1 /*****************************************************************************
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.
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.
24 * Xilinx products are not intended for use in life support appliances,
25 * devices, or systems. Use in such applications is expressly prohibited.
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.
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.
36 *****************************************************************************/
39 * This is the code behind /dev/icap* -- it allows a user-space
40 * application to use the Xilinx ICAP subsystem.
42 * The following operations are possible:
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.
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
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:
70 * cp foo.bit /dev/icap0
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.
77 #include <linux/module.h>
78 #include <linux/kernel.h>
79 #include <linux/types.h>
80 #include <linux/ioport.h>
81 #include <linux/interrupt.h>
82 #include <linux/fcntl.h>
83 #include <linux/init.h>
84 #include <linux/poll.h>
85 #include <linux/proc_fs.h>
86 #include <linux/mutex.h>
87 #include <linux/smp_lock.h>
88 #include <linux/sysctl.h>
90 #include <linux/cdev.h>
91 #include <linux/platform_device.h>
94 #include <asm/uaccess.h>
95 #include <asm/system.h>
98 /* For open firmware. */
99 #include <linux/of_device.h>
100 #include <linux/of_platform.h>
103 #include "xilinx_hwicap.h"
104 #include "buffer_icap.h"
105 #include "fifo_icap.h"
107 #define DRIVER_NAME "icap"
109 #define HWICAP_REGS (0x10000)
111 #define XHWICAP_MAJOR 259
112 #define XHWICAP_MINOR 0
113 #define HWICAP_DEVICES 1
115 /* An array, which is set to true when the device is registered. */
116 static bool probed_devices[HWICAP_DEVICES];
117 static struct mutex icap_sem;
119 static struct class *icap_class;
121 #define UNIMPLEMENTED 0xFFFF
123 static const struct config_registers v2_config_registers = {
139 .AXSS = UNIMPLEMENTED,
140 .C0R_1 = UNIMPLEMENTED,
141 .CSOB = UNIMPLEMENTED,
142 .WBSTAR = UNIMPLEMENTED,
143 .TIMER = UNIMPLEMENTED,
144 .BOOTSTS = UNIMPLEMENTED,
145 .CTL_1 = UNIMPLEMENTED,
148 static const struct config_registers v4_config_registers = {
160 .FLR = UNIMPLEMENTED,
161 .KEY = UNIMPLEMENTED,
165 .C0R_1 = UNIMPLEMENTED,
166 .CSOB = UNIMPLEMENTED,
167 .WBSTAR = UNIMPLEMENTED,
168 .TIMER = UNIMPLEMENTED,
169 .BOOTSTS = UNIMPLEMENTED,
170 .CTL_1 = UNIMPLEMENTED,
172 static const struct config_registers v5_config_registers = {
184 .FLR = UNIMPLEMENTED,
185 .KEY = UNIMPLEMENTED,
198 * hwicap_command_desync - Send a DESYNC command to the ICAP port.
199 * @drvdata: a pointer to the drvdata.
201 * This command desynchronizes the ICAP After this command, a
202 * bitstream containing a NULL packet, followed by a SYNCH packet is
203 * required before the ICAP will recognize commands.
205 static int hwicap_command_desync(struct hwicap_drvdata *drvdata)
211 * Create the data to be written to the ICAP.
213 buffer[index++] = hwicap_type_1_write(drvdata->config_regs->CMD) | 1;
214 buffer[index++] = XHI_CMD_DESYNCH;
215 buffer[index++] = XHI_NOOP_PACKET;
216 buffer[index++] = XHI_NOOP_PACKET;
219 * Write the data to the FIFO and intiate the transfer of data present
220 * in the FIFO to the ICAP device.
222 return drvdata->config->set_configuration(drvdata,
227 * hwicap_get_configuration_register - Query a configuration register.
228 * @drvdata: a pointer to the drvdata.
229 * @reg: a constant which represents the configuration
230 * register value to be returned.
231 * Examples: XHI_IDCODE, XHI_FLR.
232 * @reg_data: returns the value of the register.
