1 // SPDX-License-Identifier: GPL-2.0
2 
3 /* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
4  * Copyright (C) 2018-2021 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) used for IPv4 and IPv6.  There
36  * are 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.  The low-order bit (bit 0) in this bitmap represents a
55  * special global filter, which applies to all traffic.  This is not
56  * used in the current code.  Bit 1, if set, indicates that there is an
57  * entry (i.e. slot containing a system address referring to a rule) for
58  * endpoint 0 in the table.  Bit 3, if set, indicates there is an entry
59  * for endpoint 2, and so on.  Space is set aside in IPA local memory to
60  * hold as many filter table entries as might be required, but typically
61  * they are not all used.
62  *
63  * The AP initializes all entries in a filter table to refer to a "zero"
64  * entry.  Once initialized the modem and AP update the entries for
65  * endpoints they "own" directly.  Currently the AP does not use the
66  * IPA filtering functionality.
67  *
68  *                    IPA Filter Table
69  *                 ----------------------
70  * endpoint bitmap | 0x0000000000000048 | Bits 3 and 6 set (endpoints 2 and 5)
71  *                 |--------------------|
72  * 1st endpoint    | 0x000123456789abc0 | DMA address for modem endpoint 2 rule
73  *                 |--------------------|
74  * 2nd endpoint    | 0x000123456789abf0 | DMA address for AP endpoint 5 rule
75  *                 |--------------------|
76  * (unused)        |                    | (Unused space in filter table)
77  *                 |--------------------|
78  *                          . . .
79  *                 |--------------------|
80  * (unused)        |                    | (Unused space in filter table)
81  *                 ----------------------
82  *
83  * The set of available route rules is divided about equally between the AP
84  * and modem.  The AP initializes all entries in a route table to refer to
85  * a "zero entry".  Once initialized, the modem and AP are responsible for
86  * updating their own entries.  All entries in a route table are usable,
87  * though the AP currently does not use the IPA routing functionality.
88  *
89  *                    IPA Route Table
90  *                 ----------------------
91  * 1st modem route | 0x0001234500001100 | DMA address for first route rule
92  *                 |--------------------|
93  * 2nd modem route | 0x0001234500001140 | DMA address for second route rule
94  *                 |--------------------|
95  *                          . . .
96  *                 |--------------------|
97  * Last modem route| 0x0001234500002280 | DMA address for Nth route rule
98  *                 |--------------------|
99  * 1st AP route    | 0x0001234500001100 | DMA address for route rule (N+1)
100  *                 |--------------------|
101  * 2nd AP route    | 0x0001234500001140 | DMA address for next route rule
102  *                 |--------------------|
103  *                          . . .
104  *                 |--------------------|
105  * Last AP route   | 0x0001234500002280 | DMA address for last route rule
106  *                 ----------------------
107  */
108 
109 /* Assignment of route table entries to the modem and AP */
110 #define IPA_ROUTE_MODEM_MIN		0
111 #define IPA_ROUTE_MODEM_COUNT		8
112 
113 #define IPA_ROUTE_AP_MIN		IPA_ROUTE_MODEM_COUNT
114 #define IPA_ROUTE_AP_COUNT \
115 		(IPA_ROUTE_COUNT_MAX - IPA_ROUTE_MODEM_COUNT)
116 
117 /* Filter or route rules consist of a set of 32-bit values followed by a
118  * 32-bit all-zero rule list terminator.  The "zero rule" is simply an
119  * all-zero rule followed by the list terminator.
120  */
121 #define IPA_ZERO_RULE_SIZE		(2 * sizeof(__le32))
122 
123 /* Check things that can be validated at build time. */
ipa_table_validate_build(void)124 static void ipa_table_validate_build(void)
125 {
126 	/* Filter and route tables contain DMA addresses that refer
127 	 * to filter or route rules.  But the size of a table entry
128 	 * is 64 bits regardless of what the size of an AP DMA address
129 	 * is.  A fixed constant defines the size of an entry, and
130 	 * code in ipa_table_init() uses a pointer to __le64 to
131 	 * initialize tables.
132 	 */
133 	BUILD_BUG_ON(sizeof(dma_addr_t) > sizeof(__le64));
134 
135 	/* A "zero rule" is used to represent no filtering or no routing.
