xref: /dflybsd-src/sys/dev/drm/i915/intel_pm.c (revision 99ebfb7c19301cfdf9a5a87d225b64586998d69f)
1 /*
2  * Copyright © 2012 Intel Corporation
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21  * IN THE SOFTWARE.
22  *
23  * Authors:
24  *    Eugeni Dodonov <eugeni.dodonov@intel.com>
25  *
26  */
27 
28 #include <drm/drmP.h>
29 #include "intel_drv.h"
30 #include "i915_drv.h"
31 
32 void i8xx_disable_fbc(struct drm_device *dev)
33 {
34 	struct drm_i915_private *dev_priv = dev->dev_private;
35 	u32 fbc_ctl;
36 
37 	/* Disable compression */
38 	fbc_ctl = I915_READ(FBC_CONTROL);
39 	if ((fbc_ctl & FBC_CTL_EN) == 0)
40 		return;
41 
42 	fbc_ctl &= ~FBC_CTL_EN;
43 	I915_WRITE(FBC_CONTROL, fbc_ctl);
44 
45 	/* Wait for compressing bit to clear */
46 	if (_intel_wait_for(dev,
47 	    (I915_READ(FBC_STATUS) & FBC_STAT_COMPRESSING) == 0, 10,
48 	    1, "915fbd")) {
49 		DRM_DEBUG_KMS("FBC idle timed out\n");
50 		return;
51 	}
52 
53 	DRM_DEBUG_KMS("disabled FBC\n");
54 }
55 
56 void i8xx_enable_fbc(struct drm_crtc *crtc, unsigned long interval)
57 {
58 	struct drm_device *dev = crtc->dev;
59 	struct drm_i915_private *dev_priv = dev->dev_private;
60 	struct drm_framebuffer *fb = crtc->fb;
61 	struct intel_framebuffer *intel_fb = to_intel_framebuffer(fb);
62 	struct drm_i915_gem_object *obj = intel_fb->obj;
63 	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
64 	int cfb_pitch;
65 	int plane, i;
66 	u32 fbc_ctl, fbc_ctl2;
67 
68 	cfb_pitch = dev_priv->cfb_size / FBC_LL_SIZE;
69 	if (fb->pitches[0] < cfb_pitch)
70 		cfb_pitch = fb->pitches[0];
71 
72 	/* FBC_CTL wants 64B units */
73 	cfb_pitch = (cfb_pitch / 64) - 1;
74 	plane = intel_crtc->plane == 0 ? FBC_CTL_PLANEA : FBC_CTL_PLANEB;
75 
76 	/* Clear old tags */
77 	for (i = 0; i < (FBC_LL_SIZE / 32) + 1; i++)
78 		I915_WRITE(FBC_TAG + (i * 4), 0);
79 
80 	/* Set it up... */
81 	fbc_ctl2 = FBC_CTL_FENCE_DBL | FBC_CTL_IDLE_IMM | FBC_CTL_CPU_FENCE;
82 	fbc_ctl2 |= plane;
83 	I915_WRITE(FBC_CONTROL2, fbc_ctl2);
84 	I915_WRITE(FBC_FENCE_OFF, crtc->y);
85 
86 	/* enable it... */
87 	fbc_ctl = FBC_CTL_EN | FBC_CTL_PERIODIC;
88 	if (IS_I945GM(dev))
89 		fbc_ctl |= FBC_CTL_C3_IDLE; /* 945 needs special SR handling */
90 	fbc_ctl |= (cfb_pitch & 0xff) << FBC_CTL_STRIDE_SHIFT;
91 	fbc_ctl |= (interval & 0x2fff) << FBC_CTL_INTERVAL_SHIFT;
92 	fbc_ctl |= obj->fence_reg;
93 	I915_WRITE(FBC_CONTROL, fbc_ctl);
94 
95 	DRM_DEBUG_KMS("enabled FBC, pitch %d, yoff %d, plane %d, ",
96 		      cfb_pitch, crtc->y, intel_crtc->plane);
97 }
98 
99 bool i8xx_fbc_enabled(struct drm_device *dev)
100 {
101 	struct drm_i915_private *dev_priv = dev->dev_private;
102 
