xref: /openbmc/linux/drivers/soc/qcom/rpmh-rsc.c (revision 7c768f84)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2016-2018, The Linux Foundation. All rights reserved.
4  */
5 
6 #define pr_fmt(fmt) "%s " fmt, KBUILD_MODNAME
7 
8 #include <linux/atomic.h>
9 #include <linux/delay.h>
10 #include <linux/interrupt.h>
11 #include <linux/io.h>
12 #include <linux/kernel.h>
13 #include <linux/list.h>
14 #include <linux/of.h>
15 #include <linux/of_irq.h>
16 #include <linux/of_platform.h>
17 #include <linux/platform_device.h>
18 #include <linux/slab.h>
19 #include <linux/spinlock.h>
20 
21 #include <soc/qcom/cmd-db.h>
22 #include <soc/qcom/tcs.h>
23 #include <dt-bindings/soc/qcom,rpmh-rsc.h>
24 
25 #include "rpmh-internal.h"
26 
27 #define CREATE_TRACE_POINTS
28 #include "trace-rpmh.h"
29 
30 #define RSC_DRV_TCS_OFFSET		672
31 #define RSC_DRV_CMD_OFFSET		20
32 
33 /* DRV Configuration Information Register */
34 #define DRV_PRNT_CHLD_CONFIG		0x0C
35 #define DRV_NUM_TCS_MASK		0x3F
36 #define DRV_NUM_TCS_SHIFT		6
37 #define DRV_NCPT_MASK			0x1F
38 #define DRV_NCPT_SHIFT			27
39 
40 /* Register offsets */
41 #define RSC_DRV_IRQ_ENABLE		0x00
42 #define RSC_DRV_IRQ_STATUS		0x04
43 #define RSC_DRV_IRQ_CLEAR		0x08
44 #define RSC_DRV_CMD_WAIT_FOR_CMPL	0x10
45 #define RSC_DRV_CONTROL			0x14
46 #define RSC_DRV_STATUS			0x18
47 #define RSC_DRV_CMD_ENABLE		0x1C
48 #define RSC_DRV_CMD_MSGID		0x30
49 #define RSC_DRV_CMD_ADDR		0x34
50 #define RSC_DRV_CMD_DATA		0x38
51 #define RSC_DRV_CMD_STATUS		0x3C
52 #define RSC_DRV_CMD_RESP_DATA		0x40
53 
54 #define TCS_AMC_MODE_ENABLE		BIT(16)
55 #define TCS_AMC_MODE_TRIGGER		BIT(24)
56 
57 /* TCS CMD register bit mask */
58 #define CMD_MSGID_LEN			8
59 #define CMD_MSGID_RESP_REQ		BIT(8)
60 #define CMD_MSGID_WRITE			BIT(16)
61 #define CMD_STATUS_ISSUED		BIT(8)
62 #define CMD_STATUS_COMPL		BIT(16)
63 
64 static u32 read_tcs_reg(struct rsc_drv *drv, int reg, int tcs_id, int cmd_id)
65 {
66 	return readl_relaxed(drv->tcs_base + reg + RSC_DRV_TCS_OFFSET * tcs_id +
67 			     RSC_DRV_CMD_OFFSET * cmd_id);
68 }
69 
70 static void write_tcs_cmd(struct rsc_drv *drv, int reg, int tcs_id, int cmd_id,
71 			  u32 data)
72 {
73 	writel_relaxed(data, drv->tcs_base + reg + RSC_DRV_TCS_OFFSET * tcs_id +
74 		       RSC_DRV_CMD_OFFSET * cmd_id);
75 }
76 
77 static void write_tcs_reg(struct rsc_drv *drv, int reg, int tcs_id, u32 data)
78 {
79 	writel_relaxed(data, drv->tcs_base + reg + RSC_DRV_TCS_OFFSET * tcs_id);
