1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Endpoint Function Driver to implement Non-Transparent Bridge functionality
4 *
5 * Copyright (C) 2020 Texas Instruments
6 * Author: Kishon Vijay Abraham I <kishon@ti.com>
7 */
8
9 /*
10 * The PCI NTB function driver configures the SoC with multiple PCIe Endpoint
11 * (EP) controller instances (see diagram below) in such a way that
12 * transactions from one EP controller are routed to the other EP controller.
13 * Once PCI NTB function driver configures the SoC with multiple EP instances,
14 * HOST1 and HOST2 can communicate with each other using SoC as a bridge.
15 *
16 * +-------------+ +-------------+
17 * | | | |
18 * | HOST1 | | HOST2 |
19 * | | | |
20 * +------^------+ +------^------+
21 * | |
22 * | |
23 * +---------|-------------------------------------------------|---------+
24 * | +------v------+ +------v------+ |
25 * | | | | | |
26 * | | EP | | EP | |
27 * | | CONTROLLER1 | | CONTROLLER2 | |
28 * | | <-----------------------------------> | |
29 * | | | | | |
30 * | | | | | |
31 * | | | SoC With Multiple EP Instances | | |
32 * | | | (Configured using NTB Function) | | |
33 * | +-------------+ +-------------+ |
34 * +---------------------------------------------------------------------+
35 */
36
37 #include <linux/delay.h>
38 #include <linux/io.h>
39 #include <linux/module.h>
40 #include <linux/slab.h>
41
42 #include <linux/pci-epc.h>
43 #include <linux/pci-epf.h>
44
45 static struct workqueue_struct *kpcintb_workqueue;
46
47 #define COMMAND_CONFIGURE_DOORBELL 1
48 #define COMMAND_TEARDOWN_DOORBELL 2
49 #define COMMAND_CONFIGURE_MW 3
50 #define COMMAND_TEARDOWN_MW 4
51 #define COMMAND_LINK_UP 5
52 #define COMMAND_LINK_DOWN 6
53
54 #define COMMAND_STATUS_OK 1
55 #define COMMAND_STATUS_ERROR 2
56
57 #define LINK_STATUS_UP BIT(0)
58
59 #define SPAD_COUNT 64
60 #define DB_COUNT 4
61 #define NTB_MW_OFFSET 2
62 #define DB_COUNT_MASK GENMASK(15, 0)
63 #define MSIX_ENABLE BIT(16)
64 #define MAX_DB_COUNT 32
65 #define MAX_MW 4
66
67 enum epf_ntb_bar {
68 BAR_CONFIG,
69 BAR_PEER_SPAD,
70 BAR_DB_MW1,
71 BAR_MW2,
72 BAR_MW3,
73 BAR_MW4,
74 };
75
76 struct epf_ntb {
77 u32 num_mws;
78 u32 db_count;
79 u32 spad_count;
80 struct pci_epf *epf;
81 u64 mws_size[MAX_MW];
82 struct config_group group;
83 struct epf_ntb_epc *epc[2];
84 };
85
86 #define to_epf_ntb(epf_group) container_of((epf_group), struct epf_ntb, group)
87
88 struct epf_ntb_epc {
89 u8 func_no;
90 u8 vfunc_no;
91 bool linkup;
92 bool is_msix;
93 int msix_bar;
94 u32 spad_size;
95 struct pci_epc *epc;
96 struct epf_ntb *epf_ntb;
97 void __iomem *mw_addr[6];
98 size_t msix_table_offset;
99 struct epf_ntb_ctrl *reg;
100 struct pci_epf_bar *epf_bar;
101 enum pci_barno epf_ntb_bar[6];
102 struct delayed_work cmd_handler;
103 enum pci_epc_interface_type type;
104 const struct pci_epc_features *epc_features;
105 };
106
107 struct epf_ntb_ctrl {
108 u32 command;
109 u32 argument;
110 u16 command_status;
111 u16 link_status;
112 u32 topology;
113 u64 addr;
114 u64 size;
115 u32 num_mws;
116 u32 mw1_offset;
117 u32 spad_offset;
118 u32 spad_count;
119 u32 db_entry_size;
120 u32 db_data[MAX_DB_COUNT];
121 u32 db_offset[MAX_DB_COUNT];
122 } __packed;
123
124 static struct pci_epf_header epf_ntb_header = {
125 .vendorid = PCI_ANY_ID,
126 .deviceid = PCI_ANY_ID,
127 .baseclass_code = PCI_BASE_CLASS_MEMORY,
128 .interrupt_pin = PCI_INTERRUPT_INTA,
129 };
130
131 /**
132 * epf_ntb_link_up() - Raise link_up interrupt to both the hosts
133 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
134 * @link_up: true or false indicating Link is UP or Down
135 *
136 * Once NTB function in HOST1 and the NTB function in HOST2 invoke
137 * ntb_link_enable(), this NTB function driver will trigger a link event to
138 * the NTB client in both the hosts.
139 */
epf_ntb_link_up(struct epf_ntb * ntb,bool link_up)140 static int epf_ntb_link_up(struct epf_ntb *ntb, bool link_up)
141 {
142 enum pci_epc_interface_type type;
143 struct epf_ntb_epc *ntb_epc;
144 struct epf_ntb_ctrl *ctrl;
145 unsigned int irq_type;
146 struct pci_epc *epc;
147 u8 func_no, vfunc_no;
148 bool is_msix;
149 int ret;
150
151 for (type = PRIMARY_INTERFACE; type <= SECONDARY_INTERFACE; type++) {
152 ntb_epc = ntb->epc[type];
153 epc = ntb_epc->epc;
154 func_no = ntb_epc->func_no;
155 vfunc_no = ntb_epc->vfunc_no;
156 is_msix = ntb_epc->is_msix;
157 ctrl = ntb_epc->reg;
158 if (link_up)
159 ctrl->link_status |= LINK_STATUS_UP;
160 else
161 ctrl->link_status &= ~LINK_STATUS_UP;
162 irq_type = is_msix ? PCI_IRQ_MSIX : PCI_IRQ_MSI;
163 ret = pci_epc_raise_irq(epc, func_no, vfunc_no, irq_type, 1);
164 if (ret) {
165 dev_err(&epc->dev,
166 "%s intf: Failed to raise Link Up IRQ\n",
167 pci_epc_interface_string(type));
168 return ret;
169 }
170 }
171
172 return 0;
173 }
174
175 /**
176 * epf_ntb_configure_mw() - Configure the Outbound Address Space for one host
177 * to access the memory window of other host
178 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
179 * @type: PRIMARY interface or SECONDARY interface
180 * @mw: Index of the memory window (either 0, 1, 2 or 3)
181 *
182 * +-----------------+ +---->+----------------+-----------+-----------------+
183 * | BAR0 | | | Doorbell 1 +-----------> MSI|X ADDRESS 1 |
184 * +-----------------+ | +----------------+ +-----------------+
185 * | BAR1 | | | Doorbell 2 +---------+ | |
186 * +-----------------+----+ +----------------+ | | |
187 * | BAR2 | | Doorbell 3 +-------+ | +-----------------+
188 * +-----------------+----+ +----------------+ | +-> MSI|X ADDRESS 2 |
189 * | BAR3 | | | Doorbell 4 +-----+ | +-----------------+
190 * +-----------------+ | |----------------+ | | | |
191 * | BAR4 | | | | | | +-----------------+
192 * +-----------------+ | | MW1 +---+ | +-->+ MSI|X ADDRESS 3||
193 * | BAR5 | | | | | | +-----------------+
194 * +-----------------+ +---->-----------------+ | | | |
195 * EP CONTROLLER 1 | | | | +-----------------+
196 * | | | +---->+ MSI|X ADDRESS 4 |
197 * +----------------+ | +-----------------+
198 * (A) EP CONTROLLER 2 | | |
199 * (OB SPACE) | | |
200 * +-------> MW1 |
201 * | |
202 * | |
203 * (B) +-----------------+
204 * | |
205 * | |
206 * | |
207 * | |
208 * | |
209 * +-----------------+
210 * PCI Address Space
211 * (Managed by HOST2)
212 *
213 * This function performs stage (B) in the above diagram (see MW1) i.e., map OB
214 * address space of memory window to PCI address space.
215 *
216 * This operation requires 3 parameters
217 * 1) Address in the outbound address space
218 * 2) Address in the PCI Address space
219 * 3) Size of the address region to be mapped
220 *
221 * The address in the outbound address space (for MW1, MW2, MW3 and MW4) is
222 * stored in epf_bar corresponding to BAR_DB_MW1 for MW1 and BAR_MW2, BAR_MW3
223 * BAR_MW4 for rest of the BARs of epf_ntb_epc that is connected to HOST1. This
224 * is populated in epf_ntb_alloc_peer_mem() in this driver.
225 *
226 * The address and size of the PCI address region that has to be mapped would
227 * be provided by HOST2 in ctrl->addr and ctrl->size of epf_ntb_epc that is
228 * connected to HOST2.
229 *
230 * Please note Memory window1 (MW1) and Doorbell registers together will be
231 * mapped to a single BAR (BAR2) above for 32-bit BARs. The exact BAR that's
232 * used for Memory window (MW) can be obtained from epf_ntb_bar[BAR_DB_MW1],
233 * epf_ntb_bar[BAR_MW2], epf_ntb_bar[BAR_MW2], epf_ntb_bar[BAR_MW2].