234 * Sends a query packet to the ICAP and then receives the response.
235 * The icap is left in Synched state.
237 static int hwicap_get_configuration_register(struct hwicap_drvdata *drvdata,
238 u32 reg, u32 *reg_data)
245 * Create the data to be written to the ICAP.
247 buffer[index++] = XHI_DUMMY_PACKET;
248 buffer[index++] = XHI_NOOP_PACKET;
249 buffer[index++] = XHI_SYNC_PACKET;
250 buffer[index++] = XHI_NOOP_PACKET;
251 buffer[index++] = XHI_NOOP_PACKET;
254 * Write the data to the FIFO and initiate the transfer of data present
255 * in the FIFO to the ICAP device.
257 status = drvdata->config->set_configuration(drvdata,
262 /* If the syncword was not found, then we need to start over. */
263 status = drvdata->config->get_status(drvdata);
264 if ((status & XHI_SR_DALIGN_MASK) != XHI_SR_DALIGN_MASK)
268 buffer[index++] = hwicap_type_1_read(reg) | 1;
269 buffer[index++] = XHI_NOOP_PACKET;
270 buffer[index++] = XHI_NOOP_PACKET;
273 * Write the data to the FIFO and intiate the transfer of data present
274 * in the FIFO to the ICAP device.
276 status = drvdata->config->set_configuration(drvdata,
282 * Read the configuration register
284 status = drvdata->config->get_configuration(drvdata, reg_data, 1);
291 static int hwicap_initialize_hwicap(struct hwicap_drvdata *drvdata)
296 dev_dbg(drvdata->dev, "initializing\n");
298 /* Abort any current transaction, to make sure we have the
299 * ICAP in a good state. */
300 dev_dbg(drvdata->dev, "Reset...\n");
301 drvdata->config->reset(drvdata);
303 dev_dbg(drvdata->dev, "Desync...\n");
304 status = hwicap_command_desync(drvdata);
308 /* Attempt to read the IDCODE from ICAP. This
309 * may not be returned correctly, due to the design of the
312 dev_dbg(drvdata->dev, "Reading IDCODE...\n");
313 status = hwicap_get_configuration_register(
314 drvdata, drvdata->config_regs->IDCODE, &idcode);
315 dev_dbg(drvdata->dev, "IDCODE = %x\n", idcode);
319 dev_dbg(drvdata->dev, "Desync...\n");
320 status = hwicap_command_desync(drvdata);
328 hwicap_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
330 struct hwicap_drvdata *drvdata = file->private_data;
331 ssize_t bytes_to_read = 0;
337 status = mutex_lock_interruptible(&drvdata->sem);
341 if (drvdata->read_buffer_in_use) {
342 /* If there are leftover bytes in the buffer, just */
343 /* return them and don't try to read more from the */
346 (count < drvdata->read_buffer_in_use) ? count :
347 drvdata->read_buffer_in_use;
349 /* Return the data currently in the read buffer. */
350 if (copy_to_user(buf, drvdata->read_buffer, bytes_to_read)) {
354 drvdata->read_buffer_in_use -= bytes_to_read;
355 memmove(drvdata->read_buffer,
356 drvdata->read_buffer + bytes_to_read,
359 /* Get new data from the ICAP, and return was was requested. */
360 kbuf = (u32 *) get_zeroed_page(GFP_KERNEL);
366 /* The ICAP device is only able to read complete */
367 /* words. If a number of bytes that do not correspond */
368 /* to complete words is requested, then we read enough */
369 /* words to get the required number of bytes, and then */
370 /* save the remaining bytes for the next read. */
372 /* Determine the number of words to read, rounding up */
374 words = ((count + 3) >> 2);
375 bytes_to_read = words << 2;
377 if (bytes_to_read > PAGE_SIZE)
378 bytes_to_read = PAGE_SIZE;
380 /* Ensure we only read a complete number of words. */
381 bytes_remaining = bytes_to_read & 3;
