2 * This file is provided under a dual BSD/GPLv2 license. When using or
3 * redistributing this file, you may do so under either license.
7 * Copyright(c) 2012 Intel Corporation. All rights reserved.
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of version 2 of the GNU General Public License as
11 * published by the Free Software Foundation.
15 * Copyright(c) 2012 Intel Corporation. All rights reserved.
17 * Redistribution and use in source and binary forms, with or without
18 * modification, are permitted provided that the following conditions
21 * * Redistributions of source code must retain the above copyright
22 * notice, this list of conditions and the following disclaimer.
23 * * Redistributions in binary form must reproduce the above copy
24 * notice, this list of conditions and the following disclaimer in
25 * the documentation and/or other materials provided with the
27 * * Neither the name of Intel Corporation nor the names of its
28 * contributors may be used to endorse or promote products derived
29 * from this software without specific prior written permission.
31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
36 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
37 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
38 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
39 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
40 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
41 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
43 * Intel PCIe NTB Linux driver
45 * Contact Information:
46 * Jon Mason <jon.mason@intel.com>
48 #include <linux/debugfs.h>
49 #include <linux/delay.h>
50 #include <linux/dmaengine.h>
51 #include <linux/dma-mapping.h>
52 #include <linux/errno.h>
53 #include <linux/export.h>
54 #include <linux/interrupt.h>
55 #include <linux/module.h>
56 #include <linux/pci.h>
57 #include <linux/slab.h>
58 #include <linux/types.h>
59 #include <linux/ntb.h>
62 #define NTB_TRANSPORT_VERSION 3
64 static unsigned int transport_mtu
= 0x401E;
65 module_param(transport_mtu
, uint
, 0644);
66 MODULE_PARM_DESC(transport_mtu
, "Maximum size of NTB transport packets");
68 static unsigned char max_num_clients
;
69 module_param(max_num_clients
, byte
, 0644);
70 MODULE_PARM_DESC(max_num_clients
, "Maximum number of NTB transport clients");
72 static unsigned int copy_bytes
= 1024;
73 module_param(copy_bytes
, uint
, 0644);
74 MODULE_PARM_DESC(copy_bytes
, "Threshold under which NTB will use the CPU to copy instead of DMA");
76 struct ntb_queue_entry
{
77 /* ntb_queue list reference */
78 struct list_head entry
;
79 /* pointers to data to be transfered */
85 struct ntb_transport_qp
*qp
;
87 struct ntb_payload_header __iomem
*tx_hdr
;
88 struct ntb_payload_header
*rx_hdr
;
97 struct ntb_transport_qp
{
98 struct ntb_transport
*transport
;
99 struct ntb_device
*ndev
;
101 struct dma_chan
*dma_chan
;
105 u8 qp_num
; /* Only 64 QP's are allowed. 0-63 */
107 struct ntb_rx_info __iomem
*rx_info
;
108 struct ntb_rx_info
*remote_rx_info
;
110 void (*tx_handler
) (struct ntb_transport_qp
*qp
, void *qp_data
,
111 void *data
, int len
);
112 struct list_head tx_free_q
;
113 spinlock_t ntb_tx_free_q_lock
;
115 dma_addr_t tx_mw_phys
;
116 unsigned int tx_index
;
117 unsigned int tx_max_entry
;
118 unsigned int tx_max_frame
;
120 void (*rx_handler
) (struct ntb_transport_qp
*qp
, void *qp_data
,
121 void *data
, int len
);
122 struct list_head rx_pend_q
;
123 struct list_head rx_free_q
;
124 spinlock_t ntb_rx_pend_q_lock
;
125 spinlock_t ntb_rx_free_q_lock
;
127 unsigned int rx_index
;
128 unsigned int rx_max_entry
;
129 unsigned int rx_max_frame
;
130 dma_cookie_t last_cookie
;
132 void (*event_handler
) (void *data
, int status
);
133 struct delayed_work link_work
;
134 struct work_struct link_cleanup
;
136 struct dentry
*debugfs_dir
;
137 struct dentry
*debugfs_stats
;
156 struct ntb_transport_mw
{
162 struct ntb_transport_client_dev
{
163 struct list_head entry
;
167 struct ntb_transport
{
168 struct list_head entry
;
169 struct list_head client_devs
;
171 struct ntb_device
*ndev
;
172 struct ntb_transport_mw
*mw
;
173 struct ntb_transport_qp
*qps
;
174 unsigned int max_qps
;
175 unsigned long qp_bitmap
;
177 struct delayed_work link_work
;
178 struct work_struct link_cleanup
;
182 DESC_DONE_FLAG
= 1 << 0,
183 LINK_DOWN_FLAG
= 1 << 1,
186 struct ntb_payload_header
{
204 #define QP_TO_MW(ndev, qp) ((qp) % ntb_max_mw(ndev))
205 #define NTB_QP_DEF_NUM_ENTRIES 100
206 #define NTB_LINK_DOWN_TIMEOUT 10
208 static int ntb_match_bus(struct device
*dev
, struct device_driver
*drv
)
210 return !strncmp(dev_name(dev
), drv
->name
, strlen(drv
->name
));
213 static int ntb_client_probe(struct device
*dev
)
215 const struct ntb_client
*drv
= container_of(dev
->driver
,
216 struct ntb_client
, driver
);
217 struct pci_dev
*pdev
= container_of(dev
->parent
, struct pci_dev
, dev
);
221 if (drv
&& drv
->probe
)
222 rc
= drv
->probe(pdev
);
229 static int ntb_client_remove(struct device
*dev
)
231 const struct ntb_client
*drv
= container_of(dev
->driver
,
232 struct ntb_client
, driver
);
233 struct pci_dev
*pdev
= container_of(dev
->parent
, struct pci_dev
, dev
);
235 if (drv
&& drv
->remove
)
243 static struct bus_type ntb_bus_type
= {
245 .match
= ntb_match_bus
,
246 .probe
= ntb_client_probe
,
247 .remove
= ntb_client_remove
,
250 static LIST_HEAD(ntb_transport_list
);
252 static int ntb_bus_init(struct ntb_transport
*nt
)
254 if (list_empty(&ntb_transport_list
)) {
255 int rc
= bus_register(&ntb_bus_type
);
260 list_add(&nt
->entry
, &ntb_transport_list
