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 likelyhood 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/smp_lock.h>
85 #include <linux/sysctl.h>
87 #include <linux/cdev.h>
88 #include <linux/platform_device.h>
91 #include <asm/uaccess.h>
92 #include <asm/system.h>
95 /* For open firmware. */
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 bool probed_devices
[HWICAP_DEVICES
];
114 static struct mutex icap_sem
;
116 static struct class *icap_class
;
118 #define UNIMPLEMENTED 0xFFFF
120 static const struct config_registers v2_config_registers
= {
136 .AXSS
= UNIMPLEMENTED
,
137 .C0R_1
= UNIMPLEMENTED
,
138 .CSOB
= UNIMPLEMENTED
,
139 .WBSTAR
= UNIMPLEMENTED
,
140 .TIMER
= UNIMPLEMENTED
,
141 .BOOTSTS
= UNIMPLEMENTED
,
142 .CTL_1
= UNIMPLEMENTED
,
145 static const struct config_registers v4_config_registers
= {
157 .FLR
= UNIMPLEMENTED
,
158 .KEY
= UNIMPLEMENTED
,
162 .C0R_1
= UNIMPLEMENTED
,
163 .CSOB
= UNIMPLEMENTED
,
164 .WBSTAR
= UNIMPLEMENTED
,
165 .TIMER
= UNIMPLEMENTED
,
166 .BOOTSTS
= UNIMPLEMENTED
,
167 .CTL_1
= UNIMPLEMENTED
,
169 static const struct config_registers v5_config_registers
= {
181 .FLR
= UNIMPLEMENTED
,
182 .KEY
= UNIMPLEMENTED
,
195 * hwicap_command_desync - Send a DESYNC command to the ICAP port.
196 * @drvdata: a pointer to the drvdata.
198 * This command desynchronizes the ICAP After this command, a
199 * bitstream containing a NULL packet, followed by a SYNCH packet is
200 * required before the ICAP will recognize commands.
202 static int hwicap_command_desync(struct hwicap_drvdata
*drvdata
)
208 * Create the data to be written to the ICAP.
210 buffer
[index
++] = hwicap_type_1_write(drvdata
->config_regs
->CMD
) | 1;
211 buffer
[index
++] = XHI_CMD_DESYNCH
;
212 buffer
[index
++] = XHI_NOOP_PACKET
;
213 buffer
[index
++] = XHI_NOOP_PACKET
;
216 * Write the data to the FIFO and intiate the transfer of data present
217 * in the FIFO to the ICAP device.
219 return drvdata
->config
->set_configuration(drvdata
,
224 * hwicap_get_configuration_register - Query a configuration register.
225 * @drvdata: a pointer to the drvdata.
226 * @reg: a constant which represents the configuration
227 * register value to be returned.
228 * Examples: XHI_IDCODE, XHI_FLR.
229 * @reg_data: returns the value of the register.
231 * Sends a query packet to the ICAP and then receives the response.
232 * The icap is left in Synched state.
234 static int hwicap_get_configuration_register(struct hwicap_drvdata
*drvdata
,
235 u32 reg
, u32
*reg_data
)
242 * Create the data to be written to the ICAP.
244 buffer
[index
++] = XHI_DUMMY_PACKET
;
245 buffer
[index
++] = XHI_NOOP_PACKET
;
246 buffer
[index
++] = XHI_SYNC_PACKET
;
247 buffer
[index
++] = XHI_NOOP_PACKET
;
248 buffer
[index
++] = XHI_NOOP_PACKET
;
251 * Write the data to the FIFO and initiate the transfer of data present
252 * in the FIFO to the ICAP device.
254 status
= drvdata
->config
->set_configuration(drvdata
,
259 /* If the syncword was not found, then we need to start over. */
260 status
= drvdata
->config
->get_status(drvdata
);
261 if ((status
& XHI_SR_DALIGN_MASK
) != XHI_SR_DALIGN_MASK
)
265 buffer
[index
++] = hwicap_type_1_read(reg
) | 1;
266 buffer
[index
++] = XHI_NOOP_PACKET
;
267 buffer
[index
++] = XHI_NOOP_PACKET
;
270 * Write the data to the FIFO and intiate the transfer of data present
271 * in the FIFO to the ICAP device.
