linux/drivers/gpu/drm/drm_modes.c
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   1/*
   2 * Copyright © 1997-2003 by The XFree86 Project, Inc.
   3 * Copyright © 2007 Dave Airlie
   4 * Copyright © 2007-2008 Intel Corporation
   5 *   Jesse Barnes <jesse.barnes@intel.com>
   6 * Copyright 2005-2006 Luc Verhaegen
   7 * Copyright (c) 2001, Andy Ritger  aritger@nvidia.com
   8 *
   9 * Permission is hereby granted, free of charge, to any person obtaining a
  10 * copy of this software and associated documentation files (the "Software"),
  11 * to deal in the Software without restriction, including without limitation
  12 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  13 * and/or sell copies of the Software, and to permit persons to whom the
  14 * Software is furnished to do so, subject to the following conditions:
  15 *
  16 * The above copyright notice and this permission notice shall be included in
  17 * all copies or substantial portions of the Software.
  18 *
  19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  22 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
  23 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  24 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  25 * OTHER DEALINGS IN THE SOFTWARE.
  26 *
  27 * Except as contained in this notice, the name of the copyright holder(s)
  28 * and author(s) shall not be used in advertising or otherwise to promote
  29 * the sale, use or other dealings in this Software without prior written
  30 * authorization from the copyright holder(s) and author(s).
  31 */
  32
  33#include <linux/list.h>
  34#include <linux/list_sort.h>
  35#include <linux/export.h>
  36#include "drmP.h"
  37#include "drm.h"
  38#include "drm_crtc.h"
  39
  40/**
  41 * drm_mode_debug_printmodeline - debug print a mode
  42 * @dev: DRM device
  43 * @mode: mode to print
  44 *
  45 * LOCKING:
  46 * None.
  47 *
  48 * Describe @mode using DRM_DEBUG.
  49 */
  50void drm_mode_debug_printmodeline(struct drm_display_mode *mode)
  51{
  52        DRM_DEBUG_KMS("Modeline %d:\"%s\" %d %d %d %d %d %d %d %d %d %d "
  53                        "0x%x 0x%x\n",
  54                mode->base.id, mode->name, mode->vrefresh, mode->clock,
  55                mode->hdisplay, mode->hsync_start,
  56                mode->hsync_end, mode->htotal,
  57                mode->vdisplay, mode->vsync_start,
  58                mode->vsync_end, mode->vtotal, mode->type, mode->flags);
  59}
  60EXPORT_SYMBOL(drm_mode_debug_printmodeline);
  61
  62/**
  63 * drm_cvt_mode -create a modeline based on CVT algorithm
  64 * @dev: DRM device
  65 * @hdisplay: hdisplay size
  66 * @vdisplay: vdisplay size
  67 * @vrefresh  : vrefresh rate
  68 * @reduced : Whether the GTF calculation is simplified
  69 * @interlaced:Whether the interlace is supported
  70 *
  71 * LOCKING:
  72 * none.
  73 *
  74 * return the modeline based on CVT algorithm
  75 *
  76 * This function is called to generate the modeline based on CVT algorithm
  77 * according to the hdisplay, vdisplay, vrefresh.
  78 * It is based from the VESA(TM) Coordinated Video Timing Generator by
  79 * Graham Loveridge April 9, 2003 available at
  80 * http://www.elo.utfsm.cl/~elo212/docs/CVTd6r1.xls 
  81 *
  82 * And it is copied from xf86CVTmode in xserver/hw/xfree86/modes/xf86cvt.c.
  83 * What I have done is to translate it by using integer calculation.
  84 */
  85#define HV_FACTOR                       1000
  86struct drm_display_mode *drm_cvt_mode(struct drm_device *dev, int hdisplay,
  87                                      int vdisplay, int vrefresh,
  88                                      bool reduced, bool interlaced, bool margins)
  89{
  90        /* 1) top/bottom margin size (% of height) - default: 1.8, */
  91#define CVT_MARGIN_PERCENTAGE           18
  92        /* 2) character cell horizontal granularity (pixels) - default 8 */
  93#define CVT_H_GRANULARITY               8
  94        /* 3) Minimum vertical porch (lines) - default 3 */
  95#define CVT_MIN_V_PORCH                 3
  96        /* 4) Minimum number of vertical back porch lines - default 6 */
  97#define CVT_MIN_V_BPORCH                6
  98        /* Pixel Clock step (kHz) */
  99#define CVT_CLOCK_STEP                  250
 100        struct drm_display_mode *drm_mode;
 101        unsigned int vfieldrate, hperiod;
 102        int hdisplay_rnd, hmargin, vdisplay_rnd, vmargin, vsync;
 103        int interlace;
 104
 105        /* allocate the drm_display_mode structure. If failure, we will
 106         * return directly
 107         */
 108        drm_mode = drm_mode_create(dev);
 109        if (!drm_mode)
 110                return NULL;
 111
 112        /* the CVT default refresh rate is 60Hz */
 113        if (!vrefresh)
 114                vrefresh = 60;
 115
 116        /* the required field fresh rate */
 117        if (interlaced)
 118                vfieldrate = vrefresh * 2;
 119        else
 120                vfieldrate = vrefresh;
 121
 122        /* horizontal pixels */
 123        hdisplay_rnd = hdisplay - (hdisplay % CVT_H_GRANULARITY);
 124
 125        /* determine the left&right borders */
 126        hmargin = 0;
 127        if (margins) {
 128                hmargin = hdisplay_rnd * CVT_MARGIN_PERCENTAGE / 1000;
 129                hmargin -= hmargin % CVT_H_GRANULARITY;
 130        }
 131        /* find the total active pixels */
