xref: /openbmc/linux/drivers/net/ipa/ipa_cmd.c (revision d9fd5a71)
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, represented by a single GSI TRE.  Each immediate
30  * command has a well-defined format, having a payload of a known length.
31  * This 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 DRAM
33  * and is described by a single scatterlist entry in its transaction.
34  * Commands do not require a transaction completion callback.  To commit
35  * an immediate command transaction, either gsi_trans_commit_wait() or
36  * gsi_trans_commit_wait_timeout() is used.
37  */
38 
39 /* Some commands can wait until indicated pipeline stages are clear */
40 enum pipeline_clear_options {
41 	pipeline_clear_hps		= 0x0,
42 	pipeline_clear_src_grp		= 0x1,
43 	pipeline_clear_full		= 0x2,
44 };
45 
46 /* IPA_CMD_IP_V{4,6}_{FILTER,ROUTING}_INIT */
47 
48 struct ipa_cmd_hw_ip_fltrt_init {
49 	__le64 hash_rules_addr;
50 	__le64 flags;
51 	__le64 nhash_rules_addr;
52 };
53 
54 /* Field masks for ipa_cmd_hw_ip_fltrt_init structure fields */
55 #define IP_FLTRT_FLAGS_HASH_SIZE_FMASK			GENMASK_ULL(11, 0)
56 #define IP_FLTRT_FLAGS_HASH_ADDR_FMASK			GENMASK_ULL(27, 12)
57 #define IP_FLTRT_FLAGS_NHASH_SIZE_FMASK			GENMASK_ULL(39, 28)
58 #define IP_FLTRT_FLAGS_NHASH_ADDR_FMASK			GENMASK_ULL(55, 40)
59 
60 /* IPA_CMD_HDR_INIT_LOCAL */
61 
62 struct ipa_cmd_hw_hdr_init_local {
63 	__le64 hdr_table_addr;
64 	__le32 flags;
65 	__le32 reserved;
66 };
67 
68 /* Field masks for ipa_cmd_hw_hdr_init_local structure fields */
69 #define HDR_INIT_LOCAL_FLAGS_TABLE_SIZE_FMASK		GENMASK(11, 0)
70 #define HDR_INIT_LOCAL_FLAGS_HDR_ADDR_FMASK		GENMASK(27, 12)
71 
72 /* IPA_CMD_REGISTER_WRITE */
73 
74 /* For IPA v4.0+, this opcode gets modified with pipeline clear options */
75 
76 #define REGISTER_WRITE_OPCODE_SKIP_CLEAR_FMASK		GENMASK(8, 8)
77 #define REGISTER_WRITE_OPCODE_CLEAR_OPTION_FMASK	GENMASK(10, 9)
78 
79 struct ipa_cmd_register_write {
80 	__le16 flags;		/* Unused/reserved for IPA v3.5.1 */
81 	__le16 offset;
82 	__le32 value;
83 	__le32 value_mask;
84 	__le32 clear_options;	/* Unused/reserved for IPA v4.0+ */
85 };
86 
87 /* Field masks for ipa_cmd_register_write structure fields */
88 /* The next field is present for IPA v4.0 and above */
89 #define REGISTER_WRITE_FLAGS_OFFSET_HIGH_FMASK		GENMASK(14, 11)
90 /* The next field is present for IPA v3.5.1 only */
91 #define REGISTER_WRITE_FLAGS_SKIP_CLEAR_FMASK		GENMASK(15, 15)
92 
93 /* The next field and its values are present for IPA v3.5.1 only */
94 #define REGISTER_WRITE_CLEAR_OPTIONS_FMASK		GENMASK(1, 0)
95 
96 /* IPA_CMD_IP_PACKET_INIT */
97 
98 struct ipa_cmd_ip_packet_init {
99 	u8 dest_endpoint;
100 	u8 reserved[7];
101 };
102 
103 /* Field masks for ipa_cmd_ip_packet_init dest_endpoint field */
104 #define IPA_PACKET_INIT_DEST_ENDPOINT_FMASK		GENMASK(4, 0)
105 
106 /* IPA_CMD_DMA_SHARED_MEM */
107 
108 /* For IPA v4.0+, this opcode gets modified with pipeline clear options */
109 
