1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2019, Linaro Ltd
4 */
5#include <dt-bindings/power/qcom-aoss-qmp.h>
6#include <linux/clk-provider.h>
7#include <linux/interrupt.h>
8#include <linux/io.h>
9#include <linux/mailbox_client.h>
10#include <linux/module.h>
11#include <linux/platform_device.h>
12#include <linux/pm_domain.h>
13#include <linux/thermal.h>
14#include <linux/slab.h>
15
16#define QMP_DESC_MAGIC			0x0
17#define QMP_DESC_VERSION		0x4
18#define QMP_DESC_FEATURES		0x8
19
20/* AOP-side offsets */
21#define QMP_DESC_UCORE_LINK_STATE	0xc
22#define QMP_DESC_UCORE_LINK_STATE_ACK	0x10
23#define QMP_DESC_UCORE_CH_STATE		0x14
24#define QMP_DESC_UCORE_CH_STATE_ACK	0x18
25#define QMP_DESC_UCORE_MBOX_SIZE	0x1c
26#define QMP_DESC_UCORE_MBOX_OFFSET	0x20
27
28/* Linux-side offsets */
29#define QMP_DESC_MCORE_LINK_STATE	0x24
30#define QMP_DESC_MCORE_LINK_STATE_ACK	0x28
31#define QMP_DESC_MCORE_CH_STATE		0x2c
32#define QMP_DESC_MCORE_CH_STATE_ACK	0x30
33#define QMP_DESC_MCORE_MBOX_SIZE	0x34
34#define QMP_DESC_MCORE_MBOX_OFFSET	0x38
35
36#define QMP_STATE_UP			GENMASK(15, 0)
37#define QMP_STATE_DOWN			GENMASK(31, 16)
38
39#define QMP_MAGIC			0x4d41494c /* mail */
40#define QMP_VERSION			1
41
42/* 64 bytes is enough to store the requests and provides padding to 4 bytes */
43#define QMP_MSG_LEN			64
44
45#define QMP_NUM_COOLING_RESOURCES	2
46
47static bool qmp_cdev_max_state = 1;
48
49struct qmp_cooling_device {
50	struct thermal_cooling_device *cdev;
51	struct qmp *qmp;
52	char *name;
53	bool state;
54};
55
56/**
57 * struct qmp - driver state for QMP implementation
58 * @msgram: iomem referencing the message RAM used for communication
59 * @dev: reference to QMP device
60 * @mbox_client: mailbox client used to ring the doorbell on transmit
61 * @mbox_chan: mailbox channel used to ring the doorbell on transmit
62 * @offset: offset within @msgram where messages should be written
63 * @size: maximum size of the messages to be transmitted
64 * @event: wait_queue for synchronization with the IRQ
65 * @tx_lock: provides synchronization between multiple callers of qmp_send()
66 * @qdss_clk: QDSS clock hw struct
67 * @pd_data: genpd data
68 */
69struct qmp {
70	void __iomem *msgram;
71	struct device *dev;
72
73	struct mbox_client mbox_client;
74	struct mbox_chan *mbox_chan;
75
76	size_t offset;
77	size_t size;
78
79	wait_queue_head_t event;
80
81	struct mutex tx_lock;
82
83	struct clk_hw qdss_clk;
84	struct genpd_onecell_data pd_data;
85	struct qmp_cooling_device *cooling_devs;
86};
87
88struct qmp_pd {
89	struct qmp *qmp;
90	struct generic_pm_domain pd;
91};
92
93#define to_qmp_pd_resource(res) container_of(res, struct qmp_pd, pd)
94
95static void qmp_kick(struct qmp *qmp)
96{
97	mbox_send_message(qmp->mbox_chan, NULL);
98	mbox_client_txdone(qmp->mbox_chan, 0);
99}
100
101static bool qmp_magic_valid(struct qmp *qmp)
102{
103	return readl(qmp->msgram + QMP_DESC_MAGIC) == QMP_MAGIC;
104}
105
106static bool qmp_link_acked(struct qmp *qmp)
107{
108	return readl(qmp->msgram + QMP_DESC_MCORE_LINK_STATE_ACK) == QMP_STATE_UP;
