xref: /openbmc/u-boot/drivers/nvme/nvme.c (revision fabbeb33)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2017 NXP Semiconductors
4  * Copyright (C) 2017 Bin Meng <bmeng.cn@gmail.com>
5  */
6 
7 #include <common.h>
8 #include <dm.h>
9 #include <errno.h>
10 #include <memalign.h>
11 #include <pci.h>
12 #include <dm/device-internal.h>
13 #include "nvme.h"
14 
15 #define NVME_Q_DEPTH		2
16 #define NVME_AQ_DEPTH		2
17 #define NVME_SQ_SIZE(depth)	(depth * sizeof(struct nvme_command))
18 #define NVME_CQ_SIZE(depth)	(depth * sizeof(struct nvme_completion))
19 #define ADMIN_TIMEOUT		60
20 #define IO_TIMEOUT		30
21 #define MAX_PRP_POOL		512
22 
23 enum nvme_queue_id {
24 	NVME_ADMIN_Q,
25 	NVME_IO_Q,
26 	NVME_Q_NUM,
27 };
28 
29 /*
30  * An NVM Express queue. Each device has at least two (one for admin
31  * commands and one for I/O commands).
32  */
33 struct nvme_queue {
34 	struct nvme_dev *dev;
35 	struct nvme_command *sq_cmds;
36 	struct nvme_completion *cqes;
37 	wait_queue_head_t sq_full;
38 	u32 __iomem *q_db;
39 	u16 q_depth;
40 	s16 cq_vector;
41 	u16 sq_head;
42 	u16 sq_tail;
43 	u16 cq_head;
44 	u16 qid;
45 	u8 cq_phase;
46 	u8 cqe_seen;
47 	unsigned long cmdid_data[];
48 };
49 
50 static int nvme_wait_ready(struct nvme_dev *dev, bool enabled)
51 {
52 	u32 bit = enabled ? NVME_CSTS_RDY : 0;
53 	int timeout;
54 	ulong start;
55 
56 	/* Timeout field in the CAP register is in 500 millisecond units */
57 	timeout = NVME_CAP_TIMEOUT(dev->cap) * 500;
58 
59 	start = get_timer(0);
60 	while (get_timer(start) < timeout) {
61 		if ((readl(&dev->bar->csts) & NVME_CSTS_RDY) == bit)
62 			return 0;
63 	}
64 
65 	return -ETIME;
66 }
67 
68 static int nvme_setup_prps(struct nvme_dev *dev, u64 *prp2,
69 			   int total_len, u64 dma_addr)
70 {
71 	u32 page_size = dev->page_size;
72 	int offset = dma_addr & (page_size - 1);
73 	u64 *prp_pool;
74 	int length = total_len;
75 	int i, nprps;
76 	length -= (page_size - offset);
77 
78 	if (length <= 0) {
79 		*prp2 = 0;
80 		return 0;
81 	}
82 
83 	if (length)
84 		dma_addr += (page_size - offset);
85 
86 	if (length <= page_size) {
87 		*prp2 = dma_addr;
88 		return 0;
89 	}
90 
91 	nprps = DIV_ROUND_UP(length, page_size);
92 
93 	if (nprps > dev->prp_entry_num) {
94 		free(dev->prp_pool);
95 		dev->prp_pool = malloc(nprps << 3);
96 		if (!dev->prp_pool) {
97 			printf("Error: malloc prp_pool fail\n");
98 			return -ENOMEM;
99 		}
100 		dev->prp_entry_num = nprps;
101 	}
102 
103 	prp_pool = dev->prp_pool;
104 	i = 0;
105 	while (nprps) {
106 		if (i == ((page_size >> 3) - 1)) {
107 			*(prp_pool + i) = cpu_to_le64((ulong)prp_pool +
108 					page_size);
109 			i = 0;
110 			prp_pool += page_size;
111 		}
112 		*(prp_pool + i++) = cpu_to_le64(dma_addr);
113 		dma_addr += page_size;
114 		nprps--;
115 	}
