xref: /linux/drivers/net/ipa/ipa_cmd.c (revision da1d9caf95def6f0320819cf941c9fd1069ba9e1)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 /* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
4  * Copyright (C) 2019-2021 Linaro Ltd.
5  */
6 
7 #include <linux/types.h>
8 #include <linux/device.h>
9 #include <linux/slab.h>
10 #include <linux/bitfield.h>
11 #include <linux/dma-direction.h>
12 
13 #include "gsi.h"
14 #include "gsi_trans.h"
15 #include "ipa.h"
16 #include "ipa_endpoint.h"
17 #include "ipa_table.h"
18 #include "ipa_cmd.h"
19 #include "ipa_mem.h"
20 
21 /**
22  * DOC:  IPA Immediate Commands
23  *
24  * The AP command TX endpoint is used to issue immediate commands to the IPA.
25  * An immediate command is generally used to request the IPA do something
26  * other than data transfer to another endpoint.
27  *
28  * Immediate commands are represented by GSI transactions just like other
29  * transfer requests, and use a single GSI TRE.  Each immediate command
30  * has a well-defined format, having a payload of a known length.  This
31  * allows the transfer element's length field to be used to hold an
32  * immediate command's opcode.  The payload for a command resides in AP
33  * memory and is described by a single scatterlist entry in its transaction.
34  * Commands do not require a transaction completion callback, and are
35  * (currently) always issued using gsi_trans_commit_wait().
36  */
37 
38 /* Some commands can wait until indicated pipeline stages are clear */
39 enum pipeline_clear_options {
40 	pipeline_clear_hps		= 0x0,
41 	pipeline_clear_src_grp		= 0x1,
42 	pipeline_clear_full		= 0x2,
43 };
44 
45 /* IPA_CMD_IP_V{4,6}_{FILTER,ROUTING}_INIT */
46 
47 struct ipa_cmd_hw_ip_fltrt_init {
48 	__le64 hash_rules_addr;
49 	__le64 flags;
50 	__le64 nhash_rules_addr;
51 };
52 
53 /* Field masks for ipa_cmd_hw_ip_fltrt_init structure fields */
54 #define IP_FLTRT_FLAGS_HASH_SIZE_FMASK			GENMASK_ULL(11, 0)
55 #define IP_FLTRT_FLAGS_HASH_ADDR_FMASK			GENMASK_ULL(27, 12)
56 #define IP_FLTRT_FLAGS_NHASH_SIZE_FMASK			GENMASK_ULL(39, 28)
57 #define IP_FLTRT_FLAGS_NHASH_ADDR_FMASK			GENMASK_ULL(55, 40)
58 
59 /* IPA_CMD_HDR_INIT_LOCAL */
60 
61 struct ipa_cmd_hw_hdr_init_local {
62 	__le64 hdr_table_addr;
63 	__le32 flags;
64 	__le32 reserved;
65 };
66 
67 /* Field masks for ipa_cmd_hw_hdr_init_local structure fields */
68 #define HDR_INIT_LOCAL_FLAGS_TABLE_SIZE_FMASK		GENMASK(11, 0)
69 #define HDR_INIT_LOCAL_FLAGS_HDR_ADDR_FMASK		GENMASK(27, 12)
70 
71 /* IPA_CMD_REGISTER_WRITE */
72 
73 /* For IPA v4.0+, the pipeline clear options are encoded in the opcode */
74 #define REGISTER_WRITE_OPCODE_SKIP_CLEAR_FMASK		GENMASK(8, 8)
75 #define REGISTER_WRITE_OPCODE_CLEAR_OPTION_FMASK	GENMASK(10, 9)
76 
77 struct ipa_cmd_register_write {
