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 * (c) Copyright 2002 Xilinx Inc., Systems Engineering Group
25 * (c) Copyright 2004 Xilinx Inc., Systems Engineering Group
26 * (c) Copyright 2007-2008 Xilinx Inc.
27 * All rights reserved.
29 * You should have received a copy of the GNU General Public License along
30 * with this program; if not, write to the Free Software Foundation, Inc.,
31 * 675 Mass Ave, Cambridge, MA 02139, USA.
33 *****************************************************************************/
36 * This is the code behind /dev/icap* -- it allows a user-space
37 * application to use the Xilinx ICAP subsystem.
39 * The following operations are possible:
41 * open open the port and initialize for access.
42 * release release port
43 * write Write a bitstream to the configuration processor.
44 * read Read a data stream from the configuration processor.
46 * After being opened, the port is initialized and accessed to avoid a
47 * corrupted first read which may occur with some hardware. The port
48 * is left in a desynched state, requiring that a synch sequence be
49 * transmitted before any valid configuration data. A user will have
50 * exclusive access to the device while it remains open, and the state
51 * of the ICAP cannot be guaranteed after the device is closed. Note
52 * that a complete reset of the core and the state of the ICAP cannot
53 * be performed on many versions of the cores, hence users of this
54 * device should avoid making inconsistent accesses to the device. In
55 * particular, accessing the read interface, without first generating
56 * a write containing a readback packet can leave the ICAP in an
59 * Note that in order to use the read interface, it is first necessary
60 * to write a request packet to the write interface. i.e., it is not
61 * possible to simply readback the bitstream (or any configuration
62 * bits) from a device without specifically requesting them first.
63 * The code to craft such packets is intended to be part of the
64 * user-space application code that uses this device. The simplest
65 * way to use this interface is simply:
67 * cp foo.bit /dev/icap0
69 * Note that unless foo.bit is an appropriately constructed partial
70 * bitstream, this has a high likelihood of overwriting the design
71 * currently programmed in the FPGA.
74 #include <linux/module.h>
75 #include <linux/kernel.h>
76 #include <linux/types.h>
77 #include <linux/ioport.h>
78 #include <linux/interrupt.h>
79 #include <linux/fcntl.h>
80 #include <linux/init.h>
81 #include <linux/poll.h>
82 #include <linux/proc_fs.h>
83 #include <linux/mutex.h>
84 #include <linux/sysctl.h>
86 #include <linux/cdev.h>
87 #include <linux/platform_device.h>
88 #include <linux/slab.h>
91 #include <asm/uaccess.h>
94 /* For open firmware. */
95 #include <linux/of_address.h>
96 #include <linux/of_device.h>
97 #include <linux/of_platform.h>
100 #include "xilinx_hwicap.h"
101 #include "buffer_icap.h"
102 #include "fifo_icap.h"
104 #define DRIVER_NAME "icap"
106 #define HWICAP_REGS (0x10000)
108 #define XHWICAP_MAJOR 259
109 #define XHWICAP_MINOR 0
110 #define HWICAP_DEVICES 1
112 /* An array, which is set to true when the device is registered. */
113 static DEFINE_MUTEX(hwicap_mutex);
114 static bool probed_devices[HWICAP_DEVICES];
115 static struct mutex icap_sem;
117 static struct class *icap_class;
119 #define UNIMPLEMENTED 0xFFFF
121 static const struct config_registers v2_config_registers = {
137 .AXSS = UNIMPLEMENTED,
138 .C0R_1 = UNIMPLEMENTED,
139 .CSOB = UNIMPLEMENTED,
140 .WBSTAR = UNIMPLEMENTED,
141 .TIMER = UNIMPLEMENTED,
142 .BOOTSTS = UNIMPLEMENTED,
143 .CTL_1 = UNIMPLEMENTED,
146 static const struct config_registers v4_config_registers = {
158 .FLR = UNIMPLEMENTED,
159 .KEY = UNIMPLEMENTED,
163 .C0R_1 = UNIMPLEMENTED,
164 .CSOB = UNIMPLEMENTED,
165 .WBSTAR = UNIMPLEMENTED,
166 .TIMER = UNIMPLEMENTED,
167 .BOOTSTS = UNIMPLEMENTED,
168 .CTL_1 = UNIMPLEMENTED,
171 static const struct config_registers v5_config_registers = {
183 .FLR = UNIMPLEMENTED,
184 .KEY = UNIMPLEMENTED,
196 static const struct config_registers v6_config_registers = {
208 .FLR = UNIMPLEMENTED,
209 .KEY = UNIMPLEMENTED,
222 * hwicap_command_desync - Send a DESYNC command to the ICAP port.