80 }
81 
82 static void write_tcs_reg_sync(struct rsc_drv *drv, int reg, int tcs_id,
83 			       u32 data)
84 {
85 	writel(data, drv->tcs_base + reg + RSC_DRV_TCS_OFFSET * tcs_id);
86 	for (;;) {
87 		if (data == readl(drv->tcs_base + reg +
88 				  RSC_DRV_TCS_OFFSET * tcs_id))
89 			break;
90 		udelay(1);
91 	}
92 }
93 
94 static bool tcs_is_free(struct rsc_drv *drv, int tcs_id)
95 {
96 	return !test_bit(tcs_id, drv->tcs_in_use) &&
97 	       read_tcs_reg(drv, RSC_DRV_STATUS, tcs_id, 0);
98 }
99 
100 static struct tcs_group *get_tcs_of_type(struct rsc_drv *drv, int type)
101 {
102 	return &drv->tcs[type];
103 }
104 
105 static int tcs_invalidate(struct rsc_drv *drv, int type)
106 {
107 	int m;
108 	struct tcs_group *tcs;
109 
110 	tcs = get_tcs_of_type(drv, type);
111 
112 	spin_lock(&tcs->lock);
113 	if (bitmap_empty(tcs->slots, MAX_TCS_SLOTS)) {
114 		spin_unlock(&tcs->lock);
115 		return 0;
116 	}
117 
118 	for (m = tcs->offset; m < tcs->offset + tcs->num_tcs; m++) {
119 		if (!tcs_is_free(drv, m)) {
120 			spin_unlock(&tcs->lock);
121 			return -EAGAIN;
122 		}
123 		write_tcs_reg_sync(drv, RSC_DRV_CMD_ENABLE, m, 0);
124 	}
125 	bitmap_zero(tcs->slots, MAX_TCS_SLOTS);
126 	spin_unlock(&tcs->lock);
127 
128 	return 0;
129 }
130 
131 /**
132  * rpmh_rsc_invalidate - Invalidate sleep and wake TCSes
133  *
134  * @drv: the RSC controller
135  */
136 int rpmh_rsc_invalidate(struct rsc_drv *drv)
137 {
138 	int ret;
139 
140 	ret = tcs_invalidate(drv, SLEEP_TCS);
141 	if (!ret)
142 		ret = tcs_invalidate(drv, WAKE_TCS);
143 
144 	return ret;
145 }
146 
147 static struct tcs_group *get_tcs_for_msg(struct rsc_drv *drv,
148 					 const struct tcs_request *msg)
149 {
150 	int type, ret;
151 	struct tcs_group *tcs;
152 
153 	switch (msg->state) {
154 	case RPMH_ACTIVE_ONLY_STATE:
155 		type = ACTIVE_TCS;
156 		break;
157 	case RPMH_WAKE_ONLY_STATE:
158 		type = WAKE_TCS;
159 		break;
160 	case RPMH_SLEEP_STATE:
161 		type = SLEEP_TCS;
162 		break;
163 	default:
164 		return ERR_PTR(-EINVAL);
165 	}
166 
167 	/*
168 	 * If we are making an active request on a RSC that does not have a
169 	 * dedicated TCS for active state use, then re-purpose a wake TCS to
170 	 * send active votes.
171 	 * NOTE: The driver must be aware that this RSC does not have a
172 	 * dedicated AMC, and therefore would invalidate the sleep and wake
173 	 * TCSes before making an active state request.