78 	__le16 flags;		/* Unused/reserved prior to IPA v4.0 */
79 	__le16 offset;
80 	__le32 value;
81 	__le32 value_mask;
82 	__le32 clear_options;	/* Unused/reserved for IPA v4.0+ */
83 };
84 
85 /* Field masks for ipa_cmd_register_write structure fields */
86 /* The next field is present for IPA v4.0+ */
87 #define REGISTER_WRITE_FLAGS_OFFSET_HIGH_FMASK		GENMASK(14, 11)
88 /* The next field is not present for IPA v4.0+ */
89 #define REGISTER_WRITE_FLAGS_SKIP_CLEAR_FMASK		GENMASK(15, 15)
90 
91 /* The next field and its values are not present for IPA v4.0+ */
92 #define REGISTER_WRITE_CLEAR_OPTIONS_FMASK		GENMASK(1, 0)
93 
94 /* IPA_CMD_IP_PACKET_INIT */
95 
96 struct ipa_cmd_ip_packet_init {
97 	u8 dest_endpoint;
98 	u8 reserved[7];
99 };
100 
101 /* Field masks for ipa_cmd_ip_packet_init dest_endpoint field */
102 #define IPA_PACKET_INIT_DEST_ENDPOINT_FMASK		GENMASK(4, 0)
103 
104 /* IPA_CMD_DMA_SHARED_MEM */
105 
106 /* For IPA v4.0+, this opcode gets modified with pipeline clear options */
107 
108 #define DMA_SHARED_MEM_OPCODE_SKIP_CLEAR_FMASK		GENMASK(8, 8)
109 #define DMA_SHARED_MEM_OPCODE_CLEAR_OPTION_FMASK	GENMASK(10, 9)
110 
111 struct ipa_cmd_hw_dma_mem_mem {
112 	__le16 clear_after_read; /* 0 or DMA_SHARED_MEM_CLEAR_AFTER_READ */
113 	__le16 size;
114 	__le16 local_addr;
115 	__le16 flags;
116 	__le64 system_addr;
117 };
118 
119 /* Flag allowing atomic clear of target region after reading data (v4.0+)*/
120 #define DMA_SHARED_MEM_CLEAR_AFTER_READ			GENMASK(15, 15)
121 
122 /* Field masks for ipa_cmd_hw_dma_mem_mem structure fields */
123 #define DMA_SHARED_MEM_FLAGS_DIRECTION_FMASK		GENMASK(0, 0)
124 /* The next two fields are not present for IPA v4.0+ */
125 #define DMA_SHARED_MEM_FLAGS_SKIP_CLEAR_FMASK		GENMASK(1, 1)
126 #define DMA_SHARED_MEM_FLAGS_CLEAR_OPTIONS_FMASK	GENMASK(3, 2)
127 
128 /* IPA_CMD_IP_PACKET_TAG_STATUS */
129 
130 struct ipa_cmd_ip_packet_tag_status {
131 	__le64 tag;
132 };
133 
134 #define IP_PACKET_TAG_STATUS_TAG_FMASK			GENMASK_ULL(63, 16)
135 
136 /* Immediate command payload */
137 union ipa_cmd_payload {
138 	struct ipa_cmd_hw_ip_fltrt_init table_init;
139 	struct ipa_cmd_hw_hdr_init_local hdr_init_local;
140 	struct ipa_cmd_register_write register_write;
141 	struct ipa_cmd_ip_packet_init ip_packet_init;
142 	struct ipa_cmd_hw_dma_mem_mem dma_shared_mem;
143 	struct ipa_cmd_ip_packet_tag_status ip_packet_tag_status;
144 };
145 
146 static void ipa_cmd_validate_build(void)
147 {
148 	/* The sizes of a filter and route tables need to fit into fields
149 	 * in the ipa_cmd_hw_ip_fltrt_init structure.  Although hashed tables
150 	 * might not be used, non-hashed and hashed tables have the same
151 	 * maximum size.  IPv4 and IPv6 filter tables have the same number
152 	 * of entries, as and IPv4 and IPv6 route tables have the same number
153 	 * of entries.