223 * @drvdata: a pointer to the drvdata.
225 * This command desynchronizes the ICAP After this command, a
226 * bitstream containing a NULL packet, followed by a SYNCH packet is
227 * required before the ICAP will recognize commands.
229 static int hwicap_command_desync(struct hwicap_drvdata *drvdata)
235 * Create the data to be written to the ICAP.
237 buffer[index++] = hwicap_type_1_write(drvdata->config_regs->CMD) | 1;
238 buffer[index++] = XHI_CMD_DESYNCH;
239 buffer[index++] = XHI_NOOP_PACKET;
240 buffer[index++] = XHI_NOOP_PACKET;
243 * Write the data to the FIFO and intiate the transfer of data present
244 * in the FIFO to the ICAP device.
246 return drvdata->config->set_configuration(drvdata,
251 * hwicap_get_configuration_register - Query a configuration register.
252 * @drvdata: a pointer to the drvdata.
253 * @reg: a constant which represents the configuration
254 * register value to be returned.
255 * Examples: XHI_IDCODE, XHI_FLR.
256 * @reg_data: returns the value of the register.
258 * Sends a query packet to the ICAP and then receives the response.
259 * The icap is left in Synched state.
261 static int hwicap_get_configuration_register(struct hwicap_drvdata *drvdata,
262 u32 reg, u32 *reg_data)
269 * Create the data to be written to the ICAP.
271 buffer[index++] = XHI_DUMMY_PACKET;
272 buffer[index++] = XHI_NOOP_PACKET;
273 buffer[index++] = XHI_SYNC_PACKET;
274 buffer[index++] = XHI_NOOP_PACKET;
275 buffer[index++] = XHI_NOOP_PACKET;
278 * Write the data to the FIFO and initiate the transfer of data present
279 * in the FIFO to the ICAP device.
281 status = drvdata->config->set_configuration(drvdata,
286 /* If the syncword was not found, then we need to start over. */
287 status = drvdata->config->get_status(drvdata);
288 if ((status & XHI_SR_DALIGN_MASK) != XHI_SR_DALIGN_MASK)
292 buffer[index++] = hwicap_type_1_read(reg) | 1;
293 buffer[index++] = XHI_NOOP_PACKET;
294 buffer[index++] = XHI_NOOP_PACKET;
297 * Write the data to the FIFO and intiate the transfer of data present
298 * in the FIFO to the ICAP device.
300 status = drvdata->config->set_configuration(drvdata,
306 * Read the configuration register
308 status = drvdata->config->get_configuration(drvdata, reg_data, 1);
315 static int hwicap_initialize_hwicap(struct hwicap_drvdata *drvdata)
320 dev_dbg(drvdata->dev, "initializing\n");
322 /* Abort any current transaction, to make sure we have the
323 * ICAP in a good state. */
324 dev_dbg(drvdata->dev, "Reset...\n");
325 drvdata->config->reset(drvdata);
327 dev_dbg(drvdata->dev, "Desync...\n");
328 status = hwicap_command_desync(drvdata);
332 /* Attempt to read the IDCODE from ICAP. This
333 * may not be returned correctly, due to the design of the
336 dev_dbg(drvdata->dev, "Reading IDCODE...\n");
337 status = hwicap_get_configuration_register(
338 drvdata, drvdata->config_regs->IDCODE, &idcode);
339 dev_dbg(drvdata->dev, "IDCODE = %x\n", idcode);
343 dev_dbg(drvdata->dev, "Desync...\n");
344 status = hwicap_command_desync(drvdata);
352 hwicap_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
354 struct hwicap_drvdata *drvdata = file->private_data;
355 ssize_t bytes_to_read = 0;
361 status = mutex_lock_interruptible(&drvdata->sem);
365 if (drvdata->read_buffer_in_use) {
366 /* If there are leftover bytes in the buffer, just */
367 /* return them and don't try to read more from the */
370 (count < drvdata->read_buffer_in_use) ? count :
371 drvdata->read_buffer_in_use;
373 /* Return the data currently in the read buffer. */
