xref: /linux/drivers/ufs/core/ufs-mcq.c (revision dbcedec3a31119d7594baacc743300d127c99c56)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2022 Qualcomm Innovation Center. All rights reserved.
4  *
5  * Authors:
6  *	Asutosh Das <quic_asutoshd@quicinc.com>
7  *	Can Guo <quic_cang@quicinc.com>
8  */
9 
10 #include <asm/unaligned.h>
11 #include <linux/dma-mapping.h>
12 #include <linux/module.h>
13 #include <linux/platform_device.h>
14 #include "ufshcd-priv.h"
15 #include <linux/delay.h>
16 #include <scsi/scsi_cmnd.h>
17 #include <linux/bitfield.h>
18 #include <linux/iopoll.h>
19 
20 #define MAX_QUEUE_SUP GENMASK(7, 0)
21 #define UFS_MCQ_MIN_RW_QUEUES 2
22 #define UFS_MCQ_MIN_READ_QUEUES 0
23 #define UFS_MCQ_MIN_POLL_QUEUES 0
24 #define QUEUE_EN_OFFSET 31
25 #define QUEUE_ID_OFFSET 16
26 
27 #define MCQ_CFG_MAC_MASK	GENMASK(16, 8)
28 #define MCQ_QCFG_SIZE		0x40
29 #define MCQ_ENTRY_SIZE_IN_DWORD	8
30 #define CQE_UCD_BA GENMASK_ULL(63, 7)
31 
32 /* Max mcq register polling time in microseconds */
33 #define MCQ_POLL_US 500000
34 
35 static int rw_queue_count_set(const char *val, const struct kernel_param *kp)
36 {
37 	return param_set_uint_minmax(val, kp, UFS_MCQ_MIN_RW_QUEUES,
38 				     num_possible_cpus());
39 }
40 
41 static const struct kernel_param_ops rw_queue_count_ops = {
42 	.set = rw_queue_count_set,
43 	.get = param_get_uint,
44 };
45 
46 static unsigned int rw_queues;
47 module_param_cb(rw_queues, &rw_queue_count_ops, &rw_queues, 0644);
48 MODULE_PARM_DESC(rw_queues,
49 		 "Number of interrupt driven I/O queues used for rw. Default value is nr_cpus");
50 
51 static int read_queue_count_set(const char *val, const struct kernel_param *kp)
52 {
53 	return param_set_uint_minmax(val, kp, UFS_MCQ_MIN_READ_QUEUES,
54 				     num_possible_cpus());
55 }
56 
57 static const struct kernel_param_ops read_queue_count_ops = {
58 	.set = read_queue_count_set,
59 	.get = param_get_uint,
60 };
61 
62 static unsigned int read_queues;
63 module_param_cb(read_queues, &read_queue_count_ops, &read_queues, 0644);
64 MODULE_PARM_DESC(read_queues,
65 		 "Number of interrupt driven read queues used for read. Default value is 0");
66 
67 static int poll_queue_count_set(const char *val, const struct kernel_param *kp)
68 {
69 	return param_set_uint_minmax(val, kp, UFS_MCQ_MIN_POLL_QUEUES,
70 				     num_possible_cpus());
71 }
72 
73 static const struct kernel_param_ops poll_queue_count_ops = {
74 	.set = poll_queue_count_set,
75 	.get = param_get_uint,
76 };
77 
78 static unsigned int poll_queues = 1;
79 module_param_cb(poll_queues, &poll_queue_count_ops, &poll_queues, 0644);
80 MODULE_PARM_DESC(poll_queues,
81 		 "Number of poll queues used for r/w. Default value is 1");
82 
83 /**
84  * ufshcd_mcq_config_mac - Set the #Max Activ Cmds.
85  * @hba: per adapter instance
86  * @max_active_cmds: maximum # of active commands to the device at any time.
87  *
88  * The controller won't send more than the max_active_cmds to the device at
89  * any time.