 132        drm_mode->hdisplay = hdisplay_rnd + 2 * hmargin;
 133
 134        /* find the number of lines per field */
 135        if (interlaced)
 136                vdisplay_rnd = vdisplay / 2;
 137        else
 138                vdisplay_rnd = vdisplay;
 139
 140        /* find the top & bottom borders */
 141        vmargin = 0;
 142        if (margins)
 143                vmargin = vdisplay_rnd * CVT_MARGIN_PERCENTAGE / 1000;
 144
 145        drm_mode->vdisplay = vdisplay + 2 * vmargin;
 146
 147        /* Interlaced */
 148        if (interlaced)
 149                interlace = 1;
 150        else
 151                interlace = 0;
 152
 153        /* Determine VSync Width from aspect ratio */
 154        if (!(vdisplay % 3) && ((vdisplay * 4 / 3) == hdisplay))
 155                vsync = 4;
 156        else if (!(vdisplay % 9) && ((vdisplay * 16 / 9) == hdisplay))
 157                vsync = 5;
 158        else if (!(vdisplay % 10) && ((vdisplay * 16 / 10) == hdisplay))
 159                vsync = 6;
 160        else if (!(vdisplay % 4) && ((vdisplay * 5 / 4) == hdisplay))
 161                vsync = 7;
 162        else if (!(vdisplay % 9) && ((vdisplay * 15 / 9) == hdisplay))
 163                vsync = 7;
 164        else /* custom */
 165                vsync = 10;
 166
 167        if (!reduced) {
 168                /* simplify the GTF calculation */
 169                /* 4) Minimum time of vertical sync + back porch interval (µs)
 170                 * default 550.0
 171                 */
 172                int tmp1, tmp2;
 173#define CVT_MIN_VSYNC_BP        550
 174                /* 3) Nominal HSync width (% of line period) - default 8 */
 175#define CVT_HSYNC_PERCENTAGE    8
 176                unsigned int hblank_percentage;
 177                int vsyncandback_porch, vback_porch, hblank;
 178
 179                /* estimated the horizontal period */
 180                tmp1 = HV_FACTOR * 1000000  -
 181                                CVT_MIN_VSYNC_BP * HV_FACTOR * vfieldrate;
 182                tmp2 = (vdisplay_rnd + 2 * vmargin + CVT_MIN_V_PORCH) * 2 +
 183                                interlace;
 184                hperiod = tmp1 * 2 / (tmp2 * vfieldrate);
 185
 186                tmp1 = CVT_MIN_VSYNC_BP * HV_FACTOR / hperiod + 1;
 187                /* 9. Find number of lines in sync + backporch */
 188                if (tmp1 < (vsync + CVT_MIN_V_PORCH))
 189                        vsyncandback_porch = vsync + CVT_MIN_V_PORCH;
 190                else
 191                        vsyncandback_porch = tmp1;
 192                /* 10. Find number of lines in back porch */
 193                vback_porch = vsyncandback_porch - vsync;
 194                drm_mode->vtotal = vdisplay_rnd + 2 * vmargin +
 195                                vsyncandback_porch + CVT_MIN_V_PORCH;
 196                /* 5) Definition of Horizontal blanking time limitation */
 197                /* Gradient (%/kHz) - default 600 */
 198#define CVT_M_FACTOR    600
 199                /* Offset (%) - default 40 */
 200#define CVT_C_FACTOR    40
 201                /* Blanking time scaling factor - default 128 */
 202#define CVT_K_FACTOR    128
 203                /* Scaling factor weighting - default 20 */
 204#define CVT_J_FACTOR    20
 205#define CVT_M_PRIME     (CVT_M_FACTOR * CVT_K_FACTOR / 256)
 206#define CVT_C_PRIME     ((CVT_C_FACTOR - CVT_J_FACTOR) * CVT_K_FACTOR / 256 + \
 207                         CVT_J_FACTOR)
 208                /* 12. Find ideal blanking duty cycle from formula */
 209                hblank_percentage = CVT_C_PRIME * HV_FACTOR - CVT_M_PRIME *
 210                                        hperiod / 1000;
 211                /* 13. Blanking time */
 212                if (hblank_percentage < 20 * HV_FACTOR)
 213                        hblank_percentage = 20 * HV_FACTOR;
 214                hblank = drm_mode->hdisplay * hblank_percentage /
 215                         (100 * HV_FACTOR - hblank_percentage);
 216                hblank -= hblank % (2 * CVT_H_GRANULARITY);
 217                /* 14. find the total pixes per line */
 218                drm_mode->htotal = drm_mode->hdisplay + hblank;
 219                drm_mode->hsync_end = drm_mode->hdisplay + hblank / 2;
 220                drm_mode->hsync_start = drm_mode->hsync_end -
 221                        (drm_mode->htotal * CVT_HSYNC_PERCENTAGE) / 100;
 222                drm_mode->hsync_start += CVT_H_GRANULARITY -
 223                        drm_mode->hsync_start % CVT_H_GRANULARITY;
 224                /* fill the Vsync values */
 225                drm_mode->vsync_start = drm_mode->vdisplay + CVT_MIN_V_PORCH;
 226                drm_mode->vsync_end = drm_mode->vsync_start + vsync;
 227        } else {
 228                /* Reduced blanking */
 229                /* Minimum vertical blanking interval time (µs)- default 460 */
 230#define CVT_RB_MIN_VBLANK       460
 231                /* Fixed number of clocks for horizontal sync */
 232#define CVT_RB_H_SYNC           32
 233                /* Fixed number of clocks for horizontal blanking */
 234#define CVT_RB_H_BLANK          160
 235                /* Fixed number of lines for vertical front porch - default 3*/
 236#define CVT_RB_VFPORCH          3
 237                int vbilines;
 238                int tmp1, tmp2;
 239                /* 8. Estimate Horizontal period. */
