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 dp_panel dp_panel;
15 	struct drm_dp_aux *aux;
16 	struct dp_link *link;
17 	struct dp_catalog *catalog;
18 	bool panel_on;
19 	bool aux_cfg_update_done;
20 };
21 
dp_panel_read_dpcd(struct dp_panel *dp_panel)22 static int dp_panel_read_dpcd(struct dp_panel *dp_panel)
23 {
24 	int rc = 0;
25 	size_t len;
26 	ssize_t rlen;
27 	struct dp_panel_private *panel;
28 	struct dp_link_info *link_info;
29 	u8 *dpcd, major = 0, minor = 0, temp;
30 	u32 offset = DP_DPCD_REV;
31 
32 	dpcd = dp_panel->dpcd;
33 
34 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
35 	link_info = &dp_panel->link_info;
36 
37 	rlen = drm_dp_dpcd_read(panel->aux, offset,
38 			dpcd, (DP_RECEIVER_CAP_SIZE + 1));
39 	if (rlen < (DP_RECEIVER_CAP_SIZE + 1)) {
40 		DRM_ERROR("dpcd read failed, rlen=%zd\n", rlen);
41 		if (rlen == -ETIMEDOUT)
42 			rc = rlen;
43 		else
44 			rc = -EINVAL;
45 
46 		goto end;
47 	}
48 
49 	temp = dpcd[DP_TRAINING_AUX_RD_INTERVAL];
50 
51 	/* check for EXTENDED_RECEIVER_CAPABILITY_FIELD_PRESENT */
52 	if (temp & BIT(7)) {
53 		DRM_DEBUG_DP("using EXTENDED_RECEIVER_CAPABILITY_FIELD\n");
54 		offset = DPRX_EXTENDED_DPCD_FIELD;
55 	}
56 
57 	rlen = drm_dp_dpcd_read(panel->aux, offset,
58 		dpcd, (DP_RECEIVER_CAP_SIZE + 1));
59 	if (rlen < (DP_RECEIVER_CAP_SIZE + 1)) {
60 		DRM_ERROR("dpcd read failed, rlen=%zd\n", rlen);
61 		if (rlen == -ETIMEDOUT)
62 			rc = rlen;
63 		else
64 			rc = -EINVAL;
65 
66 		goto end;
67 	}
68 
69 	link_info->revision = dpcd[DP_DPCD_REV];
70 	major = (link_info->revision >> 4) & 0x0f;
71 	minor = link_info->revision & 0x0f;
72 
73 	link_info->rate = drm_dp_bw_code_to_link_rate(dpcd[DP_MAX_LINK_RATE]);
74 	link_info->num_lanes = dpcd[DP_MAX_LANE_COUNT] & DP_MAX_LANE_COUNT_MASK;
75 
76 	if (link_info->num_lanes > dp_panel->max_dp_lanes)
77 		link_info->num_lanes = dp_panel->max_dp_lanes;
78 
79 	/* Limit support upto HBR2 until HBR3 support is added */
80 	if (link_info->rate >= (drm_dp_bw_code_to_link_rate(DP_LINK_BW_5_4)))
81 		link_info->rate = drm_dp_bw_code_to_link_rate(DP_LINK_BW_5_4);
82 
83 	DRM_DEBUG_DP("version: %d.%d\n", major, minor);
84 	DRM_DEBUG_DP("link_rate=%d\n", link_info->rate);
85 	DRM_DEBUG_DP("lane_count=%d\n", link_info->num_lanes);
86 
87 	if (drm_dp_enhanced_frame_cap(dpcd))
88 		link_info->capabilities |= DP_LINK_CAP_ENHANCED_FRAMING;
89 
90 	dp_panel->dfp_present = dpcd[DP_DOWNSTREAMPORT_PRESENT];
91 	dp_panel->dfp_present &= DP_DWN_STRM_PORT_PRESENT;
92 
93 	if (dp_panel->dfp_present && (dpcd[DP_DPCD_REV] > 0x10)) {
94 		dp_panel->ds_port_cnt = dpcd[DP_DOWN_STREAM_PORT_COUNT];
95 		dp_panel->ds_port_cnt &= DP_PORT_COUNT_MASK;
96 		len = DP_DOWNSTREAM_PORTS * DP_DOWNSTREAM_CAP_SIZE;
97 
98 		rlen = drm_dp_dpcd_read(panel->aux,
99 			DP_DOWNSTREAM_PORT_0, dp_panel->ds_cap_info, len);
100 		if (rlen < len) {
101 			DRM_ERROR("ds port status failed, rlen=%zd\n", rlen);
102 			rc = -EINVAL;
103 			goto end;
104 		}
105 	}
106 
107 end:
108 	return rc;
109 }
110 
dp_panel_get_supported_bpp(struct dp_panel *dp_panel, u32 mode_edid_bpp, u32 mode_pclk_khz)111 static u32 dp_panel_get_supported_bpp(struct dp_panel *dp_panel,