103 	return I915_READ(FBC_CONTROL) & FBC_CTL_EN;
104 }
105 
106 void g4x_enable_fbc(struct drm_crtc *crtc, unsigned long interval)
107 {
108 	struct drm_device *dev = crtc->dev;
109 	struct drm_i915_private *dev_priv = dev->dev_private;
110 	struct drm_framebuffer *fb = crtc->fb;
111 	struct intel_framebuffer *intel_fb = to_intel_framebuffer(fb);
112 	struct drm_i915_gem_object *obj = intel_fb->obj;
113 	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
114 	int plane = intel_crtc->plane == 0 ? DPFC_CTL_PLANEA : DPFC_CTL_PLANEB;
115 	unsigned long stall_watermark = 200;
116 	u32 dpfc_ctl;
117 
118 	dpfc_ctl = plane | DPFC_SR_EN | DPFC_CTL_LIMIT_1X;
119 	dpfc_ctl |= DPFC_CTL_FENCE_EN | obj->fence_reg;
120 	I915_WRITE(DPFC_CHICKEN, DPFC_HT_MODIFY);
121 
122 	I915_WRITE(DPFC_RECOMP_CTL, DPFC_RECOMP_STALL_EN |
123 		   (stall_watermark << DPFC_RECOMP_STALL_WM_SHIFT) |
124 		   (interval << DPFC_RECOMP_TIMER_COUNT_SHIFT));
125 	I915_WRITE(DPFC_FENCE_YOFF, crtc->y);
126 
127 	/* enable it... */
128 	I915_WRITE(DPFC_CONTROL, I915_READ(DPFC_CONTROL) | DPFC_CTL_EN);
129 
130 	DRM_DEBUG_KMS("enabled fbc on plane %d\n", intel_crtc->plane);
131 }
132 
133 void g4x_disable_fbc(struct drm_device *dev)
134 {
135 	struct drm_i915_private *dev_priv = dev->dev_private;
136 	u32 dpfc_ctl;
137 
138 	/* Disable compression */
139 	dpfc_ctl = I915_READ(DPFC_CONTROL);
140 	if (dpfc_ctl & DPFC_CTL_EN) {
141 		dpfc_ctl &= ~DPFC_CTL_EN;
142 		I915_WRITE(DPFC_CONTROL, dpfc_ctl);
143 
144 		DRM_DEBUG_KMS("disabled FBC\n");
145 	}
146 }
147 
148 bool g4x_fbc_enabled(struct drm_device *dev)
149 {
150 	struct drm_i915_private *dev_priv = dev->dev_private;
151 
152 	return I915_READ(DPFC_CONTROL) & DPFC_CTL_EN;
153 }
154 
155 static void sandybridge_blit_fbc_update(struct drm_device *dev)
156 {
157 	struct drm_i915_private *dev_priv = dev->dev_private;
158 	u32 blt_ecoskpd;
159 
160 	/* Make sure blitter notifies FBC of writes */
161 	gen6_gt_force_wake_get(dev_priv);
162 	blt_ecoskpd = I915_READ(GEN6_BLITTER_ECOSKPD);
163 	blt_ecoskpd |= GEN6_BLITTER_FBC_NOTIFY <<
164 		GEN6_BLITTER_LOCK_SHIFT;
165 	I915_WRITE(GEN6_BLITTER_ECOSKPD, blt_ecoskpd);
166 	blt_ecoskpd |= GEN6_BLITTER_FBC_NOTIFY;
167 	I915_WRITE(GEN6_BLITTER_ECOSKPD, blt_ecoskpd);
168 	blt_ecoskpd &= ~(GEN6_BLITTER_FBC_NOTIFY <<
169 			 GEN6_BLITTER_LOCK_SHIFT);
170 	I915_WRITE(GEN6_BLITTER_ECOSKPD, blt_ecoskpd);
171 	POSTING_READ(GEN6_BLITTER_ECOSKPD);
172 	gen6_gt_force_wake_put(dev_priv);
173 }
174 
175 void ironlake_enable_fbc(struct drm_crtc *crtc, unsigned long interval)
176 {
177 	struct drm_device *dev = crtc->dev;
178 	struct drm_i915_private *dev_priv = dev->dev_private;
