1// SPDX-License-Identifier: GPL-2.0
2/*
3 * System Control and Management Interface (SCMI) Reset Protocol
4 *
5 * Copyright (C) 2019 ARM Ltd.
6 */
7
8#define pr_fmt(fmt) "SCMI Notifications RESET - " fmt
9
10#include <linux/scmi_protocol.h>
11
12#include "common.h"
13#include "notify.h"
14
15enum scmi_reset_protocol_cmd {
16	RESET_DOMAIN_ATTRIBUTES = 0x3,
17	RESET = 0x4,
18	RESET_NOTIFY = 0x5,
19};
20
21#define NUM_RESET_DOMAIN_MASK	0xffff
22#define RESET_NOTIFY_ENABLE	BIT(0)
23
24struct scmi_msg_resp_reset_domain_attributes {
25	__le32 attributes;
26#define SUPPORTS_ASYNC_RESET(x)		((x) & BIT(31))
27#define SUPPORTS_NOTIFY_RESET(x)	((x) & BIT(30))
28	__le32 latency;
29	    u8 name[SCMI_MAX_STR_SIZE];
30};
31
32struct scmi_msg_reset_domain_reset {
33	__le32 domain_id;
34	__le32 flags;
35#define AUTONOMOUS_RESET	BIT(0)
36#define EXPLICIT_RESET_ASSERT	BIT(1)
37#define ASYNCHRONOUS_RESET	BIT(2)
38	__le32 reset_state;
39#define ARCH_COLD_RESET		0
40};
41
42struct scmi_msg_reset_notify {
43	__le32 id;
44	__le32 event_control;
45#define RESET_TP_NOTIFY_ALL	BIT(0)
46};
47
48struct scmi_reset_issued_notify_payld {
49	__le32 agent_id;
50	__le32 domain_id;
51	__le32 reset_state;
52};
53
54struct reset_dom_info {
55	bool async_reset;
56	bool reset_notify;
57	u32 latency_us;
58	char name[SCMI_MAX_STR_SIZE];
59};
60
61struct scmi_reset_info {
62	u32 version;
63	int num_domains;
64	struct reset_dom_info *dom_info;
65};
66
67static int scmi_reset_attributes_get(const struct scmi_handle *handle,
68				     struct scmi_reset_info *pi)
69{
70	int ret;
71	struct scmi_xfer *t;
72	u32 attr;
73
74	ret = scmi_xfer_get_init(handle, PROTOCOL_ATTRIBUTES,
75				 SCMI_PROTOCOL_RESET, 0, sizeof(attr), &t);
76	if (ret)
77		return ret;
78
79	ret = scmi_do_xfer(handle, t);
80	if (!ret) {
81		attr = get_unaligned_le32(t->rx.buf);
82		pi->num_domains = attr & NUM_RESET_DOMAIN_MASK;
83	}
84
85	scmi_xfer_put(handle, t);
86	return ret;
87}
88
89static int
90scmi_reset_domain_attributes_get(const struct scmi_handle *handle, u32 domain,
91				 struct reset_dom_info *dom_info)
92{
93	int ret;
94	struct scmi_xfer *t;
95	struct scmi_msg_resp_reset_domain_attributes *attr;
96
97	ret = scmi_xfer_get_init(handle, RESET_DOMAIN_ATTRIBUTES,
98				 SCMI_PROTOCOL_RESET, sizeof(domain),
99				 sizeof(*attr), &t);
100	if (ret)
101		return ret;
102
103	put_unaligned_le32(domain, t->tx.buf);
104	attr = t->rx.buf;
105
106	ret = scmi_do_xfer(handle, t);
107	if (!ret) {
108		u32 attributes = le32_to_cpu(attr->attributes);
109
110		dom_info->async_reset = SUPPORTS_ASYNC_RESET(attributes);
111		dom_info->reset_notify = SUPPORTS_NOTIFY_RESET(attributes);
112		dom_info->latency_us = le32_to_cpu(attr->latency);
113		if (dom_info->latency_us == U32_MAX)
114			dom_info->latency_us = 0;
115		strlcpy(dom_info->name, attr->name, SCMI_MAX_STR_SIZE);
116	}
117
118	scmi_xfer_put(handle, t);
119	return ret;
120}
121
122static int scmi_reset_num_domains_get(const struct scmi_handle *handle)
123{
124	struct scmi_reset_info *pi = handle->reset_priv;
125
126	return pi->num_domains;
127}
128
129static char *scmi_reset_name_get(const struct scmi_handle *handle, u32 domain)
130{
131	struct scmi_reset_info *pi = handle->reset_priv;
132	struct reset_dom_info *dom = pi->dom_info + domain;
133
134	return dom->name;
135}
136
137static int scmi_reset_latency_get(const struct scmi_handle *handle, u32 domain)
138{
139	struct scmi_reset_info *pi = handle->reset_priv;
140	struct reset_dom_info *dom = pi->dom_info + domain;
141
142	return dom->latency_us;
143}
144
145static int scmi_domain_reset(const struct scmi_handle *handle, u32 domain,
146			     u32 flags, u32 state)
147{
148	int ret;
149	struct scmi_xfer *t;
150	struct scmi_msg_reset_domain_reset *dom;
151	struct scmi_reset_info *pi = handle->reset_priv;
152	struct reset_dom_info *rdom;
153
154	if (domain >= pi->num_domains)
155		return -EINVAL;
156
157	rdom = pi->dom_info + domain;
158	if (rdom->async_reset)
159		flags |= ASYNCHRONOUS_RESET;
160
161	ret = scmi_xfer_get_init(handle, RESET, SCMI_PROTOCOL_RESET,
162				 sizeof(*dom), 0, &t);
163	if (ret)
164		return ret;
165
166	dom = t->tx.buf;
167	dom->domain_id = cpu_to_le32(domain);
168	dom->flags = cpu_to_le32(flags);
169	dom->reset_state = cpu_to_le32(state);
170
171	if (rdom->async_reset)