116 	*prp2 = (ulong)dev->prp_pool;
117 
118 	return 0;
119 }
120 
121 static __le16 nvme_get_cmd_id(void)
122 {
123 	static unsigned short cmdid;
124 
125 	return cpu_to_le16((cmdid < USHRT_MAX) ? cmdid++ : 0);
126 }
127 
128 static u16 nvme_read_completion_status(struct nvme_queue *nvmeq, u16 index)
129 {
130 	u64 start = (ulong)&nvmeq->cqes[index];
131 	u64 stop = start + sizeof(struct nvme_completion);
132 
133 	invalidate_dcache_range(start, stop);
134 
135 	return le16_to_cpu(readw(&(nvmeq->cqes[index].status)));
136 }
137 
138 /**
139  * nvme_submit_cmd() - copy a command into a queue and ring the doorbell
140  *
141  * @nvmeq:	The queue to use
142  * @cmd:	The command to send
143  */
144 static void nvme_submit_cmd(struct nvme_queue *nvmeq, struct nvme_command *cmd)
145 {
146 	u16 tail = nvmeq->sq_tail;
147 
148 	memcpy(&nvmeq->sq_cmds[tail], cmd, sizeof(*cmd));
149 	flush_dcache_range((ulong)&nvmeq->sq_cmds[tail],
150 			   (ulong)&nvmeq->sq_cmds[tail] + sizeof(*cmd));
151 
152 	if (++tail == nvmeq->q_depth)
153 		tail = 0;
154 	writel(tail, nvmeq->q_db);
155 	nvmeq->sq_tail = tail;
156 }
157 
158 static int nvme_submit_sync_cmd(struct nvme_queue *nvmeq,
159 				struct nvme_command *cmd,
160 				u32 *result, unsigned timeout)
161 {
162 	u16 head = nvmeq->cq_head;
163 	u16 phase = nvmeq->cq_phase;
164 	u16 status;
165 	ulong start_time;
166 	ulong timeout_us = timeout * 100000;
167 
168 	cmd->common.command_id = nvme_get_cmd_id();
169 	nvme_submit_cmd(nvmeq, cmd);
170 
171 	start_time = timer_get_us();
172 
173 	for (;;) {
174 		status = nvme_read_completion_status(nvmeq, head);
175 		if ((status & 0x01) == phase)
176 			break;
177 		if (timeout_us > 0 && (timer_get_us() - start_time)
178 		    >= timeout_us)
179 			return -ETIMEDOUT;
180 	}
181 
182 	status >>= 1;
183 	if (status) {
184 		printf("ERROR: status = %x, phase = %d, head = %d\n",
185 		       status, phase, head);
186 		status = 0;
187 		if (++head == nvmeq->q_depth) {
188 			head = 0;
189 			phase = !phase;
190 		}
191 		writel(head, nvmeq->q_db + nvmeq->dev->db_stride);
192 		nvmeq->cq_head = head;
193 		nvmeq->cq_phase = phase;
194 
195 		return -EIO;
196 	}
197 
198 	if (result)
199 		*result = le32_to_cpu(readl(&(nvmeq->cqes[head].result)));
200 
201 	if (++head == nvmeq->q_depth) {
202 		head = 0;
203 		phase = !phase;
204 	}
205 	writel(head, nvmeq->q_db + nvmeq->dev->db_stride);
206 	nvmeq->cq_head = head;
207 	nvmeq->cq_phase = phase;
208 
209 	return status;
210 }
211 
212 static int nvme_submit_admin_cmd(struct nvme_dev *dev, struct nvme_command *cmd,
213 				 u32 *result)
214 {
215 	return nvme_submit_sync_cmd(dev->queues[NVME_ADMIN_Q], cmd,
216 				    result, ADMIN_TIMEOUT);
217 }
218 
219 static struct nvme_queue *nvme_alloc_queue(struct nvme_dev *dev,
220 					   int qid, int depth)