);
265 static void ntb_bus_remove(struct ntb_transport
*nt
)
267 struct ntb_transport_client_dev
*client_dev
, *cd
;
269 list_for_each_entry_safe(client_dev
, cd
, &nt
->client_devs
, entry
) {
270 dev_err(client_dev
->dev
.parent
, "%s still attached to bus, removing\n",
271 dev_name(&client_dev
->dev
));
272 list_del(&client_dev
->entry
);
273 device_unregister(&client_dev
->dev
);
276 list_del(&nt
->entry
);
278 if (list_empty(&ntb_transport_list
))
279 bus_unregister(&ntb_bus_type
);
282 static void ntb_client_release(struct device
*dev
)
284 struct ntb_transport_client_dev
*client_dev
;
285 client_dev
= container_of(dev
, struct ntb_transport_client_dev
, dev
);
291 * ntb_unregister_client_dev - Unregister NTB client device
292 * @device_name: Name of NTB client device
294 * Unregister an NTB client device with the NTB transport layer
296 void ntb_unregister_client_dev(char *device_name
)
298 struct ntb_transport_client_dev
*client
, *cd
;
299 struct ntb_transport
*nt
;
301 list_for_each_entry(nt
, &ntb_transport_list
, entry
)
302 list_for_each_entry_safe(client
, cd
, &nt
->client_devs
, entry
)
303 if (!strncmp(dev_name(&client
->dev
), device_name
,
304 strlen(device_name
))) {
305 list_del(&client
->entry
);
306 device_unregister(&client
->dev
);
309 EXPORT_SYMBOL_GPL(ntb_unregister_client_dev
);
312 * ntb_register_client_dev - Register NTB client device
313 * @device_name: Name of NTB client device
315 * Register an NTB client device with the NTB transport layer
317 int ntb_register_client_dev(char *device_name
)
319 struct ntb_transport_client_dev
*client_dev
;
320 struct ntb_transport
*nt
;
323 if (list_empty(&ntb_transport_list
))
326 list_for_each_entry(nt
, &ntb_transport_list
, entry
) {
329 client_dev
= kzalloc(sizeof(struct ntb_transport_client_dev
),
336 dev
= &client_dev
->dev
;
338 /* setup and register client devices */
339 dev_set_name(dev
, "%s%d", device_name
, i
);
340 dev
->bus
= &ntb_bus_type
;
341 dev
->release
= ntb_client_release
;
342 dev
->parent
= &ntb_query_pdev(nt
->ndev
)->dev
;
344 rc
= device_register(dev
);
350 list_add_tail(&client_dev
->entry
, &nt
->client_devs
);
357 ntb_unregister_client_dev(device_name
);
361 EXPORT_SYMBOL_GPL(ntb_register_client_dev
);
364 * ntb_register_client - Register NTB client driver
365 * @drv: NTB client driver to be registered
367 * Register an NTB client driver with the NTB transport layer
369 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
371 int ntb_register_client(struct ntb_client
*drv
)
373 drv
->driver
.bus
= &ntb_bus_type
;
375 if (list_empty(&ntb_transport_list
))
378 return driver_register(&drv
->driver
);
380 EXPORT_SYMBOL_GPL(ntb_register_client
);
383 * ntb_unregister_client - Unregister NTB client driver
384 * @drv: NTB client driver to be unregistered
386 * Unregister an NTB client driver with the NTB transport layer
388 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
390 void ntb_unregister_client(struct ntb_client
*drv
)
392 driver_unregister(&drv
->driver
);
394 EXPORT_SYMBOL_GPL(ntb_unregister_client
);
396 static ssize_t
debugfs_read(struct file
*filp
, char __user
*ubuf
, size_t count
,
399 struct ntb_transport_qp
*qp
;
401 ssize_t ret
, out_offset
, out_count
;
405 buf
= kmalloc(out_count
, GFP_KERNEL
);
409 qp
= filp
->private_data
;
411 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
413 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
414 "rx_bytes - \t%llu\n", qp
->rx_bytes
);
415 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
416 "rx_pkts - \t%llu\n", qp
->rx_pkts
);
417 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
418 "rx_memcpy - \t%llu\n", qp
->rx_memcpy
);
419 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
420 "rx_async - \t%llu\n", qp
->rx_async
);
421 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
422 "rx_ring_empty - %llu\n", qp
->rx_ring_empty
);
423 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
424 "rx_err_no_buf - %llu\n", qp
->rx_err_no_buf
);
425 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
426 "rx_err_oflow - \t%llu\n", qp
->rx_err_oflow
);
427 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
428 "rx_err_ver - \t%llu\n", qp
->rx_err_ver
);
429 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
430 "rx_buff - \t%p\n", qp
->rx_buff
);
431 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
432 "rx_index - \t%u\n", qp
->rx_index
);
433 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
434 "rx_max_entry - \t%u\n", qp
->rx_max_entry
);
436 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
437 "tx_bytes - \t%llu\n", qp
->tx_bytes
);
438 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
439 "tx_pkts - \t%llu\n", qp
->tx_pkts
);
440 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
441 "tx_memcpy - \t%llu\n", qp
->tx_memcpy
);
442 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
443 "tx_async - \t%llu\n", qp
->tx_async
);
444 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
445 "tx_ring_full - \t%llu\n", qp
->tx_ring_full
);
446 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
447 "tx_err_no_buf - %llu\n", qp
->tx_err_no_buf
);
448 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
449 "tx_mw - \t%p\n", qp
->tx_mw
);
450 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
451 "tx_index - \t%u\n", qp
->tx_index
);
452 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
453 "tx_max_entry - \t%u\n", qp
->tx_max_entry
);
455 out_offset
+= snprintf(buf
+ out_offset
, out_count
- out_offset
,
456 "\nQP Link %s\n", (qp
->qp_link
== NTB_LINK_UP
) ?