273 status
= drvdata
->config
->set_configuration(drvdata
,
279 * Read the configuration register
281 status
= drvdata
->config
->get_configuration(drvdata
, reg_data
, 1);
288 static int hwicap_initialize_hwicap(struct hwicap_drvdata
*drvdata
)
293 dev_dbg(drvdata
->dev
, "initializing\n");
295 /* Abort any current transaction, to make sure we have the
296 * ICAP in a good state. */
297 dev_dbg(drvdata
->dev
, "Reset...\n");
298 drvdata
->config
->reset(drvdata
);
300 dev_dbg(drvdata
->dev
, "Desync...\n");
301 status
= hwicap_command_desync(drvdata
);
305 /* Attempt to read the IDCODE from ICAP. This
306 * may not be returned correctly, due to the design of the
309 dev_dbg(drvdata
->dev
, "Reading IDCODE...\n");
310 status
= hwicap_get_configuration_register(
311 drvdata
, drvdata
->config_regs
->IDCODE
, &idcode
);
312 dev_dbg(drvdata
->dev
, "IDCODE = %x\n", idcode
);
316 dev_dbg(drvdata
->dev
, "Desync...\n");
317 status
= hwicap_command_desync(drvdata
);
325 hwicap_read(struct file
*file
, char __user
*buf
, size_t count
, loff_t
*ppos
)
327 struct hwicap_drvdata
*drvdata
= file
->private_data
;
328 ssize_t bytes_to_read
= 0;
334 status
= mutex_lock_interruptible(&drvdata
->sem
);
338 if (drvdata
->read_buffer_in_use
) {
339 /* If there are leftover bytes in the buffer, just */
340 /* return them and don't try to read more from the */
343 (count
< drvdata
->read_buffer_in_use
) ? count
:
344 drvdata
->read_buffer_in_use
;
346 /* Return the data currently in the read buffer. */
347 if (copy_to_user(buf
, drvdata
->read_buffer
, bytes_to_read
)) {
351 drvdata
->read_buffer_in_use
-= bytes_to_read
;
352 memmove(drvdata
->read_buffer
,
353 drvdata
->read_buffer
+ bytes_to_read
,
356 /* Get new data from the ICAP, and return was was requested. */
357 kbuf
= (u32
*) get_zeroed_page(GFP_KERNEL
);
363 /* The ICAP device is only able to read complete */
364 /* words. If a number of bytes that do not correspond */
365 /* to complete words is requested, then we read enough */
366 /* words to get the required number of bytes, and then */
367 /* save the remaining bytes for the next read. */
369 /* Determine the number of words to read, rounding up */
371 words
= ((count
+ 3) >> 2);
372 bytes_to_read
= words
<< 2;
374 if (bytes_to_read
> PAGE_SIZE
)
375 bytes_to_read
= PAGE_SIZE
;
377 /* Ensure we only read a complete number of words. */
378 bytes_remaining
= bytes_to_read
& 3;
380 words
= bytes_to_read
>> 2;
382 status
= drvdata
->config
->get_configuration(drvdata
,
385 /* If we didn't read correctly, then bail out. */
387 free_page((unsigned long)kbuf
);
391 /* If we fail to return the data to the user, then bail out. */
392 if (copy_to_user(buf
, kbuf
, bytes_to_read
)) {
393 free_page((unsigned long)kbuf
);
397 memcpy(drvdata
->read_buffer
,
400 drvdata
->read_buffer_in_use
= bytes_remaining
;
401 free_page((unsigned long)kbuf
);
403 status
= bytes_to_read
;
405 mutex_unlock(&drvdata
->sem
);
410 hwicap_write(struct file
*file
, const char __user
*buf
,
411 size_t count
, loff_t
*ppos
)
413 struct hwicap_drvdata
*drvdata
= file
->private_data
;
415 ssize_t left
= count
;
420 status
= mutex_lock_interruptible(&drvdata
->sem
);
424 left
+= drvdata
->write_buffer_in_use
;
426 /* Only write multiples of 4 bytes. */
432 kbuf
= (u32
*) __get_free_page(GFP_KERNEL
);
439 /* only write multiples of 4 bytes, so there might */
440 /* be as many as 3 bytes left (at the end). */
447 if (drvdata
->write_buffer_in_use
) {
448 memcpy(kbuf
, drvdata
->write_buffer
,
449 drvdata
->write_buffer_in_use
);
451 (((char *)kbuf
) + drvdata
->write_buffer_in_use
),
453 len
- (drvdata
->write_buffer_in_use
))) {
454 free_page((unsigned long)kbuf
);
459 if (copy_from_user(kbuf
, buf
+ written
, len
)) {
460 free_page((unsigned long)kbuf
);
466 status
= drvdata
