1 // SPDX-License-Identifier: MIT 2 /* 3 * Copyright © 2021 Intel Corporation 4 */ 5 6 #include "i915_reg.h" 7 #include "intel_de.h" 8 #include "intel_display_types.h" 9 #include "intel_panel.h" 10 #include "intel_pch_refclk.h" 11 #include "intel_sbi.h" 12 13 static void lpt_fdi_reset_mphy(struct drm_i915_private *dev_priv) 14 { 15 intel_de_rmw(dev_priv, SOUTH_CHICKEN2, 0, FDI_MPHY_IOSFSB_RESET_CTL); 16 17 if (wait_for_us(intel_de_read(dev_priv, SOUTH_CHICKEN2) & 18 FDI_MPHY_IOSFSB_RESET_STATUS, 100)) 19 drm_err(&dev_priv->drm, "FDI mPHY reset assert timeout\n"); 20 21 intel_de_rmw(dev_priv, SOUTH_CHICKEN2, FDI_MPHY_IOSFSB_RESET_CTL, 0); 22 23 if (wait_for_us((intel_de_read(dev_priv, SOUTH_CHICKEN2) & 24 FDI_MPHY_IOSFSB_RESET_STATUS) == 0, 100)) 25 drm_err(&dev_priv->drm, "FDI mPHY reset de-assert timeout\n"); 26 } 27 28 /* WaMPhyProgramming:hsw */ 29 static void lpt_fdi_program_mphy(struct drm_i915_private *dev_priv) 30 { 31 u32 tmp; 32 33 lpt_fdi_reset_mphy(dev_priv); 34 35 tmp = intel_sbi_read(dev_priv, 0x8008, SBI_MPHY); 36 tmp &= ~(0xFF << 24); 37 tmp |= (0x12 << 24); 38 intel_sbi_write(dev_priv, 0x8008, tmp, SBI_MPHY); 39 40 tmp = intel_sbi_read(dev_priv, 0x2008, SBI_MPHY); 41 tmp |= (1 << 11); 42 intel_sbi_write(dev_priv, 0x2008, tmp, SBI_MPHY); 43 44 tmp = intel_sbi_read(dev_priv, 0x2108, SBI_MPHY); 45 tmp |= (1 << 11); 46 intel_sbi_write(dev_priv, 0x2108, tmp, SBI_MPHY); 47 48 tmp = intel_sbi_read(dev_priv, 0x206C, SBI_MPHY); 49 tmp |= (1 << 24) | (1 << 21) | (1 << 18); 50 intel_sbi_write(dev_priv, 0x206C, tmp, SBI_MPHY); 51 52 tmp = intel_sbi_read(dev_priv, 0x216C, SBI_MPHY); 53 tmp |= (1 << 24) | (1 << 21) | (1 << 18); 54 intel_sbi_write(dev_priv, 0x216C, tmp, SBI_MPHY); 55 56 tmp = intel_sbi_read(dev_priv, 0x2080, SBI_MPHY); 57 tmp &= ~(7 << 13); 58 tmp |= (5 << 13); 59 intel_sbi_write(dev_priv, 0x2080, tmp, SBI_MPHY); 60 61 tmp = intel_sbi_read(dev_priv, 0x2180, SBI_MPHY); 62 tmp &= ~(7 << 13); 63 tmp |= (5 << 13); 64 intel_sbi_write(dev_priv, 0x2180, tmp, SBI_MPHY); 65 66 tmp = intel_sbi_read(dev_priv, 0x208C, SBI_MPHY); 67 tmp &= ~0xFF; 68 tmp |= 0x1C; 69 intel_sbi_write(dev_priv, 0x208C, tmp, SBI_MPHY); 70 71 tmp = intel_sbi_read(dev_priv, 0x218C, SBI_MPHY); 72 tmp &= ~0xFF; 73 tmp |= 0x1C; 74 intel_sbi_write(dev_priv, 0x218C, tmp, SBI_MPHY); 75 76 tmp = intel_sbi_read(dev_priv, 0x2098, SBI_MPHY); 77 tmp &= ~(0xFF << 16); 78 tmp |= (0x1C << 16); 79 intel_sbi_write(dev_priv, 0x2098, tmp, SBI_MPHY); 80 81 tmp = intel_sbi_read(dev_priv, 