1// SPDX-License-Identifier: GPL-2.0
2
3/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
4 * Copyright (C) 2018-2023 Linaro Ltd.
5 */
6
7#include <linux/types.h>
8#include <linux/kernel.h>
9#include <linux/bits.h>
10#include <linux/bitops.h>
11#include <linux/bitfield.h>
12#include <linux/io.h>
13#include <linux/build_bug.h>
14#include <linux/device.h>
15#include <linux/dma-mapping.h>
16
17#include "ipa.h"
18#include "ipa_version.h"
19#include "ipa_endpoint.h"
20#include "ipa_table.h"
21#include "ipa_reg.h"
22#include "ipa_mem.h"
23#include "ipa_cmd.h"
24#include "gsi.h"
25#include "gsi_trans.h"
26
27/**
28 * DOC: IPA Filter and Route Tables
29 *
30 * The IPA has tables defined in its local (IPA-resident) memory that define
31 * filter and routing rules. An entry in either of these tables is a little
32 * endian 64-bit "slot" that holds the address of a rule definition. (The
33 * size of these slots is 64 bits regardless of the host DMA address size.)
34 *
35 * Separate tables (both filter and route) are used for IPv4 and IPv6. There
36 * is normally another set of "hashed" filter and route tables, which are
37 * used with a hash of message metadata. Hashed operation is not supported
38 * by all IPA hardware (IPA v4.2 doesn't support hashed tables).
39 *
40 * Rules can be in local memory or in DRAM (system memory). The offset of
41 * an object (such as a route or filter table) in IPA-resident memory must
42 * 128-byte aligned. An object in system memory (such as a route or filter
43 * rule) must be at an 8-byte aligned address. We currently only place
44 * route or filter rules in system memory.
45 *
46 * A rule consists of a contiguous block of 32-bit values terminated with
47 * 32 zero bits. A special "zero entry" rule consisting of 64 zero bits
48 * represents "no filtering" or "no routing," and is the reset value for
49 * filter or route table rules.
50 *
51 * Each filter rule is associated with an AP or modem TX endpoint, though
52 * not all TX endpoints support filtering. The first 64-bit slot in a
53 * filter table is a bitmap indicating which endpoints have entries in
54 * the table. Each set bit in this bitmap indicates the presence of the
55 * address of a filter rule in the memory following the bitmap. Until IPA
56 * v5.0, the low-order bit (bit 0) in this bitmap represents a special
57 * global filter, which applies to all traffic. Otherwise the position of
58 * each set bit represents an endpoint for which a filter rule is defined.
59 *
60 * The global rule is not used in current code, and support for it is
61 * removed starting at IPA v5.0. For IPA v5.0+, the endpoint bitmap
62 * position defines the endpoint ID--i.e. if bit 1 is set in the endpoint
63 * bitmap, endpoint 1 has a filter rule. Older versions of IPA represent
64 * the presence of a filter rule for endpoint X by bit (X + 1) being set.
65 * I.e., bit 1 set indicates the presence of a filter rule for endpoint 0,
66 * and bit 3 set means there is a filter rule present for endpoint 2.
67 *
68 * Each filter table entry has the address of a set of equations that
69 * implement a filter rule. So following the endpoint bitmap there
70 * will be such an address/entry for each endpoint with a set bit in
71 * the bitmap.
72 *
73 * The AP initializes all entries in a filter table to refer to a "zero"
74 * rule. Once initialized, the modem and AP update the entries for
75 * endpoints they "own" directly. Currently the AP does not use the IPA
76 * filtering functionality.
77 *
78 * This diagram shows an example of a filter table with an endpoint
79 * bitmap as defined prior to IPA v5.0.
80 *
81 * IPA Filter Table
82 * ----------------------
83 * endpoint bitmap | 0x0000000000000048 | Bits 3 and 6 set (endpoints 2 and 5)
84 * |--------------------|
85 * 1st endpoint | 0x000123456789abc0 | DMA address for modem endpoint 2 rule
86 * |--------------------|
87 * 2nd endpoint | 0x000123456789abf0 | DMA address for AP endpoint 5 rule
88 * |--------------------|
89 * (unused) | | (Unused space in filter table)
90 * |--------------------|
91 * . . .