 240                tmp1 = HV_FACTOR * 1000000 -
 241                        CVT_RB_MIN_VBLANK * HV_FACTOR * vfieldrate;
 242                tmp2 = vdisplay_rnd + 2 * vmargin;
 243                hperiod = tmp1 / (tmp2 * vfieldrate);
 244                /* 9. Find number of lines in vertical blanking */
 245                vbilines = CVT_RB_MIN_VBLANK * HV_FACTOR / hperiod + 1;
 246                /* 10. Check if vertical blanking is sufficient */
 247                if (vbilines < (CVT_RB_VFPORCH + vsync + CVT_MIN_V_BPORCH))
 248                        vbilines = CVT_RB_VFPORCH + vsync + CVT_MIN_V_BPORCH;
 249                /* 11. Find total number of lines in vertical field */
 250                drm_mode->vtotal = vdisplay_rnd + 2 * vmargin + vbilines;
 251                /* 12. Find total number of pixels in a line */
 252                drm_mode->htotal = drm_mode->hdisplay + CVT_RB_H_BLANK;
 253                /* Fill in HSync values */
 254                drm_mode->hsync_end = drm_mode->hdisplay + CVT_RB_H_BLANK / 2;
 255                drm_mode->hsync_start = drm_mode->hsync_end - CVT_RB_H_SYNC;
 256                /* Fill in VSync values */
 257                drm_mode->vsync_start = drm_mode->vdisplay + CVT_RB_VFPORCH;
 258                drm_mode->vsync_end = drm_mode->vsync_start + vsync;
 259        }
 260        /* 15/13. Find pixel clock frequency (kHz for xf86) */
 261        drm_mode->clock = drm_mode->htotal * HV_FACTOR * 1000 / hperiod;
 262        drm_mode->clock -= drm_mode->clock % CVT_CLOCK_STEP;
 263        /* 18/16. Find actual vertical frame frequency */
 264        /* ignore - just set the mode flag for interlaced */
 265        if (interlaced) {
 266                drm_mode->vtotal *= 2;
 267                drm_mode->flags |= DRM_MODE_FLAG_INTERLACE;
 268        }
 269        /* Fill the mode line name */
 270        drm_mode_set_name(drm_mode);
 271        if (reduced)
 272                drm_mode->flags |= (DRM_MODE_FLAG_PHSYNC |
 273                                        DRM_MODE_FLAG_NVSYNC);
 274        else
 275                drm_mode->flags |= (DRM_MODE_FLAG_PVSYNC |
 276                                        DRM_MODE_FLAG_NHSYNC);
 277
 278        return drm_mode;
 279}
 280EXPORT_SYMBOL(drm_cvt_mode);
 281
 282/**
 283 * drm_gtf_mode_complex - create the modeline based on full GTF algorithm
 284 *
 285 * @dev         :drm device
 286 * @hdisplay    :hdisplay size
 287 * @vdisplay    :vdisplay size
 288 * @vrefresh    :vrefresh rate.
 289 * @interlaced  :whether the interlace is supported
 290 * @margins     :desired margin size
 291 * @GTF_[MCKJ]  :extended GTF formula parameters
 292 *
 293 * LOCKING.
 294 * none.
 295 *
 296 * return the modeline based on full GTF algorithm.
 297 *
 298 * GTF feature blocks specify C and J in multiples of 0.5, so we pass them
 299 * in here multiplied by two.  For a C of 40, pass in 80.
 300 */
 301struct drm_display_mode *
 302drm_gtf_mode_complex(struct drm_device *dev, int hdisplay, int vdisplay,
 303                     int vrefresh, bool interlaced, int margins,
 304                     int GTF_M, int GTF_2C, int GTF_K, int GTF_2J)
 305{       /* 1) top/bottom margin size (% of height) - default: 1.8, */
 306#define GTF_MARGIN_PERCENTAGE           18
 307        /* 2) character cell horizontal granularity (pixels) - default 8 */
 308#define GTF_CELL_GRAN                   8
 309        /* 3) Minimum vertical porch (lines) - default 3 */
 310#define GTF_MIN_V_PORCH                 1
 311        /* width of vsync in lines */
 312#define V_SYNC_RQD                      3
 313        /* width of hsync as % of total line */
 314#define H_SYNC_PERCENT                  8
 315        /* min time of vsync + back porch (microsec) */
 316#define MIN_VSYNC_PLUS_BP               550
 317        /* C' and M' are part of the Blanking Duty Cycle computation */
 318#define GTF_C_PRIME     ((((GTF_2C - GTF_2J) * GTF_K / 256) + GTF_2J) / 2)
 319#define GTF_M_PRIME     (GTF_K * GTF_M / 256)
 320        struct drm_display_mode *drm_mode;
 321        unsigned int hdisplay_rnd, vdisplay_rnd, vfieldrate_rqd;
 322        int top_margin, bottom_margin;
 323        int interlace;
 324        unsigned int hfreq_est;
 325        int vsync_plus_bp, vback_porch;
 326        unsigned int vtotal_lines, vfieldrate_est, hperiod;
 327        unsigned int vfield_rate, vframe_rate;
 328        int left_margin, right_margin;
 329        unsigned int total_active_pixels, ideal_duty_cycle;
 330        unsigned int hblank, total_pixels, pixel_freq;
 331        int hsync, hfront_porch, vodd_front_porch_lines;
 332        unsigned int tmp1, tmp2;
 333
 334        drm_mode = drm_mode_create(dev);
 335        if (!drm_mode)
 336                return NULL;
 337
 338        /* 1. In order to give correct results, the number of horizontal
 339         * pixels requested is first processed to ensure that it is divisible
 340         * by the character size, by rounding it to the nearest character
 341         * cell boundary:
 342         */
 343        hdisplay_rnd = (hdisplay + GTF_CELL_GRAN / 2) / GTF_CELL_GRAN;
 344        hdisplay_rnd = hdisplay_rnd * GTF_CELL_GRAN;
 345
 346        /* 2. If interlace is requested, the number of vertical lines assumed
 347         * by the calculation must be halved, as the computation calculates
 348         * the number of vertical lines per field.