0x2198, SBI_MPHY); 82 tmp &= ~(0xFF << 16); 83 tmp |= (0x1C << 16); 84 intel_sbi_write(dev_priv, 0x2198, tmp, SBI_MPHY); 85 86 tmp = intel_sbi_read(dev_priv, 0x20C4, SBI_MPHY); 87 tmp |= (1 << 27); 88 intel_sbi_write(dev_priv, 0x20C4, tmp, SBI_MPHY); 89 90 tmp = intel_sbi_read(dev_priv, 0x21C4, SBI_MPHY); 91 tmp |= (1 << 27); 92 intel_sbi_write(dev_priv, 0x21C4, tmp, SBI_MPHY); 93 94 tmp = intel_sbi_read(dev_priv, 0x20EC, SBI_MPHY); 95 tmp &= ~(0xF << 28); 96 tmp |= (4 << 28); 97 intel_sbi_write(dev_priv, 0x20EC, tmp, SBI_MPHY); 98 99 tmp = intel_sbi_read(dev_priv, 0x21EC, SBI_MPHY); 100 tmp &= ~(0xF << 28); 101 tmp |= (4 << 28); 102 intel_sbi_write(dev_priv, 0x21EC, tmp, SBI_MPHY); 103 } 104 105 void lpt_disable_iclkip(struct drm_i915_private *dev_priv) 106 { 107 u32 temp; 108 109 intel_de_write(dev_priv, PIXCLK_GATE, PIXCLK_GATE_GATE); 110 111 mutex_lock(&dev_priv->sb_lock); 112 113 temp = intel_sbi_read(dev_priv, SBI_SSCCTL6, SBI_ICLK); 114 temp |= SBI_SSCCTL_DISABLE; 115 intel_sbi_write(dev_priv, SBI_SSCCTL6, temp, SBI_ICLK); 116 117 mutex_unlock(&dev_priv->sb_lock); 118 } 119 120 struct iclkip_params { 121 u32 iclk_virtual_root_freq; 122 u32 iclk_pi_range; 123 u32 divsel, phaseinc, auxdiv, phasedir, desired_divisor; 124 }; 125 126 static void iclkip_params_init(struct iclkip_params *p) 127 { 128 memset(p, 0, sizeof(*p)); 129 130 p->iclk_virtual_root_freq = 172800 * 1000; 131 p->iclk_pi_range = 64; 132 } 133 134 static int lpt_iclkip_freq(struct iclkip_params *p) 135 { 136 return DIV_ROUND_CLOSEST(p->iclk_virtual_root_freq, 137 p->desired_divisor << p->auxdiv); 138 } 139 140 static void lpt_compute_iclkip(struct iclkip_params *p, int clock) 141 { 142 iclkip_params_init(p); 143 144 /* The iCLK virtual clock root frequency is in MHz, 145 * but the adjusted_mode->crtc_clock in KHz. To get the 146 * divisors, it is necessary to divide one by another, so we 147 * convert the virtual clock precision to KHz here for higher 148 * precision. 149 */ 150 for (p->auxdiv = 0; p->auxdiv < 2; p->auxdiv++) { 151 p->desired_divisor = DIV_ROUND_CLOSEST(p->iclk_virtual_root_freq, 152 clock << p->auxdiv); 153 p->divsel = (p->desired_divisor / p->iclk_pi_range) - 2; 154 p->phaseinc = p->desired_divisor % p->iclk_pi_range; 155 156 /* 157 * Near 20MHz is a corner case which is 158 * out of range for the 7-bit divisor 159 */ 160 if (p->divsel <= 0x7f) 161 break; 162 } 163 } 164 165 int lpt_iclkip(const struct intel_crtc_state *crtc_state) 166 { 167 struct iclkip_params p; 168 169 