linux/drivers/gpu/drm/msm/dp/dp_panel.c
<<
>>
Prefs
   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
  12struct 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
  22static 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
 107end:
 108        return rc;
 109}
 110
 111static 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
 132static 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                return rc;
 145        }
 146
 147        rc = drm_connector_update_edid_property(connector, NULL);
 148        if (rc)
 149                DRM_ERROR("failed to update edid property %d\n", rc);
 150
 151        return rc;
 152}
 153
 154int dp_panel_read_sink_caps(struct dp_panel *dp_panel,
 155        struct drm_connector *connector)
 156{
 157        int rc = 0, bw_code;
 158        int rlen, count;
 159        struct dp_panel_private *panel;
 160
 161        if (!dp_panel || !connector) {
 162                DRM_ERROR("invalid input\n");
 163                return -EINVAL;
 164        }
 165
 166        panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
 167
 168        rc = dp_panel_read_dpcd(dp_panel);
 169        if (rc) {
 170                DRM_ERROR("read dpcd failed %d\n", rc);
 171                return rc;
 172        }
 173
 174        bw_code = drm_dp_link_rate_to_bw_code(dp_panel->link_info.rate);
 175        if (!is_link_rate_valid(bw_code) ||
 176                        !is_lane_count_valid(dp_panel->link_info.num_lanes) ||
 177                        (bw_code > dp_panel->max_bw_code)) {
 178                DRM_ERROR("Illegal link rate=%d lane=%d\n", dp_panel->link_info.rate,
 179                                dp_panel->link_info.num_lanes);
 180                return -EINVAL;
 181        }
 182
 183        if (dp_panel->dfp_present) {
 184                rlen = drm_dp_dpcd_read(panel->aux, DP_SINK_COUNT,
 185                                &count, 1);
 186                if (rlen == 1) {
 187                        count = DP_GET_SINK_COUNT(count);
 188                        if (!count) {
 189                                DRM_ERROR("no downstream ports connected\n");
 190                                panel->link->sink_count = 0;
 191                                rc = -ENOTCONN;
 192                                goto end;
 193                        }
 194                }
 195        }
 196
 197        kfree(dp_panel->edid);
 198        dp_panel->edid = NULL;
 199
 200        dp_panel->edid = drm_get_edid(connector,
 201                                              &panel->aux->ddc);
 202        if (!dp_panel->edid) {
 203                DRM_ERROR("panel edid read failed\n");
 204                /* check edid read fail is due to unplug */
 205                if (!dp_catalog_link_is_connected(panel->catalog)) {
 206                        rc = -ETIMEDOUT;
 207                        goto end;
 208                }
 209
 210                /* fail safe edid */
 211                mutex_lock(&connector->dev->mode_config.mutex);
 212                if (drm_add_modes_noedid(connector, 640, 480))
 213                        drm_set_preferred_mode(connector, 640, 480);
 214                mutex_unlock(&connector->dev->mode_config.mutex);
 215        }
 216
 217        if (panel->aux_cfg_update_done) {
 218                DRM_DEBUG_DP("read DPCD with updated AUX config\n");
 219                rc = dp_panel_read_dpcd(dp_panel);
 220                bw_code = drm_dp_link_rate_to_bw_code(dp_panel->link_info.rate);
 221                if (rc || !is_link_rate_valid(bw_code) ||
 222                        !is_lane_count_valid(dp_panel->link_info.num_lanes)
 223                        || (bw_code > dp_panel->max_bw_code)) {
 224                        DRM_ERROR("read dpcd failed %d\n", rc);
 225                        return rc;
 226                }
 227                panel->aux_cfg_update_done = false;
 228        }
 229end:
 230        return rc;
 231}
 232
 233u32 dp_panel_get_mode_bpp(struct dp_panel *dp_panel,
 234                u32 mode_edid_bpp, u32 mode_pclk_khz)
 235{
 236        struct dp_panel_private *panel;
