xref: /openbmc/linux/drivers/gpu/drm/msm/dp/dp_panel.c (revision 83146efc)
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 
8 #include <drm/drm_connector.h>
9 #include <drm/drm_edid.h>
10 #include <drm/drm_print.h>
11 
12 struct dp_panel_private {
13 	struct device *dev;
14 	struct drm_device *drm_dev;
15 	struct dp_panel dp_panel;
16 	struct drm_dp_aux *aux;
17 	struct dp_link *link;
18 	struct dp_catalog *catalog;
19 	bool panel_on;
20 	bool aux_cfg_update_done;
21 };
22 
23 static void dp_panel_read_psr_cap(struct dp_panel_private *panel)
24 {
25 	ssize_t rlen;
26 	struct dp_panel *dp_panel;
27 
28 	dp_panel = &panel->dp_panel;
29 
30 	/* edp sink */
31 	if (dp_panel->dpcd[DP_EDP_CONFIGURATION_CAP]) {
32 		rlen = drm_dp_dpcd_read(panel->aux, DP_PSR_SUPPORT,
33 				&dp_panel->psr_cap, sizeof(dp_panel->psr_cap));
34 		if (rlen == sizeof(dp_panel->psr_cap)) {
35 			drm_dbg_dp(panel->drm_dev,
36 				"psr version: 0x%x, psr_cap: 0x%x\n",
37 				dp_panel->psr_cap.version,
38 				dp_panel->psr_cap.capabilities);
39 		} else
40 			DRM_ERROR("failed to read psr info, rlen=%zd\n", rlen);
41 	}
42 }
43 
44 static int dp_panel_read_dpcd(struct dp_panel *dp_panel)
45 {
46 	int rc = 0;
47 	size_t len;
48 	ssize_t rlen;
49 	struct dp_panel_private *panel;
50 	struct dp_link_info *link_info;
51 	u8 *dpcd, major = 0, minor = 0, temp;
52 	u32 offset = DP_DPCD_REV;
53 
54 	dpcd = dp_panel->dpcd;
55 
56 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
57 	link_info = &dp_panel->link_info;
58 
59 	rlen = drm_dp_dpcd_read(panel->aux, offset,
60 			dpcd, (DP_RECEIVER_CAP_SIZE + 1));
61 	if (rlen < (DP_RECEIVER_CAP_SIZE + 1)) {
62 		DRM_ERROR("dpcd read failed, rlen=%zd\n", rlen);
63 		if (rlen == -ETIMEDOUT)
64 			rc = rlen;
65 		else
66 			rc = -EINVAL;
67 
68 		goto end;
69 	}
70 
71 	temp = dpcd[DP_TRAINING_AUX_RD_INTERVAL];
72 
73 	/* check for EXTENDED_RECEIVER_CAPABILITY_FIELD_PRESENT */
74 	if (temp & BIT(7)) {
75 		drm_dbg_dp(panel->drm_dev,
76 				"using EXTENDED_RECEIVER_CAPABILITY_FIELD\n");
77 		offset = DPRX_EXTENDED_DPCD_FIELD;
78 	}
79 
80 	rlen = drm_dp_dpcd_read(panel->aux, offset,
81 		dpcd, (DP_RECEIVER_CAP_SIZE + 1));
82 	if (rlen < (DP_RECEIVER_CAP_SIZE + 1)) {
83 		DRM_ERROR("dpcd read failed, rlen=%zd\n", rlen);
84 		if (rlen == -ETIMEDOUT)
85 			rc = rlen;
86 		else
87 			rc = -EINVAL;
88 
89 		goto end;
90 	}
91 
92 	link_info->revision = dpcd[DP_DPCD_REV];
93 	major = (link_info->revision >> 4) & 0x0f;
94 	minor = link_info->revision & 0x0f;
95 
96 	link_info->rate = drm_dp_bw_code_to_link_rate(dpcd[DP_MAX_LINK_RATE]);
97 	link_info->num_lanes = dpcd[DP_MAX_LANE_COUNT] & DP_MAX_LANE_COUNT_MASK;
98 
99 	/* Limit data lanes from data-lanes of endpoint property of dtsi */
100 	if (link_info->num_lanes > dp_panel->max_dp_lanes)
