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/smp_lock.h>
89 #include <linux/sysctl.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 	lock_kernel();
508 	drvdata = container_of(inode->i_cdev, struct hwicap_drvdata, cdev);
509 
510 	status = mutex_lock_interruptible(&drvdata->sem);
511 	if (status)
512 		goto out;
513 
514 	if (drvdata->is_open) {
515 		status = -EBUSY;
516 		goto error;
517 	}
518 
519 	status = hwicap_initialize_hwicap(drvdata);
520 	if (status) {
521 		dev_err(drvdata->dev, "Failed to open file");
522 		goto error;
523 	}
524 
525 	file->private_data = drvdata;
526 	drvdata->write_buffer_in_use = 0;
527 	drvdata->read_buffer_in_use = 0;
528 	drvdata->is_open = 1;
529 
530  error:
531 	mutex_unlock(&drvdata->sem);
532  out:
533 	unlock_kernel();
534 	return status;
535 }
536 
537 static int hwicap_release(struct inode *inode, struct file *file)
538 {
539 	struct hwicap_drvdata *drvdata = file->private_data;
540 	int i;
541 	int status = 0;
542 
543 	mutex_lock(&drvdata->sem);
544 
545 	if (drvdata->write_buffer_in_use) {
546 		/* Flush write buffer. */
547 		for (i = drvdata->write_buffer_in_use; i < 4; i++)
548 			drvdata->write_buffer[i] = 0;
549 
550 		status = drvdata->config->set_configuration(drvdata,
551 				(u32 *) drvdata->write_buffer, 1);
552 		if (status)
553 			goto error;
554 	}
555 
556 	status = hwicap_command_desync(drvdata);
557 	if (status)
558 		goto error;
559 
560  error:
561 	drvdata->is_open = 0;
562 	mutex_unlock(&drvdata->sem);
563 	return status;
564 }
565 
566 static struct file_operations hwicap_fops = {
567 	.owner = THIS_MODULE,
568 	.write = hwicap_write,
569 	.read = hwicap_read,
570 	.open = hwicap_open,
571 	.release = hwicap_release,
572 };
573 
574 static int __devinit hwicap_setup(struct device *dev, int id,
575 		const struct resource *regs_res,
576 		const struct hwicap_driver_config *config,
577 		const struct config_registers *config_regs)
578 {
579 	dev_t devt;
580 	struct hwicap_drvdata *drvdata = NULL;
581 	int retval = 0;
582 
583 	dev_info(dev, "Xilinx icap port driver\n");
584 
585 	mutex_lock(&icap_sem);
586 
587 	if (id < 0) {
588 		for (id = 0; id < HWICAP_DEVICES; id++)
589 			if (!probed_devices[id])
590 				break;
591 	}
592 	if (id < 0 || id >= HWICAP_DEVICES) {
593 		mutex_unlock(&icap_sem);
594 		dev_err(dev, "%s%i too large\n", DRIVER_NAME, id);
595 		return -EINVAL;
596 	}
597 	if (probed_devices[id]) {
598 		mutex_unlock(&icap_sem);
599 		dev_err(dev, "cannot assign to %s%i; it is already in use\n",
600 			DRIVER_NAME, id);
601 		return -EBUSY;
602 	}
603 
604 	probed_devices[id] = 1;
605 	mutex_unlock(&icap_sem);
606 
607 	devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR + id);
608 
609 	drvdata = kzalloc(sizeof(struct hwicap_drvdata), GFP_KERNEL);
610 	if (!drvdata) {
611 		dev_err(dev, "Couldn't allocate device private record\n");
612 		retval = -ENOMEM;
613 		goto failed0;
614 	}
615 	dev_set_drvdata(dev, (void *)drvdata);
616 
617 	if (!regs_res) {
618 		dev_err(dev, "Couldn't get registers resource\n");
619 		retval = -EFAULT;
620 		goto failed1;
621 	}
622 
623 	drvdata->mem_start = regs_res->start;
624 	drvdata->mem_end = regs_res->end;
625 	drvdata->mem_size = regs_res->end - regs_res->start + 1;
626 
627 	if (!request_mem_region(drvdata->mem_start,
628 					drvdata->mem_size, DRIVER_NAME)) {
629 		dev_err(dev, "Couldn't lock memory region at %Lx\n",
630 			regs_res->start);
631 		retval = -EBUSY;
632 		goto failed1;
633 	}
634 
635 	drvdata->devt = devt;
636 	drvdata->dev = dev;
637 	drvdata->base_address = ioremap(drvdata->mem_start, drvdata->mem_size);
638 	if (!drvdata->base_address) {