136 	 * It is a 64-bit block of zeroed memory.  Code in ipa_table_init()
137 	 * assumes that it can be written using a pointer to __le64.
138 	 */
139 	BUILD_BUG_ON(IPA_ZERO_RULE_SIZE != sizeof(__le64));
140 
141 	/* Impose a practical limit on the number of routes */
142 	BUILD_BUG_ON(IPA_ROUTE_COUNT_MAX > 32);
143 	/* The modem must be allotted at least one route table entry */
144 	BUILD_BUG_ON(!IPA_ROUTE_MODEM_COUNT);
145 	/* But it can't have more than what is available */
146 	BUILD_BUG_ON(IPA_ROUTE_MODEM_COUNT > IPA_ROUTE_COUNT_MAX);
147 
148 }
149 
150 static bool
ipa_table_valid_one(struct ipa * ipa,enum ipa_mem_id mem_id,bool route)151 ipa_table_valid_one(struct ipa *ipa, enum ipa_mem_id mem_id, bool route)
152 {
153 	const struct ipa_mem *mem = ipa_mem_find(ipa, mem_id);
154 	struct device *dev = &ipa->pdev->dev;
155 	u32 size;
156 
157 	if (route)
158 		size = IPA_ROUTE_COUNT_MAX * sizeof(__le64);
159 	else
160 		size = (1 + IPA_FILTER_COUNT_MAX) * sizeof(__le64);
161 
162 	if (!ipa_cmd_table_valid(ipa, mem, route))
163 		return false;
164 
165 	/* mem->size >= size is sufficient, but we'll demand more */
166 	if (mem->size == size)
167 		return true;
168 
169 	/* Hashed table regions can be zero size if hashing is not supported */
170 	if (ipa_table_hash_support(ipa) && !mem->size)
171 		return true;
172 
173 	dev_err(dev, "%s table region %u size 0x%02x, expected 0x%02x\n",
174 		route ? "route" : "filter", mem_id, mem->size, size);
175 
176 	return false;
177 }
178 
179 /* Verify the filter and route table memory regions are the expected size */
ipa_table_valid(struct ipa * ipa)180 bool ipa_table_valid(struct ipa *ipa)
181 {
182 	bool valid;
183 
184 	valid = ipa_table_valid_one(ipa, IPA_MEM_V4_FILTER, false);
185 	valid = valid && ipa_table_valid_one(ipa, IPA_MEM_V6_FILTER, false);
186 	valid = valid && ipa_table_valid_one(ipa, IPA_MEM_V4_ROUTE, true);
187 	valid = valid && ipa_table_valid_one(ipa, IPA_MEM_V6_ROUTE, true);
188 
189 	if (!ipa_table_hash_support(ipa))
190 		return valid;
191 
192 	valid = valid && ipa_table_valid_one(ipa, IPA_MEM_V4_FILTER_HASHED,
193 					     false);
194 	valid = valid && ipa_table_valid_one(ipa, IPA_MEM_V6_FILTER_HASHED,
195 					     false);
196 	valid = valid && ipa_table_valid_one(ipa, IPA_MEM_V4_ROUTE_HASHED,
197 					     true);
198 	valid = valid && ipa_table_valid_one(ipa, IPA_MEM_V6_ROUTE_HASHED,
199 					     true);
200 
201 	return valid;
202 }
203 
ipa_filter_map_valid(struct ipa * ipa,u32 filter_map)204 bool ipa_filter_map_valid(struct ipa *ipa, u32 filter_map)
205 {
206 	struct device *dev = &ipa->pdev->dev;
207 	u32 count;
208 
209 	if (!filter_map) {
210 		dev_err(dev, "at least one filtering endpoint is required\n");
211 
212 		return false;
213 	}
214 
215 	count = hweight32(filter_map);
216 	if (count > IPA_FILTER_COUNT_MAX) {
217 		dev_err(dev, "too many filtering endpoints (%u, max %u)\n",
218 			count, IPA_FILTER_COUNT_MAX);
219 
220 		return false;
221 	}
222 
223 	return true;
224 }
225 
226 /* Zero entry count means no table, so just return a 0 address */
ipa_table_addr(struct ipa * ipa,bool filter_mask,u16 count)227 static dma_addr_t ipa_table_addr(struct ipa *ipa, bool filter_mask, u16 count)