92 * |--------------------|
93 * (unused) | | (Unused space in filter table)
94 * ----------------------
95 *
96 * The set of available route rules is divided about equally between the AP
97 * and modem. The AP initializes all entries in a route table to refer to
98 * a "zero entry". Once initialized, the modem and AP are responsible for
99 * updating their own entries. All entries in a route table are usable,
100 * though the AP currently does not use the IPA routing functionality.
101 *
102 * IPA Route Table
103 * ----------------------
104 * 1st modem route | 0x0001234500001100 | DMA address for first route rule
105 * |--------------------|
106 * 2nd modem route | 0x0001234500001140 | DMA address for second route rule
107 * |--------------------|
108 * . . .
109 * |--------------------|
110 * Last modem route| 0x0001234500002280 | DMA address for Nth route rule
111 * |--------------------|
112 * 1st AP route | 0x0001234500001100 | DMA address for route rule (N+1)
113 * |--------------------|
114 * 2nd AP route | 0x0001234500001140 | DMA address for next route rule
115 * |--------------------|
116 * . . .
117 * |--------------------|
118 * Last AP route | 0x0001234500002280 | DMA address for last route rule
119 * ----------------------
120 */
121
122/* Filter or route rules consist of a set of 32-bit values followed by a
123 * 32-bit all-zero rule list terminator. The "zero rule" is simply an
124 * all-zero rule followed by the list terminator.
125 */
126#define IPA_ZERO_RULE_SIZE (2 * sizeof(__le32))
127
128/* Check things that can be validated at build time. */
129static void ipa_table_validate_build(void)
130{
131 /* Filter and route tables contain DMA addresses that refer
132 * to filter or route rules. But the size of a table entry
133 * is 64 bits regardless of what the size of an AP DMA address
134 * is. A fixed constant defines the size of an entry, and
135 * code in ipa_table_init() uses a pointer to __le64 to
136 * initialize tables.
137 */
138 BUILD_BUG_ON(sizeof(dma_addr_t) > sizeof(__le64));
139
140 /* A "zero rule" is used to represent no filtering or no routing.
141 * It is a 64-bit block of zeroed memory. Code in ipa_table_init()
142 * assumes that it can be written using a pointer to __le64.
143 */
144 BUILD_BUG_ON(IPA_ZERO_RULE_SIZE != sizeof(__le64));
145}
146
147static const struct ipa_mem *
148ipa_table_mem(struct ipa *ipa, bool filter, bool hashed, bool ipv6)
149{
150 enum ipa_mem_id mem_id;
151
152 mem_id = filter ? hashed ? ipv6 ? IPA_MEM_V6_FILTER_HASHED
153 : IPA_MEM_V4_FILTER_HASHED
154 : ipv6 ? IPA_MEM_V6_FILTER
155 : IPA_MEM_V4_FILTER
156 : hashed ? ipv6 ? IPA_MEM_V6_ROUTE_HASHED
157 : IPA_MEM_V4_ROUTE_HASHED
158 : ipv6 ? IPA_MEM_V6_ROUTE
159 : IPA_MEM_V4_ROUTE;
160
161 return ipa_mem_find(ipa, mem_id);
162}
163
164bool ipa_filtered_valid(struct ipa *ipa, u64 filtered)
165{
166 struct device *dev = ipa->dev;
167 u32 count;
168
169 if (!filtered) {
170 dev_err(dev, "at least one filtering endpoint is required\n");
171
172 return false;
173 }
174
175 count = hweight64(filtered);
176 if (count > ipa->filter_count) {
177 dev_err(dev, "too many filtering endpoints (%u > %u)\n",
178 count, ipa->filter_count);
179
180 return false;
181 }
182
183 return true;
184}
185
186/* Zero entry count means no table, so just return a 0 address */
187static dma_addr_t ipa_table_addr(struct ipa *ipa, bool filter_mask, u16 count)
188{
189 u32 skip;
190
191 if (!count)
192 return 0;
193
194 WARN_ON(count > max_t(u32, ipa->filter_count, ipa->route_count));
195
196 /* Skip over the zero rule and possibly the filter mask */
197 skip = filter_mask ? 1 : 2;
198
199 return ipa->table_addr + skip * sizeof(*ipa->table_virt);
200}
201
202static void ipa_table_reset_add(struct gsi_trans *trans, bool filter,
203 bool hashed, bool ipv6, u16 first, u16 count)
204{
205 struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
206 const struct ipa_mem *mem;
207 dma_addr_t addr;
208 u32 offset;
209 u16 size;
210
211 /* Nothing to do if the memory region is doesn't exist or is empty */
212 mem = ipa_table_mem(ipa, filter, hashed, ipv6);
213 if (!mem || !mem->size)
214 return;
215
216 if (filter)
217 first++; /* skip over bitmap */
218
219 offset = mem->offset + first * sizeof(__le64);
220 size = count * sizeof(__le64);
221 addr = ipa_table_addr(ipa, filter_mask: false, count);
222
223 ipa_cmd_dma_shared_mem_add(trans, offset, size, addr, toward_ipa: true);
224}
225
226/* Reset entries in a single filter table belonging to either the AP or
227 * modem to refer to the zero entry. The memory region supplied will be
228 * for the IPv4 and IPv6 non-hashed and hashed filter tables.
