xref: /linux/drivers/gpu/drm/msm/dp/dp_panel.c (revision 6efc0ab3b05de0d7bab8ec0597214e4788251071)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2012-2020, The Linux Foundation. All rights reserved.
4  */
5 
6 #include "dp_panel.h"
7 #include "dp_utils.h"
8 
9 #include <drm/drm_connector.h>
10 #include <drm/drm_edid.h>
11 #include <drm/drm_of.h>
12 #include <drm/drm_print.h>
13 
14 #define DP_MAX_NUM_DP_LANES	4
15 #define DP_LINK_RATE_HBR2	540000 /* kbytes */
16 
17 struct dp_panel_private {
18 	struct device *dev;
19 	struct drm_device *drm_dev;
20 	struct dp_panel dp_panel;
21 	struct drm_dp_aux *aux;
22 	struct dp_link *link;
23 	struct dp_catalog *catalog;
24 	bool panel_on;
25 };
26 
27 static void dp_panel_read_psr_cap(struct dp_panel_private *panel)
28 {
29 	ssize_t rlen;
30 	struct dp_panel *dp_panel;
31 
32 	dp_panel = &panel->dp_panel;
33 
34 	/* edp sink */
35 	if (dp_panel->dpcd[DP_EDP_CONFIGURATION_CAP]) {
36 		rlen = drm_dp_dpcd_read(panel->aux, DP_PSR_SUPPORT,
37 				&dp_panel->psr_cap, sizeof(dp_panel->psr_cap));
38 		if (rlen == sizeof(dp_panel->psr_cap)) {
39 			drm_dbg_dp(panel->drm_dev,
40 				"psr version: 0x%x, psr_cap: 0x%x\n",
41 				dp_panel->psr_cap.version,
42 				dp_panel->psr_cap.capabilities);
43 		} else
44 			DRM_ERROR("failed to read psr info, rlen=%zd\n", rlen);
45 	}
46 }
47 
48 static int dp_panel_read_dpcd(struct dp_panel *dp_panel)
49 {
50 	int rc;
51 	struct dp_panel_private *panel;
52 	struct dp_link_info *link_info;
53 	u8 *dpcd, major, minor;
54 
55 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
56 	dpcd = dp_panel->dpcd;
57 	rc = drm_dp_read_dpcd_caps(panel->aux, dpcd);
58 	if (rc)
59 		return rc;
60 
61 	dp_panel->vsc_sdp_supported = drm_dp_vsc_sdp_supported(panel->aux, dpcd);
62 	link_info = &dp_panel->link_info;
63 	link_info->revision = dpcd[DP_DPCD_REV];
64 	major = (link_info->revision >> 4) & 0x0f;
65 	minor = link_info->revision & 0x0f;
66 
67 	link_info->rate = drm_dp_max_link_rate(dpcd);
68 	link_info->num_lanes = drm_dp_max_lane_count(dpcd);
69 
70 	/* Limit data lanes from data-lanes of endpoint property of dtsi */
71 	if (link_info->num_lanes > dp_panel->max_dp_lanes)
72 		link_info->num_lanes = dp_panel->max_dp_lanes;
73 
74 	/* Limit link rate from link-frequencies of endpoint property of dtsi */
75 	if (link_info->rate > dp_panel->max_dp_link_rate)
76 		link_info->rate = dp_panel->max_dp_link_rate;
77 
78 	drm_dbg_dp(panel->drm_dev, "version: %d.%d\n", major, minor);
79 	drm_dbg_dp(panel->drm_dev, "link_rate=%d\n", link_info->rate);
80 	drm_dbg_dp(panel->drm_dev, "lane_count=%d\n", link_info->num_lanes);
81 
82 	if (drm_dp_enhanced_frame_cap(dpcd))
83 		link_info->capabilities |= DP_LINK_CAP_ENHANCED_FRAMING;
84 
85 	dp_panel_read_psr_cap(panel);
86 
87 	return rc;
88 }
89 
90 static u32 dp_panel_get_supported_bpp(struct dp_panel *dp_panel,
91 		u32 mode_edid_bpp, u32 mode_pclk_khz)
92 {
93 	const struct dp_link_info *link_info;
94 	const u32 max_supported_bpp = 30, min_supported_bpp = 18;