90  */
91 void ufshcd_mcq_config_mac(struct ufs_hba *hba, u32 max_active_cmds)
92 {
93 	u32 val;
94 
95 	val = ufshcd_readl(hba, REG_UFS_MCQ_CFG);
96 	val &= ~MCQ_CFG_MAC_MASK;
97 	val |= FIELD_PREP(MCQ_CFG_MAC_MASK, max_active_cmds - 1);
98 	ufshcd_writel(hba, val, REG_UFS_MCQ_CFG);
99 }
100 EXPORT_SYMBOL_GPL(ufshcd_mcq_config_mac);
101 
102 /**
103  * ufshcd_mcq_req_to_hwq - find the hardware queue on which the
104  * request would be issued.
105  * @hba: per adapter instance
106  * @req: pointer to the request to be issued
107  *
108  * Return: the hardware queue instance on which the request would
109  * be queued.
110  */
111 struct ufs_hw_queue *ufshcd_mcq_req_to_hwq(struct ufs_hba *hba,
112 					 struct request *req)
113 {
114 	u32 utag = blk_mq_unique_tag(req);
115 	u32 hwq = blk_mq_unique_tag_to_hwq(utag);
116 
117 	return &hba->uhq[hwq];
118 }
119 
120 /**
121  * ufshcd_mcq_decide_queue_depth - decide the queue depth
122  * @hba: per adapter instance
123  *
124  * Return: queue-depth on success, non-zero on error
125  *
126  * MAC - Max. Active Command of the Host Controller (HC)
127  * HC wouldn't send more than this commands to the device.
128  * It is mandatory to implement get_hba_mac() to enable MCQ mode.
129  * Calculates and adjusts the queue depth based on the depth
130  * supported by the HC and ufs device.
131  */
132 int ufshcd_mcq_decide_queue_depth(struct ufs_hba *hba)
133 {
134 	int mac;
135 
136 	/* Mandatory to implement get_hba_mac() */
137 	mac = ufshcd_mcq_vops_get_hba_mac(hba);
138 	if (mac < 0) {
139 		dev_err(hba->dev, "Failed to get mac, err=%d\n", mac);
140 		return mac;
141 	}
142 
143 	WARN_ON_ONCE(!hba->dev_info.bqueuedepth);
144 	/*
145 	 * max. value of bqueuedepth = 256, mac is host dependent.
146 	 * It is mandatory for UFS device to define bQueueDepth if
147 	 * shared queuing architecture is enabled.
148 	 */
149 	return min_t(int, mac, hba->dev_info.bqueuedepth);
150 }
151 
152 static int ufshcd_mcq_config_nr_queues(struct ufs_hba *hba)
153 {
154 	int i;
155 	u32 hba_maxq, rem, tot_queues;
156 	struct Scsi_Host *host = hba->host;
157 
158 	/* maxq is 0 based value */
159 	hba_maxq = FIELD_GET(MAX_QUEUE_SUP, hba->mcq_capabilities) + 1;
160 
161 	tot_queues = read_queues + poll_queues + rw_queues;
162 
163 	if (hba_maxq < tot_queues) {
164 		dev_err(hba->dev, "Total queues (%d) exceeds HC capacity (%d)\n",
165 			tot_queues, hba_maxq);
166 		return -EOPNOTSUPP;
167 	}
168 
169 	rem = hba_maxq;
170 
171 	if (rw_queues) {
172 		hba->nr_queues[HCTX_TYPE_DEFAULT] = rw_queues;