374 if (copy_to_user(buf, drvdata->read_buffer, bytes_to_read)) {
378 drvdata->read_buffer_in_use -= bytes_to_read;
379 memmove(drvdata->read_buffer,
380 drvdata->read_buffer + bytes_to_read,
383 /* Get new data from the ICAP, and return was was requested. */
384 kbuf = (u32 *) get_zeroed_page(GFP_KERNEL);
390 /* The ICAP device is only able to read complete */
391 /* words. If a number of bytes that do not correspond */
392 /* to complete words is requested, then we read enough */
393 /* words to get the required number of bytes, and then */
394 /* save the remaining bytes for the next read. */
396 /* Determine the number of words to read, rounding up */
398 words = ((count + 3) >> 2);
399 bytes_to_read = words << 2;
401 if (bytes_to_read > PAGE_SIZE)
402 bytes_to_read = PAGE_SIZE;
404 /* Ensure we only read a complete number of words. */
405 bytes_remaining = bytes_to_read & 3;
407 words = bytes_to_read >> 2;
409 status = drvdata->config->get_configuration(drvdata,
412 /* If we didn't read correctly, then bail out. */
414 free_page((unsigned long)kbuf);
418 /* If we fail to return the data to the user, then bail out. */
419 if (copy_to_user(buf, kbuf, bytes_to_read)) {
420 free_page((unsigned long)kbuf);
424 memcpy(drvdata->read_buffer,
427 drvdata->read_buffer_in_use = bytes_remaining;
428 free_page((unsigned long)kbuf);
430 status = bytes_to_read;
432 mutex_unlock(&drvdata->sem);
437 hwicap_write(struct file *file, const char __user *buf,
438 size_t count, loff_t *ppos)
440 struct hwicap_drvdata *drvdata = file->private_data;
442 ssize_t left = count;
447 status = mutex_lock_interruptible(&drvdata->sem);
451 left += drvdata->write_buffer_in_use;
453 /* Only write multiples of 4 bytes. */
459 kbuf = (u32 *) __get_free_page(GFP_KERNEL);
466 /* only write multiples of 4 bytes, so there might */
467 /* be as many as 3 bytes left (at the end). */
474 if (drvdata->write_buffer_in_use) {
475 memcpy(kbuf, drvdata->write_buffer,
476 drvdata->write_buffer_in_use);
478 (((char *)kbuf) + drvdata->write_buffer_in_use),
480 len - (drvdata->write_buffer_in_use))) {
481 free_page((unsigned long)kbuf);
486 if (copy_from_user(kbuf, buf + written, len)) {
487 free_page((unsigned long)kbuf);
493 status = drvdata->config->set_configuration(drvdata,
497 free_page((unsigned long)kbuf);
501 if (drvdata->write_buffer_in_use) {
502 len -= drvdata->write_buffer_in_use;
503 left -= drvdata->write_buffer_in_use;
504 drvdata->write_buffer_in_use = 0;
509 if ((left > 0) && (left < 4)) {
510 if (!copy_from_user(drvdata->write_buffer,
511 buf + written, left)) {
512 drvdata->write_buffer_in_use = left;
518 free_page((unsigned long)kbuf);
521 mutex_unlock(&drvdata->sem);
525 static int hwicap_open(struct inode *inode, struct file *file)
527 struct hwicap_drvdata *drvdata;
530 mutex_lock(&hwicap_mutex);
531 drvdata = container_of(inode->i_cdev, struct hwicap_drvdata, cdev);
533 status = mutex_lock_interruptible(&drvdata->sem);
537 if (drvdata->is_open) {
542 status = hwicap_initialize_hwicap(drvdata);
544 dev_err(drvdata->dev, "Failed to open file");
548 file->private_data = drvdata;
549 drvdata->write_buffer_in_use = 0;
550 drvdata->read_buffer_in_use = 0;
551 drvdata->is_open = 1;
554 mutex_unlock(&drvdata->sem);
556 mutex_unlock(&hwicap_mutex);
560 static int hwicap_release(struct inode *inode, struct file *file)
562 struct hwicap_drvdata *drvdata = file->private_data;
566 mutex_lock(&drvdata->sem);
568 if (drvdata->write_buffer_in_use) {