95 	u32 bpp, data_rate_khz;
96 
97 	bpp = min(mode_edid_bpp, max_supported_bpp);
98 
99 	link_info = &dp_panel->link_info;
100 	data_rate_khz = link_info->num_lanes * link_info->rate * 8;
101 
102 	do {
103 		if (mode_pclk_khz * bpp <= data_rate_khz)
104 			return bpp;
105 		bpp -= 6;
106 	} while (bpp > min_supported_bpp);
107 
108 	return min_supported_bpp;
109 }
110 
111 int dp_panel_read_sink_caps(struct dp_panel *dp_panel,
112 	struct drm_connector *connector)
113 {
114 	int rc, bw_code;
115 	int count;
116 	struct dp_panel_private *panel;
117 
118 	if (!dp_panel || !connector) {
119 		DRM_ERROR("invalid input\n");
120 		return -EINVAL;
121 	}
122 
123 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
124 
125 	drm_dbg_dp(panel->drm_dev, "max_lanes=%d max_link_rate=%d\n",
126 		dp_panel->max_dp_lanes, dp_panel->max_dp_link_rate);
127 
128 	rc = dp_panel_read_dpcd(dp_panel);
129 	if (rc) {
130 		DRM_ERROR("read dpcd failed %d\n", rc);
131 		return rc;
132 	}
133 
134 	bw_code = drm_dp_link_rate_to_bw_code(dp_panel->link_info.rate);
135 	if (!is_link_rate_valid(bw_code) ||
136 			!is_lane_count_valid(dp_panel->link_info.num_lanes) ||
137 			(bw_code > dp_panel->max_bw_code)) {
138 		DRM_ERROR("Illegal link rate=%d lane=%d\n", dp_panel->link_info.rate,
139 				dp_panel->link_info.num_lanes);
140 		return -EINVAL;
141 	}
142 
143 	if (drm_dp_is_branch(dp_panel->dpcd)) {
144 		count = drm_dp_read_sink_count(panel->aux);
145 		if (!count) {
146 			panel->link->sink_count = 0;
147 			return -ENOTCONN;
148 		}
149 	}
150 
151 	rc = drm_dp_read_downstream_info(panel->aux, dp_panel->dpcd,
152 					 dp_panel->downstream_ports);
153 	if (rc)
154 		return rc;
155 
156 	drm_edid_free(dp_panel->drm_edid);
157 
158 	dp_panel->drm_edid = drm_edid_read_ddc(connector, &panel->aux->ddc);
159 
160 	drm_edid_connector_update(connector, dp_panel->drm_edid);
161 
162 	if (!dp_panel->drm_edid) {
163 		DRM_ERROR("panel edid read failed\n");
164 		/* check edid read fail is due to unplug */
165 		if (!dp_catalog_link_is_connected(panel->catalog)) {
166 			rc = -ETIMEDOUT;
167 			goto end;
168 		}
169 	}
170 
171 end:
172 	return rc;
173 }
174 
175 u32 dp_panel_get_mode_bpp(struct dp_panel *dp_panel,
176 		u32 mode_edid_bpp, u32 mode_pclk_khz)
177 {
178 	struct dp_panel_private *panel;
179 	u32 bpp;
180 
181 	if (!dp_panel || !mode_edid_bpp || !mode_pclk_khz) {
182 		DRM_ERROR("invalid input\n");
183 		return 0;
184 	}
185 
186 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
187 
188 	if (dp_panel->video_test)
189 		bpp = dp_link_bit_depth_to_bpp(
190 				panel->link->test_video.test_bit_depth);
191 	else
192 		bpp = dp_panel_get_supported_bpp(dp_panel, mode_edid_bpp,
193 				mode_pclk_khz);
194 
195 	return bpp;
196 }
197 
198 int dp_panel_get_modes(struct dp_panel *dp_panel,
199 	struct drm_connector *connector)
200 {
201 	if (!dp_panel) {
202 		DRM_ERROR("invalid input\n");
203 		return -EINVAL;
204 	}
205 
206 	if (dp_panel->drm_edid)
207 		return drm_edid_connector_add_modes(connector);