173 		rem -= hba->nr_queues[HCTX_TYPE_DEFAULT];
174 	} else {
175 		rw_queues = num_possible_cpus();
176 	}
177 
178 	if (poll_queues) {
179 		hba->nr_queues[HCTX_TYPE_POLL] = poll_queues;
180 		rem -= hba->nr_queues[HCTX_TYPE_POLL];
181 	}
182 
183 	if (read_queues) {
184 		hba->nr_queues[HCTX_TYPE_READ] = read_queues;
185 		rem -= hba->nr_queues[HCTX_TYPE_READ];
186 	}
187 
188 	if (!hba->nr_queues[HCTX_TYPE_DEFAULT])
189 		hba->nr_queues[HCTX_TYPE_DEFAULT] = min3(rem, rw_queues,
190 							 num_possible_cpus());
191 
192 	for (i = 0; i < HCTX_MAX_TYPES; i++)
193 		host->nr_hw_queues += hba->nr_queues[i];
194 
195 	hba->nr_hw_queues = host->nr_hw_queues;
196 	return 0;
197 }
198 
199 int ufshcd_mcq_memory_alloc(struct ufs_hba *hba)
200 {
201 	struct ufs_hw_queue *hwq;
202 	size_t utrdl_size, cqe_size;
203 	int i;
204 
205 	for (i = 0; i < hba->nr_hw_queues; i++) {
206 		hwq = &hba->uhq[i];
207 
208 		utrdl_size = sizeof(struct utp_transfer_req_desc) *
209 			     hwq->max_entries;
210 		hwq->sqe_base_addr = dmam_alloc_coherent(hba->dev, utrdl_size,
211 							 &hwq->sqe_dma_addr,
212 							 GFP_KERNEL);
213 		if (!hwq->sqe_dma_addr) {
214 			dev_err(hba->dev, "SQE allocation failed\n");
215 			return -ENOMEM;
216 		}
217 
218 		cqe_size = sizeof(struct cq_entry) * hwq->max_entries;
219 		hwq->cqe_base_addr = dmam_alloc_coherent(hba->dev, cqe_size,
220 							 &hwq->cqe_dma_addr,
221 							 GFP_KERNEL);
222 		if (!hwq->cqe_dma_addr) {
223 			dev_err(hba->dev, "CQE allocation failed\n");
224 			return -ENOMEM;
225 		}
226 	}
227 
228 	return 0;
229 }
230 
231 
232 /* Operation and runtime registers configuration */
233 #define MCQ_CFG_n(r, i)	((r) + MCQ_QCFG_SIZE * (i))
234 #define MCQ_OPR_OFFSET_n(p, i) \
235 	(hba->mcq_opr[(p)].offset + hba->mcq_opr[(p)].stride * (i))
236 
237 static void __iomem *mcq_opr_base(struct ufs_hba *hba,
238 					 enum ufshcd_mcq_opr n, int i)
239 {
240 	struct ufshcd_mcq_opr_info_t *opr = &hba->mcq_opr[n];
241 
242 	return opr->base + opr->stride * i;
243 }
244 
245 u32 ufshcd_mcq_read_cqis(struct ufs_hba *hba, int i)
246 {
247 	return readl(mcq_opr_base(hba, OPR_CQIS, i) + REG_CQIS);
248 }
249 EXPORT_SYMBOL_GPL(ufshcd_mcq_read_cqis);
250 
251 void ufshcd_mcq_write_cqis(struct ufs_hba *hba, u32 val, int i)
252 {
253 	writel(val, mcq_opr_base(hba, OPR_CQIS, i) + REG_CQIS);
254 }
255 EXPORT_SYMBOL_GPL(ufshcd_mcq_write_cqis);
256 
257 /*
258  * Current MCQ specification doesn't provide a Task Tag or its equivalent in
259  * the Completion Queue Entry. Find the Task Tag using an indirect method.