458 if (out_offset
> out_count
)
459 out_offset
= out_count
;
461 ret
= simple_read_from_buffer(ubuf
, count
, offp
, buf
, out_offset
);
466 static const struct file_operations ntb_qp_debugfs_stats
= {
467 .owner
= THIS_MODULE
,
469 .read
= debugfs_read
,
472 static void ntb_list_add(spinlock_t
*lock
, struct list_head
*entry
,
473 struct list_head
*list
)
477 spin_lock_irqsave(lock
, flags
);
478 list_add_tail(entry
, list
);
479 spin_unlock_irqrestore(lock
, flags
);
482 static struct ntb_queue_entry
*ntb_list_rm(spinlock_t
*lock
,
483 struct list_head
*list
)
485 struct ntb_queue_entry
*entry
;
488 spin_lock_irqsave(lock
, flags
);
489 if (list_empty(list
)) {
493 entry
= list_first_entry(list
, struct ntb_queue_entry
, entry
);
494 list_del(&entry
->entry
);
496 spin_unlock_irqrestore(lock
, flags
);
501 static void ntb_transport_setup_qp_mw(struct ntb_transport
*nt
,
504 struct ntb_transport_qp
*qp
= &nt
->qps
[qp_num
];
505 unsigned int rx_size
, num_qps_mw
;
509 mw_max
= ntb_max_mw(nt
->ndev
);
510 mw_num
= QP_TO_MW(nt
->ndev
, qp_num
);
512 WARN_ON(nt
->mw
[mw_num
].virt_addr
== NULL
);
514 if (nt
->max_qps
% mw_max
&& mw_num
< nt
->max_qps
% mw_max
)
515 num_qps_mw
= nt
->max_qps
/ mw_max
+ 1;
517 num_qps_mw
= nt
->max_qps
/ mw_max
;
519 rx_size
= (unsigned int) nt
->mw
[mw_num
].size
/ num_qps_mw
;
520 qp
->rx_buff
= nt
->mw
[mw_num
].virt_addr
+ qp_num
/ mw_max
* rx_size
;
521 rx_size
-= sizeof(struct ntb_rx_info
);
523 qp
->remote_rx_info
= qp
->rx_buff
+ rx_size
;
525 /* Due to housekeeping, there must be atleast 2 buffs */
526 qp
->rx_max_frame
= min(transport_mtu
, rx_size
/ 2);
527 qp
->rx_max_entry
= rx_size
/ qp
->rx_max_frame
;
530 qp
->remote_rx_info
->entry
= qp
->rx_max_entry
- 1;
532 /* setup the hdr offsets with 0's */
533 for (i
= 0; i
< qp
->rx_max_entry
; i
++) {
534 void *offset
= qp
->rx_buff
+ qp
->rx_max_frame
* (i
+ 1) -
535 sizeof(struct ntb_payload_header
);
536 memset(offset
, 0, sizeof(struct ntb_payload_header
));
544 static void ntb_free_mw(struct ntb_transport
*nt
, int num_mw
)
546 struct ntb_transport_mw
*mw
= &nt
->mw
[num_mw
];
547 struct pci_dev
*pdev
= ntb_query_pdev(nt
->ndev
);
552 dma_free_coherent(&pdev
->dev
, mw
->size
, mw
->virt_addr
, mw
->dma_addr
);
553 mw
->virt_addr
= NULL
;
556 static int ntb_set_mw(struct ntb_transport
*nt
, int num_mw
, unsigned int size
)
558 struct ntb_transport_mw
*mw
= &nt
->mw
[num_mw
];
559 struct pci_dev
*pdev
= ntb_query_pdev(nt
->ndev
);
561 /* No need to re-setup */
562 if (mw
->size
== ALIGN(size
, 4096))
566 ntb_free_mw(nt
, num_mw
);
568 /* Alloc memory for receiving data. Must be 4k aligned */
569 mw
->size
= ALIGN(size
, 4096);
571 mw
->virt_addr
= dma_alloc_coherent(&pdev
->dev
, mw
->size
, &mw
->dma_addr
,
573 if (!mw
->virt_addr
) {
575 dev_err(&pdev
->dev
, "Unable to allocate MW buffer of size %d\n",
580 /* Notify HW the memory location of the receive buffer */
581 ntb_set_mw_addr(nt
->ndev
, num_mw
, mw
->dma_addr
);
586 static void ntb_qp_link_cleanup(struct ntb_transport_qp
*qp
)
588 struct ntb_transport
*nt
= qp
->transport
;
589 struct pci_dev
*pdev
= ntb_query_pdev(nt
->ndev
);
591 if (qp
->qp_link
== NTB_LINK_DOWN
) {
592 cancel_delayed_work_sync(&qp
->link_work
);
596 if (qp
->event_handler
)
597 qp
->event_handler(qp
->cb_data
, NTB_LINK_DOWN
);
599 dev_info(&pdev
->dev
, "qp %d: Link Down\n", qp
->qp_num
);
600 qp
->qp_link
= NTB_LINK_DOWN
;
603 static void ntb_qp_link_cleanup_work(struct work_struct
*work
)
605 struct ntb_transport_qp
*qp
= container_of(work
,
606 struct ntb_transport_qp
,
608 struct ntb_transport
*nt
= qp
->transport
;
610 ntb_qp_link_cleanup(qp
);
612 if (nt
->transport_link
== NTB_LINK_UP
)
613 schedule_delayed_work(&qp
->link_work
,
614 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT
));
617 static void ntb_qp_link_down(struct ntb_transport_qp
*qp
)
619 schedule_work(&qp
->link_cleanup
);
622 static void ntb_transport_link_cleanup(struct ntb_transport
*nt
)
626 /* Pass along the info to any clients */
627 for (i
= 0; i
< nt
->max_qps
; i
++)
628 if (!test_bit(i
, &nt
->qp_bitmap
))
629 ntb_qp_link_cleanup(&nt
->qps
[i
]);
631 if (nt
->transport_link
== NTB_LINK_DOWN
)
632 cancel_delayed_work_sync(&nt
->link_work
);
634 nt
->transport_link
= NTB_LINK_DOWN
;
636 /* The scratchpad registers keep the values if the remote side
637 * goes down, blast them now to give them a sane value the next
638 * time they are accessed
640 for (i
= 0; i
< MAX_SPAD
; i
++)
641 ntb_write_local_spad(nt
->ndev
, i
, 0);
644 static void ntb_transport_link_cleanup_work(struct work_struct
*work
)
646 struct ntb_transport
*nt
= container_of(work
, struct ntb_transport
,
649 ntb_transport_link_cleanup(nt
);
652 static void ntb_transport_event_callback(void *data
, enum ntb_hw_event event
)
654 struct ntb_transport
*nt
= data
;
657 case NTB_EVENT_HW_LINK_UP
:
658 schedule_delayed_work(&nt
->link_work
, 0);
660 case NTB_EVENT_HW_LINK_DOWN
:
661 schedule_work(&nt
->link_cleanup
);