174 	 */
175 	tcs = get_tcs_of_type(drv, type);
176 	if (msg->state == RPMH_ACTIVE_ONLY_STATE && !tcs->num_tcs) {
177 		tcs = get_tcs_of_type(drv, WAKE_TCS);
178 		if (tcs->num_tcs) {
179 			ret = rpmh_rsc_invalidate(drv);
180 			if (ret)
181 				return ERR_PTR(ret);
182 		}
183 	}
184 
185 	return tcs;
186 }
187 
188 static const struct tcs_request *get_req_from_tcs(struct rsc_drv *drv,
189 						  int tcs_id)
190 {
191 	struct tcs_group *tcs;
192 	int i;
193 
194 	for (i = 0; i < TCS_TYPE_NR; i++) {
195 		tcs = &drv->tcs[i];
196 		if (tcs->mask & BIT(tcs_id))
197 			return tcs->req[tcs_id - tcs->offset];
198 	}
199 
200 	return NULL;
201 }
202 
203 /**
204  * tcs_tx_done: TX Done interrupt handler
205  */
206 static irqreturn_t tcs_tx_done(int irq, void *p)
207 {
208 	struct rsc_drv *drv = p;
209 	int i, j, err = 0;
210 	unsigned long irq_status;
211 	const struct tcs_request *req;
212 	struct tcs_cmd *cmd;
213 
214 	irq_status = read_tcs_reg(drv, RSC_DRV_IRQ_STATUS, 0, 0);
215 
216 	for_each_set_bit(i, &irq_status, BITS_PER_LONG) {
217 		req = get_req_from_tcs(drv, i);
218 		if (!req) {
219 			WARN_ON(1);
220 			goto skip;
221 		}
222 
223 		err = 0;
224 		for (j = 0; j < req->num_cmds; j++) {
225 			u32 sts;
226 
227 			cmd = &req->cmds[j];
228 			sts = read_tcs_reg(drv, RSC_DRV_CMD_STATUS, i, j);
229 			if (!(sts & CMD_STATUS_ISSUED) ||
230 			   ((req->wait_for_compl || cmd->wait) &&
231 			   !(sts & CMD_STATUS_COMPL))) {
232 				pr_err("Incomplete request: %s: addr=%#x data=%#x",
233 				       drv->name, cmd->addr, cmd->data);
234 				err = -EIO;
235 			}
236 		}
237 
238 		trace_rpmh_tx_done(drv, i, req, err);
239 skip:
240 		/* Reclaim the TCS */
241 		write_tcs_reg(drv, RSC_DRV_CMD_ENABLE, i, 0);
242 		write_tcs_reg(drv, RSC_DRV_IRQ_CLEAR, 0, BIT(i));
243 		spin_lock(&drv->lock);
244 		clear_bit(i, drv->tcs_in_use);
245 		spin_unlock(&drv->lock);
246 		if (req)
247 			rpmh_tx_done(req, err);
248 	}
249 
250 	return IRQ_HANDLED;
251 }
252 
253 static void __tcs_buffer_write(struct rsc_drv *drv, int tcs_id, int cmd_id,
254 			       const struct tcs_request *msg)
255 {
256 	u32 msgid, cmd_msgid;
257 	u32 cmd_enable = 0;
258 	u32 cmd_complete;
259 	struct tcs_cmd *cmd;
260 	int i, j;
261 
262 	cmd_msgid = CMD_MSGID_LEN;
263 	cmd_msgid |= msg->wait_for_compl ? CMD_MSGID_RESP_REQ : 0;
264 	cmd_msgid |= CMD_MSGID_WRITE;
265 
266 	cmd_complete = read_tcs_reg(drv, RSC_DRV_CMD_WAIT_FOR_CMPL, tcs_id, 0);
267 
268 	for (i = 0, j = cmd_id; i < msg->num_cmds; i++, j++) {
269 		cmd = &msg->cmds[i];
270 		cmd_enable |= BIT(j);
271 		cmd_complete |= cmd->wait << j;
272 		msgid = cmd_msgid;
273 		msgid |= cmd->wait ? CMD_MSGID_RESP_REQ : 0;
274 
275 		write_tcs_cmd(drv, RSC_DRV_CMD_MSGID, tcs_id, j, msgid);
276 		write_tcs_cmd(drv, RSC_DRV_CMD_ADDR, tcs_id, j, cmd->addr);
277 		write_tcs_cmd(drv, RSC_DRV_CMD_DATA, tcs_id, j, cmd->data);
278 		trace_rpmh_send_msg(drv, tcs_id, j, msgid, cmd);
279 	}
280 
281 	write_tcs_reg(drv, RSC_DRV_CMD_WAIT_FOR_CMPL, tcs_id, cmd_complete);
282 	cmd_enable |= read_tcs_reg(drv, RSC_DRV_CMD_ENABLE, tcs_id, 0);
283 	write_tcs_reg(drv, RSC_DRV_CMD_ENABLE, tcs_id, cmd_enable);
284 }
285 
286 static void __tcs_trigger(struct rsc_drv *drv, int tcs_id)
287 {
288 	u32 enable;
289 
290 	/*
291 	 * HW req: Clear the DRV_CONTROL and enable TCS again
292 	 * While clearing ensure that the AMC mode trigger is cleared
293 	 * and then the mode enable is cleared.