234 */
epf_ntb_configure_mw(struct epf_ntb * ntb,enum pci_epc_interface_type type,u32 mw)235 static int epf_ntb_configure_mw(struct epf_ntb *ntb,
236 enum pci_epc_interface_type type, u32 mw)
237 {
238 struct epf_ntb_epc *peer_ntb_epc, *ntb_epc;
239 struct pci_epf_bar *peer_epf_bar;
240 enum pci_barno peer_barno;
241 struct epf_ntb_ctrl *ctrl;
242 phys_addr_t phys_addr;
243 u8 func_no, vfunc_no;
244 struct pci_epc *epc;
245 u64 addr, size;
246 int ret = 0;
247
248 ntb_epc = ntb->epc[type];
249 epc = ntb_epc->epc;
250
251 peer_ntb_epc = ntb->epc[!type];
252 peer_barno = peer_ntb_epc->epf_ntb_bar[mw + NTB_MW_OFFSET];
253 peer_epf_bar = &peer_ntb_epc->epf_bar[peer_barno];
254
255 phys_addr = peer_epf_bar->phys_addr;
256 ctrl = ntb_epc->reg;
257 addr = ctrl->addr;
258 size = ctrl->size;
259 if (mw + NTB_MW_OFFSET == BAR_DB_MW1)
260 phys_addr += ctrl->mw1_offset;
261
262 if (size > ntb->mws_size[mw]) {
263 dev_err(&epc->dev,
264 "%s intf: MW: %d Req Sz:%llxx > Supported Sz:%llx\n",
265 pci_epc_interface_string(type), mw, size,
266 ntb->mws_size[mw]);
267 ret = -EINVAL;
268 goto err_invalid_size;
269 }
270
271 func_no = ntb_epc->func_no;
272 vfunc_no = ntb_epc->vfunc_no;
273
274 ret = pci_epc_map_addr(epc, func_no, vfunc_no, phys_addr, addr, size);
275 if (ret)
276 dev_err(&epc->dev,
277 "%s intf: Failed to map memory window %d address\n",
278 pci_epc_interface_string(type), mw);
279
280 err_invalid_size:
281
282 return ret;
283 }
284
285 /**
286 * epf_ntb_teardown_mw() - Teardown the configured OB ATU
287 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
288 * @type: PRIMARY interface or SECONDARY interface
289 * @mw: Index of the memory window (either 0, 1, 2 or 3)
290 *
291 * Teardown the configured OB ATU configured in epf_ntb_configure_mw() using
292 * pci_epc_unmap_addr()
293 */
epf_ntb_teardown_mw(struct epf_ntb * ntb,enum pci_epc_interface_type type,u32 mw)294 static void epf_ntb_teardown_mw(struct epf_ntb *ntb,
295 enum pci_epc_interface_type type, u32 mw)
296 {
297 struct epf_ntb_epc *peer_ntb_epc, *ntb_epc;
298 struct pci_epf_bar *peer_epf_bar;
299 enum pci_barno peer_barno;
300 struct epf_ntb_ctrl *ctrl;
301 phys_addr_t phys_addr;
302 u8 func_no, vfunc_no;
303 struct pci_epc *epc;
304
305 ntb_epc = ntb->epc[type];
306 epc = ntb_epc->epc;
307
308 peer_ntb_epc = ntb->epc[!type];
309 peer_barno = peer_ntb_epc->epf_ntb_bar[mw + NTB_MW_OFFSET];
310 peer_epf_bar = &peer_ntb_epc->epf_bar[peer_barno];
311
312 phys_addr = peer_epf_bar->phys_addr;
313 ctrl = ntb_epc->reg;
314 if (mw + NTB_MW_OFFSET == BAR_DB_MW1)
315 phys_addr += ctrl->mw1_offset;
316 func_no = ntb_epc->func_no;
317 vfunc_no = ntb_epc->vfunc_no;
318
319 pci_epc_unmap_addr(epc, func_no, vfunc_no, phys_addr);
320 }
321
322 /**
323 * epf_ntb_configure_msi() - Map OB address space to MSI address
324 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
325 * @type: PRIMARY interface or SECONDARY interface
326 * @db_count: Number of doorbell interrupts to map
327 *
328 *+-----------------+ +----->+----------------+-----------+-----------------+
329 *| BAR0 | | | Doorbell 1 +---+-------> MSI ADDRESS |
330 *+-----------------+ | +----------------+ | +-----------------+
331 *| BAR1 | | | Doorbell 2 +---+ | |
332 *+-----------------+----+ +----------------+ | | |
333 *| BAR2 | | Doorbell 3 +---+ | |
334 *+-----------------+----+ +----------------+ | | |
335 *| BAR3 | | | Doorbell 4 +---+ | |
336 *+-----------------+ | |----------------+ | |
337 *| BAR4 | | | | | |
338 *+-----------------+ | | MW1 | | |
339 *| BAR5 | | | | | |
340 *+-----------------+ +----->-----------------+ | |
341 * EP CONTROLLER 1 | | | |
342 * | | | |
343 * +----------------+ +-----------------+
344 * (A) EP CONTROLLER 2 | |
345 * (OB SPACE) | |
346 * | MW1 |
347 * | |
348 * | |
349 * (B) +-----------------+
350 * | |
351 * | |
352 * | |
353 * | |
354 * | |
355 * +-----------------+
356 * PCI Address Space
357 * (Managed by HOST2)
358 *
359 *
360 * This function performs stage (B) in the above diagram (see Doorbell 1,
361 * Doorbell 2, Doorbell 3, Doorbell 4) i.e map OB address space corresponding to
362 * doorbell to MSI address in PCI address space.
363 *
364 * This operation requires 3 parameters
365 * 1) Address reserved for doorbell in the outbound address space
366 * 2) MSI-X address in the PCIe Address space
367 * 3) Number of MSI-X interrupts that has to be configured
368 *
369 * The address in the outbound address space (for the Doorbell) is stored in
370 * epf_bar corresponding to BAR_DB_MW1 of epf_ntb_epc that is connected to
371 * HOST1. This is populated in epf_ntb_alloc_peer_mem() in this driver along
372 * with address for MW1.
373 *
374 * pci_epc_map_msi_irq() takes the MSI address from MSI capability register
375 * and maps the OB address (obtained in epf_ntb_alloc_peer_mem()) to the MSI
376 * address.
377 *
378 * epf_ntb_configure_msi() also stores the MSI data to raise each interrupt
379 * in db_data of the peer's control region. This helps the peer to raise
380 * doorbell of the other host by writing db_data to the BAR corresponding to
381 * BAR_DB_MW1.
382 */
epf_ntb_configure_msi(struct epf_ntb * ntb,enum pci_epc_interface_type type,u16 db_count)383 static int epf_ntb_configure_msi(struct epf_ntb *ntb,
384 enum pci_epc_interface_type type, u16 db_count)
385 {
386 struct epf_ntb_epc *peer_ntb_epc, *ntb_epc;
387 u32 db_entry_size, db_data, db_offset;
388 struct pci_epf_bar *peer_epf_bar;
389 struct epf_ntb_ctrl *peer_ctrl;
390 enum pci_barno peer_barno;
391 phys_addr_t phys_addr;
392 u8 func_no, vfunc_no;
393 struct pci_epc *epc;
394 int ret, i;
395
396 ntb_epc = ntb->epc[type];
397 epc = ntb_epc->epc;
398
399 peer_ntb_epc = ntb->epc[!type];
400 peer_barno = peer_ntb_epc->epf_ntb_bar[BAR_DB_MW1];
401 peer_epf_bar = &peer_ntb_epc->epf_bar[peer_barno];
402 peer_ctrl = peer_ntb_epc->reg;
403 db_entry_size = peer_ctrl->db_entry_size;
404
405 phys_addr = peer_epf_bar->phys_addr;
406 func_no = ntb_epc->func_no;
407 vfunc_no = ntb_epc->vfunc_no;
408
409 ret = pci_epc_map_msi_irq(epc, func_no, vfunc_no, phys_addr, db_count,
410 db_entry_size, &db_data, &db_offset);
411 if (ret) {
412 dev_err(&epc->dev, "%s intf: Failed to map MSI IRQ\n",
413 pci_epc_interface_string(type));
414 return ret;
415 }
416
417 for (i = 0; i < db_count; i++) {
418 peer_ctrl->db_data[i] = db_data | i;
419 peer_ctrl->db_offset[i] = db_offset;
420 }
421
422 return 0;
423 }
424
425 /**
426 * epf_ntb_configure_msix() - Map OB address space to MSI-X address
427 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
428 * @type: PRIMARY interface or SECONDARY interface
429 * @db_count: Number of doorbell interrupts to map
430 *
431 *+-----------------+ +----->+----------------+-----------+-----------------+
432 *| BAR0 | | | Doorbell 1 +-----------> MSI-X ADDRESS 1 |
433 *+-----------------+ | +----------------+ +-----------------+
434 *| BAR1 | | | Doorbell 2 +---------+ | |
435 *+-----------------+----+ +----------------+ | | |
436 *| BAR2 | | Doorbell 3 +-------+ | +-----------------+
437 *+-----------------+----+ +----------------+ | +-> MSI-X ADDRESS 2 |
438 *| BAR3 | | | Doorbell 4 +-----+ | +-----------------+
439 *+-----------------+ | |----------------+ | | | |
440 *| BAR4 | | | | | | +-----------------+
441 *+-----------------+ | | MW1 + | +-->+ MSI-X ADDRESS 3||
442 *| BAR5 | | | | | +-----------------+
443 *+-----------------+ +----->-----------------+ | | |
444 * EP CONTROLLER 1 | | | +-----------------+
445 * | | +---->+ MSI-X ADDRESS 4 |
446 * +----------------+ +-----------------+
447 * (A) EP CONTROLLER 2 | |
448 * (OB SPACE) | |
449 * | MW1 |
450 * | |
451 * | |
452 * (B) +-----------------+
453 * | |
454 * | |
455 * | |
456 * | |
457 * | |
458 * +-----------------+
459 * PCI Address Space
460 * (Managed by HOST2)
461 *
462 * This function performs stage (B) in the above diagram (see Doorbell 1,
463 * Doorbell 2, Doorbell 3, Doorbell 4) i.e map OB address space corresponding to
464 * doorbell to MSI-X address in PCI address space.
465 *
466 * This operation requires 3 parameters
467 * 1) Address reserved for doorbell in the outbound address space
468 * 2) MSI-X address in the PCIe Address space
469 * 3) Number of MSI-X interrupts that has to be configured
470 *
471 * The address in the outbound address space (for the Doorbell) is stored in
472 * epf_bar corresponding to BAR_DB_MW1 of epf_ntb_epc that is connected to
473 * HOST1. This is populated in epf_ntb_alloc_peer_mem() in this driver along
474 * with address for MW1.
475 *
476 * The MSI-X address is in the MSI-X table of EP CONTROLLER 2 and
477 * the count of doorbell is in ctrl->argument of epf_ntb_epc that is connected
478 * to HOST2. MSI-X table is stored memory mapped to ntb_epc->msix_bar and the
479 * offset is in ntb_epc->msix_table_offset. From this epf_ntb_configure_msix()
480 * gets the MSI-X address and data.
481 *
482 * epf_ntb_configure_msix() also stores the MSI-X data to raise each interrupt
483 * in db_data of the peer's control region. This helps the peer to raise
484 * doorbell of the other host by writing db_data to the BAR corresponding to
485 * BAR_DB_MW1.
486 */
epf_ntb_configure_msix(struct epf_ntb * ntb,enum pci_epc_interface_type type,u16 db_count)487 static int epf_ntb_configure_msix(struct epf_ntb *ntb,
488 enum pci_epc_interface_type type,
489 u16 db_count)
490 {
491 const struct pci_epc_features *epc_features;
492 struct epf_ntb_epc *peer_ntb_epc, *ntb_epc;
493 struct pci_epf_bar *peer_epf_bar, *epf_bar;
494 struct pci_epf_msix_tbl *msix_tbl;
495 struct epf_ntb_ctrl *peer_ctrl;
496 u32 db_entry_size, msg_data;
497 enum pci_barno peer_barno;
498 phys_addr_t phys_addr;
499 u8 func_no, vfunc_no;
500 struct pci_epc *epc;
501 size_t align;
502 u64 msg_addr;
503 int ret, i;
504
505 ntb_epc = ntb->epc[type];
506 epc = ntb_epc->epc;
507
508 epf_bar = &ntb_epc->epf_bar[ntb_epc->msix_bar];
509 msix_tbl = epf_bar->addr + ntb_epc->msix_table_offset;
510
511 peer_ntb_epc = ntb->epc[!type];
512 peer_barno = peer_ntb_epc->epf_ntb_bar[BAR_DB_MW1];
513 peer_epf_bar = &peer_ntb_epc->epf_bar[peer_barno];
514 phys_addr = peer_epf_bar->phys_addr;
515 peer_ctrl = peer_ntb_epc->reg;
516 epc_features = ntb_epc->epc_features;
517 align = epc_features->align;
518
519 func_no = ntb_epc->func_no;
520 vfunc_no = ntb_epc->vfunc_no;
521 db_entry_size = peer_ctrl->db_entry_size;
522
523 for (i = 0; i < db_count; i++) {
524 msg_addr = ALIGN_DOWN(msix_tbl[i].msg_addr, align);
525 msg_data = msix_tbl[i].msg_data;
526 ret = pci_epc_map_addr(epc, func_no, vfunc_no, phys_addr, msg_addr,
527 db_entry_size);
528 if (ret) {
529 dev_err(&epc->dev,
530 "%s intf: Failed to configure MSI-X IRQ\n",
531 pci_epc_interface_string(type));
532 return ret;
533 }
534 phys_addr = phys_addr + db_entry_size;
535 peer_ctrl->db_data[i] = msg_data;
536 peer_ctrl->db_offset[i] = msix_tbl[i].msg_addr & (align - 1);
537 }
538 ntb_epc->is_msix = true;
539
540 return 0;
541 }
542
543 /**
544 * epf_ntb_configure_db() - Configure the Outbound Address Space for one host
545 * to ring the doorbell of other host
546 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
547 * @type: PRIMARY interface or SECONDARY interface
548 * @db_count: Count of the number of doorbells that has to be configured
549 * @msix: Indicates whether MSI-X or MSI should be used
550 *
551 * Invokes epf_ntb_configure_msix() or epf_ntb_configure_msi() required for
552 * one HOST to ring the doorbell of other HOST.