172		ret = scmi_do_xfer_with_response(handle, t);
173	else
174		ret = scmi_do_xfer(handle, t);
175
176	scmi_xfer_put(handle, t);
177	return ret;
178}
179
180static int scmi_reset_domain_reset(const struct scmi_handle *handle, u32 domain)
181{
182	return scmi_domain_reset(handle, domain, AUTONOMOUS_RESET,
183				 ARCH_COLD_RESET);
184}
185
186static int
187scmi_reset_domain_assert(const struct scmi_handle *handle, u32 domain)
188{
189	return scmi_domain_reset(handle, domain, EXPLICIT_RESET_ASSERT,
190				 ARCH_COLD_RESET);
191}
192
193static int
194scmi_reset_domain_deassert(const struct scmi_handle *handle, u32 domain)
195{
196	return scmi_domain_reset(handle, domain, 0, ARCH_COLD_RESET);
197}
198
199static const struct scmi_reset_ops reset_ops = {
200	.num_domains_get = scmi_reset_num_domains_get,
201	.name_get = scmi_reset_name_get,
202	.latency_get = scmi_reset_latency_get,
203	.reset = scmi_reset_domain_reset,
204	.assert = scmi_reset_domain_assert,
205	.deassert = scmi_reset_domain_deassert,
206};
207
208static int scmi_reset_notify(const struct scmi_handle *handle, u32 domain_id,
209			     bool enable)
210{
211	int ret;
212	u32 evt_cntl = enable ? RESET_TP_NOTIFY_ALL : 0;
213	struct scmi_xfer *t;
214	struct scmi_msg_reset_notify *cfg;
215
216	ret = scmi_xfer_get_init(handle, RESET_NOTIFY,
217				 SCMI_PROTOCOL_RESET, sizeof(*cfg), 0, &t);
218	if (ret)
219		return ret;
220
221	cfg = t->tx.buf;
222	cfg->id = cpu_to_le32(domain_id);
223	cfg->event_control = cpu_to_le32(evt_cntl);
224
225	ret = scmi_do_xfer(handle, t);
226
227	scmi_xfer_put(handle, t);
228	return ret;
229}
230
231static int scmi_reset_set_notify_enabled(const struct scmi_handle *handle,
232					 u8 evt_id, u32 src_id, bool enable)
233{
234	int ret;
235
236	ret = scmi_reset_notify(handle, src_id, enable);
237	if (ret)
238		pr_debug("FAIL_ENABLED - evt[%X] dom[%d] - ret:%d\n",
239			 evt_id, src_id, ret);
240
241	return ret;
242}
243
244static void *scmi_reset_fill_custom_report(const struct scmi_handle *handle,
245					   u8 evt_id, ktime_t timestamp,
246					   const void *payld, size_t payld_sz,
247					   void *report, u32 *src_id)
248{
249	const struct scmi_reset_issued_notify_payld *p = payld;
250	struct scmi_reset_issued_report *r = report;
251
252	if (evt_id != SCMI_EVENT_RESET_ISSUED || sizeof(*p) != payld_sz)
253		return NULL;
254
255	r->timestamp = timestamp;
256	r->agent_id = le32_to_cpu(p->agent_id);
257	r->domain_id = le32_to_cpu(p->domain_id);
258	r->reset_state = le32_to_cpu(p->reset_state);
259	*src_id = r->domain_id;
260
261	return r;
262}
263
264static const struct scmi_event reset_events[] = {
265	{
266		.id = SCMI_EVENT_RESET_ISSUED,
267		.max_payld_sz = sizeof(struct scmi_reset_issued_notify_payld),
268		.max_report_sz = sizeof(struct scmi_reset_issued_report),
269	},
270};
271
272static const struct scmi_event_ops reset_event_ops = {
273	.set_notify_enabled = scmi_reset_set_notify_enabled,
274	.fill_custom_report = scmi_reset_fill_custom_report,
275};
276
277static int scmi_reset_protocol_init(struct scmi_handle *handle)
278{
279	int domain;
280	u32 version;
281	struct scmi_reset_info *pinfo;
282
283	scmi_version_get(handle, SCMI_PROTOCOL_RESET, &version);
284
285	dev_dbg(handle->dev, "Reset Version %d.%d\n",
286		PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
287
288	pinfo = devm_kzalloc(handle->dev, sizeof(*pinfo), GFP_KERNEL);
289	if (!pinfo)
290		return -ENOMEM;
291
292	scmi_reset_attributes_get(handle, pinfo);
293
294	pinfo->dom_info = devm_kcalloc(handle->dev, pinfo->num_domains,
295				       sizeof(*pinfo->dom_info), GFP_KERNEL);
296	if (!pinfo->dom_info)
297		return -ENOMEM;
298
299	for (domain = 0; domain < pinfo->num_domains; domain++) {
300		struct reset_dom_info *dom = pinfo->dom_info + domain;
301
302		scmi_reset_domain_attributes_get(handle, domain, dom);
303	}
304
305	scmi_register_protocol_events(handle,
306				      SCMI_PROTOCOL_RESET, SCMI_PROTO_QUEUE_SZ,
307				      &reset_event_ops, reset_events,
308				      ARRAY_SIZE(reset_events),
309				      pinfo->num_domains);
310
311	pinfo->version = version;
312	handle->reset_ops = &reset_ops;
313	handle->reset_priv = pinfo;
314
315	return 0;
316}
317
318DEFINE_SCMI_PROTOCOL_REGISTER_UNREGISTER(SCMI_PROTOCOL_RESET, reset)
319