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/dma-mapping.h>
51 #include <linux/errno.h>
52 #include <linux/export.h>
53 #include <linux/interrupt.h>
54 #include <linux/module.h>
55 #include <linux/pci.h>
56 #include <linux/slab.h>
57 #include <linux/types.h>
58 #include <linux/ntb.h>
61 #define NTB_TRANSPORT_VERSION 3
63 static unsigned int transport_mtu = 0x401E;
64 module_param(transport_mtu, uint, 0644);
65 MODULE_PARM_DESC(transport_mtu, "Maximum size of NTB transport packets");
67 static unsigned char max_num_clients = 2;
68 module_param(max_num_clients, byte, 0644);
69 MODULE_PARM_DESC(max_num_clients, "Maximum number of NTB transport clients");
71 struct ntb_queue_entry {
72 /* ntb_queue list reference */
73 struct list_head entry;
74 /* pointers to data to be transfered */
85 struct ntb_transport_qp {
86 struct ntb_transport *transport;
87 struct ntb_device *ndev;
92 u8 qp_num; /* Only 64 QP's are allowed. 0-63 */
94 struct ntb_rx_info __iomem *rx_info;
95 struct ntb_rx_info *remote_rx_info;
97 void (*tx_handler) (struct ntb_transport_qp *qp, void *qp_data,
99 struct list_head tx_free_q;
100 spinlock_t ntb_tx_free_q_lock;
102 unsigned int tx_index;
103 unsigned int tx_max_entry;
104 unsigned int tx_max_frame;
106 void (*rx_handler) (struct ntb_transport_qp *qp, void *qp_data,
107 void *data, int len);
108 struct tasklet_struct rx_work;
109 struct list_head rx_pend_q;
110 struct list_head rx_free_q;
111 spinlock_t ntb_rx_pend_q_lock;
112 spinlock_t ntb_rx_free_q_lock;
114 unsigned int rx_index;
115 unsigned int rx_max_entry;
116 unsigned int rx_max_frame;
118 void (*event_handler) (void *data, int status);
119 struct delayed_work link_work;
120 struct work_struct link_cleanup;
122 struct dentry *debugfs_dir;
123 struct dentry *debugfs_stats;
137 struct ntb_transport_mw {
143 struct ntb_transport_client_dev {
144 struct list_head entry;
148 struct ntb_transport {
149 struct list_head entry;
150 struct list_head client_devs;
152 struct ntb_device *ndev;
153 struct ntb_transport_mw mw[NTB_NUM_MW];
154 struct ntb_transport_qp *qps;
155 unsigned int max_qps;
156 unsigned long qp_bitmap;
158 struct delayed_work link_work;
159 struct work_struct link_cleanup;
163 DESC_DONE_FLAG = 1 << 0,
164 LINK_DOWN_FLAG = 1 << 1,
167 struct ntb_payload_header {
185 #define QP_TO_MW(qp) ((qp) % NTB_NUM_MW)
186 #define NTB_QP_DEF_NUM_ENTRIES 100
187 #define NTB_LINK_DOWN_TIMEOUT 10
189 static int ntb_match_bus(struct device *dev, struct device_driver *drv)
191 return !strncmp(dev_name(dev), drv->name, strlen(drv->name));
194 static int ntb_client_probe(struct device *dev)
196 const struct ntb_client *drv = container_of(dev->driver,
197 struct ntb_client, driver);
198 struct pci_dev *pdev = container_of(dev->parent, struct pci_dev, dev);
202 if (drv && drv->probe)
203 rc = drv->probe(pdev);
210 static int ntb_client_remove(struct device *dev)
212 const struct ntb_client *drv = container_of(dev->driver,
213 struct ntb_client, driver);
214 struct pci_dev *pdev = container_of(dev->parent, struct pci_dev, dev);
216 if (drv && drv->remove)
224 static struct bus_type ntb_bus_type = {
226 .match = ntb_match_bus,
227 .probe = ntb_client_probe,
228 .remove = ntb_client_remove,
231 static LIST_HEAD(ntb_transport_list);
233 static int ntb_bus_init(struct ntb_transport *nt)
235 if (list_empty(&ntb_transport_list)) {
236 int rc = bus_register(&ntb_bus_type);
241 list_add(&nt->entry, &ntb_transport_list);
246 static void ntb_bus_remove(struct ntb_transport *nt)
248 struct ntb_transport_client_dev *client_dev, *cd;
250 list_for_each_entry_safe(client_dev, cd, &nt->client_devs, entry) {
251 dev_err(client_dev->dev.parent, "%s still attached to bus, removing\n",
252 dev_name(&client_dev->dev));
253 list_del(&client_dev->entry);
254 device_unregister(&client_dev->dev);
257 list_del(&nt->entry);
259 if (list_empty(&ntb_transport_list))
260 bus_unregister(&ntb_bus_type);
263 static void ntb_client_release(struct device *dev)
265 struct ntb_transport_client_dev *client_dev;
266 client_dev = container_of(dev, struct ntb_transport_client_dev, dev);
272 * ntb_unregister_client_dev - Unregister NTB client device
273 * @device_name: Name of NTB client device
275 * Unregister an NTB client device with the NTB transport layer