208 
209 	return 0;
210 }
211 
212 static u8 dp_panel_get_edid_checksum(const struct edid *edid)
213 {
214 	edid += edid->extensions;
215 
216 	return edid->checksum;
217 }
218 
219 void dp_panel_handle_sink_request(struct dp_panel *dp_panel)
220 {
221 	struct dp_panel_private *panel;
222 
223 	if (!dp_panel) {
224 		DRM_ERROR("invalid input\n");
225 		return;
226 	}
227 
228 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
229 
230 	if (panel->link->sink_request & DP_TEST_LINK_EDID_READ) {
231 		/* FIXME: get rid of drm_edid_raw() */
232 		const struct edid *edid = drm_edid_raw(dp_panel->drm_edid);
233 		u8 checksum;
234 
235 		if (edid)
236 			checksum = dp_panel_get_edid_checksum(edid);
237 		else
238 			checksum = dp_panel->connector->real_edid_checksum;
239 
240 		dp_link_send_edid_checksum(panel->link, checksum);
241 		dp_link_send_test_response(panel->link);
242 	}
243 }
244 
245 void dp_panel_tpg_config(struct dp_panel *dp_panel, bool enable)
246 {
247 	struct dp_catalog *catalog;
248 	struct dp_panel_private *panel;
249 
250 	if (!dp_panel) {
251 		DRM_ERROR("invalid input\n");
252 		return;
253 	}
254 
255 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
256 	catalog = panel->catalog;
257 
258 	if (!panel->panel_on) {
259 		drm_dbg_dp(panel->drm_dev,
260 				"DP panel not enabled, handle TPG on next on\n");
261 		return;
262 	}
263 
264 	if (!enable) {
265 		dp_catalog_panel_tpg_disable(catalog);
266 		return;
267 	}
268 
269 	drm_dbg_dp(panel->drm_dev, "calling catalog tpg_enable\n");
270 	dp_catalog_panel_tpg_enable(catalog, &panel->dp_panel.dp_mode.drm_mode);
271 }
272 
273 static int dp_panel_setup_vsc_sdp_yuv_420(struct dp_panel *dp_panel)
274 {
275 	struct dp_catalog *catalog;
276 	struct dp_panel_private *panel;
277 	struct dp_display_mode *dp_mode;
278 	struct drm_dp_vsc_sdp vsc_sdp_data;
279 	struct dp_sdp vsc_sdp;
280 	ssize_t len;
281 
282 	if (!dp_panel) {
283 		DRM_ERROR("invalid input\n");
284 		return -EINVAL;
285 	}
286 
287 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
288 	catalog = panel->catalog;
289 	dp_mode = &dp_panel->dp_mode;
290 
291 	memset(&vsc_sdp_data, 0, sizeof(vsc_sdp_data));
292 
293 	/* VSC SDP header as per table 2-118 of DP 1.4 specification */
294 	vsc_sdp_data.sdp_type = DP_SDP_VSC;
295 	vsc_sdp_data.revision = 0x05;
296 	vsc_sdp_data.length = 0x13;
297 
298 	/* VSC SDP Payload for DB16 */
299 	vsc_sdp_data.pixelformat = DP_PIXELFORMAT_YUV420;
300 	vsc_sdp_data.colorimetry = DP_COLORIMETRY_DEFAULT;
301 
302 	/* VSC SDP Payload for DB17 */
303 	vsc_sdp_data.bpc = dp_mode->bpp / 3;
304 	vsc_sdp_data.dynamic_range = DP_DYNAMIC_RANGE_CTA;
305 
306 	/* VSC SDP Payload for DB18 */
307 	vsc_sdp_data.content_type = DP_CONTENT_TYPE_GRAPHICS;
308 
309 	len = drm_dp_vsc_sdp_pack(&vsc_sdp_data, &vsc_sdp);
310 	if (len < 0) {
311 		DRM_ERROR("unable to pack vsc sdp\n");
312 		return len;
313 	}
314 
315 	dp_catalog_panel_enable_vsc_sdp(catalog, &vsc_sdp);
316 
317 	return 0;
318 }
319 
