device.
222 	 */
223 	return drvdata->config->set_configuration(drvdata,
224 			&buffer[0], index);
225 }
226 
227 /**
228  * hwicap_get_configuration_register - Query a configuration register.
229  * @drvdata: a pointer to the drvdata.
230  * @reg: a constant which represents the configuration
231  *		register value to be returned.
232  * 		Examples:  XHI_IDCODE, XHI_FLR.
233  * @reg_data: returns the value of the register.
234  *
235  * Sends a query packet to the ICAP and then receives the response.
236  * The icap is left in Synched state.
237  */
238 static int hwicap_get_configuration_register(struct hwicap_drvdata *drvdata,
239 		u32 reg, u32 *reg_data)
240 {
241 	int status;
242 	u32 buffer[6];
243 	u32 index = 0;
244 
245 	/*
246 	 * Create the data to be written to the ICAP.
247 	 */
248 	buffer[index++] = XHI_DUMMY_PACKET;
249 	buffer[index++] = XHI_NOOP_PACKET;
250 	buffer[index++] = XHI_SYNC_PACKET;
251 	buffer[index++] = XHI_NOOP_PACKET;
252 	buffer[index++] = XHI_NOOP_PACKET;
253 
254 	/*
255 	 * Write the data to the FIFO and initiate the transfer of data present
256 	 * in the FIFO to the ICAP device.
257 	 */
258 	status = drvdata->config->set_configuration(drvdata,
259 						    &buffer[0], index);
260 	if (status)
261 		return status;
262 
263 	/* If the syncword was not found, then we need to start over. */
264 	status = drvdata->config->get_status(drvdata);
265 	if ((status & XHI_SR_DALIGN_MASK) != XHI_SR_DALIGN_MASK)
266 		return -EIO;
267 
268 	index = 0;
269 	buffer[index++] = hwicap_type_1_read(reg) | 1;
270 	buffer[index++] = XHI_NOOP_PACKET;
271 	buffer[index++] = XHI_NOOP_PACKET;
272 
273 	/*
274 	 * Write the data to the FIFO and intiate the transfer of data present
275 	 * in the FIFO to the ICAP device.
276 	 */
277 	status = drvdata->config->set_configuration(drvdata,
278 			&buffer[0], index);
279 	if (status)
280 		return status;
281 
282 	/*
283 	 * Read the configuration register
284 	 */
285 	status = drvdata->config->get_configuration(drvdata, reg_data, 1);
286 	if (status)
287 		return status;
288 
289 	return 0;
290 }
291 
292 static int hwicap_initialize_hwicap(struct hwicap_drvdata *drvdata)
293 {
294 	int status;
295 	u32 idcode;
296 
297 	dev_dbg(drvdata->dev, "initializing\n");
298 
299 	/* Abort any current transaction, to make sure we have the
300 	 * ICAP in a good state. */
301 	dev_dbg(drvdata->dev, "Reset...\n");
302 	drvdata->config->reset(drvdata);
303 
304 	dev_dbg(drvdata->dev, "Desync...\n");
305 	status = hwicap_command_desync(drvdata);
306 	if (status)
307 		return status;
308 
309 	/* Attempt to read the IDCODE from ICAP.  This
310 	 * may not be returned correctly, due to the design of the
311 	 * hardware.