101 		link_info->num_lanes = dp_panel->max_dp_lanes;
102 
103 	/* Limit link rate from link-frequencies of endpoint property of dtsi */
104 	if (link_info->rate > dp_panel->max_dp_link_rate)
105 		link_info->rate = dp_panel->max_dp_link_rate;
106 
107 	drm_dbg_dp(panel->drm_dev, "version: %d.%d\n", major, minor);
108 	drm_dbg_dp(panel->drm_dev, "link_rate=%d\n", link_info->rate);
109 	drm_dbg_dp(panel->drm_dev, "lane_count=%d\n", link_info->num_lanes);
110 
111 	if (drm_dp_enhanced_frame_cap(dpcd))
112 		link_info->capabilities |= DP_LINK_CAP_ENHANCED_FRAMING;
113 
114 	dp_panel->dfp_present = dpcd[DP_DOWNSTREAMPORT_PRESENT];
115 	dp_panel->dfp_present &= DP_DWN_STRM_PORT_PRESENT;
116 
117 	if (dp_panel->dfp_present && (dpcd[DP_DPCD_REV] > 0x10)) {
118 		dp_panel->ds_port_cnt = dpcd[DP_DOWN_STREAM_PORT_COUNT];
119 		dp_panel->ds_port_cnt &= DP_PORT_COUNT_MASK;
120 		len = DP_DOWNSTREAM_PORTS * DP_DOWNSTREAM_CAP_SIZE;
121 
122 		rlen = drm_dp_dpcd_read(panel->aux,
123 			DP_DOWNSTREAM_PORT_0, dp_panel->ds_cap_info, len);
124 		if (rlen < len) {
125 			DRM_ERROR("ds port status failed, rlen=%zd\n", rlen);
126 			rc = -EINVAL;
127 			goto end;
128 		}
129 	}
130 
131 	dp_panel_read_psr_cap(panel);
132 end:
133 	return rc;
134 }
135 
136 static u32 dp_panel_get_supported_bpp(struct dp_panel *dp_panel,
137 		u32 mode_edid_bpp, u32 mode_pclk_khz)
138 {
139 	struct dp_link_info *link_info;
140 	const u32 max_supported_bpp = 30, min_supported_bpp = 18;
141 	u32 bpp = 0, data_rate_khz = 0;
142 
143 	bpp = min_t(u32, mode_edid_bpp, max_supported_bpp);
144 
145 	link_info = &dp_panel->link_info;
146 	data_rate_khz = link_info->num_lanes * link_info->rate * 8;
147 
148 	while (bpp > min_supported_bpp) {
149 		if (mode_pclk_khz * bpp <= data_rate_khz)
150 			break;
151 		bpp -= 6;
152 	}
153 
154 	return bpp;
155 }
156 
157 static int dp_panel_update_modes(struct drm_connector *connector,
158 	struct edid *edid)
159 {
160 	int rc = 0;
161 
162 	if (edid) {
163 		rc = drm_connector_update_edid_property(connector, edid);
164 		if (rc) {
165 			DRM_ERROR("failed to update edid property %d\n", rc);
166 			return rc;
167 		}
168 		rc = drm_add_edid_modes(connector, edid);
169 		return rc;
170 	}
171 
172 	rc = drm_connector_update_edid_property(connector, NULL);
173 	if (rc)
174 		DRM_ERROR("failed to update edid property %d\n", rc);
175 
176 	return rc;
177 }
178 
179 int dp_panel_read_sink_caps(struct dp_panel *dp_panel,
180 	struct drm_connector *connector)
181 {
182 	int rc = 0, bw_code;
183 	int rlen, count;
184 	struct dp_panel_private *panel;
185 
186 	if (!dp_panel || !connector) {
187 		DRM_ERROR("invalid input\n");
188 		return -EINVAL;
189 	}
190 
191 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
192 
193 	rc = dp_panel_read_dpcd(dp_panel);