112 		u32 mode_edid_bpp, u32 mode_pclk_khz)
113 {
114 	struct dp_link_info *link_info;
115 	const u32 max_supported_bpp = 30, min_supported_bpp = 18;
116 	u32 bpp = 0, data_rate_khz = 0;
117 
118 	bpp = min_t(u32, mode_edid_bpp, max_supported_bpp);
119 
120 	link_info = &dp_panel->link_info;
121 	data_rate_khz = link_info->num_lanes * link_info->rate * 8;
122 
123 	while (bpp > min_supported_bpp) {
124 		if (mode_pclk_khz * bpp <= data_rate_khz)
125 			break;
126 		bpp -= 6;
127 	}
128 
129 	return bpp;
130 }
131 
dp_panel_update_modes(struct drm_connector *connector, struct edid *edid)132 static int dp_panel_update_modes(struct drm_connector *connector,
133 	struct edid *edid)
134 {
135 	int rc = 0;
136 
137 	if (edid) {
138 		rc = drm_connector_update_edid_property(connector, edid);
139 		if (rc) {
140 			DRM_ERROR("failed to update edid property %d\n", rc);
141 			return rc;
142 		}
143 		rc = drm_add_edid_modes(connector, edid);
144 		DRM_DEBUG_DP("%s -", __func__);
145 		return rc;
146 	}
147 
148 	rc = drm_connector_update_edid_property(connector, NULL);
149 	if (rc)
150 		DRM_ERROR("failed to update edid property %d\n", rc);
151 
152 	return rc;
153 }
154 
dp_panel_read_sink_caps(struct dp_panel *dp_panel, struct drm_connector *connector)155 int dp_panel_read_sink_caps(struct dp_panel *dp_panel,
156 	struct drm_connector *connector)
157 {
158 	int rc = 0, bw_code;
159 	int rlen, count;
160 	struct dp_panel_private *panel;
161 
162 	if (!dp_panel || !connector) {
163 		DRM_ERROR("invalid input\n");
164 		return -EINVAL;
165 	}
166 
167 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
168 
169 	rc = dp_panel_read_dpcd(dp_panel);
170 	bw_code = drm_dp_link_rate_to_bw_code(dp_panel->link_info.rate);
171 	if (rc || !is_link_rate_valid(bw_code) ||
172 			!is_lane_count_valid(dp_panel->link_info.num_lanes) ||
173 			(bw_code > dp_panel->max_bw_code)) {
174 		DRM_ERROR("read dpcd failed %d\n", rc);
175 		return rc;
176 	}
177 
178 	if (dp_panel->dfp_present) {
179 		rlen = drm_dp_dpcd_read(panel->aux, DP_SINK_COUNT,
180 				&count, 1);
181 		if (rlen == 1) {
182 			count = DP_GET_SINK_COUNT(count);
183 			if (!count) {
184 				DRM_ERROR("no downstream ports connected\n");
185 				panel->link->sink_count = 0;
186 				rc = -ENOTCONN;
187 				goto end;
188 			}
189 		}
190 	}
191 
192 	kfree(dp_panel->edid);
193 	dp_panel->edid = NULL;
194 
195 	dp_panel->edid = drm_get_edid(connector,
196 					      &panel->aux->ddc);
197 	if (!dp_panel->edid) {
198 		DRM_ERROR("panel edid read failed\n");
199 		/* check edid read fail is due to unplug */
200 		if (!dp_catalog_link_is_connected(panel->catalog)) {
201 			rc = -ETIMEDOUT;
202 			goto end;
203 		}
204 
205 		/* fail safe edid */
206 		mutex_lock(&connector->dev->mode_config.mutex);
207 		if (drm_add_modes_noedid(connector, 640, 480))
208 			drm_set_preferred_mode(connector, 640, 480);
209 		mutex_unlock(&connector->dev->mode_config.mutex);
210 	}
211 
212 	if (panel->aux_cfg_update_done) {
213 		DRM_DEBUG_DP("read DPCD with updated AUX config\n");
214 		rc = dp_panel_read_dpcd(dp_panel);