154 	 */
155 #define TABLE_SIZE	(TABLE_COUNT_MAX * sizeof(__le64))
156 #define TABLE_COUNT_MAX	max_t(u32, IPA_ROUTE_COUNT_MAX, IPA_FILTER_COUNT_MAX)
157 	BUILD_BUG_ON(TABLE_SIZE > field_max(IP_FLTRT_FLAGS_HASH_SIZE_FMASK));
158 	BUILD_BUG_ON(TABLE_SIZE > field_max(IP_FLTRT_FLAGS_NHASH_SIZE_FMASK));
159 #undef TABLE_COUNT_MAX
160 #undef TABLE_SIZE
161 
162 	/* Hashed and non-hashed fields are assumed to be the same size */
163 	BUILD_BUG_ON(field_max(IP_FLTRT_FLAGS_HASH_SIZE_FMASK) !=
164 		     field_max(IP_FLTRT_FLAGS_NHASH_SIZE_FMASK));
165 	BUILD_BUG_ON(field_max(IP_FLTRT_FLAGS_HASH_ADDR_FMASK) !=
166 		     field_max(IP_FLTRT_FLAGS_NHASH_ADDR_FMASK));
167 
168 	/* Valid endpoint numbers must fit in the IP packet init command */
169 	BUILD_BUG_ON(field_max(IPA_PACKET_INIT_DEST_ENDPOINT_FMASK) <
170 		     IPA_ENDPOINT_MAX - 1);
171 }
172 
173 /* Validate a memory region holding a table */
174 bool ipa_cmd_table_valid(struct ipa *ipa, const struct ipa_mem *mem, bool route)
175 {
176 	u32 offset_max = field_max(IP_FLTRT_FLAGS_NHASH_ADDR_FMASK);
177 	u32 size_max = field_max(IP_FLTRT_FLAGS_NHASH_SIZE_FMASK);
178 	const char *table = route ? "route" : "filter";
179 	struct device *dev = &ipa->pdev->dev;
180 
181 	/* Size must fit in the immediate command field that holds it */
182 	if (mem->size > size_max) {
183 		dev_err(dev, "%s table region size too large\n", table);
184 		dev_err(dev, "    (0x%04x > 0x%04x)\n",
185 			mem->size, size_max);
186 
187 		return false;
188 	}
189 
190 	/* Offset must fit in the immediate command field that holds it */
191 	if (mem->offset > offset_max ||
192 	    ipa->mem_offset > offset_max - mem->offset) {
193 		dev_err(dev, "%s table region offset too large\n", table);
194 		dev_err(dev, "    (0x%04x + 0x%04x > 0x%04x)\n",
195 			ipa->mem_offset, mem->offset, offset_max);
196 
197 		return false;
198 	}
199 
200 	/* Entire memory range must fit within IPA-local memory */
201 	if (mem->offset > ipa->mem_size ||
202 	    mem->size > ipa->mem_size - mem->offset) {
203 		dev_err(dev, "%s table region out of range\n", table);
204 		dev_err(dev, "    (0x%04x + 0x%04x > 0x%04x)\n",
205 			mem->offset, mem->size, ipa->mem_size);
206 
207 		return false;
208 	}
209 
210 	return true;
211 }
212 
213 /* Validate the memory region that holds headers */
214 static bool ipa_cmd_header_valid(struct ipa *ipa)
215 {
216 	struct device *dev = &ipa->pdev->dev;
217 	const struct ipa_mem *mem;
218 	u32 offset_max;
219 	u32 size_max;
220 	u32 offset;
221 	u32 size;
222 
223 	/* In ipa_cmd_hdr_init_local_add() we record the offset and size of
224 	 * the header table memory area in an immediate command.  Make sure
225 	 * the offset and size fit in the fields that need to hold them, and
226 	 * that the entire range is within the overall IPA memory range.
227 	 */
228 	offset_max = field_max(HDR_INIT_LOCAL_FLAGS_HDR_ADDR_FMASK);
229 	size_max = field_max(HDR_INIT_LOCAL_FLAGS_TABLE_SIZE_FMASK);
230 
231 	/* The header memory area contains both the modem and AP header
232 	 * regions.  The modem portion defines the address of the region.