277 void ntb_unregister_client_dev(char *device_name)
279 struct ntb_transport_client_dev *client, *cd;
280 struct ntb_transport *nt;
282 list_for_each_entry(nt, &ntb_transport_list, entry)
283 list_for_each_entry_safe(client, cd, &nt->client_devs, entry)
284 if (!strncmp(dev_name(&client->dev), device_name,
285 strlen(device_name))) {
286 list_del(&client->entry);
287 device_unregister(&client->dev);
290 EXPORT_SYMBOL_GPL(ntb_unregister_client_dev);
293 * ntb_register_client_dev - Register NTB client device
294 * @device_name: Name of NTB client device
296 * Register an NTB client device with the NTB transport layer
298 int ntb_register_client_dev(char *device_name)
300 struct ntb_transport_client_dev *client_dev;
301 struct ntb_transport *nt;
304 if (list_empty(&ntb_transport_list))
307 list_for_each_entry(nt, &ntb_transport_list, entry) {
310 client_dev = kzalloc(sizeof(struct ntb_transport_client_dev),
317 dev = &client_dev->dev;
319 /* setup and register client devices */
320 dev_set_name(dev, "%s%d", device_name, i);
321 dev->bus = &ntb_bus_type;
322 dev->release = ntb_client_release;
323 dev->parent = &ntb_query_pdev(nt->ndev)->dev;
325 rc = device_register(dev);
331 list_add_tail(&client_dev->entry, &nt->client_devs);
338 ntb_unregister_client_dev(device_name);
342 EXPORT_SYMBOL_GPL(ntb_register_client_dev);
345 * ntb_register_client - Register NTB client driver
346 * @drv: NTB client driver to be registered
348 * Register an NTB client driver with the NTB transport layer
350 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
352 int ntb_register_client(struct ntb_client *drv)
354 drv->driver.bus = &ntb_bus_type;
356 if (list_empty(&ntb_transport_list))
359 return driver_register(&drv->driver);
361 EXPORT_SYMBOL_GPL(ntb_register_client);
364 * ntb_unregister_client - Unregister NTB client driver
365 * @drv: NTB client driver to be unregistered
367 * Unregister an NTB client driver with the NTB transport layer
369 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
371 void ntb_unregister_client(struct ntb_client *drv)
373 driver_unregister(&drv->driver);
375 EXPORT_SYMBOL_GPL(ntb_unregister_client);
377 static ssize_t debugfs_read(struct file *filp, char __user *ubuf, size_t count,
380 struct ntb_transport_qp *qp;
382 ssize_t ret, out_offset, out_count;
386 buf = kmalloc(out_count, GFP_KERNEL);
390 qp = filp->private_data;
392 out_offset += snprintf(buf + out_offset, out_count - out_offset,
394 out_offset += snprintf(buf + out_offset, out_count - out_offset,
395 "rx_bytes - \t%llu\n", qp->rx_bytes);
396 out_offset += snprintf(buf + out_offset, out_count - out_offset,
397 "rx_pkts - \t%llu\n", qp->rx_pkts);
398 out_offset += snprintf(buf + out_offset, out_count - out_offset,
399 "rx_ring_empty - %llu\n", qp->rx_ring_empty);
400 out_offset += snprintf(buf + out_offset, out_count - out_offset,
401 "rx_err_no_buf - %llu\n", qp->rx_err_no_buf);
402 out_offset += snprintf(buf + out_offset, out_count - out_offset,
403 "rx_err_oflow - \t%llu\n", qp->rx_err_oflow);
404 out_offset += snprintf(buf + out_offset, out_count - out_offset,
405 "rx_err_ver - \t%llu\n", qp->rx_err_ver);
406 out_offset += snprintf(buf + out_offset, out_count - out_offset,
407 "rx_buff - \t%p\n", qp->rx_buff);
408 out_offset += snprintf(buf + out_offset, out_count - out_offset,
409 "rx_index - \t%u\n", qp->rx_index);
410 out_offset += snprintf(buf + out_offset, out_count - out_offset,
411 "rx_max_entry - \t%u\n", qp->rx_max_entry);
413 out_offset += snprintf(buf + out_offset, out_count - out_offset,
414 "tx_bytes - \t%llu\n", qp->tx_bytes);
415 out_offset += snprintf(buf + out_offset, out_count - out_offset,
416 "tx_pkts - \t%llu\n", qp->tx_pkts);
417 out_offset += snprintf(buf + out_offset, out_count - out_offset,
418 "tx_ring_full - \t%llu\n", qp->tx_ring_full);
419 out_offset += snprintf(buf + out_offset, out_count - out_offset,
420 "tx_mw - \t%p\n", qp->tx_mw);
421 out_offset += snprintf(buf + out_offset, out_count - out_offset,
422 "tx_index - \t%u\n", qp->tx_index);
423 out_offset += snprintf(buf + out_offset, out_count - out_offset,
424 "tx_max_entry - \t%u\n", qp->tx_max_entry);
426 out_offset += snprintf(buf + out_offset, out_count - out_offset,
427 "\nQP Link %s\n", (qp->qp_link == NTB_LINK_UP) ?
