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/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>
91 #include <linux/cdev.h>
92 #include <linux/platform_device.h>
95 #include <asm/uaccess.h>
96 #include <asm/system.h>
99 /* For open firmware. */
100 #include <linux/of_device.h>
101 #include <linux/of_platform.h>
104 #include "xilinx_hwicap.h"
105 #include "buffer_icap.h"
106 #include "fifo_icap.h"
108 #define DRIVER_NAME "icap"
110 #define HWICAP_REGS (0x10000)
112 #define XHWICAP_MAJOR 259
113 #define XHWICAP_MINOR 0
114 #define HWICAP_DEVICES 1
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;
120 static struct class *icap_class;
122 #define UNIMPLEMENTED 0xFFFF
124 static const struct config_registers v2_config_registers = {
140 .AXSS = UNIMPLEMENTED,
141 .C0R_1 = UNIMPLEMENTED,
142 .CSOB = UNIMPLEMENTED,
143 .WBSTAR = UNIMPLEMENTED,
144 .TIMER = UNIMPLEMENTED,
145 .BOOTSTS = UNIMPLEMENTED,
146 .CTL_1 = UNIMPLEMENTED,
149 static const struct config_registers v4_config_registers = {
161 .FLR = UNIMPLEMENTED,
162 .KEY = UNIMPLEMENTED,
166 .C0R_1 = UNIMPLEMENTED,
167 .CSOB = UNIMPLEMENTED,
168 .WBSTAR = UNIMPLEMENTED,
169 .TIMER = UNIMPLEMENTED,
170 .BOOTSTS = UNIMPLEMENTED,
171 .CTL_1 = UNIMPLEMENTED,
173 static const struct config_registers v5_config_registers = {
185 .FLR = UNIMPLEMENTED,
186 .KEY = UNIMPLEMENTED,
199 * hwicap_command_desync - Send a DESYNC command to the ICAP port.
200 * @drvdata: a pointer to the drvdata.
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.
206 static int hwicap_command_desync(struct hwicap_drvdata *drvdata)
212 * Create the data to be written to the ICAP.
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;
220 * Write the data to the FIFO and intiate the transfer of data present
221 * in the FIFO to the ICAP device.
223 return drvdata->config->set_configuration(drvdata,
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.
235 * Sends a query packet to the ICAP and then receives the response.
236 * The icap is left in Synched state.
238 static int hwicap_get_configuration_register(struct hwicap_drvdata *drvdata,
239 u32 reg, u32 *reg_data)
246 * Create the data to be written to the ICAP.
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;
255 * Write the data to the FIFO and initiate the transfer of data present
256 * in the FIFO to the ICAP device.
258 status = drvdata->config->set_configuration(drvdata,
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)
269 buffer[index++] = hwicap_type_1_read(reg) | 1;
270 buffer[index++] = XHI_NOOP_PACKET;
271 buffer[index++] = XHI_NOOP_PACKET;
274 * Write the data to the FIFO and intiate the transfer of data present
275 * in the FIFO to the ICAP device.
277 status = drvdata->config->set_configuration(drvdata,
283 * Read the configuration register
285 status = drvdata->config->get_configuration(drvdata, reg_data, 1);
292 static int hwicap_initialize_hwicap(struct hwicap_drvdata *drvdata)
297 dev_dbg(drvdata->dev, "initializing\n");
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);
304 dev_dbg(drvdata->dev, "Desync...\n");
305 status = hwicap_command_desync(drvdata);
309 /* Attempt to read the IDCODE from ICAP. This
310 * may not be returned correctly, due to the design of the
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);
320 dev_dbg(drvdata->dev, "Desync...\n");
321 status = hwicap_command_desync(drvdata);
329 hwicap_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
331 struct hwicap_drvdata *drvdata = file->private_data;
332 ssize_t bytes_to_read = 0;
338 status = mutex_lock_interruptible(&drvdata->sem);
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 */
347 (count < drvdata->read_buffer_in_use) ? count :
348 drvdata->read_buffer_in_use;
350 /* Return the data currently in the read buffer. */
351 if (copy_to_user(buf, drvdata->read_buffer, bytes_to_read)) {
355 drvdata->read_buffer_in_use -= bytes_to_read;
356 memmove(drvdata->read_buffer,
357 drvdata->read_buffer + bytes_to_read,
360 /* Get new data from the ICAP, and return was was requested. */
361 kbuf = (u32 *) get_zeroed_page(GFP_KERNEL);