179 	struct drm_framebuffer *fb = crtc->fb;
180 	struct intel_framebuffer *intel_fb = to_intel_framebuffer(fb);
181 	struct drm_i915_gem_object *obj = intel_fb->obj;
182 	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
183 	int plane = intel_crtc->plane == 0 ? DPFC_CTL_PLANEA : DPFC_CTL_PLANEB;
184 	unsigned long stall_watermark = 200;
185 	u32 dpfc_ctl;
186 
187 	dpfc_ctl = I915_READ(ILK_DPFC_CONTROL);
188 	dpfc_ctl &= DPFC_RESERVED;
189 	dpfc_ctl |= (plane | DPFC_CTL_LIMIT_1X);
190 	/* Set persistent mode for front-buffer rendering, ala X. */
191 	dpfc_ctl |= DPFC_CTL_PERSISTENT_MODE;
192 	dpfc_ctl |= (DPFC_CTL_FENCE_EN | obj->fence_reg);
193 	I915_WRITE(ILK_DPFC_CHICKEN, DPFC_HT_MODIFY);
194 
195 	I915_WRITE(ILK_DPFC_RECOMP_CTL, DPFC_RECOMP_STALL_EN |
196 		   (stall_watermark << DPFC_RECOMP_STALL_WM_SHIFT) |
197 		   (interval << DPFC_RECOMP_TIMER_COUNT_SHIFT));
198 	I915_WRITE(ILK_DPFC_FENCE_YOFF, crtc->y);
199 	I915_WRITE(ILK_FBC_RT_BASE, obj->gtt_offset | ILK_FBC_RT_VALID);
200 	/* enable it... */
201 	I915_WRITE(ILK_DPFC_CONTROL, dpfc_ctl | DPFC_CTL_EN);
202 
203 	if (IS_GEN6(dev)) {
204 		I915_WRITE(SNB_DPFC_CTL_SA,
205 			   SNB_CPU_FENCE_ENABLE | obj->fence_reg);
206 		I915_WRITE(DPFC_CPU_FENCE_OFFSET, crtc->y);
207 		sandybridge_blit_fbc_update(dev);
208 	}
209 
210 	DRM_DEBUG_KMS("enabled fbc on plane %d\n", intel_crtc->plane);
211 }
212 
213 void ironlake_disable_fbc(struct drm_device *dev)
214 {
215 	struct drm_i915_private *dev_priv = dev->dev_private;
216 	u32 dpfc_ctl;
217 
218 	/* Disable compression */
219 	dpfc_ctl = I915_READ(ILK_DPFC_CONTROL);
220 	if (dpfc_ctl & DPFC_CTL_EN) {
221 		dpfc_ctl &= ~DPFC_CTL_EN;
222 		I915_WRITE(ILK_DPFC_CONTROL, dpfc_ctl);
223 
224 		DRM_DEBUG_KMS("disabled FBC\n");
225 	}
226 }
227 
228 bool ironlake_fbc_enabled(struct drm_device *dev)
229 {
230 	struct drm_i915_private *dev_priv = dev->dev_private;
231 
232 	return I915_READ(ILK_DPFC_CONTROL) & DPFC_CTL_EN;
233 }
234 
235 bool intel_fbc_enabled(struct drm_device *dev)
236 {
237 	struct drm_i915_private *dev_priv = dev->dev_private;
238 
239 	if (!dev_priv->display.fbc_enabled)
240 		return false;
241 
242 	return dev_priv->display.fbc_enabled(dev);
243 }
244 
245 static void intel_fbc_work_fn(struct work_struct *__work)
246 {
247 	struct intel_fbc_work *work =
248 		container_of(to_delayed_work(__work),
249 			     struct intel_fbc_work, work);
250 	struct drm_device *dev = work->crtc->dev;
251 	struct drm_i915_private *dev_priv = dev->dev_private;
252 
253 	DRM_LOCK(dev);
254 	if (work == dev_priv->fbc_work) {
255 		/* Double check that we haven't switched fb without cancelling
256 		 * the prior work.