320 void dp_panel_dump_regs(struct dp_panel *dp_panel)
321 {
322 	struct dp_catalog *catalog;
323 	struct dp_panel_private *panel;
324 
325 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
326 	catalog = panel->catalog;
327 
328 	dp_catalog_dump_regs(catalog);
329 }
330 
331 int dp_panel_timing_cfg(struct dp_panel *dp_panel)
332 {
333 	u32 data, total_ver, total_hor;
334 	struct dp_catalog *catalog;
335 	struct dp_panel_private *panel;
336 	struct drm_display_mode *drm_mode;
337 	u32 width_blanking;
338 	u32 sync_start;
339 	u32 dp_active;
340 	u32 total;
341 
342 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
343 	catalog = panel->catalog;
344 	drm_mode = &panel->dp_panel.dp_mode.drm_mode;
345 
346 	drm_dbg_dp(panel->drm_dev, "width=%d hporch= %d %d %d\n",
347 		drm_mode->hdisplay, drm_mode->htotal - drm_mode->hsync_end,
348 		drm_mode->hsync_start - drm_mode->hdisplay,
349 		drm_mode->hsync_end - drm_mode->hsync_start);
350 
351 	drm_dbg_dp(panel->drm_dev, "height=%d vporch= %d %d %d\n",
352 		drm_mode->vdisplay, drm_mode->vtotal - drm_mode->vsync_end,
353 		drm_mode->vsync_start - drm_mode->vdisplay,
354 		drm_mode->vsync_end - drm_mode->vsync_start);
355 
356 	total_hor = drm_mode->htotal;
357 
358 	total_ver = drm_mode->vtotal;
359 
360 	data = total_ver;
361 	data <<= 16;
362 	data |= total_hor;
363 
364 	total = data;
365 
366 	data = (drm_mode->vtotal - drm_mode->vsync_start);
367 	data <<= 16;
368 	data |= (drm_mode->htotal - drm_mode->hsync_start);
369 
370 	sync_start = data;
371 
372 	data = drm_mode->vsync_end - drm_mode->vsync_start;
373 	data <<= 16;
374 	data |= (panel->dp_panel.dp_mode.v_active_low << 31);
375 	data |= drm_mode->hsync_end - drm_mode->hsync_start;
376 	data |= (panel->dp_panel.dp_mode.h_active_low << 15);
377 
378 	width_blanking = data;
379 
380 	data = drm_mode->vdisplay;
381 	data <<= 16;
382 	data |= drm_mode->hdisplay;
383 
384 	dp_active = data;
385 
386 	dp_catalog_panel_timing_cfg(catalog, total, sync_start, width_blanking, dp_active);
387 
388 	if (dp_panel->dp_mode.out_fmt_is_yuv_420)
389 		dp_panel_setup_vsc_sdp_yuv_420(dp_panel);
390 
391 	panel->panel_on = true;
392 
393 	return 0;
394 }
395 
396 int dp_panel_init_panel_info(struct dp_panel *dp_panel)
397 {
398 	struct drm_display_mode *drm_mode;
399 	struct dp_panel_private *panel;
400 
401 	drm_mode = &dp_panel->dp_mode.drm_mode;
402 
403 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
404 
405 	/*
406 	 * print resolution info as this is a result
407 	 * of user initiated action of cable connection
408 	 */
409 	drm_dbg_dp(panel->drm_dev, "SET NEW RESOLUTION:\n");
410 	drm_dbg_dp(panel->drm_dev, "%dx%d@%dfps\n",
411 		drm_mode->hdisplay, drm_mode->vdisplay, drm_mode_vrefresh(drm_mode));
412 	drm_dbg_dp(panel->drm_dev,
413 			"h_porches(back|front|width) = (%d|%d|%d)\n",
414 			drm_mode->htotal - drm_mode->hsync_end,
415 			drm_mode->hsync_start - drm_mode->hdisplay,
416 			drm_mode->hsync_end - drm_mode->hsync_start);
417 	drm_dbg_dp(panel->drm_dev,
