1// SPDX-License-Identifier: GPL-2.0
2
3/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
4 * Copyright (C) 2019-2020 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/if_rmnet.h>
12#include <linux/dma-direction.h>
13
14#include "gsi.h"
15#include "gsi_trans.h"
16#include "ipa.h"
17#include "ipa_data.h"
18#include "ipa_endpoint.h"
19#include "ipa_cmd.h"
20#include "ipa_mem.h"
21#include "ipa_modem.h"
22#include "ipa_table.h"
23#include "ipa_gsi.h"
24#include "ipa_clock.h"
25
26#define atomic_dec_not_zero(v)	atomic_add_unless((v), -1, 0)
27
28#define IPA_REPLENISH_BATCH	16
29
30/* RX buffer is 1 page (or a power-of-2 contiguous pages) */
31#define IPA_RX_BUFFER_SIZE	8192	/* PAGE_SIZE > 4096 wastes a LOT */
32
33/* The amount of RX buffer space consumed by standard skb overhead */
34#define IPA_RX_BUFFER_OVERHEAD	(PAGE_SIZE - SKB_MAX_ORDER(NET_SKB_PAD, 0))
35
36/* Where to find the QMAP mux_id for a packet within modem-supplied metadata */
37#define IPA_ENDPOINT_QMAP_METADATA_MASK		0x000000ff /* host byte order */
38
39#define IPA_ENDPOINT_RESET_AGGR_RETRY_MAX	3
40#define IPA_AGGR_TIME_LIMIT_DEFAULT		500	/* microseconds */
41
42/** enum ipa_status_opcode - status element opcode hardware values */
43enum ipa_status_opcode {
44	IPA_STATUS_OPCODE_PACKET		= 0x01,
45	IPA_STATUS_OPCODE_DROPPED_PACKET	= 0x04,
46	IPA_STATUS_OPCODE_SUSPENDED_PACKET	= 0x08,
47	IPA_STATUS_OPCODE_PACKET_2ND_PASS	= 0x40,
48};
49
50/** enum ipa_status_exception - status element exception type */
51enum ipa_status_exception {
52	/* 0 means no exception */
53	IPA_STATUS_EXCEPTION_DEAGGR		= 0x01,
54};
55
56/* Status element provided by hardware */
57struct ipa_status {
58	u8 opcode;		/* enum ipa_status_opcode */
59	u8 exception;		/* enum ipa_status_exception */
60	__le16 mask;
61	__le16 pkt_len;
62	u8 endp_src_idx;
63	u8 endp_dst_idx;
64	__le32 metadata;
65	__le32 flags1;
66	__le64 flags2;
67	__le32 flags3;
68	__le32 flags4;
69};
70
71/* Field masks for struct ipa_status structure fields */
72#define IPA_STATUS_DST_IDX_FMASK		GENMASK(4, 0)
73#define IPA_STATUS_FLAGS1_RT_RULE_ID_FMASK	GENMASK(31, 22)
74
75#ifdef IPA_VALIDATE
76
77static void ipa_endpoint_validate_build(void)
78{
79	/* The aggregation byte limit defines the point at which an
80	 * aggregation window will close.  It is programmed into the
81	 * IPA hardware as a number of KB.  We don't use "hard byte
82	 * limit" aggregation, which means that we need to supply
83	 * enough space in a receive buffer to hold a complete MTU
84	 * plus normal skb overhead *after* that aggregation byte
85	 * limit has been crossed.
86	 *
87	 * This check just ensures we don't define a receive buffer
88	 * size that would exceed what we can represent in the field
89	 * that is used to program its size.
90	 */
91	BUILD_BUG_ON(IPA_RX_BUFFER_SIZE >
92		     field_max(AGGR_BYTE_LIMIT_FMASK) * SZ_1K +
93		     IPA_MTU + IPA_RX_BUFFER_OVERHEAD);
94
95	/* I honestly don't know where this requirement comes from.  But
96	 * it holds, and if we someday need to loosen the constraint we
97	 * can try to track it down.
98	 */
99	BUILD_BUG_ON(sizeof(struct ipa_status) % 4);
100}
101
102static bool ipa_endpoint_data_valid_one(struct ipa *ipa, u32 count,
103			    const struct ipa_gsi_endpoint_data *all_data,
104			    const struct ipa_gsi_endpoint_data *data)
105{
106	const struct ipa_gsi_endpoint_data *other_data;
107	struct device *dev = &ipa->pdev->dev;
108	enum ipa_endpoint_name other_name;
109
110	if (ipa_gsi_endpoint_data_empty(data))
111		return true;
112
113	if (!data->toward_ipa) {
114		if (data->endpoint.filter_support) {
115			dev_err(dev, "filtering not supported for "
116					"RX endpoint %u\n",
117				data->endpoint_id);
118			return false;
119		}
120
121		return true;	/* Nothing more to check for RX */
122	}
123
124	if (data->endpoint.config.status_enable) {
125		other_name = data->endpoint.config.tx.status_endpoint;
126		if (other_name >= count) {
127			dev_err(dev, "status endpoint name %u out of range "
128					"for endpoint %u\n",
129				other_name, data->endpoint_id);
130			return false;
131		}
132
133		/* Status endpoint must be defined... */
134		other_data = &all_data[other_name];
135		if (ipa_gsi_endpoint_data_empty(other_data)) {
136			dev_err(dev, "DMA endpoint name %u undefined "
137					"for endpoint %u\n",
138				other_name, data->endpoint_id);
139			return false;
140		}
141
142		/* ...and has to be an RX endpoint... */
143		if (other_data->toward_ipa) {
144			dev_err(dev,
145				"status endpoint for endpoint %u not RX\n",
146				data->endpoint_id);
147			return false;
148		}
149
150		/* ...and if it's to be an AP endpoint... */
151		if (other_data->ee_id == GSI_EE_AP) {
152			/* ...make sure it has status enabled. */
153			if (!other_data->endpoint.config.status_enable) {
154				dev_err(dev,
155					"status not enabled for endpoint %u\n",
156					other_data->endpoint_id);
157				return false;
158			}
159		}
160	}
161
162	if (data->endpoint.config.dma_mode) {
163		other_name = data->endpoint.config.dma_endpoint;
164		if (other_name >= count) {
165			dev_err(dev, "DMA endpoint name %u out of range "
166					"for endpoint %u\n",
167				other_name, data->endpoint_id);
168			return false;
169		}
170
171		other_data = &all_data[other_name];
172		if (ipa_gsi_endpoint_data_empty(other_data)) {
173			dev_err(dev, "DMA endpoint name %u undefined "
174					"for endpoint %u\n",
175				other_name, data->endpoint_id);
176			return false;
177		}
178	}
179
180	return true;
181}
182
183static bool ipa_endpoint_data_valid(struct ipa *ipa, u32 count,
184				    const struct ipa_gsi_endpoint_data *data)
185{
186	const struct ipa_gsi_endpoint_data *dp = data;
187	struct device *dev = &ipa->pdev->dev;
188	enum ipa_endpoint_name name;
189
190	ipa_endpoint_validate_build();
191
192	if (count > IPA_ENDPOINT_COUNT) {
193		dev_err(dev, "too many endpoints specified (%u > %u)\n",
194			count, IPA_ENDPOINT_COUNT);
195		return false;
196	}
197
198	/* Make sure needed endpoints have defined data */
199	if (ipa_gsi_endpoint_data_empty(&data[IPA_ENDPOINT_AP_COMMAND_TX])) {
200		dev_err(dev, "command TX endpoint not defined\n");
201		return false;
202	}
203	if (ipa_gsi_endpoint_data_empty(&data[IPA_ENDPOINT_AP_LAN_RX])) {
204		dev_err(dev, "LAN RX endpoint not defined\n");
205		return false;
206	}
207	if (ipa_gsi_endpoint_data_empty(&data[IPA_ENDPOINT_AP_MODEM_TX])) {
208		dev_err(dev, "AP->modem TX endpoint not defined\n");
209		return false;
210	}
211	if (ipa_gsi_endpoint_data_empty(&data[IPA_ENDPOINT_AP_MODEM_RX])) {
212		dev_err(dev, "AP<-modem RX endpoint not defined\n");
213		return false;
214	}
215
216	for (name = 0; name < count; name++, dp++)
217		if (!ipa_endpoint_data_valid_one(ipa, count, data, dp))
218			return false;
219
220	return true;
221}
222
223#else /* !IPA_VALIDATE */
224
225static bool ipa_endpoint_data_valid(struct ipa *ipa, u32 count,
226				    const struct ipa_gsi_endpoint_data *data)
227{
228	return true;
229}
230
231#endif /* !IPA_VALIDATE */
232
233/* Allocate a transaction to use on a non-command endpoint */
234static struct gsi_trans *ipa_endpoint_trans_alloc(struct ipa_endpoint *endpoint,
235						  u32 tre_count)
236{
237	struct gsi *gsi = &endpoint->ipa->gsi;
238	u32 channel_id = endpoint->channel_id;
239	enum dma_data_direction direction;
240
241	direction = endpoint->toward_ipa ? DMA_TO_DEVICE : DMA_FROM_DEVICE;
242
243	return gsi_channel_trans_alloc(gsi, channel_id, tre_count, direction);
244}
245
246/* suspend_delay represents suspend for RX, delay for TX endpoints.