228 {
229 	u32 skip;
230 
231 	if (!count)
232 		return 0;
233 
234 	WARN_ON(count > max_t(u32, IPA_FILTER_COUNT_MAX, IPA_ROUTE_COUNT_MAX));
235 
236 	/* Skip over the zero rule and possibly the filter mask */
237 	skip = filter_mask ? 1 : 2;
238 
239 	return ipa->table_addr + skip * sizeof(*ipa->table_virt);
240 }
241 
ipa_table_reset_add(struct gsi_trans * trans,bool filter,u16 first,u16 count,enum ipa_mem_id mem_id)242 static void ipa_table_reset_add(struct gsi_trans *trans, bool filter,
243 				u16 first, u16 count, enum ipa_mem_id mem_id)
244 {
245 	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
246 	const struct ipa_mem *mem = ipa_mem_find(ipa, mem_id);
247 	dma_addr_t addr;
248 	u32 offset;
249 	u16 size;
250 
251 	/* Nothing to do if the table memory region is empty */
252 	if (!mem->size)
253 		return;
254 
255 	if (filter)
256 		first++;	/* skip over bitmap */
257 
258 	offset = mem->offset + first * sizeof(__le64);
259 	size = count * sizeof(__le64);
260 	addr = ipa_table_addr(ipa, false, count);
261 
262 	ipa_cmd_dma_shared_mem_add(trans, offset, size, addr, true);
263 }
264 
265 /* Reset entries in a single filter table belonging to either the AP or
266  * modem to refer to the zero entry.  The memory region supplied will be
267  * for the IPv4 and IPv6 non-hashed and hashed filter tables.
268  */
269 static int
ipa_filter_reset_table(struct ipa * ipa,enum ipa_mem_id mem_id,bool modem)270 ipa_filter_reset_table(struct ipa *ipa, enum ipa_mem_id mem_id, bool modem)
271 {
272 	u32 ep_mask = ipa->filter_map;
273 	u32 count = hweight32(ep_mask);
274 	struct gsi_trans *trans;
275 	enum gsi_ee_id ee_id;
276 
277 	trans = ipa_cmd_trans_alloc(ipa, count);
278 	if (!trans) {
279 		dev_err(&ipa->pdev->dev,
280 			"no transaction for %s filter reset\n",
281 			modem ? "modem" : "AP");
282 		return -EBUSY;
283 	}
284 
285 	ee_id = modem ? GSI_EE_MODEM : GSI_EE_AP;
286 	while (ep_mask) {
287 		u32 endpoint_id = __ffs(ep_mask);
288 		struct ipa_endpoint *endpoint;
289 
290 		ep_mask ^= BIT(endpoint_id);
291 
292 		endpoint = &ipa->endpoint[endpoint_id];
293 		if (endpoint->ee_id != ee_id)
294 			continue;
295 
296 		ipa_table_reset_add(trans, true, endpoint_id, 1, mem_id);
297 	}
298 
299 	gsi_trans_commit_wait(trans);
300 
301 	return 0;
302 }
303 
304 /* Theoretically, each filter table could have more filter slots to
305  * update than the maximum number of commands in a transaction.  So
306  * we do each table separately.
307  */
ipa_filter_reset(struct ipa * ipa,bool modem)308 static int ipa_filter_reset(struct ipa *ipa, bool modem)
309 {
310 	int ret;
311 
312 	ret = ipa_filter_reset_table(ipa, IPA_MEM_V4_FILTER, modem);
313 	if (ret)
314 		return ret;
315 
316 	ret = ipa_filter_reset_table(ipa, IPA_MEM_V4_FILTER_HASHED, modem);
317 	if (ret)
318 		return ret;
319 
320 	ret = ipa_filter_reset_table(ipa, IPA_MEM_V6_FILTER, modem);
321 	if (ret)
322 		return ret;
323 	ret = ipa_filter_reset_table(ipa, IPA_MEM_V6_FILTER_HASHED, modem);
324 
325 	return ret;
326 }
327 
328 /* The AP routes and modem routes are each contiguous within the
329  * table.  We can update each table with a single command, and we
330  * won't exceed the per-transaction command limit.