383 words = bytes_to_read >> 2;
385 status = drvdata->config->get_configuration(drvdata,
388 /* If we didn't read correctly, then bail out. */
390 free_page((unsigned long)kbuf);
394 /* If we fail to return the data to the user, then bail out. */
395 if (copy_to_user(buf, kbuf, bytes_to_read)) {
396 free_page((unsigned long)kbuf);
400 memcpy(drvdata->read_buffer,
403 drvdata->read_buffer_in_use = bytes_remaining;
404 free_page((unsigned long)kbuf);
406 status = bytes_to_read;
408 mutex_unlock(&drvdata->sem);
413 hwicap_write(struct file *file, const char __user *buf,
414 size_t count, loff_t *ppos)
416 struct hwicap_drvdata *drvdata = file->private_data;
418 ssize_t left = count;
423 status = mutex_lock_interruptible(&drvdata->sem);
427 left += drvdata->write_buffer_in_use;
429 /* Only write multiples of 4 bytes. */
435 kbuf = (u32 *) __get_free_page(GFP_KERNEL);
442 /* only write multiples of 4 bytes, so there might */
443 /* be as many as 3 bytes left (at the end). */
450 if (drvdata->write_buffer_in_use) {
451 memcpy(kbuf, drvdata->write_buffer,
452 drvdata->write_buffer_in_use);
454 (((char *)kbuf) + drvdata->write_buffer_in_use),
456 len - (drvdata->write_buffer_in_use))) {
457 free_page((unsigned long)kbuf);
462 if (copy_from_user(kbuf, buf + written, len)) {
463 free_page((unsigned long)kbuf);
469 status = drvdata->config->set_configuration(drvdata,
473 free_page((unsigned long)kbuf);
477 if (drvdata->write_buffer_in_use) {
478 len -= drvdata->write_buffer_in_use;
479 left -= drvdata->write_buffer_in_use;
480 drvdata->write_buffer_in_use = 0;
485 if ((left > 0) && (left < 4)) {
486 if (!copy_from_user(drvdata->write_buffer,
487 buf + written, left)) {
488 drvdata->write_buffer_in_use = left;
494 free_page((unsigned long)kbuf);
497 mutex_unlock(&drvdata->sem);
501 static int hwicap_open(struct inode *inode, struct file *file)
503 struct hwicap_drvdata *drvdata;
507 drvdata = container_of(inode->i_cdev, struct hwicap_drvdata, cdev);
509 status = mutex_lock_interruptible(&drvdata->sem);
513 if (drvdata->is_open) {
518 status = hwicap_initialize_hwicap(drvdata);
520 dev_err(drvdata->dev, "Failed to open file");
524 file->private_data = drvdata;
525 drvdata->write_buffer_in_use = 0;
526 drvdata->read_buffer_in_use = 0;
527 drvdata->is_open = 1;
530 mutex_unlock(&drvdata->sem);
536 static int hwicap_release(struct inode *inode, struct file *file)
538 struct hwicap_drvdata *drvdata = file->private_data;
542 mutex_lock(&drvdata->sem);
544 if (drvdata->write_buffer_in_use) {
545 /* Flush write buffer. */
546 for (i = drvdata->write_buffer_in_use; i < 4; i++)
547 drvdata->write_buffer[i] = 0;
549 status = drvdata->config->set_configuration(drvdata,
550 (u32 *) drvdata->write_buffer, 1);
555 status = hwicap_command_desync(drvdata);
560 drvdata->is_open = 0;
561 mutex_unlock(&drvdata->sem);
565 static struct file_operations hwicap_fops = {
566 .owner = THIS_MODULE,
567 .write = hwicap_write,
570 .release = hwicap_release,
573 static int __devinit hwicap_setup(struct device *dev, int id,
574 const struct resource *regs_res,
575 const struct hwicap_driver_config *config,
576 const struct config_registers *config_regs)
579 struct hwicap_drvdata *drvdata = NULL;
582 dev_info(dev, "Xilinx icap port driver\n");
584 mutex_lock(&icap_sem);
587 for (id = 0; id < HWICAP_DEVICES; id++)
588 if (!probed_devices[id])
591 if (id < 0 || id >= HWICAP_DEVICES) {