110 #define DMA_SHARED_MEM_OPCODE_SKIP_CLEAR_FMASK		GENMASK(8, 8)
111 #define DMA_SHARED_MEM_OPCODE_CLEAR_OPTION_FMASK	GENMASK(10, 9)
112 
113 struct ipa_cmd_hw_dma_mem_mem {
114 	__le16 clear_after_read; /* 0 or DMA_SHARED_MEM_CLEAR_AFTER_READ */
115 	__le16 size;
116 	__le16 local_addr;
117 	__le16 flags;
118 	__le64 system_addr;
119 };
120 
121 /* Flag allowing atomic clear of target region after reading data (v4.0+)*/
122 #define DMA_SHARED_MEM_CLEAR_AFTER_READ			GENMASK(15, 15)
123 
124 /* Field masks for ipa_cmd_hw_dma_mem_mem structure fields */
125 #define DMA_SHARED_MEM_FLAGS_DIRECTION_FMASK		GENMASK(0, 0)
126 /* The next two fields are present for IPA v3.5.1 only. */
127 #define DMA_SHARED_MEM_FLAGS_SKIP_CLEAR_FMASK		GENMASK(1, 1)
128 #define DMA_SHARED_MEM_FLAGS_CLEAR_OPTIONS_FMASK	GENMASK(3, 2)
129 
130 /* IPA_CMD_IP_PACKET_TAG_STATUS */
131 
132 struct ipa_cmd_ip_packet_tag_status {
133 	__le64 tag;
134 };
135 
136 #define IP_PACKET_TAG_STATUS_TAG_FMASK			GENMASK_ULL(63, 16)
137 
138 /* Immediate command payload */
139 union ipa_cmd_payload {
140 	struct ipa_cmd_hw_ip_fltrt_init table_init;
141 	struct ipa_cmd_hw_hdr_init_local hdr_init_local;
142 	struct ipa_cmd_register_write register_write;
143 	struct ipa_cmd_ip_packet_init ip_packet_init;
144 	struct ipa_cmd_hw_dma_mem_mem dma_shared_mem;
145 	struct ipa_cmd_ip_packet_tag_status ip_packet_tag_status;
146 };
147 
148 static void ipa_cmd_validate_build(void)
149 {
150 	/* The sizes of a filter and route tables need to fit into fields
151 	 * in the ipa_cmd_hw_ip_fltrt_init structure.  Although hashed tables
152 	 * might not be used, non-hashed and hashed tables have the same
153 	 * maximum size.  IPv4 and IPv6 filter tables have the same number
154 	 * of entries, as and IPv4 and IPv6 route tables have the same number
155 	 * of entries.
156 	 */
157 #define TABLE_SIZE	(TABLE_COUNT_MAX * IPA_TABLE_ENTRY_SIZE)
158 #define TABLE_COUNT_MAX	max_t(u32, IPA_ROUTE_COUNT_MAX, IPA_FILTER_COUNT_MAX)
159 	BUILD_BUG_ON(TABLE_SIZE > field_max(IP_FLTRT_FLAGS_HASH_SIZE_FMASK));
160 	BUILD_BUG_ON(TABLE_SIZE > field_max(IP_FLTRT_FLAGS_NHASH_SIZE_FMASK));
161 #undef TABLE_COUNT_MAX
162 #undef TABLE_SIZE
163 }
164 
165 #ifdef IPA_VALIDATE
166 
167 /* Validate a memory region holding a table */
168 bool ipa_cmd_table_valid(struct ipa *ipa, const struct ipa_mem *mem,
169 			 bool route, bool ipv6, bool hashed)
170 {
171 	struct device *dev = &ipa->pdev->dev;
172 	u32 offset_max;
173 
174 	offset_max = hashed ? field_max(IP_FLTRT_FLAGS_HASH_ADDR_FMASK)
175 			    : field_max(IP_FLTRT_FLAGS_NHASH_ADDR_FMASK);
176 	if (mem->offset > offset_max ||
177 	    ipa->mem_offset > offset_max - mem->offset) {
178 		dev_err(dev, "IPv%c %s%s table region offset too large "
179 			      "(0x%04x + 0x%04x > 0x%04x)\n",
180 			      ipv6 ? '6' : '4', hashed ? "hashed " : "",
181 			      route ? "route" : "filter",
182 			      ipa->mem_offset, mem->offset, offset_max);
183 		return false;
184 	}
185 
186 	if (mem->offset > ipa->mem_size ||