331  * */
ipa_route_reset(struct ipa * ipa,bool modem)332 static int ipa_route_reset(struct ipa *ipa, bool modem)
333 {
334 	struct gsi_trans *trans;
335 	u16 first;
336 	u16 count;
337 
338 	trans = ipa_cmd_trans_alloc(ipa, 4);
339 	if (!trans) {
340 		dev_err(&ipa->pdev->dev,
341 			"no transaction for %s route reset\n",
342 			modem ? "modem" : "AP");
343 		return -EBUSY;
344 	}
345 
346 	if (modem) {
347 		first = IPA_ROUTE_MODEM_MIN;
348 		count = IPA_ROUTE_MODEM_COUNT;
349 	} else {
350 		first = IPA_ROUTE_AP_MIN;
351 		count = IPA_ROUTE_AP_COUNT;
352 	}
353 
354 	ipa_table_reset_add(trans, false, first, count, IPA_MEM_V4_ROUTE);
355 	ipa_table_reset_add(trans, false, first, count,
356 			    IPA_MEM_V4_ROUTE_HASHED);
357 
358 	ipa_table_reset_add(trans, false, first, count, IPA_MEM_V6_ROUTE);
359 	ipa_table_reset_add(trans, false, first, count,
360 			    IPA_MEM_V6_ROUTE_HASHED);
361 
362 	gsi_trans_commit_wait(trans);
363 
364 	return 0;
365 }
366 
ipa_table_reset(struct ipa * ipa,bool modem)367 void ipa_table_reset(struct ipa *ipa, bool modem)
368 {
369 	struct device *dev = &ipa->pdev->dev;
370 	const char *ee_name;
371 	int ret;
372 
373 	ee_name = modem ? "modem" : "AP";
374 
375 	/* Report errors, but reset filter and route tables */
376 	ret = ipa_filter_reset(ipa, modem);
377 	if (ret)
378 		dev_err(dev, "error %d resetting filter table for %s\n",
379 				ret, ee_name);
380 
381 	ret = ipa_route_reset(ipa, modem);
382 	if (ret)
383 		dev_err(dev, "error %d resetting route table for %s\n",
384 				ret, ee_name);
385 }
386 
ipa_table_hash_flush(struct ipa * ipa)387 int ipa_table_hash_flush(struct ipa *ipa)
388 {
389 	u32 offset = ipa_reg_filt_rout_hash_flush_offset(ipa->version);
390 	struct gsi_trans *trans;
391 	u32 val;
392 
393 	if (!ipa_table_hash_support(ipa))
394 		return 0;
395 
396 	trans = ipa_cmd_trans_alloc(ipa, 1);
397 	if (!trans) {
398 		dev_err(&ipa->pdev->dev, "no transaction for hash flush\n");
399 		return -EBUSY;
400 	}
401 
402 	val = IPV4_FILTER_HASH_FMASK | IPV6_FILTER_HASH_FMASK;
403 	val |= IPV6_ROUTER_HASH_FMASK | IPV4_ROUTER_HASH_FMASK;
404 
405 	ipa_cmd_register_write_add(trans, offset, val, val, false);
406 
407 	gsi_trans_commit_wait(trans);
408 
409 	return 0;
410 }
411 
ipa_table_init_add(struct gsi_trans * trans,bool filter,enum ipa_cmd_opcode opcode,enum ipa_mem_id mem_id,enum ipa_mem_id hash_mem_id)412 static void ipa_table_init_add(struct gsi_trans *trans, bool filter,
413 			       enum ipa_cmd_opcode opcode,
414 			       enum ipa_mem_id mem_id,
415 			       enum ipa_mem_id hash_mem_id)
416 {
417 	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
418 	const struct ipa_mem *hash_mem = ipa_mem_find(ipa, hash_mem_id);
419 	const struct ipa_mem *mem = ipa_mem_find(ipa, mem_id);
420 	dma_addr_t hash_addr;
421 	dma_addr_t addr;
422 	u32 zero_offset;
423 	u16 hash_count;
424 	u32 zero_size;
425 	u16 hash_size;
426 	u16 count;
427 	u16 size;
428 
429 	/* Compute the number of table entries to initialize */
430 	if (filter) {
431 		/* The number of filtering endpoints determines number of
432 		 * entries in the filter table; we also add one more "slot"
433 		 * to hold the bitmap itself.  The size of the hashed filter
434 		 * table is either the same as the non-hashed one, or zero.