lpt_compute_iclkip(&p, crtc_state->hw.adjusted_mode.crtc_clock); 170 171 return lpt_iclkip_freq(&p); 172 } 173 174 /* Program iCLKIP clock to the desired frequency */ 175 void lpt_program_iclkip(const struct intel_crtc_state *crtc_state) 176 { 177 struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc); 178 struct drm_i915_private *dev_priv = to_i915(crtc->base.dev); 179 int clock = crtc_state->hw.adjusted_mode.crtc_clock; 180 struct iclkip_params p; 181 u32 temp; 182 183 lpt_disable_iclkip(dev_priv); 184 185 lpt_compute_iclkip(&p, clock); 186 drm_WARN_ON(&dev_priv->drm, lpt_iclkip_freq(&p) != clock); 187 188 /* This should not happen with any sane values */ 189 drm_WARN_ON(&dev_priv->drm, SBI_SSCDIVINTPHASE_DIVSEL(p.divsel) & 190 ~SBI_SSCDIVINTPHASE_DIVSEL_MASK); 191 drm_WARN_ON(&dev_priv->drm, SBI_SSCDIVINTPHASE_DIR(p.phasedir) & 192 ~SBI_SSCDIVINTPHASE_INCVAL_MASK); 193 194 drm_dbg_kms(&dev_priv->drm, 195 "iCLKIP clock: found settings for %dKHz refresh rate: auxdiv=%x, divsel=%x, phasedir=%x, phaseinc=%x\n", 196 clock, p.auxdiv, p.divsel, p.phasedir, p.phaseinc); 197 198 mutex_lock(&dev_priv->sb_lock); 199 200 /* Program SSCDIVINTPHASE6 */ 201 temp = intel_sbi_read(dev_priv, SBI_SSCDIVINTPHASE6, SBI_ICLK); 202 temp &= ~SBI_SSCDIVINTPHASE_DIVSEL_MASK; 203 temp |= SBI_SSCDIVINTPHASE_DIVSEL(p.divsel); 204 temp &= ~SBI_SSCDIVINTPHASE_INCVAL_MASK; 205 temp |= SBI_SSCDIVINTPHASE_INCVAL(p.phaseinc); 206 temp |= SBI_SSCDIVINTPHASE_DIR(p.phasedir); 207 temp |= SBI_SSCDIVINTPHASE_PROPAGATE; 208 intel_sbi_write(dev_priv, SBI_SSCDIVINTPHASE6, temp, SBI_ICLK); 209 210 /* Program SSCAUXDIV */ 211 temp = intel_sbi_read(dev_priv, SBI_SSCAUXDIV6, SBI_ICLK); 212 temp &= ~SBI_SSCAUXDIV_FINALDIV2SEL(1); 213 temp |= SBI_SSCAUXDIV_FINALDIV2SEL(p.auxdiv); 214 intel_sbi_write(dev_priv, SBI_SSCAUXDIV6, temp, SBI_ICLK); 215 216 /* Enable modulator and associated divider */ 217 temp = intel_sbi_read(dev_priv, SBI_SSCCTL6, SBI_ICLK); 218 temp &= ~SBI_SSCCTL_DISABLE; 219 intel_sbi_write(dev_priv, SBI_SSCCTL6, temp, SBI_ICLK); 220 221 mutex_unlock(&dev_priv->sb_lock); 222 223 /* Wait for initialization time */ 224 udelay(24); 225 226 intel_de_write(dev_priv, PIXCLK_GATE, PIXCLK_GATE_UNGATE); 227 } 228 229 int lpt_get_iclkip(struct drm_i915_private *dev_priv) 230 { 231 struct iclkip_params p; 232 u32 temp; 233 234 if ((intel_de_read(dev_priv, PIXCLK_GATE) & PIXCLK_GATE_UNGATE) == 0) 235 return 0; 236 237 iclkip_params_init(&p); 238 239 mutex_lock(&dev_priv->sb_lock); 240 241 temp = intel_sbi_read(dev_priv, SBI_SSCCTL6, SBI_ICLK); 242 if (temp & SBI_SSCCTL_DISABLE) { 243 mutex_unlock(&dev_priv->sb_lock); 244 return 0; 245 } 246 247 temp = intel_sbi_read(dev_priv, SBI_SSCDIVINTPHASE6, SBI_ICLK); 248 p.divsel = (temp & SBI_SSCDIVINTPHASE_DIVSEL_MASK) >> 249 SBI_SSCDIVINTPHASE_DIVSEL_SHIFT; 250 p.phaseinc = (temp & SBI_SSCDIVINTPHASE_INCVAL_MASK) >> 251 SBI_SSCDIVINTPHASE_INCVAL_SHIFT; 252 253 temp = intel_sbi_read(dev_priv, SBI_SSCAUXDIV6, SBI_ICLK); 254 p.auxdiv = (temp & SBI_SSCAUXDIV_FINALDIV2SEL_MASK) >> 255 SBI_SSCAUXDIV_FINALDIV2SEL_SHIFT; 256 257 mutex_unlock(&dev_priv->sb_lock); 258 259 p.desired_divisor = (p.divsel + 2) * p.iclk_pi_range + p.phaseinc; 260 261 return lpt_iclkip_freq(&p); 262 } 263 264 /* Implements 3 different sequences from BSpec chapter "Display iCLK 265 * Programming" based on the parameters passed: 266 * - Sequence to enable CLKOUT_DP 267 * - Sequence to enable CLKOUT_DP without spread 268 * - Sequence to enable CLKOUT_DP for FDI usage and configure PCH FDI I/O 269 */ 270 static void lpt_enable_clkout_dp(struct drm_i915_private *dev_priv, 271 bool with_spread, bool with_fdi) 272 { 273 u32 reg, tmp; 274 275 if (drm_WARN(&dev_priv->drm, with_fdi && !with_spread, 276 "FDI requires downspread\n")) 277 with_spread = true; 278 if (drm_WARN(&dev_priv->drm, HAS_PCH_LPT_LP(dev_priv) && 279 with_fdi, "LP PCH doesn't have FDI\n")) 280 with_fdi = false; 281 282 mutex_lock(&dev_priv->sb_lock); 283 284 tmp = intel_sbi_read(dev_priv, SBI_SSCCTL, SBI_ICLK); 285 tmp &= ~SBI_SSCCTL_DISABLE; 286 tmp |= SBI_SSCCTL_PATHALT; 287 intel_sbi_write(dev_priv, SBI_SSCCTL, tmp, SBI_ICLK); 288 289 udelay(24); 290 291 if (with_spread) { 292 tmp = intel_sbi_read(dev_priv, SBI_SSCCTL, SBI_ICLK); 293 tmp &= ~SBI_SSCCTL_PATHALT; 294 intel_sbi_write(dev_priv, SBI_SSCCTL, tmp, SBI_ICLK); 295 296 if (with_fdi) 297 lpt_fdi_program_mphy(dev_priv); 298 } 299 300 reg = HAS_PCH_LPT_LP(dev_priv) ? SBI_GEN0 : SBI_DBUFF0; 301 tmp = intel_sbi_read(dev_priv, reg, SBI_ICLK); 302 tmp |= SBI_GEN0_CFG_BUFFENABLE_DISABLE; 303 intel_sbi_write(dev_priv, reg, tmp, SBI_ICLK); 304 305 mutex_unlock(&dev_priv->sb_lock); 306 } 307 308 /* Sequence to disable CLKOUT_DP */ 309 void lpt_disable_clkout_dp(struct drm_i915_private *dev_priv) 310 { 311 u32 reg, tmp; 312 313 mutex_lock(&dev_priv->sb_lock); 314 315 reg = HAS_PCH_LPT_LP(dev_priv) ? SBI_GEN0 : SBI_DBUFF0; 316 tmp = intel_sbi_read(dev_priv, reg, SBI_ICLK); 317 tmp &= ~SBI_GEN0_CFG_BUFFENABLE_DISABLE; 318 intel_sbi_write(dev_priv, reg, tmp, SBI_ICLK); 319 320 tmp = intel_sbi_read(dev_priv, SBI_SSCCTL, SBI_ICLK); 321 if (!