553 */
epf_ntb_configure_db(struct epf_ntb * ntb,enum pci_epc_interface_type type,u16 db_count,bool msix)554 static int epf_ntb_configure_db(struct epf_ntb *ntb,
555 enum pci_epc_interface_type type,
556 u16 db_count, bool msix)
557 {
558 struct epf_ntb_epc *ntb_epc;
559 struct pci_epc *epc;
560 int ret;
561
562 if (db_count > MAX_DB_COUNT)
563 return -EINVAL;
564
565 ntb_epc = ntb->epc[type];
566 epc = ntb_epc->epc;
567
568 if (msix)
569 ret = epf_ntb_configure_msix(ntb, type, db_count);
570 else
571 ret = epf_ntb_configure_msi(ntb, type, db_count);
572
573 if (ret)
574 dev_err(&epc->dev, "%s intf: Failed to configure DB\n",
575 pci_epc_interface_string(type));
576
577 return ret;
578 }
579
580 /**
581 * epf_ntb_teardown_db() - Unmap address in OB address space to MSI/MSI-X
582 * address
583 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
584 * @type: PRIMARY interface or SECONDARY interface
585 *
586 * Invoke pci_epc_unmap_addr() to unmap OB address to MSI/MSI-X address.
587 */
588 static void
epf_ntb_teardown_db(struct epf_ntb * ntb,enum pci_epc_interface_type type)589 epf_ntb_teardown_db(struct epf_ntb *ntb, enum pci_epc_interface_type type)
590 {
591 struct epf_ntb_epc *peer_ntb_epc, *ntb_epc;
592 struct pci_epf_bar *peer_epf_bar;
593 enum pci_barno peer_barno;
594 phys_addr_t phys_addr;
595 u8 func_no, vfunc_no;
596 struct pci_epc *epc;
597
598 ntb_epc = ntb->epc[type];
599 epc = ntb_epc->epc;
600
601 peer_ntb_epc = ntb->epc[!type];
602 peer_barno = peer_ntb_epc->epf_ntb_bar[BAR_DB_MW1];
603 peer_epf_bar = &peer_ntb_epc->epf_bar[peer_barno];
604 phys_addr = peer_epf_bar->phys_addr;
605 func_no = ntb_epc->func_no;
606 vfunc_no = ntb_epc->vfunc_no;
607
608 pci_epc_unmap_addr(epc, func_no, vfunc_no, phys_addr);
609 }
610
611 /**
612 * epf_ntb_cmd_handler() - Handle commands provided by the NTB Host
613 * @work: work_struct for the two epf_ntb_epc (PRIMARY and SECONDARY)
614 *
615 * Workqueue function that gets invoked for the two epf_ntb_epc
616 * periodically (once every 5ms) to see if it has received any commands
617 * from NTB host. The host can send commands to configure doorbell or
618 * configure memory window or to update link status.
619 */
epf_ntb_cmd_handler(struct work_struct * work)620 static void epf_ntb_cmd_handler(struct work_struct *work)
621 {
622 enum pci_epc_interface_type type;
623 struct epf_ntb_epc *ntb_epc;
624 struct epf_ntb_ctrl *ctrl;
625 u32 command, argument;
626 struct epf_ntb *ntb;
627 struct device *dev;
628 u16 db_count;
629 bool is_msix;
630 int ret;
631
632 ntb_epc = container_of(work, struct epf_ntb_epc, cmd_handler.work);
633 ctrl = ntb_epc->reg;
634 command = ctrl->command;
635 if (!command)
636 goto reset_handler;
637 argument = ctrl->argument;
638
639 ctrl->command = 0;
640 ctrl->argument = 0;
641
642 ctrl = ntb_epc->reg;
643 type = ntb_epc->type;
644 ntb = ntb_epc->epf_ntb;
645 dev = &ntb->epf->dev;
646
647 switch (command) {
648 case COMMAND_CONFIGURE_DOORBELL:
649 db_count = argument & DB_COUNT_MASK;
650 is_msix = argument & MSIX_ENABLE;
651 ret = epf_ntb_configure_db(ntb, type, db_count, is_msix);
652 if (ret < 0)
653 ctrl->command_status = COMMAND_STATUS_ERROR;
654 else
655 ctrl->command_status = COMMAND_STATUS_OK;
656 break;
657 case COMMAND_TEARDOWN_DOORBELL:
658 epf_ntb_teardown_db(ntb, type);
659 ctrl->command_status = COMMAND_STATUS_OK;
660 break;
661 case COMMAND_CONFIGURE_MW:
662 ret = epf_ntb_configure_mw(ntb, type, argument);
663 if (ret < 0)
664 ctrl->command_status = COMMAND_STATUS_ERROR;
665 else
666 ctrl->command_status = COMMAND_STATUS_OK;
667 break;
668 case COMMAND_TEARDOWN_MW:
669 epf_ntb_teardown_mw(ntb, type, argument);
670 ctrl->command_status = COMMAND_STATUS_OK;
671 break;
672 case COMMAND_LINK_UP:
673 ntb_epc->linkup = true;
674 if (ntb->epc[PRIMARY_INTERFACE]->linkup &&
675 ntb->epc[SECONDARY_INTERFACE]->linkup) {
676 ret = epf_ntb_link_up(ntb, true);
677 if (ret < 0)
678 ctrl->command_status = COMMAND_STATUS_ERROR;
679 else
680 ctrl->command_status = COMMAND_STATUS_OK;
681 goto reset_handler;
682 }
683 ctrl->command_status = COMMAND_STATUS_OK;
684 break;
685 case COMMAND_LINK_DOWN:
686 ntb_epc->linkup = false;
687 ret = epf_ntb_link_up(ntb, false);
688 if (ret < 0)
689 ctrl->command_status = COMMAND_STATUS_ERROR;
690 else
691 ctrl->command_status = COMMAND_STATUS_OK;
692 break;
693 default:
694 dev_err(dev, "%s intf UNKNOWN command: %d\n",
695 pci_epc_interface_string(type), command);
696 break;
697 }
698
699 reset_handler:
700 queue_delayed_work(kpcintb_workqueue, &ntb_epc->cmd_handler,
701 msecs_to_jiffies(5));
702 }
703
704 /**
705 * epf_ntb_peer_spad_bar_clear() - Clear Peer Scratchpad BAR
706 * @ntb_epc: EPC associated with one of the HOST which holds peer's outbound
707 * address.
708 *
709 *+-----------------+------->+------------------+ +-----------------+
710 *| BAR0 | | CONFIG REGION | | BAR0 |
711 *+-----------------+----+ +------------------+<-------+-----------------+
712 *| BAR1 | | |SCRATCHPAD REGION | | BAR1 |
713 *+-----------------+ +-->+------------------+<-------+-----------------+
714 *| BAR2 | Local Memory | BAR2 |
715 *+-----------------+ +-----------------+
716 *| BAR3 | | BAR3 |
717 *+-----------------+ +-----------------+
718 *| BAR4 | | BAR4 |
719 *+-----------------+ +-----------------+
720 *| BAR5 | | BAR5 |
721 *+-----------------+ +-----------------+
722 * EP CONTROLLER 1 EP CONTROLLER 2
723 *
724 * Clear BAR1 of EP CONTROLLER 2 which contains the HOST2's peer scratchpad
725 * region. While BAR1 is the default peer scratchpad BAR, an NTB could have
726 * other BARs for peer scratchpad (because of 64-bit BARs or reserved BARs).
727 * This function can get the exact BAR used for peer scratchpad from
728 * epf_ntb_bar[BAR_PEER_SPAD].
729 *
730 * Since HOST2's peer scratchpad is also HOST1's self scratchpad, this function
731 * gets the address of peer scratchpad from
732 * peer_ntb_epc->epf_ntb_bar[BAR_CONFIG].
733 */
epf_ntb_peer_spad_bar_clear(struct epf_ntb_epc * ntb_epc)734 static void epf_ntb_peer_spad_bar_clear(struct epf_ntb_epc *ntb_epc)
735 {
736 struct pci_epf_bar *epf_bar;
737 enum pci_barno barno;
738 u8 func_no, vfunc_no;
739 struct pci_epc *epc;
740
741 epc = ntb_epc->epc;
742 func_no = ntb_epc->func_no;
743 vfunc_no = ntb_epc->vfunc_no;
744 barno = ntb_epc->epf_ntb_bar[BAR_PEER_SPAD];
745 epf_bar = &ntb_epc->epf_bar[barno];
746 pci_epc_clear_bar(epc, func_no, vfunc_no, epf_bar);
747 }
748
749 /**
750 * epf_ntb_peer_spad_bar_set() - Set peer scratchpad BAR
751 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
752 * @type: PRIMARY interface or SECONDARY interface
753 *
754 *+-----------------+------->+------------------+ +-----------------+
755 *| BAR0 | | CONFIG REGION | | BAR0 |
756 *+-----------------+----+ +------------------+<-------+-----------------+
757 *| BAR1 | | |SCRATCHPAD REGION | | BAR1 |
758 *+-----------------+ +-->+------------------+<-------+-----------------+
759 *| BAR2 | Local Memory | BAR2 |
760 *+-----------------+ +-----------------+
761 *| BAR3 | | BAR3 |
762 *+-----------------+ +-----------------+
763 *| BAR4 | | BAR4 |
764 *+-----------------+ +-----------------+
765 *| BAR5 | | BAR5 |
766 *+-----------------+ +-----------------+
767 * EP CONTROLLER 1 EP CONTROLLER 2
768 *
769 * Set BAR1 of EP CONTROLLER 2 which contains the HOST2's peer scratchpad
770 * region. While BAR1 is the default peer scratchpad BAR, an NTB could have
771 * other BARs for peer scratchpad (because of 64-bit BARs or reserved BARs).
772 * This function can get the exact BAR used for peer scratchpad from
773 * epf_ntb_bar[BAR_PEER_SPAD].
774 *
775 * Since HOST2's peer scratchpad is also HOST1's self scratchpad, this function
776 * gets the address of peer scratchpad from
777 * peer_ntb_epc->epf_ntb_bar[BAR_CONFIG].