229 */
230static int
231ipa_filter_reset_table(struct ipa *ipa, bool hashed, bool ipv6, bool modem)
232{
233 u64 ep_mask = ipa->filtered;
234 struct gsi_trans *trans;
235 enum gsi_ee_id ee_id;
236
237 trans = ipa_cmd_trans_alloc(ipa, hweight64(ep_mask));
238 if (!trans) {
239 dev_err(ipa->dev, "no transaction for %s filter reset\n",
240 modem ? "modem" : "AP");
241 return -EBUSY;
242 }
243
244 ee_id = modem ? GSI_EE_MODEM : GSI_EE_AP;
245 while (ep_mask) {
246 u32 endpoint_id = __ffs(ep_mask);
247 struct ipa_endpoint *endpoint;
248
249 ep_mask ^= BIT(endpoint_id);
250
251 endpoint = &ipa->endpoint[endpoint_id];
252 if (endpoint->ee_id != ee_id)
253 continue;
254
255 ipa_table_reset_add(trans, filter: true, hashed, ipv6, first: endpoint_id, count: 1);
256 }
257
258 gsi_trans_commit_wait(trans);
259
260 return 0;
261}
262
263/* Theoretically, each filter table could have more filter slots to
264 * update than the maximum number of commands in a transaction. So
265 * we do each table separately.
266 */
267static int ipa_filter_reset(struct ipa *ipa, bool modem)
268{
269 int ret;
270
271 ret = ipa_filter_reset_table(ipa, hashed: false, ipv6: false, modem);
272 if (ret)
273 return ret;
274
275 ret = ipa_filter_reset_table(ipa, hashed: false, ipv6: true, modem);
276 if (ret || !ipa_table_hash_support(ipa))
277 return ret;
278
279 ret = ipa_filter_reset_table(ipa, hashed: true, ipv6: false, modem);
280 if (ret)
281 return ret;
282
283 return ipa_filter_reset_table(ipa, hashed: true, ipv6: true, modem);
284}
285
286/* The AP routes and modem routes are each contiguous within the
287 * table. We can update each table with a single command, and we
288 * won't exceed the per-transaction command limit.
289 * */
290static int ipa_route_reset(struct ipa *ipa, bool modem)
291{
292 bool hash_support = ipa_table_hash_support(ipa);
293 u32 modem_route_count = ipa->modem_route_count;
294 struct gsi_trans *trans;
295 u16 first;
296 u16 count;
297
298 trans = ipa_cmd_trans_alloc(ipa, tre_count: hash_support ? 4 : 2);
299 if (!trans) {
300 dev_err(ipa->dev, "no transaction for %s route reset\n",
301 modem ? "modem" : "AP");
302 return -EBUSY;
303 }
304
305 if (modem) {
306 first = 0;
307 count = modem_route_count;
308 } else {
309 first = modem_route_count;
310 count = ipa->route_count - modem_route_count;
311 }
312
313 ipa_table_reset_add(trans, filter: false, hashed: false, ipv6: false, first, count);
314 ipa_table_reset_add(trans, filter: false, hashed: false, ipv6: true, first, count);
315
316 if (hash_support) {
317 ipa_table_reset_add(trans, filter: false, hashed: true, ipv6: false, first, count);
318 ipa_table_reset_add(trans, filter: false, hashed: true, ipv6: true, first, count);
319 }
320
321 gsi_trans_commit_wait(trans);
322
323 return 0;
324}
325
326void ipa_table_reset(struct ipa *ipa, bool modem)
327{
328 struct device *dev = ipa->dev;