187 	    mem->size > ipa->mem_size - mem->offset) {
188 		dev_err(dev, "IPv%c %s%s table region out of range "
189 			      "(0x%04x + 0x%04x > 0x%04x)\n",
190 			      ipv6 ? '6' : '4', hashed ? "hashed " : "",
191 			      route ? "route" : "filter",
192 			      mem->offset, mem->size, ipa->mem_size);
193 		return false;
194 	}
195 
196 	return true;
197 }
198 
199 /* Validate the memory region that holds headers */
200 static bool ipa_cmd_header_valid(struct ipa *ipa)
201 {
202 	const struct ipa_mem *mem = &ipa->mem[IPA_MEM_MODEM_HEADER];
203 	struct device *dev = &ipa->pdev->dev;
204 	u32 offset_max;
205 	u32 size_max;
206 	u32 size;
207 
208 	offset_max = field_max(HDR_INIT_LOCAL_FLAGS_HDR_ADDR_FMASK);
209 	if (mem->offset > offset_max ||
210 	    ipa->mem_offset > offset_max - mem->offset) {
211 		dev_err(dev, "header table region offset too large "
212 			      "(0x%04x + 0x%04x > 0x%04x)\n",
213 			      ipa->mem_offset + mem->offset, offset_max);
214 		return false;
215 	}
216 
217 	size_max = field_max(HDR_INIT_LOCAL_FLAGS_TABLE_SIZE_FMASK);
218 	size = ipa->mem[IPA_MEM_MODEM_HEADER].size;
219 	size += ipa->mem[IPA_MEM_AP_HEADER].size;
220 	if (mem->offset > ipa->mem_size || size > ipa->mem_size - mem->offset) {
221 		dev_err(dev, "header table region out of range "
222 			      "(0x%04x + 0x%04x > 0x%04x)\n",
223 			      mem->offset, size, ipa->mem_size);
224 		return false;
225 	}
226 
227 	return true;
228 }
229 
230 /* Indicate whether an offset can be used with a register_write command */
231 static bool ipa_cmd_register_write_offset_valid(struct ipa *ipa,
232 						const char *name, u32 offset)
233 {
234 	struct ipa_cmd_register_write *payload;
235 	struct device *dev = &ipa->pdev->dev;
236 	u32 offset_max;
237 	u32 bit_count;
238 
239 	/* The maximum offset in a register_write immediate command depends
240 	 * on the version of IPA.  IPA v3.5.1 supports a 16 bit offset, but
241 	 * newer versions allow some additional high-order bits.
242 	 */
243 	bit_count = BITS_PER_BYTE * sizeof(payload->offset);
244 	if (ipa->version != IPA_VERSION_3_5_1)
245 		bit_count += hweight32(REGISTER_WRITE_FLAGS_OFFSET_HIGH_FMASK);
246 	BUILD_BUG_ON(bit_count > 32);
247 	offset_max = ~0U >> (32 - bit_count);
248 
249 	/* Make sure the offset can be represented by the field(s)
250 	 * that holds it.  Also make sure the offset is not outside
251 	 * the overall IPA memory range.
252 	 */
253 	if (offset > offset_max || ipa->mem_offset > offset_max - offset) {
254 		dev_err(dev, "%s offset too large 0x%04x + 0x%04x > 0x%04x)\n",
255 			name, ipa->mem_offset, offset, offset_max);
256 		return false;
257 	}
258 
259 	return true;
260 }
261 
262 /* Check whether offsets passed to register_write are valid */
263 static bool ipa_cmd_register_write_valid(struct ipa *ipa)
264 {
265 	const char *name;
266 	u32 offset;
267 
268 	/* If hashed tables are supported, ensure the hash flush register
269 	 * offset will fit in a register write IPA immediate command.