312 	 */
313 	dev_dbg(drvdata->dev, "Reading IDCODE...\n");
314 	status = hwicap_get_configuration_register(
315 			drvdata, drvdata->config_regs->IDCODE, &idcode);
316 	dev_dbg(drvdata->dev, "IDCODE = %x\n", idcode);
317 	if (status)
318 		return status;
319 
320 	dev_dbg(drvdata->dev, "Desync...\n");
321 	status = hwicap_command_desync(drvdata);
322 	if (status)
323 		return status;
324 
325 	return 0;
326 }
327 
328 static ssize_t
329 hwicap_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
330 {
331 	struct hwicap_drvdata *drvdata = file->private_data;
332 	ssize_t bytes_to_read = 0;
333 	u32 *kbuf;
334 	u32 words;
335 	u32 bytes_remaining;
336 	int status;
337 
338 	status = mutex_lock_interruptible(&drvdata->sem);
339 	if (status)
340 		return status;
341 
342 	if (drvdata->read_buffer_in_use) {
343 		/* If there are leftover bytes in the buffer, just */
344 		/* return them and don't try to read more from the */
345 		/* ICAP device. */
346 		bytes_to_read =
347 			(count < drvdata->read_buffer_in_use) ? count :
348 			drvdata->read_buffer_in_use;
349 
350 		/* Return the data currently in the read buffer. */
351 		if (copy_to_user(buf, drvdata->read_buffer, bytes_to_read)) {
352 			status = -EFAULT;
353 			goto error;
354 		}
355 		drvdata->read_buffer_in_use -= bytes_to_read;
356 		memmove(drvdata->read_buffer,
357 		       drvdata->read_buffer + bytes_to_read,
358 		       4 - bytes_to_read);
359 	} else {
360 		/* Get new data from the ICAP, and return was was requested. */
361 		kbuf = (u32 *) get_zeroed_page(GFP_KERNEL);
362 		if (!kbuf) {
363 			status = -ENOMEM;
364 			goto error;
365 		}
366 
367 		/* The ICAP device is only able to read complete */
368 		/* words.  If a number of bytes that do not correspond */
369 		/* to complete words is requested, then we read enough */
370 		/* words to get the required number of bytes, and then */
371 		/* save the remaining bytes for the next read. */
372 
373 		/* Determine the number of words to read, rounding up */
374 		/* if necessary. */
375 		words = ((count + 3) >> 2);
376 		bytes_to_read = words << 2;
377 
378 		if (bytes_to_read > PAGE_SIZE)
379 			bytes_to_read = PAGE_SIZE;
380 
381 		/* Ensure we only read a complete number of words. */
382 		bytes_remaining = bytes_to_read & 3;
383 		bytes_to_read &= ~3;
384 		words = bytes_to_read >> 2;
385 
386 		status = drvdata->config->get_configuration(drvdata,
387 				kbuf, words);
388 
389 		/* If we didn't read correctly, then bail out. */
390 		if (status) {
391 			free_page((unsigned long)kbuf);
392 			goto error;
393 		}
394 
395 		/* If we fail to return the data to the user, then bail out. */
396 		if (copy_to_user(buf, kbuf, bytes_to_read)) {
397 			free_page((unsigned long)kbuf);
398 			status = -EFAULT;
399 			goto error;
400 		}
401 		memcpy(drvdata->read_buffer,
402 		       kbuf,
403 		       bytes_remaining);
404 		drvdata->read_buffer_in_use = bytes_remaining;
405 		free_page((unsigned long)kbuf);
406 	}
407 	status = bytes_to_read;
408  error:
409 	mutex_unlock(&drvdata->sem);
410 	return status;
411 }
412 
413 static ssize_t
414 hwicap_write(struct file *file, const char __user *buf,
415 		size_t count, loff_t *ppos)
416 {
417 	struct hwicap_drvdata *drvdata = file->private_data;
418 	ssize_t written = 0;
419 	ssize_t left = count;
420 	u32 *kbuf;
421 	ssize_t len;
422 	ssize_t status;
423 
424 	status = mutex_lock_interruptible(&drvdata->sem);
425 	if (status)
426 		return status;
427 
428 	left += drvdata->write_buffer_in_use;
429 
430 	/* Only write multiples of 4 bytes. */
431 	if (left < 4) {
432 		status = 0;
433 		goto error;
434 	}
435 
436 	kbuf = (u32 *) __get_free_page(GFP_KERNEL);
437 	if (!kbuf) {
438 		status = -ENOMEM;
439 		goto error;
440 	}
441 
442 	while (left > 3) {
443 		/* only write multiples of 4 bytes, so there might */
444 		/* be as many as 3 bytes left (at the end). */