429 if (out_offset > out_count)
430 out_offset = out_count;
432 ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset);
437 static const struct file_operations ntb_qp_debugfs_stats = {
438 .owner = THIS_MODULE,
440 .read = debugfs_read,
443 static void ntb_list_add(spinlock_t *lock, struct list_head *entry,
444 struct list_head *list)
448 spin_lock_irqsave(lock, flags);
449 list_add_tail(entry, list);
450 spin_unlock_irqrestore(lock, flags);
453 static struct ntb_queue_entry *ntb_list_rm(spinlock_t *lock,
454 struct list_head *list)
456 struct ntb_queue_entry *entry;
459 spin_lock_irqsave(lock, flags);
460 if (list_empty(list)) {
464 entry = list_first_entry(list, struct ntb_queue_entry, entry);
465 list_del(&entry->entry);
467 spin_unlock_irqrestore(lock, flags);
472 static void ntb_transport_setup_qp_mw(struct ntb_transport *nt,
475 struct ntb_transport_qp *qp = &nt->qps[qp_num];
476 unsigned int rx_size, num_qps_mw;
477 u8 mw_num = QP_TO_MW(qp_num);
480 WARN_ON(nt->mw[mw_num].virt_addr == NULL);
482 if (nt->max_qps % NTB_NUM_MW && mw_num < nt->max_qps % NTB_NUM_MW)
483 num_qps_mw = nt->max_qps / NTB_NUM_MW + 1;
485 num_qps_mw = nt->max_qps / NTB_NUM_MW;
487 rx_size = (unsigned int) nt->mw[mw_num].size / num_qps_mw;
488 qp->remote_rx_info = nt->mw[mw_num].virt_addr +
489 (qp_num / NTB_NUM_MW * rx_size);
490 rx_size -= sizeof(struct ntb_rx_info);
492 qp->rx_buff = qp->remote_rx_info + 1;
493 /* Due to housekeeping, there must be atleast 2 buffs */
494 qp->rx_max_frame = min(transport_mtu, rx_size / 2);
495 qp->rx_max_entry = rx_size / qp->rx_max_frame;
498 qp->remote_rx_info->entry = qp->rx_max_entry - 1;
500 /* setup the hdr offsets with 0's */
501 for (i = 0; i < qp->rx_max_entry; i++) {
502 void *offset = qp->rx_buff + qp->rx_max_frame * (i + 1) -
503 sizeof(struct ntb_payload_header);
504 memset(offset, 0, sizeof(struct ntb_payload_header));
512 static void ntb_free_mw(struct ntb_transport *nt, int num_mw)
514 struct ntb_transport_mw *mw = &nt->mw[num_mw];
515 struct pci_dev *pdev = ntb_query_pdev(nt->ndev);
520 dma_free_coherent(&pdev->dev, mw->size, mw->virt_addr, mw->dma_addr);
521 mw->virt_addr = NULL;
524 static int ntb_set_mw(struct ntb_transport *nt, int num_mw, unsigned int size)
526 struct ntb_transport_mw *mw = &nt->mw[num_mw];
527 struct pci_dev *pdev = ntb_query_pdev(nt->ndev);
529 /* No need to re-setup */
530 if (mw->size == ALIGN(size, 4096))
534 ntb_free_mw(nt, num_mw);
536 /* Alloc memory for receiving data. Must be 4k aligned */
537 mw->size = ALIGN(size, 4096);
539 mw->virt_addr = dma_alloc_coherent(&pdev->dev, mw->size, &mw->dma_addr,
541 if (!mw->virt_addr) {
543 dev_err(&pdev->dev, "Unable to allocate MW buffer of size %d\n",
548 /* Notify HW the memory location of the receive buffer */
549 ntb_set_mw_addr(nt->ndev, num_mw, mw->dma_addr);
554 static void ntb_qp_link_cleanup(struct work_struct *work)
556 struct ntb_transport_qp *qp = container_of(work,
557 struct ntb_transport_qp,
559 struct ntb_transport *nt = qp->transport;
560 struct pci_dev *pdev = ntb_query_pdev(nt->ndev);
562 if (qp->qp_link == NTB_LINK_DOWN) {
563 cancel_delayed_work_sync(&qp->link_work);
567 if (qp->event_handler)
568 qp->event_handler(qp->cb_data, NTB_LINK_DOWN);
570 dev_info(&pdev->dev, "qp %d: Link Down\n", qp->qp_num);
571 qp->qp_link = NTB_LINK_DOWN;
573 if (nt->transport_link == NTB_LINK_UP)
574 schedule_delayed_work(&qp->link_work,
575 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT));
578 static void ntb_qp_link_down(struct ntb_transport_qp *qp)
580 schedule_work(&qp->link_cleanup);
583 static void ntb_transport_link_cleanup(struct work_struct *work)
585 struct ntb_transport *nt = container_of(work, struct ntb_transport,