668 static void ntb_transport_link_work(struct work_struct
*work
)
670 struct ntb_transport
*nt
= container_of(work
, struct ntb_transport
,
672 struct ntb_device
*ndev
= nt
->ndev
;
673 struct pci_dev
*pdev
= ntb_query_pdev(ndev
);
677 /* send the local info, in the opposite order of the way we read it */
678 for (i
= 0; i
< ntb_max_mw(ndev
); i
++) {
679 rc
= ntb_write_remote_spad(ndev
, MW0_SZ_HIGH
+ (i
* 2),
680 ntb_get_mw_size(ndev
, i
) >> 32);
682 dev_err(&pdev
->dev
, "Error writing %u to remote spad %d\n",
683 (u32
)(ntb_get_mw_size(ndev
, i
) >> 32),
684 MW0_SZ_HIGH
+ (i
* 2));
688 rc
= ntb_write_remote_spad(ndev
, MW0_SZ_LOW
+ (i
* 2),
689 (u32
) ntb_get_mw_size(ndev
, i
));
691 dev_err(&pdev
->dev
, "Error writing %u to remote spad %d\n",
692 (u32
) ntb_get_mw_size(ndev
, i
),
693 MW0_SZ_LOW
+ (i
* 2));
698 rc
= ntb_write_remote_spad(ndev
, NUM_MWS
, ntb_max_mw(ndev
));
700 dev_err(&pdev
->dev
, "Error writing %x to remote spad %d\n",
701 ntb_max_mw(ndev
), NUM_MWS
);
705 rc
= ntb_write_remote_spad(ndev
, NUM_QPS
, nt
->max_qps
);
707 dev_err(&pdev
->dev
, "Error writing %x to remote spad %d\n",
708 nt
->max_qps
, NUM_QPS
);
712 rc
= ntb_write_remote_spad(ndev
, VERSION
, NTB_TRANSPORT_VERSION
);
714 dev_err(&pdev
->dev
, "Error writing %x to remote spad %d\n",
715 NTB_TRANSPORT_VERSION
, VERSION
);
719 /* Query the remote side for its info */
720 rc
= ntb_read_remote_spad(ndev
, VERSION
, &val
);
722 dev_err(&pdev
->dev
, "Error reading remote spad %d\n", VERSION
);
726 if (val
!= NTB_TRANSPORT_VERSION
)
728 dev_dbg(&pdev
->dev
, "Remote version = %d\n", val
);
730 rc
= ntb_read_remote_spad(ndev
, NUM_QPS
, &val
);
732 dev_err(&pdev
->dev
, "Error reading remote spad %d\n", NUM_QPS
);
736 if (val
!= nt
->max_qps
)
738 dev_dbg(&pdev
->dev
, "Remote max number of qps = %d\n", val
);
740 rc
= ntb_read_remote_spad(ndev
, NUM_MWS
, &val
);
742 dev_err(&pdev
->dev
, "Error reading remote spad %d\n", NUM_MWS
);
746 if (val
!= ntb_max_mw(ndev
))
748 dev_dbg(&pdev
->dev
, "Remote number of mws = %d\n", val
);
750 for (i
= 0; i
< ntb_max_mw(ndev
); i
++) {
753 rc
= ntb_read_remote_spad(ndev
, MW0_SZ_HIGH
+ (i
* 2), &val
);
755 dev_err(&pdev
->dev
, "Error reading remote spad %d\n",
756 MW0_SZ_HIGH
+ (i
* 2));
760 val64
= (u64
) val
<< 32;
762 rc
= ntb_read_remote_spad(ndev
, MW0_SZ_LOW
+ (i
* 2), &val
);
764 dev_err(&pdev
->dev
, "Error reading remote spad %d\n",
765 MW0_SZ_LOW
+ (i
* 2));
771 dev_dbg(&pdev
->dev
, "Remote MW%d size = %llu\n", i
, val64
);
773 rc
= ntb_set_mw(nt
, i
, val64
);
778 nt
->transport_link
= NTB_LINK_UP
;
780 for (i
= 0; i
< nt
->max_qps
; i
++) {
781 struct ntb_transport_qp
*qp
= &nt
->qps
[i
];
783 ntb_transport_setup_qp_mw(nt
, i
);
785 if (qp
->client_ready
== NTB_LINK_UP
)
786 schedule_delayed_work(&qp
->link_work
, 0);
792 for (i
= 0; i
< ntb_max_mw(ndev
); i
++)
795 if (ntb_hw_link_status(ndev
))
796 schedule_delayed_work(&nt
->link_work
,
797 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT
));
800 static void ntb_qp_link_work(struct work_struct
*work
)
802 struct ntb_transport_qp
*qp
= container_of(work
,
803 struct ntb_transport_qp
,
805 struct pci_dev
*pdev
= ntb_query_pdev(qp
->ndev
);
806 struct ntb_transport
*nt
= qp
->transport
;
809 WARN_ON(nt
->transport_link
!= NTB_LINK_UP
);
811 rc
= ntb_read_local_spad(nt
->ndev
, QP_LINKS
, &val
);
813 dev_err(&pdev
->dev
, "Error reading spad %d\n", QP_LINKS
);
817 rc
= ntb_write_remote_spad(nt
->ndev
, QP_LINKS
, val
| 1 << qp
->qp_num
);
819 dev_err(&pdev
->dev
, "Error writing %x to remote spad %d\n",
820 val
| 1 << qp
->qp_num
, QP_LINKS
);
822 /* query remote spad for qp ready bits */
823 rc
= ntb_read_remote_spad(nt
->ndev
, QP_LINKS
, &val
);
825 dev_err(&pdev
->dev
, "Error reading remote spad %d\n", QP_LINKS
);
827 dev_dbg(&pdev
->dev
, "Remote QP link status = %x\n", val
);
829 /* See if the remote side is up */
830 if (1 << qp
->qp_num
& val
) {
831 qp
->qp_link
= NTB_LINK_UP
;
833 dev_info(&pdev
->dev
, "qp %d: Link Up\n", qp
->qp_num
);
834 if (qp
->event_handler
)
835 qp
->event_handler(qp
->cb_data
, NTB_LINK_UP
);
836 } else if (nt
->transport_link
== NTB_LINK_UP
)
837 schedule_delayed_work(&qp
->link_work
,
838 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT
));
841 static int ntb_transport_init_queue(struct ntb_transport
*nt
,
844 struct ntb_transport_qp
*qp
;
845 unsigned int num_qps_mw
, tx_size
;
849 mw_max
= ntb_max_mw(nt
->ndev
);
850 mw_num
= QP_TO_MW(nt
->ndev
, qp_num
);
852 qp
= &nt
->qps
[qp_num
];
856 qp
->qp_link
= NTB_LINK_DOWN
;
857 qp
->client_ready
= NTB_LINK_DOWN
;
858 qp
->event_handler
= NULL
;
860 if (nt
->max_qps
% mw_max
&& mw_num
< nt
->max_qps
% mw_max
)
861 num_qps_mw
= nt
->max_qps
/ mw_max
+ 1;
863 num_qps_mw
= nt
->max_qps
/ mw_max
;
865 tx_size
= (unsigned int) ntb_get_mw_size(qp
->ndev
, mw_num
) / num_qps_mw
;
866 qp_offset
= qp_num
/ mw_max
* tx_size
;
867 qp
->tx_mw
= ntb_get_mw_vbase(nt
->ndev
, mw_num
) + qp_offset
;
871 qp
->tx_mw_phys