221 {
222 	struct nvme_queue *nvmeq = malloc(sizeof(*nvmeq));
223 	if (!nvmeq)
224 		return NULL;
225 	memset(nvmeq, 0, sizeof(*nvmeq));
226 
227 	nvmeq->cqes = (void *)memalign(4096, NVME_CQ_SIZE(depth));
228 	if (!nvmeq->cqes)
229 		goto free_nvmeq;
230 	memset((void *)nvmeq->cqes, 0, NVME_CQ_SIZE(depth));
231 
232 	nvmeq->sq_cmds = (void *)memalign(4096, NVME_SQ_SIZE(depth));
233 	if (!nvmeq->sq_cmds)
234 		goto free_queue;
235 	memset((void *)nvmeq->sq_cmds, 0, NVME_SQ_SIZE(depth));
236 
237 	nvmeq->dev = dev;
238 
239 	nvmeq->cq_head = 0;
240 	nvmeq->cq_phase = 1;
241 	nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
242 	nvmeq->q_depth = depth;
243 	nvmeq->qid = qid;
244 	dev->queue_count++;
245 	dev->queues[qid] = nvmeq;
246 
247 	return nvmeq;
248 
249  free_queue:
250 	free((void *)nvmeq->cqes);
251  free_nvmeq:
252 	free(nvmeq);
253 
254 	return NULL;
255 }
256 
257 static int nvme_delete_queue(struct nvme_dev *dev, u8 opcode, u16 id)
258 {
259 	struct nvme_command c;
260 
261 	memset(&c, 0, sizeof(c));
262 	c.delete_queue.opcode = opcode;
263 	c.delete_queue.qid = cpu_to_le16(id);
264 
265 	return nvme_submit_admin_cmd(dev, &c, NULL);
266 }
267 
268 static int nvme_delete_sq(struct nvme_dev *dev, u16 sqid)
269 {
270 	return nvme_delete_queue(dev, nvme_admin_delete_sq, sqid);
271 }
272 
273 static int nvme_delete_cq(struct nvme_dev *dev, u16 cqid)
274 {
275 	return nvme_delete_queue(dev, nvme_admin_delete_cq, cqid);
276 }
277 
278 static int nvme_enable_ctrl(struct nvme_dev *dev)
279 {
280 	dev->ctrl_config &= ~NVME_CC_SHN_MASK;
281 	dev->ctrl_config |= NVME_CC_ENABLE;
282 	writel(cpu_to_le32(dev->ctrl_config), &dev->bar->cc);
283 
284 	return nvme_wait_ready(dev, true);
285 }
286 
287 static int nvme_disable_ctrl(struct nvme_dev *dev)
288 {
289 	dev->ctrl_config &= ~NVME_CC_SHN_MASK;
290 	dev->ctrl_config &= ~NVME_CC_ENABLE;
291 	writel(cpu_to_le32(dev->ctrl_config), &dev->bar->cc);
292 
293 	return nvme_wait_ready(dev, false);
294 }
295 
296 static void nvme_free_queue(struct nvme_queue *nvmeq)
297 {
298 	free((void *)nvmeq->cqes);
299 	free(nvmeq->sq_cmds);
300 	free(nvmeq);
301 }
302 
303 static void nvme_free_queues(struct nvme_dev *dev, int lowest)
304 {
305 	int i;
306 
307 	for (i = dev->queue_count - 1; i >= lowest; i--) {
308 		struct nvme_queue *nvmeq = dev->queues[i];
309 		dev->queue_count--;
310 		dev->queues[i] = NULL;
311 		nvme_free_queue(nvmeq);
312 	}
313 }
314 
315 static void nvme_init_queue(struct nvme_queue *nvmeq, u16 qid)
316 {
317 	struct nvme_dev *dev = nvmeq->dev;
318 
319 	nvmeq->sq_tail = 0;
320 	nvmeq->cq_head = 0;
321 	nvmeq->cq_phase = 1;
322 	nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
323 	memset((void *)nvmeq->cqes, 0, NVME_CQ_SIZE(nvmeq->q_depth));
324 	flush_dcache_range((ulong)nvmeq->cqes,