257 		 */
258 		if (work->crtc->fb == work->fb) {
259 			dev_priv->display.enable_fbc(work->crtc,
260 						     work->interval);
261 
262 			dev_priv->cfb_plane = to_intel_crtc(work->crtc)->plane;
263 			dev_priv->cfb_fb = work->crtc->fb->base.id;
264 			dev_priv->cfb_y = work->crtc->y;
265 		}
266 
267 		dev_priv->fbc_work = NULL;
268 	}
269 	DRM_UNLOCK(dev);
270 
271 	drm_free(work, DRM_MEM_KMS);
272 }
273 
274 static void intel_cancel_fbc_work(struct drm_i915_private *dev_priv)
275 {
276 	if (dev_priv->fbc_work == NULL)
277 		return;
278 
279 	DRM_DEBUG_KMS("cancelling pending FBC enable\n");
280 
281 	/* Synchronisation is provided by struct_mutex and checking of
282 	 * dev_priv->fbc_work, so we can perform the cancellation
283 	 * entirely asynchronously.
284 	 */
285 	if (cancel_delayed_work(&dev_priv->fbc_work->work))
286 		/* tasklet was killed before being run, clean up */
287 		kfree(dev_priv->fbc_work, DRM_MEM_KMS);
288 
289 	/* Mark the work as no longer wanted so that if it does
290 	 * wake-up (because the work was already running and waiting
291 	 * for our mutex), it will discover that is no longer
292 	 * necessary to run.
293 	 */
294 	dev_priv->fbc_work = NULL;
295 }
296 
297 void intel_enable_fbc(struct drm_crtc *crtc, unsigned long interval)
298 {
299 	struct intel_fbc_work *work;
300 	struct drm_device *dev = crtc->dev;
301 	struct drm_i915_private *dev_priv = dev->dev_private;
302 
303 	if (!dev_priv->display.enable_fbc)
304 		return;
305 
306 	intel_cancel_fbc_work(dev_priv);
307 
308 	work = kmalloc(sizeof(*work), DRM_MEM_KMS, M_WAITOK | M_ZERO);
309 	work->crtc = crtc;
310 	work->fb = crtc->fb;
311 	work->interval = interval;
312 	INIT_DELAYED_WORK(&work->work, intel_fbc_work_fn);
313 
314 	dev_priv->fbc_work = work;
315 
316 	DRM_DEBUG_KMS("scheduling delayed FBC enable\n");
317 
318 	/* Delay the actual enabling to let pageflipping cease and the
319 	 * display to settle before starting the compression. Note that
320 	 * this delay also serves a second purpose: it allows for a
321 	 * vblank to pass after disabling the FBC before we attempt
322 	 * to modify the control registers.
323 	 *
324 	 * A more complicated solution would involve tracking vblanks
325 	 * following the termination of the page-flipping sequence
326 	 * and indeed performing the enable as a co-routine and not
327 	 * waiting synchronously upon the vblank.
328 	 */
329 	schedule_delayed_work(&work->work, msecs_to_jiffies(50));
330 }
331 
332 void intel_disable_fbc(struct drm_device *dev)
333 {
334 	struct drm_i915_private *dev_priv = dev->dev_private;
335 
336 	intel_cancel_fbc_work(dev_priv);
337 
338 	if (!dev_priv->display.disable_fbc)
339 		return;
340 
341 	dev_priv->display.disable_fbc(dev);
342 	dev_priv->cfb_plane = -1;
343 }
344 
345 /**
346  * intel_update_fbc - enable/disable FBC as needed
347  * @dev: the drm_device
348  *
349  * Set up the framebuffer compression hardware at mode set time.  We
350  * enable it if possible:
351  *   - plane A only (on pre-965)
352  *   - no pixel mulitply/line duplication
353  *   - no alpha buffer discard
354  *   - no dual wide
355  *   - framebuffer <= 2048 in width, 1536 in height
356  *
357  * We can't assume that any compression will take place (worst case),
358  * so the compressed buffer has to be the same size as the uncompressed
359  * one.  It also must reside (along with the line length buffer) in
360  * stolen memory.