 349         */
 350        if (interlaced)
 351                vdisplay_rnd = vdisplay / 2;
 352        else
 353                vdisplay_rnd = vdisplay;
 354
 355        /* 3. Find the frame rate required: */
 356        if (interlaced)
 357                vfieldrate_rqd = vrefresh * 2;
 358        else
 359                vfieldrate_rqd = vrefresh;
 360
 361        /* 4. Find number of lines in Top margin: */
 362        top_margin = 0;
 363        if (margins)
 364                top_margin = (vdisplay_rnd * GTF_MARGIN_PERCENTAGE + 500) /
 365                                1000;
 366        /* 5. Find number of lines in bottom margin: */
 367        bottom_margin = top_margin;
 368
 369        /* 6. If interlace is required, then set variable interlace: */
 370        if (interlaced)
 371                interlace = 1;
 372        else
 373                interlace = 0;
 374
 375        /* 7. Estimate the Horizontal frequency */
 376        {
 377                tmp1 = (1000000  - MIN_VSYNC_PLUS_BP * vfieldrate_rqd) / 500;
 378                tmp2 = (vdisplay_rnd + 2 * top_margin + GTF_MIN_V_PORCH) *
 379                                2 + interlace;
 380                hfreq_est = (tmp2 * 1000 * vfieldrate_rqd) / tmp1;
 381        }
 382
 383        /* 8. Find the number of lines in V sync + back porch */
 384        /* [V SYNC+BP] = RINT(([MIN VSYNC+BP] * hfreq_est / 1000000)) */
 385        vsync_plus_bp = MIN_VSYNC_PLUS_BP * hfreq_est / 1000;
 386        vsync_plus_bp = (vsync_plus_bp + 500) / 1000;
 387        /*  9. Find the number of lines in V back porch alone: */
 388        vback_porch = vsync_plus_bp - V_SYNC_RQD;
 389        /*  10. Find the total number of lines in Vertical field period: */
 390        vtotal_lines = vdisplay_rnd + top_margin + bottom_margin +
 391                        vsync_plus_bp + GTF_MIN_V_PORCH;
 392        /*  11. Estimate the Vertical field frequency: */
 393        vfieldrate_est = hfreq_est / vtotal_lines;
 394        /*  12. Find the actual horizontal period: */
 395        hperiod = 1000000 / (vfieldrate_rqd * vtotal_lines);
 396
 397        /*  13. Find the actual Vertical field frequency: */
 398        vfield_rate = hfreq_est / vtotal_lines;
 399        /*  14. Find the Vertical frame frequency: */
 400        if (interlaced)
 401                vframe_rate = vfield_rate / 2;
 402        else
 403                vframe_rate = vfield_rate;
 404        /*  15. Find number of pixels in left margin: */
 405        if (margins)
 406                left_margin = (hdisplay_rnd * GTF_MARGIN_PERCENTAGE + 500) /
 407                                1000;
 408        else
 409                left_margin = 0;
 410
 411        /* 16.Find number of pixels in right margin: */
 412        right_margin = left_margin;
 413        /* 17.Find total number of active pixels in image and left and right */
 414        total_active_pixels = hdisplay_rnd + left_margin + right_margin;
 415        /* 18.Find the ideal blanking duty cycle from blanking duty cycle */
 416        ideal_duty_cycle = GTF_C_PRIME * 1000 -
 417                                (GTF_M_PRIME * 1000000 / hfreq_est);
 418        /* 19.Find the number of pixels in the blanking time to the nearest
 419         * double character cell: */
 420        hblank = total_active_pixels * ideal_duty_cycle /
 421                        (100000 - ideal_duty_cycle);
 422        hblank = (hblank + GTF_CELL_GRAN) / (2 * GTF_CELL_GRAN);
 423        hblank = hblank * 2 * GTF_CELL_GRAN;
 424        /* 20.Find total number of pixels: */
 425        total_pixels = total_active_pixels + hblank;
 426        /* 21.Find pixel clock frequency: */
 427        pixel_freq = total_pixels * hfreq_est / 1000;
 428        /* Stage 1 computations are now complete; I should really pass
 429         * the results to another function and do the Stage 2 computations,
 430         * but I only need a few more values so I'll just append the
 431         * computations here for now */
 432        /* 17. Find the number of pixels in the horizontal sync period: */
 433        hsync = H_SYNC_PERCENT * total_pixels / 100;
 434        hsync = (hsync + GTF_CELL_GRAN / 2) / GTF_CELL_GRAN;
 435        hsync = hsync * GTF_CELL_GRAN;
 436        /* 18. Find the number of pixels in horizontal front porch period */
 437        hfront_porch = hblank / 2 - hsync;
 438        /*  36. Find the number of lines in the odd front porch period: */
 439        vodd_front_porch_lines = GTF_MIN_V_PORCH ;
 440
 441        /* finally, pack the results in the mode struct */
 442        drm_mode->hdisplay = hdisplay_rnd;
 443        drm_mode->hsync_start = hdisplay_rnd + hfront_porch;
 444        drm_mode->hsync_end = drm_mode->hsync_start + hsync;
 445        drm_mode->htotal = total_pixels;
 446        drm_mode->vdisplay = vdisplay_rnd;
 447        drm_mode->vsync_start = vdisplay_rnd + vodd_front_porch_lines;
 448        drm_mode->vsync_end = drm_mode->vsync_start + V_SYNC_RQD;
 449        drm_mode->vtotal = vtotal_lines;
 450
 451        drm_mode->clock = pixel_freq;
 452
 453        if (interlaced) {
 454                drm_mode->vtotal *= 2;
 455                drm_mode->flags |= DRM_MODE_FLAG_INTERLACE;
 456        }
 457
 458        drm_mode_set_name(drm_mode);
 459        if (GTF_M == 600 && GTF_2C == 80 && GTF_K == 128 && GTF_2J == 40)
 460                drm_mode->flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_PVSYNC;
 461        else
 462                drm_mode->flags = DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_NVSYNC;
 463
 464        return drm_mode;
 465}
 466EXPORT_SYMBOL(drm_gtf_mode_complex);
 467
 468/**
 469 * drm_gtf_mode - create the modeline based on GTF algorithm
 470 *
 471 * @dev         :drm device
 472 * @hdisplay    :hdisplay size
 473 * @vdisplay    :vdisplay size
 474 * @vrefresh    :vrefresh rate.
 475 * @interlaced  :whether the interlace is supported
 476 * @margins     :whether the margin is supported
 477 *
 478 * LOCKING.
 479 * none.
 480 *
 481 * return the modeline based on GTF algorithm
 482 *
 483 * This function is to create the modeline based on the GTF algorithm.
 484 * Generalized Timing Formula is derived from:
 485 *      GTF Spreadsheet by Andy Morrish (1/5/97)
 486 *      available at http://www.vesa.org
 487 *
 488 * And it is copied from the file of xserver/hw/xfree86/modes/xf86gtf.c.
 489 * What I have done is to translate it by using integer calculation.