270 	 */
271 	if (ipa_table_hash_support(ipa)) {
272 		offset = ipa_reg_filt_rout_hash_flush_offset(ipa->version);
273 		name = "filter/route hash flush";
274 		if (!ipa_cmd_register_write_offset_valid(ipa, name, offset))
275 			return false;
276 	}
277 
278 	/* Each endpoint can have a status endpoint associated with it,
279 	 * and this is recorded in an endpoint register.  If the modem
280 	 * crashes, we reset the status endpoint for all modem endpoints
281 	 * using a register write IPA immediate command.  Make sure the
282 	 * worst case (highest endpoint number) offset of that endpoint
283 	 * fits in the register write command field(s) that must hold it.
284 	 */
285 	offset = IPA_REG_ENDP_STATUS_N_OFFSET(IPA_ENDPOINT_COUNT - 1);
286 	name = "maximal endpoint status";
287 	if (!ipa_cmd_register_write_offset_valid(ipa, name, offset))
288 		return false;
289 
290 	return true;
291 }
292 
293 bool ipa_cmd_data_valid(struct ipa *ipa)
294 {
295 	if (!ipa_cmd_header_valid(ipa))
296 		return false;
297 
298 	if (!ipa_cmd_register_write_valid(ipa))
299 		return false;
300 
301 	return true;
302 }
303 
304 #endif /* IPA_VALIDATE */
305 
306 int ipa_cmd_pool_init(struct gsi_channel *channel, u32 tre_max)
307 {
308 	struct gsi_trans_info *trans_info = &channel->trans_info;
309 	struct device *dev = channel->gsi->dev;
310 	int ret;
311 
312 	/* This is as good a place as any to validate build constants */
313 	ipa_cmd_validate_build();
314 
315 	/* Even though command payloads are allocated one at a time,
316 	 * a single transaction can require up to tlv_count of them,
317 	 * so we treat them as if that many can be allocated at once.
318 	 */
319 	ret = gsi_trans_pool_init_dma(dev, &trans_info->cmd_pool,
320 				      sizeof(union ipa_cmd_payload),
321 				      tre_max, channel->tlv_count);
322 	if (ret)
323 		return ret;
324 
325 	/* Each TRE needs a command info structure */
326 	ret = gsi_trans_pool_init(&trans_info->info_pool,
327 				   sizeof(struct ipa_cmd_info),
328 				   tre_max, channel->tlv_count);
329 	if (ret)
330 		gsi_trans_pool_exit_dma(dev, &trans_info->cmd_pool);
331 
332 	return ret;
333 }
334 
335 void ipa_cmd_pool_exit(struct gsi_channel *channel)
336 {
337 	struct gsi_trans_info *trans_info = &channel->trans_info;
338 	struct device *dev = channel->gsi->dev;
339 
340 	gsi_trans_pool_exit(&trans_info->info_pool);
341 	gsi_trans_pool_exit_dma(dev, &trans_info->cmd_pool);
342 }
343 
344 static union ipa_cmd_payload *
345 ipa_cmd_payload_alloc(struct ipa *ipa, dma_addr_t *addr)
346 {
347 	struct gsi_trans_info *trans_info;
348 	struct ipa_endpoint *endpoint;
349 
350 	endpoint = ipa->name_map[IPA_ENDPOINT_AP_COMMAND_TX];
351 	trans_info = &ipa->gsi.channel[endpoint->channel_id].trans_info;
352 
353 	return gsi_trans_pool_alloc_dma(&trans_info->cmd_pool, addr);
354 }
355 
356 /* If hash_size is 0, hash_offset and hash_addr ignored. */
357 void ipa_cmd_table_init_add(struct gsi_trans *trans,
358 			    enum ipa_cmd_opcode opcode, u16 size, u32 offset,
359 			    dma_addr_t addr, u16 hash_size, u32 hash_offset,
360 			    dma_addr_t hash_addr)
361 {
362 	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
363 	enum dma_data_direction direction = DMA_TO_DEVICE;
364 	struct ipa_cmd_hw_ip_fltrt_init *payload;