445 		len = left;
446 
447 		if (len > PAGE_SIZE)
448 			len = PAGE_SIZE;
449 		len &= ~3;
450 
451 		if (drvdata->write_buffer_in_use) {
452 			memcpy(kbuf, drvdata->write_buffer,
453 					drvdata->write_buffer_in_use);
454 			if (copy_from_user(
455 			    (((char *)kbuf) + drvdata->write_buffer_in_use),
456 			    buf + written,
457 			    len - (drvdata->write_buffer_in_use))) {
458 				free_page((unsigned long)kbuf);
459 				status = -EFAULT;
460 				goto error;
461 			}
462 		} else {
463 			if (copy_from_user(kbuf, buf + written, len)) {
464 				free_page((unsigned long)kbuf);
465 				status = -EFAULT;
466 				goto error;
467 			}
468 		}
469 
470 		status = drvdata->config->set_configuration(drvdata,
471 				kbuf, len >> 2);
472 
473 		if (status) {
474 			free_page((unsigned long)kbuf);
475 			status = -EFAULT;
476 			goto error;
477 		}
478 		if (drvdata->write_buffer_in_use) {
479 			len -= drvdata->write_buffer_in_use;
480 			left -= drvdata->write_buffer_in_use;
481 			drvdata->write_buffer_in_use = 0;
482 		}
483 		written += len;
484 		left -= len;
485 	}
486 	if ((left > 0) && (left < 4)) {
487 		if (!copy_from_user(drvdata->write_buffer,
488 						buf + written, left)) {
489 			drvdata->write_buffer_in_use = left;
490 			written += left;
491 			left = 0;
492 		}
493 	}
494 
495 	free_page((unsigned long)kbuf);
496 	status = written;
497  error:
498 	mutex_unlock(&drvdata->sem);
499 	return status;
500 }
501 
502 static int hwicap_open(struct inode *inode, struct file *file)
503 {
504 	struct hwicap_drvdata *drvdata;
505 	int status;
506 
507 	drvdata = container_of(inode->i_cdev, struct hwicap_drvdata, cdev);
508 
509 	status = mutex_lock_interruptible(&drvdata->sem);
510 	if (status)
511 		return status;
512 
513 	if (drvdata->is_open) {
514 		status = -EBUSY;
515 		goto error;
516 	}
517 
518 	status = hwicap_initialize_hwicap(drvdata);
519 	if (status) {
520 		dev_err(drvdata->dev, "Failed to open file");
521 		goto error;
522 	}
523 
524 	file->private_data = drvdata;
525 	drvdata->write_buffer_in_use = 0;
526 	drvdata->read_buffer_in_use = 0;
527 	drvdata->is_open = 1;
528 
529  error:
530 	mutex_unlock(&drvdata->sem);
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 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 };
570 
571 static int __devinit hwicap_setup(struct device *dev, int id,
572 		const struct resource *regs_res,
573 		const struct hwicap_driver_config *config,
574 		const struct config_registers *config_regs)
575 {
576 	dev_t devt;
577 	struct hwicap_drvdata *drvdata = NULL;
578 	int retval = 0;
579 
580 	dev_info(dev, "Xilinx icap port driver\n");
581 
582 	mutex_lock(&icap_sem);
583 
584 	if (id < 0) {
585 		for (id = 0; id < HWICAP_DEVICES; id++)
586 			if (!probed_devices[id])
587 				break;
588 	}
589 	if (id < 0 || id >= HWICAP_DEVICES) {
590 		mutex_unlock(&icap_sem);
591 		dev_err(dev, "%s%i too large\n", DRIVER_NAME, id);
592 		return -EINVAL;
593 	}
594 	if (probed_devices[id]) {
595 		mutex_unlock(&icap_sem);
596 		dev_err(dev, "cannot assign to %s%i; it is already in use\n",
597 			DRIVER_NAME, id);
598 		return -EBUSY;
599 	}
600 
601 	probed_devices[id] = 1;
602 	mutex_unlock(&icap_sem);
603 
604 	devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR + id);
605 
606 	drvdata = kzalloc(sizeof(struct hwicap_drvdata), GFP_KERNEL);
607 	if (!drvdata) {
608 		dev_err(dev, "Couldn't allocate device private record\n");
609 		retval = -ENOMEM;
610 		goto failed0;
611 	}
612 	dev_set_drvdata(dev, (void *)drvdata);
613 
614 	if (!regs_res) {
615 		dev_err(dev, "Couldn't get registers resource\n");
616 		retval = -EFAULT;
617 		goto failed1;
618 	}
619 
620 	drvdata->mem_start = regs_res->start;
621 	drvdata->mem_end = regs_res->end;
622 	drvdata->mem_size = regs_res->end - regs_res->start + 1;
623 
624 	if (!request_mem_region(drvdata->mem_start,