778 */
epf_ntb_peer_spad_bar_set(struct epf_ntb * ntb,enum pci_epc_interface_type type)779 static int epf_ntb_peer_spad_bar_set(struct epf_ntb *ntb,
780 enum pci_epc_interface_type type)
781 {
782 struct epf_ntb_epc *peer_ntb_epc, *ntb_epc;
783 struct pci_epf_bar *peer_epf_bar, *epf_bar;
784 enum pci_barno peer_barno, barno;
785 u32 peer_spad_offset;
786 u8 func_no, vfunc_no;
787 struct pci_epc *epc;
788 struct device *dev;
789 int ret;
790
791 dev = &ntb->epf->dev;
792
793 peer_ntb_epc = ntb->epc[!type];
794 peer_barno = peer_ntb_epc->epf_ntb_bar[BAR_CONFIG];
795 peer_epf_bar = &peer_ntb_epc->epf_bar[peer_barno];
796
797 ntb_epc = ntb->epc[type];
798 barno = ntb_epc->epf_ntb_bar[BAR_PEER_SPAD];
799 epf_bar = &ntb_epc->epf_bar[barno];
800 func_no = ntb_epc->func_no;
801 vfunc_no = ntb_epc->vfunc_no;
802 epc = ntb_epc->epc;
803
804 peer_spad_offset = peer_ntb_epc->reg->spad_offset;
805 epf_bar->phys_addr = peer_epf_bar->phys_addr + peer_spad_offset;
806 epf_bar->size = peer_ntb_epc->spad_size;
807 epf_bar->barno = barno;
808 epf_bar->flags = PCI_BASE_ADDRESS_MEM_TYPE_32;
809
810 ret = pci_epc_set_bar(epc, func_no, vfunc_no, epf_bar);
811 if (ret) {
812 dev_err(dev, "%s intf: peer SPAD BAR set failed\n",
813 pci_epc_interface_string(type));
814 return ret;
815 }
816
817 return 0;
818 }
819
820 /**
821 * epf_ntb_config_sspad_bar_clear() - Clear Config + Self scratchpad BAR
822 * @ntb_epc: EPC associated with one of the HOST which holds peer's outbound
823 * address.
824 *
825 * +-----------------+------->+------------------+ +-----------------+
826 * | BAR0 | | CONFIG REGION | | BAR0 |
827 * +-----------------+----+ +------------------+<-------+-----------------+
828 * | BAR1 | | |SCRATCHPAD REGION | | BAR1 |
829 * +-----------------+ +-->+------------------+<-------+-----------------+
830 * | BAR2 | Local Memory | BAR2 |
831 * +-----------------+ +-----------------+
832 * | BAR3 | | BAR3 |
833 * +-----------------+ +-----------------+
834 * | BAR4 | | BAR4 |
835 * +-----------------+ +-----------------+
836 * | BAR5 | | BAR5 |
837 * +-----------------+ +-----------------+
838 * EP CONTROLLER 1 EP CONTROLLER 2
839 *
840 * Clear BAR0 of EP CONTROLLER 1 which contains the HOST1's config and
841 * self scratchpad region (removes inbound ATU configuration). While BAR0 is
842 * the default self scratchpad BAR, an NTB could have other BARs for self
843 * scratchpad (because of reserved BARs). This function can get the exact BAR
844 * used for self scratchpad from epf_ntb_bar[BAR_CONFIG].
845 *
846 * Please note the self scratchpad region and config region is combined to
847 * a single region and mapped using the same BAR. Also note HOST2's peer
848 * scratchpad is HOST1's self scratchpad.
849 */
epf_ntb_config_sspad_bar_clear(struct epf_ntb_epc * ntb_epc)850 static void epf_ntb_config_sspad_bar_clear(struct epf_ntb_epc *ntb_epc)
851 {
852 struct pci_epf_bar *epf_bar;
853 enum pci_barno barno;
854 u8 func_no, vfunc_no;
855 struct pci_epc *epc;
856
857 epc = ntb_epc->epc;
858 func_no = ntb_epc->func_no;
859 vfunc_no = ntb_epc->vfunc_no;
860 barno = ntb_epc->epf_ntb_bar[BAR_CONFIG];
861 epf_bar = &ntb_epc->epf_bar[barno];
862 pci_epc_clear_bar(epc, func_no, vfunc_no, epf_bar);
863 }
864
865 /**
866 * epf_ntb_config_sspad_bar_set() - Set Config + Self scratchpad BAR
867 * @ntb_epc: EPC associated with one of the HOST which holds peer's outbound
868 * address.
869 *
870 * +-----------------+------->+------------------+ +-----------------+
871 * | BAR0 | | CONFIG REGION | | BAR0 |
872 * +-----------------+----+ +------------------+<-------+-----------------+
873 * | BAR1 | | |SCRATCHPAD REGION | | BAR1 |
874 * +-----------------+ +-->+------------------+<-------+-----------------+
875 * | BAR2 | Local Memory | BAR2 |
876 * +-----------------+ +-----------------+
877 * | BAR3 | | BAR3 |
878 * +-----------------+ +-----------------+
879 * | BAR4 | | BAR4 |
880 * +-----------------+ +-----------------+
881 * | BAR5 | | BAR5 |
882 * +-----------------+ +-----------------+
883 * EP CONTROLLER 1 EP CONTROLLER 2
884 *
885 * Map BAR0 of EP CONTROLLER 1 which contains the HOST1's config and
886 * self scratchpad region. While BAR0 is the default self scratchpad BAR, an
887 * NTB could have other BARs for self scratchpad (because of reserved BARs).
888 * This function can get the exact BAR used for self scratchpad from
889 * epf_ntb_bar[BAR_CONFIG].
890 *
891 * Please note the self scratchpad region and config region is combined to
892 * a single region and mapped using the same BAR. Also note HOST2's peer
893 * scratchpad is HOST1's self scratchpad.
894 */
epf_ntb_config_sspad_bar_set(struct epf_ntb_epc * ntb_epc)895 static int epf_ntb_config_sspad_bar_set(struct epf_ntb_epc *ntb_epc)
896 {
897 struct pci_epf_bar *epf_bar;
898 enum pci_barno barno;
899 u8 func_no, vfunc_no;
900 struct epf_ntb *ntb;
901 struct pci_epc *epc;
902 struct device *dev;
903 int ret;
904
905 ntb = ntb_epc->epf_ntb;
906 dev = &ntb->epf->dev;
907
908 epc = ntb_epc->epc;
909 func_no = ntb_epc->func_no;
910 vfunc_no = ntb_epc->vfunc_no;
911 barno = ntb_epc->epf_ntb_bar[BAR_CONFIG];
912 epf_bar = &ntb_epc->epf_bar[barno];
913
914 ret = pci_epc_set_bar(epc, func_no, vfunc_no, epf_bar);
915 if (ret) {
916 dev_err(dev, "%s inft: Config/Status/SPAD BAR set failed\n",
917 pci_epc_interface_string(ntb_epc->type));
918 return ret;
919 }
920
921 return 0;
922 }
923
924 /**
925 * epf_ntb_config_spad_bar_free() - Free the physical memory associated with
926 * config + scratchpad region
927 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
928 *
929 * +-----------------+------->+------------------+ +-----------------+
930 * | BAR0 | | CONFIG REGION | | BAR0 |
931 * +-----------------+----+ +------------------+<-------+-----------------+
932 * | BAR1 | | |SCRATCHPAD REGION | | BAR1 |
933 * +-----------------+ +-->+------------------+<-------+-----------------+
934 * | BAR2 | Local Memory | BAR2 |
935 * +-----------------+ +-----------------+
936 * | BAR3 | | BAR3 |
937 * +-----------------+ +-----------------+
938 * | BAR4 | | BAR4 |
939 * +-----------------+ +-----------------+
940 * | BAR5 | | BAR5 |
941 * +-----------------+ +-----------------+
942 * EP CONTROLLER 1 EP CONTROLLER 2
943 *
944 * Free the Local Memory mentioned in the above diagram. After invoking this
945 * function, any of config + self scratchpad region of HOST1 or peer scratchpad
946 * region of HOST2 should not be accessed.
947 */
epf_ntb_config_spad_bar_free(struct epf_ntb * ntb)948 static void epf_ntb_config_spad_bar_free(struct epf_ntb *ntb)
949 {
950 enum pci_epc_interface_type type;
951 struct epf_ntb_epc *ntb_epc;
952 enum pci_barno barno;
953 struct pci_epf *epf;
954
955 epf = ntb->epf;
956 for (type = PRIMARY_INTERFACE; type <= SECONDARY_INTERFACE; type++) {
957 ntb_epc = ntb->epc[type];
958 barno = ntb_epc->epf_ntb_bar[BAR_CONFIG];
959 if (ntb_epc->reg)
960 pci_epf_free_space(epf, ntb_epc->reg, barno, type);
961 }
962 }
963
964 /**
965 * epf_ntb_config_spad_bar_alloc() - Allocate memory for config + scratchpad
966 * region
967 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
968 * @type: PRIMARY interface or SECONDARY interface
969 *
970 * +-----------------+------->+------------------+ +-----------------+
971 * | BAR0 | | CONFIG REGION | | BAR0 |
972 * +-----------------+----+ +------------------+<-------+-----------------+
973 * | BAR1 | | |SCRATCHPAD REGION | | BAR1 |
974 * +-----------------+ +-->+------------------+<-------+-----------------+
975 * | BAR2 | Local Memory | BAR2 |
976 * +-----------------+ +-----------------+
977 * | BAR3 | | BAR3 |
978 * +-----------------+ +-----------------+
979 * | BAR4 | | BAR4 |
980 * +-----------------+ +-----------------+
981 * | BAR5 | | BAR5 |
982 * +-----------------+ +-----------------+
983 * EP CONTROLLER 1 EP CONTROLLER 2
984 *
985 * Allocate the Local Memory mentioned in the above diagram. The size of
986 * CONFIG REGION is sizeof(struct epf_ntb_ctrl) and size of SCRATCHPAD REGION
987 * is obtained from "spad-count" configfs entry.
988 *
989 * The size of both config region and scratchpad region has to be aligned,
990 * since the scratchpad region will also be mapped as PEER SCRATCHPAD of
991 * other host using a separate BAR.
992 */
epf_ntb_config_spad_bar_alloc(struct epf_ntb * ntb,enum pci_epc_interface_type type)993 static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb,
994 enum pci_epc_interface_type type)
995 {
996 const struct pci_epc_features *peer_epc_features, *epc_features;
997 struct epf_ntb_epc *peer_ntb_epc, *ntb_epc;
998 size_t msix_table_size, pba_size, align;
999 enum pci_barno peer_barno, barno;
1000 struct epf_ntb_ctrl *ctrl;
1001 u32 spad_size, ctrl_size;
1002 u64 size, peer_size;
1003 struct pci_epf *epf;
1004 struct device *dev;
1005 bool msix_capable;
1006 u32 spad_count;
1007 void *base;
1008
1009 epf = ntb->epf;
1010 dev = &epf->dev;
1011 ntb_epc = ntb->epc[type];
1012
1013 epc_features = ntb_epc->epc_features;
1014 barno = ntb_epc->epf_ntb_bar[BAR_CONFIG];
1015 size = epc_features->bar[barno].fixed_size;
1016 align = epc_features->align;
1017
1018 peer_ntb_epc = ntb->epc[!type];
1019 peer_epc_features = peer_ntb_epc->epc_features;
1020 peer_barno = ntb_epc->epf_ntb_bar[BAR_PEER_SPAD];
1021 peer_size = peer_epc_features->bar[peer_barno].fixed_size;
1022
1023 /* Check if epc_features is populated incorrectly */
1024 if ((!IS_ALIGNED(size, align)))
1025 return -EINVAL;
1026
1027 spad_count = ntb->spad_count;
1028
1029 ctrl_size = sizeof(struct epf_ntb_ctrl);
1030 spad_size = spad_count * 4;
1031
1032 msix_capable = epc_features->msix_capable;
1033 if (msix_capable) {
1034 msix_table_size = PCI_MSIX_ENTRY_SIZE * ntb->db_count;
1035 ctrl_size = ALIGN(ctrl_size, 8);
1036 ntb_epc->msix_table_offset = ctrl_size;
1037 ntb_epc->msix_bar = barno;
1038 /* Align to QWORD or 8 Bytes */
1039 pba_size = ALIGN(DIV_ROUND_UP(ntb->db_count, 8), 8);
1040 ctrl_size = ctrl_size + msix_table_size + pba_size;
1041 }
1042
1043 if (!align) {
1044 ctrl_size = roundup_pow_of_two(ctrl_size);
1045 spad_size = roundup_pow_of_two(spad_size);
1046 } else {
1047 ctrl_size = ALIGN(ctrl_size, align);
1048 spad_size = ALIGN(spad_size, align);
1049 }
1050
1051 if (peer_size) {
1052 if (peer_size < spad_size)
1053 spad_count = peer_size / 4;
1054 spad_size = peer_size;
1055 }
1056
1057 /*
1058 * In order to make sure SPAD offset is aligned to its size,
1059 * expand control region size to the size of SPAD if SPAD size
1060 * is greater than control region size.