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. */
373 /* Determine the number of words to read, rounding up */
375 words = ((count + 3) >> 2);
376 bytes_to_read = words << 2;
378 if (bytes_to_read > PAGE_SIZE)
379 bytes_to_read = PAGE_SIZE;
381 /* Ensure we only read a complete number of words. */
382 bytes_remaining = bytes_to_read & 3;
384 words = bytes_to_read >> 2;
386 status = drvdata->config->get_configuration(drvdata,
389 /* If we didn't read correctly, then bail out. */
391 free_page((unsigned long)kbuf);
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);
401 memcpy(drvdata->read_buffer,
404 drvdata->read_buffer_in_use = bytes_remaining;
405 free_page((unsigned long)kbuf);
407 status = bytes_to_read;
409 mutex_unlock(&drvdata->sem);
414 hwicap_write(struct file *file, const char __user *buf,
415 size_t count, loff_t *ppos)
417 struct hwicap_drvdata *drvdata = file->private_data;
419 ssize_t left = count;
424 status = mutex_lock_interruptible(&drvdata->sem);
428 left += drvdata->write_buffer_in_use;
430 /* Only write multiples of 4 bytes. */
436 kbuf = (u32 *) __get_free_page(GFP_KERNEL);
443 /* only write multiples of 4 bytes, so there might */
444 /* be as many as 3 bytes left (at the end). */
451 if (drvdata->write_buffer_in_use) {
452 memcpy(kbuf, drvdata->write_buffer,
453 drvdata->write_buffer_in_use);
455 (((char *)kbuf) + drvdata->write_buffer_in_use),
457 len - (drvdata->write_buffer_in_use))) {
458 free_page((unsigned long)kbuf);
463 if (copy_from_user(kbuf, buf + written, len)) {
464 free_page((unsigned long)kbuf);
470 status = drvdata->config->set_configuration(drvdata,
474 free_page((unsigned long)kbuf);
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;
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;
495 free_page((unsigned long)kbuf);
498 mutex_unlock(&drvdata->sem);
502 static int hwicap_open(struct inode *inode, struct file *file)
504 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);
534 static int hwicap_release(struct inode *inode, struct file *file)
536 struct hwicap_drvdata *drvdata = file->private_data;
540 mutex_lock(&drvdata->sem);
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;
547 status = drvdata->config->set_configuration(drvdata,
548 (u32 *) drvdata->write_buffer, 1);
553 status = hwicap_command_desync(drvdata);
558 drvdata->is_open = 0;
559 mutex_unlock(&drvdata->sem);
563 static struct file_operations hwicap_fops = {
564 .owner = THIS_MODULE,
565 .write = hwicap_write,
568 .release = hwicap_release,
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)
577 struct hwicap_drvdata *drvdata = NULL;
580 dev_info(dev, "Xilinx icap port driver\n");
582 mutex_lock(&icap_sem);
585 for (id = 0; id < HWICAP_DEVICES; id++)
586 if (!probed_devices[id])
589 if (id < 0 || id >= HWICAP_DEVICES) {
590 mutex_unlock(&icap_sem);
591 dev_err(dev, "%s%i too large\n", DRIVER_NAME, id);
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",
601 probed_devices[id] = 1;
602 mutex_unlock(&icap_sem);
604 devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR + id);
606 drvdata = kzalloc(sizeof(struct hwicap_drvdata), GFP_KERNEL);
608 dev_err(dev, "Couldn't allocate device private record\n");
612 dev_set_drvdata(dev, (void *)drvdata);
615 dev_err(dev, "Couldn't get registers resource\n");
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;
624 if (!request_mem_region(drvdata->mem_start,
625 drvdata->mem_size, DRIVER_NAME)) {
626 dev_err(dev, "Couldn't lock memory region at %p\n",
627 (void *)regs_res->start);
632 drvdata->devt = devt;
634 drvdata->base_address = ioremap(drvdata->mem_start, drvdata->mem_size);
635 if (!drvdata->base_address) {
636 dev_err(dev, "ioremap() failed\n");
640 drvdata->config = config;
641 drvdata->config_regs = config_regs;
643 mutex_init(&drvdata->sem);
644 drvdata->is_open = 0;
646 dev_info(dev, "ioremap %lx to %p with size %x\n",
647 (unsigned long int)drvdata->mem_start,
648 drvdata->base_address, drvdata->mem_size);
650 cdev_init(&drvdata->cdev, &hwicap_fops);
651 drvdata->cdev.owner = THIS_MODULE;
652 retval = cdev_add(&drvdata->cdev, devt, 1);
654 dev_err(dev, "cdev_add() failed\n");