194 	if (rc) {
195 		DRM_ERROR("read dpcd failed %d\n", rc);
196 		return rc;
197 	}
198 
199 	bw_code = drm_dp_link_rate_to_bw_code(dp_panel->link_info.rate);
200 	if (!is_link_rate_valid(bw_code) ||
201 			!is_lane_count_valid(dp_panel->link_info.num_lanes) ||
202 			(bw_code > dp_panel->max_bw_code)) {
203 		DRM_ERROR("Illegal link rate=%d lane=%d\n", dp_panel->link_info.rate,
204 				dp_panel->link_info.num_lanes);
205 		return -EINVAL;
206 	}
207 
208 	if (dp_panel->dfp_present) {
209 		rlen = drm_dp_dpcd_read(panel->aux, DP_SINK_COUNT,
210 				&count, 1);
211 		if (rlen == 1) {
212 			count = DP_GET_SINK_COUNT(count);
213 			if (!count) {
214 				DRM_ERROR("no downstream ports connected\n");
215 				panel->link->sink_count = 0;
216 				rc = -ENOTCONN;
217 				goto end;
218 			}
219 		}
220 	}
221 
222 	kfree(dp_panel->edid);
223 	dp_panel->edid = NULL;
224 
225 	dp_panel->edid = drm_get_edid(connector,
226 					      &panel->aux->ddc);
227 	if (!dp_panel->edid) {
228 		DRM_ERROR("panel edid read failed\n");
229 		/* check edid read fail is due to unplug */
230 		if (!dp_catalog_link_is_connected(panel->catalog)) {
231 			rc = -ETIMEDOUT;
232 			goto end;
233 		}
234 	}
235 
236 	if (panel->aux_cfg_update_done) {
237 		drm_dbg_dp(panel->drm_dev,
238 				"read DPCD with updated AUX config\n");
239 		rc = dp_panel_read_dpcd(dp_panel);
240 		bw_code = drm_dp_link_rate_to_bw_code(dp_panel->link_info.rate);
241 		if (rc || !is_link_rate_valid(bw_code) ||
242 			!is_lane_count_valid(dp_panel->link_info.num_lanes)
243 			|| (bw_code > dp_panel->max_bw_code)) {
244 			DRM_ERROR("read dpcd failed %d\n", rc);
245 			return rc;
246 		}
247 		panel->aux_cfg_update_done = false;
248 	}
249 end:
250 	return rc;
251 }
252 
253 u32 dp_panel_get_mode_bpp(struct dp_panel *dp_panel,
254 		u32 mode_edid_bpp, u32 mode_pclk_khz)
255 {
256 	struct dp_panel_private *panel;
257 	u32 bpp;
258 
259 	if (!dp_panel || !mode_edid_bpp || !mode_pclk_khz) {
260 		DRM_ERROR("invalid input\n");
261 		return 0;
262 	}
263 
264 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
265 
266 	if (dp_panel->video_test)
267 		bpp = dp_link_bit_depth_to_bpp(
268 				panel->link->test_video.test_bit_depth);
269 	else
270 		bpp = dp_panel_get_supported_bpp(dp_panel, mode_edid_bpp,
271 				mode_pclk_khz);
272 
273 	return bpp;
274 }
275 
276 int dp_panel_get_modes(struct dp_panel *dp_panel,
277 	struct drm_connector *connector)
278 {
279 	if (!dp_panel) {
280 		DRM_ERROR("invalid input\n");
281 		return -EINVAL;
282 	}
283 
284 	if (dp_panel->edid)
285 		return dp_panel_update_modes(connector, dp_panel->edid);
286 
287 	return 0;
288 }
289 
290 static u8 dp_panel_get_edid_checksum(struct edid *edid)
291 {
292 	edid += edid->extensions;
293 
294 	return edid->checksum;