= ntb_get_mw_base(qp
->ndev
, mw_num
) + qp_offset
;
875 tx_size
-= sizeof(struct ntb_rx_info
);
876 qp
->rx_info
= qp
->tx_mw
+ tx_size
;
878 /* Due to housekeeping, there must be atleast 2 buffs */
879 qp
->tx_max_frame
= min(transport_mtu
, tx_size
/ 2);
880 qp
->tx_max_entry
= tx_size
/ qp
->tx_max_frame
;
882 if (ntb_query_debugfs(nt
->ndev
)) {
883 char debugfs_name
[4];
885 snprintf(debugfs_name
, 4, "qp%d", qp_num
);
886 qp
->debugfs_dir
= debugfs_create_dir(debugfs_name
,
887 ntb_query_debugfs(nt
->ndev
));
889 qp
->debugfs_stats
= debugfs_create_file("stats", S_IRUSR
,
891 &ntb_qp_debugfs_stats
);
894 INIT_DELAYED_WORK(&qp
->link_work
, ntb_qp_link_work
);
895 INIT_WORK(&qp
->link_cleanup
, ntb_qp_link_cleanup_work
);
897 spin_lock_init(&qp
->ntb_rx_pend_q_lock
);
898 spin_lock_init(&qp
->ntb_rx_free_q_lock
);
899 spin_lock_init(&qp
->ntb_tx_free_q_lock
);
901 INIT_LIST_HEAD(&qp
->rx_pend_q
);
902 INIT_LIST_HEAD(&qp
->rx_free_q
);
903 INIT_LIST_HEAD(&qp
->tx_free_q
);
908 int ntb_transport_init(struct pci_dev
*pdev
)
910 struct ntb_transport
*nt
;
913 nt
= kzalloc(sizeof(struct ntb_transport
), GFP_KERNEL
);
917 nt
->ndev
= ntb_register_transport(pdev
, nt
);
923 nt
->mw
= kcalloc(ntb_max_mw(nt
->ndev
), sizeof(struct ntb_transport_mw
),
931 nt
->max_qps
= min(ntb_max_cbs(nt
->ndev
), max_num_clients
);
933 nt
->max_qps
= min(ntb_max_cbs(nt
->ndev
), ntb_max_mw(nt
->ndev
));
935 nt
->qps
= kcalloc(nt
->max_qps
, sizeof(struct ntb_transport_qp
),
942 nt
->qp_bitmap
= ((u64
) 1 << nt
->max_qps
) - 1;
944 for (i
= 0; i
< nt
->max_qps
; i
++) {
945 rc
= ntb_transport_init_queue(nt
, i
);
950 INIT_DELAYED_WORK(&nt
->link_work
, ntb_transport_link_work
);
951 INIT_WORK(&nt
->link_cleanup
, ntb_transport_link_cleanup_work
);
953 rc
= ntb_register_event_callback(nt
->ndev
,
954 ntb_transport_event_callback
);
958 INIT_LIST_HEAD(&nt
->client_devs
);
959 rc
= ntb_bus_init(nt
);
963 if (ntb_hw_link_status(nt
->ndev
))
964 schedule_delayed_work(&nt
->link_work
, 0);
969 ntb_unregister_event_callback(nt
->ndev
);
975 ntb_unregister_transport(nt
->ndev
);
981 void ntb_transport_free(void *transport
)
983 struct ntb_transport
*nt
= transport
;
984 struct ntb_device
*ndev
= nt
->ndev
;
987 ntb_transport_link_cleanup(nt
);
989 /* verify that all the qp's are freed */
990 for (i
= 0; i
< nt
->max_qps
; i
++) {
991 if (!test_bit(i
, &nt
->qp_bitmap
))
992 ntb_transport_free_queue(&nt
->qps
[i
]);
993 debugfs_remove_recursive(nt
->qps
[i
].debugfs_dir
);
998 cancel_delayed_work_sync(&nt
->link_work
);
1000 ntb_unregister_event_callback(ndev
);
1002 for (i
= 0; i
< ntb_max_mw(ndev
); i
++)
1007 ntb_unregister_transport(ndev
);
1011 static void ntb_rx_copy_callback(void *data
)
1013 struct ntb_queue_entry
*entry
= data
;
1014 struct ntb_transport_qp
*qp
= entry
->qp
;
1015 void *cb_data
= entry
->cb_data
;
1016 unsigned int len
= entry
->len
;
1017 struct ntb_payload_header
*hdr
= entry
->rx_hdr
;
1019 /* Ensure that the data is fully copied out before clearing the flag */
1023 iowrite32(entry
->index
, &qp
->rx_info
->entry
);
1025 ntb_list_add(&qp
->ntb_rx_free_q_lock
, &entry
->entry
, &qp
->rx_free_q
);
1027 if (qp
->rx_handler
&& qp
->client_ready
== NTB_LINK_UP
)
1028 qp
->rx_handler(qp
, qp
->cb_data
, cb_data
, len
);
1031 static void ntb_memcpy_rx(struct ntb_queue_entry
*entry
, void *offset
)
1033 void *buf
= entry
->buf
;
1034 size_t len
= entry
->len
;
1036 memcpy(buf
, offset
, len
);
1038 ntb_rx_copy_callback(entry
);
1041 static void ntb_async_rx(struct ntb_queue_entry
*entry
, void *offset
,
1044 struct dma_async_tx_descriptor
*txd
;
1045 struct ntb_transport_qp
*qp
= entry
->qp
;
1046 struct dma_chan
*chan
= qp
->dma_chan
;
1047 struct dma_device
*device
;
1048 size_t pay_off
, buff_off
;
1049 dma_addr_t src
, dest
;
1050 dma_cookie_t cookie
;
1051 void *buf
= entry
->buf
;
1052 unsigned long flags
;
1059 if (len
< copy_bytes
)
1062 device
= chan
->device
;
1063 pay_off
= (size_t) offset
& ~PAGE_MASK
;
1064 buff_off
= (size_t) buf
& ~PAGE_MASK
;
1066 if (!is_dma_copy_aligned(device
, pay_off
, buff_off
, len
))
1069 dest
= dma_map_single(device
->dev
, buf
, len
, DMA_FROM_DEVICE
);
1070 if (dma_mapping_error(device
->dev
, dest
))
1073 src
= dma_map_single(device
->dev
, offset
, len
, DMA_TO_DEVICE
);
1074 if (dma_mapping_error(device
->dev
, src
))
1077 flags
= DMA_COMPL_DEST_UNMAP_SINGLE
| DMA_COMPL_SRC_UNMAP_SINGLE
|
1079 txd
= device
->device_prep_dma_memcpy(chan
, dest
, src
, len
, flags
);
1083 txd
->callback
= ntb_rx_copy_callback
;
1084 txd
->callback_param
= entry
;
1086 cookie
= dmaengine_submit(txd
);
1087 if (dma_submit_error(cookie
))
1090 qp
->last_cookie
= cookie
;
1097 dma_unmap_single(device
->dev
, src
, len
, DMA_TO_DEVICE
);
1099 dma_unmap_single(device
->dev
, dest
, len
, DMA_FROM_DEVICE
);
1101 /* If the callbacks come out of order, the writing of the index to the
1102 * last completed will be out of order. This may result in the
1103 * receive stalling forever.