 237        u32 bpp = mode_edid_bpp;
 238
 239        if (!dp_panel || !mode_edid_bpp || !mode_pclk_khz) {
 240                DRM_ERROR("invalid input\n");
 241                return 0;
 242        }
 243
 244        panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
 245
 246        if (dp_panel->video_test)
 247                bpp = dp_link_bit_depth_to_bpp(
 248                                panel->link->test_video.test_bit_depth);
 249        else
 250                bpp = dp_panel_get_supported_bpp(dp_panel, mode_edid_bpp,
 251                                mode_pclk_khz);
 252
 253        return bpp;
 254}
 255
 256int dp_panel_get_modes(struct dp_panel *dp_panel,
 257        struct drm_connector *connector, struct dp_display_mode *mode)
 258{
 259        if (!dp_panel) {
 260                DRM_ERROR("invalid input\n");
 261                return -EINVAL;
 262        }
 263
 264        if (dp_panel->edid)
 265                return dp_panel_update_modes(connector, dp_panel->edid);
 266
 267        return 0;
 268}
 269
 270static u8 dp_panel_get_edid_checksum(struct edid *edid)
 271{
 272        struct edid *last_block;
 273        u8 *raw_edid;
 274        bool is_edid_corrupt = false;
 275
 276        if (!edid) {
 277                DRM_ERROR("invalid edid input\n");
 278                return 0;
 279        }
 280
 281        raw_edid = (u8 *)edid;
 282        raw_edid += (edid->extensions * EDID_LENGTH);
 283        last_block = (struct edid *)raw_edid;
 284
 285        /* block type extension */
 286        drm_edid_block_valid(raw_edid, 1, false, &is_edid_corrupt);
 287        if (!is_edid_corrupt)
 288                return last_block->checksum;
 289
 290        DRM_ERROR("Invalid block, no checksum\n");
 291        return 0;
 292}
 293
 294void dp_panel_handle_sink_request(struct dp_panel *dp_panel)
 295{
 296        struct dp_panel_private *panel;
 297
 298        if (!dp_panel) {
 299                DRM_ERROR("invalid input\n");
 300                return;
 301        }
 302
 303        panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
 304
 305        if (panel->link->sink_request & DP_TEST_LINK_EDID_READ) {
 306                u8 checksum;
 307
 308                if (dp_panel->edid)
 309                        checksum = dp_panel_get_edid_checksum(dp_panel->edid);
 310                else
 311                        checksum = dp_panel->connector->real_edid_checksum;
 312
 313                dp_link_send_edid_checksum(panel->link, checksum);
 314                dp_link_send_test_response(panel->link);
 315        }
 316}
 317
 318void dp_panel_tpg_config(struct dp_panel *dp_panel, bool enable)
 319{
 320        struct dp_catalog *catalog;
 321        struct dp_panel_private *panel;
 322
 323        if (!dp_panel) {
 324                DRM_ERROR("invalid input\n");
 325                return;
 326        }
 327
 328        panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
 329        catalog = panel->catalog;
 330
 331        if (!panel->panel_on) {
 332                DRM_DEBUG_DP("DP panel not enabled, handle TPG on next on\n");
 333                return;
 334        }
 335
 336        if (!enable) {
 337                dp_catalog_panel_tpg_disable(catalog);
 338                return;
 339        }
 340
 341        DRM_DEBUG_DP("%s: calling catalog tpg_enable\n", __func__);
 342        dp_catalog_panel_tpg_enable(catalog, &panel->dp_panel.dp_mode.drm_mode);
 343}
 344
 345void dp_panel_dump_regs(struct dp_panel *dp_panel)
 346{
 347        struct dp_catalog *catalog;
 348        struct dp_panel_private *panel;
 349
 350        panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
 351        catalog = panel->catalog;
 352
 353        dp_catalog_dump_regs(catalog);
 354}
 355
 356int dp_panel_timing_cfg(struct dp_panel *dp_panel)
 357{
 358        u32 data, total_ver, total_hor;
 359        struct dp_catalog *catalog;
 360        struct dp_panel_private *panel;
 361        struct drm_display_mode *drm_mode;
 362
 363        panel = container_of(dp_panel, struct dp_panel_private, dp_panel);
