1/*
2 * Copyright 2014 Red Hat Inc.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20 * OTHER DEALINGS IN THE SOFTWARE.
21 *
22 * Authors: Ben Skeggs
23 */
24#include "outpdp.h"
25#include "conn.h"
26#include "dport.h"
27#include "priv.h"
28
29#include <subdev/i2c.h>
30
31#include <nvif/event.h>
32
33int
34nvkm_output_dp_train(struct nvkm_output *base, u32 datarate, bool wait)
35{
36	struct nvkm_output_dp *outp = nvkm_output_dp(base);
37	bool retrain = true;
38	u8 link[2], stat[3];
39	u32 linkrate;
40	int ret, i;
41
42	/* check that the link is trained at a high enough rate */
43	ret = nvkm_rdaux(outp->aux, DPCD_LC00_LINK_BW_SET, link, 2);
44	if (ret) {
45		OUTP_DBG(&outp->base,
46			 "failed to read link config, assuming no sink");
47		goto done;
48	}
49
50	linkrate = link[0] * 27000 * (link[1] & DPCD_LC01_LANE_COUNT_SET);
51	linkrate = (linkrate * 8) / 10; /* 8B/10B coding overhead */
52	datarate = (datarate + 9) / 10; /* -> decakilobits */
53	if (linkrate < datarate) {
54		OUTP_DBG(&outp->base, "link not trained at sufficient rate");
55		goto done;
56	}
57
58	/* check that link is still trained */
59	ret = nvkm_rdaux(outp->aux, DPCD_LS02, stat, 3);
60	if (ret) {
61		OUTP_DBG(&outp->base,
62			 "failed to read link status, assuming no sink");
63		goto done;
64	}
65
66	if (stat[2] & DPCD_LS04_INTERLANE_ALIGN_DONE) {
67		for (i = 0; i < (link[1] & DPCD_LC01_LANE_COUNT_SET); i++) {
68			u8 lane = (stat[i >> 1] >> ((i & 1) * 4)) & 0x0f;
69			if (!(lane & DPCD_LS02_LANE0_CR_DONE) ||
70			    !(lane & DPCD_LS02_LANE0_CHANNEL_EQ_DONE) ||
71			    !(lane & DPCD_LS02_LANE0_SYMBOL_LOCKED)) {
72				OUTP_DBG(&outp->base,
73					 "lane %d not equalised", lane);
74				goto done;
75			}
76		}
77		retrain = false;
78	} else {
79		OUTP_DBG(&outp->base, "no inter-lane alignment");
80	}
81
82done:
83	if (retrain || !atomic_read(&outp->lt.done)) {
84		/* no sink, but still need to configure source */
85		if (outp->dpcd[DPCD_RC00_DPCD_REV] == 0x00) {
86			outp->dpcd[DPCD_RC01_MAX_LINK_RATE] =
87				outp->base.info.dpconf.link_bw;
88			outp->dpcd[DPCD_RC02] =
89				outp->base.info.dpconf.link_nr;
90		}
91		atomic_set(&outp->lt.done, 0);
92		schedule_work(&outp->lt.work);
93	} else {
94		nvkm_notify_get(&outp->irq);
95	}
96
97	if (wait) {
98		if (!wait_event_timeout(outp->lt.wait,
99					atomic_read(&outp->lt.done),
100					msecs_to_jiffies(2000)))
101			ret = -ETIMEDOUT;
102	}
103
104	return ret;
105}
106
107static void
108nvkm_output_dp_enable(struct nvkm_output_dp *outp, bool enable)
109{
110	struct nvkm_i2c_aux *aux = outp->aux;
111
112	if (enable) {
113		if (!outp->present) {
114			OUTP_DBG(&outp->base, "aux power -> always");
115			nvkm_i2c_aux_monitor(aux, true);
116			outp->present = true;
117		}
118
119		if (!nvkm_rdaux(aux, DPCD_RC00_DPCD_REV, outp->dpcd,
120				sizeof(outp->dpcd))) {
121			nvkm_output_dp_train(&outp->base, 0, true);
122			return;
123		}
124	}
125
126	if (outp->present) {
127		OUTP_DBG(&outp->base, "aux power -> demand");
128		nvkm_i2c_aux_monitor(aux, false);
129		outp->present = false;
130	}
131
132	atomic_set(&outp->lt.done, 0);
133}
134
135static int
136nvkm_output_dp_hpd(struct nvkm_notify *notify)
137{
138	const struct nvkm_i2c_ntfy_rep *line = notify->data;
139	struct nvkm_output_dp *outp = container_of(notify, typeof(*outp), hpd);
140	struct nvkm_connector *conn = outp->base.conn;
141	struct nvkm_disp *disp = outp->base.disp;
142	struct nvif_notify_conn_rep_v0 rep = {};
143
144	OUTP_DBG(&outp->base, "HPD: %d", line->mask);
145	nvkm_output_dp_enable(outp, true);
146
147	if (line->mask & NVKM_I2C_UNPLUG)
148		rep.mask |= NVIF_NOTIFY_CONN_V0_UNPLUG;
149	if (line->mask & NVKM_I2C_PLUG)
150		rep.mask |= NVIF_NOTIFY_CONN_V0_PLUG;
151
152	nvkm_event_send(&disp->hpd, rep.mask, conn->index, &rep, sizeof(rep));
153	return NVKM_NOTIFY_KEEP;
154}
155
156static int
157nvkm_output_dp_irq(struct nvkm_notify *notify)
158{
159	const struct nvkm_i2c_ntfy_rep *line = notify->data;
160	struct nvkm_output_dp *outp = container_of(notify, typeof(*outp), irq);