233 	 */
234 	mem = ipa_mem_find(ipa, IPA_MEM_MODEM_HEADER);
235 	offset = mem->offset;
236 	size = mem->size;
237 
238 	/* Make sure the offset fits in the IPA command */
239 	if (offset > offset_max || ipa->mem_offset > offset_max - offset) {
240 		dev_err(dev, "header table region offset too large\n");
241 		dev_err(dev, "    (0x%04x + 0x%04x > 0x%04x)\n",
242 			ipa->mem_offset, offset, offset_max);
243 
244 		return false;
245 	}
246 
247 	/* Add the size of the AP portion (if defined) to the combined size */
248 	mem = ipa_mem_find(ipa, IPA_MEM_AP_HEADER);
249 	if (mem)
250 		size += mem->size;
251 
252 	/* Make sure the combined size fits in the IPA command */
253 	if (size > size_max) {
254 		dev_err(dev, "header table region size too large\n");
255 		dev_err(dev, "    (0x%04x > 0x%08x)\n", size, size_max);
256 
257 		return false;
258 	}
259 
260 	/* Make sure the entire combined area fits in IPA memory */
261 	if (size > ipa->mem_size || offset > ipa->mem_size - size) {
262 		dev_err(dev, "header table region out of range\n");
263 		dev_err(dev, "    (0x%04x + 0x%04x > 0x%04x)\n",
264 			offset, size, ipa->mem_size);
265 
266 		return false;
267 	}
268 
269 	return true;
270 }
271 
272 /* Indicate whether an offset can be used with a register_write command */
273 static bool ipa_cmd_register_write_offset_valid(struct ipa *ipa,
274 						const char *name, u32 offset)
275 {
276 	struct ipa_cmd_register_write *payload;
277 	struct device *dev = &ipa->pdev->dev;
278 	u32 offset_max;
279 	u32 bit_count;
280 
281 	/* The maximum offset in a register_write immediate command depends
282 	 * on the version of IPA.  A 16 bit offset is always supported,
283 	 * but starting with IPA v4.0 some additional high-order bits are
284 	 * allowed.
285 	 */
286 	bit_count = BITS_PER_BYTE * sizeof(payload->offset);
287 	if (ipa->version >= IPA_VERSION_4_0)
288 		bit_count += hweight32(REGISTER_WRITE_FLAGS_OFFSET_HIGH_FMASK);
289 	BUILD_BUG_ON(bit_count > 32);
290 	offset_max = ~0U >> (32 - bit_count);
291 
292 	/* Make sure the offset can be represented by the field(s)
293 	 * that holds it.  Also make sure the offset is not outside
294 	 * the overall IPA memory range.
295 	 */
296 	if (offset > offset_max || ipa->mem_offset > offset_max - offset) {
297 		dev_err(dev, "%s offset too large 0x%04x + 0x%04x > 0x%04x)\n",
298 			name, ipa->mem_offset, offset, offset_max);
299 		return false;
300 	}
301 
302 	return true;
303 }
304 
305 /* Check whether offsets passed to register_write are valid */
306 static bool ipa_cmd_register_write_valid(struct ipa *ipa)
307 {
308 	const char *name;
309 	u32 offset;
310 
311 	/* If hashed tables are supported, ensure the hash flush register
312 	 * offset will fit in a register write IPA immediate command.
313 	 */
314 	if (ipa_table_hash_support(ipa)) {
315 		offset = ipa_reg_filt_rout_hash_flush_offset(ipa->version);
316 		name = "filter/route hash flush";
317 		if (!ipa_cmd_register_write_offset_valid(ipa, name, offset))
318 			return false;
319 	}
320 
321 	/* Each endpoint can have a status endpoint associated with it,
322 	 * and this is recorded in an endpoint register.  If the modem
323 	 * crashes, we reset the status endpoint for all modem endpoints
324 	 * using a register write IPA immediate command.  Make sure the
325 	 * worst case (highest endpoint number) offset of that endpoint
326 	 * fits in the register write command field(s) that must hold it.
327 	 */
328 	offset = IPA_REG_ENDP_STATUS_N_OFFSET(IPA_ENDPOINT_COUNT - 1);
329 	name = "maximal endpoint status";
330 	if (!ipa_cmd_register_write_offset_valid(ipa, name, offset))
331 		return false;
332 
333 	return true;
334 }
335 
336 bool ipa_cmd_data_valid(struct ipa *ipa)
337 {
338 	if (!ipa_cmd_header_valid(ipa))
339 		return false;
340 
341 	if (!ipa_cmd_register_write_valid(ipa))
342 		return false;
343 
344 	return true;
345 }
346 
347 
348 int ipa_cmd_pool_init(struct gsi_channel *channel, u32 tre_max)
349 {
350 	struct gsi_trans_info *trans_info = &channel->trans_info;
351 	struct device *dev = channel->gsi->dev;
352 
353 	/* This is as good a place as any to validate build constants */
354 	ipa_cmd_validate_build();
355 
356 	/* Even though command payloads are allocated one at a time,
357 	 * a single transaction can require up to tlv_count of them,
358 	 * so we treat them as if that many can be allocated at once.