592 mutex_unlock(&icap_sem);
593 dev_err(dev, "%s%i too large\n", DRIVER_NAME, id);
596 if (probed_devices[id]) {
597 mutex_unlock(&icap_sem);
598 dev_err(dev, "cannot assign to %s%i; it is already in use\n",
603 probed_devices[id] = 1;
604 mutex_unlock(&icap_sem);
606 devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR + id);
608 drvdata = kzalloc(sizeof(struct hwicap_drvdata), GFP_KERNEL);
610 dev_err(dev, "Couldn't allocate device private record\n");
614 dev_set_drvdata(dev, (void *)drvdata);
617 dev_err(dev, "Couldn't get registers resource\n");
622 drvdata->mem_start = regs_res->start;
623 drvdata->mem_end = regs_res->end;
624 drvdata->mem_size = regs_res->end - regs_res->start + 1;
626 if (!request_mem_region(drvdata->mem_start,
627 drvdata->mem_size, DRIVER_NAME)) {
628 dev_err(dev, "Couldn't lock memory region at %Lx\n",
634 drvdata->devt = devt;
636 drvdata->base_address = ioremap(drvdata->mem_start, drvdata->mem_size);
637 if (!drvdata->base_address) {
638 dev_err(dev, "ioremap() failed\n");
642 drvdata->config = config;
643 drvdata->config_regs = config_regs;
645 mutex_init(&drvdata->sem);
646 drvdata->is_open = 0;
648 dev_info(dev, "ioremap %lx to %p with size %Lx\n",
649 (unsigned long int)drvdata->mem_start,
650 drvdata->base_address, drvdata->mem_size);
652 cdev_init(&drvdata->cdev, &hwicap_fops);
653 drvdata->cdev.owner = THIS_MODULE;
654 retval = cdev_add(&drvdata->cdev, devt, 1);
656 dev_err(dev, "cdev_add() failed\n");
660 device_create_drvdata(icap_class, dev, devt, NULL,
661 "%s%d", DRIVER_NAME, id);
662 return 0; /* success */
665 iounmap(drvdata->base_address);
668 release_mem_region(regs_res->start, drvdata->mem_size);
674 mutex_lock(&icap_sem);
675 probed_devices[id] = 0;
676 mutex_unlock(&icap_sem);
681 static struct hwicap_driver_config buffer_icap_config = {
682 .get_configuration = buffer_icap_get_configuration,
683 .set_configuration = buffer_icap_set_configuration,
684 .get_status = buffer_icap_get_status,
685 .reset = buffer_icap_reset,
688 static struct hwicap_driver_config fifo_icap_config = {
689 .get_configuration = fifo_icap_get_configuration,
690 .set_configuration = fifo_icap_set_configuration,
691 .get_status = fifo_icap_get_status,
692 .reset = fifo_icap_reset,
695 static int __devexit hwicap_remove(struct device *dev)
697 struct hwicap_drvdata *drvdata;
699 drvdata = (struct hwicap_drvdata *)dev_get_drvdata(dev);
704 device_destroy(icap_class, drvdata->devt);
705 cdev_del(&drvdata->cdev);
706 iounmap(drvdata->base_address);
707 release_mem_region(drvdata->mem_start, drvdata->mem_size);
709 dev_set_drvdata(dev, NULL);
711 mutex_lock(&icap_sem);
712 probed_devices[MINOR(dev->devt)-XHWICAP_MINOR] = 0;
713 mutex_unlock(&icap_sem);
714 return 0; /* success */
717 static int __devinit hwicap_drv_probe(struct platform_device *pdev)
719 struct resource *res;
720 const struct config_registers *regs;
723 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
727 /* It's most likely that we're using V4, if the family is not
729 regs = &v4_config_registers;
730 family = pdev->dev.platform_data;
733 if (!strcmp(family, "virtex2p")) {
734 regs = &v2_config_registers;
735 } else if (!strcmp(family, "virtex4")) {
736 regs = &v4_config_registers;
737 } else if (!strcmp(family, "virtex5")) {
738 regs = &v5_config_registers;
742 return hwicap_setup(&pdev->dev, pdev->id, res,
743 &buffer_icap_config, regs);