625 					drvdata->mem_size, DRIVER_NAME)) {
626 		dev_err(dev, "Couldn't lock memory region at %Lx\n",
627 			regs_res->start);
628 		retval = -EBUSY;
629 		goto failed1;
630 	}
631 
632 	drvdata->devt = devt;
633 	drvdata->dev = dev;
634 	drvdata->base_address = ioremap(drvdata->mem_start, drvdata->mem_size);
635 	if (!drvdata->base_address) {
636 		dev_err(dev, "ioremap() failed\n");
637 		goto failed2;
638 	}
639 
640 	drvdata->config = config;
641 	drvdata->config_regs = config_regs;
642 
643 	mutex_init(&drvdata->sem);
644 	drvdata->is_open = 0;
645 
646 	dev_info(dev, "ioremap %lx to %p with size %Lx\n",
647 		 (unsigned long int)drvdata->mem_start,
648 			drvdata->base_address, drvdata->mem_size);
649 
650 	cdev_init(&drvdata->cdev, &hwicap_fops);
651 	drvdata->cdev.owner = THIS_MODULE;
652 	retval = cdev_add(&drvdata->cdev, devt, 1);
653 	if (retval) {
654 		dev_err(dev, "cdev_add() failed\n");
655 		goto failed3;
656 	}
657 	/*  devfs_mk_cdev(devt, S_IFCHR|S_IRUGO|S_IWUGO, DRIVER_NAME); */
658 	device_create(icap_class, dev, devt, "%s%d", DRIVER_NAME, id);
659 	return 0;		/* success */
660 
661  failed3:
662 	iounmap(drvdata->base_address);
663 
664  failed2:
665 	release_mem_region(regs_res->start, drvdata->mem_size);
666 
667  failed1:
668 	kfree(drvdata);
669 
670  failed0:
671 	mutex_lock(&icap_sem);
672 	probed_devices[id] = 0;
673 	mutex_unlock(&icap_sem);
674 
675 	return retval;
676 }
677 
678 static struct hwicap_driver_config buffer_icap_config = {
679 	.get_configuration = buffer_icap_get_configuration,
680 	.set_configuration = buffer_icap_set_configuration,
681 	.get_status = buffer_icap_get_status,
682 	.reset = buffer_icap_reset,
683 };
684 
685 static struct hwicap_driver_config fifo_icap_config = {
686 	.get_configuration = fifo_icap_get_configuration,
687 	.set_configuration = fifo_icap_set_configuration,
688 	.get_status = fifo_icap_get_status,
689 	.reset = fifo_icap_reset,
690 };
691 
692 static int __devexit hwicap_remove(struct device *dev)
693 {
694 	struct hwicap_drvdata *drvdata;
695 
696 	drvdata = (struct hwicap_drvdata *)dev_get_drvdata(dev);
697 
698 	if (!drvdata)
699 		return 0;
700 
701 	device_destroy(icap_class, drvdata->devt);
702 	cdev_del(&drvdata->cdev);
703 	iounmap(drvdata->base_address);
704 	release_mem_region(drvdata->mem_start, drvdata->mem_size);
705 	kfree(drvdata);
706 	dev_set_drvdata(dev, NULL);
707 
708 	mutex_lock(&icap_sem);
709 	probed_devices[MINOR(dev->devt)-XHWICAP_MINOR] = 0;
710 	mutex_unlock(&icap_sem);
711 	return 0;		/* success */
712 }
713 
714 static int __devinit hwicap_drv_probe(struct platform_device *pdev)
715 {
716 	struct resource *res;
717 	const struct config_registers *regs;
718 	const char *family;
719 
720 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
721 	if (!res)
722 		return -ENODEV;
723 
724 	/* It's most likely that we're using V4, if the family is not
725 	   specified */
726 	regs = &v4_config_registers;
727 	family = pdev->dev.platform_data;
728 
729 	if (family) {
730 		if (!strcmp(family, "virtex2p")) {
731 			regs = &v2_config_registers;
732 		} else if (!strcmp(family, "virtex4")) {
733 			regs = &v4_config_registers;
734 		} else if (!strcmp(family, "virtex5")) {
735 			regs = &v5_config_registers;
736 		}
737 	}
738 
739 	return hwicap_setup(&pdev->dev, pdev->id, res,
740 			&buffer_icap_config, regs);
741 }
742 
743 static int __devexit hwicap_drv_remove(struct platform_device *pdev)
744 {
745 	return hwicap_remove(&pdev->dev);
746 }
747 
748 static struct platform_driver hwicap_platform_driver = {
749 	.probe = hwicap_drv_probe,
750 	.remove = hwicap_drv_remove,
751 	.driver = {
752 		.owner = THIS_MODULE,
753 		.name = DRIVER_NAME,
754 	},
755 };
756 
757 /* ---------------------------------------------------------------------
758  * OF bus binding
759  */
760 
761 #if defined(CONFIG_OF)