 490 * I also refer to the function of fb_get_mode in the file of
 491 * drivers/video/fbmon.c
 492 *
 493 * Standard GTF parameters:
 494 * M = 600
 495 * C = 40
 496 * K = 128
 497 * J = 20
 498 */
 499struct drm_display_mode *
 500drm_gtf_mode(struct drm_device *dev, int hdisplay, int vdisplay, int vrefresh,
 501             bool lace, int margins)
 502{
 503        return drm_gtf_mode_complex(dev, hdisplay, vdisplay, vrefresh, lace,
 504                                    margins, 600, 40 * 2, 128, 20 * 2);
 505}
 506EXPORT_SYMBOL(drm_gtf_mode);
 507
 508/**
 509 * drm_mode_set_name - set the name on a mode
 510 * @mode: name will be set in this mode
 511 *
 512 * LOCKING:
 513 * None.
 514 *
 515 * Set the name of @mode to a standard format.
 516 */
 517void drm_mode_set_name(struct drm_display_mode *mode)
 518{
 519        bool interlaced = !!(mode->flags & DRM_MODE_FLAG_INTERLACE);
 520
 521        snprintf(mode->name, DRM_DISPLAY_MODE_LEN, "%dx%d%s",
 522                 mode->hdisplay, mode->vdisplay,
 523                 interlaced ? "i" : "");
 524}
 525EXPORT_SYMBOL(drm_mode_set_name);
 526
 527/**
 528 * drm_mode_list_concat - move modes from one list to another
 529 * @head: source list
 530 * @new: dst list
 531 *
 532 * LOCKING:
 533 * Caller must ensure both lists are locked.
 534 *
 535 * Move all the modes from @head to @new.
 536 */
 537void drm_mode_list_concat(struct list_head *head, struct list_head *new)
 538{
 539
 540        struct list_head *entry, *tmp;
 541
 542        list_for_each_safe(entry, tmp, head) {
 543                list_move_tail(entry, new);
 544        }
 545}
 546EXPORT_SYMBOL(drm_mode_list_concat);
 547
 548/**
 549 * drm_mode_width - get the width of a mode
 550 * @mode: mode
 551 *
 552 * LOCKING:
 553 * None.
 554 *
 555 * Return @mode's width (hdisplay) value.
 556 *
 557 * FIXME: is this needed?
 558 *
 559 * RETURNS:
 560 * @mode->hdisplay
 561 */
 562int drm_mode_width(struct drm_display_mode *mode)
 563{
 564        return mode->hdisplay;
 565
 566}
 567EXPORT_SYMBOL(drm_mode_width);
 568
 569/**
 570 * drm_mode_height - get the height of a mode
 571 * @mode: mode
 572 *
 573 * LOCKING:
 574 * None.
 575 *
 576 * Return @mode's height (vdisplay) value.
 577 *
 578 * FIXME: is this needed?
 579 *
 580 * RETURNS:
 581 * @mode->vdisplay
 582 */
 583int drm_mode_height(struct drm_display_mode *mode)
 584{
 585        return mode->vdisplay;
 586}
 587EXPORT_SYMBOL(drm_mode_height);
 588
 589/** drm_mode_hsync - get the hsync of a mode
 590 * @mode: mode
 591 *
 592 * LOCKING:
 593 * None.
 594 *
 595 * Return @modes's hsync rate in kHz, rounded to the nearest int.
 596 */
 597int drm_mode_hsync(const struct drm_display_mode *mode)
 598{
 599        unsigned int calc_val;
 600
 601        if (mode->hsync)
 602                return mode->hsync;
 603
 604        if (mode->htotal < 0)
 605                return 0;
 606
 607        calc_val = (mode->clock * 1000) / mode->htotal; /* hsync in Hz */
 608        calc_val += 500;                                /* round to 1000Hz */
 609        calc_val /= 1000;                               /* truncate to kHz */
 610
 611        return calc_val;
 612}
 613EXPORT_SYMBOL(drm_mode_hsync);
 614
 615/**
 616 * drm_mode_vrefresh - get the vrefresh of a mode
 617 * @mode: mode
 618 *
 619 * LOCKING:
 620 * None.
 621 *
 622 * Return @mode's vrefresh rate in Hz or calculate it if necessary.
 623 *
 624 * FIXME: why is this needed?  shouldn't vrefresh be set already?
 625 *
 626 * RETURNS:
 627 * Vertical refresh rate. It will be the result of actual value plus 0.5.
 628 * If it is 70.288, it will return 70Hz.
 629 * If it is 59.6, it will return 60Hz.
 630 */
 631int drm_mode_vrefresh(const struct drm_display_mode *mode)
 632{
 633        int refresh = 0;
 634        unsigned int calc_val;
 635
 636        if (mode->vrefresh > 0)
 637                refresh = mode->vrefresh;
 638        else if (mode->htotal > 0 && mode->vtotal > 0) {
 639                int vtotal;
 640                vtotal = mode->vtotal;
 641                /* work out vrefresh the value will be x1000 */
 642                calc_val = (mode->clock * 1000);
 643                calc_val /= mode->htotal;
 644                refresh = (calc_val + vtotal / 2) / vtotal;
 645
 646                if (mode->flags & DRM_MODE_FLAG_INTERLACE)
 647                        refresh *= 2;
 648                if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
 649                        refresh /= 2;
 650                if (mode->vscan > 1)
 651                        refresh /= mode->vscan;
 652        }
 653        return refresh;
 654}
 655EXPORT_SYMBOL(drm_mode_vrefresh);
 656
 657/**
 658 * drm_mode_set_crtcinfo - set CRTC modesetting parameters
 659 * @p: mode
 660 * @adjust_flags: unused? (FIXME)
 661 *
 662 * LOCKING:
 663 * None.
 664 *
 665 * Setup the CRTC modesetting parameters for @p, adjusting if necessary.