589 if (nt->transport_link == NTB_LINK_DOWN)
590 cancel_delayed_work_sync(&nt->link_work);
592 nt->transport_link = NTB_LINK_DOWN;
594 /* Pass along the info to any clients */
595 for (i = 0; i < nt->max_qps; i++)
596 if (!test_bit(i, &nt->qp_bitmap))
597 ntb_qp_link_down(&nt->qps[i]);
599 /* The scratchpad registers keep the values if the remote side
600 * goes down, blast them now to give them a sane value the next
601 * time they are accessed
603 for (i = 0; i < MAX_SPAD; i++)
604 ntb_write_local_spad(nt->ndev, i, 0);
607 static void ntb_transport_event_callback(void *data, enum ntb_hw_event event)
609 struct ntb_transport *nt = data;
612 case NTB_EVENT_HW_LINK_UP:
613 schedule_delayed_work(&nt->link_work, 0);
615 case NTB_EVENT_HW_LINK_DOWN:
616 schedule_work(&nt->link_cleanup);
623 static void ntb_transport_link_work(struct work_struct *work)
625 struct ntb_transport *nt = container_of(work, struct ntb_transport,
627 struct ntb_device *ndev = nt->ndev;
628 struct pci_dev *pdev = ntb_query_pdev(ndev);
632 /* send the local info, in the opposite order of the way we read it */
633 for (i = 0; i < NTB_NUM_MW; i++) {
634 rc = ntb_write_remote_spad(ndev, MW0_SZ_HIGH + (i * 2),
635 ntb_get_mw_size(ndev, i) >> 32);
637 dev_err(&pdev->dev, "Error writing %u to remote spad %d\n",
638 (u32)(ntb_get_mw_size(ndev, i) >> 32),
639 MW0_SZ_HIGH + (i * 2));
643 rc = ntb_write_remote_spad(ndev, MW0_SZ_LOW + (i * 2),
644 (u32) ntb_get_mw_size(ndev, i));
646 dev_err(&pdev->dev, "Error writing %u to remote spad %d\n",
647 (u32) ntb_get_mw_size(ndev, i),
648 MW0_SZ_LOW + (i * 2));
653 rc = ntb_write_remote_spad(ndev, NUM_MWS, NTB_NUM_MW);
655 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n",
656 NTB_NUM_MW, NUM_MWS);
660 rc = ntb_write_remote_spad(ndev, NUM_QPS, nt->max_qps);
662 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n",
663 nt->max_qps, NUM_QPS);
667 rc = ntb_write_remote_spad(ndev, VERSION, NTB_TRANSPORT_VERSION);
669 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n",
670 NTB_TRANSPORT_VERSION, VERSION);
674 /* Query the remote side for its info */
675 rc = ntb_read_remote_spad(ndev, VERSION, &val);
677 dev_err(&pdev->dev, "Error reading remote spad %d\n", VERSION);
681 if (val != NTB_TRANSPORT_VERSION)
683 dev_dbg(&pdev->dev, "Remote version = %d\n", val);
685 rc = ntb_read_remote_spad(ndev, NUM_QPS, &val);
687 dev_err(&pdev->dev, "Error reading remote spad %d\n", NUM_QPS);
691 if (val != nt->max_qps)
693 dev_dbg(&pdev->dev, "Remote max number of qps = %d\n", val);
695 rc = ntb_read_remote_spad(ndev, NUM_MWS, &val);
697 dev_err(&pdev->dev, "Error reading remote spad %d\n", NUM_MWS);
701 if (val != NTB_NUM_MW)
703 dev_dbg(&pdev->dev, "Remote number of mws = %d\n", val);
705 for (i = 0; i < NTB_NUM_MW; i++) {
708 rc = ntb_read_remote_spad(ndev, MW0_SZ_HIGH + (i * 2), &val);
710 dev_err(&pdev->dev, "Error reading remote spad %d\n",
711 MW0_SZ_HIGH + (i * 2));
715 val64 = (u64) val << 32;
717 rc = ntb_read_remote_spad(ndev, MW0_SZ_LOW + (i * 2), &val);
719 dev_err(&pdev->dev, "Error reading remote spad %d\n",
720 MW0_SZ_LOW + (i * 2));
726 dev_dbg(&pdev->dev, "Remote MW%d size = %llu\n", i, val64);
728 rc = ntb_set_mw(nt, i, val64);
733 nt->transport_link = NTB_LINK_UP;
735 for (i = 0; i < nt->max_qps; i++) {
736 struct ntb_transport_qp *qp = &nt->qps[i];
738 ntb_transport_setup_qp_mw(nt, i);
740 if (qp->client_ready == NTB_LINK_UP)
741 schedule_delayed_work(&qp->link_work, 0);
747 for (i = 0; i < NTB_NUM_MW; i++)
750 if (ntb_hw_link_status(ndev))
751 schedule_delayed_work(&nt->link_work,
752 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT));
755 static void ntb_qp_link_work(struct work_struct *work)