1105 dma_sync_wait(chan
, qp
->last_cookie
);
1107 ntb_memcpy_rx(entry
, offset
);
1111 static int ntb_process_rxc(struct ntb_transport_qp
*qp
)
1113 struct ntb_payload_header
*hdr
;
1114 struct ntb_queue_entry
*entry
;
1117 offset
= qp
->rx_buff
+ qp
->rx_max_frame
* qp
->rx_index
;
1118 hdr
= offset
+ qp
->rx_max_frame
- sizeof(struct ntb_payload_header
);
1120 entry
= ntb_list_rm(&qp
->ntb_rx_pend_q_lock
, &qp
->rx_pend_q
);
1122 dev_dbg(&ntb_query_pdev(qp
->ndev
)->dev
,
1123 "no buffer - HDR ver %u, len %d, flags %x\n",
1124 hdr
->ver
, hdr
->len
, hdr
->flags
);
1125 qp
->rx_err_no_buf
++;
1129 if (!(hdr
->flags
& DESC_DONE_FLAG
)) {
1130 ntb_list_add(&qp
->ntb_rx_pend_q_lock
, &entry
->entry
,
1132 qp
->rx_ring_empty
++;
1136 if (hdr
->ver
!= (u32
) qp
->rx_pkts
) {
1137 dev_dbg(&ntb_query_pdev(qp
->ndev
)->dev
,
1138 "qp %d: version mismatch, expected %llu - got %u\n",
1139 qp
->qp_num
, qp
->rx_pkts
, hdr
->ver
);
1140 ntb_list_add(&qp
->ntb_rx_pend_q_lock
, &entry
->entry
,
1146 if (hdr
->flags
& LINK_DOWN_FLAG
) {
1147 ntb_qp_link_down(qp
);
1152 dev_dbg(&ntb_query_pdev(qp
->ndev
)->dev
,
1153 "rx offset %u, ver %u - %d payload received, buf size %d\n",
1154 qp
->rx_index
, hdr
->ver
, hdr
->len
, entry
->len
);
1156 qp
->rx_bytes
+= hdr
->len
;
1159 if (hdr
->len
> entry
->len
) {
1161 dev_dbg(&ntb_query_pdev(qp
->ndev
)->dev
,
1162 "RX overflow! Wanted %d got %d\n",
1163 hdr
->len
, entry
->len
);
1168 entry
->index
= qp
->rx_index
;
1169 entry
->rx_hdr
= hdr
;
1171 ntb_async_rx(entry
, offset
, hdr
->len
);
1175 qp
->rx_index
%= qp
->rx_max_entry
;
1180 ntb_list_add(&qp
->ntb_rx_pend_q_lock
, &entry
->entry
,
1182 /* Ensure that the data is fully copied out before clearing the flag */
1185 iowrite32(qp
->rx_index
, &qp
->rx_info
->entry
);
1190 static int ntb_transport_rxc_db(void *data
, int db_num
)
1192 struct ntb_transport_qp
*qp
= data
;
1195 dev_dbg(&ntb_query_pdev(qp
->ndev
)->dev
, "%s: doorbell %d received\n",
1198 /* Limit the number of packets processed in a single interrupt to
1199 * provide fairness to others
1201 for (i
= 0; i
< qp
->rx_max_entry
; i
++) {
1202 rc
= ntb_process_rxc(qp
);
1208 dma_async_issue_pending(qp
->dma_chan
);
1213 static void ntb_tx_copy_callback(void *data
)
1215 struct ntb_queue_entry
*entry
= data
;
1216 struct ntb_transport_qp
*qp
= entry
->qp
;
1217 struct ntb_payload_header __iomem
*hdr
= entry
->tx_hdr
;
1219 /* Ensure that the data is fully copied out before setting the flags */
1221 iowrite32(entry
->flags
| DESC_DONE_FLAG
, &hdr
->flags
);
1223 ntb_ring_doorbell(qp
->ndev
, qp
->qp_num
);
1225 /* The entry length can only be zero if the packet is intended to be a
1226 * "link down" or similar. Since no payload is being sent in these
1227 * cases, there is nothing to add to the completion queue.
1229 if (entry
->len
> 0) {
1230 qp
->tx_bytes
+= entry
->len
;
1233 qp
->tx_handler(qp
, qp
->cb_data
, entry
->cb_data
,
1237 ntb_list_add(&qp
->ntb_tx_free_q_lock
, &entry
->entry
, &qp
->tx_free_q
);
1240 static void ntb_memcpy_tx(struct ntb_queue_entry
*entry
, void __iomem
*offset
)
1242 memcpy_toio(offset
, entry
->buf
, entry
->len
);
1244 ntb_tx_copy_callback(entry
);
1247 static void ntb_async_tx(struct ntb_transport_qp
*qp
,
1248 struct ntb_queue_entry
*entry
)
1250 struct ntb_payload_header __iomem
*hdr
;
1251 struct dma_async_tx_descriptor
*txd
;
1252 struct dma_chan
*chan
= qp
->dma_chan
;
1253 struct dma_device
*device
;
1254 size_t dest_off
, buff_off
;
1255 dma_addr_t src
, dest
;
1256 dma_cookie_t cookie
;
1257 void __iomem
*offset
;
1258 size_t len
= entry
->len
;
1259 void *buf
= entry
->buf
;
1260 unsigned long flags
;
1262 offset
= qp
->tx_mw
+ qp
->tx_max_frame
* qp
->tx_index
;
1263 hdr
= offset
+ qp
->tx_max_frame
- sizeof(struct ntb_payload_header
);
1264 entry
->tx_hdr
= hdr
;
1266 iowrite32(entry
->len
, &hdr
->len
);
1267 iowrite32((u32
) qp
->tx_pkts
, &hdr
->ver
);
1272 if (len
< copy_bytes
)
1275 device
= chan
->device
;
1276 dest
= qp
->tx_mw_phys
+ qp
->tx_max_frame
* qp
->tx_index
;
1277 buff_off
= (size_t) buf
& ~PAGE_MASK
;
1278 dest_off
= (size_t) dest
& ~PAGE_MASK
;
1280 if (!is_dma_copy_aligned(device
, buff_off
, dest_off
, len
))
1283 src
= dma_map_single(device
->dev
, buf
, len
, DMA_TO_DEVICE
);
1284 if (dma_mapping_error(device
->dev
, src
))
1287 flags
= DMA_COMPL_SRC_UNMAP_SINGLE
| DMA_PREP_INTERRUPT
;
1288 txd
= device
->device_prep_dma_memcpy(chan
, dest
, src
, len
, flags
);
1292 txd
->callback
= ntb_tx_copy_callback
;
1293 txd
->callback_param
= entry
;
1295 cookie
= dmaengine_submit(txd
);
1296 if (dma_submit_error(cookie
))
1299 dma_async_issue_pending(chan
);
1304 dma_unmap_single(device
->dev
, src
, len
, DMA_TO_DEVICE
);
1306 ntb_memcpy_tx(entry
, offset
);
1310 static int ntb_process_tx(struct ntb_transport_qp
*qp
,
1311 struct ntb_queue_entry
*entry
)
1313 dev_dbg(&ntb_query_pdev(qp
->ndev
)->dev
, "%lld - tx %u, entry len %d flags %x buff %p\n",