247 * Note that suspend is not supported starting with IPA v4.0.
248 */
249static bool
250ipa_endpoint_init_ctrl(struct ipa_endpoint *endpoint, bool suspend_delay)
251{
252	u32 offset = IPA_REG_ENDP_INIT_CTRL_N_OFFSET(endpoint->endpoint_id);
253	struct ipa *ipa = endpoint->ipa;
254	bool state;
255	u32 mask;
256	u32 val;
257
258	/* Suspend is not supported for IPA v4.0+.  Delay doesn't work
259	 * correctly on IPA v4.2.
260	 *
261	 * if (endpoint->toward_ipa)
262	 * 	assert(ipa->version != IPA_VERSION_4.2);
263	 * else
264	 * 	assert(ipa->version == IPA_VERSION_3_5_1);
265	 */
266	mask = endpoint->toward_ipa ? ENDP_DELAY_FMASK : ENDP_SUSPEND_FMASK;
267
268	val = ioread32(ipa->reg_virt + offset);
269	/* Don't bother if it's already in the requested state */
270	state = !!(val & mask);
271	if (suspend_delay != state) {
272		val ^= mask;
273		iowrite32(val, ipa->reg_virt + offset);
274	}
275
276	return state;
277}
278
279/* We currently don't care what the previous state was for delay mode */
280static void
281ipa_endpoint_program_delay(struct ipa_endpoint *endpoint, bool enable)
282{
283	/* assert(endpoint->toward_ipa); */
284
285	/* Delay mode doesn't work properly for IPA v4.2 */
286	if (endpoint->ipa->version != IPA_VERSION_4_2)
287		(void)ipa_endpoint_init_ctrl(endpoint, enable);
288}
289
290static bool ipa_endpoint_aggr_active(struct ipa_endpoint *endpoint)
291{
292	u32 mask = BIT(endpoint->endpoint_id);
293	struct ipa *ipa = endpoint->ipa;
294	u32 offset;
295	u32 val;
296
297	/* assert(mask & ipa->available); */
298	offset = ipa_reg_state_aggr_active_offset(ipa->version);
299	val = ioread32(ipa->reg_virt + offset);
300
301	return !!(val & mask);
302}
303
304static void ipa_endpoint_force_close(struct ipa_endpoint *endpoint)
305{
306	u32 mask = BIT(endpoint->endpoint_id);
307	struct ipa *ipa = endpoint->ipa;
308
309	/* assert(mask & ipa->available); */
310	iowrite32(mask, ipa->reg_virt + IPA_REG_AGGR_FORCE_CLOSE_OFFSET);
311}
312
313/**
314 * ipa_endpoint_suspend_aggr() - Emulate suspend interrupt
315 * @endpoint:	Endpoint on which to emulate a suspend
316 *
317 *  Emulate suspend IPA interrupt to unsuspend an endpoint suspended
318 *  with an open aggregation frame.  This is to work around a hardware
319 *  issue in IPA version 3.5.1 where the suspend interrupt will not be
320 *  generated when it should be.
321 */
322static void ipa_endpoint_suspend_aggr(struct ipa_endpoint *endpoint)
323{
324	struct ipa *ipa = endpoint->ipa;
325
326	if (!endpoint->data->aggregation)
327		return;
328
329	/* Nothing to do if the endpoint doesn't have aggregation open */
330	if (!ipa_endpoint_aggr_active(endpoint))
331		return;
332
333	/* Force close aggregation */
334	ipa_endpoint_force_close(endpoint);
335
336	ipa_interrupt_simulate_suspend(ipa->interrupt);
337}
338
339/* Returns previous suspend state (true means suspend was enabled) */
340static bool
341ipa_endpoint_program_suspend(struct ipa_endpoint *endpoint, bool enable)
342{
343	bool suspended;
344
345	if (endpoint->ipa->version != IPA_VERSION_3_5_1)
346		return enable;	/* For IPA v4.0+, no change made */
347
348	/* assert(!endpoint->toward_ipa); */
349
350	suspended = ipa_endpoint_init_ctrl(endpoint, enable);
351
352	/* A client suspended with an open aggregation frame will not
353	 * generate a SUSPEND IPA interrupt.  If enabling suspend, have
354	 * ipa_endpoint_suspend_aggr() handle this.
355	 */
356	if (enable && !suspended)
357		ipa_endpoint_suspend_aggr(endpoint);
358
359	return suspended;
360}
361
362/* Enable or disable delay or suspend mode on all modem endpoints */
363void ipa_endpoint_modem_pause_all(struct ipa *ipa, bool enable)
364{
365	u32 endpoint_id;
366
367	/* DELAY mode doesn't work correctly on IPA v4.2 */
368	if (ipa->version == IPA_VERSION_4_2)
369		return;
370
371	for (endpoint_id = 0; endpoint_id < IPA_ENDPOINT_MAX; endpoint_id++) {
372		struct ipa_endpoint *endpoint = &ipa->endpoint[endpoint_id];
373
374		if (endpoint->ee_id != GSI_EE_MODEM)
375			continue;
376
377		/* Set TX delay mode or RX suspend mode */
378		if (endpoint->toward_ipa)
379			ipa_endpoint_program_delay(endpoint, enable);
380		else
381			(void)ipa_endpoint_program_suspend(endpoint, enable);
382	}
383}
384
385/* Reset all modem endpoints to use the default exception endpoint */
386int ipa_endpoint_modem_exception_reset_all(struct ipa *ipa)
387{
388	u32 initialized = ipa->initialized;
389	struct gsi_trans *trans;
390	u32 count;
391
392	/* We need one command per modem TX endpoint.  We can get an upper
393	 * bound on that by assuming all initialized endpoints are modem->IPA.
394	 * That won't happen, and we could be more precise, but this is fine
395	 * for now.  We need to end the transaction with a "tag process."
396	 */
397	count = hweight32(initialized) + ipa_cmd_tag_process_count();
398	trans = ipa_cmd_trans_alloc(ipa, count);
399	if (!trans) {
400		dev_err(&ipa->pdev->dev,
401			"no transaction to reset modem exception endpoints\n");
402		return -EBUSY;
403	}
404
405	while (initialized) {
406		u32 endpoint_id = __ffs(initialized);
407		struct ipa_endpoint *endpoint;
408		u32 offset;
409
410		initialized ^= BIT(endpoint_id);
411
412		/* We only reset modem TX endpoints */
413		endpoint = &ipa->endpoint[endpoint_id];
414		if (!(endpoint->ee_id == GSI_EE_MODEM && endpoint->toward_ipa))
415			continue;
416
417		offset = IPA_REG_ENDP_STATUS_N_OFFSET(endpoint_id);
418
419		/* Value written is 0, and all bits are updated.  That
420		 * means status is disabled on the endpoint, and as a
421		 * result all other fields in the register are ignored.