294 	 */
295 	enable = read_tcs_reg(drv, RSC_DRV_CONTROL, tcs_id, 0);
296 	enable &= ~TCS_AMC_MODE_TRIGGER;
297 	write_tcs_reg_sync(drv, RSC_DRV_CONTROL, tcs_id, enable);
298 	enable &= ~TCS_AMC_MODE_ENABLE;
299 	write_tcs_reg_sync(drv, RSC_DRV_CONTROL, tcs_id, enable);
300 
301 	/* Enable the AMC mode on the TCS and then trigger the TCS */
302 	enable = TCS_AMC_MODE_ENABLE;
303 	write_tcs_reg_sync(drv, RSC_DRV_CONTROL, tcs_id, enable);
304 	enable |= TCS_AMC_MODE_TRIGGER;
305 	write_tcs_reg_sync(drv, RSC_DRV_CONTROL, tcs_id, enable);
306 }
307 
308 static int check_for_req_inflight(struct rsc_drv *drv, struct tcs_group *tcs,
309 				  const struct tcs_request *msg)
310 {
311 	unsigned long curr_enabled;
312 	u32 addr;
313 	int i, j, k;
314 	int tcs_id = tcs->offset;
315 
316 	for (i = 0; i < tcs->num_tcs; i++, tcs_id++) {
317 		if (tcs_is_free(drv, tcs_id))
318 			continue;
319 
320 		curr_enabled = read_tcs_reg(drv, RSC_DRV_CMD_ENABLE, tcs_id, 0);
321 
322 		for_each_set_bit(j, &curr_enabled, MAX_CMDS_PER_TCS) {
323 			addr = read_tcs_reg(drv, RSC_DRV_CMD_ADDR, tcs_id, j);
324 			for (k = 0; k < msg->num_cmds; k++) {
325 				if (addr == msg->cmds[k].addr)
326 					return -EBUSY;
327 			}
328 		}
329 	}
330 
331 	return 0;
332 }
333 
334 static int find_free_tcs(struct tcs_group *tcs)
335 {
336 	int i;
337 
338 	for (i = 0; i < tcs->num_tcs; i++) {
339 		if (tcs_is_free(tcs->drv, tcs->offset + i))
340 			return tcs->offset + i;
341 	}
342 
343 	return -EBUSY;
344 }
345 
346 static int tcs_write(struct rsc_drv *drv, const struct tcs_request *msg)
347 {
348 	struct tcs_group *tcs;
349 	int tcs_id;
350 	unsigned long flags;
351 	int ret;
352 
353 	tcs = get_tcs_for_msg(drv, msg);
354 	if (IS_ERR(tcs))
355 		return PTR_ERR(tcs);
356 
357 	spin_lock_irqsave(&tcs->lock, flags);
358 	spin_lock(&drv->lock);
359 	/*
360 	 * The h/w does not like if we send a request to the same address,
361 	 * when one is already in-flight or being processed.
362 	 */
363 	ret = check_for_req_inflight(drv, tcs, msg);
364 	if (ret) {
365 		spin_unlock(&drv->lock);
366 		goto done_write;
367 	}
368 
369 	tcs_id = find_free_tcs(tcs);
370 	if (tcs_id < 0) {
371 		ret = tcs_id;
372 		spin_unlock(&drv->lock);
373 		goto done_write;
374 	}
375 
376 	tcs->req[tcs_id - tcs->offset] = msg;
377 	set_bit(tcs_id, drv->tcs_in_use);
378 	spin_unlock(&drv->lock);
379 
380 	__tcs_buffer_write(drv, tcs_id, 0, msg);
381 	__tcs_trigger(drv, tcs_id);
382 
383 done_write:
384 	spin_unlock_irqrestore(&tcs->lock, flags);
385 	return ret;
386 }
387 
388 /**
389  * rpmh_rsc_send_data: Validate the incoming message and write to the
390  * appropriate TCS block.