325 			   (ulong)nvmeq->cqes + NVME_CQ_SIZE(nvmeq->q_depth));
326 	dev->online_queues++;
327 }
328 
329 static int nvme_configure_admin_queue(struct nvme_dev *dev)
330 {
331 	int result;
332 	u32 aqa;
333 	u64 cap = dev->cap;
334 	struct nvme_queue *nvmeq;
335 	/* most architectures use 4KB as the page size */
336 	unsigned page_shift = 12;
337 	unsigned dev_page_min = NVME_CAP_MPSMIN(cap) + 12;
338 	unsigned dev_page_max = NVME_CAP_MPSMAX(cap) + 12;
339 
340 	if (page_shift < dev_page_min) {
341 		debug("Device minimum page size (%u) too large for host (%u)\n",
342 		      1 << dev_page_min, 1 << page_shift);
343 		return -ENODEV;
344 	}
345 
346 	if (page_shift > dev_page_max) {
347 		debug("Device maximum page size (%u) smaller than host (%u)\n",
348 		      1 << dev_page_max, 1 << page_shift);
349 		page_shift = dev_page_max;
350 	}
351 
352 	result = nvme_disable_ctrl(dev);
353 	if (result < 0)
354 		return result;
355 
356 	nvmeq = dev->queues[NVME_ADMIN_Q];
357 	if (!nvmeq) {
358 		nvmeq = nvme_alloc_queue(dev, 0, NVME_AQ_DEPTH);
359 		if (!nvmeq)
360 			return -ENOMEM;
361 	}
362 
363 	aqa = nvmeq->q_depth - 1;
364 	aqa |= aqa << 16;
365 	aqa |= aqa << 16;
366 
367 	dev->page_size = 1 << page_shift;
368 
369 	dev->ctrl_config = NVME_CC_CSS_NVM;
370 	dev->ctrl_config |= (page_shift - 12) << NVME_CC_MPS_SHIFT;
371 	dev->ctrl_config |= NVME_CC_ARB_RR | NVME_CC_SHN_NONE;
372 	dev->ctrl_config |= NVME_CC_IOSQES | NVME_CC_IOCQES;
373 
374 	writel(aqa, &dev->bar->aqa);
375 	nvme_writeq((ulong)nvmeq->sq_cmds, &dev->bar->asq);
376 	nvme_writeq((ulong)nvmeq->cqes, &dev->bar->acq);
377 
378 	result = nvme_enable_ctrl(dev);
379 	if (result)
380 		goto free_nvmeq;
381 
382 	nvmeq->cq_vector = 0;
383 
384 	nvme_init_queue(dev->queues[NVME_ADMIN_Q], 0);
385 
386 	return result;
387 
388  free_nvmeq:
389 	nvme_free_queues(dev, 0);
390 
391 	return result;
392 }
393 
394 static int nvme_alloc_cq(struct nvme_dev *dev, u16 qid,
395 			    struct nvme_queue *nvmeq)
396 {
397 	struct nvme_command c;
398 	int flags = NVME_QUEUE_PHYS_CONTIG | NVME_CQ_IRQ_ENABLED;
399 
400 	memset(&c, 0, sizeof(c));
401 	c.create_cq.opcode = nvme_admin_create_cq;
402 	c.create_cq.prp1 = cpu_to_le64((ulong)nvmeq->cqes);
403 	c.create_cq.cqid = cpu_to_le16(qid);
404 	c.create_cq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
405 	c.create_cq.cq_flags = cpu_to_le16(flags);
406 	c.create_cq.irq_vector = cpu_to_le16(nvmeq->cq_vector);
407 
408 	return nvme_submit_admin_cmd(dev, &c, NULL);
409 }
410 
411 static int nvme_alloc_sq(struct nvme_dev *dev, u16 qid,
412 			    struct nvme_queue *nvmeq)
413 {
414 	struct nvme_command c;
415 	int flags = NVME_QUEUE_PHYS_CONTIG | NVME_SQ_PRIO_MEDIUM;
416 
417 	memset(&c, 0, sizeof(c));
418 	c.create_sq.opcode = nvme_admin_create_sq;