422		 */
423		ipa_cmd_register_write_add(trans, offset, 0, ~0, false);
424	}
425
426	ipa_cmd_tag_process_add(trans);
427
428	/* XXX This should have a 1 second timeout */
429	gsi_trans_commit_wait(trans);
430
431	return 0;
432}
433
434static void ipa_endpoint_init_cfg(struct ipa_endpoint *endpoint)
435{
436	u32 offset = IPA_REG_ENDP_INIT_CFG_N_OFFSET(endpoint->endpoint_id);
437	u32 val = 0;
438
439	/* FRAG_OFFLOAD_EN is 0 */
440	if (endpoint->data->checksum) {
441		if (endpoint->toward_ipa) {
442			u32 checksum_offset;
443
444			val |= u32_encode_bits(IPA_CS_OFFLOAD_UL,
445					       CS_OFFLOAD_EN_FMASK);
446			/* Checksum header offset is in 4-byte units */
447			checksum_offset = sizeof(struct rmnet_map_header);
448			checksum_offset /= sizeof(u32);
449			val |= u32_encode_bits(checksum_offset,
450					       CS_METADATA_HDR_OFFSET_FMASK);
451		} else {
452			val |= u32_encode_bits(IPA_CS_OFFLOAD_DL,
453					       CS_OFFLOAD_EN_FMASK);
454		}
455	} else {
456		val |= u32_encode_bits(IPA_CS_OFFLOAD_NONE,
457				       CS_OFFLOAD_EN_FMASK);
458	}
459	/* CS_GEN_QMB_MASTER_SEL is 0 */
460
461	iowrite32(val, endpoint->ipa->reg_virt + offset);
462}
463
464/**
465 * ipa_endpoint_init_hdr() - Initialize HDR endpoint configuration register
466 * @endpoint:	Endpoint pointer
467 *
468 * We program QMAP endpoints so each packet received is preceded by a QMAP
469 * header structure.  The QMAP header contains a 1-byte mux_id and 2-byte
470 * packet size field, and we have the IPA hardware populate both for each
471 * received packet.  The header is configured (in the HDR_EXT register)
472 * to use big endian format.
473 *
474 * The packet size is written into the QMAP header's pkt_len field.  That
475 * location is defined here using the HDR_OFST_PKT_SIZE field.
476 *
477 * The mux_id comes from a 4-byte metadata value supplied with each packet
478 * by the modem.  It is *not* a QMAP header, but it does contain the mux_id
479 * value that we want, in its low-order byte.  A bitmask defined in the
480 * endpoint's METADATA_MASK register defines which byte within the modem
481 * metadata contains the mux_id.  And the OFST_METADATA field programmed
482 * here indicates where the extracted byte should be placed within the QMAP
483 * header.
484 */
485static void ipa_endpoint_init_hdr(struct ipa_endpoint *endpoint)
486{
487	u32 offset = IPA_REG_ENDP_INIT_HDR_N_OFFSET(endpoint->endpoint_id);
488	u32 val = 0;
489
490	if (endpoint->data->qmap) {
491		size_t header_size = sizeof(struct rmnet_map_header);
492
493		/* We might supply a checksum header after the QMAP header */
494		if (endpoint->toward_ipa && endpoint->data->checksum)
495			header_size += sizeof(struct rmnet_map_ul_csum_header);
496		val |= u32_encode_bits(header_size, HDR_LEN_FMASK);
497
498		/* Define how to fill fields in a received QMAP header */
499		if (!endpoint->toward_ipa) {
500			u32 off;	/* Field offset within header */
501
502			/* Where IPA will write the metadata value */
503			off = offsetof(struct rmnet_map_header, mux_id);
504			val |= u32_encode_bits(off, HDR_OFST_METADATA_FMASK);
505
506			/* Where IPA will write the length */
507			off = offsetof(struct rmnet_map_header, pkt_len);
508			val |= HDR_OFST_PKT_SIZE_VALID_FMASK;
509			val |= u32_encode_bits(off, HDR_OFST_PKT_SIZE_FMASK);
510		}
511		/* For QMAP TX, metadata offset is 0 (modem assumes this) */
512		val |= HDR_OFST_METADATA_VALID_FMASK;
513
514		/* HDR_ADDITIONAL_CONST_LEN is 0; (RX only) */
515		/* HDR_A5_MUX is 0 */
516		/* HDR_LEN_INC_DEAGG_HDR is 0 */
517		/* HDR_METADATA_REG_VALID is 0 (TX only) */
518	}
519
520	iowrite32(val, endpoint->ipa->reg_virt + offset);
521}
522
523static void ipa_endpoint_init_hdr_ext(struct ipa_endpoint *endpoint)
524{
525	u32 offset = IPA_REG_ENDP_INIT_HDR_EXT_N_OFFSET(endpoint->endpoint_id);
526	u32 pad_align = endpoint->data->rx.pad_align;
527	u32 val = 0;
528
529	val |= HDR_ENDIANNESS_FMASK;		/* big endian */
530
531	/* A QMAP header contains a 6 bit pad field at offset 0.  The RMNet
532	 * driver assumes this field is meaningful in packets it receives,
533	 * and assumes the header's payload length includes that padding.
534	 * The RMNet driver does *not* pad packets it sends, however, so
535	 * the pad field (although 0) should be ignored.
536	 */
537	if (endpoint->data->qmap && !endpoint->toward_ipa) {
538		val |= HDR_TOTAL_LEN_OR_PAD_VALID_FMASK;
539		/* HDR_TOTAL_LEN_OR_PAD is 0 (pad, not total_len) */
540		val |= HDR_PAYLOAD_LEN_INC_PADDING_FMASK;
541		/* HDR_TOTAL_LEN_OR_PAD_OFFSET is 0 */
542	}
543
544	/* HDR_PAYLOAD_LEN_INC_PADDING is 0 */
545	if (!endpoint->toward_ipa)
546		val |= u32_encode_bits(pad_align, HDR_PAD_TO_ALIGNMENT_FMASK);
547
548	iowrite32(val, endpoint->ipa->reg_virt + offset);
549}
550
551
552static void ipa_endpoint_init_hdr_metadata_mask(struct ipa_endpoint *endpoint)
553{
554	u32 endpoint_id = endpoint->endpoint_id;
555	u32 val = 0;
556	u32 offset;
557
558	if (endpoint->toward_ipa)
559		return;		/* Register not valid for TX endpoints */
560
561	offset = IPA_REG_ENDP_INIT_HDR_METADATA_MASK_N_OFFSET(endpoint_id);
562
563	/* Note that HDR_ENDIANNESS indicates big endian header fields */
564	if (endpoint->data->qmap)
565		val = cpu_to_be32(IPA_ENDPOINT_QMAP_METADATA_MASK);
566
567	iowrite32(val, endpoint->ipa->reg_virt + offset);
568}
569
570static void ipa_endpoint_init_mode(struct ipa_endpoint *endpoint)
571{
572	u32 offset = IPA_REG_ENDP_INIT_MODE_N_OFFSET(endpoint->endpoint_id);
573	u32 val;
574
575	if (!endpoint->toward_ipa)
576		return;		/* Register not valid for RX endpoints */
577
578	if (endpoint->data->dma_mode) {
579		enum ipa_endpoint_name name = endpoint->data->dma_endpoint;
580		u32 dma_endpoint_id;
581
582		dma_endpoint_id = endpoint->ipa->name_map[name]->endpoint_id;
583
584		val = u32_encode_bits(IPA_DMA, MODE_FMASK);
585		val |= u32_encode_bits(dma_endpoint_id, DEST_PIPE_INDEX_FMASK);
586	} else {
587		val = u32_encode_bits(IPA_BASIC, MODE_FMASK);
588	}
589	/* All other bits unspecified (and 0) */
590
591	iowrite32(val, endpoint->ipa->reg_virt + offset);
592}
593
594/* Compute the aggregation size value to use for a given buffer size */
595static u32 ipa_aggr_size_kb(u32 rx_buffer_size)
596{
597	/* We don't use "hard byte limit" aggregation, so we define the
598	 * aggregation limit such that our buffer has enough space *after*
599	 * that limit to receive a full MTU of data, plus overhead.