391  *
392  * @drv: the controller
393  * @msg: the data to be sent
394  *
395  * Return: 0 on success, -EINVAL on error.
396  * Note: This call blocks until a valid data is written to the TCS.
397  */
398 int rpmh_rsc_send_data(struct rsc_drv *drv, const struct tcs_request *msg)
399 {
400 	int ret;
401 
402 	if (!msg || !msg->cmds || !msg->num_cmds ||
403 	    msg->num_cmds > MAX_RPMH_PAYLOAD) {
404 		WARN_ON(1);
405 		return -EINVAL;
406 	}
407 
408 	do {
409 		ret = tcs_write(drv, msg);
410 		if (ret == -EBUSY) {
411 			pr_info_ratelimited("TCS Busy, retrying RPMH message send: addr=%#x\n",
412 					    msg->cmds[0].addr);
413 			udelay(10);
414 		}
415 	} while (ret == -EBUSY);
416 
417 	return ret;
418 }
419 
420 static int find_match(const struct tcs_group *tcs, const struct tcs_cmd *cmd,
421 		      int len)
422 {
423 	int i, j;
424 
425 	/* Check for already cached commands */
426 	for_each_set_bit(i, tcs->slots, MAX_TCS_SLOTS) {
427 		if (tcs->cmd_cache[i] != cmd[0].addr)
428 			continue;
429 		if (i + len >= tcs->num_tcs * tcs->ncpt)
430 			goto seq_err;
431 		for (j = 0; j < len; j++) {
432 			if (tcs->cmd_cache[i + j] != cmd[j].addr)
433 				goto seq_err;
434 		}
435 		return i;
436 	}
437 
438 	return -ENODATA;
439 
440 seq_err:
441 	WARN(1, "Message does not match previous sequence.\n");
442 	return -EINVAL;
443 }
444 
445 static int find_slots(struct tcs_group *tcs, const struct tcs_request *msg,
446 		      int *tcs_id, int *cmd_id)
447 {
448 	int slot, offset;
449 	int i = 0;
450 
451 	/* Find if we already have the msg in our TCS */
452 	slot = find_match(tcs, msg->cmds, msg->num_cmds);
453 	if (slot >= 0)
454 		goto copy_data;
455 
456 	/* Do over, until we can fit the full payload in a TCS */
457 	do {
458 		slot = bitmap_find_next_zero_area(tcs->slots, MAX_TCS_SLOTS,
459 						  i, msg->num_cmds, 0);
460 		if (slot == tcs->num_tcs * tcs->ncpt)
461 			return -ENOMEM;
462 		i += tcs->ncpt;
463 	} while (slot + msg->num_cmds - 1 >= i);
464 
465 copy_data:
466 	bitmap_set(tcs->slots, slot, msg->num_cmds);
467 	/* Copy the addresses of the resources over to the slots */
468 	for (i = 0; i < msg->num_cmds; i++)
469 		tcs->cmd_cache[slot + i] = msg->cmds[i].addr;
470 
471 	offset = slot / tcs->ncpt;
472 	*tcs_id = offset + tcs->offset;
473 	*cmd_id = slot % tcs->ncpt;
474 
475 	return 0;
476 }
477 
478 static int tcs_ctrl_write(struct rsc_drv *drv, const struct tcs_request *msg)
479 {
480 	struct tcs_group *tcs;
481 	int tcs_id = 0, cmd_id = 0;
482 	unsigned long flags;
483 	int ret;
484 
485 	tcs = get_tcs_for_msg(drv, msg);
486 	if (IS_ERR(tcs))
487 		return PTR_ERR(tcs);
488 
489 	spin_lock_irqsave(&tcs->lock, flags);
490 	/* find the TCS id and the command in the TCS to write to */
491 	ret = find_slots(tcs, msg, &tcs_id, &cmd_id);
492 	if (!ret)
493 		__tcs_buffer_write(drv, tcs_id, cmd_id, msg);
494 	spin_unlock_irqrestore(&tcs->lock, flags);
495 
496 	return ret;
497 }
498 
499 /**
500  * rpmh_rsc_write_ctrl_data: Write request to the controller
501  *
502  * @drv: the controller
503  * @msg: the data to be written to the controller
504  *
505  * There is no response returned for writing the request to the controller.