295 }
296 
297 void dp_panel_handle_sink_request(struct dp_panel *dp_panel)
298 {
299 	struct dp_panel_private *panel;
300 
301 	if (!dp_panel) {
302 		DRM_ERROR("invalid input\n");
303 		return;
304 	}
305 
306 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
307 
308 	if (panel->link->sink_request & DP_TEST_LINK_EDID_READ) {
309 		u8 checksum;
310 
311 		if (dp_panel->edid)
312 			checksum = dp_panel_get_edid_checksum(dp_panel->edid);
313 		else
314 			checksum = dp_panel->connector->real_edid_checksum;
315 
316 		dp_link_send_edid_checksum(panel->link, checksum);
317 		dp_link_send_test_response(panel->link);
318 	}
319 }
320 
321 void dp_panel_tpg_config(struct dp_panel *dp_panel, bool enable)
322 {
323 	struct dp_catalog *catalog;
324 	struct dp_panel_private *panel;
325 
326 	if (!dp_panel) {
327 		DRM_ERROR("invalid input\n");
328 		return;
329 	}
330 
331 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
332 	catalog = panel->catalog;
333 
334 	if (!panel->panel_on) {
335 		drm_dbg_dp(panel->drm_dev,
336 				"DP panel not enabled, handle TPG on next on\n");
337 		return;
338 	}
339 
340 	if (!enable) {
341 		dp_catalog_panel_tpg_disable(catalog);
342 		return;
343 	}
344 
345 	drm_dbg_dp(panel->drm_dev, "calling catalog tpg_enable\n");
346 	dp_catalog_panel_tpg_enable(catalog, &panel->dp_panel.dp_mode.drm_mode);
347 }
348 
349 void dp_panel_dump_regs(struct dp_panel *dp_panel)
350 {
351 	struct dp_catalog *catalog;
352 	struct dp_panel_private *panel;
353 
354 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
355 	catalog = panel->catalog;
356 
357 	dp_catalog_dump_regs(catalog);
358 }
359 
360 int dp_panel_timing_cfg(struct dp_panel *dp_panel)
361 {
362 	u32 data, total_ver, total_hor;
363 	struct dp_catalog *catalog;
364 	struct dp_panel_private *panel;
365 	struct drm_display_mode *drm_mode;
366 
367 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
368 	catalog = panel->catalog;
369 	drm_mode = &panel->dp_panel.dp_mode.drm_mode;
370 
371 	drm_dbg_dp(panel->drm_dev, "width=%d hporch= %d %d %d\n",
372 		drm_mode->hdisplay, drm_mode->htotal - drm_mode->hsync_end,
373 		drm_mode->hsync_start - drm_mode->hdisplay,
374 		drm_mode->hsync_end - drm_mode->hsync_start);
375 
376 	drm_dbg_dp(panel->drm_dev, "height=%d vporch= %d %d %d\n",
377 		drm_mode->vdisplay, drm_mode->vtotal - drm_mode->vsync_end,
378 		drm_mode->vsync_start - drm_mode->vdisplay,
379 		drm_mode->vsync_end - drm_mode->vsync_start);
380 
381 	total_hor = drm_mode->htotal;
382 
383 	total_ver = drm_mode->vtotal;
384 
385 	data = total_ver;
386 	data <<= 16;
387 	data |= total_hor;
388 
389 	catalog->total = data;
390 
391 	data = (drm_mode->vtotal - drm_mode->vsync_start);
392 	data <<= 16;
393 	data |= (drm_mode->htotal - drm_mode->hsync_start);