365 	union ipa_cmd_payload *cmd_payload;
366 	dma_addr_t payload_addr;
367 	u64 val;
368 
369 	/* Record the non-hash table offset and size */
370 	offset += ipa->mem_offset;
371 	val = u64_encode_bits(offset, IP_FLTRT_FLAGS_NHASH_ADDR_FMASK);
372 	val |= u64_encode_bits(size, IP_FLTRT_FLAGS_NHASH_SIZE_FMASK);
373 
374 	/* The hash table offset and address are zero if its size is 0 */
375 	if (hash_size) {
376 		/* Record the hash table offset and size */
377 		hash_offset += ipa->mem_offset;
378 		val |= u64_encode_bits(hash_offset,
379 				       IP_FLTRT_FLAGS_HASH_ADDR_FMASK);
380 		val |= u64_encode_bits(hash_size,
381 				       IP_FLTRT_FLAGS_HASH_SIZE_FMASK);
382 	}
383 
384 	cmd_payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
385 	payload = &cmd_payload->table_init;
386 
387 	/* Fill in all offsets and sizes and the non-hash table address */
388 	if (hash_size)
389 		payload->hash_rules_addr = cpu_to_le64(hash_addr);
390 	payload->flags = cpu_to_le64(val);
391 	payload->nhash_rules_addr = cpu_to_le64(addr);
392 
393 	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
394 			  direction, opcode);
395 }
396 
397 /* Initialize header space in IPA-local memory */
398 void ipa_cmd_hdr_init_local_add(struct gsi_trans *trans, u32 offset, u16 size,
399 				dma_addr_t addr)
400 {
401 	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
402 	enum ipa_cmd_opcode opcode = IPA_CMD_HDR_INIT_LOCAL;
403 	enum dma_data_direction direction = DMA_TO_DEVICE;
404 	struct ipa_cmd_hw_hdr_init_local *payload;
405 	union ipa_cmd_payload *cmd_payload;
406 	dma_addr_t payload_addr;
407 	u32 flags;
408 
409 	offset += ipa->mem_offset;
410 
411 	/* With this command we tell the IPA where in its local memory the
412 	 * header tables reside.  The content of the buffer provided is
413 	 * also written via DMA into that space.  The IPA hardware owns
414 	 * the table, but the AP must initialize it.
415 	 */
416 	cmd_payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
417 	payload = &cmd_payload->hdr_init_local;
418 
419 	payload->hdr_table_addr = cpu_to_le64(addr);
420 	flags = u32_encode_bits(size, HDR_INIT_LOCAL_FLAGS_TABLE_SIZE_FMASK);
421 	flags |= u32_encode_bits(offset, HDR_INIT_LOCAL_FLAGS_HDR_ADDR_FMASK);
422 	payload->flags = cpu_to_le32(flags);
423 
424 	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
425 			  direction, opcode);
426 }
427 
428 void ipa_cmd_register_write_add(struct gsi_trans *trans, u32 offset, u32 value,
429 				u32 mask, bool clear_full)
430 {
431 	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
432 	struct ipa_cmd_register_write *payload;
433 	union ipa_cmd_payload *cmd_payload;
434 	u32 opcode = IPA_CMD_REGISTER_WRITE;
435 	dma_addr_t payload_addr;
436 	u32 clear_option;
437 	u32 options;
438 	u16 flags;
439 
440 	/* pipeline_clear_src_grp is not used */
441 	clear_option = clear_full ? pipeline_clear_full : pipeline_clear_hps;
442 
443 	if (ipa->version != IPA_VERSION_3_5_1) {
444 		u16 offset_high;
445 		u32 val;
446 
447 		/* Opcode encodes pipeline clear options */
448 		/* SKIP_CLEAR is always 0 (don't skip pipeline clear) */
449 		val = u16_encode_bits(clear_option,
450 				      REGISTER_WRITE_OPCODE_CLEAR_OPTION_FMASK);
451 		opcode |= val;
452 
453 		/* Extract the high 4 bits from the offset */