 364        catalog = panel->catalog;
 365        drm_mode = &panel->dp_panel.dp_mode.drm_mode;
 366
 367        DRM_DEBUG_DP("width=%d hporch= %d %d %d\n",
 368                drm_mode->hdisplay, drm_mode->htotal - drm_mode->hsync_end,
 369                drm_mode->hsync_start - drm_mode->hdisplay,
 370                drm_mode->hsync_end - drm_mode->hsync_start);
 371
 372        DRM_DEBUG_DP("height=%d vporch= %d %d %d\n",
 373                drm_mode->vdisplay, drm_mode->vtotal - drm_mode->vsync_end,
 374                drm_mode->vsync_start - drm_mode->vdisplay,
 375                drm_mode->vsync_end - drm_mode->vsync_start);
 376
 377        total_hor = drm_mode->htotal;
 378
 379        total_ver = drm_mode->vtotal;
 380
 381        data = total_ver;
 382        data <<= 16;
 383        data |= total_hor;
 384
 385        catalog->total = data;
 386
 387        data = (drm_mode->vtotal - drm_mode->vsync_start);
 388        data <<= 16;
 389        data |= (drm_mode->htotal - drm_mode->hsync_start);
 390
 391        catalog->sync_start = data;
 392
 393        data = drm_mode->vsync_end - drm_mode->vsync_start;
 394        data <<= 16;
 395        data |= (panel->dp_panel.dp_mode.v_active_low << 31);
 396        data |= drm_mode->hsync_end - drm_mode->hsync_start;
 397        data |= (panel->dp_panel.dp_mode.h_active_low << 15);
 398
 399        catalog->width_blanking = data;
 400
 401        data = drm_mode->vdisplay;
 402        data <<= 16;
 403        data |= drm_mode->hdisplay;
 404
 405        catalog->dp_active = data;
 406
 407        dp_catalog_panel_timing_cfg(catalog);
 408        panel->panel_on = true;
 409
 410        return 0;
 411}
 412
 413int dp_panel_init_panel_info(struct dp_panel *dp_panel)
 414{
 415        struct drm_display_mode *drm_mode;
 416
 417        drm_mode = &dp_panel->dp_mode.drm_mode;
 418
 419        /*
 420         * print resolution info as this is a result
 421         * of user initiated action of cable connection
 422         */
 423        DRM_DEBUG_DP("SET NEW RESOLUTION:\n");
 424        DRM_DEBUG_DP("%dx%d@%dfps\n", drm_mode->hdisplay,
 425                drm_mode->vdisplay, drm_mode_vrefresh(drm_mode));
 426        DRM_DEBUG_DP("h_porches(back|front|width) = (%d|%d|%d)\n",
 427                        drm_mode->htotal - drm_mode->hsync_end,
 428                        drm_mode->hsync_start - drm_mode->hdisplay,
 429                        drm_mode->hsync_end - drm_mode->hsync_start);
 430        DRM_DEBUG_DP("v_porches(back|front|width) = (%d|%d|%d)\n",
 431                        drm_mode->vtotal - drm_mode->vsync_end,
 432                        drm_mode->vsync_start - drm_mode->vdisplay,
 433                        drm_mode->vsync_end - drm_mode->vsync_start);
 434        DRM_DEBUG_DP("pixel clock (KHz)=(%d)\n", drm_mode->clock);
 435        DRM_DEBUG_DP("bpp = %d\n", dp_panel->dp_mode.bpp);
 436
 437        dp_panel->dp_mode.bpp = max_t(u32, 18,
 438                                        min_t(u32, dp_panel->dp_mode.bpp, 30));
 439        DRM_DEBUG_DP("updated bpp = %d\n", dp_panel->dp_mode.bpp);
 440
 441        return 0;
 442}
 443
 444struct dp_panel *dp_panel_get(struct dp_panel_in *in)
 445{
 446        struct dp_panel_private *panel;
 447        struct dp_panel *dp_panel;
 448
 449        if (!in->dev || !in->catalog || !in->aux || !in->link) {
 450                DRM_ERROR("invalid input\n");
 451                return ERR_PTR(-EINVAL);
 452        }
 453
 454        panel = devm_kzalloc(in->dev, sizeof(*panel), GFP_KERNEL);
 455        if (!panel)
 456                return ERR_PTR(-ENOMEM);
 457
 458        panel->dev = in->dev;
 459        panel->aux = in->aux;
 460        panel->catalog = in->catalog;
 461        panel->link = in->link;
 462
 463        dp_panel = &panel->dp_panel;
 464        dp_panel->max_bw_code = DP_LINK_BW_8_1;
 465        panel->aux_cfg_update_done = false;
 466
 467        return dp_panel;
 468}
 469
 470void dp_panel_put(struct dp_panel *dp_panel)
 471{
 472        if (!dp_panel)
 473                return;
 474
 475        kfree(dp_panel->edid);
 476}
 477