109}
110
111static bool qmp_mcore_channel_acked(struct qmp *qmp)
112{
113	return readl(qmp->msgram + QMP_DESC_MCORE_CH_STATE_ACK) == QMP_STATE_UP;
114}
115
116static bool qmp_ucore_channel_up(struct qmp *qmp)
117{
118	return readl(qmp->msgram + QMP_DESC_UCORE_CH_STATE) == QMP_STATE_UP;
119}
120
121static int qmp_open(struct qmp *qmp)
122{
123	int ret;
124	u32 val;
125
126	if (!qmp_magic_valid(qmp)) {
127		dev_err(qmp->dev, "QMP magic doesn't match\n");
128		return -EINVAL;
129	}
130
131	val = readl(qmp->msgram + QMP_DESC_VERSION);
132	if (val != QMP_VERSION) {
133		dev_err(qmp->dev, "unsupported QMP version %d\n", val);
134		return -EINVAL;
135	}
136
137	qmp->offset = readl(qmp->msgram + QMP_DESC_MCORE_MBOX_OFFSET);
138	qmp->size = readl(qmp->msgram + QMP_DESC_MCORE_MBOX_SIZE);
139	if (!qmp->size) {
140		dev_err(qmp->dev, "invalid mailbox size\n");
141		return -EINVAL;
142	}
143
144	/* Ack remote core's link state */
145	val = readl(qmp->msgram + QMP_DESC_UCORE_LINK_STATE);
146	writel(val, qmp->msgram + QMP_DESC_UCORE_LINK_STATE_ACK);
147
148	/* Set local core's link state to up */
149	writel(QMP_STATE_UP, qmp->msgram + QMP_DESC_MCORE_LINK_STATE);
150
151	qmp_kick(qmp);
152
153	ret = wait_event_timeout(qmp->event, qmp_link_acked(qmp), HZ);
154	if (!ret) {
155		dev_err(qmp->dev, "ucore didn't ack link\n");
156		goto timeout_close_link;
157	}
158
159	writel(QMP_STATE_UP, qmp->msgram + QMP_DESC_MCORE_CH_STATE);
160
161	qmp_kick(qmp);
162
163	ret = wait_event_timeout(qmp->event, qmp_ucore_channel_up(qmp), HZ);
164	if (!ret) {
165		dev_err(qmp->dev, "ucore didn't open channel\n");
166		goto timeout_close_channel;
167	}
168
169	/* Ack remote core's channel state */
170	writel(QMP_STATE_UP, qmp->msgram + QMP_DESC_UCORE_CH_STATE_ACK);
171
172	qmp_kick(qmp);
173
174	ret = wait_event_timeout(qmp->event, qmp_mcore_channel_acked(qmp), HZ);
175	if (!ret) {
176		dev_err(qmp->dev, "ucore didn't ack channel\n");
177		goto timeout_close_channel;
178	}
179
180	return 0;
181
182timeout_close_channel:
183	writel(QMP_STATE_DOWN, qmp->msgram + QMP_DESC_MCORE_CH_STATE);
184
185timeout_close_link:
186	writel(QMP_STATE_DOWN, qmp->msgram + QMP_DESC_MCORE_LINK_STATE);
187	qmp_kick(qmp);
188
189	return -ETIMEDOUT;
190}
191
192static void qmp_close(struct qmp *qmp)
193{
194	writel(QMP_STATE_DOWN, qmp->msgram + QMP_DESC_MCORE_CH_STATE);
195	writel(QMP_STATE_DOWN, qmp->msgram + QMP_DESC_MCORE_LINK_STATE);
196	qmp_kick(qmp);
197}
198
199static irqreturn_t qmp_intr(int irq, void *data)
200{
201	struct qmp *qmp = data;
202
203	wake_up_all(&qmp->event);
204
205	return IRQ_HANDLED;
206}
207
208static bool qmp_message_empty(struct qmp *qmp)
209{
210	return readl(qmp->msgram + qmp->offset) == 0;
211}
212
213/**
214 * qmp_send() - send a message to the AOSS
215 * @qmp: qmp context
216 * @data: message to be sent
217 * @len: length of the message
218 *
219 * Transmit @data to AOSS and wait for the AOSS to acknowledge the message.
220 * @len must be a multiple of 4 and not longer than the mailbox size. Access is
221 * synchronized by this implementation.