435 		 */
436 		count = 1 + hweight32(ipa->filter_map);
437 		hash_count = hash_mem->size ? count : 0;
438 	} else {
439 		/* The size of a route table region determines the number
440 		 * of entries it has.
441 		 */
442 		count = mem->size / sizeof(__le64);
443 		hash_count = hash_mem->size / sizeof(__le64);
444 	}
445 	size = count * sizeof(__le64);
446 	hash_size = hash_count * sizeof(__le64);
447 
448 	addr = ipa_table_addr(ipa, filter, count);
449 	hash_addr = ipa_table_addr(ipa, filter, hash_count);
450 
451 	ipa_cmd_table_init_add(trans, opcode, size, mem->offset, addr,
452 			       hash_size, hash_mem->offset, hash_addr);
453 	if (!filter)
454 		return;
455 
456 	/* Zero the unused space in the filter table */
457 	zero_offset = mem->offset + size;
458 	zero_size = mem->size - size;
459 	ipa_cmd_dma_shared_mem_add(trans, zero_offset, zero_size,
460 				   ipa->zero_addr, true);
461 	if (!hash_size)
462 		return;
463 
464 	/* Zero the unused space in the hashed filter table */
465 	zero_offset = hash_mem->offset + hash_size;
466 	zero_size = hash_mem->size - hash_size;
467 	ipa_cmd_dma_shared_mem_add(trans, zero_offset, zero_size,
468 				   ipa->zero_addr, true);
469 }
470 
ipa_table_setup(struct ipa * ipa)471 int ipa_table_setup(struct ipa *ipa)
472 {
473 	struct gsi_trans *trans;
474 
475 	/* We will need at most 8 TREs:
476 	 * - IPv4:
477 	 *     - One for route table initialization (non-hashed and hashed)
478 	 *     - One for filter table initialization (non-hashed and hashed)
479 	 *     - One to zero unused entries in the non-hashed filter table
480 	 *     - One to zero unused entries in the hashed filter table
481 	 * - IPv6:
482 	 *     - One for route table initialization (non-hashed and hashed)
483 	 *     - One for filter table initialization (non-hashed and hashed)
484 	 *     - One to zero unused entries in the non-hashed filter table
485 	 *     - One to zero unused entries in the hashed filter table
486 	 * All platforms support at least 8 TREs in a transaction.
487 	 */
488 	trans = ipa_cmd_trans_alloc(ipa, 8);
489 	if (!trans) {
490 		dev_err(&ipa->pdev->dev, "no transaction for table setup\n");
491 		return -EBUSY;
492 	}
493 
494 	ipa_table_init_add(trans, false, IPA_CMD_IP_V4_ROUTING_INIT,
495 			   IPA_MEM_V4_ROUTE, IPA_MEM_V4_ROUTE_HASHED);
496 
497 	ipa_table_init_add(trans, false, IPA_CMD_IP_V6_ROUTING_INIT,
498 			   IPA_MEM_V6_ROUTE, IPA_MEM_V6_ROUTE_HASHED);
499 
500 	ipa_table_init_add(trans, true, IPA_CMD_IP_V4_FILTER_INIT,
501 			   IPA_MEM_V4_FILTER, IPA_MEM_V4_FILTER_HASHED);
502 
503 	ipa_table_init_add(trans, true, IPA_CMD_IP_V6_FILTER_INIT,
504 			   IPA_MEM_V6_FILTER, IPA_MEM_V6_FILTER_HASHED);
505 
506 	gsi_trans_commit_wait(trans);
507 
508 	return 0;
509 }
510 
511 /**
512  * ipa_filter_tuple_zero() - Zero an endpoint's hashed filter tuple
513  * @endpoint:	Endpoint whose filter hash tuple should be zeroed
514  *
515  * Endpoint must be for the AP (not modem) and support filtering. Updates
516  * the filter hash values without changing route ones.