1061 */
1062 if (spad_size > ctrl_size)
1063 ctrl_size = spad_size;
1064
1065 if (!size)
1066 size = ctrl_size + spad_size;
1067 else if (size < ctrl_size + spad_size)
1068 return -EINVAL;
1069
1070 base = pci_epf_alloc_space(epf, size, barno, epc_features, type);
1071 if (!base) {
1072 dev_err(dev, "%s intf: Config/Status/SPAD alloc region fail\n",
1073 pci_epc_interface_string(type));
1074 return -ENOMEM;
1075 }
1076
1077 ntb_epc->reg = base;
1078
1079 ctrl = ntb_epc->reg;
1080 ctrl->spad_offset = ctrl_size;
1081 ctrl->spad_count = spad_count;
1082 ctrl->num_mws = ntb->num_mws;
1083 ctrl->db_entry_size = align ? align : 4;
1084 ntb_epc->spad_size = spad_size;
1085
1086 return 0;
1087 }
1088
1089 /**
1090 * epf_ntb_config_spad_bar_alloc_interface() - Allocate memory for config +
1091 * scratchpad region for each of PRIMARY and SECONDARY interface
1092 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
1093 *
1094 * Wrapper for epf_ntb_config_spad_bar_alloc() which allocates memory for
1095 * config + scratchpad region for a specific interface
1096 */
epf_ntb_config_spad_bar_alloc_interface(struct epf_ntb * ntb)1097 static int epf_ntb_config_spad_bar_alloc_interface(struct epf_ntb *ntb)
1098 {
1099 enum pci_epc_interface_type type;
1100 struct device *dev;
1101 int ret;
1102
1103 dev = &ntb->epf->dev;
1104
1105 for (type = PRIMARY_INTERFACE; type <= SECONDARY_INTERFACE; type++) {
1106 ret = epf_ntb_config_spad_bar_alloc(ntb, type);
1107 if (ret) {
1108 dev_err(dev, "%s intf: Config/SPAD BAR alloc failed\n",
1109 pci_epc_interface_string(type));
1110 return ret;
1111 }
1112 }
1113
1114 return 0;
1115 }
1116
1117 /**
1118 * epf_ntb_free_peer_mem() - Free memory allocated in peers outbound address
1119 * space
1120 * @ntb_epc: EPC associated with one of the HOST which holds peers outbound
1121 * address regions
1122 *
1123 * +-----------------+ +---->+----------------+-----------+-----------------+
1124 * | BAR0 | | | Doorbell 1 +-----------> MSI|X ADDRESS 1 |
1125 * +-----------------+ | +----------------+ +-----------------+
1126 * | BAR1 | | | Doorbell 2 +---------+ | |
1127 * +-----------------+----+ +----------------+ | | |
1128 * | BAR2 | | Doorbell 3 +-------+ | +-----------------+
1129 * +-----------------+----+ +----------------+ | +-> MSI|X ADDRESS 2 |
1130 * | BAR3 | | | Doorbell 4 +-----+ | +-----------------+
1131 * +-----------------+ | |----------------+ | | | |
1132 * | BAR4 | | | | | | +-----------------+
1133 * +-----------------+ | | MW1 +---+ | +-->+ MSI|X ADDRESS 3||
1134 * | BAR5 | | | | | | +-----------------+
1135 * +-----------------+ +---->-----------------+ | | | |
1136 * EP CONTROLLER 1 | | | | +-----------------+
1137 * | | | +---->+ MSI|X ADDRESS 4 |
1138 * +----------------+ | +-----------------+
1139 * (A) EP CONTROLLER 2 | | |
1140 * (OB SPACE) | | |
1141 * +-------> MW1 |
1142 * | |
1143 * | |
1144 * (B) +-----------------+
1145 * | |
1146 * | |
1147 * | |
1148 * | |
1149 * | |
1150 * +-----------------+
1151 * PCI Address Space
1152 * (Managed by HOST2)
1153 *
1154 * Free memory allocated in EP CONTROLLER 2 (OB SPACE) in the above diagram.
1155 * It'll free Doorbell 1, Doorbell 2, Doorbell 3, Doorbell 4, MW1 (and MW2, MW3,
1156 * MW4).
1157 */
epf_ntb_free_peer_mem(struct epf_ntb_epc * ntb_epc)1158 static void epf_ntb_free_peer_mem(struct epf_ntb_epc *ntb_epc)
1159 {
1160 struct pci_epf_bar *epf_bar;
1161 void __iomem *mw_addr;
1162 phys_addr_t phys_addr;
1163 enum epf_ntb_bar bar;
1164 enum pci_barno barno;
1165 struct pci_epc *epc;
1166 size_t size;
1167
1168 epc = ntb_epc->epc;
1169
1170 for (bar = BAR_DB_MW1; bar < BAR_MW4; bar++) {
1171 barno = ntb_epc->epf_ntb_bar[bar];
1172 mw_addr = ntb_epc->mw_addr[barno];
1173 epf_bar = &ntb_epc->epf_bar[barno];
1174 phys_addr = epf_bar->phys_addr;
1175 size = epf_bar->size;
1176 if (mw_addr) {
1177 pci_epc_mem_free_addr(epc, phys_addr, mw_addr, size);
1178 ntb_epc->mw_addr[barno] = NULL;
1179 }
1180 }
1181 }
1182
1183 /**
1184 * epf_ntb_db_mw_bar_clear() - Clear doorbell and memory BAR
1185 * @ntb_epc: EPC associated with one of the HOST which holds peer's outbound
1186 * address
1187 *
1188 * +-----------------+ +---->+----------------+-----------+-----------------+
1189 * | BAR0 | | | Doorbell 1 +-----------> MSI|X ADDRESS 1 |
1190 * +-----------------+ | +----------------+ +-----------------+
1191 * | BAR1 | | | Doorbell 2 +---------+ | |
1192 * +-----------------+----+ +----------------+ | | |
1193 * | BAR2 | | Doorbell 3 +-------+ | +-----------------+
1194 * +-----------------+----+ +----------------+ | +-> MSI|X ADDRESS 2 |
1195 * | BAR3 | | | Doorbell 4 +-----+ | +-----------------+
1196 * +-----------------+ | |----------------+ | | | |
1197 * | BAR4 | | | | | | +-----------------+
1198 * +-----------------+ | | MW1 +---+ | +-->+ MSI|X ADDRESS 3||
1199 * | BAR5 | | | | | | +-----------------+
1200 * +-----------------+ +---->-----------------+ | | | |
1201 * EP CONTROLLER 1 | | | | +-----------------+
1202 * | | | +---->+ MSI|X ADDRESS 4 |
1203 * +----------------+ | +-----------------+
1204 * (A) EP CONTROLLER 2 | | |
1205 * (OB SPACE) | | |
1206 * +-------> MW1 |
1207 * | |
1208 * | |
1209 * (B) +-----------------+
1210 * | |
1211 * | |
1212 * | |
1213 * | |
1214 * | |
1215 * +-----------------+
1216 * PCI Address Space
1217 * (Managed by HOST2)
1218 *
1219 * Clear doorbell and memory BARs (remove inbound ATU configuration). In the above
1220 * diagram it clears BAR2 TO BAR5 of EP CONTROLLER 1 (Doorbell BAR, MW1 BAR, MW2
1221 * BAR, MW3 BAR and MW4 BAR).
1222 */
epf_ntb_db_mw_bar_clear(struct epf_ntb_epc * ntb_epc)1223 static void epf_ntb_db_mw_bar_clear(struct epf_ntb_epc *ntb_epc)
1224 {
1225 struct pci_epf_bar *epf_bar;
1226 enum epf_ntb_bar bar;
1227 enum pci_barno barno;
1228 u8 func_no, vfunc_no;
1229 struct pci_epc *epc;
1230
1231 epc = ntb_epc->epc;
1232
1233 func_no = ntb_epc->func_no;
1234 vfunc_no = ntb_epc->vfunc_no;
1235
1236 for (bar = BAR_DB_MW1; bar < BAR_MW4; bar++) {
1237 barno = ntb_epc->epf_ntb_bar[bar];
1238 epf_bar = &ntb_epc->epf_bar[barno];
1239 pci_epc_clear_bar(epc, func_no, vfunc_no, epf_bar);
1240 }
1241 }
1242
1243 /**
1244 * epf_ntb_db_mw_bar_cleanup() - Clear doorbell/memory BAR and free memory
1245 * allocated in peers outbound address space
1246 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
1247 * @type: PRIMARY interface or SECONDARY interface
1248 *
1249 * Wrapper for epf_ntb_db_mw_bar_clear() to clear HOST1's BAR and
1250 * epf_ntb_free_peer_mem() which frees up HOST2 outbound memory.
1251 */
epf_ntb_db_mw_bar_cleanup(struct epf_ntb * ntb,enum pci_epc_interface_type type)1252 static void epf_ntb_db_mw_bar_cleanup(struct epf_ntb *ntb,
1253 enum pci_epc_interface_type type)
1254 {
1255 struct epf_ntb_epc *peer_ntb_epc, *ntb_epc;
1256
1257 ntb_epc = ntb->epc[type];
1258 peer_ntb_epc = ntb->epc[!type];
1259
1260 epf_ntb_db_mw_bar_clear(ntb_epc);
1261 epf_ntb_free_peer_mem(peer_ntb_epc);
1262 }
1263
1264 /**
1265 * epf_ntb_configure_interrupt() - Configure MSI/MSI-X capability
1266 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
1267 * @type: PRIMARY interface or SECONDARY interface
1268 *
1269 * Configure MSI/MSI-X capability for each interface with number of
1270 * interrupts equal to "db_count" configfs entry.