600	 */
601	rx_buffer_size -= IPA_MTU + IPA_RX_BUFFER_OVERHEAD;
602
603	return rx_buffer_size / SZ_1K;
604}
605
606static void ipa_endpoint_init_aggr(struct ipa_endpoint *endpoint)
607{
608	u32 offset = IPA_REG_ENDP_INIT_AGGR_N_OFFSET(endpoint->endpoint_id);
609	u32 val = 0;
610
611	if (endpoint->data->aggregation) {
612		if (!endpoint->toward_ipa) {
613			u32 buffer_size;
614			u32 limit;
615
616			val |= u32_encode_bits(IPA_ENABLE_AGGR, AGGR_EN_FMASK);
617			val |= u32_encode_bits(IPA_GENERIC, AGGR_TYPE_FMASK);
618
619			buffer_size = IPA_RX_BUFFER_SIZE - NET_SKB_PAD;
620			limit = ipa_aggr_size_kb(buffer_size);
621			val |= u32_encode_bits(limit, AGGR_BYTE_LIMIT_FMASK);
622
623			limit = IPA_AGGR_TIME_LIMIT_DEFAULT;
624			limit = DIV_ROUND_CLOSEST(limit, IPA_AGGR_GRANULARITY);
625			val |= u32_encode_bits(limit, AGGR_TIME_LIMIT_FMASK);
626
627			/* AGGR_PKT_LIMIT is 0 (unlimited) */
628
629			if (endpoint->data->rx.aggr_close_eof)
630				val |= AGGR_SW_EOF_ACTIVE_FMASK;
631			/* AGGR_HARD_BYTE_LIMIT_ENABLE is 0 */
632		} else {
633			val |= u32_encode_bits(IPA_ENABLE_DEAGGR,
634					       AGGR_EN_FMASK);
635			val |= u32_encode_bits(IPA_QCMAP, AGGR_TYPE_FMASK);
636			/* other fields ignored */
637		}
638		/* AGGR_FORCE_CLOSE is 0 */
639	} else {
640		val |= u32_encode_bits(IPA_BYPASS_AGGR, AGGR_EN_FMASK);
641		/* other fields ignored */
642	}
643
644	iowrite32(val, endpoint->ipa->reg_virt + offset);
645}
646
647/* The head-of-line blocking timer is defined as a tick count, where each
648 * tick represents 128 cycles of the IPA core clock.  Return the value
649 * that should be written to that register that represents the timeout
650 * period provided.
651 */
652static u32 ipa_reg_init_hol_block_timer_val(struct ipa *ipa, u32 microseconds)
653{
654	u32 width;
655	u32 scale;
656	u64 ticks;
657	u64 rate;
658	u32 high;
659	u32 val;
660
661	if (!microseconds)
662		return 0;	/* Nothing to compute if timer period is 0 */
663
664	/* Use 64 bit arithmetic to avoid overflow... */
665	rate = ipa_clock_rate(ipa);
666	ticks = DIV_ROUND_CLOSEST(microseconds * rate, 128 * USEC_PER_SEC);
667	/* ...but we still need to fit into a 32-bit register */
668	WARN_ON(ticks > U32_MAX);
669
670	/* IPA v3.5.1 just records the tick count */
671	if (ipa->version == IPA_VERSION_3_5_1)
672		return (u32)ticks;
673
674	/* For IPA v4.2, the tick count is represented by base and
675	 * scale fields within the 32-bit timer register, where:
676	 *     ticks = base << scale;
677	 * The best precision is achieved when the base value is as
678	 * large as possible.  Find the highest set bit in the tick
679	 * count, and extract the number of bits in the base field
680	 * such that that high bit is included.
681	 */
682	high = fls(ticks);		/* 1..32 */
683	width = HWEIGHT32(BASE_VALUE_FMASK);
684	scale = high > width ? high - width : 0;
685	if (scale) {
686		/* If we're scaling, round up to get a closer result */
687		ticks += 1 << (scale - 1);
688		/* High bit was set, so rounding might have affected it */
689		if (fls(ticks) != high)
690			scale++;
691	}
692
693	val = u32_encode_bits(scale, SCALE_FMASK);
694	val |= u32_encode_bits(ticks >> scale, BASE_VALUE_FMASK);
695
696	return val;
697}
698
699/* If microseconds is 0, timeout is immediate */
700static void ipa_endpoint_init_hol_block_timer(struct ipa_endpoint *endpoint,
701					      u32 microseconds)
702{
703	u32 endpoint_id = endpoint->endpoint_id;
704	struct ipa *ipa = endpoint->ipa;
705	u32 offset;
706	u32 val;
707
708	/* This should only be changed when HOL_BLOCK_EN is disabled */
709	offset = IPA_REG_ENDP_INIT_HOL_BLOCK_TIMER_N_OFFSET(endpoint_id);
710	val = ipa_reg_init_hol_block_timer_val(ipa, microseconds);
711	iowrite32(val, ipa->reg_virt + offset);
712}
713
714static void
715ipa_endpoint_init_hol_block_enable(struct ipa_endpoint *endpoint, bool enable)
716{
717	u32 endpoint_id = endpoint->endpoint_id;
718	u32 offset;
719	u32 val;
720
721	val = enable ? HOL_BLOCK_EN_FMASK : 0;
722	offset = IPA_REG_ENDP_INIT_HOL_BLOCK_EN_N_OFFSET(endpoint_id);
723	iowrite32(val, endpoint->ipa->reg_virt + offset);
724}
725
726void ipa_endpoint_modem_hol_block_clear_all(struct ipa *ipa)
727{
728	u32 i;
729
730	for (i = 0; i < IPA_ENDPOINT_MAX; i++) {
731		struct ipa_endpoint *endpoint = &ipa->endpoint[i];
732
733		if (endpoint->toward_ipa || endpoint->ee_id != GSI_EE_MODEM)
734			continue;
735
736		ipa_endpoint_init_hol_block_enable(endpoint, false);
737		ipa_endpoint_init_hol_block_timer(endpoint, 0);
738		ipa_endpoint_init_hol_block_enable(endpoint, true);
739	}
740}
741
742static void ipa_endpoint_init_deaggr(struct ipa_endpoint *endpoint)
743{
744	u32 offset = IPA_REG_ENDP_INIT_DEAGGR_N_OFFSET(endpoint->endpoint_id);
745	u32 val = 0;
746
747	if (!endpoint->toward_ipa)
748		return;		/* Register not valid for RX endpoints */
749
750	/* DEAGGR_HDR_LEN is 0 */
751	/* PACKET_OFFSET_VALID is 0 */
752	/* PACKET_OFFSET_LOCATION is ignored (not valid) */
753	/* MAX_PACKET_LEN is 0 (not enforced) */
754
755	iowrite32(val, endpoint->ipa->reg_virt + offset);
756}
757
758static void ipa_endpoint_init_seq(struct ipa_endpoint *endpoint)
759{
760	u32 offset = IPA_REG_ENDP_INIT_SEQ_N_OFFSET(endpoint->endpoint_id);
761	u32 seq_type = endpoint->seq_type;
762	u32 val = 0;
763
764	if (!endpoint->toward_ipa)
765		return;		/* Register not valid for RX endpoints */
766
767	/* Sequencer type is made up of four nibbles */
768	val |= u32_encode_bits(seq_type & 0xf, HPS_SEQ_TYPE_FMASK);
769	val |= u32_encode_bits((seq_type >> 4) & 0xf, DPS_SEQ_TYPE_FMASK);
770	/* The second two apply to replicated packets */
771	val |= u32_encode_bits((seq_type >> 8) & 0xf, HPS_REP_SEQ_TYPE_FMASK);
772	val |= u32_encode_bits((seq_type >> 12) & 0xf, DPS_REP_SEQ_TYPE_FMASK);
773
774	iowrite32(val, endpoint->ipa->reg_virt + offset);
775}
776
777/**
778 * ipa_endpoint_skb_tx() - Transmit a socket buffer
779 * @endpoint:	Endpoint pointer
780 * @skb:	Socket buffer to send
781 *
782 * Returns:	0 if successful, or a negative error code
783 */
784int ipa_endpoint_skb_tx(struct ipa_endpoint *endpoint, struct sk_buff *skb)
785{
786	struct gsi_trans *trans;
787	u32 nr_frags;
788	int ret;
789
790	/* Make sure source endpoint's TLV FIFO has enough entries to
791	 * hold the linear portion of the skb and all its fragments.
792	 * If not, see if we can linearize it before giving up.