506  */
507 int rpmh_rsc_write_ctrl_data(struct rsc_drv *drv, const struct tcs_request *msg)
508 {
509 	if (!msg || !msg->cmds || !msg->num_cmds ||
510 	    msg->num_cmds > MAX_RPMH_PAYLOAD) {
511 		pr_err("Payload error\n");
512 		return -EINVAL;
513 	}
514 
515 	/* Data sent to this API will not be sent immediately */
516 	if (msg->state == RPMH_ACTIVE_ONLY_STATE)
517 		return -EINVAL;
518 
519 	return tcs_ctrl_write(drv, msg);
520 }
521 
522 static int rpmh_probe_tcs_config(struct platform_device *pdev,
523 				 struct rsc_drv *drv)
524 {
525 	struct tcs_type_config {
526 		u32 type;
527 		u32 n;
528 	} tcs_cfg[TCS_TYPE_NR] = { { 0 } };
529 	struct device_node *dn = pdev->dev.of_node;
530 	u32 config, max_tcs, ncpt, offset;
531 	int i, ret, n, st = 0;
532 	struct tcs_group *tcs;
533 	struct resource *res;
534 	void __iomem *base;
535 	char drv_id[10] = {0};
536 
537 	snprintf(drv_id, ARRAY_SIZE(drv_id), "drv-%d", drv->id);
538 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, drv_id);
539 	base = devm_ioremap_resource(&pdev->dev, res);
540 	if (IS_ERR(base))
541 		return PTR_ERR(base);
542 
543 	ret = of_property_read_u32(dn, "qcom,tcs-offset", &offset);
544 	if (ret)
545 		return ret;
546 	drv->tcs_base = base + offset;
547 
548 	config = readl_relaxed(base + DRV_PRNT_CHLD_CONFIG);
549 
550 	max_tcs = config;
551 	max_tcs &= DRV_NUM_TCS_MASK << (DRV_NUM_TCS_SHIFT * drv->id);
552 	max_tcs = max_tcs >> (DRV_NUM_TCS_SHIFT * drv->id);
553 
554 	ncpt = config & (DRV_NCPT_MASK << DRV_NCPT_SHIFT);
555 	ncpt = ncpt >> DRV_NCPT_SHIFT;
556 
557 	n = of_property_count_u32_elems(dn, "qcom,tcs-config");
558 	if (n != 2 * TCS_TYPE_NR)
559 		return -EINVAL;
560 
561 	for (i = 0; i < TCS_TYPE_NR; i++) {
562 		ret = of_property_read_u32_index(dn, "qcom,tcs-config",
563 						 i * 2, &tcs_cfg[i].type);
564 		if (ret)
565 			return ret;
566 		if (tcs_cfg[i].type >= TCS_TYPE_NR)
567 			return -EINVAL;
568 
569 		ret = of_property_read_u32_index(dn, "qcom,tcs-config",
570 						 i * 2 + 1, &tcs_cfg[i].n);
571 		if (ret)
572 			return ret;
573 		if (tcs_cfg[i].n > MAX_TCS_PER_TYPE)
574 			return -EINVAL;
575 	}
576 
577 	for (i = 0; i < TCS_TYPE_NR; i++) {
578 		tcs = &drv->tcs[tcs_cfg[i].type];
579 		if (tcs->drv)
580 			return -EINVAL;
581 		tcs->drv = drv;
582 		tcs->type = tcs_cfg[i].type;
583 		tcs->num_tcs = tcs_cfg[i].n;
584 		tcs->ncpt = ncpt;
585 		spin_lock_init(&tcs->lock);
586 
587 		if (!tcs->num_tcs || tcs->type == CONTROL_TCS)
588 			continue;
589 
590 		if (st + tcs->num_tcs > max_tcs ||
591 		    st + tcs->num_tcs >= BITS_PER_BYTE * sizeof(tcs->mask))
592 			return -EINVAL;
593 
594 		tcs->mask = ((1 << tcs->num_tcs) - 1) << st;
595 		tcs->offset = st;
596 		st += tcs->num_tcs;
597 
598 		/*
599 		 * Allocate memory to cache sleep and wake requests to
600 		 * avoid reading TCS register memory.