260  */
261 static int ufshcd_mcq_get_tag(struct ufs_hba *hba, struct cq_entry *cqe)
262 {
263 	u64 addr;
264 
265 	/* sizeof(struct utp_transfer_cmd_desc) must be a multiple of 128 */
266 	BUILD_BUG_ON(sizeof(struct utp_transfer_cmd_desc) & GENMASK(6, 0));
267 
268 	/* Bits 63:7 UCD base address, 6:5 are reserved, 4:0 is SQ ID */
269 	addr = (le64_to_cpu(cqe->command_desc_base_addr) & CQE_UCD_BA) -
270 		hba->ucdl_dma_addr;
271 
272 	return div_u64(addr, ufshcd_get_ucd_size(hba));
273 }
274 
275 static void ufshcd_mcq_process_cqe(struct ufs_hba *hba,
276 				   struct ufs_hw_queue *hwq)
277 {
278 	struct cq_entry *cqe = ufshcd_mcq_cur_cqe(hwq);
279 	int tag = ufshcd_mcq_get_tag(hba, cqe);
280 
281 	if (cqe->command_desc_base_addr) {
282 		ufshcd_compl_one_cqe(hba, tag, cqe);
283 		/* After processed the cqe, mark it empty (invalid) entry */
284 		cqe->command_desc_base_addr = 0;
285 	}
286 }
287 
288 void ufshcd_mcq_compl_all_cqes_lock(struct ufs_hba *hba,
289 				    struct ufs_hw_queue *hwq)
290 {
291 	unsigned long flags;
292 	u32 entries = hwq->max_entries;
293 
294 	spin_lock_irqsave(&hwq->cq_lock, flags);
295 	while (entries > 0) {
296 		ufshcd_mcq_process_cqe(hba, hwq);
297 		ufshcd_mcq_inc_cq_head_slot(hwq);
298 		entries--;
299 	}
300 
301 	ufshcd_mcq_update_cq_tail_slot(hwq);
302 	hwq->cq_head_slot = hwq->cq_tail_slot;
303 	spin_unlock_irqrestore(&hwq->cq_lock, flags);
304 }
305 
306 unsigned long ufshcd_mcq_poll_cqe_lock(struct ufs_hba *hba,
307 				       struct ufs_hw_queue *hwq)
308 {
309 	unsigned long completed_reqs = 0;
310 	unsigned long flags;
311 
312 	spin_lock_irqsave(&hwq->cq_lock, flags);
313 	ufshcd_mcq_update_cq_tail_slot(hwq);
314 	while (!ufshcd_mcq_is_cq_empty(hwq)) {
315 		ufshcd_mcq_process_cqe(hba, hwq);
316 		ufshcd_mcq_inc_cq_head_slot(hwq);
317 		completed_reqs++;
318 	}
319 
320 	if (completed_reqs)
321 		ufshcd_mcq_update_cq_head(hwq);
322 	spin_unlock_irqrestore(&hwq->cq_lock, flags);
323 
324 	return completed_reqs;
325 }
326 EXPORT_SYMBOL_GPL(ufshcd_mcq_poll_cqe_lock);
327 
328 void ufshcd_mcq_make_queues_operational(struct ufs_hba *hba)
329 {
330 	struct ufs_hw_queue *hwq;
331 	u16 qsize;
332 	int i;
333 
334 	for (i = 0; i < hba->nr_hw_queues; i++) {
335 		hwq = &hba->uhq[i];
336 		hwq->id = i;
337 		qsize = hwq->max_entries * MCQ_ENTRY_SIZE_IN_DWORD - 1;
338 
339 		/* Submission Queue Lower Base Address */
340 		ufsmcq_writelx(hba, lower_32_bits(hwq->sqe_dma_addr),
341 			      MCQ_CFG_n(REG_SQLBA, i));
342 		/* Submission Queue Upper Base Address */
343 		ufsmcq_writelx(hba, upper_32_bits(hwq->sqe_dma_addr),
344 			      MCQ_CFG_n(REG_SQUBA, i));