 666 */
 667void drm_mode_set_crtcinfo(struct drm_display_mode *p, int adjust_flags)
 668{
 669        if ((p == NULL) || ((p->type & DRM_MODE_TYPE_CRTC_C) == DRM_MODE_TYPE_BUILTIN))
 670                return;
 671
 672        p->crtc_hdisplay = p->hdisplay;
 673        p->crtc_hsync_start = p->hsync_start;
 674        p->crtc_hsync_end = p->hsync_end;
 675        p->crtc_htotal = p->htotal;
 676        p->crtc_hskew = p->hskew;
 677        p->crtc_vdisplay = p->vdisplay;
 678        p->crtc_vsync_start = p->vsync_start;
 679        p->crtc_vsync_end = p->vsync_end;
 680        p->crtc_vtotal = p->vtotal;
 681
 682        if (p->flags & DRM_MODE_FLAG_INTERLACE) {
 683                if (adjust_flags & CRTC_INTERLACE_HALVE_V) {
 684                        p->crtc_vdisplay /= 2;
 685                        p->crtc_vsync_start /= 2;
 686                        p->crtc_vsync_end /= 2;
 687                        p->crtc_vtotal /= 2;
 688                }
 689
 690                p->crtc_vtotal |= 1;
 691        }
 692
 693        if (p->flags & DRM_MODE_FLAG_DBLSCAN) {
 694                p->crtc_vdisplay *= 2;
 695                p->crtc_vsync_start *= 2;
 696                p->crtc_vsync_end *= 2;
 697                p->crtc_vtotal *= 2;
 698        }
 699
 700        if (p->vscan > 1) {
 701                p->crtc_vdisplay *= p->vscan;
 702                p->crtc_vsync_start *= p->vscan;
 703                p->crtc_vsync_end *= p->vscan;
 704                p->crtc_vtotal *= p->vscan;
 705        }
 706
 707        p->crtc_vblank_start = min(p->crtc_vsync_start, p->crtc_vdisplay);
 708        p->crtc_vblank_end = max(p->crtc_vsync_end, p->crtc_vtotal);
 709        p->crtc_hblank_start = min(p->crtc_hsync_start, p->crtc_hdisplay);
 710        p->crtc_hblank_end = max(p->crtc_hsync_end, p->crtc_htotal);
 711
 712        p->crtc_hadjusted = false;
 713        p->crtc_vadjusted = false;
 714}
 715EXPORT_SYMBOL(drm_mode_set_crtcinfo);
 716
 717
 718/**
 719 * drm_mode_duplicate - allocate and duplicate an existing mode
 720 * @m: mode to duplicate
 721 *
 722 * LOCKING:
 723 * None.
 724 *
 725 * Just allocate a new mode, copy the existing mode into it, and return
 726 * a pointer to it.  Used to create new instances of established modes.
 727 */
 728struct drm_display_mode *drm_mode_duplicate(struct drm_device *dev,
 729                                            const struct drm_display_mode *mode)
 730{
 731        struct drm_display_mode *nmode;
 732        int new_id;
 733
 734        nmode = drm_mode_create(dev);
 735        if (!nmode)
 736                return NULL;
 737
 738        new_id = nmode->base.id;
 739        *nmode = *mode;
 740        nmode->base.id = new_id;
 741        INIT_LIST_HEAD(&nmode->head);
 742        return nmode;
 743}
 744EXPORT_SYMBOL(drm_mode_duplicate);
 745
 746/**
 747 * drm_mode_equal - test modes for equality
 748 * @mode1: first mode
 749 * @mode2: second mode
 750 *
 751 * LOCKING:
 752 * None.
 753 *
 754 * Check to see if @mode1 and @mode2 are equivalent.
 755 *
 756 * RETURNS:
 757 * True if the modes are equal, false otherwise.
 758 */
 759bool drm_mode_equal(struct drm_display_mode *mode1, struct drm_display_mode *mode2)
 760{
 761        /* do clock check convert to PICOS so fb modes get matched
 762         * the same */
 763        if (mode1->clock && mode2->clock) {
 764                if (KHZ2PICOS(mode1->clock) != KHZ2PICOS(mode2->clock))
 765                        return false;
 766        } else if (mode1->clock != mode2->clock)
 767                return false;
 768
 769        if (mode1->hdisplay == mode2->hdisplay &&
 770            mode1->hsync_start == mode2->hsync_start &&
 771            mode1->hsync_end == mode2->hsync_end &&
 772            mode1->htotal == mode2->htotal &&
 773            mode1->hskew == mode2->hskew &&
 774            mode1->vdisplay == mode2->vdisplay &&
 775            mode1->vsync_start == mode2->vsync_start &&
 776            mode1->vsync_end == mode2->vsync_end &&
 777            mode1->vtotal == mode2->vtotal &&
 778            mode1->vscan == mode2->vscan &&
 779            mode1->flags == mode2->flags)
 780                return true;
 781
 782        return false;
 783}
 784EXPORT_SYMBOL(drm_mode_equal);
 785
 786/**
 787 * drm_mode_validate_size - make sure modes adhere to size constraints
 788 * @dev: DRM device
 789 * @mode_list: list of modes to check
 790 * @maxX: maximum width
 791 * @maxY: maximum height
 792 * @maxPitch: max pitch
 793 *
 794 * LOCKING:
 795 * Caller must hold a lock protecting @mode_list.
 796 *
 797 * The DRM device (@dev) has size and pitch limits.  Here we validate the
 798 * modes we probed for @dev against those limits and set their status as
 799 * necessary.
 800 */
 801void drm_mode_validate_size(struct drm_device *dev,
 802                            struct list_head *mode_list,
 803                            int maxX, int maxY, int maxPitch)
 804{
 805        struct drm_display_mode *mode;
 806
 807        list_for_each_entry(mode, mode_list, head) {
 808                if (maxPitch > 0 && mode->hdisplay > maxPitch)
 809                        mode->status = MODE_BAD_WIDTH;
 810
 811                if (maxX > 0 && mode->hdisplay > maxX)
 812                        mode->status = MODE_VIRTUAL_X;
 813
 814                if (maxY > 0 && mode->vdisplay > maxY)
 815                        mode->status = MODE_VIRTUAL_Y;
 816        }
 817}
 818EXPORT_SYMBOL(drm_mode_validate_size);
 819
 820/**
 821 * drm_mode_validate_clocks - validate modes against clock limits
 822 * @dev: DRM device
 823 * @mode_list: list of modes to check
 824 * @min: minimum clock rate array
 825 * @max: maximum clock rate array
 826 * @n_ranges: number of clock ranges (size of arrays)
 827 *
 828 * LOCKING:
 829 * Caller must hold a lock protecting @mode_list.