746 static int __devexit hwicap_drv_remove(struct platform_device *pdev)
748 return hwicap_remove(&pdev->dev);
751 static struct platform_driver hwicap_platform_driver = {
752 .probe = hwicap_drv_probe,
753 .remove = hwicap_drv_remove,
755 .owner = THIS_MODULE,
760 /* ---------------------------------------------------------------------
764 #if defined(CONFIG_OF)
766 hwicap_of_probe(struct of_device *op, const struct of_device_id *match)
769 const unsigned int *id;
772 const struct hwicap_driver_config *config = match->data;
773 const struct config_registers *regs;
775 dev_dbg(&op->dev, "hwicap_of_probe(%p, %p)\n", op, match);
777 rc = of_address_to_resource(op->node, 0, &res);
779 dev_err(&op->dev, "invalid address\n");
783 id = of_get_property(op->node, "port-number", NULL);
785 /* It's most likely that we're using V4, if the family is not
787 regs = &v4_config_registers;
788 family = of_get_property(op->node, "xlnx,family", NULL);
791 if (!strcmp(family, "virtex2p")) {
792 regs = &v2_config_registers;
793 } else if (!strcmp(family, "virtex4")) {
794 regs = &v4_config_registers;
795 } else if (!strcmp(family, "virtex5")) {
796 regs = &v5_config_registers;
799 return hwicap_setup(&op->dev, id ? *id : -1, &res, config,
803 static int __devexit hwicap_of_remove(struct of_device *op)
805 return hwicap_remove(&op->dev);
808 /* Match table for of_platform binding */
809 static const struct of_device_id __devinitconst hwicap_of_match[] = {
810 { .compatible = "xlnx,opb-hwicap-1.00.b", .data = &buffer_icap_config},
811 { .compatible = "xlnx,xps-hwicap-1.00.a", .data = &fifo_icap_config},
814 MODULE_DEVICE_TABLE(of, hwicap_of_match);
816 static struct of_platform_driver hwicap_of_driver = {
817 .owner = THIS_MODULE,
819 .match_table = hwicap_of_match,
820 .probe = hwicap_of_probe,
821 .remove = __devexit_p(hwicap_of_remove),
827 /* Registration helpers to keep the number of #ifdefs to a minimum */
828 static inline int __init hwicap_of_register(void)
830 pr_debug("hwicap: calling of_register_platform_driver()\n");
831 return of_register_platform_driver(&hwicap_of_driver);
834 static inline void __exit hwicap_of_unregister(void)
836 of_unregister_platform_driver(&hwicap_of_driver);
838 #else /* CONFIG_OF */
839 /* CONFIG_OF not enabled; do nothing helpers */
840 static inline int __init hwicap_of_register(void) { return 0; }
841 static inline void __exit hwicap_of_unregister(void) { }
842 #endif /* CONFIG_OF */
844 static int __init hwicap_module_init(void)
849 icap_class = class_create(THIS_MODULE, "xilinx_config");
850 mutex_init(&icap_sem);
852 devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR);
853 retval = register_chrdev_region(devt,
859 retval = platform_driver_register(&hwicap_platform_driver);
864 retval = hwicap_of_register();
872 platform_driver_unregister(&hwicap_platform_driver);
875 unregister_chrdev_region(devt, HWICAP_DEVICES);
880 static void __exit hwicap_module_cleanup(void)
882 dev_t devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR);
884 class_destroy(icap_class);
886 platform_driver_unregister(&hwicap_platform_driver);
888 hwicap_of_unregister();
890 unregister_chrdev_region(devt, HWICAP_DEVICES);
893 module_init(hwicap_module_init);
894 module_exit(hwicap_module_cleanup);
896 MODULE_AUTHOR("Xilinx, Inc; Xilinx Research Labs Group");
897 MODULE_DESCRIPTION("Xilinx ICAP Port Driver");
898 MODULE_LICENSE("GPL");