345 		/* Submission Queue Doorbell Address Offset */
346 		ufsmcq_writelx(hba, MCQ_OPR_OFFSET_n(OPR_SQD, i),
347 			      MCQ_CFG_n(REG_SQDAO, i));
348 		/* Submission Queue Interrupt Status Address Offset */
349 		ufsmcq_writelx(hba, MCQ_OPR_OFFSET_n(OPR_SQIS, i),
350 			      MCQ_CFG_n(REG_SQISAO, i));
351 
352 		/* Completion Queue Lower Base Address */
353 		ufsmcq_writelx(hba, lower_32_bits(hwq->cqe_dma_addr),
354 			      MCQ_CFG_n(REG_CQLBA, i));
355 		/* Completion Queue Upper Base Address */
356 		ufsmcq_writelx(hba, upper_32_bits(hwq->cqe_dma_addr),
357 			      MCQ_CFG_n(REG_CQUBA, i));
358 		/* Completion Queue Doorbell Address Offset */
359 		ufsmcq_writelx(hba, MCQ_OPR_OFFSET_n(OPR_CQD, i),
360 			      MCQ_CFG_n(REG_CQDAO, i));
361 		/* Completion Queue Interrupt Status Address Offset */
362 		ufsmcq_writelx(hba, MCQ_OPR_OFFSET_n(OPR_CQIS, i),
363 			      MCQ_CFG_n(REG_CQISAO, i));
364 
365 		/* Save the base addresses for quicker access */
366 		hwq->mcq_sq_head = mcq_opr_base(hba, OPR_SQD, i) + REG_SQHP;
367 		hwq->mcq_sq_tail = mcq_opr_base(hba, OPR_SQD, i) + REG_SQTP;
368 		hwq->mcq_cq_head = mcq_opr_base(hba, OPR_CQD, i) + REG_CQHP;
369 		hwq->mcq_cq_tail = mcq_opr_base(hba, OPR_CQD, i) + REG_CQTP;
370 
371 		/* Reinitializing is needed upon HC reset */
372 		hwq->sq_tail_slot = hwq->cq_tail_slot = hwq->cq_head_slot = 0;
373 
374 		/* Enable Tail Entry Push Status interrupt only for non-poll queues */
375 		if (i < hba->nr_hw_queues - hba->nr_queues[HCTX_TYPE_POLL])
376 			writel(1, mcq_opr_base(hba, OPR_CQIS, i) + REG_CQIE);
377 
378 		/* Completion Queue Enable|Size to Completion Queue Attribute */
379 		ufsmcq_writel(hba, (1 << QUEUE_EN_OFFSET) | qsize,
380 			      MCQ_CFG_n(REG_CQATTR, i));
381 
382 		/*
383 		 * Submission Qeueue Enable|Size|Completion Queue ID to
384 		 * Submission Queue Attribute
385 		 */
386 		ufsmcq_writel(hba, (1 << QUEUE_EN_OFFSET) | qsize |
387 			      (i << QUEUE_ID_OFFSET),
388 			      MCQ_CFG_n(REG_SQATTR, i));
389 	}
390 }
391 EXPORT_SYMBOL_GPL(ufshcd_mcq_make_queues_operational);
392 
393 void ufshcd_mcq_enable_esi(struct ufs_hba *hba)
394 {
395 	ufshcd_writel(hba, ufshcd_readl(hba, REG_UFS_MEM_CFG) | 0x2,
396 		      REG_UFS_MEM_CFG);
397 }
398 EXPORT_SYMBOL_GPL(ufshcd_mcq_enable_esi);
399 
400 void ufshcd_mcq_enable(struct ufs_hba *hba)
401 {
402 	ufshcd_rmwl(hba, MCQ_MODE_SELECT, MCQ_MODE_SELECT, REG_UFS_MEM_CFG);
403 }
404 EXPORT_SYMBOL_GPL(ufshcd_mcq_enable);
405 
406 void ufshcd_mcq_config_esi(struct ufs_hba *hba, struct msi_msg *msg)
407 {
408 	ufshcd_writel(hba, msg->address_lo, REG_UFS_ESILBA);