1314 qp
->tx_pkts
, qp
->tx_index
, entry
->len
, entry
->flags
,
1316 if (qp
->tx_index
== qp
->remote_rx_info
->entry
) {
1321 if (entry
->len
> qp
->tx_max_frame
- sizeof(struct ntb_payload_header
)) {
1323 qp
->tx_handler(qp
->cb_data
, qp
, NULL
, -EIO
);
1325 ntb_list_add(&qp
->ntb_tx_free_q_lock
, &entry
->entry
,
1330 ntb_async_tx(qp
, entry
);
1333 qp
->tx_index
%= qp
->tx_max_entry
;
1340 static void ntb_send_link_down(struct ntb_transport_qp
*qp
)
1342 struct pci_dev
*pdev
= ntb_query_pdev(qp
->ndev
);
1343 struct ntb_queue_entry
*entry
;
1346 if (qp
->qp_link
== NTB_LINK_DOWN
)
1349 qp
->qp_link
= NTB_LINK_DOWN
;
1350 dev_info(&pdev
->dev
, "qp %d: Link Down\n", qp
->qp_num
);
1352 for (i
= 0; i
< NTB_LINK_DOWN_TIMEOUT
; i
++) {
1353 entry
= ntb_list_rm(&qp
->ntb_tx_free_q_lock
, &qp
->tx_free_q
);
1362 entry
->cb_data
= NULL
;
1365 entry
->flags
= LINK_DOWN_FLAG
;
1367 rc
= ntb_process_tx(qp
, entry
);
1369 dev_err(&pdev
->dev
, "ntb: QP%d unable to send linkdown msg\n",
1374 * ntb_transport_create_queue - Create a new NTB transport layer queue
1375 * @rx_handler: receive callback function
1376 * @tx_handler: transmit callback function
1377 * @event_handler: event callback function
1379 * Create a new NTB transport layer queue and provide the queue with a callback
1380 * routine for both transmit and receive. The receive callback routine will be
1381 * used to pass up data when the transport has received it on the queue. The
1382 * transmit callback routine will be called when the transport has completed the
1383 * transmission of the data on the queue and the data is ready to be freed.
1385 * RETURNS: pointer to newly created ntb_queue, NULL on error.
1387 struct ntb_transport_qp
*
1388 ntb_transport_create_queue(void *data
, struct pci_dev
*pdev
,
1389 const struct ntb_queue_handlers
*handlers
)
1391 struct ntb_queue_entry
*entry
;
1392 struct ntb_transport_qp
*qp
;
1393 struct ntb_transport
*nt
;
1394 unsigned int free_queue
;
1397 nt
= ntb_find_transport(pdev
);
1401 free_queue
= ffs(nt
->qp_bitmap
);
1405 /* decrement free_queue to make it zero based */
1408 clear_bit(free_queue
, &nt
->qp_bitmap
);
1410 qp
= &nt
->qps
[free_queue
];
1412 qp
->rx_handler
= handlers
->rx_handler
;
1413 qp
->tx_handler
= handlers
->tx_handler
;
1414 qp
->event_handler
= handlers
->event_handler
;
1417 qp
->dma_chan
= dma_find_channel(DMA_MEMCPY
);
1418 if (!qp
->dma_chan
) {
1420 dev_info(&pdev
->dev
, "Unable to allocate DMA channel, using CPU instead\n");
1423 for (i
= 0; i
< NTB_QP_DEF_NUM_ENTRIES
; i
++) {
1424 entry
= kzalloc(sizeof(struct ntb_queue_entry
), GFP_ATOMIC
);
1429 ntb_list_add(&qp
->ntb_rx_free_q_lock
, &entry
->entry
,
1433 for (i
= 0; i
< NTB_QP_DEF_NUM_ENTRIES
; i
++) {
1434 entry
= kzalloc(sizeof(struct ntb_queue_entry
), GFP_ATOMIC
);
1439 ntb_list_add(&qp
->ntb_tx_free_q_lock
, &entry
->entry
,
1443 rc
= ntb_register_db_callback(qp
->ndev
, free_queue
, qp
,
1444 ntb_transport_rxc_db
);
1448 dev_info(&pdev
->dev
, "NTB Transport QP %d created\n", qp
->qp_num
);
1453 while ((entry
= ntb_list_rm(&qp
->ntb_tx_free_q_lock
, &qp
->tx_free_q
)))
1456 while ((entry
= ntb_list_rm(&qp
->ntb_rx_free_q_lock
, &qp
->rx_free_q
)))
1460 set_bit(free_queue
, &nt
->qp_bitmap
);
1464 EXPORT_SYMBOL_GPL(ntb_transport_create_queue
);
1467 * ntb_transport_free_queue - Frees NTB transport queue
1468 * @qp: NTB queue to be freed
1470 * Frees NTB transport queue
1472 void ntb_transport_free_queue(struct ntb_transport_qp
*qp
)
1474 struct pci_dev
*pdev
;
1475 struct ntb_queue_entry
*entry
;
1480 pdev
= ntb_query_pdev(qp
->ndev
);
1483 struct dma_chan
*chan
= qp
->dma_chan
;
1484 /* Putting the dma_chan to NULL will force any new traffic to be
1485 * processed by the CPU instead of the DAM engine
1487 qp
->dma_chan
= NULL
;
1489 /* Try to be nice and wait for any queued DMA engine
1490 * transactions to process before smashing it with a rock
1492 dma_sync_wait(chan
, qp
->last_cookie
);
1493 dmaengine_terminate_all(chan
);
1497 ntb_unregister_db_callback(qp
->ndev
, qp
->qp_num
);
1499 cancel_delayed_work_sync(&qp
->link_work
);
1501 while ((entry
= ntb_list_rm(&qp
->ntb_rx_free_q_lock
, &qp
->rx_free_q
)))
1504 while ((entry
= ntb_list_rm(&qp
->ntb_rx_pend_q_lock
, &qp
->rx_pend_q
))) {
1505 dev_warn(&pdev
->dev
, "Freeing item from a non-empty queue\n");
1509 while ((entry
= ntb_list_rm(&qp
->ntb_tx_free_q_lock
, &qp
->tx_free_q
)))
1512 set_bit(qp
->qp_num
, &qp
->transport
->qp_bitmap
);
1514 dev_info(&pdev
->dev
, "NTB Transport QP %d freed\n", qp
->qp_num
);
1516 EXPORT_SYMBOL_GPL(ntb_transport_free_queue
);
1519 * ntb_transport_rx_remove - Dequeues enqueued rx packet
1520 * @qp: NTB queue to be freed
1521 * @len: pointer to variable to write enqueued buffers length
1523 * Dequeues unused buffers from receive queue. Should only be used during
1526 * RETURNS: NULL error value on error, or void* for success.