517  */
ipa_filter_tuple_zero(struct ipa_endpoint * endpoint)518 static void ipa_filter_tuple_zero(struct ipa_endpoint *endpoint)
519 {
520 	u32 endpoint_id = endpoint->endpoint_id;
521 	u32 offset;
522 	u32 val;
523 
524 	offset = IPA_REG_ENDP_FILTER_ROUTER_HSH_CFG_N_OFFSET(endpoint_id);
525 
526 	val = ioread32(endpoint->ipa->reg_virt + offset);
527 
528 	/* Zero all filter-related fields, preserving the rest */
529 	u32p_replace_bits(&val, 0, IPA_REG_ENDP_FILTER_HASH_MSK_ALL);
530 
531 	iowrite32(val, endpoint->ipa->reg_virt + offset);
532 }
533 
534 /* Configure a hashed filter table; there is no ipa_filter_deconfig() */
ipa_filter_config(struct ipa * ipa,bool modem)535 static void ipa_filter_config(struct ipa *ipa, bool modem)
536 {
537 	enum gsi_ee_id ee_id = modem ? GSI_EE_MODEM : GSI_EE_AP;
538 	u32 ep_mask = ipa->filter_map;
539 
540 	if (!ipa_table_hash_support(ipa))
541 		return;
542 
543 	while (ep_mask) {
544 		u32 endpoint_id = __ffs(ep_mask);
545 		struct ipa_endpoint *endpoint;
546 
547 		ep_mask ^= BIT(endpoint_id);
548 
549 		endpoint = &ipa->endpoint[endpoint_id];
550 		if (endpoint->ee_id == ee_id)
551 			ipa_filter_tuple_zero(endpoint);
552 	}
553 }
554 
ipa_route_id_modem(u32 route_id)555 static bool ipa_route_id_modem(u32 route_id)
556 {
557 	return route_id >= IPA_ROUTE_MODEM_MIN &&
558 		route_id <= IPA_ROUTE_MODEM_MIN + IPA_ROUTE_MODEM_COUNT - 1;
559 }
560 
561 /**
562  * ipa_route_tuple_zero() - Zero a hashed route table entry tuple
563  * @ipa:	IPA pointer
564  * @route_id:	Route table entry whose hash tuple should be zeroed
565  *
566  * Updates the route hash values without changing filter ones.
567  */
ipa_route_tuple_zero(struct ipa * ipa,u32 route_id)568 static void ipa_route_tuple_zero(struct ipa *ipa, u32 route_id)
569 {
570 	u32 offset = IPA_REG_ENDP_FILTER_ROUTER_HSH_CFG_N_OFFSET(route_id);
571 	u32 val;
572 
573 	val = ioread32(ipa->reg_virt + offset);
574 
575 	/* Zero all route-related fields, preserving the rest */
576 	u32p_replace_bits(&val, 0, IPA_REG_ENDP_ROUTER_HASH_MSK_ALL);
577 
578 	iowrite32(val, ipa->reg_virt + offset);
579 }
580 
581 /* Configure a hashed route table; there is no ipa_route_deconfig() */
ipa_route_config(struct ipa * ipa,bool modem)582 static void ipa_route_config(struct ipa *ipa, bool modem)
583 {
584 	u32 route_id;
585 
586 	if (!ipa_table_hash_support(ipa))
587 		return;
588 
589 	for (route_id = 0; route_id < IPA_ROUTE_COUNT_MAX; route_id++)
590 		if (ipa_route_id_modem(route_id) == modem)
591 			ipa_route_tuple_zero(ipa, route_id);
592 }
593 
594 /* Configure a filter and route tables; there is no ipa_table_deconfig() */
ipa_table_config(struct ipa * ipa)595 void ipa_table_config(struct ipa *ipa)
596 {
597 	ipa_filter_config(ipa, false);
598 	ipa_filter_config(ipa, true);
599 	ipa_route_config(ipa, false);
600 	ipa_route_config(ipa, true);
601 }
602 
603 /*
604  * Initialize a coherent DMA allocation containing initialized filter and
605  * route table data.  This is used when initializing or resetting the IPA
606  * filter or route table.