418 			"v_porches(back|front|width) = (%d|%d|%d)\n",
419 			drm_mode->vtotal - drm_mode->vsync_end,
420 			drm_mode->vsync_start - drm_mode->vdisplay,
421 			drm_mode->vsync_end - drm_mode->vsync_start);
422 	drm_dbg_dp(panel->drm_dev, "pixel clock (KHz)=(%d)\n",
423 				drm_mode->clock);
424 	drm_dbg_dp(panel->drm_dev, "bpp = %d\n", dp_panel->dp_mode.bpp);
425 
426 	dp_panel->dp_mode.bpp = dp_panel_get_mode_bpp(dp_panel, dp_panel->dp_mode.bpp,
427 						      dp_panel->dp_mode.drm_mode.clock);
428 
429 	drm_dbg_dp(panel->drm_dev, "updated bpp = %d\n",
430 				dp_panel->dp_mode.bpp);
431 
432 	return 0;
433 }
434 
435 static u32 dp_panel_link_frequencies(struct device_node *of_node)
436 {
437 	struct device_node *endpoint;
438 	u64 frequency = 0;
439 	int cnt;
440 
441 	endpoint = of_graph_get_endpoint_by_regs(of_node, 1, 0); /* port@1 */
442 	if (!endpoint)
443 		return 0;
444 
445 	cnt = of_property_count_u64_elems(endpoint, "link-frequencies");
446 
447 	if (cnt > 0)
448 		of_property_read_u64_index(endpoint, "link-frequencies",
449 						cnt - 1, &frequency);
450 	of_node_put(endpoint);
451 
452 	do_div(frequency,
453 		10 * /* from symbol rate to link rate */
454 		1000); /* kbytes */
455 
456 	return frequency;
457 }
458 
459 static int dp_panel_parse_dt(struct dp_panel *dp_panel)
460 {
461 	struct dp_panel_private *panel;
462 	struct device_node *of_node;
463 	int cnt;
464 
465 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
466 	of_node = panel->dev->of_node;
467 
468 	/*
469 	 * data-lanes is the property of dp_out endpoint
470 	 */
471 	cnt = drm_of_get_data_lanes_count_ep(of_node, 1, 0, 1, DP_MAX_NUM_DP_LANES);
472 	if (cnt < 0) {
473 		/* legacy code, data-lanes is the property of mdss_dp node */
474 		cnt = drm_of_get_data_lanes_count(of_node, 1, DP_MAX_NUM_DP_LANES);
475 	}
476 
477 	if (cnt > 0)
478 		dp_panel->max_dp_lanes = cnt;
479 	else
480 		dp_panel->max_dp_lanes = DP_MAX_NUM_DP_LANES; /* 4 lanes */
481 
482 	dp_panel->max_dp_link_rate = dp_panel_link_frequencies(of_node);
483 	if (!dp_panel->max_dp_link_rate)
484 		dp_panel->max_dp_link_rate = DP_LINK_RATE_HBR2;
485 
486 	return 0;
487 }
488 
489 struct dp_panel *dp_panel_get(struct dp_panel_in *in)
490 {
491 	struct dp_panel_private *panel;
492 	struct dp_panel *dp_panel;
493 	int ret;
494 
495 	if (!in->dev || !in->catalog || !in->aux || !in->link) {
496 		DRM_ERROR("invalid input\n");
497 		return ERR_PTR(-EINVAL);
498 	}
499 
500 	panel = devm_kzalloc(in->dev, sizeof(*panel), GFP_KERNEL);
501 	if (!panel)
502 		return ERR_PTR(-ENOMEM);
503 
504 	panel->dev = in->dev;
505 	panel->aux = in->aux;
506 	panel->catalog = in->catalog;
507 	panel->link = in->link;
508 
509 	dp_panel = &panel->dp_panel;
510 	dp_panel->max_bw_code = DP_LINK_BW_8_1;
511 
512 	ret = dp_panel_parse_dt(dp_panel);
513 	if (ret)
514 		return ERR_PTR(ret);
515 
516 	return dp_panel;
517 }
518 
519 void dp_panel_put(struct dp_panel *dp_panel)
520 {
521 	if (!dp_panel)
522 		return;
523 
524 	drm_edid_free(dp_panel->drm_edid);
525 }
526