419 	c.create_sq.prp1 = cpu_to_le64((ulong)nvmeq->sq_cmds);
420 	c.create_sq.sqid = cpu_to_le16(qid);
421 	c.create_sq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
422 	c.create_sq.sq_flags = cpu_to_le16(flags);
423 	c.create_sq.cqid = cpu_to_le16(qid);
424 
425 	return nvme_submit_admin_cmd(dev, &c, NULL);
426 }
427 
428 int nvme_identify(struct nvme_dev *dev, unsigned nsid,
429 		  unsigned cns, dma_addr_t dma_addr)
430 {
431 	struct nvme_command c;
432 	u32 page_size = dev->page_size;
433 	int offset = dma_addr & (page_size - 1);
434 	int length = sizeof(struct nvme_id_ctrl);
435 	int ret;
436 
437 	memset(&c, 0, sizeof(c));
438 	c.identify.opcode = nvme_admin_identify;
439 	c.identify.nsid = cpu_to_le32(nsid);
440 	c.identify.prp1 = cpu_to_le64(dma_addr);
441 
442 	length -= (page_size - offset);
443 	if (length <= 0) {
444 		c.identify.prp2 = 0;
445 	} else {
446 		dma_addr += (page_size - offset);
447 		c.identify.prp2 = cpu_to_le64(dma_addr);
448 	}
449 
450 	c.identify.cns = cpu_to_le32(cns);
451 
452 	ret = nvme_submit_admin_cmd(dev, &c, NULL);
453 	if (!ret)
454 		invalidate_dcache_range(dma_addr,
455 					dma_addr + sizeof(struct nvme_id_ctrl));
456 
457 	return ret;
458 }
459 
460 int nvme_get_features(struct nvme_dev *dev, unsigned fid, unsigned nsid,
461 		      dma_addr_t dma_addr, u32 *result)
462 {
463 	struct nvme_command c;
464 
465 	memset(&c, 0, sizeof(c));
466 	c.features.opcode = nvme_admin_get_features;
467 	c.features.nsid = cpu_to_le32(nsid);
468 	c.features.prp1 = cpu_to_le64(dma_addr);
469 	c.features.fid = cpu_to_le32(fid);
470 
471 	/*
472 	 * TODO: add cache invalidate operation when the size of
473 	 * the DMA buffer is known
474 	 */
475 
476 	return nvme_submit_admin_cmd(dev, &c, result);
477 }
478 
479 int nvme_set_features(struct nvme_dev *dev, unsigned fid, unsigned dword11,
480 		      dma_addr_t dma_addr, u32 *result)
481 {
482 	struct nvme_command c;
483 
484 	memset(&c, 0, sizeof(c));
485 	c.features.opcode = nvme_admin_set_features;
486 	c.features.prp1 = cpu_to_le64(dma_addr);
487 	c.features.fid = cpu_to_le32(fid);
488 	c.features.dword11 = cpu_to_le32(dword11);
489 
490 	/*
491 	 * TODO: add cache flush operation when the size of
492 	 * the DMA buffer is known
493 	 */
494 
495 	return nvme_submit_admin_cmd(dev, &c, result);
496 }
497 
498 static int nvme_create_queue(struct nvme_queue *nvmeq, int qid)
499 {
500 	struct nvme_dev *dev = nvmeq->dev;
501 	int result;
502 
503 	nvmeq->cq_vector = qid - 1;
504 	result = nvme_alloc_cq(dev, qid, nvmeq);
505 	if (result < 0)
506 		goto release_cq;
507 
508 	result = nvme_alloc_sq(dev, qid, nvmeq);
509 	if (result < 0)
510 		goto release_sq;
511 
512 	nvme_init_queue(nvmeq, qid);
513 
514 	return result;
515 
516  release_sq:
517 	nvme_delete_sq(dev, qid);