793	 */
794	nr_frags = skb_shinfo(skb)->nr_frags;
795	if (1 + nr_frags > endpoint->trans_tre_max) {
796		if (skb_linearize(skb))
797			return -E2BIG;
798		nr_frags = 0;
799	}
800
801	trans = ipa_endpoint_trans_alloc(endpoint, 1 + nr_frags);
802	if (!trans)
803		return -EBUSY;
804
805	ret = gsi_trans_skb_add(trans, skb);
806	if (ret)
807		goto err_trans_free;
808	trans->data = skb;	/* transaction owns skb now */
809
810	gsi_trans_commit(trans, !netdev_xmit_more());
811
812	return 0;
813
814err_trans_free:
815	gsi_trans_free(trans);
816
817	return -ENOMEM;
818}
819
820static void ipa_endpoint_status(struct ipa_endpoint *endpoint)
821{
822	u32 endpoint_id = endpoint->endpoint_id;
823	struct ipa *ipa = endpoint->ipa;
824	u32 val = 0;
825	u32 offset;
826
827	offset = IPA_REG_ENDP_STATUS_N_OFFSET(endpoint_id);
828
829	if (endpoint->data->status_enable) {
830		val |= STATUS_EN_FMASK;
831		if (endpoint->toward_ipa) {
832			enum ipa_endpoint_name name;
833			u32 status_endpoint_id;
834
835			name = endpoint->data->tx.status_endpoint;
836			status_endpoint_id = ipa->name_map[name]->endpoint_id;
837
838			val |= u32_encode_bits(status_endpoint_id,
839					       STATUS_ENDP_FMASK);
840		}
841		/* STATUS_LOCATION is 0 (status element precedes packet) */
842		/* The next field is present for IPA v4.0 and above */
843		/* STATUS_PKT_SUPPRESS_FMASK is 0 */
844	}
845
846	iowrite32(val, ipa->reg_virt + offset);
847}
848
849static int ipa_endpoint_replenish_one(struct ipa_endpoint *endpoint)
850{
851	struct gsi_trans *trans;
852	bool doorbell = false;
853	struct page *page;
854	u32 offset;
855	u32 len;
856	int ret;
857
858	page = dev_alloc_pages(get_order(IPA_RX_BUFFER_SIZE));
859	if (!page)
860		return -ENOMEM;
861
862	trans = ipa_endpoint_trans_alloc(endpoint, 1);
863	if (!trans)
864		goto err_free_pages;
865
866	/* Offset the buffer to make space for skb headroom */
867	offset = NET_SKB_PAD;
868	len = IPA_RX_BUFFER_SIZE - offset;
869
870	ret = gsi_trans_page_add(trans, page, len, offset);
871	if (ret)
872		goto err_trans_free;
873	trans->data = page;	/* transaction owns page now */
874
875	if (++endpoint->replenish_ready == IPA_REPLENISH_BATCH) {
876		doorbell = true;
877		endpoint->replenish_ready = 0;
878	}
879
880	gsi_trans_commit(trans, doorbell);
881
882	return 0;
883
884err_trans_free:
885	gsi_trans_free(trans);
886err_free_pages:
887	put_page(page);
888
889	return -ENOMEM;
890}
891
892/**
893 * ipa_endpoint_replenish() - Replenish the Rx packets cache.
894 * @endpoint:	Endpoint to be replenished
895 * @count:	Number of buffers to send to hardware
896 *
897 * Allocate RX packet wrapper structures with maximal socket buffers
898 * for an endpoint.  These are supplied to the hardware, which fills
899 * them with incoming data.
900 */
901static void ipa_endpoint_replenish(struct ipa_endpoint *endpoint, u32 count)
902{
903	struct gsi *gsi;
904	u32 backlog;
905
906	if (!test_bit(IPA_REPLENISH_ENABLED, endpoint->replenish_flags)) {
907		if (count)
908			atomic_add(count, &endpoint->replenish_saved);
909		return;
910	}
911
912	/* If already active, just update the backlog */
913	if (test_and_set_bit(IPA_REPLENISH_ACTIVE, endpoint->replenish_flags)) {
914		if (count)
915			atomic_add(count, &endpoint->replenish_backlog);
916		return;
917	}
918
919	while (atomic_dec_not_zero(&endpoint->replenish_backlog))
920		if (ipa_endpoint_replenish_one(endpoint))
921			goto try_again_later;
922
923	clear_bit(IPA_REPLENISH_ACTIVE, endpoint->replenish_flags);
924
925	if (count)
926		atomic_add(count, &endpoint->replenish_backlog);
927
928	return;
929
930try_again_later:
931	clear_bit(IPA_REPLENISH_ACTIVE, endpoint->replenish_flags);
932
933	/* The last one didn't succeed, so fix the backlog */
934	backlog = atomic_add_return(count + 1, &endpoint->replenish_backlog);
935
936	/* Whenever a receive buffer transaction completes we'll try to
937	 * replenish again.  It's unlikely, but if we fail to supply even
938	 * one buffer, nothing will trigger another replenish attempt.
939	 * Receive buffer transactions use one TRE, so schedule work to
940	 * try replenishing again if our backlog is *all* available TREs.
941	 */
942	gsi = &endpoint->ipa->gsi;
943	if (backlog == gsi_channel_tre_max(gsi, endpoint->channel_id))
944		schedule_delayed_work(&endpoint->replenish_work,
945				      msecs_to_jiffies(1));
946}
947
948static void ipa_endpoint_replenish_enable(struct ipa_endpoint *endpoint)
949{
950	struct gsi *gsi = &endpoint->ipa->gsi;
951	u32 max_backlog;
952	u32 saved;
953
954	set_bit(IPA_REPLENISH_ENABLED, endpoint->replenish_flags);
955	while ((saved = atomic_xchg(&endpoint->replenish_saved, 0)))
956		atomic_add(saved, &endpoint->replenish_backlog);
957
958	/* Start replenishing if hardware currently has no buffers */
959	max_backlog = gsi_channel_tre_max(gsi, endpoint->channel_id);
960	if (atomic_read(&endpoint->replenish_backlog) == max_backlog)
961		ipa_endpoint_replenish(endpoint, 0);
962}
963
964static void ipa_endpoint_replenish_disable(struct ipa_endpoint *endpoint)
965{
966	u32 backlog;
967
968	clear_bit(IPA_REPLENISH_ENABLED, endpoint->replenish_flags);
969	while ((backlog = atomic_xchg(&endpoint->replenish_backlog, 0)))
970		atomic_add(backlog, &endpoint->replenish_saved);
971}
972
973static void ipa_endpoint_replenish_work(struct work_struct *work)
974{
975	struct delayed_work *dwork = to_delayed_work(work);
976	struct ipa_endpoint *endpoint;
977
978	endpoint = container_of(dwork, struct ipa_endpoint, replenish_work);
979
980	ipa_endpoint_replenish(endpoint, 0);
981}
982
983static void ipa_endpoint_skb_copy(struct ipa_endpoint *endpoint,
984				  void *data, u32 len, u32 extra)
985{
986	struct sk_buff *skb;
987
988	skb = __dev_alloc_skb(len, GFP_ATOMIC);
989	if (skb) {
990		skb_put(skb, len);
991		memcpy(skb->data, data, len);
992		skb->truesize += extra;
993	}
994
995	/* Now receive it, or drop it if there's no netdev */
996	if (endpoint->netdev)
997		ipa_modem_skb_rx(endpoint->netdev, skb);
998	else if (skb)
999		dev_kfree_skb_any(skb);
1000}
1001
1002static bool ipa_endpoint_skb_build(struct ipa_endpoint *endpoint,
1003				   struct page *page, u32 len)
1004{
1005	struct sk_buff *skb;
1006
1007	/* Nothing to do if there's no netdev */
1008	if (!endpoint->netdev)
1009		return false;
1010
1011	/* assert(len <= SKB_WITH_OVERHEAD(IPA_RX_BUFFER_SIZE-NET_SKB_PAD)); */
1012	skb = build_skb(page_address(page), IPA_RX_BUFFER_SIZE);
1013	if (skb) {
1014		/* Reserve the headroom and account for the data */
1015		skb_reserve(skb, NET_SKB_PAD);
1016		skb_put(skb, len);
1017	}
1018
1019	/* Receive the buffer (or record drop if unable to build it) */
1020	ipa_modem_skb_rx(endpoint->netdev, skb);
1021
1022	return skb != NULL;
1023}
1024
1025/* The format of a packet status element is the same for several status
1026 * types (opcodes).  Other types aren't currently supported.