409 	ufshcd_writel(hba, msg->address_hi, REG_UFS_ESIUBA);
410 }
411 EXPORT_SYMBOL_GPL(ufshcd_mcq_config_esi);
412 
413 int ufshcd_mcq_init(struct ufs_hba *hba)
414 {
415 	struct Scsi_Host *host = hba->host;
416 	struct ufs_hw_queue *hwq;
417 	int ret, i;
418 
419 	ret = ufshcd_mcq_config_nr_queues(hba);
420 	if (ret)
421 		return ret;
422 
423 	ret = ufshcd_vops_mcq_config_resource(hba);
424 	if (ret)
425 		return ret;
426 
427 	ret = ufshcd_mcq_vops_op_runtime_config(hba);
428 	if (ret) {
429 		dev_err(hba->dev, "Operation runtime config failed, ret=%d\n",
430 			ret);
431 		return ret;
432 	}
433 	hba->uhq = devm_kzalloc(hba->dev,
434 				hba->nr_hw_queues * sizeof(struct ufs_hw_queue),
435 				GFP_KERNEL);
436 	if (!hba->uhq) {
437 		dev_err(hba->dev, "ufs hw queue memory allocation failed\n");
438 		return -ENOMEM;
439 	}
440 
441 	for (i = 0; i < hba->nr_hw_queues; i++) {
442 		hwq = &hba->uhq[i];
443 		hwq->max_entries = hba->nutrs + 1;
444 		spin_lock_init(&hwq->sq_lock);
445 		spin_lock_init(&hwq->cq_lock);
446 		mutex_init(&hwq->sq_mutex);
447 	}
448 
449 	/* The very first HW queue serves device commands */
450 	hba->dev_cmd_queue = &hba->uhq[0];
451 
452 	host->host_tagset = 1;
453 	return 0;
454 }
455 
456 static int ufshcd_mcq_sq_stop(struct ufs_hba *hba, struct ufs_hw_queue *hwq)
457 {
458 	void __iomem *reg;
459 	u32 id = hwq->id, val;
460 	int err;
461 
462 	if (hba->quirks & UFSHCD_QUIRK_MCQ_BROKEN_RTC)
463 		return -ETIMEDOUT;
464 
465 	writel(SQ_STOP, mcq_opr_base(hba, OPR_SQD, id) + REG_SQRTC);
466 	reg = mcq_opr_base(hba, OPR_SQD, id) + REG_SQRTS;
467 	err = read_poll_timeout(readl, val, val & SQ_STS, 20,
468 				MCQ_POLL_US, false, reg);
469 	if (err)
470 		dev_err(hba->dev, "%s: failed. hwq-id=%d, err=%d\n",
471 			__func__, id, err);
472 	return err;
473 }
474 
475 static int ufshcd_mcq_sq_start(struct ufs_hba *hba, struct ufs_hw_queue *hwq)
476 {
477 	void __iomem *reg;
478 	u32 id = hwq->id, val;
479 	int err;
480 
481 	if (hba->quirks & UFSHCD_QUIRK_MCQ_BROKEN_RTC)
482 		return -ETIMEDOUT;
483 
484 	writel(SQ_START, mcq_opr_base(hba, OPR_SQD, id) + REG_SQRTC);
485 	reg = mcq_opr_base(hba, OPR_SQD, id) + REG_SQRTS;
486 	err = read_poll_timeout(readl, val, !(val & SQ_STS), 20,
487 				MCQ_POLL_US, false, reg);
488 	if (err)
489 		dev_err(hba->dev, "%s: failed. hwq-id=%d, err=%d\n",
490 			__func__, id, err);
491 	return err;
492 }
493 
494 /**
495  * ufshcd_mcq_sq_cleanup - Clean up submission queue resources
496  * associated with the pending command.
497  * @hba: per adapter instance.
498  * @task_tag: The command's task tag.
499  *
500  * Return: 0 for success; error code otherwise.