215 		bw_code = drm_dp_link_rate_to_bw_code(dp_panel->link_info.rate);
216 		if (rc || !is_link_rate_valid(bw_code) ||
217 			!is_lane_count_valid(dp_panel->link_info.num_lanes)
218 			|| (bw_code > dp_panel->max_bw_code)) {
219 			DRM_ERROR("read dpcd failed %d\n", rc);
220 			return rc;
221 		}
222 		panel->aux_cfg_update_done = false;
223 	}
224 end:
225 	return rc;
226 }
227 
dp_panel_get_mode_bpp(struct dp_panel *dp_panel, u32 mode_edid_bpp, u32 mode_pclk_khz)228 u32 dp_panel_get_mode_bpp(struct dp_panel *dp_panel,
229 		u32 mode_edid_bpp, u32 mode_pclk_khz)
230 {
231 	struct dp_panel_private *panel;
232 	u32 bpp = mode_edid_bpp;
233 
234 	if (!dp_panel || !mode_edid_bpp || !mode_pclk_khz) {
235 		DRM_ERROR("invalid input\n");
236 		return 0;
237 	}
238 
239 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
240 
241 	if (dp_panel->video_test)
242 		bpp = dp_link_bit_depth_to_bpp(
243 				panel->link->test_video.test_bit_depth);
244 	else
245 		bpp = dp_panel_get_supported_bpp(dp_panel, mode_edid_bpp,
246 				mode_pclk_khz);
247 
248 	return bpp;
249 }
250 
dp_panel_get_modes(struct dp_panel *dp_panel, struct drm_connector *connector, struct dp_display_mode *mode)251 int dp_panel_get_modes(struct dp_panel *dp_panel,
252 	struct drm_connector *connector, struct dp_display_mode *mode)
253 {
254 	if (!dp_panel) {
255 		DRM_ERROR("invalid input\n");
256 		return -EINVAL;
257 	}
258 
259 	if (dp_panel->edid)
260 		return dp_panel_update_modes(connector, dp_panel->edid);
261 
262 	return 0;
263 }
264 
dp_panel_get_edid_checksum(struct edid *edid)265 static u8 dp_panel_get_edid_checksum(struct edid *edid)
266 {
267 	edid += edid->extensions;
268 
269 	return edid->checksum;
270 }
271 
dp_panel_handle_sink_request(struct dp_panel *dp_panel)272 void dp_panel_handle_sink_request(struct dp_panel *dp_panel)
273 {
274 	struct dp_panel_private *panel;
275 
276 	if (!dp_panel) {
277 		DRM_ERROR("invalid input\n");
278 		return;
279 	}
280 
281 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
282 
283 	if (panel->link->sink_request & DP_TEST_LINK_EDID_READ) {
284 		u8 checksum;
285 
286 		if (dp_panel->edid)
287 			checksum = dp_panel_get_edid_checksum(dp_panel->edid);
288 		else
289 			checksum = dp_panel->connector->real_edid_checksum;
290 
291 		dp_link_send_edid_checksum(panel->link, checksum);
292 		dp_link_send_test_response(panel->link);
293 	}
294 }
295 
dp_panel_tpg_config(struct dp_panel *dp_panel, bool enable)296 void dp_panel_tpg_config(struct dp_panel *dp_panel, bool enable)
297 {
298 	struct dp_catalog *catalog;
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 	catalog = panel->catalog;
308 
309 	if (!panel->panel_on) {
310 		DRM_DEBUG_DP("DP panel not enabled, handle TPG on next on\n");
311 		return;
312 	}
313 
314 	if (!enable) {
315 		dp_catalog_panel_tpg_disable(catalog);
316 		return;
317 	}
318 
319 	DRM_DEBUG_DP("%s: calling catalog tpg_enable\n", __func__);
320 	dp_catalog_panel_tpg_enable(catalog, &panel->dp_panel.dp_mode.drm_mode);
321 }
322 
dp_panel_dump_regs(struct dp_panel *dp_panel)323 void dp_panel_dump_regs(struct dp_panel *dp_panel)
324 {
325 	struct dp_catalog *catalog;