757 struct ntb_transport_qp *qp = container_of(work,
758 struct ntb_transport_qp,
760 struct pci_dev *pdev = ntb_query_pdev(qp->ndev);
761 struct ntb_transport *nt = qp->transport;
764 WARN_ON(nt->transport_link != NTB_LINK_UP);
766 rc = ntb_read_local_spad(nt->ndev, QP_LINKS, &val);
768 dev_err(&pdev->dev, "Error reading spad %d\n", QP_LINKS);
772 rc = ntb_write_remote_spad(nt->ndev, QP_LINKS, val | 1 << qp->qp_num);
774 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n",
775 val | 1 << qp->qp_num, QP_LINKS);
777 /* query remote spad for qp ready bits */
778 rc = ntb_read_remote_spad(nt->ndev, QP_LINKS, &val);
780 dev_err(&pdev->dev, "Error reading remote spad %d\n", QP_LINKS);
782 dev_dbg(&pdev->dev, "Remote QP link status = %x\n", val);
784 /* See if the remote side is up */
785 if (1 << qp->qp_num & val) {
786 qp->qp_link = NTB_LINK_UP;
788 dev_info(&pdev->dev, "qp %d: Link Up\n", qp->qp_num);
789 if (qp->event_handler)
790 qp->event_handler(qp->cb_data, NTB_LINK_UP);
791 } else if (nt->transport_link == NTB_LINK_UP)
792 schedule_delayed_work(&qp->link_work,
793 msecs_to_jiffies(NTB_LINK_DOWN_TIMEOUT));
796 static void ntb_transport_init_queue(struct ntb_transport *nt,
799 struct ntb_transport_qp *qp;
800 unsigned int num_qps_mw, tx_size;
801 u8 mw_num = QP_TO_MW(qp_num);
803 qp = &nt->qps[qp_num];
807 qp->qp_link = NTB_LINK_DOWN;
808 qp->client_ready = NTB_LINK_DOWN;
809 qp->event_handler = NULL;
811 if (nt->max_qps % NTB_NUM_MW && mw_num < nt->max_qps % NTB_NUM_MW)
812 num_qps_mw = nt->max_qps / NTB_NUM_MW + 1;
814 num_qps_mw = nt->max_qps / NTB_NUM_MW;
816 tx_size = (unsigned int) ntb_get_mw_size(qp->ndev, mw_num) / num_qps_mw;
817 qp->rx_info = ntb_get_mw_vbase(nt->ndev, mw_num) +
818 (qp_num / NTB_NUM_MW * tx_size);
819 tx_size -= sizeof(struct ntb_rx_info);
821 qp->tx_mw = qp->rx_info + 1;
822 /* Due to housekeeping, there must be atleast 2 buffs */
823 qp->tx_max_frame = min(transport_mtu, tx_size / 2);
824 qp->tx_max_entry = tx_size / qp->tx_max_frame;
826 if (ntb_query_debugfs(nt->ndev)) {
827 char debugfs_name[4];
829 snprintf(debugfs_name, 4, "qp%d", qp_num);
830 qp->debugfs_dir = debugfs_create_dir(debugfs_name,
831 ntb_query_debugfs(nt->ndev));
833 qp->debugfs_stats = debugfs_create_file("stats", S_IRUSR,
835 &ntb_qp_debugfs_stats);
838 INIT_DELAYED_WORK(&qp->link_work, ntb_qp_link_work);
839 INIT_WORK(&qp->link_cleanup, ntb_qp_link_cleanup);
841 spin_lock_init(&qp->ntb_rx_pend_q_lock);
842 spin_lock_init(&qp->ntb_rx_free_q_lock);
843 spin_lock_init(&qp->ntb_tx_free_q_lock);
845 INIT_LIST_HEAD(&qp->rx_pend_q);
846 INIT_LIST_HEAD(&qp->rx_free_q);
847 INIT_LIST_HEAD(&qp->tx_free_q);
850 int ntb_transport_init(struct pci_dev *pdev)
852 struct ntb_transport *nt;
855 nt = kzalloc(sizeof(struct ntb_transport), GFP_KERNEL);
859 nt->ndev = ntb_register_transport(pdev, nt);
865 nt->max_qps = min(nt->ndev->max_cbs, max_num_clients);
867 nt->qps = kcalloc(nt->max_qps, sizeof(struct ntb_transport_qp),
874 nt->qp_bitmap = ((u64) 1 << nt->max_qps) - 1;
876 for (i = 0; i < nt->max_qps; i++)
877 ntb_transport_init_queue(nt, i);
879 INIT_DELAYED_WORK(&nt->link_work, ntb_transport_link_work);
880 INIT_WORK(&nt->link_cleanup, ntb_transport_link_cleanup);
882 rc = ntb_register_event_callback(nt->ndev,
883 ntb_transport_event_callback);
887 INIT_LIST_HEAD(&nt->client_devs);
888 rc = ntb_bus_init(nt);
892 if (ntb_hw_link_status(nt->ndev))
893 schedule_delayed_work(&nt->link_work, 0);
898 ntb_unregister_event_callback(nt->ndev);
902 ntb_unregister_transport(nt->ndev);
908 void ntb_transport_free(void *transport)
910 struct ntb_transport *nt = transport;
911 struct pci_dev *pdev;
914 nt->transport_link = NTB_LINK_DOWN;