569 /* Flush write buffer. */
570 for (i = drvdata->write_buffer_in_use; i < 4; i++)
571 drvdata->write_buffer[i] = 0;
573 status = drvdata->config->set_configuration(drvdata,
574 (u32 *) drvdata->write_buffer, 1);
579 status = hwicap_command_desync(drvdata);
584 drvdata->is_open = 0;
585 mutex_unlock(&drvdata->sem);
589 static const struct file_operations hwicap_fops = {
590 .owner = THIS_MODULE,
591 .write = hwicap_write,
594 .release = hwicap_release,
595 .llseek = noop_llseek,
598 static int hwicap_setup(struct device *dev, int id,
599 const struct resource *regs_res,
600 const struct hwicap_driver_config *config,
601 const struct config_registers *config_regs)
604 struct hwicap_drvdata *drvdata = NULL;
607 dev_info(dev, "Xilinx icap port driver\n");
609 mutex_lock(&icap_sem);
612 for (id = 0; id < HWICAP_DEVICES; id++)
613 if (!probed_devices[id])
616 if (id < 0 || id >= HWICAP_DEVICES) {
617 mutex_unlock(&icap_sem);
618 dev_err(dev, "%s%i too large\n", DRIVER_NAME, id);
621 if (probed_devices[id]) {
622 mutex_unlock(&icap_sem);
623 dev_err(dev, "cannot assign to %s%i; it is already in use\n",
628 probed_devices[id] = 1;
629 mutex_unlock(&icap_sem);
631 devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR + id);
633 drvdata = kzalloc(sizeof(struct hwicap_drvdata), GFP_KERNEL);
635 dev_err(dev, "Couldn't allocate device private record\n");
639 dev_set_drvdata(dev, (void *)drvdata);
642 dev_err(dev, "Couldn't get registers resource\n");
647 drvdata->mem_start = regs_res->start;
648 drvdata->mem_end = regs_res->end;
649 drvdata->mem_size = resource_size(regs_res);
651 if (!request_mem_region(drvdata->mem_start,
652 drvdata->mem_size, DRIVER_NAME)) {
653 dev_err(dev, "Couldn't lock memory region at %Lx\n",
654 (unsigned long long) regs_res->start);
659 drvdata->devt = devt;
661 drvdata->base_address = ioremap(drvdata->mem_start, drvdata->mem_size);
662 if (!drvdata->base_address) {
663 dev_err(dev, "ioremap() failed\n");
667 drvdata->config = config;
668 drvdata->config_regs = config_regs;
670 mutex_init(&drvdata->sem);
671 drvdata->is_open = 0;
673 dev_info(dev, "ioremap %llx to %p with size %llx\n",
674 (unsigned long long) drvdata->mem_start,
675 drvdata->base_address,
676 (unsigned long long) drvdata->mem_size);
678 cdev_init(&drvdata->cdev, &hwicap_fops);
679 drvdata->cdev.owner = THIS_MODULE;
680 retval = cdev_add(&drvdata->cdev, devt, 1);
682 dev_err(dev, "cdev_add() failed\n");
686 device_create(icap_class, dev, devt, NULL, "%s%d", DRIVER_NAME, id);
687 return 0; /* success */
690 iounmap(drvdata->base_address);
693 release_mem_region(regs_res->start, drvdata->mem_size);
699 mutex_lock(&icap_sem);
700 probed_devices[id] = 0;
701 mutex_unlock(&icap_sem);
706 static struct hwicap_driver_config buffer_icap_config = {
707 .get_configuration = buffer_icap_get_configuration,
708 .set_configuration = buffer_icap_set_configuration,
709 .get_status = buffer_icap_get_status,
710 .reset = buffer_icap_reset,
713 static struct hwicap_driver_config fifo_icap_config = {
714 .get_configuration = fifo_icap_get_configuration,
715 .set_configuration = fifo_icap_set_configuration,
716 .get_status = fifo_icap_get_status,
717 .reset = fifo_icap_reset,
720 static int hwicap_remove(struct device *dev)
722 struct hwicap_drvdata *drvdata;
724 drvdata = dev_get_drvdata(dev);
729 device_destroy(icap_class, drvdata->devt);
730 cdev_del(&drvdata->cdev);
731 iounmap(drvdata->base_address);
732 release_mem_region(drvdata->mem_start, drvdata->mem_size);