1271 */
epf_ntb_configure_interrupt(struct epf_ntb * ntb,enum pci_epc_interface_type type)1272 static int epf_ntb_configure_interrupt(struct epf_ntb *ntb,
1273 enum pci_epc_interface_type type)
1274 {
1275 const struct pci_epc_features *epc_features;
1276 bool msix_capable, msi_capable;
1277 struct epf_ntb_epc *ntb_epc;
1278 u8 func_no, vfunc_no;
1279 struct pci_epc *epc;
1280 struct device *dev;
1281 u32 db_count;
1282 int ret;
1283
1284 ntb_epc = ntb->epc[type];
1285 dev = &ntb->epf->dev;
1286
1287 epc_features = ntb_epc->epc_features;
1288 msix_capable = epc_features->msix_capable;
1289 msi_capable = epc_features->msi_capable;
1290
1291 if (!(msix_capable || msi_capable)) {
1292 dev_err(dev, "MSI or MSI-X is required for doorbell\n");
1293 return -EINVAL;
1294 }
1295
1296 func_no = ntb_epc->func_no;
1297 vfunc_no = ntb_epc->vfunc_no;
1298
1299 db_count = ntb->db_count;
1300 if (db_count > MAX_DB_COUNT) {
1301 dev_err(dev, "DB count cannot be more than %d\n", MAX_DB_COUNT);
1302 return -EINVAL;
1303 }
1304
1305 ntb->db_count = db_count;
1306 epc = ntb_epc->epc;
1307
1308 if (msi_capable) {
1309 ret = pci_epc_set_msi(epc, func_no, vfunc_no, db_count);
1310 if (ret) {
1311 dev_err(dev, "%s intf: MSI configuration failed\n",
1312 pci_epc_interface_string(type));
1313 return ret;
1314 }
1315 }
1316
1317 if (msix_capable) {
1318 ret = pci_epc_set_msix(epc, func_no, vfunc_no, db_count,
1319 ntb_epc->msix_bar,
1320 ntb_epc->msix_table_offset);
1321 if (ret) {
1322 dev_err(dev, "MSI configuration failed\n");
1323 return ret;
1324 }
1325 }
1326
1327 return 0;
1328 }
1329
1330 /**
1331 * epf_ntb_alloc_peer_mem() - Allocate memory in peer's outbound address space
1332 * @dev: The PCI device.
1333 * @ntb_epc: EPC associated with one of the HOST whose BAR holds peer's outbound
1334 * address
1335 * @bar: BAR of @ntb_epc in for which memory has to be allocated (could be
1336 * BAR_DB_MW1, BAR_MW2, BAR_MW3, BAR_MW4)
1337 * @peer_ntb_epc: EPC associated with HOST whose outbound address space is
1338 * used by @ntb_epc
1339 * @size: Size of the address region that has to be allocated in peers OB SPACE
1340 *
1341 *
1342 * +-----------------+ +---->+----------------+-----------+-----------------+
1343 * | BAR0 | | | Doorbell 1 +-----------> MSI|X ADDRESS 1 |
1344 * +-----------------+ | +----------------+ +-----------------+
1345 * | BAR1 | | | Doorbell 2 +---------+ | |
1346 * +-----------------+----+ +----------------+ | | |
1347 * | BAR2 | | Doorbell 3 +-------+ | +-----------------+
1348 * +-----------------+----+ +----------------+ | +-> MSI|X ADDRESS 2 |
1349 * | BAR3 | | | Doorbell 4 +-----+ | +-----------------+
1350 * +-----------------+ | |----------------+ | | | |
1351 * | BAR4 | | | | | | +-----------------+
1352 * +-----------------+ | | MW1 +---+ | +-->+ MSI|X ADDRESS 3||
1353 * | BAR5 | | | | | | +-----------------+
1354 * +-----------------+ +---->-----------------+ | | | |
1355 * EP CONTROLLER 1 | | | | +-----------------+
1356 * | | | +---->+ MSI|X ADDRESS 4 |
1357 * +----------------+ | +-----------------+
1358 * (A) EP CONTROLLER 2 | | |
1359 * (OB SPACE) | | |
1360 * +-------> MW1 |
1361 * | |
1362 * | |
1363 * (B) +-----------------+
1364 * | |
1365 * | |
1366 * | |
1367 * | |
1368 * | |
1369 * +-----------------+
1370 * PCI Address Space
1371 * (Managed by HOST2)
1372 *
1373 * Allocate memory in OB space of EP CONTROLLER 2 in the above diagram. Allocate
1374 * for Doorbell 1, Doorbell 2, Doorbell 3, Doorbell 4, MW1 (and MW2, MW3, MW4).
1375 */
epf_ntb_alloc_peer_mem(struct device * dev,struct epf_ntb_epc * ntb_epc,enum epf_ntb_bar bar,struct epf_ntb_epc * peer_ntb_epc,size_t size)1376 static int epf_ntb_alloc_peer_mem(struct device *dev,
1377 struct epf_ntb_epc *ntb_epc,
1378 enum epf_ntb_bar bar,
1379 struct epf_ntb_epc *peer_ntb_epc,
1380 size_t size)
1381 {
1382 const struct pci_epc_features *epc_features;
1383 struct pci_epf_bar *epf_bar;
1384 struct pci_epc *peer_epc;
1385 phys_addr_t phys_addr;
1386 void __iomem *mw_addr;
1387 enum pci_barno barno;
1388 size_t align;
1389
1390 epc_features = ntb_epc->epc_features;
1391 align = epc_features->align;
1392
1393 if (size < 128)
1394 size = 128;
1395
1396 if (align)
1397 size = ALIGN(size, align);
1398 else
1399 size = roundup_pow_of_two(size);
1400
1401 peer_epc = peer_ntb_epc->epc;
1402 mw_addr = pci_epc_mem_alloc_addr(peer_epc, &phys_addr, size);
1403 if (!mw_addr) {
1404 dev_err(dev, "%s intf: Failed to allocate OB address\n",
1405 pci_epc_interface_string(peer_ntb_epc->type));
1406 return -ENOMEM;
1407 }
1408
1409 barno = ntb_epc->epf_ntb_bar[bar];
1410 epf_bar = &ntb_epc->epf_bar[barno];
1411 ntb_epc->mw_addr[barno] = mw_addr;
1412
1413 epf_bar->phys_addr = phys_addr;
1414 epf_bar->size = size;
1415 epf_bar->barno = barno;
1416 epf_bar->flags = PCI_BASE_ADDRESS_MEM_TYPE_32;
1417
1418 return 0;
1419 }
1420
1421 /**
1422 * epf_ntb_db_mw_bar_init() - Configure Doorbell and Memory window BARs
1423 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
1424 * @type: PRIMARY interface or SECONDARY interface
1425 *
1426 * Wrapper for epf_ntb_alloc_peer_mem() and pci_epc_set_bar() that allocates
1427 * memory in OB address space of HOST2 and configures BAR of HOST1
1428 */
epf_ntb_db_mw_bar_init(struct epf_ntb * ntb,enum pci_epc_interface_type type)1429 static int epf_ntb_db_mw_bar_init(struct epf_ntb *ntb,
1430 enum pci_epc_interface_type type)
1431 {
1432 const struct pci_epc_features *epc_features;
1433 struct epf_ntb_epc *peer_ntb_epc, *ntb_epc;
1434 struct pci_epf_bar *epf_bar;
1435 struct epf_ntb_ctrl *ctrl;
1436 u32 num_mws, db_count;
1437 enum epf_ntb_bar bar;
1438 enum pci_barno barno;
1439 u8 func_no, vfunc_no;
1440 struct pci_epc *epc;
1441 struct device *dev;
1442 size_t align;
1443 int ret, i;
1444 u64 size;
1445
1446 ntb_epc = ntb->epc[type];
1447 peer_ntb_epc = ntb->epc[!type];
1448
1449 dev = &ntb->epf->dev;
1450 epc_features = ntb_epc->epc_features;
1451 align = epc_features->align;
1452 func_no = ntb_epc->func_no;
1453 vfunc_no = ntb_epc->vfunc_no;
1454 epc = ntb_epc->epc;
1455 num_mws = ntb->num_mws;
1456 db_count = ntb->db_count;
1457
1458 for (bar = BAR_DB_MW1, i = 0; i < num_mws; bar++, i++) {
1459 if (bar == BAR_DB_MW1) {
1460 align = align ? align : 4;
1461 size = db_count * align;
1462 size = ALIGN(size, ntb->mws_size[i]);
1463 ctrl = ntb_epc->reg;
1464 ctrl->mw1_offset = size;
1465 size += ntb->mws_size[i];
1466 } else {
1467 size = ntb->mws_size[i];
1468 }
1469
1470 ret = epf_ntb_alloc_peer_mem(dev, ntb_epc, bar,
1471 peer_ntb_epc, size);
1472 if (ret) {
1473 dev_err(dev, "%s intf: DoorBell mem alloc failed\n",
1474 pci_epc_interface_string(type));
1475 goto err_alloc_peer_mem;
1476 }
1477
1478 barno = ntb_epc->epf_ntb_bar[bar];
1479 epf_bar = &ntb_epc->epf_bar[barno];
1480
1481 ret = pci_epc_set_bar(epc, func_no, vfunc_no, epf_bar);
1482 if (ret) {
1483 dev_err(dev, "%s intf: DoorBell BAR set failed\n",
1484 pci_epc_interface_string(type));
1485 goto err_alloc_peer_mem;
1486 }
1487 }
1488
1489 return 0;
1490
1491 err_alloc_peer_mem:
1492 epf_ntb_db_mw_bar_cleanup(ntb, type);
1493
1494 return ret;
1495 }
1496
1497 /**
1498 * epf_ntb_epc_destroy_interface() - Cleanup NTB EPC interface
1499 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
1500 * @type: PRIMARY interface or SECONDARY interface
1501 *
1502 * Unbind NTB function device from EPC and relinquish reference to pci_epc
1503 * for each of the interface.
1504 */
epf_ntb_epc_destroy_interface(struct epf_ntb * ntb,enum pci_epc_interface_type type)1505 static void epf_ntb_epc_destroy_interface(struct epf_ntb *ntb,
1506 enum pci_epc_interface_type type)
1507 {
1508 struct epf_ntb_epc *ntb_epc;
1509 struct pci_epc *epc;
1510 struct pci_epf *epf;
1511
1512 if (type < 0)
1513 return;
1514
1515 epf = ntb->epf;
1516 ntb_epc = ntb->epc[type];
1517 if (!ntb_epc)
1518 return;
1519 epc = ntb_epc->epc;
1520 pci_epc_remove_epf(epc, epf, type);
1521 pci_epc_put(epc);
1522 }
1523
1524 /**
1525 * epf_ntb_epc_destroy() - Cleanup NTB EPC interface
1526 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
1527 *
1528 * Wrapper for epf_ntb_epc_destroy_interface() to cleanup all the NTB interfaces
1529 */
epf_ntb_epc_destroy(struct epf_ntb * ntb)1530 static void epf_ntb_epc_destroy(struct epf_ntb *ntb)
1531 {
1532 enum pci_epc_interface_type type;
1533
1534 for (type = PRIMARY_INTERFACE; type <= SECONDARY_INTERFACE; type++)
1535 epf_ntb_epc_destroy_interface(ntb, type);
1536 }
1537
1538 /**
1539 * epf_ntb_epc_create_interface() - Create and initialize NTB EPC interface
1540 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
1541 * @epc: struct pci_epc to which a particular NTB interface should be associated
1542 * @type: PRIMARY interface or SECONDARY interface
1543 *
1544 * Allocate memory for NTB EPC interface and initialize it.