359 	 */
360 	return gsi_trans_pool_init_dma(dev, &trans_info->cmd_pool,
361 				       sizeof(union ipa_cmd_payload),
362 				       tre_max, channel->tlv_count);
363 }
364 
365 void ipa_cmd_pool_exit(struct gsi_channel *channel)
366 {
367 	struct gsi_trans_info *trans_info = &channel->trans_info;
368 	struct device *dev = channel->gsi->dev;
369 
370 	gsi_trans_pool_exit_dma(dev, &trans_info->cmd_pool);
371 }
372 
373 static union ipa_cmd_payload *
374 ipa_cmd_payload_alloc(struct ipa *ipa, dma_addr_t *addr)
375 {
376 	struct gsi_trans_info *trans_info;
377 	struct ipa_endpoint *endpoint;
378 
379 	endpoint = ipa->name_map[IPA_ENDPOINT_AP_COMMAND_TX];
380 	trans_info = &ipa->gsi.channel[endpoint->channel_id].trans_info;
381 
382 	return gsi_trans_pool_alloc_dma(&trans_info->cmd_pool, addr);
383 }
384 
385 /* If hash_size is 0, hash_offset and hash_addr ignored. */
386 void ipa_cmd_table_init_add(struct gsi_trans *trans,
387 			    enum ipa_cmd_opcode opcode, u16 size, u32 offset,
388 			    dma_addr_t addr, u16 hash_size, u32 hash_offset,
389 			    dma_addr_t hash_addr)
390 {
391 	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
392 	struct ipa_cmd_hw_ip_fltrt_init *payload;
393 	union ipa_cmd_payload *cmd_payload;
394 	dma_addr_t payload_addr;
395 	u64 val;
396 
397 	/* Record the non-hash table offset and size */
398 	offset += ipa->mem_offset;
399 	val = u64_encode_bits(offset, IP_FLTRT_FLAGS_NHASH_ADDR_FMASK);
400 	val |= u64_encode_bits(size, IP_FLTRT_FLAGS_NHASH_SIZE_FMASK);
401 
402 	/* The hash table offset and address are zero if its size is 0 */
403 	if (hash_size) {
404 		/* Record the hash table offset and size */
405 		hash_offset += ipa->mem_offset;
406 		val |= u64_encode_bits(hash_offset,
407 				       IP_FLTRT_FLAGS_HASH_ADDR_FMASK);
408 		val |= u64_encode_bits(hash_size,
409 				       IP_FLTRT_FLAGS_HASH_SIZE_FMASK);
410 	}
411 
412 	cmd_payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
413 	payload = &cmd_payload->table_init;
414 
415 	/* Fill in all offsets and sizes and the non-hash table address */
416 	if (hash_size)
417 		payload->hash_rules_addr = cpu_to_le64(hash_addr);
418 	payload->flags = cpu_to_le64(val);
419 	payload->nhash_rules_addr = cpu_to_le64(addr);
420 
421 	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
422 			  opcode);
423 }
424 
425 /* Initialize header space in IPA-local memory */
426 void ipa_cmd_hdr_init_local_add(struct gsi_trans *trans, u32 offset, u16 size,
427 				dma_addr_t addr)
428 {
429 	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
430 	enum ipa_cmd_opcode opcode = IPA_CMD_HDR_INIT_LOCAL;
431 	struct ipa_cmd_hw_hdr_init_local *payload;
432 	union ipa_cmd_payload *cmd_payload;
433 	dma_addr_t payload_addr;
434 	u32 flags;
435 
436 	offset += ipa->mem_offset;
437 
438 	/* With this command we tell the IPA where in its local memory the
439 	 * header tables reside.  The content of the buffer provided is
440 	 * also written via DMA into that space.  The IPA hardware owns
441 	 * the table, but the AP must initialize it.