222 *
223 * Return: 0 on success, negative errno on failure
224 */
225static int qmp_send(struct qmp *qmp, const void *data, size_t len)
226{
227	long time_left;
228	size_t tlen;
229	int ret;
230
231	if (WARN_ON(len + sizeof(u32) > qmp->size))
232		return -EINVAL;
233
234	if (WARN_ON(len % sizeof(u32)))
235		return -EINVAL;
236
237	mutex_lock(&qmp->tx_lock);
238
239	/* The message RAM only implements 32-bit accesses */
240	__iowrite32_copy(qmp->msgram + qmp->offset + sizeof(u32),
241			 data, len / sizeof(u32));
242	writel(len, qmp->msgram + qmp->offset);
243
244	/* Read back len to confirm data written in message RAM */
245	tlen = readl(qmp->msgram + qmp->offset);
246	qmp_kick(qmp);
247
248	time_left = wait_event_interruptible_timeout(qmp->event,
249						     qmp_message_empty(qmp), HZ);
250	if (!time_left) {
251		dev_err(qmp->dev, "ucore did not ack channel\n");
252		ret = -ETIMEDOUT;
253
254		/* Clear message from buffer */
255		writel(0, qmp->msgram + qmp->offset);
256	} else {
257		ret = 0;
258	}
259
260	mutex_unlock(&qmp->tx_lock);
261
262	return ret;
263}
264
265static int qmp_qdss_clk_prepare(struct clk_hw *hw)
266{
267	static const char buf[QMP_MSG_LEN] = "{class: clock, res: qdss, val: 1}";
268	struct qmp *qmp = container_of(hw, struct qmp, qdss_clk);
269
270	return qmp_send(qmp, buf, sizeof(buf));
271}
272
273static void qmp_qdss_clk_unprepare(struct clk_hw *hw)
274{
275	static const char buf[QMP_MSG_LEN] = "{class: clock, res: qdss, val: 0}";
276	struct qmp *qmp = container_of(hw, struct qmp, qdss_clk);
277
278	qmp_send(qmp, buf, sizeof(buf));
279}
280
281static const struct clk_ops qmp_qdss_clk_ops = {
282	.prepare = qmp_qdss_clk_prepare,
283	.unprepare = qmp_qdss_clk_unprepare,
284};
285
286static int qmp_qdss_clk_add(struct qmp *qmp)
287{
288	static const struct clk_init_data qdss_init = {
289		.ops = &qmp_qdss_clk_ops,
290		.name = "qdss",
291	};
292	int ret;
293
294	qmp->qdss_clk.init = &qdss_init;
295	ret = clk_hw_register(qmp->dev, &qmp->qdss_clk);
296	if (ret < 0) {
297		dev_err(qmp->dev, "failed to register qdss clock\n");
298		return ret;
299	}
300
301	ret = of_clk_add_hw_provider(qmp->dev->of_node, of_clk_hw_simple_get,
302				     &qmp->qdss_clk);
303	if (ret < 0) {
304		dev_err(qmp->dev, "unable to register of clk hw provider\n");
305		clk_hw_unregister(&qmp->qdss_clk);
306	}
307
308	return ret;
309}
310
311static void qmp_qdss_clk_remove(struct qmp *qmp)
312{
313	of_clk_del_provider(qmp->dev->of_node);
314	clk_hw_unregister(&qmp->qdss_clk);
315}
316
317static int qmp_pd_power_toggle(struct qmp_pd *res, bool enable)
318{
319	char buf[QMP_MSG_LEN] = {};
320
321	snprintf(buf, sizeof(buf),
322		 "{class: image, res: load_state, name: %s, val: %s}",
323		 res->pd.name, enable ? "on" : "off");
324	return qmp_send(res->qmp, buf, sizeof(buf));
325}
326
327static int qmp_pd_power_on(struct generic_pm_domain *domain)
328{
329	return qmp_pd_power_toggle(to_qmp_pd_resource(domain), true);
330}
331
332static int qmp_pd_power_off(struct generic_pm_domain *domain)
333{
334	return qmp_pd_power_toggle(to_qmp_pd_resource(domain), false);
335}
336
337static const char * const sdm845_resources[] = {
338	[AOSS_QMP_LS_CDSP] = "cdsp",
339	[AOSS_QMP_LS_LPASS] = "adsp",
340	[AOSS_QMP_LS_MODEM] = "modem",
341	[AOSS_QMP_LS_SLPI] = "slpi",
342	[AOSS_QMP_LS_SPSS] = "spss",
343	[AOSS_QMP_LS_VENUS] = "venus",
344};
345
346static int qmp_pd_add(struct qmp *qmp)
347{