518  release_cq:
519 	nvme_delete_cq(dev, qid);
520 
521 	return result;
522 }
523 
524 static int nvme_set_queue_count(struct nvme_dev *dev, int count)
525 {
526 	int status;
527 	u32 result;
528 	u32 q_count = (count - 1) | ((count - 1) << 16);
529 
530 	status = nvme_set_features(dev, NVME_FEAT_NUM_QUEUES,
531 			q_count, 0, &result);
532 
533 	if (status < 0)
534 		return status;
535 	if (status > 1)
536 		return 0;
537 
538 	return min(result & 0xffff, result >> 16) + 1;
539 }
540 
541 static void nvme_create_io_queues(struct nvme_dev *dev)
542 {
543 	unsigned int i;
544 
545 	for (i = dev->queue_count; i <= dev->max_qid; i++)
546 		if (!nvme_alloc_queue(dev, i, dev->q_depth))
547 			break;
548 
549 	for (i = dev->online_queues; i <= dev->queue_count - 1; i++)
550 		if (nvme_create_queue(dev->queues[i], i))
551 			break;
552 }
553 
554 static int nvme_setup_io_queues(struct nvme_dev *dev)
555 {
556 	int nr_io_queues;
557 	int result;
558 
559 	nr_io_queues = 1;
560 	result = nvme_set_queue_count(dev, nr_io_queues);
561 	if (result <= 0)
562 		return result;
563 
564 	dev->max_qid = nr_io_queues;
565 
566 	/* Free previously allocated queues */
567 	nvme_free_queues(dev, nr_io_queues + 1);
568 	nvme_create_io_queues(dev);
569 
570 	return 0;
571 }
572 
573 static int nvme_get_info_from_identify(struct nvme_dev *dev)
574 {
575 	ALLOC_CACHE_ALIGN_BUFFER(char, buf, sizeof(struct nvme_id_ctrl));
576 	struct nvme_id_ctrl *ctrl = (struct nvme_id_ctrl *)buf;
577 	int ret;
578 	int shift = NVME_CAP_MPSMIN(dev->cap) + 12;
579 
580 	ret = nvme_identify(dev, 0, 1, (dma_addr_t)ctrl);
581 	if (ret)
582 		return -EIO;
583 
584 	dev->nn = le32_to_cpu(ctrl->nn);
585 	dev->vwc = ctrl->vwc;
586 	memcpy(dev->serial, ctrl->sn, sizeof(ctrl->sn));
587 	memcpy(dev->model, ctrl->mn, sizeof(ctrl->mn));
588 	memcpy(dev->firmware_rev, ctrl->fr, sizeof(ctrl->fr));
589 	if (ctrl->mdts)
590 		dev->max_transfer_shift = (ctrl->mdts + shift);
591 	else {
592 		/*
593 		 * Maximum Data Transfer Size (MDTS) field indicates the maximum
594 		 * data transfer size between the host and the controller. The
595 		 * host should not submit a command that exceeds this transfer
596 		 * size. The value is in units of the minimum memory page size
597 		 * and is reported as a power of two (2^n).
598 		 *
599 		 * The spec also says: a value of 0h indicates no restrictions
600 		 * on transfer size. But in nvme_blk_read/write() below we have
601 		 * the following algorithm for maximum number of logic blocks
602 		 * per transfer:
603 		 *
604 		 * u16 lbas = 1 << (dev->max_transfer_shift - ns->lba_shift);
605 		 *
606 		 * In order for lbas not to overflow, the maximum number is 15
607 		 * which means dev->max_transfer_shift = 15 + 9 (ns->lba_shift).
608 		 * Let's use 20 which provides 1MB size.