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 */
662 iounmap(drvdata->base_address);
665 release_mem_region(regs_res->start, drvdata->mem_size);
671 mutex_lock(&icap_sem);
672 probed_devices[id] = 0;
673 mutex_unlock(&icap_sem);
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,
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,
692 static int __devexit hwicap_remove(struct device *dev)
694 struct hwicap_drvdata *drvdata;
696 drvdata = (struct hwicap_drvdata *)dev_get_drvdata(dev);
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);
706 dev_set_drvdata(dev, NULL);
708 mutex_lock(&icap_sem);
709 probed_devices[MINOR(dev->devt)-XHWICAP_MINOR] = 0;
710 mutex_unlock(&icap_sem);
711 return 0; /* success */
714 static int __devinit hwicap_drv_probe(struct platform_device *pdev)
716 struct resource *res;
717 const struct config_registers *regs;
720 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
724 /* It's most likely that we're using V4, if the family is not
726 regs = &v4_config_registers;
727 family = pdev->dev.platform_data;
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;
739 return hwicap_setup(&pdev->dev, pdev->id, res,
740 &buffer_icap_config, regs);
743 static int __devexit hwicap_drv_remove(struct platform_device *pdev)
745 return hwicap_remove(&pdev->dev);
748 static struct platform_driver hwicap_platform_driver = {
749 .probe = hwicap_drv_probe,
750 .remove = hwicap_drv_remove,
752 .owner = THIS_MODULE,
757 /* ---------------------------------------------------------------------
761 #if defined(CONFIG_OF)
763 hwicap_of_probe(struct of_device *op, const struct of_device_id *match)
766 const unsigned int *id;
769 const struct hwicap_driver_config *config = match->data;
770 const struct config_registers *regs;
772 dev_dbg(&op->dev, "hwicap_of_probe(%p, %p)\n", op, match);
774 rc = of_address_to_resource(op->node, 0, &res);
776 dev_err(&op->dev, "invalid address\n");
780 id = of_get_property(op->node, "port-number", NULL);
782 /* It's most likely that we're using V4, if the family is not
784 regs = &v4_config_registers;
785 family = of_get_property(op->node, "xlnx,family", NULL);
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;
796 return hwicap_setup(&op->dev, id ? *id : -1, &res, config,
800 static int __devexit hwicap_of_remove(struct of_device *op)
802 return hwicap_remove(&op->dev);
805 /* Match table for of_platform binding */
806 static const struct of_device_id __devinit 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},
811 MODULE_DEVICE_TABLE(of, hwicap_of_match);
813 static struct of_platform_driver hwicap_of_driver = {
814 .owner = THIS_MODULE,
816 .match_table = hwicap_of_match,
817 .probe = hwicap_of_probe,
818 .remove = __devexit_p(hwicap_of_remove),
824 /* Registration helpers to keep the number of #ifdefs to a minimum */
825 static inline int __init hwicap_of_register(void)
827 pr_debug("hwicap: calling of_register_platform_driver()\n");
828 return of_register_platform_driver(&hwicap_of_driver);
831 static inline void __exit hwicap_of_unregister(void)
833 of_unregister_platform_driver(&hwicap_of_driver);
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 */
841 static int __init hwicap_module_init(void)
846 icap_class = class_create(THIS_MODULE, "xilinx_config");
847 mutex_init(&icap_sem);
849 devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR);
850 retval = register_chrdev_region(devt,
856 retval = platform_driver_register(&hwicap_platform_driver);
861 retval = hwicap_of_register();
869 platform_driver_unregister(&hwicap_platform_driver);
872 unregister_chrdev_region(devt, HWICAP_DEVICES);
877 static void __exit hwicap_module_cleanup(void)
879 dev_t devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR);
881 class_destroy(icap_class);
883 platform_driver_unregister(&hwicap_platform_driver);
885 hwicap_of_unregister();
887 unregister_chrdev_region(devt, HWICAP_DEVICES);
890 module_init(hwicap_module_init);
891 module_exit(hwicap_module_cleanup);
893 MODULE_AUTHOR("Xilinx, Inc; Xilinx Research Labs Group");
894 MODULE_DESCRIPTION("Xilinx ICAP Port Driver");
895 MODULE_LICENSE("GPL");