348	struct genpd_onecell_data *data = &qmp->pd_data;
349	struct device *dev = qmp->dev;
350	struct qmp_pd *res;
351	size_t num = ARRAY_SIZE(sdm845_resources);
352	int ret;
353	int i;
354
355	res = devm_kcalloc(dev, num, sizeof(*res), GFP_KERNEL);
356	if (!res)
357		return -ENOMEM;
358
359	data->domains = devm_kcalloc(dev, num, sizeof(*data->domains),
360				     GFP_KERNEL);
361	if (!data->domains)
362		return -ENOMEM;
363
364	for (i = 0; i < num; i++) {
365		res[i].qmp = qmp;
366		res[i].pd.name = sdm845_resources[i];
367		res[i].pd.power_on = qmp_pd_power_on;
368		res[i].pd.power_off = qmp_pd_power_off;
369
370		ret = pm_genpd_init(&res[i].pd, NULL, true);
371		if (ret < 0) {
372			dev_err(dev, "failed to init genpd\n");
373			goto unroll_genpds;
374		}
375
376		data->domains[i] = &res[i].pd;
377	}
378
379	data->num_domains = i;
380
381	ret = of_genpd_add_provider_onecell(dev->of_node, data);
382	if (ret < 0)
383		goto unroll_genpds;
384
385	return 0;
386
387unroll_genpds:
388	for (i--; i >= 0; i--)
389		pm_genpd_remove(data->domains[i]);
390
391	return ret;
392}
393
394static void qmp_pd_remove(struct qmp *qmp)
395{
396	struct genpd_onecell_data *data = &qmp->pd_data;
397	struct device *dev = qmp->dev;
398	int i;
399
400	of_genpd_del_provider(dev->of_node);
401
402	for (i = 0; i < data->num_domains; i++)
403		pm_genpd_remove(data->domains[i]);
404}
405
406static int qmp_cdev_get_max_state(struct thermal_cooling_device *cdev,
407				  unsigned long *state)
408{
409	*state = qmp_cdev_max_state;
410	return 0;
411}
412
413static int qmp_cdev_get_cur_state(struct thermal_cooling_device *cdev,
414				  unsigned long *state)
415{
416	struct qmp_cooling_device *qmp_cdev = cdev->devdata;
417
418	*state = qmp_cdev->state;
419	return 0;
420}
421
422static int qmp_cdev_set_cur_state(struct thermal_cooling_device *cdev,
423				  unsigned long state)
424{
425	struct qmp_cooling_device *qmp_cdev = cdev->devdata;
426	char buf[QMP_MSG_LEN] = {};
427	bool cdev_state;
428	int ret;
429
430	/* Normalize state */
431	cdev_state = !!state;
432
433	if (qmp_cdev->state == state)
434		return 0;
435
436	snprintf(buf, sizeof(buf),
437		 "{class: volt_flr, event:zero_temp, res:%s, value:%s}",
438			qmp_cdev->name,
439			cdev_state ? "on" : "off");
440
441	ret = qmp_send(qmp_cdev->qmp, buf, sizeof(buf));
442
443	if (!ret)
444		qmp_cdev->state = cdev_state;
445
446	return ret;
447}
448
449static struct thermal_cooling_device_ops qmp_cooling_device_ops = {
450	.get_max_state = qmp_cdev_get_max_state,
451	.get_cur_state = qmp_cdev_get_cur_state,
452	.set_cur_state = qmp_cdev_set_cur_state,
453};
454
455static int qmp_cooling_device_add(struct qmp *qmp,
456				  struct qmp_cooling_device *qmp_cdev,
457				  struct device_node *node)
458{
459	char *cdev_name = (char *)node->name;
460
461	qmp_cdev->qmp = qmp;
462	qmp_cdev->state = !qmp_cdev_max_state;
463	qmp_cdev->name = cdev_name;
464	qmp_cdev->cdev = devm_thermal_of_cooling_device_register
465				(qmp->dev, node,
466				cdev_name,
467				qmp_cdev, &qmp_cooling_device_ops);
468
469	if (IS_ERR(qmp_cdev->cdev))
470		dev_err(qmp->dev, "unable to register %s cooling device\n",
471			cdev_name);
472
473	return PTR_ERR_OR_ZERO(qmp_cdev->cdev);
474}
475
476static int qmp_cooling_devices_register(struct qmp *qmp)
477{
478	struct device_node *np, *child;
479	int count = 0;
480	int ret;
481
482	np = qmp->dev->of_node;
483
484	qmp->cooling_devs = devm_kcalloc(qmp->dev, QMP_NUM_COOLING_RESOURCES,