361  *
362  * We need to enable/disable FBC on a global basis.
363  */
364 void intel_update_fbc(struct drm_device *dev)
365 {
366 	struct drm_i915_private *dev_priv = dev->dev_private;
367 	struct drm_crtc *crtc = NULL, *tmp_crtc;
368 	struct intel_crtc *intel_crtc;
369 	struct drm_framebuffer *fb;
370 	struct intel_framebuffer *intel_fb;
371 	struct drm_i915_gem_object *obj;
372 	int enable_fbc;
373 
374 	DRM_DEBUG_KMS("\n");
375 
376 	if (!i915_powersave)
377 		return;
378 
379 	if (!I915_HAS_FBC(dev))
380 		return;
381 
382 	/*
383 	 * If FBC is already on, we just have to verify that we can
384 	 * keep it that way...
385 	 * Need to disable if:
386 	 *   - more than one pipe is active
387 	 *   - changing FBC params (stride, fence, mode)
388 	 *   - new fb is too large to fit in compressed buffer
389 	 *   - going to an unsupported config (interlace, pixel multiply, etc.)
390 	 */
391 	list_for_each_entry(tmp_crtc, &dev->mode_config.crtc_list, head) {
392 		if (tmp_crtc->enabled && tmp_crtc->fb) {
393 			if (crtc) {
394 				DRM_DEBUG_KMS("more than one pipe active, disabling compression\n");
395 				dev_priv->no_fbc_reason = FBC_MULTIPLE_PIPES;
396 				goto out_disable;
397 			}
398 			crtc = tmp_crtc;
399 		}
400 	}
401 
402 	if (!crtc || crtc->fb == NULL) {
403 		DRM_DEBUG_KMS("no output, disabling\n");
404 		dev_priv->no_fbc_reason = FBC_NO_OUTPUT;
405 		goto out_disable;
406 	}
407 
408 	intel_crtc = to_intel_crtc(crtc);
409 	fb = crtc->fb;
410 	intel_fb = to_intel_framebuffer(fb);
411 	obj = intel_fb->obj;
412 
413 	enable_fbc = i915_enable_fbc;
414 	if (enable_fbc < 0) {
415 		DRM_DEBUG_KMS("fbc set to per-chip default\n");
416 		enable_fbc = 1;
417 		if (INTEL_INFO(dev)->gen <= 6)
418 			enable_fbc = 0;
419 	}
420 	if (!enable_fbc) {
421 		DRM_DEBUG_KMS("fbc disabled per module param\n");
422 		dev_priv->no_fbc_reason = FBC_MODULE_PARAM;
423 		goto out_disable;
424 	}
425 	if (intel_fb->obj->base.size > dev_priv->cfb_size) {
426 		DRM_DEBUG_KMS("framebuffer too large, disabling "
427 			      "compression\n");
428 		dev_priv->no_fbc_reason = FBC_STOLEN_TOO_SMALL;
429 		goto out_disable;
430 	}
431 	if ((crtc->mode.flags & DRM_MODE_FLAG_INTERLACE) ||
432 	    (crtc->mode.flags & DRM_MODE_FLAG_DBLSCAN)) {
433 		DRM_DEBUG_KMS("mode incompatible with compression, "
434 			      "disabling\n");
435 		dev_priv->no_fbc_reason = FBC_UNSUPPORTED_MODE;
436 		goto out_disable;
437 	}
438 	if ((crtc->mode.hdisplay > 2048) ||
439 	    (crtc->mode.vdisplay > 1536)) {
440 		DRM_DEBUG_KMS("mode too large for compression, disabling\n");
441 		dev_priv->no_fbc_reason = FBC_MODE_TOO_LARGE;
442 		goto out_disable;
443 	}
444 	if ((IS_I915GM(dev) || IS_I945GM(dev)) && intel_crtc->plane != 0) {
445 		DRM_DEBUG_KMS("plane not 0, disabling compression\n");
446 		dev_priv->no_fbc_reason = FBC_BAD_PLANE;
447 		goto out_disable;
448 	}
449 	if (obj->tiling_mode != I915_TILING_X ||
450 	    obj->fence_reg == I915_FENCE_REG_NONE) {
451 		DRM_DEBUG_KMS("framebuffer not tiled or fenced, disabling compression\n");
452 		dev_priv->no_fbc_reason = FBC_NOT_TILED;
453 		goto out_disable;
454 	}
455 
456 #ifdef DDB
457 	/* If the kernel debugger is active, always disable compression */
458 	if (db_active)
459 		goto out_disable;
460 #endif
461 
462 	/* If the scanout has not changed, don't modify the FBC settings.