329 const char *ee_name;
330 int ret;
331
332 ee_name = modem ? "modem" : "AP";
333
334 /* Report errors, but reset filter and route tables */
335 ret = ipa_filter_reset(ipa, modem);
336 if (ret)
337 dev_err(dev, "error %d resetting filter table for %s\n",
338 ret, ee_name);
339
340 ret = ipa_route_reset(ipa, modem);
341 if (ret)
342 dev_err(dev, "error %d resetting route table for %s\n",
343 ret, ee_name);
344}
345
346int ipa_table_hash_flush(struct ipa *ipa)
347{
348 struct gsi_trans *trans;
349 const struct reg *reg;
350 u32 val;
351
352 if (!ipa_table_hash_support(ipa))
353 return 0;
354
355 trans = ipa_cmd_trans_alloc(ipa, tre_count: 1);
356 if (!trans) {
357 dev_err(ipa->dev, "no transaction for hash flush\n");
358 return -EBUSY;
359 }
360
361 if (ipa->version < IPA_VERSION_5_0) {
362 reg = ipa_reg(ipa, reg_id: FILT_ROUT_HASH_FLUSH);
363
364 val = reg_bit(reg, field_id: IPV6_ROUTER_HASH);
365 val |= reg_bit(reg, field_id: IPV6_FILTER_HASH);
366 val |= reg_bit(reg, field_id: IPV4_ROUTER_HASH);
367 val |= reg_bit(reg, field_id: IPV4_FILTER_HASH);
368 } else {
369 reg = ipa_reg(ipa, reg_id: FILT_ROUT_CACHE_FLUSH);
370
371 /* IPA v5.0+ uses a unified cache (both IPv4 and IPv6) */
372 val = reg_bit(reg, field_id: ROUTER_CACHE);
373 val |= reg_bit(reg, field_id: FILTER_CACHE);
374 }
375
376 ipa_cmd_register_write_add(trans, offset: reg_offset(reg), value: val, mask: val, clear_full: false);
377
378 gsi_trans_commit_wait(trans);
379
380 return 0;
381}
382
383static void ipa_table_init_add(struct gsi_trans *trans, bool filter, bool ipv6)
384{
385 struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
386 const struct ipa_mem *hash_mem;
387 enum ipa_cmd_opcode opcode;
388 const struct ipa_mem *mem;
389 dma_addr_t hash_addr;
390 dma_addr_t addr;
391 u32 hash_offset;
392 u32 zero_offset;
393 u16 hash_count;
394 u32 zero_size;
395 u16 hash_size;
396 u16 count;
397 u16 size;
398
399 opcode = filter ? ipv6 ? IPA_CMD_IP_V6_FILTER_INIT
400 : IPA_CMD_IP_V4_FILTER_INIT
401 : ipv6 ? IPA_CMD_IP_V6_ROUTING_INIT
402 : IPA_CMD_IP_V4_ROUTING_INIT;
403
404 /* The non-hashed region will exist (see ipa_table_mem_valid()) */
405 mem = ipa_table_mem(ipa, filter, hashed: false, ipv6);
406 hash_mem = ipa_table_mem(ipa, filter, hashed: true, ipv6);
407 hash_offset = hash_mem ? hash_mem->offset : 0;
408
409 /* Compute the number of table entries to initialize */
410 if (filter) {
411 /* The number of filtering endpoints determines number of
412 * entries in the filter table; we also add one more "slot"
413 * to hold the bitmap itself. The size of the hashed filter
414 * table is either the same as the non-hashed one, or zero.
415 */
416 count = 1 + hweight64(ipa->filtered);
417 hash_count = hash_mem && hash_mem->size ? count : 0;
418 } else {
419 /* The size of a route table region determines the number
420 * of entries it has.