501  */
502 int ufshcd_mcq_sq_cleanup(struct ufs_hba *hba, int task_tag)
503 {
504 	struct ufshcd_lrb *lrbp = &hba->lrb[task_tag];
505 	struct scsi_cmnd *cmd = lrbp->cmd;
506 	struct ufs_hw_queue *hwq;
507 	void __iomem *reg, *opr_sqd_base;
508 	u32 nexus, id, val;
509 	int err;
510 
511 	if (hba->quirks & UFSHCD_QUIRK_MCQ_BROKEN_RTC)
512 		return -ETIMEDOUT;
513 
514 	if (task_tag != hba->nutrs - UFSHCD_NUM_RESERVED) {
515 		if (!cmd)
516 			return -EINVAL;
517 		hwq = ufshcd_mcq_req_to_hwq(hba, scsi_cmd_to_rq(cmd));
518 	} else {
519 		hwq = hba->dev_cmd_queue;
520 	}
521 
522 	id = hwq->id;
523 
524 	mutex_lock(&hwq->sq_mutex);
525 
526 	/* stop the SQ fetching before working on it */
527 	err = ufshcd_mcq_sq_stop(hba, hwq);
528 	if (err)
529 		goto unlock;
530 
531 	/* SQCTI = EXT_IID, IID, LUN, Task Tag */
532 	nexus = lrbp->lun << 8 | task_tag;
533 	opr_sqd_base = mcq_opr_base(hba, OPR_SQD, id);
534 	writel(nexus, opr_sqd_base + REG_SQCTI);
535 
536 	/* SQRTCy.ICU = 1 */
537 	writel(SQ_ICU, opr_sqd_base + REG_SQRTC);
538 
539 	/* Poll SQRTSy.CUS = 1. Return result from SQRTSy.RTC */
540 	reg = opr_sqd_base + REG_SQRTS;
541 	err = read_poll_timeout(readl, val, val & SQ_CUS, 20,
542 				MCQ_POLL_US, false, reg);
543 	if (err)
544 		dev_err(hba->dev, "%s: failed. hwq=%d, tag=%d err=%ld\n",
545 			__func__, id, task_tag,
546 			FIELD_GET(SQ_ICU_ERR_CODE_MASK, readl(reg)));
547 
548 	if (ufshcd_mcq_sq_start(hba, hwq))
549 		err = -ETIMEDOUT;
550 
551 unlock:
552 	mutex_unlock(&hwq->sq_mutex);
553 	return err;
554 }
555 
556 /**
557  * ufshcd_mcq_nullify_sqe - Nullify the submission queue entry.
558  * Write the sqe's Command Type to 0xF. The host controller will not
559  * fetch any sqe with Command Type = 0xF.
560  *
561  * @utrd: UTP Transfer Request Descriptor to be nullified.
562  */
563 static void ufshcd_mcq_nullify_sqe(struct utp_transfer_req_desc *utrd)
564 {
565 	utrd->header.command_type = 0xf;
566 }
567 
568 /**
569  * ufshcd_mcq_sqe_search - Search for the command in the submission queue
570  * If the command is in the submission queue and not issued to the device yet,
571  * nullify the sqe so the host controller will skip fetching the sqe.
572  *
573  * @hba: per adapter instance.
574  * @hwq: Hardware Queue to be searched.
575  * @task_tag: The command's task tag.
576  *
577  * Return: true if the SQE containing the command is present in the SQ
578  * (not fetched by the controller); returns false if the SQE is not in the SQ.