1027 */
1028static bool ipa_status_format_packet(enum ipa_status_opcode opcode)
1029{
1030	switch (opcode) {
1031	case IPA_STATUS_OPCODE_PACKET:
1032	case IPA_STATUS_OPCODE_DROPPED_PACKET:
1033	case IPA_STATUS_OPCODE_SUSPENDED_PACKET:
1034	case IPA_STATUS_OPCODE_PACKET_2ND_PASS:
1035		return true;
1036	default:
1037		return false;
1038	}
1039}
1040
1041static bool ipa_endpoint_status_skip(struct ipa_endpoint *endpoint,
1042				     const struct ipa_status *status)
1043{
1044	u32 endpoint_id;
1045
1046	if (!ipa_status_format_packet(status->opcode))
1047		return true;
1048	if (!status->pkt_len)
1049		return true;
1050	endpoint_id = u32_get_bits(status->endp_dst_idx,
1051				   IPA_STATUS_DST_IDX_FMASK);
1052	if (endpoint_id != endpoint->endpoint_id)
1053		return true;
1054
1055	return false;	/* Don't skip this packet, process it */
1056}
1057
1058/* Return whether the status indicates the packet should be dropped */
1059static bool ipa_status_drop_packet(const struct ipa_status *status)
1060{
1061	u32 val;
1062
1063	/* Deaggregation exceptions we drop; all other types we consume */
1064	if (status->exception)
1065		return status->exception == IPA_STATUS_EXCEPTION_DEAGGR;
1066
1067	/* Drop the packet if it fails to match a routing rule; otherwise no */
1068	val = le32_get_bits(status->flags1, IPA_STATUS_FLAGS1_RT_RULE_ID_FMASK);
1069
1070	return val == field_max(IPA_STATUS_FLAGS1_RT_RULE_ID_FMASK);
1071}
1072
1073static void ipa_endpoint_status_parse(struct ipa_endpoint *endpoint,
1074				      struct page *page, u32 total_len)
1075{
1076	void *data = page_address(page) + NET_SKB_PAD;
1077	u32 unused = IPA_RX_BUFFER_SIZE - total_len;
1078	u32 resid = total_len;
1079
1080	while (resid) {
1081		const struct ipa_status *status = data;
1082		u32 align;
1083		u32 len;
1084
1085		if (resid < sizeof(*status)) {
1086			dev_err(&endpoint->ipa->pdev->dev,
1087				"short message (%u bytes < %zu byte status)\n",
1088				resid, sizeof(*status));
1089			break;
1090		}
1091
1092		/* Skip over status packets that lack packet data */
1093		if (ipa_endpoint_status_skip(endpoint, status)) {
1094			data += sizeof(*status);
1095			resid -= sizeof(*status);
1096			continue;
1097		}
1098
1099		/* Compute the amount of buffer space consumed by the
1100		 * packet, including the status element.  If the hardware
1101		 * is configured to pad packet data to an aligned boundary,
1102		 * account for that.  And if checksum offload is is enabled
1103		 * a trailer containing computed checksum information will
1104		 * be appended.
1105		 */
1106		align = endpoint->data->rx.pad_align ? : 1;
1107		len = le16_to_cpu(status->pkt_len);
1108		len = sizeof(*status) + ALIGN(len, align);
1109		if (endpoint->data->checksum)
1110			len += sizeof(struct rmnet_map_dl_csum_trailer);
1111
1112		/* Charge the new packet with a proportional fraction of
1113		 * the unused space in the original receive buffer.
1114		 * XXX Charge a proportion of the *whole* receive buffer?
1115		 */
1116		if (!ipa_status_drop_packet(status)) {
1117			u32 extra = unused * len / total_len;
1118			void *data2 = data + sizeof(*status);
1119			u32 len2 = le16_to_cpu(status->pkt_len);
1120
1121			/* Client receives only packet data (no status) */
1122			ipa_endpoint_skb_copy(endpoint, data2, len2, extra);
1123		}
1124
1125		/* Consume status and the full packet it describes */
1126		data += len;
1127		resid -= len;
1128	}
1129}
1130
1131/* Complete a TX transaction, command or from ipa_endpoint_skb_tx() */
1132static void ipa_endpoint_tx_complete(struct ipa_endpoint *endpoint,
1133				     struct gsi_trans *trans)
1134{
1135}
1136
1137/* Complete transaction initiated in ipa_endpoint_replenish_one() */
1138static void ipa_endpoint_rx_complete(struct ipa_endpoint *endpoint,
1139				     struct gsi_trans *trans)
1140{
1141	struct page *page;
1142
1143	ipa_endpoint_replenish(endpoint, 1);
1144
1145	if (trans->cancelled)
1146		return;
1147
1148	/* Parse or build a socket buffer using the actual received length */
1149	page = trans->data;
1150	if (endpoint->data->status_enable)
1151		ipa_endpoint_status_parse(endpoint, page, trans->len);
1152	else if (ipa_endpoint_skb_build(endpoint, page, trans->len))
1153		trans->data = NULL;	/* Pages have been consumed */
1154}
1155
1156void ipa_endpoint_trans_complete(struct ipa_endpoint *endpoint,
1157				 struct gsi_trans *trans)
1158{
1159	if (endpoint->toward_ipa)
1160		ipa_endpoint_tx_complete(endpoint, trans);
1161	else
1162		ipa_endpoint_rx_complete(endpoint, trans);
1163}
1164
1165void ipa_endpoint_trans_release(struct ipa_endpoint *endpoint,
1166				struct gsi_trans *trans)
1167{
1168	if (endpoint->toward_ipa) {
1169		struct ipa *ipa = endpoint->ipa;
1170
1171		/* Nothing to do for command transactions */
1172		if (endpoint != ipa->name_map[IPA_ENDPOINT_AP_COMMAND_TX]) {
1173			struct sk_buff *skb = trans->data;
1174
1175			if (skb)
1176				dev_kfree_skb_any(skb);
1177		}
1178	} else {
1179		struct page *page = trans->data;
1180
1181		if (page)
1182			put_page(page);
1183	}
1184}
1185
1186void ipa_endpoint_default_route_set(struct ipa *ipa, u32 endpoint_id)
1187{
1188	u32 val;
1189
1190	/* ROUTE_DIS is 0 */
1191	val = u32_encode_bits(endpoint_id, ROUTE_DEF_PIPE_FMASK);
1192	val |= ROUTE_DEF_HDR_TABLE_FMASK;
1193	val |= u32_encode_bits(0, ROUTE_DEF_HDR_OFST_FMASK);
1194	val |= u32_encode_bits(endpoint_id, ROUTE_FRAG_DEF_PIPE_FMASK);
1195	val |= ROUTE_DEF_RETAIN_HDR_FMASK;
1196
1197	iowrite32(val, ipa->reg_virt + IPA_REG_ROUTE_OFFSET);
1198}
1199
1200void ipa_endpoint_default_route_clear(struct ipa *ipa)
1201{
1202	ipa_endpoint_default_route_set(ipa, 0);
1203}
1204
1205/**
1206 * ipa_endpoint_reset_rx_aggr() - Reset RX endpoint with aggregation active
1207 * @endpoint:	Endpoint to be reset
1208 *
1209 * If aggregation is active on an RX endpoint when a reset is performed
1210 * on its underlying GSI channel, a special sequence of actions must be
1211 * taken to ensure the IPA pipeline is properly cleared.
1212 *
1213 * Return:	0 if successful, or a negative error code
1214 */
1215static int ipa_endpoint_reset_rx_aggr(struct ipa_endpoint *endpoint)
1216{
1217	struct device *dev = &endpoint->ipa->pdev->dev;
1218	struct ipa *ipa = endpoint->ipa;
1219	struct gsi *gsi = &ipa->gsi;
1220	bool suspended = false;
1221	dma_addr_t addr;
1222	bool legacy;
1223	u32 retries;
1224	u32 len = 1;
1225	void *virt;
1226	int ret;
1227
1228	virt = kzalloc(len, GFP_KERNEL);
1229	if (!virt)
1230		return -ENOMEM;
1231
1232	addr = dma_map_single(dev, virt, len, DMA_FROM_DEVICE);
1233	if (dma_mapping_error(dev, addr)) {
1234		ret = -ENOMEM;
1235		goto out_kfree;
1236	}
1237
1238	/* Force close aggregation before issuing the reset */
1239	ipa_endpoint_force_close(endpoint);
1240
1241	/* Reset and reconfigure the channel with the doorbell engine
1242	 * disabled.  Then poll until we know aggregation is no longer
1243	 * active.  We'll re-enable the doorbell (if appropriate) when
1244	 * we reset again below.