1528 void *ntb_transport_rx_remove(struct ntb_transport_qp
*qp
, unsigned int *len
)
1530 struct ntb_queue_entry
*entry
;
1533 if (!qp
|| qp
->client_ready
== NTB_LINK_UP
)
1536 entry
= ntb_list_rm(&qp
->ntb_rx_pend_q_lock
, &qp
->rx_pend_q
);
1540 buf
= entry
->cb_data
;
1543 ntb_list_add(&qp
->ntb_rx_free_q_lock
, &entry
->entry
, &qp
->rx_free_q
);
1547 EXPORT_SYMBOL_GPL(ntb_transport_rx_remove
);
1550 * ntb_transport_rx_enqueue - Enqueue a new NTB queue entry
1551 * @qp: NTB transport layer queue the entry is to be enqueued on
1552 * @cb: per buffer pointer for callback function to use
1553 * @data: pointer to data buffer that incoming packets will be copied into
1554 * @len: length of the data buffer
1556 * Enqueue a new receive buffer onto the transport queue into which a NTB
1557 * payload can be received into.
1559 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1561 int ntb_transport_rx_enqueue(struct ntb_transport_qp
*qp
, void *cb
, void *data
,
1564 struct ntb_queue_entry
*entry
;
1569 entry
= ntb_list_rm(&qp
->ntb_rx_free_q_lock
, &qp
->rx_free_q
);
1573 entry
->cb_data
= cb
;
1577 ntb_list_add(&qp
->ntb_rx_pend_q_lock
, &entry
->entry
, &qp
->rx_pend_q
);
1581 EXPORT_SYMBOL_GPL(ntb_transport_rx_enqueue
);
1584 * ntb_transport_tx_enqueue - Enqueue a new NTB queue entry
1585 * @qp: NTB transport layer queue the entry is to be enqueued on
1586 * @cb: per buffer pointer for callback function to use
1587 * @data: pointer to data buffer that will be sent
1588 * @len: length of the data buffer
1590 * Enqueue a new transmit buffer onto the transport queue from which a NTB
1591 * payload will be transmitted. This assumes that a lock is being held to
1592 * serialize access to the qp.
1594 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1596 int ntb_transport_tx_enqueue(struct ntb_transport_qp
*qp
, void *cb
, void *data
,
1599 struct ntb_queue_entry
*entry
;
1602 if (!qp
|| qp
->qp_link
!= NTB_LINK_UP
|| !len
)
1605 entry
= ntb_list_rm(&qp
->ntb_tx_free_q_lock
, &qp
->tx_free_q
);
1607 qp
->tx_err_no_buf
++;
1611 entry
->cb_data
= cb
;
1616 rc
= ntb_process_tx(qp
, entry
);
1618 ntb_list_add(&qp
->ntb_tx_free_q_lock
, &entry
->entry
,
1623 EXPORT_SYMBOL_GPL(ntb_transport_tx_enqueue
);
1626 * ntb_transport_link_up - Notify NTB transport of client readiness to use queue
1627 * @qp: NTB transport layer queue to be enabled
1629 * Notify NTB transport layer of client readiness to use queue
1631 void ntb_transport_link_up(struct ntb_transport_qp
*qp
)
1636 qp
->client_ready
= NTB_LINK_UP
;
1638 if (qp
->transport
->transport_link
== NTB_LINK_UP
)
1639 schedule_delayed_work(&qp
->link_work
, 0);
1641 EXPORT_SYMBOL_GPL(ntb_transport_link_up
);
1644 * ntb_transport_link_down - Notify NTB transport to no longer enqueue data
1645 * @qp: NTB transport layer queue to be disabled
1647 * Notify NTB transport layer of client's desire to no longer receive data on
1648 * transport queue specified. It is the client's responsibility to ensure all
1649 * entries on queue are purged or otherwise handled appropriately.
1651 void ntb_transport_link_down(struct ntb_transport_qp
*qp
)
1653 struct pci_dev
*pdev
;
1659 pdev
= ntb_query_pdev(qp
->ndev
);
1660 qp
->client_ready
= NTB_LINK_DOWN
;
1662 rc
= ntb_read_local_spad(qp
->ndev
, QP_LINKS
, &val
);
1664 dev_err(&pdev
->dev
, "Error reading spad %d\n", QP_LINKS
);
1668 rc
= ntb_write_remote_spad(qp
->ndev
, QP_LINKS
,
1669 val
& ~(1 << qp
->qp_num
));
1671 dev_err(&pdev
->dev
, "Error writing %x to remote spad %d\n",
1672 val
& ~(1 << qp
->qp_num
), QP_LINKS
);
1674 if (qp
->qp_link
== NTB_LINK_UP
)
1675 ntb_send_link_down(qp
);
1677 cancel_delayed_work_sync(&qp
->link_work
);
1679 EXPORT_SYMBOL_GPL(ntb_transport_link_down
);
1682 * ntb_transport_link_query - Query transport link state
1683 * @qp: NTB transport layer queue to be queried
1685 * Query connectivity to the remote system of the NTB transport queue
1687 * RETURNS: true for link up or false for link down
1689 bool ntb_transport_link_query(struct ntb_transport_qp
*qp
)
1694 return qp
->qp_link
== NTB_LINK_UP
;
1696 EXPORT_SYMBOL_GPL(ntb_transport_link_query
);
1699 * ntb_transport_qp_num - Query the qp number
1700 * @qp: NTB transport layer queue to be queried
1702 * Query qp number of the NTB transport queue
1704 * RETURNS: a zero based number specifying the qp number
1706 unsigned char ntb_transport_qp_num(struct ntb_transport_qp
*qp
)
1713 EXPORT_SYMBOL_GPL(ntb_transport_qp_num
);
1716 * ntb_transport_max_size - Query the max payload size of a qp
1717 * @qp: NTB transport layer queue to be queried
1719 * Query the maximum payload size permissible on the given qp
1721 * RETURNS: the max payload size of a qp
1723 unsigned int ntb_transport_max_size(struct ntb_transport_qp
*qp
)
1731 return qp
->tx_max_frame
- sizeof(struct ntb_payload_header
);
1733 /* If DMA engine usage is possible, try to find the max size for that */
1734 max
= qp
->tx_max_frame
- sizeof(struct ntb_payload_header
);
1735 max
-= max
% (1 << qp
->dma_chan
->device
->copy_align
);
1739 EXPORT_SYMBOL_GPL(ntb_transport_max_size
);