1545 */
epf_ntb_epc_create_interface(struct epf_ntb * ntb,struct pci_epc * epc,enum pci_epc_interface_type type)1546 static int epf_ntb_epc_create_interface(struct epf_ntb *ntb,
1547 struct pci_epc *epc,
1548 enum pci_epc_interface_type type)
1549 {
1550 const struct pci_epc_features *epc_features;
1551 struct pci_epf_bar *epf_bar;
1552 struct epf_ntb_epc *ntb_epc;
1553 u8 func_no, vfunc_no;
1554 struct pci_epf *epf;
1555 struct device *dev;
1556
1557 dev = &ntb->epf->dev;
1558
1559 ntb_epc = devm_kzalloc(dev, sizeof(*ntb_epc), GFP_KERNEL);
1560 if (!ntb_epc)
1561 return -ENOMEM;
1562
1563 epf = ntb->epf;
1564 vfunc_no = epf->vfunc_no;
1565 if (type == PRIMARY_INTERFACE) {
1566 func_no = epf->func_no;
1567 epf_bar = epf->bar;
1568 } else {
1569 func_no = epf->sec_epc_func_no;
1570 epf_bar = epf->sec_epc_bar;
1571 }
1572
1573 ntb_epc->linkup = false;
1574 ntb_epc->epc = epc;
1575 ntb_epc->func_no = func_no;
1576 ntb_epc->vfunc_no = vfunc_no;
1577 ntb_epc->type = type;
1578 ntb_epc->epf_bar = epf_bar;
1579 ntb_epc->epf_ntb = ntb;
1580
1581 epc_features = pci_epc_get_features(epc, func_no, vfunc_no);
1582 if (!epc_features)
1583 return -EINVAL;
1584 ntb_epc->epc_features = epc_features;
1585
1586 ntb->epc[type] = ntb_epc;
1587
1588 return 0;
1589 }
1590
1591 /**
1592 * epf_ntb_epc_create() - Create and initialize NTB EPC interface
1593 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
1594 *
1595 * Get a reference to EPC device and bind NTB function device to that EPC
1596 * for each of the interface. It is also a wrapper to
1597 * epf_ntb_epc_create_interface() to allocate memory for NTB EPC interface
1598 * and initialize it
1599 */
epf_ntb_epc_create(struct epf_ntb * ntb)1600 static int epf_ntb_epc_create(struct epf_ntb *ntb)
1601 {
1602 struct pci_epf *epf;
1603 struct device *dev;
1604 int ret;
1605
1606 epf = ntb->epf;
1607 dev = &epf->dev;
1608
1609 ret = epf_ntb_epc_create_interface(ntb, epf->epc, PRIMARY_INTERFACE);
1610 if (ret) {
1611 dev_err(dev, "PRIMARY intf: Fail to create NTB EPC\n");
1612 return ret;
1613 }
1614
1615 ret = epf_ntb_epc_create_interface(ntb, epf->sec_epc,
1616 SECONDARY_INTERFACE);
1617 if (ret) {
1618 dev_err(dev, "SECONDARY intf: Fail to create NTB EPC\n");
1619 goto err_epc_create;
1620 }
1621
1622 return 0;
1623
1624 err_epc_create:
1625 epf_ntb_epc_destroy_interface(ntb, PRIMARY_INTERFACE);
1626
1627 return ret;
1628 }
1629
1630 /**
1631 * epf_ntb_init_epc_bar_interface() - Identify BARs to be used for each of
1632 * the NTB constructs (scratchpad region, doorbell, memorywindow)
1633 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
1634 * @type: PRIMARY interface or SECONDARY interface
1635 *
1636 * Identify the free BARs to be used for each of BAR_CONFIG, BAR_PEER_SPAD,
1637 * BAR_DB_MW1, BAR_MW2, BAR_MW3 and BAR_MW4.
1638 */
epf_ntb_init_epc_bar_interface(struct epf_ntb * ntb,enum pci_epc_interface_type type)1639 static int epf_ntb_init_epc_bar_interface(struct epf_ntb *ntb,
1640 enum pci_epc_interface_type type)
1641 {
1642 const struct pci_epc_features *epc_features;
1643 struct epf_ntb_epc *ntb_epc;
1644 enum pci_barno barno;
1645 enum epf_ntb_bar bar;
1646 struct device *dev;
1647 u32 num_mws;
1648 int i;
1649
1650 barno = BAR_0;
1651 ntb_epc = ntb->epc[type];
1652 num_mws = ntb->num_mws;
1653 dev = &ntb->epf->dev;
1654 epc_features = ntb_epc->epc_features;
1655
1656 /* These are required BARs which are mandatory for NTB functionality */
1657 for (bar = BAR_CONFIG; bar <= BAR_DB_MW1; bar++, barno++) {
1658 barno = pci_epc_get_next_free_bar(epc_features, barno);
1659 if (barno < 0) {
1660 dev_err(dev, "%s intf: Fail to get NTB function BAR\n",
1661 pci_epc_interface_string(type));
1662 return barno;
1663 }
1664 ntb_epc->epf_ntb_bar[bar] = barno;
1665 }
1666
1667 /* These are optional BARs which don't impact NTB functionality */
1668 for (bar = BAR_MW2, i = 1; i < num_mws; bar++, barno++, i++) {
1669 barno = pci_epc_get_next_free_bar(epc_features, barno);
1670 if (barno < 0) {
1671 ntb->num_mws = i;
1672 dev_dbg(dev, "BAR not available for > MW%d\n", i + 1);
1673 }
1674 ntb_epc->epf_ntb_bar[bar] = barno;
1675 }
1676
1677 return 0;
1678 }
1679
1680 /**
1681 * epf_ntb_init_epc_bar() - Identify BARs to be used for each of the NTB
1682 * constructs (scratchpad region, doorbell, memorywindow)
1683 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
1684 *
1685 * Wrapper to epf_ntb_init_epc_bar_interface() to identify the free BARs
1686 * to be used for each of BAR_CONFIG, BAR_PEER_SPAD, BAR_DB_MW1, BAR_MW2,
1687 * BAR_MW3 and BAR_MW4 for all the interfaces.
1688 */
epf_ntb_init_epc_bar(struct epf_ntb * ntb)1689 static int epf_ntb_init_epc_bar(struct epf_ntb *ntb)
1690 {
1691 enum pci_epc_interface_type type;
1692 struct device *dev;
1693 int ret;
1694
1695 dev = &ntb->epf->dev;
1696 for (type = PRIMARY_INTERFACE; type <= SECONDARY_INTERFACE; type++) {
1697 ret = epf_ntb_init_epc_bar_interface(ntb, type);
1698 if (ret) {
1699 dev_err(dev, "Fail to init EPC bar for %s interface\n",
1700 pci_epc_interface_string(type));
1701 return ret;
1702 }
1703 }
1704
1705 return 0;
1706 }
1707
1708 /**
1709 * epf_ntb_epc_init_interface() - Initialize NTB interface
1710 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
1711 * @type: PRIMARY interface or SECONDARY interface
1712 *
1713 * Wrapper to initialize a particular EPC interface and start the workqueue
1714 * to check for commands from host. This function will write to the
1715 * EP controller HW for configuring it.
1716 */
epf_ntb_epc_init_interface(struct epf_ntb * ntb,enum pci_epc_interface_type type)1717 static int epf_ntb_epc_init_interface(struct epf_ntb *ntb,
1718 enum pci_epc_interface_type type)
1719 {
1720 struct epf_ntb_epc *ntb_epc;
1721 u8 func_no, vfunc_no;
1722 struct pci_epc *epc;
1723 struct pci_epf *epf;
1724 struct device *dev;
1725 int ret;
1726
1727 ntb_epc = ntb->epc[type];
1728 epf = ntb->epf;
1729 dev = &epf->dev;
1730 epc = ntb_epc->epc;
1731 func_no = ntb_epc->func_no;
1732 vfunc_no = ntb_epc->vfunc_no;
1733
1734 ret = epf_ntb_config_sspad_bar_set(ntb->epc[type]);
1735 if (ret) {
1736 dev_err(dev, "%s intf: Config/self SPAD BAR init failed\n",
1737 pci_epc_interface_string(type));
1738 return ret;
1739 }
1740
1741 ret = epf_ntb_peer_spad_bar_set(ntb, type);
1742 if (ret) {
1743 dev_err(dev, "%s intf: Peer SPAD BAR init failed\n",
1744 pci_epc_interface_string(type));
1745 goto err_peer_spad_bar_init;
1746 }
1747
1748 ret = epf_ntb_configure_interrupt(ntb, type);
1749 if (ret) {
1750 dev_err(dev, "%s intf: Interrupt configuration failed\n",
1751 pci_epc_interface_string(type));
1752 goto err_peer_spad_bar_init;
1753 }
1754
1755 ret = epf_ntb_db_mw_bar_init(ntb, type);
1756 if (ret) {
1757 dev_err(dev, "%s intf: DB/MW BAR init failed\n",
1758 pci_epc_interface_string(type));
1759 goto err_db_mw_bar_init;
1760 }
1761
1762 if (vfunc_no <= 1) {
1763 ret = pci_epc_write_header(epc, func_no, vfunc_no, epf->header);
1764 if (ret) {
1765 dev_err(dev, "%s intf: Configuration header write failed\n",
1766 pci_epc_interface_string(type));
1767 goto err_write_header;
1768 }
1769 }
1770
1771 INIT_DELAYED_WORK(&ntb->epc[type]->cmd_handler, epf_ntb_cmd_handler);
1772 queue_work(kpcintb_workqueue, &ntb->epc[type]->cmd_handler.work);
1773
1774 return 0;
1775
1776 err_write_header:
1777 epf_ntb_db_mw_bar_cleanup(ntb, type);
1778
1779 err_db_mw_bar_init:
1780 epf_ntb_peer_spad_bar_clear(ntb->epc[type]);
1781
1782 err_peer_spad_bar_init:
1783 epf_ntb_config_sspad_bar_clear(ntb->epc[type]);
1784
1785 return ret;
1786 }
1787
1788 /**
1789 * epf_ntb_epc_cleanup_interface() - Cleanup NTB interface
1790 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
1791 * @type: PRIMARY interface or SECONDARY interface
1792 *
1793 * Wrapper to cleanup a particular NTB interface.
1794 */
epf_ntb_epc_cleanup_interface(struct epf_ntb * ntb,enum pci_epc_interface_type type)1795 static void epf_ntb_epc_cleanup_interface(struct epf_ntb *ntb,
1796 enum pci_epc_interface_type type)
1797 {
1798 struct epf_ntb_epc *ntb_epc;
1799
1800 if (type < 0)
1801 return;
1802
1803 ntb_epc = ntb->epc[type];
1804 cancel_delayed_work(&ntb_epc->cmd_handler);
1805 epf_ntb_db_mw_bar_cleanup(ntb, type);
1806 epf_ntb_peer_spad_bar_clear(ntb_epc);
1807 epf_ntb_config_sspad_bar_clear(ntb_epc);
1808 }
1809
1810 /**
1811 * epf_ntb_epc_cleanup() - Cleanup all NTB interfaces
1812 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
1813 *
1814 * Wrapper to cleanup all NTB interfaces.
1815 */
epf_ntb_epc_cleanup(struct epf_ntb * ntb)1816 static void epf_ntb_epc_cleanup(struct epf_ntb *ntb)
1817 {
1818 enum pci_epc_interface_type type;
1819
1820 for (type = PRIMARY_INTERFACE; type <= SECONDARY_INTERFACE; type++)
1821 epf_ntb_epc_cleanup_interface(ntb, type);
1822 }
1823
1824 /**
1825 * epf_ntb_epc_init() - Initialize all NTB interfaces
1826 * @ntb: NTB device that facilitates communication between HOST1 and HOST2
1827 *
1828 * Wrapper to initialize all NTB interface and start the workqueue
1829 * to check for commands from host.
1830 */
epf_ntb_epc_init(struct epf_ntb * ntb)1831 static int epf_ntb_epc_init(struct epf_ntb *ntb)
1832 {
1833 enum pci_epc_interface_type type;
1834 struct device *dev;
1835 int ret;
1836
1837 dev = &ntb->epf->dev;
1838
1839 for (type = PRIMARY_INTERFACE; type <= SECONDARY_INTERFACE; type++) {
1840 ret = epf_ntb_epc_init_interface(ntb, type);
1841 if (ret) {
1842 dev_err(dev, "%s intf: Failed to initialize\n",
1843 pci_epc_interface_string(type));
1844 goto err_init_type;
1845 }
1846 }
1847
1848 return 0;
1849
1850 err_init_type:
1851 epf_ntb_epc_cleanup_interface(ntb, type - 1);
1852
1853 return ret;
1854 }
1855
1856 /**
1857 * epf_ntb_bind() - Initialize endpoint controller to provide NTB functionality
1858 * @epf: NTB endpoint function device
1859 *
1860 * Initialize both the endpoint controllers associated with NTB function device.