639 		dev_err(dev, "ioremap() failed\n");
640 		goto failed2;
641 	}
642 
643 	drvdata->config = config;
644 	drvdata->config_regs = config_regs;
645 
646 	mutex_init(&drvdata->sem);
647 	drvdata->is_open = 0;
648 
649 	dev_info(dev, "ioremap %lx to %p with size %Lx\n",
650 		 (unsigned long int)drvdata->mem_start,
651 			drvdata->base_address, drvdata->mem_size);
652 
653 	cdev_init(&drvdata->cdev, &hwicap_fops);
654 	drvdata->cdev.owner = THIS_MODULE;
655 	retval = cdev_add(&drvdata->cdev, devt, 1);
656 	if (retval) {
657 		dev_err(dev, "cdev_add() failed\n");
658 		goto failed3;
659 	}
660 
661 	device_create_drvdata(icap_class, dev, devt, NULL,
662 			      "%s%d", DRIVER_NAME, id);
663 	return 0;		/* success */
664 
665  failed3:
666 	iounmap(drvdata->base_address);
667 
668  failed2:
669 	release_mem_region(regs_res->start, drvdata->mem_size);
670 
671  failed1:
672 	kfree(drvdata);
673 
674  failed0:
675 	mutex_lock(&icap_sem);
676 	probed_devices[id] = 0;
677 	mutex_unlock(&icap_sem);
678 
679 	return retval;
680 }
681 
682 static struct hwicap_driver_config buffer_icap_config = {
683 	.get_configuration = buffer_icap_get_configuration,
684 	.set_configuration = buffer_icap_set_configuration,
685 	.get_status = buffer_icap_get_status,
686 	.reset = buffer_icap_reset,
687 };
688 
689 static struct hwicap_driver_config fifo_icap_config = {
690 	.get_configuration = fifo_icap_get_configuration,
691 	.set_configuration = fifo_icap_set_configuration,
692 	.get_status = fifo_icap_get_status,
693 	.reset = fifo_icap_reset,
694 };
695 
696 static int __devexit hwicap_remove(struct device *dev)
697 {
698 	struct hwicap_drvdata *drvdata;
699 
700 	drvdata = (struct hwicap_drvdata *)dev_get_drvdata(dev);
701 
702 	if (!drvdata)
703 		return 0;
704 
705 	device_destroy(icap_class, drvdata->devt);
706 	cdev_del(&drvdata->cdev);
707 	iounmap(drvdata->base_address);
708 	release_mem_region(drvdata->mem_start, drvdata->mem_size);
709 	kfree(drvdata);
710 	dev_set_drvdata(dev, NULL);
711 
712 	mutex_lock(&icap_sem);
713 	probed_devices[MINOR(dev->devt)-XHWICAP_MINOR] = 0;
714 	mutex_unlock(&icap_sem);
715 	return 0;		/* success */
716 }
717 
718 static int __devinit hwicap_drv_probe(struct platform_device *pdev)
719 {
720 	struct resource *res;
721 	const struct config_registers *regs;
722 	const char *family;
723 
724 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
725 	if (!res)
726 		return -ENODEV;
727 
728 	/* It's most likely that we're using V4, if the family is not
729 	   specified */
730 	regs = &v4_config_registers;
731 	family = pdev->dev.platform_data;
732 
733 	if (family) {
734 		if (!strcmp(family, "virtex2p")) {
735 			regs = &v2_config_registers;
736 		} else if (!strcmp(family, "virtex4")) {
737 			regs = &v4_config_registers;
738 		} else if (!strcmp(family, "virtex5")) {
739 			regs = &v5_config_registers;
740 		}
741 	}
742 
743 	return hwicap_setup(&pdev->dev, pdev->id, res,
744 			&buffer_icap_config, regs);
745 }
746 
747 static int __devexit hwicap_drv_remove(struct platform_device *pdev)
748 {
749 	return hwicap_remove(&pdev->dev);
750 }
751 
752 static struct platform_driver hwicap_platform_driver = {
753 	.probe = hwicap_drv_probe,
754 	.remove = hwicap_drv_remove,
755 	.driver = {
756 		.owner = THIS_MODULE,
757 		.name = DRIVER_NAME,
758 	},
759 };
760 
761 /* ---------------------------------------------------------------------
762  * OF bus binding
763  */
764 
765 #if defined(CONFIG_OF)
766 static int __devinit
767 hwicap_of_probe(struct of_device *op, const struct of_device_id *match)
768 {
769 	struct resource res;
770 	const unsigned int *id;
771 	const char *family;
772 	int rc;