916 /* verify that all the qp's are freed */
917 for (i = 0; i < nt->max_qps; i++) {
918 if (!test_bit(i, &nt->qp_bitmap))
919 ntb_transport_free_queue(&nt->qps[i]);
920 debugfs_remove_recursive(nt->qps[i].debugfs_dir);
925 cancel_delayed_work_sync(&nt->link_work);
927 ntb_unregister_event_callback(nt->ndev);
929 pdev = ntb_query_pdev(nt->ndev);
931 for (i = 0; i < NTB_NUM_MW; i++)
935 ntb_unregister_transport(nt->ndev);
939 static void ntb_rx_copy_task(struct ntb_transport_qp *qp,
940 struct ntb_queue_entry *entry, void *offset)
942 void *cb_data = entry->cb_data;
943 unsigned int len = entry->len;
945 memcpy(entry->buf, offset, entry->len);
947 ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, &qp->rx_free_q);
949 if (qp->rx_handler && qp->client_ready == NTB_LINK_UP)
950 qp->rx_handler(qp, qp->cb_data, cb_data, len);
953 static int ntb_process_rxc(struct ntb_transport_qp *qp)
955 struct ntb_payload_header *hdr;
956 struct ntb_queue_entry *entry;
959 offset = qp->rx_buff + qp->rx_max_frame * qp->rx_index;
960 hdr = offset + qp->rx_max_frame - sizeof(struct ntb_payload_header);
962 entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q);
964 dev_dbg(&ntb_query_pdev(qp->ndev)->dev,
965 "no buffer - HDR ver %u, len %d, flags %x\n",
966 hdr->ver, hdr->len, hdr->flags);
971 if (!(hdr->flags & DESC_DONE_FLAG)) {
972 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry,
978 if (hdr->ver != (u32) qp->rx_pkts) {
979 dev_dbg(&ntb_query_pdev(qp->ndev)->dev,
980 "qp %d: version mismatch, expected %llu - got %u\n",
981 qp->qp_num, qp->rx_pkts, hdr->ver);
982 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry,
988 if (hdr->flags & LINK_DOWN_FLAG) {
989 ntb_qp_link_down(qp);
991 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry,
996 dev_dbg(&ntb_query_pdev(qp->ndev)->dev,
997 "rx offset %u, ver %u - %d payload received, buf size %d\n",
998 qp->rx_index, hdr->ver, hdr->len, entry->len);
1000 if (hdr->len <= entry->len) {
1001 entry->len = hdr->len;
1002 ntb_rx_copy_task(qp, entry, offset);
1004 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry,
1008 dev_dbg(&ntb_query_pdev(qp->ndev)->dev,
1009 "RX overflow! Wanted %d got %d\n",
1010 hdr->len, entry->len);
1013 qp->rx_bytes += hdr->len;
1017 /* Ensure that the data is fully copied out before clearing the flag */
1020 iowrite32(qp->rx_index, &qp->rx_info->entry);
1023 qp->rx_index %= qp->rx_max_entry;
1028 static void ntb_transport_rx(unsigned long data)
1030 struct ntb_transport_qp *qp = (struct ntb_transport_qp *)data;
1033 /* Limit the number of packets processed in a single interrupt to
1034 * provide fairness to others
1036 for (i = 0; i < qp->rx_max_entry; i++) {
1037 rc = ntb_process_rxc(qp);
1043 static void ntb_transport_rxc_db(void *data, int db_num)
1045 struct ntb_transport_qp *qp = data;
1047 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%s: doorbell %d received\n",
1050 tasklet_schedule(&qp->rx_work);
1053 static void ntb_tx_copy_task(struct ntb_transport_qp *qp,
1054 struct ntb_queue_entry *entry,
1055 void __iomem *offset)
1057 struct ntb_payload_header __iomem *hdr;
1059 memcpy_toio(offset, entry->buf, entry->len);
1061 hdr = offset + qp->tx_max_frame - sizeof(struct ntb_payload_header);
1062 iowrite32(entry->len, &hdr->len);
1063 iowrite32((u32) qp->tx_pkts, &hdr->ver);
1065 /* Ensure that the data is fully copied out before setting the flag */
1067 iowrite32(entry->flags | DESC_DONE_FLAG, &hdr->flags);
1069 ntb_ring_sdb(qp->ndev, qp->qp_num);
1071 /* The entry length can only be zero if the packet is intended to be a
1072 * "link down" or similar. Since no payload is being sent in these
1073 * cases, there is nothing to add to the completion queue.