607  *
608  * The first entry in a filter table contains a bitmap indicating which
609  * endpoints contain entries in the table.  In addition to that first entry,
610  * there are at most IPA_FILTER_COUNT_MAX entries that follow.  Filter table
611  * entries are 64 bits wide, and (other than the bitmap) contain the DMA
612  * address of a filter rule.  A "zero rule" indicates no filtering, and
613  * consists of 64 bits of zeroes.  When a filter table is initialized (or
614  * reset) its entries are made to refer to the zero rule.
615  *
616  * Each entry in a route table is the DMA address of a routing rule.  For
617  * routing there is also a 64-bit "zero rule" that means no routing, and
618  * when a route table is initialized or reset, its entries are made to refer
619  * to the zero rule.  The zero rule is shared for route and filter tables.
620  *
621  * Note that the IPA hardware requires a filter or route rule address to be
622  * aligned on a 128 byte boundary.  The coherent DMA buffer we allocate here
623  * has a minimum alignment, and we place the zero rule at the base of that
624  * allocated space.  In ipa_table_init() we verify the minimum DMA allocation
625  * meets our requirement.
626  *
627  *	     +-------------------+
628  *	 --> |     zero rule     |
629  *	/    |-------------------|
630  *	|    |     filter mask   |
631  *	|\   |-------------------|
632  *	| ---- zero rule address | \
633  *	|\   |-------------------|  |
634  *	| ---- zero rule address |  |	IPA_FILTER_COUNT_MAX
635  *	|    |-------------------|   >	or IPA_ROUTE_COUNT_MAX,
636  *	|	      ...	    |	whichever is greater
637  *	 \   |-------------------|  |
638  *	  ---- zero rule address | /
639  *	     +-------------------+
640  */
ipa_table_init(struct ipa * ipa)641 int ipa_table_init(struct ipa *ipa)
642 {
643 	u32 count = max_t(u32, IPA_FILTER_COUNT_MAX, IPA_ROUTE_COUNT_MAX);
644 	struct device *dev = &ipa->pdev->dev;
645 	dma_addr_t addr;
646 	__le64 le_addr;
647 	__le64 *virt;
648 	size_t size;
649 
650 	ipa_table_validate_build();
651 
652 	/* The IPA hardware requires route and filter table rules to be
653 	 * aligned on a 128-byte boundary.  We put the "zero rule" at the
654 	 * base of the table area allocated here.  The DMA address returned
655 	 * by dma_alloc_coherent() is guaranteed to be a power-of-2 number
656 	 * of pages, which satisfies the rule alignment requirement.
657 	 */
658 	size = IPA_ZERO_RULE_SIZE + (1 + count) * sizeof(__le64);
659 	virt = dma_alloc_coherent(dev, size, &addr, GFP_KERNEL);
660 	if (!virt)
661 		return -ENOMEM;
662 
663 	ipa->table_virt = virt;
664 	ipa->table_addr = addr;
665 
666 	/* First slot is the zero rule */
667 	*virt++ = 0;
668 
669 	/* Next is the filter table bitmap.  The "soft" bitmap value
670 	 * must be converted to the hardware representation by shifting
671 	 * it left one position.  (Bit 0 repesents global filtering,
672 	 * which is possible but not used.)
673 	 */
674 	*virt++ = cpu_to_le64((u64)ipa->filter_map << 1);
675 
676 	/* All the rest contain the DMA address of the zero rule */
677 	le_addr = cpu_to_le64(addr);
678 	while (count--)
679 		*virt++ = le_addr;
680 
681 	return 0;
682 }
683 
ipa_table_exit(struct ipa * ipa)684 void ipa_table_exit(struct ipa *ipa)
685 {
686 	u32 count = max_t(u32, 1 + IPA_FILTER_COUNT_MAX, IPA_ROUTE_COUNT_MAX);
687 	struct device *dev = &ipa->pdev->dev;
688 	size_t size;
689 
690 	size = IPA_ZERO_RULE_SIZE + (1 + count) * sizeof(__le64);
691 
692 	dma_free_coherent(dev, size, ipa->table_virt, ipa->table_addr);
693 	ipa->table_addr = 0;
694 	ipa->table_virt = NULL;
695 }
696