454 		offset_high = (u16)u32_get_bits(offset, GENMASK(19, 16));
455 		offset &= (1 << 16) - 1;
456 
457 		/* Extract the top 4 bits and encode it into the flags field */
458 		flags = u16_encode_bits(offset_high,
459 				REGISTER_WRITE_FLAGS_OFFSET_HIGH_FMASK);
460 		options = 0;	/* reserved */
461 
462 	} else {
463 		flags = 0;	/* SKIP_CLEAR flag is always 0 */
464 		options = u16_encode_bits(clear_option,
465 					  REGISTER_WRITE_CLEAR_OPTIONS_FMASK);
466 	}
467 
468 	cmd_payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
469 	payload = &cmd_payload->register_write;
470 
471 	payload->flags = cpu_to_le16(flags);
472 	payload->offset = cpu_to_le16((u16)offset);
473 	payload->value = cpu_to_le32(value);
474 	payload->value_mask = cpu_to_le32(mask);
475 	payload->clear_options = cpu_to_le32(options);
476 
477 	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
478 			  DMA_NONE, opcode);
479 }
480 
481 /* Skip IP packet processing on the next data transfer on a TX channel */
482 static void ipa_cmd_ip_packet_init_add(struct gsi_trans *trans, u8 endpoint_id)
483 {
484 	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
485 	enum ipa_cmd_opcode opcode = IPA_CMD_IP_PACKET_INIT;
486 	enum dma_data_direction direction = DMA_TO_DEVICE;
487 	struct ipa_cmd_ip_packet_init *payload;
488 	union ipa_cmd_payload *cmd_payload;
489 	dma_addr_t payload_addr;
490 
491 	/* assert(endpoint_id <
492 		  field_max(IPA_PACKET_INIT_DEST_ENDPOINT_FMASK)); */
493 
494 	cmd_payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
495 	payload = &cmd_payload->ip_packet_init;
496 
497 	payload->dest_endpoint = u8_encode_bits(endpoint_id,
498 					IPA_PACKET_INIT_DEST_ENDPOINT_FMASK);
499 
500 	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
501 			  direction, opcode);
502 }
503 
504 /* Use a DMA command to read or write a block of IPA-resident memory */
505 void ipa_cmd_dma_shared_mem_add(struct gsi_trans *trans, u32 offset, u16 size,
506 				dma_addr_t addr, bool toward_ipa)
507 {
508 	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
509 	enum ipa_cmd_opcode opcode = IPA_CMD_DMA_SHARED_MEM;
510 	struct ipa_cmd_hw_dma_mem_mem *payload;
511 	union ipa_cmd_payload *cmd_payload;
512 	enum dma_data_direction direction;
513 	dma_addr_t payload_addr;
514 	u16 flags;
515 
516 	/* size and offset must fit in 16 bit fields */
517 	/* assert(size > 0 && size <= U16_MAX); */
518 	/* assert(offset <= U16_MAX && ipa->mem_offset <= U16_MAX - offset); */
519 
520 	offset += ipa->mem_offset;
521 
522 	cmd_payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
523 	payload = &cmd_payload->dma_shared_mem;
524 
525 	/* payload->clear_after_read was reserved prior to IPA v4.0.  It's
526 	 * never needed for current code, so it's 0 regardless of version.
527 	 */
528 	payload->size = cpu_to_le16(size);
529 	payload->local_addr = cpu_to_le16(offset);
530 	/* payload->flags:
531 	 *   direction:		0 = write to IPA, 1 read from IPA
532 	 * Starting at v4.0 these are reserved; either way, all zero:
533 	 *   pipeline clear:	0 = wait for pipeline clear (don't skip)
534 	 *   clear_options:	0 = pipeline_clear_hps
535 	 * Instead, for v4.0+ these are encoded in the opcode.  But again
536 	 * since both values are 0 we won't bother OR'ing them in.