1245	 */
1246	gsi_channel_reset(gsi, endpoint->channel_id, false);
1247
1248	/* Make sure the channel isn't suspended */
1249	suspended = ipa_endpoint_program_suspend(endpoint, false);
1250
1251	/* Start channel and do a 1 byte read */
1252	ret = gsi_channel_start(gsi, endpoint->channel_id);
1253	if (ret)
1254		goto out_suspend_again;
1255
1256	ret = gsi_trans_read_byte(gsi, endpoint->channel_id, addr);
1257	if (ret)
1258		goto err_endpoint_stop;
1259
1260	/* Wait for aggregation to be closed on the channel */
1261	retries = IPA_ENDPOINT_RESET_AGGR_RETRY_MAX;
1262	do {
1263		if (!ipa_endpoint_aggr_active(endpoint))
1264			break;
1265		msleep(1);
1266	} while (retries--);
1267
1268	/* Check one last time */
1269	if (ipa_endpoint_aggr_active(endpoint))
1270		dev_err(dev, "endpoint %u still active during reset\n",
1271			endpoint->endpoint_id);
1272
1273	gsi_trans_read_byte_done(gsi, endpoint->channel_id);
1274
1275	ret = gsi_channel_stop(gsi, endpoint->channel_id);
1276	if (ret)
1277		goto out_suspend_again;
1278
1279	/* Finally, reset and reconfigure the channel again (re-enabling the
1280	 * the doorbell engine if appropriate).  Sleep for 1 millisecond to
1281	 * complete the channel reset sequence.  Finish by suspending the
1282	 * channel again (if necessary).
1283	 */
1284	legacy = ipa->version == IPA_VERSION_3_5_1;
1285	gsi_channel_reset(gsi, endpoint->channel_id, legacy);
1286
1287	msleep(1);
1288
1289	goto out_suspend_again;
1290
1291err_endpoint_stop:
1292	(void)gsi_channel_stop(gsi, endpoint->channel_id);
1293out_suspend_again:
1294	if (suspended)
1295		(void)ipa_endpoint_program_suspend(endpoint, true);
1296	dma_unmap_single(dev, addr, len, DMA_FROM_DEVICE);
1297out_kfree:
1298	kfree(virt);
1299
1300	return ret;
1301}
1302
1303static void ipa_endpoint_reset(struct ipa_endpoint *endpoint)
1304{
1305	u32 channel_id = endpoint->channel_id;
1306	struct ipa *ipa = endpoint->ipa;
1307	bool special;
1308	bool legacy;
1309	int ret = 0;
1310
1311	/* On IPA v3.5.1, if an RX endpoint is reset while aggregation
1312	 * is active, we need to handle things specially to recover.
1313	 * All other cases just need to reset the underlying GSI channel.
1314	 *
1315	 * IPA v3.5.1 enables the doorbell engine.  Newer versions do not.
1316	 */
1317	legacy = ipa->version == IPA_VERSION_3_5_1;
1318	special = !endpoint->toward_ipa && endpoint->data->aggregation;
1319	if (special && ipa_endpoint_aggr_active(endpoint))
1320		ret = ipa_endpoint_reset_rx_aggr(endpoint);
1321	else
1322		gsi_channel_reset(&ipa->gsi, channel_id, legacy);
1323
1324	if (ret)
1325		dev_err(&ipa->pdev->dev,
1326			"error %d resetting channel %u for endpoint %u\n",
1327			ret, endpoint->channel_id, endpoint->endpoint_id);
1328}
1329
1330static void ipa_endpoint_program(struct ipa_endpoint *endpoint)
1331{
1332	if (endpoint->toward_ipa)
1333		ipa_endpoint_program_delay(endpoint, false);
1334	else
1335		(void)ipa_endpoint_program_suspend(endpoint, false);
1336	ipa_endpoint_init_cfg(endpoint);
1337	ipa_endpoint_init_hdr(endpoint);
1338	ipa_endpoint_init_hdr_ext(endpoint);
1339	ipa_endpoint_init_hdr_metadata_mask(endpoint);
1340	ipa_endpoint_init_mode(endpoint);
1341	ipa_endpoint_init_aggr(endpoint);
1342	ipa_endpoint_init_deaggr(endpoint);
1343	ipa_endpoint_init_seq(endpoint);
1344	ipa_endpoint_status(endpoint);
1345}
1346
1347int ipa_endpoint_enable_one(struct ipa_endpoint *endpoint)
1348{
1349	struct ipa *ipa = endpoint->ipa;
1350	struct gsi *gsi = &ipa->gsi;
1351	int ret;
1352
1353	ret = gsi_channel_start(gsi, endpoint->channel_id);
1354	if (ret) {
1355		dev_err(&ipa->pdev->dev,
1356			"error %d starting %cX channel %u for endpoint %u\n",
1357			ret, endpoint->toward_ipa ? 'T' : 'R',
1358			endpoint->channel_id, endpoint->endpoint_id);
1359		return ret;
1360	}
1361
1362	if (!endpoint->toward_ipa) {
1363		ipa_interrupt_suspend_enable(ipa->interrupt,
1364					     endpoint->endpoint_id);
1365		ipa_endpoint_replenish_enable(endpoint);
1366	}
1367
1368	ipa->enabled |= BIT(endpoint->endpoint_id);
1369
1370	return 0;
1371}
1372
1373void ipa_endpoint_disable_one(struct ipa_endpoint *endpoint)
1374{
1375	u32 mask = BIT(endpoint->endpoint_id);
1376	struct ipa *ipa = endpoint->ipa;
1377	struct gsi *gsi = &ipa->gsi;
1378	int ret;
1379
1380	if (!(ipa->enabled & mask))
1381		return;
1382
1383	ipa->enabled ^= mask;
1384
1385	if (!endpoint->toward_ipa) {
1386		ipa_endpoint_replenish_disable(endpoint);
1387		ipa_interrupt_suspend_disable(ipa->interrupt,
1388					      endpoint->endpoint_id);
1389	}
1390
1391	/* Note that if stop fails, the channel's state is not well-defined */
1392	ret = gsi_channel_stop(gsi, endpoint->channel_id);
1393	if (ret)
1394		dev_err(&ipa->pdev->dev,
1395			"error %d attempting to stop endpoint %u\n", ret,
1396			endpoint->endpoint_id);
1397}
1398
1399void ipa_endpoint_suspend_one(struct ipa_endpoint *endpoint)
1400{
1401	struct device *dev = &endpoint->ipa->pdev->dev;
1402	struct gsi *gsi = &endpoint->ipa->gsi;
1403	bool stop_channel;
1404	int ret;
1405
1406	if (!(endpoint->ipa->enabled & BIT(endpoint->endpoint_id)))
1407		return;
1408
1409	if (!endpoint->toward_ipa) {
1410		ipa_endpoint_replenish_disable(endpoint);
1411		(void)ipa_endpoint_program_suspend(endpoint, true);
1412	}
1413
1414	/* IPA v3.5.1 doesn't use channel stop for suspend */
1415	stop_channel = endpoint->ipa->version != IPA_VERSION_3_5_1;
1416	ret = gsi_channel_suspend(gsi, endpoint->channel_id, stop_channel);
1417	if (ret)
1418		dev_err(dev, "error %d suspending channel %u\n", ret,
1419			endpoint->channel_id);
1420}
1421
1422void ipa_endpoint_resume_one(struct ipa_endpoint *endpoint)
1423{
1424	struct device *dev = &endpoint->ipa->pdev->dev;
1425	struct gsi *gsi = &endpoint->ipa->gsi;
1426	bool start_channel;
1427	int ret;
1428
1429	if (!(endpoint->ipa->enabled & BIT(endpoint->endpoint_id)))
1430		return;
1431
1432	if (!endpoint->toward_ipa)
1433		(void)ipa_endpoint_program_suspend(endpoint, false);
1434
1435	/* IPA v3.5.1 doesn't use channel start for resume */
1436	start_channel = endpoint->ipa->version != IPA_VERSION_3_5_1;
1437	ret = gsi_channel_resume(gsi, endpoint->channel_id, start_channel);
1438	if (ret)
1439		dev_err(dev, "error %d resuming channel %u\n", ret,
1440			endpoint->channel_id);
1441	else if (!endpoint->toward_ipa)
1442		ipa_endpoint_replenish_enable(endpoint);
1443}
1444
1445void ipa_endpoint_suspend(struct ipa *ipa)
1446{
1447	if (!ipa->setup_complete)
1448		return;
1449
1450	if (ipa->modem_netdev)
1451		ipa_modem_suspend(ipa->modem_netdev);
1452
1453	ipa_cmd_tag_process(ipa);
1454
1455	ipa_endpoint_suspend_one(ipa->name_map[IPA_ENDPOINT_AP_LAN_RX]);
1456	ipa_endpoint_suspend_one(ipa->name_map[IPA_ENDPOINT_AP_COMMAND_TX]);
1457}
1458
1459void ipa_endpoint_resume(struct ipa *ipa)
1460{
1461	if (!ipa->setup_complete)
1462		return;
1463
1464	ipa_endpoint_resume_one(ipa->name_map[IPA_ENDPOINT_AP_COMMAND_TX]);
1465	ipa_endpoint_resume_one(ipa->name_map[IPA_ENDPOINT_AP_LAN_RX]);
1466
1467	if (ipa->modem_netdev)
1468		ipa_modem_resume(ipa->modem_netdev);
1469}
1470
1471static void ipa_endpoint_setup_one(struct ipa_endpoint *endpoint)
1472{
1473	struct gsi *gsi = &endpoint->ipa->gsi;
1474	u32 channel_id = endpoint->channel_id;
1475
1476	/* Only AP endpoints get set up */
1477	if (endpoint->ee_id != GSI_EE_AP)
1478		return;
1479
1480	endpoint->trans_tre_max = gsi_channel_trans_tre_max(gsi, channel_id);
1481	if (!endpoint->toward_ipa) {
1482		/* RX transactions require a single TRE, so the maximum
1483		 * backlog is the same as the maximum outstanding TREs.