394 
395 	catalog->sync_start = data;
396 
397 	data = drm_mode->vsync_end - drm_mode->vsync_start;
398 	data <<= 16;
399 	data |= (panel->dp_panel.dp_mode.v_active_low << 31);
400 	data |= drm_mode->hsync_end - drm_mode->hsync_start;
401 	data |= (panel->dp_panel.dp_mode.h_active_low << 15);
402 
403 	catalog->width_blanking = data;
404 
405 	data = drm_mode->vdisplay;
406 	data <<= 16;
407 	data |= drm_mode->hdisplay;
408 
409 	catalog->dp_active = data;
410 
411 	dp_catalog_panel_timing_cfg(catalog);
412 	panel->panel_on = true;
413 
414 	return 0;
415 }
416 
417 int dp_panel_init_panel_info(struct dp_panel *dp_panel)
418 {
419 	struct drm_display_mode *drm_mode;
420 	struct dp_panel_private *panel;
421 
422 	drm_mode = &dp_panel->dp_mode.drm_mode;
423 
424 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
425 
426 	/*
427 	 * print resolution info as this is a result
428 	 * of user initiated action of cable connection
429 	 */
430 	drm_dbg_dp(panel->drm_dev, "SET NEW RESOLUTION:\n");
431 	drm_dbg_dp(panel->drm_dev, "%dx%d@%dfps\n",
432 		drm_mode->hdisplay, drm_mode->vdisplay, drm_mode_vrefresh(drm_mode));
433 	drm_dbg_dp(panel->drm_dev,
434 			"h_porches(back|front|width) = (%d|%d|%d)\n",
435 			drm_mode->htotal - drm_mode->hsync_end,
436 			drm_mode->hsync_start - drm_mode->hdisplay,
437 			drm_mode->hsync_end - drm_mode->hsync_start);
438 	drm_dbg_dp(panel->drm_dev,
439 			"v_porches(back|front|width) = (%d|%d|%d)\n",
440 			drm_mode->vtotal - drm_mode->vsync_end,
441 			drm_mode->vsync_start - drm_mode->vdisplay,
442 			drm_mode->vsync_end - drm_mode->vsync_start);
443 	drm_dbg_dp(panel->drm_dev, "pixel clock (KHz)=(%d)\n",
444 				drm_mode->clock);
445 	drm_dbg_dp(panel->drm_dev, "bpp = %d\n", dp_panel->dp_mode.bpp);
446 
447 	dp_panel->dp_mode.bpp = max_t(u32, 18,
448 				min_t(u32, dp_panel->dp_mode.bpp, 30));
449 	drm_dbg_dp(panel->drm_dev, "updated bpp = %d\n",
450 				dp_panel->dp_mode.bpp);
451 
452 	return 0;
453 }
454 
455 struct dp_panel *dp_panel_get(struct dp_panel_in *in)
456 {
457 	struct dp_panel_private *panel;
458 	struct dp_panel *dp_panel;
459 
460 	if (!in->dev || !in->catalog || !in->aux || !in->link) {
461 		DRM_ERROR("invalid input\n");
462 		return ERR_PTR(-EINVAL);
463 	}
464 
465 	panel = devm_kzalloc(in->dev, sizeof(*panel), GFP_KERNEL);
466 	if (!panel)
467 		return ERR_PTR(-ENOMEM);
468 
469 	panel->dev = in->dev;
470 	panel->aux = in->aux;
471 	panel->catalog = in->catalog;
472 	panel->link = in->link;
473 
474 	dp_panel = &panel->dp_panel;
475 	dp_panel->max_bw_code = DP_LINK_BW_8_1;
476 	panel->aux_cfg_update_done = false;
477 
478 	return dp_panel;
479 }
480 
481 void dp_panel_put(struct dp_panel *dp_panel)
482 {
483 	if (!dp_panel)
484 		return;
485 
486 	kfree(dp_panel->edid);
487 }
488