161	struct nvkm_connector *conn = outp->base.conn;
162	struct nvkm_disp *disp = outp->base.disp;
163	struct nvif_notify_conn_rep_v0 rep = {
164		.mask = NVIF_NOTIFY_CONN_V0_IRQ,
165	};
166
167	OUTP_DBG(&outp->base, "IRQ: %d", line->mask);
168	nvkm_output_dp_train(&outp->base, 0, true);
169
170	nvkm_event_send(&disp->hpd, rep.mask, conn->index, &rep, sizeof(rep));
171	return NVKM_NOTIFY_DROP;
172}
173
174static void
175nvkm_output_dp_fini(struct nvkm_output *base)
176{
177	struct nvkm_output_dp *outp = nvkm_output_dp(base);
178	nvkm_notify_put(&outp->hpd);
179	nvkm_notify_put(&outp->irq);
180	flush_work(&outp->lt.work);
181	nvkm_output_dp_enable(outp, false);
182}
183
184static void
185nvkm_output_dp_init(struct nvkm_output *base)
186{
187	struct nvkm_output_dp *outp = nvkm_output_dp(base);
188	nvkm_notify_put(&outp->base.conn->hpd);
189	nvkm_output_dp_enable(outp, true);
190	nvkm_notify_get(&outp->hpd);
191}
192
193static void *
194nvkm_output_dp_dtor(struct nvkm_output *base)
195{
196	struct nvkm_output_dp *outp = nvkm_output_dp(base);
197	nvkm_notify_fini(&outp->hpd);
198	nvkm_notify_fini(&outp->irq);
199	return outp;
200}
201
202static const struct nvkm_output_func
203nvkm_output_dp_func = {
204	.dtor = nvkm_output_dp_dtor,
205	.init = nvkm_output_dp_init,
206	.fini = nvkm_output_dp_fini,
207};
208
209int
210nvkm_output_dp_ctor(const struct nvkm_output_dp_func *func,
211		    struct nvkm_disp *disp, int index, struct dcb_output *dcbE,
212		    struct nvkm_i2c_aux *aux, struct nvkm_output_dp *outp)
213{
214	struct nvkm_device *device = disp->engine.subdev.device;
215	struct nvkm_bios *bios = device->bios;
216	struct nvkm_i2c *i2c = device->i2c;
217	u8  hdr, cnt, len;
218	u32 data;
219	int ret;
220
221	nvkm_output_ctor(&nvkm_output_dp_func, disp, index, dcbE, &outp->base);
222	outp->func = func;
223	outp->aux = aux;
224	if (!outp->aux) {
225		OUTP_ERR(&outp->base, "no aux");
226		return -ENODEV;
227	}
228
229	/* bios data is not optional */
230	data = nvbios_dpout_match(bios, outp->base.info.hasht,
231				  outp->base.info.hashm, &outp->version,
232				  &hdr, &cnt, &len, &outp->info);
233	if (!data) {
234		OUTP_ERR(&outp->base, "no bios dp data");
235		return -ENODEV;
236	}
237
238	OUTP_DBG(&outp->base, "bios dp %02x %02x %02x %02x",
239		 outp->version, hdr, cnt, len);
240
241	/* link training */
242	INIT_WORK(&outp->lt.work, nvkm_dp_train);
243	init_waitqueue_head(&outp->lt.wait);
244	atomic_set(&outp->lt.done, 0);
245
246	/* link maintenance */
247	ret = nvkm_notify_init(NULL, &i2c->event, nvkm_output_dp_irq, true,
248			       &(struct nvkm_i2c_ntfy_req) {
249				.mask = NVKM_I2C_IRQ,
250				.port = outp->aux->id,
251			       },
252			       sizeof(struct nvkm_i2c_ntfy_req),
253			       sizeof(struct nvkm_i2c_ntfy_rep),
254			       &outp->irq);
255	if (ret) {
256		OUTP_ERR(&outp->base, "error monitoring aux irq: %d", ret);
257		return ret;
258	}
259
260	/* hotplug detect, replaces gpio-based mechanism with aux events */
261	ret = nvkm_notify_init(NULL, &i2c->event, nvkm_output_dp_hpd, true,
262			       &(struct nvkm_i2c_ntfy_req) {
263				.mask = NVKM_I2C_PLUG | NVKM_I2C_UNPLUG,
264				.port = outp->aux->id,
265			       },
266			       sizeof(struct nvkm_i2c_ntfy_req),
267			       sizeof(struct nvkm_i2c_ntfy_rep),
268			       &outp->hpd);
269	if (ret) {
270		OUTP_ERR(&outp->base, "error monitoring aux hpd: %d", ret);
271		return ret;
272	}
273
274	return 0;
275}
276
277int
278nvkm_output_dp_new_(const struct nvkm_output_dp_func *func,
279		    struct nvkm_disp *disp, int index, struct dcb_output *dcbE,
280		    struct nvkm_output **poutp)
281{
282	struct nvkm_i2c *i2c = disp->engine.subdev.device->i2c;
283	struct nvkm_i2c_aux *aux = nvkm_i2c_aux_find(i2c, dcbE->i2c_index);
284	struct nvkm_output_dp *outp;
285
286	if (!(outp = kzalloc(sizeof(*outp), GFP_KERNEL)))
287		return -ENOMEM;
288	*poutp = &outp->base;
289
290	return nvkm_output_dp_ctor(func, disp, index, dcbE, aux, outp);
291}
292