(tmp & SBI_SSCCTL_DISABLE)) { 322 if (!(tmp & SBI_SSCCTL_PATHALT)) { 323 tmp |= SBI_SSCCTL_PATHALT; 324 intel_sbi_write(dev_priv, SBI_SSCCTL, tmp, SBI_ICLK); 325 udelay(32); 326 } 327 tmp |= SBI_SSCCTL_DISABLE; 328 intel_sbi_write(dev_priv, SBI_SSCCTL, tmp, SBI_ICLK); 329 } 330 331 mutex_unlock(&dev_priv->sb_lock); 332 } 333 334 #define BEND_IDX(steps) ((50 + (steps)) / 5) 335 336 static const u16 sscdivintphase[] = { 337 [BEND_IDX( 50)] = 0x3B23, 338 [BEND_IDX( 45)] = 0x3B23, 339 [BEND_IDX( 40)] = 0x3C23, 340 [BEND_IDX( 35)] = 0x3C23, 341 [BEND_IDX( 30)] = 0x3D23, 342 [BEND_IDX( 25)] = 0x3D23, 343 [BEND_IDX( 20)] = 0x3E23, 344 [BEND_IDX( 15)] = 0x3E23, 345 [BEND_IDX( 10)] = 0x3F23, 346 [BEND_IDX( 5)] = 0x3F23, 347 [BEND_IDX( 0)] = 0x0025, 348 [BEND_IDX( -5)] = 0x0025, 349 [BEND_IDX(-10)] = 0x0125, 350 [BEND_IDX(-15)] = 0x0125, 351 [BEND_IDX(-20)] = 0x0225, 352 [BEND_IDX(-25)] = 0x0225, 353 [BEND_IDX(-30)] = 0x0325, 354 [BEND_IDX(-35)] = 0x0325, 355 [BEND_IDX(-40)] = 0x0425, 356 [BEND_IDX(-45)] = 0x0425, 357 [BEND_IDX(-50)] = 0x0525, 358 }; 359 360 /* 361 * Bend CLKOUT_DP 362 * steps -50 to 50 inclusive, in steps of 5 363 * < 0 slow down the clock, > 0 speed up the clock, 0 == no bend (135MHz) 364 * change in clock period = -(steps / 10) * 5.787 ps 365 */ 366 static void lpt_bend_clkout_dp(struct drm_i915_private *dev_priv, int steps) 367 { 368 u32 tmp; 369 int idx = BEND_IDX(steps); 370 371 if (drm_WARN_ON(&dev_priv->drm, steps % 5 != 0)) 372 return; 373 374 if (drm_WARN_ON(&dev_priv->drm, idx >= ARRAY_SIZE(sscdivintphase))) 375 return; 376 377 mutex_lock(&dev_priv->sb_lock); 378 379 if (steps % 10 != 0) 380 tmp = 0xAAAAAAAB; 381 else 382 tmp = 0x00000000; 383 intel_sbi_write(dev_priv, SBI_SSCDITHPHASE, tmp, SBI_ICLK); 384 385 tmp = intel_sbi_read(dev_priv, SBI_SSCDIVINTPHASE, SBI_ICLK); 386 tmp &= 0xffff0000; 387 tmp |= sscdivintphase[idx]; 388 intel_sbi_write(dev_priv, SBI_SSCDIVINTPHASE, tmp, SBI_ICLK); 389 390 mutex_unlock(&dev_priv->sb_lock); 391 } 392 393 #undef BEND_IDX 394 395 static bool spll_uses_pch_ssc(struct drm_i915_private *dev_priv) 396 { 397 u32 fuse_strap = intel_de_read(dev_priv, FUSE_STRAP); 398 u32 ctl = intel_de_read(dev_priv, SPLL_CTL); 399 400 if ((ctl & SPLL_PLL_ENABLE) == 0) 401 return false; 402 403 if ((ctl & SPLL_REF_MASK) == SPLL_REF_MUXED_SSC && 404 (fuse_strap & HSW_CPU_SSC_ENABLE) == 0) 405 return true; 406 407 if (IS_BROADWELL(dev_priv) && 408 (ctl & SPLL_REF_MASK) == SPLL_REF_PCH_SSC_BDW) 409 return true; 410 411 return false; 412 } 413 414 static bool wrpll_uses_pch_ssc(struct drm_i915_private *dev_priv, 415 enum intel_dpll_id id) 416 { 417 u32 fuse_strap = intel_de_read(dev_priv, FUSE_STRAP); 418 u32 ctl = intel_de_read(dev_priv, WRPLL_CTL(id)); 419 420 if ((ctl & WRPLL_PLL_ENABLE) == 0) 421 return false; 422 423 if ((ctl & WRPLL_REF_MASK) == WRPLL_REF_PCH_SSC) 424 return true; 425 426 if ((IS_BROADWELL(dev_priv) || IS_HASWELL_ULT(dev_priv)) && 427 (ctl & WRPLL_REF_MASK) == WRPLL_REF_MUXED_SSC_BDW && 428 (fuse_strap & HSW_CPU_SSC_ENABLE) == 0) 429 return true; 430 431 return false; 432 } 433 434 static void lpt_init_pch_refclk(struct drm_i915_private *dev_priv) 435 { 436 struct intel_encoder *encoder; 437 bool has_fdi = false; 438 439 for_each_intel_encoder(&dev_priv->drm, encoder) { 440 switch (encoder->type) { 441 case INTEL_OUTPUT_ANALOG: 442 has_fdi = true; 443 break; 444 default: 445 break; 446 } 447 } 448 449 /* 450 * The BIOS may have decided to use the PCH SSC 451 * reference so we must not disable it until the 452 * relevant PLLs have stopped relying on it. We'll 453 * just leave the PCH SSC reference enabled in case 454 * any active PLL is using it. It will get disabled 455 * after runtime suspend if we don't have FDI. 456 * 457 * TODO: Move the whole reference clock handling 458 * to the modeset sequence proper so that we can 459 * actually enable/disable/reconfigure these things 460 * safely. To do that we need to introduce a real 461 * clock hierarchy. That would also allow us to do 462 * clock bending finally. 463 */ 464 dev_priv->display.dpll.pch_ssc_use = 0; 465 466 if (spll_uses_pch_ssc(dev_priv)) { 467 drm_dbg_kms(&dev_priv->drm, "SPLL using PCH SSC\n"); 468 dev_priv->display.dpll.pch_ssc_use |= BIT(DPLL_ID_SPLL); 469 } 470 471 if (wrpll_uses_pch_ssc(dev_priv, DPLL_ID_WRPLL1)) { 472 drm_dbg_kms(&dev_priv->drm, "WRPLL1 using PCH SSC\n"); 473 dev_priv->display.dpll.pch_ssc_use |= BIT(DPLL_ID_WRPLL1); 474 } 475 476 if (wrpll_uses_pch_ssc(dev_priv, DPLL_ID_WRPLL2)) { 477 drm_dbg_kms(&dev_priv->drm, "WRPLL2 using PCH SSC\n"); 478 dev_priv->display.dpll.pch_ssc_use |= BIT(DPLL_ID_WRPLL2); 479 } 480 481 if (dev_priv->display.dpll.pch_ssc_use) 482 return; 483 484 if (has_fdi) { 485 lpt_bend_clkout_dp(dev_priv, 0); 486 lpt_enable_clkout_dp(dev_priv, true, true); 487 } else { 488 lpt_disable_clkout_dp(dev_priv); 489 } 490 } 491 492 static void ilk_init_pch_refclk(struct