421 */
422 count = mem->size / sizeof(__le64);
423 hash_count = hash_mem ? hash_mem->size / sizeof(__le64) : 0;
424 }
425 size = count * sizeof(__le64);
426 hash_size = hash_count * sizeof(__le64);
427
428 addr = ipa_table_addr(ipa, filter_mask: filter, count);
429 hash_addr = ipa_table_addr(ipa, filter_mask: filter, count: hash_count);
430
431 ipa_cmd_table_init_add(trans, opcode, size, offset: mem->offset, addr,
432 hash_size, hash_offset, hash_addr);
433 if (!filter)
434 return;
435
436 /* Zero the unused space in the filter table */
437 zero_offset = mem->offset + size;
438 zero_size = mem->size - size;
439 ipa_cmd_dma_shared_mem_add(trans, offset: zero_offset, size: zero_size,
440 addr: ipa->zero_addr, toward_ipa: true);
441 if (!hash_size)
442 return;
443
444 /* Zero the unused space in the hashed filter table */
445 zero_offset = hash_offset + hash_size;
446 zero_size = hash_mem->size - hash_size;
447 ipa_cmd_dma_shared_mem_add(trans, offset: zero_offset, size: zero_size,
448 addr: ipa->zero_addr, toward_ipa: true);
449}
450
451int ipa_table_setup(struct ipa *ipa)
452{
453 struct gsi_trans *trans;
454
455 /* We will need at most 8 TREs:
456 * - IPv4:
457 * - One for route table initialization (non-hashed and hashed)
458 * - One for filter table initialization (non-hashed and hashed)
459 * - One to zero unused entries in the non-hashed filter table
460 * - One to zero unused entries in the hashed filter table
461 * - IPv6:
462 * - One for route table initialization (non-hashed and hashed)
463 * - One for filter table initialization (non-hashed and hashed)
464 * - One to zero unused entries in the non-hashed filter table
465 * - One to zero unused entries in the hashed filter table
466 * All platforms support at least 8 TREs in a transaction.
467 */
468 trans = ipa_cmd_trans_alloc(ipa, tre_count: 8);
469 if (!trans) {
470 dev_err(ipa->dev, "no transaction for table setup\n");
471 return -EBUSY;
472 }
473
474 ipa_table_init_add(trans, filter: false, ipv6: false);
475 ipa_table_init_add(trans, filter: false, ipv6: true);
476 ipa_table_init_add(trans, filter: true, ipv6: false);
477 ipa_table_init_add(trans, filter: true, ipv6: true);
478
479 gsi_trans_commit_wait(trans);
480
481 return 0;
482}
483
484/**
485 * ipa_filter_tuple_zero() - Zero an endpoint's hashed filter tuple
486 * @endpoint: Endpoint whose filter hash tuple should be zeroed
487 *
488 * Endpoint must be for the AP (not modem) and support filtering. Updates
489 * the filter hash values without changing route ones.
490 */
491static void ipa_filter_tuple_zero(struct ipa_endpoint *endpoint)
492{
493 u32 endpoint_id = endpoint->endpoint_id;
494 struct ipa *ipa = endpoint->ipa;
495 const struct reg *reg;
496 u32 offset;
497 u32 val;
498
499 if (ipa->version < IPA_VERSION_5_0) {
500 reg = ipa_reg(ipa, reg_id: ENDP_FILTER_ROUTER_HSH_CFG);
501
502 offset = reg_n_offset(reg, n: endpoint_id);
503 val = ioread32(endpoint->ipa->reg_virt + offset);
504
505 /* Zero all filter-related fields, preserving the rest */
506 val &= ~reg_fmask(reg, field_id: FILTER_HASH_MSK_ALL);
507 } else {
508 /* IPA v5.0 separates filter and router cache configuration */
509 reg = ipa_reg(ipa, reg_id: ENDP_FILTER_CACHE_CFG);
510 offset = reg_n_offset(reg, n: endpoint_id);
511
512 /* Zero all filter-related fields */
513 val = 0;
514 }
515
516 iowrite32(val, endpoint->ipa->reg_virt + offset);
517}
518
519/* Configure a hashed filter table; there is no ipa_filter_deconfig() */
520static void ipa_filter_config(struct ipa *ipa, bool modem)
521{
522 enum gsi_ee_id ee_id = modem ? GSI_EE_MODEM : GSI_EE_AP;
523 u64 ep_mask = ipa->filtered;
524
525 if (!ipa_table_hash_support(ipa))
526 return;
527
528 while (ep_mask) {
529 u32 endpoint_id = __ffs(ep_mask);
530 struct ipa_endpoint *endpoint;
531
532 ep_mask ^= BIT(endpoint_id);
533
534 endpoint = &ipa->endpoint[endpoint_id];
535 if (endpoint->ee_id == ee_id)
536 ipa_filter_tuple_zero(endpoint);
537 }
538}
539
540static bool ipa_route_id_modem(struct ipa *ipa, u32 route_id)
541{
542 return route_id < ipa->modem_route_count;
543}
544
545/**
546 * ipa_route_tuple_zero() - Zero a hashed route table entry tuple
547 * @ipa: IPA pointer
548 * @route_id: Route table entry whose hash tuple should be zeroed
549 *
550 * Updates the route hash values without changing filter ones.