 830 *
 831 * Some code may need to check a mode list against the clock limits of the
 832 * device in question.  This function walks the mode list, testing to make
 833 * sure each mode falls within a given range (defined by @min and @max
 834 * arrays) and sets @mode->status as needed.
 835 */
 836void drm_mode_validate_clocks(struct drm_device *dev,
 837                              struct list_head *mode_list,
 838                              int *min, int *max, int n_ranges)
 839{
 840        struct drm_display_mode *mode;
 841        int i;
 842
 843        list_for_each_entry(mode, mode_list, head) {
 844                bool good = false;
 845                for (i = 0; i < n_ranges; i++) {
 846                        if (mode->clock >= min[i] && mode->clock <= max[i]) {
 847                                good = true;
 848                                break;
 849                        }
 850                }
 851                if (!good)
 852                        mode->status = MODE_CLOCK_RANGE;
 853        }
 854}
 855EXPORT_SYMBOL(drm_mode_validate_clocks);
 856
 857/**
 858 * drm_mode_prune_invalid - remove invalid modes from mode list
 859 * @dev: DRM device
 860 * @mode_list: list of modes to check
 861 * @verbose: be verbose about it
 862 *
 863 * LOCKING:
 864 * Caller must hold a lock protecting @mode_list.
 865 *
 866 * Once mode list generation is complete, a caller can use this routine to
 867 * remove invalid modes from a mode list.  If any of the modes have a
 868 * status other than %MODE_OK, they are removed from @mode_list and freed.
 869 */
 870void drm_mode_prune_invalid(struct drm_device *dev,
 871                            struct list_head *mode_list, bool verbose)
 872{
 873        struct drm_display_mode *mode, *t;
 874
 875        list_for_each_entry_safe(mode, t, mode_list, head) {
 876                if (mode->status != MODE_OK) {
 877                        list_del(&mode->head);
 878                        if (verbose) {
 879                                drm_mode_debug_printmodeline(mode);
 880                                DRM_DEBUG_KMS("Not using %s mode %d\n",
 881                                        mode->name, mode->status);
 882                        }
 883                        drm_mode_destroy(dev, mode);
 884                }
 885        }
 886}
 887EXPORT_SYMBOL(drm_mode_prune_invalid);
 888
 889/**
 890 * drm_mode_compare - compare modes for favorability
 891 * @priv: unused
 892 * @lh_a: list_head for first mode
 893 * @lh_b: list_head for second mode
 894 *
 895 * LOCKING:
 896 * None.
 897 *
 898 * Compare two modes, given by @lh_a and @lh_b, returning a value indicating
 899 * which is better.
 900 *
 901 * RETURNS:
 902 * Negative if @lh_a is better than @lh_b, zero if they're equivalent, or
 903 * positive if @lh_b is better than @lh_a.
 904 */
 905static int drm_mode_compare(void *priv, struct list_head *lh_a, struct list_head *lh_b)
 906{
 907        struct drm_display_mode *a = list_entry(lh_a, struct drm_display_mode, head);
 908        struct drm_display_mode *b = list_entry(lh_b, struct drm_display_mode, head);
 909        int diff;
 910
 911        diff = ((b->type & DRM_MODE_TYPE_PREFERRED) != 0) -
 912                ((a->type & DRM_MODE_TYPE_PREFERRED) != 0);
 913        if (diff)
 914                return diff;
 915        diff = b->hdisplay * b->vdisplay - a->hdisplay * a->vdisplay;
 916        if (diff)
 917                return diff;
 918        diff = b->clock - a->clock;
 919        return diff;
 920}
 921
 922/**
 923 * drm_mode_sort - sort mode list
 924 * @mode_list: list to sort
 925 *
 926 * LOCKING:
 927 * Caller must hold a lock protecting @mode_list.
 928 *
 929 * Sort @mode_list by favorability, putting good modes first.
 930 */
 931void drm_mode_sort(struct list_head *mode_list)
 932{
 933        list_sort(NULL, mode_list, drm_mode_compare);
 934}
 935EXPORT_SYMBOL(drm_mode_sort);
 936
 937/**
 938 * drm_mode_connector_list_update - update the mode list for the connector
 939 * @connector: the connector to update
 940 *
 941 * LOCKING:
 942 * Caller must hold a lock protecting @mode_list.
 943 *
 944 * This moves the modes from the @connector probed_modes list
 945 * to the actual mode list. It compares the probed mode against the current
 946 * list and only adds different modes. All modes unverified after this point
 947 * will be removed by the prune invalid modes.
 948 */
 949void drm_mode_connector_list_update(struct drm_connector *connector)
 950{
 951        struct drm_display_mode *mode;
 952        struct drm_display_mode *pmode, *pt;
 953        int found_it;
 954
 955        list_for_each_entry_safe(pmode, pt, &connector->probed_modes,
 956                                 head) {
 957                found_it = 0;
 958                /* go through current modes checking for the new probed mode */
 959                list_for_each_entry(mode, &connector->modes, head) {
 960                        if (drm_mode_equal(pmode, mode)) {
 961                                found_it = 1;
 962                                /* if equal delete the probed mode */
 963                                mode->status = pmode->status;
 964                                /* Merge type bits together */
 965                                mode->type |= pmode->type;
 966                                list_del(&pmode->head);
 967                                drm_mode_destroy(connector->dev, pmode);
 968                                break;
 969                        }
 970                }
 971
 972                if (!found_it) {
 973                        list_move_tail(&pmode->head, &connector->modes);
 974                }
 975        }
 976}
 977EXPORT_SYMBOL(drm_mode_connector_list_update);
 978
 979/**
 980 * drm_mode_parse_command_line_for_connector - parse command line for connector
 981 * @mode_option - per connector mode option
 982 * @connector - connector to parse line for
 983 *
 984 * This parses the connector specific then generic command lines for
 985 * modes and options to configure the connector.