1484		 */
1485		clear_bit(IPA_REPLENISH_ENABLED, endpoint->replenish_flags);
1486		clear_bit(IPA_REPLENISH_ACTIVE, endpoint->replenish_flags);
1487		atomic_set(&endpoint->replenish_saved,
1488			   gsi_channel_tre_max(gsi, endpoint->channel_id));
1489		atomic_set(&endpoint->replenish_backlog, 0);
1490		INIT_DELAYED_WORK(&endpoint->replenish_work,
1491				  ipa_endpoint_replenish_work);
1492	}
1493
1494	ipa_endpoint_program(endpoint);
1495
1496	endpoint->ipa->set_up |= BIT(endpoint->endpoint_id);
1497}
1498
1499static void ipa_endpoint_teardown_one(struct ipa_endpoint *endpoint)
1500{
1501	endpoint->ipa->set_up &= ~BIT(endpoint->endpoint_id);
1502
1503	if (!endpoint->toward_ipa)
1504		cancel_delayed_work_sync(&endpoint->replenish_work);
1505
1506	ipa_endpoint_reset(endpoint);
1507}
1508
1509void ipa_endpoint_setup(struct ipa *ipa)
1510{
1511	u32 initialized = ipa->initialized;
1512
1513	ipa->set_up = 0;
1514	while (initialized) {
1515		u32 endpoint_id = __ffs(initialized);
1516
1517		initialized ^= BIT(endpoint_id);
1518
1519		ipa_endpoint_setup_one(&ipa->endpoint[endpoint_id]);
1520	}
1521}
1522
1523void ipa_endpoint_teardown(struct ipa *ipa)
1524{
1525	u32 set_up = ipa->set_up;
1526
1527	while (set_up) {
1528		u32 endpoint_id = __fls(set_up);
1529
1530		set_up ^= BIT(endpoint_id);
1531
1532		ipa_endpoint_teardown_one(&ipa->endpoint[endpoint_id]);
1533	}
1534	ipa->set_up = 0;
1535}
1536
1537int ipa_endpoint_config(struct ipa *ipa)
1538{
1539	struct device *dev = &ipa->pdev->dev;
1540	u32 initialized;
1541	u32 rx_base;
1542	u32 rx_mask;
1543	u32 tx_mask;
1544	int ret = 0;
1545	u32 max;
1546	u32 val;
1547
1548	/* Find out about the endpoints supplied by the hardware, and ensure
1549	 * the highest one doesn't exceed the number we support.
1550	 */
1551	val = ioread32(ipa->reg_virt + IPA_REG_FLAVOR_0_OFFSET);
1552
1553	/* Our RX is an IPA producer */
1554	rx_base = u32_get_bits(val, BAM_PROD_LOWEST_FMASK);
1555	max = rx_base + u32_get_bits(val, BAM_MAX_PROD_PIPES_FMASK);
1556	if (max > IPA_ENDPOINT_MAX) {
1557		dev_err(dev, "too many endpoints (%u > %u)\n",
1558			max, IPA_ENDPOINT_MAX);
1559		return -EINVAL;
1560	}
1561	rx_mask = GENMASK(max - 1, rx_base);
1562
1563	/* Our TX is an IPA consumer */
1564	max = u32_get_bits(val, BAM_MAX_CONS_PIPES_FMASK);
1565	tx_mask = GENMASK(max - 1, 0);
1566
1567	ipa->available = rx_mask | tx_mask;
1568
1569	/* Check for initialized endpoints not supported by the hardware */
1570	if (ipa->initialized & ~ipa->available) {
1571		dev_err(dev, "unavailable endpoint id(s) 0x%08x\n",
1572			ipa->initialized & ~ipa->available);
1573		ret = -EINVAL;		/* Report other errors too */
1574	}
1575
1576	initialized = ipa->initialized;
1577	while (initialized) {
1578		u32 endpoint_id = __ffs(initialized);
1579		struct ipa_endpoint *endpoint;
1580
1581		initialized ^= BIT(endpoint_id);
1582
1583		/* Make sure it's pointing in the right direction */
1584		endpoint = &ipa->endpoint[endpoint_id];
1585		if ((endpoint_id < rx_base) != !!endpoint->toward_ipa) {
1586			dev_err(dev, "endpoint id %u wrong direction\n",
1587				endpoint_id);
1588			ret = -EINVAL;
1589		}
1590	}
1591
1592	return ret;
1593}
1594
1595void ipa_endpoint_deconfig(struct ipa *ipa)
1596{
1597	ipa->available = 0;	/* Nothing more to do */
1598}
1599
1600static void ipa_endpoint_init_one(struct ipa *ipa, enum ipa_endpoint_name name,
1601				  const struct ipa_gsi_endpoint_data *data)
1602{
1603	struct ipa_endpoint *endpoint;
1604
1605	endpoint = &ipa->endpoint[data->endpoint_id];
1606
1607	if (data->ee_id == GSI_EE_AP)
1608		ipa->channel_map[data->channel_id] = endpoint;
1609	ipa->name_map[name] = endpoint;
1610
1611	endpoint->ipa = ipa;
1612	endpoint->ee_id = data->ee_id;
1613	endpoint->seq_type = data->endpoint.seq_type;
1614	endpoint->channel_id = data->channel_id;
1615	endpoint->endpoint_id = data->endpoint_id;
1616	endpoint->toward_ipa = data->toward_ipa;
1617	endpoint->data = &data->endpoint.config;
1618
1619	ipa->initialized |= BIT(endpoint->endpoint_id);
1620}
1621
1622void ipa_endpoint_exit_one(struct ipa_endpoint *endpoint)
1623{
1624	endpoint->ipa->initialized &= ~BIT(endpoint->endpoint_id);
1625
1626	memset(endpoint, 0, sizeof(*endpoint));
1627}
1628
1629void ipa_endpoint_exit(struct ipa *ipa)
1630{
1631	u32 initialized = ipa->initialized;
1632
1633	while (initialized) {
1634		u32 endpoint_id = __fls(initialized);
1635
1636		initialized ^= BIT(endpoint_id);
1637
1638		ipa_endpoint_exit_one(&ipa->endpoint[endpoint_id]);
1639	}
1640	memset(ipa->name_map, 0, sizeof(ipa->name_map));
1641	memset(ipa->channel_map, 0, sizeof(ipa->channel_map));
1642}
1643
1644/* Returns a bitmask of endpoints that support filtering, or 0 on error */
1645u32 ipa_endpoint_init(struct ipa *ipa, u32 count,
1646		      const struct ipa_gsi_endpoint_data *data)
1647{
1648	enum ipa_endpoint_name name;
1649	u32 filter_map;
1650
1651	if (!ipa_endpoint_data_valid(ipa, count, data))
1652		return 0;	/* Error */
1653
1654	ipa->initialized = 0;
1655
1656	filter_map = 0;
1657	for (name = 0; name < count; name++, data++) {
1658		if (ipa_gsi_endpoint_data_empty(data))
1659			continue;	/* Skip over empty slots */
1660
1661		ipa_endpoint_init_one(ipa, name, data);
1662
1663		if (data->endpoint.filter_support)
1664			filter_map |= BIT(data->endpoint_id);
1665	}
1666
1667	if (!ipa_filter_map_valid(ipa, filter_map))
1668		goto err_endpoint_exit;
1669
1670	return filter_map;	/* Non-zero bitmask */
1671
1672err_endpoint_exit:
1673	ipa_endpoint_exit(ipa);
1674
1675	return 0;	/* Error */
1676}
1677