326 	struct dp_panel_private *panel;
327 
328 	panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
329 	catalog = panel->catalog;
330 
331 	dp_catalog_dump_regs(catalog);
332 }
333 
dp_panel_timing_cfg(struct dp_panel *dp_panel)334 int dp_panel_timing_cfg(struct dp_panel *dp_panel)
335 {
336 	int rc = 0;
337 	u32 data, total_ver, total_hor;
338 	struct dp_catalog *catalog;
339 	struct dp_panel_private *panel;
340 	struct drm_display_mode *drm_mode;
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_DEBUG_DP("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_DEBUG_DP("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 	catalog->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 	catalog->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 	catalog->width_blanking = data;
379 
380 	data = drm_mode->vdisplay;
381 	data <<= 16;
382 	data |= drm_mode->hdisplay;
383 
384 	catalog->dp_active = data;
385 
386 	dp_catalog_panel_timing_cfg(catalog);
387 	panel->panel_on = true;
388 
389 	return rc;
390 }
391 
dp_panel_init_panel_info(struct dp_panel *dp_panel)392 int dp_panel_init_panel_info(struct dp_panel *dp_panel)
393 {
394 	int rc = 0;
395 	struct drm_display_mode *drm_mode;
396 
397 	drm_mode = &dp_panel->dp_mode.drm_mode;
398 
399 	/*
400 	 * print resolution info as this is a result
401 	 * of user initiated action of cable connection
402 	 */
403 	DRM_DEBUG_DP("SET NEW RESOLUTION:\n");
404 	DRM_DEBUG_DP("%dx%d@%dfps\n", drm_mode->hdisplay,
405 		drm_mode->vdisplay, drm_mode_vrefresh(drm_mode));
406 	DRM_DEBUG_DP("h_porches(back|front|width) = (%d|%d|%d)\n",
407 			drm_mode->htotal - drm_mode->hsync_end,
408 			drm_mode->hsync_start - drm_mode->hdisplay,
409 			drm_mode->hsync_end - drm_mode->hsync_start);
410 	DRM_DEBUG_DP("v_porches(back|front|width) = (%d|%d|%d)\n",
411 			drm_mode->vtotal - drm_mode->vsync_end,
412 			drm_mode->vsync_start - drm_mode->vdisplay,
413 			drm_mode->vsync_end - drm_mode->vsync_start);
414 	DRM_DEBUG_DP("pixel clock (KHz)=(%d)\n", drm_mode->clock);
415 	DRM_DEBUG_DP("bpp = %d\n", dp_panel->dp_mode.bpp);
416 
417 	dp_panel->dp_mode.bpp = max_t(u32, 18,
418 					min_t(u32, dp_panel->dp_mode.bpp, 30));
419 	DRM_DEBUG_DP("updated bpp = %d\n", dp_panel->dp_mode.bpp);
420 
421 	return rc;
422 }
423 
dp_panel_get(struct dp_panel_in *in)424 struct dp_panel *dp_panel_get(struct dp_panel_in *in)
425 {
426 	struct dp_panel_private *panel;
427 	struct dp_panel *dp_panel;
428 
429 	if (!in->dev || !in->catalog || !in->aux || !in->link) {
430 		DRM_ERROR("invalid input\n");
431 		return ERR_PTR(-EINVAL);
432 	}
433 
434 	panel = devm_kzalloc(in->dev, sizeof(*panel), GFP_KERNEL);
435 	if (!panel)
436 		return ERR_PTR(-ENOMEM);
437 
438 	panel->dev = in->dev;
439 	panel->aux = in->aux;
440 	panel->catalog = in->catalog;
441 	panel->link = in->link;
442 
443 	dp_panel = &panel->dp_panel;
444 	dp_panel->max_bw_code = DP_LINK_BW_8_1;
445 	panel->aux_cfg_update_done = false;
446 
447 	return dp_panel;
448 }
449 
dp_panel_put(struct dp_panel *dp_panel)450 void dp_panel_put(struct dp_panel *dp_panel)
451 {
452 	if (!dp_panel)
453 		return;
454 
455 	kfree(dp_panel->edid);
456 }
457