442 	 */
443 	cmd_payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
444 	payload = &cmd_payload->hdr_init_local;
445 
446 	payload->hdr_table_addr = cpu_to_le64(addr);
447 	flags = u32_encode_bits(size, HDR_INIT_LOCAL_FLAGS_TABLE_SIZE_FMASK);
448 	flags |= u32_encode_bits(offset, HDR_INIT_LOCAL_FLAGS_HDR_ADDR_FMASK);
449 	payload->flags = cpu_to_le32(flags);
450 
451 	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
452 			  opcode);
453 }
454 
455 void ipa_cmd_register_write_add(struct gsi_trans *trans, u32 offset, u32 value,
456 				u32 mask, bool clear_full)
457 {
458 	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
459 	struct ipa_cmd_register_write *payload;
460 	union ipa_cmd_payload *cmd_payload;
461 	u32 opcode = IPA_CMD_REGISTER_WRITE;
462 	dma_addr_t payload_addr;
463 	u32 clear_option;
464 	u32 options;
465 	u16 flags;
466 
467 	/* pipeline_clear_src_grp is not used */
468 	clear_option = clear_full ? pipeline_clear_full : pipeline_clear_hps;
469 
470 	/* IPA v4.0+ represents the pipeline clear options in the opcode.  It
471 	 * also supports a larger offset by encoding additional high-order
472 	 * bits in the payload flags field.
473 	 */
474 	if (ipa->version >= IPA_VERSION_4_0) {
475 		u16 offset_high;
476 		u32 val;
477 
478 		/* Opcode encodes pipeline clear options */
479 		/* SKIP_CLEAR is always 0 (don't skip pipeline clear) */
480 		val = u16_encode_bits(clear_option,
481 				      REGISTER_WRITE_OPCODE_CLEAR_OPTION_FMASK);
482 		opcode |= val;
483 
484 		/* Extract the high 4 bits from the offset */
485 		offset_high = (u16)u32_get_bits(offset, GENMASK(19, 16));
486 		offset &= (1 << 16) - 1;
487 
488 		/* Extract the top 4 bits and encode it into the flags field */
489 		flags = u16_encode_bits(offset_high,
490 				REGISTER_WRITE_FLAGS_OFFSET_HIGH_FMASK);
491 		options = 0;	/* reserved */
492 
493 	} else {
494 		flags = 0;	/* SKIP_CLEAR flag is always 0 */
495 		options = u16_encode_bits(clear_option,
496 					  REGISTER_WRITE_CLEAR_OPTIONS_FMASK);
497 	}
498 
499 	cmd_payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
500 	payload = &cmd_payload->register_write;
501 
502 	payload->flags = cpu_to_le16(flags);
503 	payload->offset = cpu_to_le16((u16)offset);
504 	payload->value = cpu_to_le32(value);
505 	payload->value_mask = cpu_to_le32(mask);
506 	payload->clear_options = cpu_to_le32(options);
507 
508 	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
509 			  opcode);
510 }
511 
512 /* Skip IP packet processing on the next data transfer on a TX channel */
513 static void ipa_cmd_ip_packet_init_add(struct gsi_trans *trans, u8 endpoint_id)
514 {
515 	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
516 	enum ipa_cmd_opcode opcode = IPA_CMD_IP_PACKET_INIT;
517 	struct ipa_cmd_ip_packet_init *payload;
518 	union ipa_cmd_payload *cmd_payload;
519 	dma_addr_t payload_addr;
520 
521 	cmd_payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
522 	payload = &cmd_payload->ip_packet_init;
523 
524 	payload->dest_endpoint = u8_encode_bits(endpoint_id,
525 					IPA_PACKET_INIT_DEST_ENDPOINT_FMASK);
526 
527 	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
528 			  opcode);
529 }
530 
531 /* Use a DMA command to read or write a block of IPA-resident memory */
532 void ipa_cmd_dma_shared_mem_add(struct gsi_trans *trans, u32 offset, u16 size,
533 				dma_addr_t addr, bool toward_ipa)
534 {
535 	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
536 	enum ipa_cmd_opcode opcode = IPA_CMD_DMA_SHARED_MEM;
537 	struct ipa_cmd_hw_dma_mem_mem *payload;
538 	union ipa_cmd_payload *cmd_payload;
539 	dma_addr_t payload_addr;
540 	u16 flags;
541 
542 	/* size and offset must fit in 16 bit fields */
543 	WARN_ON(!size);
544 	WARN_ON(size > U16_MAX);
545 	WARN_ON(offset > U16_MAX || ipa->mem_offset > U16_MAX - offset);
546 
547 	offset += ipa->mem_offset;
548 
549 	cmd_payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
550 	payload = &cmd_payload->dma_shared_mem;
551 
552 	/* payload->clear_after_read was reserved prior to IPA v4.0.  It's
553 	 * never needed for current code, so it's 0 regardless of version.