735 mutex_lock(&icap_sem);
736 probed_devices[MINOR(dev->devt)-XHWICAP_MINOR] = 0;
737 mutex_unlock(&icap_sem);
738 return 0; /* success */
742 static int hwicap_of_probe(struct platform_device *op,
743 const struct hwicap_driver_config *config)
746 const unsigned int *id;
749 const struct config_registers *regs;
752 rc = of_address_to_resource(op->dev.of_node, 0, &res);
754 dev_err(&op->dev, "invalid address\n");
758 id = of_get_property(op->dev.of_node, "port-number", NULL);
760 /* It's most likely that we're using V4, if the family is not
762 regs = &v4_config_registers;
763 family = of_get_property(op->dev.of_node, "xlnx,family", NULL);
766 if (!strcmp(family, "virtex2p")) {
767 regs = &v2_config_registers;
768 } else if (!strcmp(family, "virtex4")) {
769 regs = &v4_config_registers;
770 } else if (!strcmp(family, "virtex5")) {
771 regs = &v5_config_registers;
772 } else if (!strcmp(family, "virtex6")) {
773 regs = &v6_config_registers;
776 return hwicap_setup(&op->dev, id ? *id : -1, &res, config,
780 static inline int hwicap_of_probe(struct platform_device *op,
781 const struct hwicap_driver_config *config)
785 #endif /* CONFIG_OF */
787 static const struct of_device_id hwicap_of_match[];
788 static int hwicap_drv_probe(struct platform_device *pdev)
790 const struct of_device_id *match;
791 struct resource *res;
792 const struct config_registers *regs;
795 match = of_match_device(hwicap_of_match, &pdev->dev);
797 return hwicap_of_probe(pdev, match->data);
799 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
803 /* It's most likely that we're using V4, if the family is not
805 regs = &v4_config_registers;
806 family = pdev->dev.platform_data;
809 if (!strcmp(family, "virtex2p")) {
810 regs = &v2_config_registers;
811 } else if (!strcmp(family, "virtex4")) {
812 regs = &v4_config_registers;
813 } else if (!strcmp(family, "virtex5")) {
814 regs = &v5_config_registers;
815 } else if (!strcmp(family, "virtex6")) {
816 regs = &v6_config_registers;
820 return hwicap_setup(&pdev->dev, pdev->id, res,
821 &buffer_icap_config, regs);
824 static int hwicap_drv_remove(struct platform_device *pdev)
826 return hwicap_remove(&pdev->dev);
830 /* Match table for device tree binding */
831 static const struct of_device_id hwicap_of_match[] = {
832 { .compatible = "xlnx,opb-hwicap-1.00.b", .data = &buffer_icap_config},
833 { .compatible = "xlnx,xps-hwicap-1.00.a", .data = &fifo_icap_config},
836 MODULE_DEVICE_TABLE(of, hwicap_of_match);
838 #define hwicap_of_match NULL
841 static struct platform_driver hwicap_platform_driver = {
842 .probe = hwicap_drv_probe,
843 .remove = hwicap_drv_remove,
845 .owner = THIS_MODULE,
847 .of_match_table = hwicap_of_match,
851 static int __init hwicap_module_init(void)
856 icap_class = class_create(THIS_MODULE, "xilinx_config");
857 mutex_init(&icap_sem);
859 devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR);
860 retval = register_chrdev_region(devt,
866 retval = platform_driver_register(&hwicap_platform_driver);
873 unregister_chrdev_region(devt, HWICAP_DEVICES);
878 static void __exit hwicap_module_cleanup(void)
880 dev_t devt = MKDEV(XHWICAP_MAJOR, XHWICAP_MINOR);
882 class_destroy(icap_class);
884 platform_driver_unregister(&hwicap_platform_driver);
886 unregister_chrdev_region(devt, HWICAP_DEVICES);
889 module_init(hwicap_module_init);
890 module_exit(hwicap_module_cleanup);
892 MODULE_AUTHOR("Xilinx, Inc; Xilinx Research Labs Group");
893 MODULE_DESCRIPTION("Xilinx ICAP Port Driver");
894 MODULE_LICENSE("GPL");