drm_i915_private *dev_priv) 493 { 494 struct intel_encoder *encoder; 495 int i; 496 u32 val, final; 497 bool has_lvds = false; 498 bool has_cpu_edp = false; 499 bool has_panel = false; 500 bool has_ck505 = false; 501 bool can_ssc = false; 502 bool using_ssc_source = false; 503 504 /* We need to take the global config into account */ 505 for_each_intel_encoder(&dev_priv->drm, encoder) { 506 switch (encoder->type) { 507 case INTEL_OUTPUT_LVDS: 508 has_panel = true; 509 has_lvds = true; 510 break; 511 case INTEL_OUTPUT_EDP: 512 has_panel = true; 513 if (encoder->port == PORT_A) 514 has_cpu_edp = true; 515 break; 516 default: 517 break; 518 } 519 } 520 521 if (HAS_PCH_IBX(dev_priv)) { 522 has_ck505 = dev_priv->display.vbt.display_clock_mode; 523 can_ssc = has_ck505; 524 } else { 525 has_ck505 = false; 526 can_ssc = true; 527 } 528 529 /* Check if any DPLLs are using the SSC source */ 530 for (i = 0; i < dev_priv->display.dpll.num_shared_dpll; i++) { 531 u32 temp = intel_de_read(dev_priv, PCH_DPLL(i)); 532 533 if (!(temp & DPLL_VCO_ENABLE)) 534 continue; 535 536 if ((temp & PLL_REF_INPUT_MASK) == 537 PLLB_REF_INPUT_SPREADSPECTRUMIN) { 538 using_ssc_source = true; 539 break; 540 } 541 } 542 543 drm_dbg_kms(&dev_priv->drm, 544 "has_panel %d has_lvds %d has_ck505 %d using_ssc_source %d\n", 545 has_panel, has_lvds, has_ck505, using_ssc_source); 546 547 /* Ironlake: try to setup display ref clock before DPLL 548 * enabling. This is only under driver's control after 549 * PCH B stepping, previous chipset stepping should be 550 * ignoring this setting. 551 */ 552 val = intel_de_read(dev_priv, PCH_DREF_CONTROL); 553 554 /* As we must carefully and slowly disable/enable each source in turn, 555 * compute the final state we want first and check if we need to 556 * make any changes at all. 557 */ 558 final = val; 559 final &= ~DREF_NONSPREAD_SOURCE_MASK; 560 if (has_ck505) 561 final |= DREF_NONSPREAD_CK505_ENABLE; 562 else 563 final |= DREF_NONSPREAD_SOURCE_ENABLE; 564 565 final &= ~DREF_SSC_SOURCE_MASK; 566 final &= ~DREF_CPU_SOURCE_OUTPUT_MASK; 567 final &= ~DREF_SSC1_ENABLE; 568 569 if (has_panel) { 570 final |= DREF_SSC_SOURCE_ENABLE; 571 572 if (intel_panel_use_ssc(dev_priv) && can_ssc) 573 final |= DREF_SSC1_ENABLE; 574 575 if (has_cpu_edp) { 576 if (intel_panel_use_ssc(dev_priv) && can_ssc) 577 final |= DREF_CPU_SOURCE_OUTPUT_DOWNSPREAD; 578 else 579 final |= DREF_CPU_SOURCE_OUTPUT_NONSPREAD; 580 } else { 581 final |= DREF_CPU_SOURCE_OUTPUT_DISABLE; 582 } 583 } else if (using_ssc_source) { 584 final |= DREF_SSC_SOURCE_ENABLE; 585 final |= DREF_SSC1_ENABLE; 586 } 587 588 if (final == val) 589 return; 590 591 /* Always enable nonspread source */ 592 val &= ~DREF_NONSPREAD_SOURCE_MASK; 593 594 if (has_ck505) 595 val |= DREF_NONSPREAD_CK505_ENABLE; 596 else 597 val |= DREF_NONSPREAD_SOURCE_ENABLE; 598 599 if (has_panel) { 600 val &= ~DREF_SSC_SOURCE_MASK; 601 val |= DREF_SSC_SOURCE_ENABLE; 602 603 /* SSC must be turned on before enabling the CPU output */ 604 if (intel_panel_use_ssc(dev_priv) && can_ssc) { 605 drm_dbg_kms(&dev_priv->drm, "Using SSC on panel\n"); 606 val |= DREF_SSC1_ENABLE; 607 } else { 608 val &= ~DREF_SSC1_ENABLE; 609 } 610 611 /* Get SSC going before enabling the outputs */ 612 intel_de_write(dev_priv, PCH_DREF_CONTROL, val); 613 intel_de_posting_read(dev_priv, PCH_DREF_CONTROL); 614 udelay(200); 615 616 val &= ~DREF_CPU_SOURCE_OUTPUT_MASK; 617 618 /* Enable CPU source on CPU attached eDP */ 619 if (has_cpu_edp) { 620 if (intel_panel_use_ssc(dev_priv) && can_ssc) { 621 drm_dbg_kms(&dev_priv->drm, 622 "Using SSC on eDP\n"); 623 val |= DREF_CPU_SOURCE_OUTPUT_DOWNSPREAD; 624 } else { 625 val |= DREF_CPU_SOURCE_OUTPUT_NONSPREAD; 626 } 627 } else { 628 val |= DREF_CPU_SOURCE_OUTPUT_DISABLE; 629 } 630 631 intel_de_write(dev_priv, PCH_DREF_CONTROL, val); 632 intel_de_posting_read(dev_priv, PCH_DREF_CONTROL); 633 udelay(200); 634 } else { 635 drm_dbg_kms(&dev_priv->drm, "Disabling CPU source output\n"); 636 637 val &= ~DREF_CPU_SOURCE_OUTPUT_MASK; 638 639 /* Turn off CPU output */ 640 val |= DREF_CPU_SOURCE_OUTPUT_DISABLE; 641 642 intel_de_write(dev_priv, PCH_DREF_CONTROL, val); 643 intel_de_posting_read(dev_priv, PCH_DREF_CONTROL); 644 udelay(200); 645 646 if (!using_ssc_source) { 647 drm_dbg_kms(&dev_priv->drm, "Disabling SSC source\n"); 648 649 /* Turn off the SSC source */ 650 val &= ~DREF_SSC_SOURCE_MASK; 651 val |= DREF_SSC_SOURCE_DISABLE; 652 653 /* Turn off SSC1 */ 654 val &= ~DREF_SSC1_ENABLE; 655 656 intel_de_write(dev_priv, PCH_DREF_CONTROL, val); 657 intel_de_posting_read(dev_priv, PCH_DREF_CONTROL); 658 udelay(200); 659 } 660 } 661 662 drm_WARN_ON(&dev_priv->drm, val != final); 663 } 664 665 /* 666 * Initialize reference clocks when the driver loads 667 */ 668 void intel_init_pch_refclk(struct drm_i915_private *dev_priv) 669 { 670 if (HAS_PCH_IBX(dev_priv) || HAS_PCH_CPT(dev_priv)) 671 ilk_init_pch_refclk(dev_priv); 672 else if (HAS_PCH_LPT(dev_priv)) 673 lpt_init_pch_refclk(dev_priv); 674 } 675