579  */
580 static bool ufshcd_mcq_sqe_search(struct ufs_hba *hba,
581 				  struct ufs_hw_queue *hwq, int task_tag)
582 {
583 	struct ufshcd_lrb *lrbp = &hba->lrb[task_tag];
584 	struct utp_transfer_req_desc *utrd;
585 	__le64  cmd_desc_base_addr;
586 	bool ret = false;
587 	u64 addr, match;
588 	u32 sq_head_slot;
589 
590 	if (hba->quirks & UFSHCD_QUIRK_MCQ_BROKEN_RTC)
591 		return true;
592 
593 	mutex_lock(&hwq->sq_mutex);
594 
595 	ufshcd_mcq_sq_stop(hba, hwq);
596 	sq_head_slot = ufshcd_mcq_get_sq_head_slot(hwq);
597 	if (sq_head_slot == hwq->sq_tail_slot)
598 		goto out;
599 
600 	cmd_desc_base_addr = lrbp->utr_descriptor_ptr->command_desc_base_addr;
601 	addr = le64_to_cpu(cmd_desc_base_addr) & CQE_UCD_BA;
602 
603 	while (sq_head_slot != hwq->sq_tail_slot) {
604 		utrd = hwq->sqe_base_addr +
605 				sq_head_slot * sizeof(struct utp_transfer_req_desc);
606 		match = le64_to_cpu(utrd->command_desc_base_addr) & CQE_UCD_BA;
607 		if (addr == match) {
608 			ufshcd_mcq_nullify_sqe(utrd);
609 			ret = true;
610 			goto out;
611 		}
612 
613 		sq_head_slot++;
614 		if (sq_head_slot == hwq->max_entries)
615 			sq_head_slot = 0;
616 	}
617 
618 out:
619 	ufshcd_mcq_sq_start(hba, hwq);
620 	mutex_unlock(&hwq->sq_mutex);
621 	return ret;
622 }
623 
624 /**
625  * ufshcd_mcq_abort - Abort the command in MCQ.
626  * @cmd: The command to be aborted.
627  *
628  * Return: SUCCESS or FAILED error codes
629  */
630 int ufshcd_mcq_abort(struct scsi_cmnd *cmd)
631 {
632 	struct Scsi_Host *host = cmd->device->host;
633 	struct ufs_hba *hba = shost_priv(host);
634 	int tag = scsi_cmd_to_rq(cmd)->tag;
635 	struct ufshcd_lrb *lrbp = &hba->lrb[tag];
636 	struct ufs_hw_queue *hwq;
637 	unsigned long flags;
638 	int err = FAILED;
639 
640 	if (!ufshcd_cmd_inflight(lrbp->cmd)) {
641 		dev_err(hba->dev,
642 			"%s: skip abort. cmd at tag %d already completed.\n",
643 			__func__, tag);
644 		goto out;
645 	}
646 
647 	/* Skip task abort in case previous aborts failed and report failure */
648 	if (lrbp->req_abort_skip) {
649 		dev_err(hba->dev, "%s: skip abort. tag %d failed earlier\n",
650 			__func__, tag);
651 		goto out;
652 	}
653 
654 	hwq = ufshcd_mcq_req_to_hwq(hba, scsi_cmd_to_rq(cmd));
655 
656 	if (ufshcd_mcq_sqe_search(hba, hwq, tag)) {
657 		/*
658 		 * Failure. The command should not be "stuck" in SQ for
659 		 * a long time which resulted in command being aborted.
660 		 */
661 		dev_err(hba->dev, "%s: cmd found in sq. hwq=%d, tag=%d\n",
662 			__func__, hwq->id, tag);
663 		goto out;
664 	}
665 
666 	/*
667 	 * The command is not in the submission queue, and it is not
668 	 * in the completion queue either. Query the device to see if
669 	 * the command is being processed in the device.
670 	 */
671 	if (ufshcd_try_to_abort_task(hba, tag)) {
672 		dev_err(hba->dev, "%s: device abort failed %d\n", __func__, err);
673 		lrbp->req_abort_skip = true;
674 		goto out;
675 	}
676 
677 	err = SUCCESS;
678 	spin_lock_irqsave(&hwq->cq_lock, flags);
679 	if (ufshcd_cmd_inflight(lrbp->cmd))
680 		ufshcd_release_scsi_cmd(hba, lrbp);
681 	spin_unlock_irqrestore(&hwq->cq_lock, flags);
682 
683 out:
684 	return err;
685 }
686