551 */
552static void ipa_route_tuple_zero(struct ipa *ipa, u32 route_id)
553{
554 const struct reg *reg;
555 u32 offset;
556 u32 val;
557
558 if (ipa->version < IPA_VERSION_5_0) {
559 reg = ipa_reg(ipa, reg_id: ENDP_FILTER_ROUTER_HSH_CFG);
560 offset = reg_n_offset(reg, n: route_id);
561
562 val = ioread32(ipa->reg_virt + offset);
563
564 /* Zero all route-related fields, preserving the rest */
565 val &= ~reg_fmask(reg, field_id: ROUTER_HASH_MSK_ALL);
566 } else {
567 /* IPA v5.0 separates filter and router cache configuration */
568 reg = ipa_reg(ipa, reg_id: ENDP_ROUTER_CACHE_CFG);
569 offset = reg_n_offset(reg, n: route_id);
570
571 /* Zero all route-related fields */
572 val = 0;
573 }
574
575 iowrite32(val, ipa->reg_virt + offset);
576}
577
578/* Configure a hashed route table; there is no ipa_route_deconfig() */
579static void ipa_route_config(struct ipa *ipa, bool modem)
580{
581 u32 route_id;
582
583 if (!ipa_table_hash_support(ipa))
584 return;
585
586 for (route_id = 0; route_id < ipa->route_count; route_id++)
587 if (ipa_route_id_modem(ipa, route_id) == modem)
588 ipa_route_tuple_zero(ipa, route_id);
589}
590
591/* Configure a filter and route tables; there is no ipa_table_deconfig() */
592void ipa_table_config(struct ipa *ipa)
593{
594 ipa_filter_config(ipa, modem: false);
595 ipa_filter_config(ipa, modem: true);
596 ipa_route_config(ipa, modem: false);
597 ipa_route_config(ipa, modem: true);
598}
599
600/* Verify the sizes of all IPA table filter or routing table memory regions
601 * are valid. If valid, this records the size of the routing table.
602 */
603bool ipa_table_mem_valid(struct ipa *ipa, bool filter)
604{
605 bool hash_support = ipa_table_hash_support(ipa);
606 const struct ipa_mem *mem_hashed;
607 const struct ipa_mem *mem_ipv4;
608 const struct ipa_mem *mem_ipv6;
609 u32 count;
610
611 /* IPv4 and IPv6 non-hashed tables are expected to be defined and
612 * have the same size. Both must have at least two entries (and
613 * would normally have more than that).
614 */
615 mem_ipv4 = ipa_table_mem(ipa, filter, hashed: false, ipv6: false);
616 if (!mem_ipv4)
617 return false;
618
619 mem_ipv6 = ipa_table_mem(ipa, filter, hashed: false, ipv6: true);
620 if (!mem_ipv6)
621 return false;
622
623 if (mem_ipv4->size != mem_ipv6->size)
624 return false;
625
626 /* Compute and record the number of entries for each table type */
627 count = mem_ipv4->size / sizeof(__le64);
628 if (count < 2)
629 return false;
630 if (filter)
631 ipa->filter_count = count - 1; /* Filter map in first entry */
632 else
633 ipa->route_count = count;
634
635 /* Table offset and size must fit in TABLE_INIT command fields */
636 if (!ipa_cmd_table_init_valid(ipa, mem: mem_ipv4, route: !filter))
637 return false;
638
639 /* Make sure the regions are big enough */
640 if (filter) {
641 /* Filter tables must able to hold the endpoint bitmap plus
642 * an entry for each endpoint that supports filtering
643 */
644 if (count < 1 + hweight64(ipa->filtered))
645 return false;
646 } else {
647 /* Routing tables must be able to hold all modem entries,
648 * plus at least one entry for the AP.
649 */
650 if (count < ipa->modem_route_count + 1)
651 return false;
652 }
653
654 /* If hashing is supported, hashed tables are expected to be defined,
655 * and have the same size as non-hashed tables. If hashing is not
656 * supported, hashed tables are expected to have zero size (or not
657 * be defined).