 986 *
 987 * This uses the same parameters as the fb modedb.c, except for extra
 988 *      <xres>x<yres>[M][R][-<bpp>][@<refresh>][i][m][eDd]
 989 *
 990 * enable/enable Digital/disable bit at the end
 991 */
 992bool drm_mode_parse_command_line_for_connector(const char *mode_option,
 993                                               struct drm_connector *connector,
 994                                               struct drm_cmdline_mode *mode)
 995{
 996        const char *name;
 997        unsigned int namelen;
 998        bool res_specified = false, bpp_specified = false, refresh_specified = false;
 999        unsigned int xres = 0, yres = 0, bpp = 32, refresh = 0;
1000        bool yres_specified = false, cvt = false, rb = false;
1001        bool interlace = false, margins = false, was_digit = false;
1002        int i;
1003        enum drm_connector_force force = DRM_FORCE_UNSPECIFIED;
1004
1005#ifdef CONFIG_FB
1006        if (!mode_option)
1007                mode_option = fb_mode_option;
1008#endif
1009
1010        if (!mode_option) {
1011                mode->specified = false;
1012                return false;
1013        }
1014
1015        name = mode_option;
1016        namelen = strlen(name);
1017        for (i = namelen-1; i >= 0; i--) {
1018                switch (name[i]) {
1019                case '@':
1020                        if (!refresh_specified && !bpp_specified &&
1021                            !yres_specified && !cvt && !rb && was_digit) {
1022                                refresh = simple_strtol(&name[i+1], NULL, 10);
1023                                refresh_specified = true;
1024                                was_digit = false;
1025                        } else
1026                                goto done;
1027                        break;
1028                case '-':
1029                        if (!bpp_specified && !yres_specified && !cvt &&
1030                            !rb && was_digit) {
1031                                bpp = simple_strtol(&name[i+1], NULL, 10);
1032                                bpp_specified = true;
1033                                was_digit = false;
1034                        } else
1035                                goto done;
1036                        break;
1037                case 'x':
1038                        if (!yres_specified && was_digit) {
1039                                yres = simple_strtol(&name[i+1], NULL, 10);
1040                                yres_specified = true;
1041                                was_digit = false;
1042                        } else
1043                                goto done;
1044                case '0' ... '9':
1045                        was_digit = true;
1046                        break;
1047                case 'M':
1048                        if (yres_specified || cvt || was_digit)
1049                                goto done;
1050                        cvt = true;
1051                        break;
1052                case 'R':
1053                        if (yres_specified || cvt || rb || was_digit)
1054                                goto done;
1055                        rb = true;
1056                        break;
1057                case 'm':
1058                        if (cvt || yres_specified || was_digit)
1059                                goto done;
1060                        margins = true;
1061                        break;
1062                case 'i':
1063                        if (cvt || yres_specified || was_digit)
1064                                goto done;
1065                        interlace = true;
1066                        break;
1067                case 'e':
1068                        if (yres_specified || bpp_specified || refresh_specified ||
1069                            was_digit || (force != DRM_FORCE_UNSPECIFIED))
1070                                goto done;
1071
1072                        force = DRM_FORCE_ON;
1073                        break;
1074                case 'D':
1075                        if (yres_specified || bpp_specified || refresh_specified ||
1076                            was_digit || (force != DRM_FORCE_UNSPECIFIED))
1077                                goto done;
1078
1079                        if ((connector->connector_type != DRM_MODE_CONNECTOR_DVII) &&
1080                            (connector->connector_type != DRM_MODE_CONNECTOR_HDMIB))
1081                                force = DRM_FORCE_ON;
1082                        else
1083                                force = DRM_FORCE_ON_DIGITAL;
1084                        break;
1085                case 'd':
1086                        if (yres_specified || bpp_specified || refresh_specified ||
1087                            was_digit || (force != DRM_FORCE_UNSPECIFIED))
1088                                goto done;
1089
1090                        force = DRM_FORCE_OFF;
1091                        break;
1092                default:
1093                        goto done;
1094                }
1095        }
1096
1097        if (i < 0 && yres_specified) {
1098                char *ch;
1099                xres = simple_strtol(name, &ch, 10);
1100                if ((ch != NULL) && (*ch == 'x'))
1101                        res_specified = true;
1102                else
1103                        i = ch - name;
1104        } else if (!yres_specified && was_digit) {
1105                /* catch mode that begins with digits but has no 'x' */
1106                i = 0;
1107        }
1108done:
1109        if (i >= 0) {
1110                printk(KERN_WARNING
1111                        "parse error at position %i in video mode '%s'\n",
1112                        i, name);
1113                mode->specified = false;
1114                return false;
1115        }
1116
1117        if (res_specified) {
1118                mode->specified = true;
1119                mode->xres = xres;
1120                mode->yres = yres;
1121        }
1122
1123        if (refresh_specified) {
1124                mode->refresh_specified = true;
1125                mode->refresh = refresh;
1126        }
1127
1128        if (bpp_specified) {
1129                mode->bpp_specified = true;
1130                mode->bpp = bpp;
1131        }
1132        mode->rb = rb;
1133        mode->cvt = cvt;
1134        mode->interlace = interlace;
1135        mode->margins = margins;
1136        mode->force = force;
1137
1138        return true;
1139}
1140EXPORT_SYMBOL(drm_mode_parse_command_line_for_connector);
1141
1142struct drm_display_mode *
1143drm_mode_create_from_cmdline_mode(struct drm_device *dev,
1144                                  struct drm_cmdline_mode *cmd)
1145{
1146        struct drm_display_mode *mode;
1147
1148        if (cmd->cvt)
1149                mode = drm_cvt_mode(dev,
1150                                    cmd->xres, cmd->yres,
1151                                    cmd->refresh_specified ? cmd->refresh : 60,
1152                                    cmd->rb, cmd->interlace,
1153                                    cmd->margins);
1154        else
1155                mode = drm_gtf_mode(dev,
1156                                    cmd->xres, cmd->yres,
1157                                    cmd->refresh_specified ? cmd->refresh : 60,
1158                                    cmd->interlace,
1159                                    cmd->margins);
1160        if (!mode)
1161                return NULL;
1162
1163        drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);
1164        return mode;
1165}
1166EXPORT_SYMBOL(drm_mode_create_from_cmdline_mode);
1167