609 		 */
610 		dev->max_transfer_shift = 20;
611 	}
612 
613 	return 0;
614 }
615 
616 int nvme_scan_namespace(void)
617 {
618 	struct uclass *uc;
619 	struct udevice *dev;
620 	int ret;
621 
622 	ret = uclass_get(UCLASS_NVME, &uc);
623 	if (ret)
624 		return ret;
625 
626 	uclass_foreach_dev(dev, uc) {
627 		ret = device_probe(dev);
628 		if (ret)
629 			return ret;
630 	}
631 
632 	return 0;
633 }
634 
635 static int nvme_blk_probe(struct udevice *udev)
636 {
637 	struct nvme_dev *ndev = dev_get_priv(udev->parent);
638 	struct blk_desc *desc = dev_get_uclass_platdata(udev);
639 	struct nvme_ns *ns = dev_get_priv(udev);
640 	u8 flbas;
641 	ALLOC_CACHE_ALIGN_BUFFER(char, buf, sizeof(struct nvme_id_ns));
642 	struct nvme_id_ns *id = (struct nvme_id_ns *)buf;
643 	struct pci_child_platdata *pplat;
644 
645 	memset(ns, 0, sizeof(*ns));
646 	ns->dev = ndev;
647 	/* extract the namespace id from the block device name */
648 	ns->ns_id = trailing_strtol(udev->name) + 1;
649 	if (nvme_identify(ndev, ns->ns_id, 0, (dma_addr_t)id))
650 		return -EIO;
651 
652 	flbas = id->flbas & NVME_NS_FLBAS_LBA_MASK;
653 	ns->flbas = flbas;
654 	ns->lba_shift = id->lbaf[flbas].ds;
655 	ns->mode_select_num_blocks = le64_to_cpu(id->nsze);
656 	ns->mode_select_block_len = 1 << ns->lba_shift;
657 	list_add(&ns->list, &ndev->namespaces);
658 
659 	desc->lba = ns->mode_select_num_blocks;
660 	desc->log2blksz = ns->lba_shift;
661 	desc->blksz = 1 << ns->lba_shift;
662 	desc->bdev = udev;
663 	pplat = dev_get_parent_platdata(udev->parent);
664 	sprintf(desc->vendor, "0x%.4x", pplat->vendor);
665 	memcpy(desc->product, ndev->serial, sizeof(ndev->serial));
666 	memcpy(desc->revision, ndev->firmware_rev, sizeof(ndev->firmware_rev));
667 
668 	return 0;
669 }
670 
671 static ulong nvme_blk_rw(struct udevice *udev, lbaint_t blknr,
672 			 lbaint_t blkcnt, void *buffer, bool read)
673 {
674 	struct nvme_ns *ns = dev_get_priv(udev);
675 	struct nvme_dev *dev = ns->dev;
676 	struct nvme_command c;
677 	struct blk_desc *desc = dev_get_uclass_platdata(udev);
678 	int status;
679 	u64 prp2;
680 	u64 total_len = blkcnt << desc->log2blksz;
681 	u64 temp_len = total_len;
682 
683 	u64 slba = blknr;
684 	u16 lbas = 1 << (dev->max_transfer_shift - ns->lba_shift);
685 	u64 total_lbas = blkcnt;
686 
687 	if (!read)
688 		flush_dcache_range((unsigned long)buffer,
689 				   (unsigned long)buffer + total_len);
690 
691 	c.rw.opcode = read ? nvme_cmd_read : nvme_cmd_write;
692 	c.rw.flags = 0;
693 	c.rw.nsid = cpu_to_le32(ns->ns_id);
694 	c.rw.control = 0;
695 	c.rw.dsmgmt = 0;
696 	c.rw.reftag = 0;
697 	c.rw.apptag = 0;
698 	c.rw.appmask = 0;
699 	c.rw.metadata = 0;
700 
701 	while (total_lbas) {
702 		if (total_lbas < lbas) {
703 			lbas = (u16)total_lbas;
704 			total_lbas = 0;
705 		} else {
706 			total_lbas -= lbas;
707 		}
708 
709 		if (nvme_setup_prps(dev, &prp2,
710 				    lbas << ns->lba_shift, (ulong)buffer))
711 			return -EIO;
712 		c.rw.slba = cpu_to_le64(slba);
713 		slba += lbas;
714 		c.rw.length = cpu_to_le16(lbas - 1);
715 		c.rw.prp1 = cpu_to_le64((ulong)buffer);
716 		c.rw.prp2 = cpu_to_le64(prp2);
717 		status = nvme_submit_sync_cmd(dev->queues[NVME_IO_Q],