1861 * Invoked when a primary interface or secondary interface is bound to EPC
1862 * device. This function will succeed only when EPC is bound to both the
1863 * interfaces.
1864 */
epf_ntb_bind(struct pci_epf * epf)1865 static int epf_ntb_bind(struct pci_epf *epf)
1866 {
1867 struct epf_ntb *ntb = epf_get_drvdata(epf);
1868 struct device *dev = &epf->dev;
1869 int ret;
1870
1871 if (!epf->epc) {
1872 dev_dbg(dev, "PRIMARY EPC interface not yet bound\n");
1873 return 0;
1874 }
1875
1876 if (!epf->sec_epc) {
1877 dev_dbg(dev, "SECONDARY EPC interface not yet bound\n");
1878 return 0;
1879 }
1880
1881 ret = epf_ntb_epc_create(ntb);
1882 if (ret) {
1883 dev_err(dev, "Failed to create NTB EPC\n");
1884 return ret;
1885 }
1886
1887 ret = epf_ntb_init_epc_bar(ntb);
1888 if (ret) {
1889 dev_err(dev, "Failed to create NTB EPC\n");
1890 goto err_bar_init;
1891 }
1892
1893 ret = epf_ntb_config_spad_bar_alloc_interface(ntb);
1894 if (ret) {
1895 dev_err(dev, "Failed to allocate BAR memory\n");
1896 goto err_bar_alloc;
1897 }
1898
1899 ret = epf_ntb_epc_init(ntb);
1900 if (ret) {
1901 dev_err(dev, "Failed to initialize EPC\n");
1902 goto err_bar_alloc;
1903 }
1904
1905 epf_set_drvdata(epf, ntb);
1906
1907 return 0;
1908
1909 err_bar_alloc:
1910 epf_ntb_config_spad_bar_free(ntb);
1911
1912 err_bar_init:
1913 epf_ntb_epc_destroy(ntb);
1914
1915 return ret;
1916 }
1917
1918 /**
1919 * epf_ntb_unbind() - Cleanup the initialization from epf_ntb_bind()
1920 * @epf: NTB endpoint function device
1921 *
1922 * Cleanup the initialization from epf_ntb_bind()
1923 */
epf_ntb_unbind(struct pci_epf * epf)1924 static void epf_ntb_unbind(struct pci_epf *epf)
1925 {
1926 struct epf_ntb *ntb = epf_get_drvdata(epf);
1927
1928 epf_ntb_epc_cleanup(ntb);
1929 epf_ntb_config_spad_bar_free(ntb);
1930 epf_ntb_epc_destroy(ntb);
1931 }
1932
1933 #define EPF_NTB_R(_name) \
1934 static ssize_t epf_ntb_##_name##_show(struct config_item *item, \
1935 char *page) \
1936 { \
1937 struct config_group *group = to_config_group(item); \
1938 struct epf_ntb *ntb = to_epf_ntb(group); \
1939 \
1940 return sysfs_emit(page, "%d\n", ntb->_name); \
1941 }
1942
1943 #define EPF_NTB_W(_name) \
1944 static ssize_t epf_ntb_##_name##_store(struct config_item *item, \
1945 const char *page, size_t len) \
1946 { \
1947 struct config_group *group = to_config_group(item); \
1948 struct epf_ntb *ntb = to_epf_ntb(group); \
1949 u32 val; \
1950 \
1951 if (kstrtou32(page, 0, &val) < 0) \
1952 return -EINVAL; \
1953 \
1954 ntb->_name = val; \
1955 \
1956 return len; \
1957 }
1958
1959 #define EPF_NTB_MW_R(_name) \
1960 static ssize_t epf_ntb_##_name##_show(struct config_item *item, \
1961 char *page) \
1962 { \
1963 struct config_group *group = to_config_group(item); \
1964 struct epf_ntb *ntb = to_epf_ntb(group); \
1965 int win_no; \
1966 \
1967 sscanf(#_name, "mw%d", &win_no); \
1968 \
1969 return sysfs_emit(page, "%lld\n", ntb->mws_size[win_no - 1]); \
1970 }
1971
1972 #define EPF_NTB_MW_W(_name) \
1973 static ssize_t epf_ntb_##_name##_store(struct config_item *item, \
1974 const char *page, size_t len) \
1975 { \
1976 struct config_group *group = to_config_group(item); \
1977 struct epf_ntb *ntb = to_epf_ntb(group); \
1978 struct device *dev = &ntb->epf->dev; \
1979 int win_no; \
1980 u64 val; \
1981 \
1982 if (kstrtou64(page, 0, &val) < 0) \
1983 return -EINVAL; \
1984 \
1985 if (sscanf(#_name, "mw%d", &win_no) != 1) \
1986 return -EINVAL; \
1987 \
1988 if (ntb->num_mws < win_no) { \
1989 dev_err(dev, "Invalid num_nws: %d value\n", ntb->num_mws); \
1990 return -EINVAL; \
1991 } \
1992 \
1993 ntb->mws_size[win_no - 1] = val; \
1994 \
1995 return len; \
1996 }
1997
epf_ntb_num_mws_store(struct config_item * item,const char * page,size_t len)1998 static ssize_t epf_ntb_num_mws_store(struct config_item *item,
1999 const char *page, size_t len)
2000 {
2001 struct config_group *group = to_config_group(item);
2002 struct epf_ntb *ntb = to_epf_ntb(group);
2003 u32 val;
2004
2005 if (kstrtou32(page, 0, &val) < 0)
2006 return -EINVAL;
2007
2008 if (val > MAX_MW)
2009 return -EINVAL;
2010
2011 ntb->num_mws = val;
2012
2013 return len;
2014 }
2015
2016 EPF_NTB_R(spad_count)
2017 EPF_NTB_W(spad_count)
2018 EPF_NTB_R(db_count)
2019 EPF_NTB_W(db_count)
2020 EPF_NTB_R(num_mws)
2021 EPF_NTB_MW_R(mw1)
2022 EPF_NTB_MW_W(mw1)
2023 EPF_NTB_MW_R(mw2)
2024 EPF_NTB_MW_W(mw2)
2025 EPF_NTB_MW_R(mw3)
2026 EPF_NTB_MW_W(mw3)
2027 EPF_NTB_MW_R(mw4)
2028 EPF_NTB_MW_W(mw4)
2029
2030 CONFIGFS_ATTR(epf_ntb_, spad_count);
2031 CONFIGFS_ATTR(epf_ntb_, db_count);
2032 CONFIGFS_ATTR(epf_ntb_, num_mws);
2033 CONFIGFS_ATTR(epf_ntb_, mw1);
2034 CONFIGFS_ATTR(epf_ntb_, mw2);
2035 CONFIGFS_ATTR(epf_ntb_, mw3);
2036 CONFIGFS_ATTR(epf_ntb_, mw4);
2037
2038 static struct configfs_attribute *epf_ntb_attrs[] = {
2039 &epf_ntb_attr_spad_count,
2040 &epf_ntb_attr_db_count,
2041 &epf_ntb_attr_num_mws,
2042 &epf_ntb_attr_mw1,
2043 &epf_ntb_attr_mw2,
2044 &epf_ntb_attr_mw3,
2045 &epf_ntb_attr_mw4,
2046 NULL,
2047 };
2048
2049 static const struct config_item_type ntb_group_type = {
2050 .ct_attrs = epf_ntb_attrs,
2051 .ct_owner = THIS_MODULE,
2052 };
2053
2054 /**
2055 * epf_ntb_add_cfs() - Add configfs directory specific to NTB
2056 * @epf: NTB endpoint function device
2057 * @group: A pointer to the config_group structure referencing a group of
2058 * config_items of a specific type that belong to a specific sub-system.
2059 *
2060 * Add configfs directory specific to NTB. This directory will hold
2061 * NTB specific properties like db_count, spad_count, num_mws etc.,
2062 */
epf_ntb_add_cfs(struct pci_epf * epf,struct config_group * group)2063 static struct config_group *epf_ntb_add_cfs(struct pci_epf *epf,
2064 struct config_group *group)
2065 {
2066 struct epf_ntb *ntb = epf_get_drvdata(epf);
2067 struct config_group *ntb_group = &ntb->group;
2068 struct device *dev = &epf->dev;
2069
2070 config_group_init_type_name(ntb_group, dev_name(dev), &ntb_group_type);
2071
2072 return ntb_group;
2073 }
2074
2075 /**
2076 * epf_ntb_probe() - Probe NTB function driver
2077 * @epf: NTB endpoint function device
2078 * @id: NTB endpoint function device ID
2079 *
2080 * Probe NTB function driver when endpoint function bus detects a NTB
2081 * endpoint function.
2082 */
epf_ntb_probe(struct pci_epf * epf,const struct pci_epf_device_id * id)2083 static int epf_ntb_probe(struct pci_epf *epf,
2084 const struct pci_epf_device_id *id)
2085 {
2086 struct epf_ntb *ntb;
2087 struct device *dev;
2088
2089 dev = &epf->dev;
2090
2091 ntb = devm_kzalloc(dev, sizeof(*ntb), GFP_KERNEL);
2092 if (!ntb)
2093 return -ENOMEM;
2094
2095 epf->header = &epf_ntb_header;
2096 ntb->epf = epf;
2097 epf_set_drvdata(epf, ntb);
2098
2099 return 0;
2100 }
2101
2102 static const struct pci_epf_ops epf_ntb_ops = {
2103 .bind = epf_ntb_bind,
2104 .unbind = epf_ntb_unbind,
2105 .add_cfs = epf_ntb_add_cfs,
2106 };
2107
2108 static const struct pci_epf_device_id epf_ntb_ids[] = {
2109 {
2110 .name = "pci_epf_ntb",
2111 },
2112 {},
2113 };
2114
2115 static struct pci_epf_driver epf_ntb_driver = {
2116 .driver.name = "pci_epf_ntb",
2117 .probe = epf_ntb_probe,
2118 .id_table = epf_ntb_ids,
2119 .ops = &epf_ntb_ops,
2120 .owner = THIS_MODULE,
2121 };
2122
epf_ntb_init(void)2123 static int __init epf_ntb_init(void)
2124 {
2125 int ret;
2126
2127 kpcintb_workqueue = alloc_workqueue("kpcintb", WQ_MEM_RECLAIM |
2128 WQ_HIGHPRI, 0);
2129 ret = pci_epf_register_driver(&epf_ntb_driver);
2130 if (ret) {
2131 destroy_workqueue(kpcintb_workqueue);
2132 pr_err("Failed to register pci epf ntb driver --> %d\n", ret);
2133 return ret;
2134 }
2135
2136 return 0;
2137 }
2138 module_init(epf_ntb_init);
2139
epf_ntb_exit(void)2140 static void __exit epf_ntb_exit(void)
2141 {
2142 pci_epf_unregister_driver(&epf_ntb_driver);
2143 destroy_workqueue(kpcintb_workqueue);
2144 }
2145 module_exit(epf_ntb_exit);
2146
2147 MODULE_DESCRIPTION("PCI EPF NTB DRIVER");
2148 MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>");
2149 MODULE_LICENSE("GPL v2");
2150