537 	 */
538 	flags = toward_ipa ? 0 : DMA_SHARED_MEM_FLAGS_DIRECTION_FMASK;
539 	payload->flags = cpu_to_le16(flags);
540 	payload->system_addr = cpu_to_le64(addr);
541 
542 	direction = toward_ipa ? DMA_TO_DEVICE : DMA_FROM_DEVICE;
543 
544 	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
545 			  direction, opcode);
546 }
547 
548 static void ipa_cmd_ip_tag_status_add(struct gsi_trans *trans)
549 {
550 	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
551 	enum ipa_cmd_opcode opcode = IPA_CMD_IP_PACKET_TAG_STATUS;
552 	enum dma_data_direction direction = DMA_TO_DEVICE;
553 	struct ipa_cmd_ip_packet_tag_status *payload;
554 	union ipa_cmd_payload *cmd_payload;
555 	dma_addr_t payload_addr;
556 
557 	/* assert(tag <= field_max(IP_PACKET_TAG_STATUS_TAG_FMASK)); */
558 
559 	cmd_payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
560 	payload = &cmd_payload->ip_packet_tag_status;
561 
562 	payload->tag = le64_encode_bits(0, IP_PACKET_TAG_STATUS_TAG_FMASK);
563 
564 	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
565 			  direction, opcode);
566 }
567 
568 /* Issue a small command TX data transfer */
569 static void ipa_cmd_transfer_add(struct gsi_trans *trans)
570 {
571 	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
572 	enum dma_data_direction direction = DMA_TO_DEVICE;
573 	enum ipa_cmd_opcode opcode = IPA_CMD_NONE;
574 	union ipa_cmd_payload *payload;
575 	dma_addr_t payload_addr;
576 
577 	/* Just transfer a zero-filled payload structure */
578 	payload = ipa_cmd_payload_alloc(ipa, &payload_addr);
579 
580 	gsi_trans_cmd_add(trans, payload, sizeof(*payload), payload_addr,
581 			  direction, opcode);
582 }
583 
584 /* Add immediate commands to a transaction to clear the hardware pipeline */
585 void ipa_cmd_pipeline_clear_add(struct gsi_trans *trans)
586 {
587 	struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi);
588 	struct ipa_endpoint *endpoint;
589 
590 	/* This will complete when the transfer is received */
591 	reinit_completion(&ipa->completion);
592 
593 	/* Issue a no-op register write command (mask 0 means no write) */
594 	ipa_cmd_register_write_add(trans, 0, 0, 0, true);
595 
596 	/* Send a data packet through the IPA pipeline.  The packet_init
597 	 * command says to send the next packet directly to the exception
598 	 * endpoint without any other IPA processing.  The tag_status
599 	 * command requests that status be generated on completion of
600 	 * that transfer, and that it will be tagged with a value.
601 	 * Finally, the transfer command sends a small packet of data
602 	 * (instead of a command) using the command endpoint.
603 	 */
604 	endpoint = ipa->name_map[IPA_ENDPOINT_AP_LAN_RX];
605 	ipa_cmd_ip_packet_init_add(trans, endpoint->endpoint_id);
606 	ipa_cmd_ip_tag_status_add(trans);
607 	ipa_cmd_transfer_add(trans);
608 }
609 
610 /* Returns the number of commands required to clear the pipeline */
611 u32 ipa_cmd_pipeline_clear_count(void)
612 {
613 	return 4;
614 }
615 
616 void ipa_cmd_pipeline_clear_wait(struct ipa *ipa)
617 {
618 	wait_for_completion(&ipa->completion);
619 }
620 
621 void ipa_cmd_pipeline_clear(struct ipa *ipa)
622 {
623 	u32 count = ipa_cmd_pipeline_clear_count();
624 	struct gsi_trans *trans;
625 
626 	trans = ipa_cmd_trans_alloc(ipa, count);
627 	if (trans) {
628 		ipa_cmd_pipeline_clear_add(trans);
629 		gsi_trans_commit_wait(trans);
630 		ipa_cmd_pipeline_clear_wait(ipa);
631 	} else {
632 		dev_err(&ipa->pdev->dev,
633 			"error allocating %u entry tag transaction\n", count);
634 	}
635 }
636 
637 static struct ipa_cmd_info *
638 ipa_cmd_info_alloc(struct ipa_endpoint *endpoint, u32 tre_count)
639 {
640 	struct gsi_channel *channel;
641 
642 	channel = &endpoint->ipa->gsi.channel[endpoint->channel_id];
643 
644 	return gsi_trans_pool_alloc(&channel->trans_info.info_pool, tre_count);
645 }
646 
647 /* Allocate a transaction for the command TX endpoint */
648 struct gsi_trans *ipa_cmd_trans_alloc(struct ipa *ipa, u32 tre_count)
649 {
650 	struct ipa_endpoint *endpoint;
651 	struct gsi_trans *trans;
652 
653 	endpoint = ipa->name_map[IPA_ENDPOINT_AP_COMMAND_TX];
654 
655 	trans = gsi_channel_trans_alloc(&ipa->gsi, endpoint->channel_id,
656 					tre_count, DMA_NONE);
657 	if (trans)
658 		trans->info = ipa_cmd_info_alloc(endpoint, tre_count);
659 
660 	return trans;
661 }
662