->config
->set_configuration(drvdata
,
470 free_page((unsigned long)kbuf
);
474 if (drvdata
->write_buffer_in_use
) {
475 len
-= drvdata
->write_buffer_in_use
;
476 left
-= drvdata
->write_buffer_in_use
;
477 drvdata
->write_buffer_in_use
= 0;
482 if ((left
> 0) && (left
< 4)) {
483 if (!copy_from_user(drvdata
->write_buffer
,
484 buf
+ written
, left
)) {
485 drvdata
->write_buffer_in_use
= left
;
491 free_page((unsigned long)kbuf
);
494 mutex_unlock(&drvdata
->sem
);
498 static int hwicap_open(struct inode
*inode
, struct file
*file
)
500 struct hwicap_drvdata
*drvdata
;
504 drvdata
= container_of(inode
->i_cdev
, struct hwicap_drvdata
, cdev
);
506 status
= mutex_lock_interruptible(&drvdata
->sem
);
510 if (drvdata
->is_open
) {
515 status
= hwicap_initialize_hwicap(drvdata
);
517 dev_err(drvdata
->dev
, "Failed to open file");
521 file
->private_data
= drvdata
;
522 drvdata
->write_buffer_in_use
= 0;
523 drvdata
->read_buffer_in_use
= 0;
524 drvdata
->is_open
= 1;
527 mutex_unlock(&drvdata
->sem
);
533 static int hwicap_release(struct inode
*inode
, struct file
*file
)
535 struct hwicap_drvdata
*drvdata
= file
->private_data
;
539 mutex_lock(&drvdata
->sem
);
541 if (drvdata
->write_buffer_in_use
) {
542 /* Flush write buffer. */
543 for (i
= drvdata
->write_buffer_in_use
; i
< 4; i
++)
544 drvdata
->write_buffer
[i
] = 0;
546 status
= drvdata
->config
->set_configuration(drvdata
,
547 (u32
*) drvdata
->write_buffer
, 1);
552 status
= hwicap_command_desync(drvdata
);
557 drvdata
->is_open
= 0;
558 mutex_unlock(&drvdata
->sem
);
562 static struct file_operations hwicap_fops
= {
563 .owner
= THIS_MODULE
,
564 .write
= hwicap_write
,
567 .release
= hwicap_release
,
570 static int __devinit
hwicap_setup(struct device
*dev
, int id
,
571 const struct resource
*regs_res
,
572 const struct hwicap_driver_config
*config
,
573 const struct config_registers
*config_regs
)
576 struct hwicap_drvdata
*drvdata
= NULL
;
579 dev_info(dev
, "Xilinx icap port driver\n");
581 mutex_lock(&icap_sem
);
584 for (id
= 0; id
< HWICAP_DEVICES
; id
++)
585 if (!probed_devices
[id
])
588 if (id
< 0 || id
>= HWICAP_DEVICES
) {
589 mutex_unlock(&icap_sem
);
590 dev_err(dev
, "%s%i too large\n", DRIVER_NAME
, id
);
593 if (probed_devices
[id
]) {
594 mutex_unlock(&icap_sem
);
595 dev_err(dev
, "cannot assign to %s%i; it is already in use\n",
600 probed_devices
[id
] = 1;
601 mutex_unlock(&icap_sem
);
603 devt
= MKDEV(XHWICAP_MAJOR
, XHWICAP_MINOR
+ id
);
605 drvdata
= kzalloc(sizeof(struct hwicap_drvdata
), GFP_KERNEL
);
607 dev_err(dev
, "Couldn't allocate device private record\n");
611 dev_set_drvdata(dev
, (void *)drvdata
);
614 dev_err(dev
, "Couldn't get registers resource\n");
619 drvdata
->mem_start
= regs_res
->start
;
620 drvdata
->mem_end
= regs_res
->end
;
621 drvdata
->mem_size
= regs_res
->end
- regs_res
->start
+ 1;
623 if (!request_mem_region(drvdata
->mem_start
,
624 drvdata
->mem_size
, DRIVER_NAME
)) {
625 dev_err(dev
, "Couldn't lock memory region at %Lx\n",
626 (unsigned long long) regs_res
->start
);
631 drvdata
->devt
= devt
;
633 drvdata
->base_address
= ioremap(drvdata
->mem_start
, drvdata
->mem_size
);
634 if (!drvdata
->base_address
) {
635 dev_err(dev
, "ioremap() failed\n");
639 drvdata
->config
= config
;
640 drvdata
->config_regs
= config_regs
;
642 mutex_init(&drvdata
->sem
);
643 drvdata
->is_open
= 0;
645 dev_info(dev
, "ioremap %llx to %p with size %llx\n",
646 (unsigned long long) drvdata
->mem_start
,
647 drvdata
->base_address
,
648 (unsigned long long) 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");
658 device_create(icap_class
, dev
, devt
, NULL
, "%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 __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
},
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");