718 				&c, NULL, IO_TIMEOUT);
719 		if (status)
720 			break;
721 		temp_len -= (u32)lbas << ns->lba_shift;
722 		buffer += lbas << ns->lba_shift;
723 	}
724 
725 	if (read)
726 		invalidate_dcache_range((unsigned long)buffer,
727 					(unsigned long)buffer + total_len);
728 
729 	return (total_len - temp_len) >> desc->log2blksz;
730 }
731 
732 static ulong nvme_blk_read(struct udevice *udev, lbaint_t blknr,
733 			   lbaint_t blkcnt, void *buffer)
734 {
735 	return nvme_blk_rw(udev, blknr, blkcnt, buffer, true);
736 }
737 
738 static ulong nvme_blk_write(struct udevice *udev, lbaint_t blknr,
739 			    lbaint_t blkcnt, const void *buffer)
740 {
741 	return nvme_blk_rw(udev, blknr, blkcnt, (void *)buffer, false);
742 }
743 
744 static const struct blk_ops nvme_blk_ops = {
745 	.read	= nvme_blk_read,
746 	.write	= nvme_blk_write,
747 };
748 
749 U_BOOT_DRIVER(nvme_blk) = {
750 	.name	= "nvme-blk",
751 	.id	= UCLASS_BLK,
752 	.probe	= nvme_blk_probe,
753 	.ops	= &nvme_blk_ops,
754 	.priv_auto_alloc_size = sizeof(struct nvme_ns),
755 };
756 
757 static int nvme_bind(struct udevice *udev)
758 {
759 	static int ndev_num;
760 	char name[20];
761 
762 	sprintf(name, "nvme#%d", ndev_num++);
763 
764 	return device_set_name(udev, name);
765 }
766 
767 static int nvme_probe(struct udevice *udev)
768 {
769 	int ret;
770 	struct nvme_dev *ndev = dev_get_priv(udev);
771 
772 	ndev->instance = trailing_strtol(udev->name);
773 
774 	INIT_LIST_HEAD(&ndev->namespaces);
775 	ndev->bar = dm_pci_map_bar(udev, PCI_BASE_ADDRESS_0,
776 			PCI_REGION_MEM);
777 	if (readl(&ndev->bar->csts) == -1) {
778 		ret = -ENODEV;
779 		printf("Error: %s: Out of memory!\n", udev->name);
780 		goto free_nvme;
781 	}
782 
783 	ndev->queues = malloc(NVME_Q_NUM * sizeof(struct nvme_queue *));
784 	if (!ndev->queues) {
785 		ret = -ENOMEM;
786 		printf("Error: %s: Out of memory!\n", udev->name);
787 		goto free_nvme;
788 	}
789 	memset(ndev->queues, 0, NVME_Q_NUM * sizeof(struct nvme_queue *));
790 
791 	ndev->prp_pool = malloc(MAX_PRP_POOL);
792 	if (!ndev->prp_pool) {
793 		ret = -ENOMEM;
794 		printf("Error: %s: Out of memory!\n", udev->name);
795 		goto free_nvme;
796 	}
797 	ndev->prp_entry_num = MAX_PRP_POOL >> 3;
798 
799 	ndev->cap = nvme_readq(&ndev->bar->cap);
800 	ndev->q_depth = min_t(int, NVME_CAP_MQES(ndev->cap) + 1, NVME_Q_DEPTH);
801 	ndev->db_stride = 1 << NVME_CAP_STRIDE(ndev->cap);
802 	ndev->dbs = ((void __iomem *)ndev->bar) + 4096;
803 
804 	ret = nvme_configure_admin_queue(ndev);
805 	if (ret)
806 		goto free_queue;
807 
808 	ret = nvme_setup_io_queues(ndev);
809 	if (ret)
810 		goto free_queue;
811 
812 	nvme_get_info_from_identify(ndev);
813 
814 	return 0;
815 
816 free_queue:
817 	free((void *)ndev->queues);
818 free_nvme:
819 	return ret;
820 }
821 
822 U_BOOT_DRIVER(nvme) = {
823 	.name	= "nvme",
824 	.id	= UCLASS_NVME,
825 	.bind	= nvme_bind,
826 	.probe	= nvme_probe,
827 	.priv_auto_alloc_size = sizeof(struct nvme_dev),
828 };
829 
830 struct pci_device_id nvme_supported[] = {
831 	{ PCI_DEVICE_CLASS(PCI_CLASS_STORAGE_EXPRESS, ~0) },
832 	{}
833 };
834 
835 U_BOOT_PCI_DEVICE(nvme, nvme_supported);
836