554 	 */
555 	payload->size = cpu_to_le16(size);
556 	payload->local_addr = cpu_to_le16(offset);
557 	/* payload->flags:
558 	 *   direction:		0 = write to IPA, 1 read from IPA
559 	 * Starting at v4.0 these are reserved; either way, all zero:
560 	 *   pipeline clear:	0 = wait for pipeline clear (don't skip)
561 	 *   clear_options:	0 = pipeline_clear_hps
562 	 * Instead, for v4.0+ these are encoded in the opcode.  But again
563 	 * since both values are 0 we won't bother OR'ing them in.
564 	 */
565 	flags = toward_ipa ? 0 : DMA_SHARED_MEM_FLAGS_DIRECTION_FMASK;
566 	payload->flags = cpu_to_le16(flags);
567 	payload->system_addr = cpu_to_le64(addr);
568 
569 	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
570 			  opcode);
571 }
572 
573 static void ipa_cmd_ip_tag_status_add(struct gsi_trans *trans)
574 {
575 	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
576 	enum ipa_cmd_opcode opcode = IPA_CMD_IP_PACKET_TAG_STATUS;
577 	struct ipa_cmd_ip_packet_tag_status *payload;
578 	union ipa_cmd_payload *cmd_payload;
579 	dma_addr_t payload_addr;
580 
581 	cmd_payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
582 	payload = &cmd_payload->ip_packet_tag_status;
583 
584 	payload->tag = le64_encode_bits(0, IP_PACKET_TAG_STATUS_TAG_FMASK);
585 
586 	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
587 			  opcode);
588 }
589 
590 /* Issue a small command TX data transfer */
591 static void ipa_cmd_transfer_add(struct gsi_trans *trans)
592 {
593 	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
594 	enum ipa_cmd_opcode opcode = IPA_CMD_NONE;
595 	union ipa_cmd_payload *payload;
596 	dma_addr_t payload_addr;
597 
598 	/* Just transfer a zero-filled payload structure */
599 	payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
600 
601 	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
602 			  opcode);
603 }
604 
605 /* Add immediate commands to a transaction to clear the hardware pipeline */
606 void ipa_cmd_pipeline_clear_add(struct gsi_trans *trans)
607 {
608 	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
609 	struct ipa_endpoint *endpoint;
610 
611 	/* This will complete when the transfer is received */
612 	reinit_completion(&ipa->completion);
613 
614 	/* Issue a no-op register write command (mask 0 means no write) */
615 	ipa_cmd_register_write_add(trans, 0, 0, 0, true);
616 
617 	/* Send a data packet through the IPA pipeline.  The packet_init
618 	 * command says to send the next packet directly to the exception
619 	 * endpoint without any other IPA processing.  The tag_status
620 	 * command requests that status be generated on completion of
621 	 * that transfer, and that it will be tagged with a value.
622 	 * Finally, the transfer command sends a small packet of data
623 	 * (instead of a command) using the command endpoint.
624 	 */
625 	endpoint = ipa->name_map[IPA_ENDPOINT_AP_LAN_RX];
626 	ipa_cmd_ip_packet_init_add(trans, endpoint->endpoint_id);
627 	ipa_cmd_ip_tag_status_add(trans);
628 	ipa_cmd_transfer_add(trans);
629 }
630 
631 /* Returns the number of commands required to clear the pipeline */
632 u32 ipa_cmd_pipeline_clear_count(void)
633 {
634 	return 4;
635 }
636 
637 void ipa_cmd_pipeline_clear_wait(struct ipa *ipa)
638 {
639 	wait_for_completion(&ipa->completion);
640 }
641 
642 /* Allocate a transaction for the command TX endpoint */
643 struct gsi_trans *ipa_cmd_trans_alloc(struct ipa *ipa, u32 tre_count)
644 {
645 	struct ipa_endpoint *endpoint;
646 
647 	if (WARN_ON(tre_count > IPA_COMMAND_TRANS_TRE_MAX))
648 		return NULL;
649 
650 	endpoint = ipa->name_map[IPA_ENDPOINT_AP_COMMAND_TX];
651 
652 	return gsi_channel_trans_alloc(&ipa->gsi, endpoint->channel_id,
653 				       tre_count, DMA_NONE);
654 }
655