1075 if (entry->len > 0) {
1076 qp->tx_bytes += entry->len;
1079 qp->tx_handler(qp, qp->cb_data, entry->cb_data,
1083 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry, &qp->tx_free_q);
1086 static int ntb_process_tx(struct ntb_transport_qp *qp,
1087 struct ntb_queue_entry *entry)
1089 void __iomem *offset;
1091 offset = qp->tx_mw + qp->tx_max_frame * qp->tx_index;
1093 dev_dbg(&ntb_query_pdev(qp->ndev)->dev, "%lld - offset %p, tx %u, entry len %d flags %x buff %p\n",
1094 qp->tx_pkts, offset, qp->tx_index, entry->len, entry->flags,
1096 if (qp->tx_index == qp->remote_rx_info->entry) {
1101 if (entry->len > qp->tx_max_frame - sizeof(struct ntb_payload_header)) {
1103 qp->tx_handler(qp->cb_data, qp, NULL, -EIO);
1105 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry,
1110 ntb_tx_copy_task(qp, entry, offset);
1113 qp->tx_index %= qp->tx_max_entry;
1120 static void ntb_send_link_down(struct ntb_transport_qp *qp)
1122 struct pci_dev *pdev = ntb_query_pdev(qp->ndev);
1123 struct ntb_queue_entry *entry;
1126 if (qp->qp_link == NTB_LINK_DOWN)
1129 qp->qp_link = NTB_LINK_DOWN;
1130 dev_info(&pdev->dev, "qp %d: Link Down\n", qp->qp_num);
1132 for (i = 0; i < NTB_LINK_DOWN_TIMEOUT; i++) {
1133 entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q);
1142 entry->cb_data = NULL;
1145 entry->flags = LINK_DOWN_FLAG;
1147 rc = ntb_process_tx(qp, entry);
1149 dev_err(&pdev->dev, "ntb: QP%d unable to send linkdown msg\n",
1154 * ntb_transport_create_queue - Create a new NTB transport layer queue
1155 * @rx_handler: receive callback function
1156 * @tx_handler: transmit callback function
1157 * @event_handler: event callback function
1159 * Create a new NTB transport layer queue and provide the queue with a callback
1160 * routine for both transmit and receive. The receive callback routine will be
1161 * used to pass up data when the transport has received it on the queue. The
1162 * transmit callback routine will be called when the transport has completed the
1163 * transmission of the data on the queue and the data is ready to be freed.
1165 * RETURNS: pointer to newly created ntb_queue, NULL on error.
1167 struct ntb_transport_qp *
1168 ntb_transport_create_queue(void *data, struct pci_dev *pdev,
1169 const struct ntb_queue_handlers *handlers)
1171 struct ntb_queue_entry *entry;
1172 struct ntb_transport_qp *qp;
1173 struct ntb_transport *nt;
1174 unsigned int free_queue;
1177 nt = ntb_find_transport(pdev);
1181 free_queue = ffs(nt->qp_bitmap);
1185 /* decrement free_queue to make it zero based */
1188 clear_bit(free_queue, &nt->qp_bitmap);
1190 qp = &nt->qps[free_queue];
1192 qp->rx_handler = handlers->rx_handler;
1193 qp->tx_handler = handlers->tx_handler;
1194 qp->event_handler = handlers->event_handler;
1196 for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) {
1197 entry = kzalloc(sizeof(struct ntb_queue_entry), GFP_ATOMIC);
1201 ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry,
1205 for (i = 0; i < NTB_QP_DEF_NUM_ENTRIES; i++) {
1206 entry = kzalloc(sizeof(struct ntb_queue_entry), GFP_ATOMIC);
1210 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry,
1214 tasklet_init(&qp->rx_work, ntb_transport_rx, (unsigned long) qp);
1216 rc = ntb_register_db_callback(qp->ndev, free_queue, qp,
1217 ntb_transport_rxc_db);
1221 dev_info(&pdev->dev, "NTB Transport QP %d created\n", qp->qp_num);
1226 tasklet_disable(&qp->rx_work);
1228 while ((entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q)))
1231 while ((entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q)))
1233 set_bit(free_queue, &nt->qp_bitmap);
1237 EXPORT_SYMBOL_GPL(ntb_transport_create_queue);
1240 * ntb_transport_free_queue - Frees NTB transport queue
1241 * @qp: NTB queue to be freed
1243 * Frees NTB transport queue
1245 void ntb_transport_free_queue(struct ntb_transport_qp *qp)
1247 struct pci_dev *pdev;
1248 struct ntb_queue_entry *entry;
1253 pdev = ntb_query_pdev(qp->ndev);
1255 cancel_delayed_work_sync(&qp->link_work);
1257 ntb_unregister_db_callback(qp->ndev, qp->qp_num);
1258 tasklet_disable(&qp->rx_work);
1260 while ((entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q)))
1263 while ((entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q))) {
1264 dev_warn(&pdev->dev, "Freeing item from a non-empty queue\n");
1268 while ((entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q)))
1271 set_bit(qp->qp_num, &qp->transport->qp_bitmap);
1273 dev_info(&pdev->dev, "NTB Transport QP %d freed\n", qp->qp_num);
1275 EXPORT_SYMBOL_GPL(ntb_transport_free_queue);
1278 * ntb_transport_rx_remove - Dequeues enqueued rx packet
1279 * @qp: NTB queue to be freed
1280 * @len: pointer to variable to write enqueued buffers length
1282 * Dequeues unused buffers from receive queue. Should only be used during
1285 * RETURNS: NULL error value on error, or void* for success.
1287 void *ntb_transport_rx_remove(struct ntb_transport_qp *qp, unsigned int *len)
1289 struct ntb_queue_entry *entry;
1292 if (!qp || qp->client_ready == NTB_LINK_UP)
1295 entry = ntb_list_rm(&qp->ntb_rx_pend_q_lock, &qp->rx_pend_q);
1299 buf = entry->cb_data;
1302 ntb_list_add(&qp->ntb_rx_free_q_lock, &entry->entry, &qp->rx_free_q);
1306 EXPORT_SYMBOL_GPL(ntb_transport_rx_remove);
1309 * ntb_transport_rx_enqueue - Enqueue a new NTB queue entry
1310 * @qp: NTB transport layer queue the entry is to be enqueued on
1311 * @cb: per buffer pointer for callback function to use
1312 * @data: pointer to data buffer that incoming packets will be copied into
1313 * @len: length of the data buffer
1315 * Enqueue a new receive buffer onto the transport queue into which a NTB
1316 * payload can be received into.