762 static int __devinit
763 hwicap_of_probe(struct of_device *op, const struct of_device_id *match)
764 {
765 	struct resource res;
766 	const unsigned int *id;
767 	const char *family;
768 	int rc;
769 	const struct hwicap_driver_config *config = match->data;
770 	const struct config_registers *regs;
771 
772 	dev_dbg(&op->dev, "hwicap_of_probe(%p, %p)\n", op, match);
773 
774 	rc = of_address_to_resource(op->node, 0, &res);
775 	if (rc) {
776 		dev_err(&op->dev, "invalid address\n");
777 		return rc;
778 	}
779 
780 	id = of_get_property(op->node, "port-number", NULL);
781 
782 	/* It's most likely that we're using V4, if the family is not
783 	   specified */
784 	regs = &v4_config_registers;
785 	family = of_get_property(op->node, "xlnx,family", NULL);
786 
787 	if (family) {
788 		if (!strcmp(family, "virtex2p")) {
789 			regs = &v2_config_registers;
790 		} else if (!strcmp(family, "virtex4")) {
791 			regs = &v4_config_registers;
792 		} else if (!strcmp(family, "virtex5")) {
793 			regs = &v5_config_registers;
794 		}
795 	}
796 	return hwicap_setup(&op->dev, id ? *id : -1, &res, config,
797 			regs);
798 }
799 
800 static int __devexit hwicap_of_remove(struct of_device *op)
801 {
802 	return hwicap_remove(&op->dev);
803 }
804 
805 /* Match table for of_platform binding */
806 static const struct of_device_id __devinitconst hwicap_of_match[] = {
807 	{ .compatible = "xlnx,opb-hwicap-1.00.b", .data = &buffer_icap_config},
808 	{ .compatible = "xlnx,xps-hwicap-1.00.a", .data = &fifo_icap_config},
809 	{},
810 };
811 MODULE_DEVICE_TABLE(of, hwicap_of_match);
812 
813 static struct of_platform_driver hwicap_of_driver = {
814 	.owner = THIS_MODULE,
815 	.name = DRIVER_NAME,
816 	.match_table = hwicap_of_match,
817 	.probe = hwicap_of_probe,
818 	.remove = __devexit_p(hwicap_of_remove),
819 	.driver = {
820 		.name = DRIVER_NAME,
821 	},
822 };
823 
824 /* Registration helpers to keep the number of #ifdefs to a minimum */
825 static inline int __init hwicap_of_register(void)
826 {
827 	pr_debug("hwicap: calling of_register_platform_driver()\n");
828 	return of_register_platform_driver(&hwicap_of_driver);
829 }
830 
831 static inline void __exit hwicap_of_unregister(void)
832 {
833 	of_unregister_platform_driver(&hwicap_of_driver);
834 }
835 #else /* CONFIG_OF */
836 /* CONFIG_OF not enabled; do nothing helpers */
837 static inline int __init hwicap_of_register(void) { return 0; }
838 static inline void __exit hwicap_of_unregister(void) { }
839 #endif /* CONFIG_OF */
840 
841 static int __init hwicap_module_init(void)
842 {
843 	dev_t devt;
844 	int retval;
845 
846 	icap_class = class_create(THIS_MODULE, "xilinx_config");
847 	mutex_init(&icap_sem);
848 
849 	devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR);
850 	retval = register_chrdev_region(devt,
851 					HWICAP_DEVICES,
852 					DRIVER_NAME);
853 	if (retval < 0)
854 		return retval;
855 
856 	retval = platform_driver_register(&hwicap_platform_driver);
857 
858 	if (retval)
859 		goto failed1;
860 
861 	retval = hwicap_of_register();
862 
863 	if (retval)
864 		goto failed2;
865 
866 	return retval;
867 
868  failed2:
869 	platform_driver_unregister(&hwicap_platform_driver);
870 
871  failed1:
872 	unregister_chrdev_region(devt, HWICAP_DEVICES);
873 
874 	return retval;
875 }
876 
877 static void __exit hwicap_module_cleanup(void)
878 {
879 	dev_t devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR);
880 
881 	class_destroy(icap_class);
882 
883 	platform_driver_unregister(&hwicap_platform_driver);
884 
885 	hwicap_of_unregister();
886 
887 	unregister_chrdev_region(devt, HWICAP_DEVICES);
888 }
889 
890 module_init(hwicap_module_init);
891 module_exit(hwicap_module_cleanup);
892 
893 MODULE_AUTHOR("Xilinx, Inc; Xilinx Research Labs Group");
894 MODULE_DESCRIPTION("Xilinx ICAP Port Driver");
895 MODULE_LICENSE("GPL");
896