485					 sizeof(*qmp->cooling_devs),
486					 GFP_KERNEL);
487
488	if (!qmp->cooling_devs)
489		return -ENOMEM;
490
491	for_each_available_child_of_node(np, child) {
492		if (!of_find_property(child, "#cooling-cells", NULL))
493			continue;
494		ret = qmp_cooling_device_add(qmp, &qmp->cooling_devs[count++],
495					     child);
496		if (ret) {
497			of_node_put(child);
498			goto unroll;
499		}
500	}
501
502	if (!count)
503		devm_kfree(qmp->dev, qmp->cooling_devs);
504
505	return 0;
506
507unroll:
508	while (--count >= 0)
509		thermal_cooling_device_unregister
510			(qmp->cooling_devs[count].cdev);
511	devm_kfree(qmp->dev, qmp->cooling_devs);
512
513	return ret;
514}
515
516static void qmp_cooling_devices_remove(struct qmp *qmp)
517{
518	int i;
519
520	for (i = 0; i < QMP_NUM_COOLING_RESOURCES; i++)
521		thermal_cooling_device_unregister(qmp->cooling_devs[i].cdev);
522}
523
524static int qmp_probe(struct platform_device *pdev)
525{
526	struct resource *res;
527	struct qmp *qmp;
528	int irq;
529	int ret;
530
531	qmp = devm_kzalloc(&pdev->dev, sizeof(*qmp), GFP_KERNEL);
532	if (!qmp)
533		return -ENOMEM;
534
535	qmp->dev = &pdev->dev;
536	init_waitqueue_head(&qmp->event);
537	mutex_init(&qmp->tx_lock);
538
539	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
540	qmp->msgram = devm_ioremap_resource(&pdev->dev, res);
541	if (IS_ERR(qmp->msgram))
542		return PTR_ERR(qmp->msgram);
543
544	qmp->mbox_client.dev = &pdev->dev;
545	qmp->mbox_client.knows_txdone = true;
546	qmp->mbox_chan = mbox_request_channel(&qmp->mbox_client, 0);
547	if (IS_ERR(qmp->mbox_chan)) {
548		dev_err(&pdev->dev, "failed to acquire ipc mailbox\n");
549		return PTR_ERR(qmp->mbox_chan);
550	}
551
552	irq = platform_get_irq(pdev, 0);
553	ret = devm_request_irq(&pdev->dev, irq, qmp_intr, 0,
554			       "aoss-qmp", qmp);
555	if (ret < 0) {
556		dev_err(&pdev->dev, "failed to request interrupt\n");
557		goto err_free_mbox;
558	}
559
560	ret = qmp_open(qmp);
561	if (ret < 0)
562		goto err_free_mbox;
563
564	ret = qmp_qdss_clk_add(qmp);
565	if (ret)
566		goto err_close_qmp;
567
568	ret = qmp_pd_add(qmp);
569	if (ret)
570		goto err_remove_qdss_clk;
571
572	ret = qmp_cooling_devices_register(qmp);
573	if (ret)
574		dev_err(&pdev->dev, "failed to register aoss cooling devices\n");
575
576	platform_set_drvdata(pdev, qmp);
577
578	return 0;
579
580err_remove_qdss_clk:
581	qmp_qdss_clk_remove(qmp);
582err_close_qmp:
583	qmp_close(qmp);
584err_free_mbox:
585	mbox_free_channel(qmp->mbox_chan);
586
587	return ret;
588}
589
590static int qmp_remove(struct platform_device *pdev)
591{
592	struct qmp *qmp = platform_get_drvdata(pdev);
593
594	qmp_qdss_clk_remove(qmp);
595	qmp_pd_remove(qmp);
596	qmp_cooling_devices_remove(qmp);
597
598	qmp_close(qmp);
599	mbox_free_channel(qmp->mbox_chan);
600
601	return 0;
602}
603
604static const struct of_device_id qmp_dt_match[] = {
605	{ .compatible = "qcom,sc7180-aoss-qmp", },
606	{ .compatible = "qcom,sdm845-aoss-qmp", },
607	{ .compatible = "qcom,sm8150-aoss-qmp", },
608	{ .compatible = "qcom,sm8250-aoss-qmp", },
609	{}
610};
611MODULE_DEVICE_TABLE(of, qmp_dt_match);
612
613static struct platform_driver qmp_driver = {
614	.driver = {
615		.name		= "qcom_aoss_qmp",
616		.of_match_table	= qmp_dt_match,
617	},
618	.probe = qmp_probe,
619	.remove	= qmp_remove,
620};
621module_platform_driver(qmp_driver);
622
623MODULE_DESCRIPTION("Qualcomm AOSS QMP driver");
624MODULE_LICENSE("GPL v2");
625