601 		 */
602 		if (tcs->type == ACTIVE_TCS)
603 			continue;
604 
605 		tcs->cmd_cache = devm_kcalloc(&pdev->dev,
606 					      tcs->num_tcs * ncpt, sizeof(u32),
607 					      GFP_KERNEL);
608 		if (!tcs->cmd_cache)
609 			return -ENOMEM;
610 	}
611 
612 	drv->num_tcs = st;
613 
614 	return 0;
615 }
616 
617 static int rpmh_rsc_probe(struct platform_device *pdev)
618 {
619 	struct device_node *dn = pdev->dev.of_node;
620 	struct rsc_drv *drv;
621 	int ret, irq;
622 
623 	/*
624 	 * Even though RPMh doesn't directly use cmd-db, all of its children
625 	 * do. To avoid adding this check to our children we'll do it now.
626 	 */
627 	ret = cmd_db_ready();
628 	if (ret) {
629 		if (ret != -EPROBE_DEFER)
630 			dev_err(&pdev->dev, "Command DB not available (%d)\n",
631 									ret);
632 		return ret;
633 	}
634 
635 	drv = devm_kzalloc(&pdev->dev, sizeof(*drv), GFP_KERNEL);
636 	if (!drv)
637 		return -ENOMEM;
638 
639 	ret = of_property_read_u32(dn, "qcom,drv-id", &drv->id);
640 	if (ret)
641 		return ret;
642 
643 	drv->name = of_get_property(dn, "label", NULL);
644 	if (!drv->name)
645 		drv->name = dev_name(&pdev->dev);
646 
647 	ret = rpmh_probe_tcs_config(pdev, drv);
648 	if (ret)
649 		return ret;
650 
651 	spin_lock_init(&drv->lock);
652 	bitmap_zero(drv->tcs_in_use, MAX_TCS_NR);
653 
654 	irq = platform_get_irq(pdev, drv->id);
655 	if (irq < 0)
656 		return irq;
657 
658 	ret = devm_request_irq(&pdev->dev, irq, tcs_tx_done,
659 			       IRQF_TRIGGER_HIGH | IRQF_NO_SUSPEND,
660 			       drv->name, drv);
661 	if (ret)
662 		return ret;
663 
664 	/* Enable the active TCS to send requests immediately */
665 	write_tcs_reg(drv, RSC_DRV_IRQ_ENABLE, 0, drv->tcs[ACTIVE_TCS].mask);
666 
667 	spin_lock_init(&drv->client.cache_lock);
668 	INIT_LIST_HEAD(&drv->client.cache);
669 	INIT_LIST_HEAD(&drv->client.batch_cache);
670 
671 	dev_set_drvdata(&pdev->dev, drv);
672 
673 	return devm_of_platform_populate(&pdev->dev);
674 }
675 
676 static const struct of_device_id rpmh_drv_match[] = {
677 	{ .compatible = "qcom,rpmh-rsc", },
678 	{ }
679 };
680 
681 static struct platform_driver rpmh_driver = {
682 	.probe = rpmh_rsc_probe,
683 	.driver = {
684 		  .name = "rpmh",
685 		  .of_match_table = rpmh_drv_match,
686 	},
687 };
688 
689 static int __init rpmh_driver_init(void)
690 {
691 	return platform_driver_register(&rpmh_driver);
692 }
693 arch_initcall(rpmh_driver_init);
694