1318 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1320 int ntb_transport_rx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data,
1323 struct ntb_queue_entry *entry;
1328 entry = ntb_list_rm(&qp->ntb_rx_free_q_lock, &qp->rx_free_q);
1332 entry->cb_data = cb;
1336 ntb_list_add(&qp->ntb_rx_pend_q_lock, &entry->entry, &qp->rx_pend_q);
1340 EXPORT_SYMBOL_GPL(ntb_transport_rx_enqueue);
1343 * ntb_transport_tx_enqueue - Enqueue a new NTB queue entry
1344 * @qp: NTB transport layer queue the entry is to be enqueued on
1345 * @cb: per buffer pointer for callback function to use
1346 * @data: pointer to data buffer that will be sent
1347 * @len: length of the data buffer
1349 * Enqueue a new transmit buffer onto the transport queue from which a NTB
1350 * payload will be transmitted. This assumes that a lock is behing held to
1351 * serialize access to the qp.
1353 * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
1355 int ntb_transport_tx_enqueue(struct ntb_transport_qp *qp, void *cb, void *data,
1358 struct ntb_queue_entry *entry;
1361 if (!qp || qp->qp_link != NTB_LINK_UP || !len)
1364 entry = ntb_list_rm(&qp->ntb_tx_free_q_lock, &qp->tx_free_q);
1368 entry->cb_data = cb;
1373 rc = ntb_process_tx(qp, entry);
1375 ntb_list_add(&qp->ntb_tx_free_q_lock, &entry->entry,
1380 EXPORT_SYMBOL_GPL(ntb_transport_tx_enqueue);
1383 * ntb_transport_link_up - Notify NTB transport of client readiness to use queue
1384 * @qp: NTB transport layer queue to be enabled
1386 * Notify NTB transport layer of client readiness to use queue
1388 void ntb_transport_link_up(struct ntb_transport_qp *qp)
1393 qp->client_ready = NTB_LINK_UP;
1395 if (qp->transport->transport_link == NTB_LINK_UP)
1396 schedule_delayed_work(&qp->link_work, 0);
1398 EXPORT_SYMBOL_GPL(ntb_transport_link_up);
1401 * ntb_transport_link_down - Notify NTB transport to no longer enqueue data
1402 * @qp: NTB transport layer queue to be disabled
1404 * Notify NTB transport layer of client's desire to no longer receive data on
1405 * transport queue specified. It is the client's responsibility to ensure all
1406 * entries on queue are purged or otherwise handled appropraitely.
1408 void ntb_transport_link_down(struct ntb_transport_qp *qp)
1410 struct pci_dev *pdev;
1416 pdev = ntb_query_pdev(qp->ndev);
1417 qp->client_ready = NTB_LINK_DOWN;
1419 rc = ntb_read_local_spad(qp->ndev, QP_LINKS, &val);
1421 dev_err(&pdev->dev, "Error reading spad %d\n", QP_LINKS);
1425 rc = ntb_write_remote_spad(qp->ndev, QP_LINKS,
1426 val & ~(1 << qp->qp_num));
1428 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n",
1429 val & ~(1 << qp->qp_num), QP_LINKS);
1431 if (qp->qp_link == NTB_LINK_UP)
1432 ntb_send_link_down(qp);
1434 cancel_delayed_work_sync(&qp->link_work);
1436 EXPORT_SYMBOL_GPL(ntb_transport_link_down);
1439 * ntb_transport_link_query - Query transport link state
1440 * @qp: NTB transport layer queue to be queried
1442 * Query connectivity to the remote system of the NTB transport queue
1444 * RETURNS: true for link up or false for link down
1446 bool ntb_transport_link_query(struct ntb_transport_qp *qp)
1451 return qp->qp_link == NTB_LINK_UP;
1453 EXPORT_SYMBOL_GPL(ntb_transport_link_query);
1456 * ntb_transport_qp_num - Query the qp number
1457 * @qp: NTB transport layer queue to be queried
1459 * Query qp number of the NTB transport queue
1461 * RETURNS: a zero based number specifying the qp number
1463 unsigned char ntb_transport_qp_num(struct ntb_transport_qp *qp)
1470 EXPORT_SYMBOL_GPL(ntb_transport_qp_num);
1473 * ntb_transport_max_size - Query the max payload size of a qp
1474 * @qp: NTB transport layer queue to be queried
1476 * Query the maximum payload size permissible on the given qp
1478 * RETURNS: the max payload size of a qp
1480 unsigned int ntb_transport_max_size(struct ntb_transport_qp *qp)
1485 return qp->tx_max_frame - sizeof(struct ntb_payload_header);
1487 EXPORT_SYMBOL_GPL(ntb_transport_max_size);