773 	const struct hwicap_driver_config *config = match->data;
774 	const struct config_registers *regs;
775 
776 	dev_dbg(&op->dev, "hwicap_of_probe(%p, %p)\n", op, match);
777 
778 	rc = of_address_to_resource(op->node, 0, &res);
779 	if (rc) {
780 		dev_err(&op->dev, "invalid address\n");
781 		return rc;
782 	}
783 
784 	id = of_get_property(op->node, "port-number", NULL);
785 
786 	/* It's most likely that we're using V4, if the family is not
787 	   specified */
788 	regs = &v4_config_registers;
789 	family = of_get_property(op->node, "xlnx,family", NULL);
790 
791 	if (family) {
792 		if (!strcmp(family, "virtex2p")) {
793 			regs = &v2_config_registers;
794 		} else if (!strcmp(family, "virtex4")) {
795 			regs = &v4_config_registers;
796 		} else if (!strcmp(family, "virtex5")) {
797 			regs = &v5_config_registers;
798 		}
799 	}
800 	return hwicap_setup(&op->dev, id ? *id : -1, &res, config,
801 			regs);
802 }
803 
804 static int __devexit hwicap_of_remove(struct of_device *op)
805 {
806 	return hwicap_remove(&op->dev);
807 }
808 
809 /* Match table for of_platform binding */
810 static const struct of_device_id __devinitconst hwicap_of_match[] = {
811 	{ .compatible = "xlnx,opb-hwicap-1.00.b", .data = &buffer_icap_config},
812 	{ .compatible = "xlnx,xps-hwicap-1.00.a", .data = &fifo_icap_config},
813 	{},
814 };
815 MODULE_DEVICE_TABLE(of, hwicap_of_match);
816 
817 static struct of_platform_driver hwicap_of_driver = {
818 	.owner = THIS_MODULE,
819 	.name = DRIVER_NAME,
820 	.match_table = hwicap_of_match,
821 	.probe = hwicap_of_probe,
822 	.remove = __devexit_p(hwicap_of_remove),
823 	.driver = {
824 		.name = DRIVER_NAME,
825 	},
826 };
827 
828 /* Registration helpers to keep the number of #ifdefs to a minimum */
829 static inline int __init hwicap_of_register(void)
830 {
831 	pr_debug("hwicap: calling of_register_platform_driver()\n");
832 	return of_register_platform_driver(&hwicap_of_driver);
833 }
834 
835 static inline void __exit hwicap_of_unregister(void)
836 {
837 	of_unregister_platform_driver(&hwicap_of_driver);
838 }
839 #else /* CONFIG_OF */
840 /* CONFIG_OF not enabled; do nothing helpers */
841 static inline int __init hwicap_of_register(void) { return 0; }
842 static inline void __exit hwicap_of_unregister(void) { }
843 #endif /* CONFIG_OF */
844 
845 static int __init hwicap_module_init(void)
846 {
847 	dev_t devt;
848 	int retval;
849 
850 	icap_class = class_create(THIS_MODULE, "xilinx_config");
851 	mutex_init(&icap_sem);
852 
853 	devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR);
854 	retval = register_chrdev_region(devt,
855 					HWICAP_DEVICES,
856 					DRIVER_NAME);
857 	if (retval < 0)
858 		return retval;
859 
860 	retval = platform_driver_register(&hwicap_platform_driver);
861 
862 	if (retval)
863 		goto failed1;
864 
865 	retval = hwicap_of_register();
866 
867 	if (retval)
868 		goto failed2;
869 
870 	return retval;
871 
872  failed2:
873 	platform_driver_unregister(&hwicap_platform_driver);
874 
875  failed1:
876 	unregister_chrdev_region(devt, HWICAP_DEVICES);
877 
878 	return retval;
879 }
880 
881 static void __exit hwicap_module_cleanup(void)
882 {
883 	dev_t devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR);
884 
885 	class_destroy(icap_class);
886 
887 	platform_driver_unregister(&hwicap_platform_driver);
888 
889 	hwicap_of_unregister();
890 
891 	unregister_chrdev_region(devt, HWICAP_DEVICES);
892 }
893 
894 module_init(hwicap_module_init);
895 module_exit(hwicap_module_cleanup);
896 
897 MODULE_AUTHOR("Xilinx, Inc; Xilinx Research Labs Group");
898 MODULE_DESCRIPTION("Xilinx ICAP Port Driver");
899 MODULE_LICENSE("GPL");
900