658 */
659 mem_hashed = ipa_table_mem(ipa, filter, hashed: true, ipv6: false);
660 if (hash_support) {
661 if (!mem_hashed || mem_hashed->size != mem_ipv4->size)
662 return false;
663 } else {
664 if (mem_hashed && mem_hashed->size)
665 return false;
666 }
667
668 /* Same check for IPv6 tables */
669 mem_hashed = ipa_table_mem(ipa, filter, hashed: true, ipv6: true);
670 if (hash_support) {
671 if (!mem_hashed || mem_hashed->size != mem_ipv6->size)
672 return false;
673 } else {
674 if (mem_hashed && mem_hashed->size)
675 return false;
676 }
677
678 return true;
679}
680
681/* Initialize a coherent DMA allocation containing initialized filter and
682 * route table data. This is used when initializing or resetting the IPA
683 * filter or route table.
684 *
685 * The first entry in a filter table contains a bitmap indicating which
686 * endpoints contain entries in the table. In addition to that first entry,
687 * there is a fixed maximum number of entries that follow. Filter table
688 * entries are 64 bits wide, and (other than the bitmap) contain the DMA
689 * address of a filter rule. A "zero rule" indicates no filtering, and
690 * consists of 64 bits of zeroes. When a filter table is initialized (or
691 * reset) its entries are made to refer to the zero rule.
692 *
693 * Each entry in a route table is the DMA address of a routing rule. For
694 * routing there is also a 64-bit "zero rule" that means no routing, and
695 * when a route table is initialized or reset, its entries are made to refer
696 * to the zero rule. The zero rule is shared for route and filter tables.
697 *
698 * +-------------------+
699 * --> | zero rule |
700 * / |-------------------|
701 * | | filter mask |
702 * |\ |-------------------|
703 * | ---- zero rule address | \
704 * |\ |-------------------| |
705 * | ---- zero rule address | | Max IPA filter count
706 * | |-------------------| > or IPA route count,
707 * | ... | whichever is greater
708 * \ |-------------------| |
709 * ---- zero rule address | /
710 * +-------------------+
711 */
712int ipa_table_init(struct ipa *ipa)
713{
714 struct device *dev = ipa->dev;
715 dma_addr_t addr;
716 __le64 le_addr;
717 __le64 *virt;
718 size_t size;
719 u32 count;
720
721 ipa_table_validate_build();
722
723 count = max_t(u32, ipa->filter_count, ipa->route_count);
724
725 /* The IPA hardware requires route and filter table rules to be
726 * aligned on a 128-byte boundary. We put the "zero rule" at the
727 * base of the table area allocated here. The DMA address returned
728 * by dma_alloc_coherent() is guaranteed to be a power-of-2 number
729 * of pages, which satisfies the rule alignment requirement.
730 */
731 size = IPA_ZERO_RULE_SIZE + (1 + count) * sizeof(__le64);
732 virt = dma_alloc_coherent(dev, size, dma_handle: &addr, GFP_KERNEL);
733 if (!virt)
734 return -ENOMEM;
735
736 ipa->table_virt = virt;
737 ipa->table_addr = addr;
738
739 /* First slot is the zero rule */
740 *virt++ = 0;
741
742 /* Next is the filter table bitmap. The "soft" bitmap value might
743 * need to be converted to the hardware representation by shifting
744 * it left one position. Prior to IPA v5.0, bit 0 repesents global
745 * filtering, which is possible but not used. IPA v5.0+ eliminated
746 * that option, so there's no shifting required.
747 */
748 if (ipa->version < IPA_VERSION_5_0)
749 *virt++ = cpu_to_le64(ipa->filtered << 1);
750 else
751 *virt++ = cpu_to_le64(ipa->filtered);
752
753 /* All the rest contain the DMA address of the zero rule */
754 le_addr = cpu_to_le64(addr);
755 while (count--)
756 *virt++ = le_addr;
757
758 return 0;
759}
760
761void ipa_table_exit(struct ipa *ipa)
762{
763 u32 count = max_t(u32, 1 + ipa->filter_count, ipa->route_count);
764 struct device *dev = ipa->dev;
765 size_t size;
766
767 size = IPA_ZERO_RULE_SIZE + (1 + count) * sizeof(__le64);
768
769 dma_free_coherent(dev, size, cpu_addr: ipa->table_virt, dma_handle: ipa->table_addr);
770 ipa->table_addr = 0;
771 ipa->table_virt = NULL;
772}
773

source code of linux/drivers/net/ipa/ipa_table.c