463 	 * Note that we make the fundamental assumption that the fb->obj
464 	 * cannot be unpinned (and have its GTT offset and fence revoked)
465 	 * without first being decoupled from the scanout and FBC disabled.
466 	 */
467 	if (dev_priv->cfb_plane == intel_crtc->plane &&
468 	    dev_priv->cfb_fb == fb->base.id &&
469 	    dev_priv->cfb_y == crtc->y)
470 		return;
471 
472 	if (intel_fbc_enabled(dev)) {
473 		/* We update FBC along two paths, after changing fb/crtc
474 		 * configuration (modeswitching) and after page-flipping
475 		 * finishes. For the latter, we know that not only did
476 		 * we disable the FBC at the start of the page-flip
477 		 * sequence, but also more than one vblank has passed.
478 		 *
479 		 * For the former case of modeswitching, it is possible
480 		 * to switch between two FBC valid configurations
481 		 * instantaneously so we do need to disable the FBC
482 		 * before we can modify its control registers. We also
483 		 * have to wait for the next vblank for that to take
484 		 * effect. However, since we delay enabling FBC we can
485 		 * assume that a vblank has passed since disabling and
486 		 * that we can safely alter the registers in the deferred
487 		 * callback.
488 		 *
489 		 * In the scenario that we go from a valid to invalid
490 		 * and then back to valid FBC configuration we have
491 		 * no strict enforcement that a vblank occurred since
492 		 * disabling the FBC. However, along all current pipe
493 		 * disabling paths we do need to wait for a vblank at
494 		 * some point. And we wait before enabling FBC anyway.
495 		 */
496 		DRM_DEBUG_KMS("disabling active FBC for update\n");
497 		intel_disable_fbc(dev);
498 	}
499 
500 	intel_enable_fbc(crtc, 500);
501 	return;
502 
503 out_disable:
504 	/* Multiple disables should be harmless */
505 	if (intel_fbc_enabled(dev)) {
506 		DRM_DEBUG_KMS("unsupported config, disabling FBC\n");
507 		intel_disable_fbc(dev);
508 	}
509 }
510 
511 void i915_ironlake_get_mem_freq(struct drm_device *dev);
512 void i915_pineview_get_mem_freq(struct drm_device *dev);
513 
514 void i915_pineview_get_mem_freq(struct drm_device *dev)
515 {
516 	drm_i915_private_t *dev_priv = dev->dev_private;
517 	u32 tmp;
518 
519 	tmp = I915_READ(CLKCFG);
520 
521 	switch (tmp & CLKCFG_FSB_MASK) {
522 	case CLKCFG_FSB_533:
523 		dev_priv->fsb_freq = 533; /* 133*4 */
524 		break;
525 	case CLKCFG_FSB_800:
526 		dev_priv->fsb_freq = 800; /* 200*4 */
527 		break;
528 	case CLKCFG_FSB_667:
529 		dev_priv->fsb_freq =  667; /* 167*4 */
530 		break;
531 	case CLKCFG_FSB_400:
532 		dev_priv->fsb_freq = 400; /* 100*4 */
533 		break;
534 	}
535 
536 	switch (tmp & CLKCFG_MEM_MASK) {
537 	case CLKCFG_MEM_533:
538 		dev_priv->mem_freq = 533;
539 		break;
540 	case CLKCFG_MEM_667:
541 		dev_priv->mem_freq = 667;
542 		break;
543 	case CLKCFG_MEM_800:
544 		dev_priv->mem_freq = 800;
545 		break;
546 	}
547 
548 	/* detect pineview DDR3 setting */
549 	tmp = I915_READ(CSHRDDR3CTL);
550 	dev_priv->is_ddr3 = (tmp & CSHRDDR3CTL_DDR3) ? 1 : 0;
551 }
552 
553 void i915_ironlake_get_mem_freq(struct drm_device *dev)
554 {
555 	drm_i915_private_t *dev_priv = dev->dev_private;
556 	u16 ddrpll, csipll;
557 
558 	ddrpll = I915_READ16(DDRMPLL1);
559 	csipll = I915_READ16(CSIPLL0);
560 
561 	switch (ddrpll & 0xff) {
562 	case 0xc:
563 		dev_priv->mem_freq = 800;
564 		break;
565 	case 0x10:
566 		dev_priv->mem_freq = 1066;
567 		break;
568 	case 0x14:
569 		dev_priv->mem_freq = 1333;
570 		break;
571 	case 0x18:
572 		dev_priv->mem_freq = 1600;
573 		break;
574 	default:
575 		DRM_DEBUG("unknown memory frequency 0x%02x\n",
576 				 ddrpll & 0xff);
577 		dev_priv->mem_freq = 0;
578 		break;
579 	}
580 
581 	dev_priv->r_t = dev_priv->mem_freq;
582 
583 	switch (csipll & 0x3ff) {
584 	case 0x00c:
585 		dev_priv->fsb_freq = 3200;
586 		break;
587 	case 0x00e:
588 		dev_priv->fsb_freq = 3733;
589 		break;
590 	case 0x010:
591 		dev_priv->fsb_freq = 4266;
592 		break;
593 	case 0x012:
594 		dev_priv->fsb_freq = 4800;
595 		break;
596 	case 0x014:
597 		dev_priv->fsb_freq = 5333;
598 		break;
599 	case 0x016:
600 		dev_priv->fsb_freq = 5866;
601 		break;
602 	case 0x018:
603 		dev_priv->fsb_freq = 6400;
604 		break;
605 	default:
606 		DRM_DEBUG("unknown fsb frequency 0x%04x\n",
607 				 csipll & 0x3ff);
608 		dev_priv->fsb_freq = 0;
609 		break;
610 	}
611 
612 	if (dev_priv->fsb_freq == 3200) {
613 		dev_priv->c_m = 0;
614 	} else if (dev_priv->fsb_freq > 3200 && dev_priv->fsb_freq <= 4800) {
615 		dev_priv->c_m = 1;
616 	} else {
617 		dev_priv->c_m = 2;
618 	}
619 }
620 
621 /* Pineview has different values for various configs */
622 static const struct intel_watermark_params pineview_display_wm = {
623 	PINEVIEW_DISPLAY_FIFO,
624 	PINEVIEW_MAX_WM,
625 	PINEVIEW_DFT_WM,
626 	PINEVIEW_GUARD_WM,
627 	PINEVIEW_FIFO_LINE_SIZE
628 };
629 static const struct intel_watermark_params pineview_display_hplloff_wm = {
630 	PINEVIEW_DISPLAY_FIFO,
631 	PINEVIEW_MAX_WM,
632 	PINEVIEW_DFT_HPLLOFF_WM,
633 	PINEVIEW_GUARD_WM,
634 	PINEVIEW_FIFO_LINE_SIZE
635 };
636 static const struct intel_watermark_params pineview_cursor_wm = {
637 	PINEVIEW_CURSOR_FIFO,
638 	PINEVIEW_CURSOR_MAX_WM,
639 	PINEVIEW_CURSOR_DFT_WM,
640 	PINEVIEW_CURSOR_GUARD_WM,
641 	PINEVIEW_FIFO_LINE_SIZE,
642 };
643 static const struct intel_watermark_params pineview_cursor_hplloff_wm = {
644 	PINEVIEW_CURSOR_FIFO,
645 	PINEVIEW_CURSOR_MAX_WM,
646 	PINEVIEW_CURSOR_DFT_WM,
647 	PINEVIEW_CURSOR_GUARD_WM,
648 	PINEVIEW_FIFO_LINE_SIZE
649 };
650 static const struct intel_watermark_params g4x_wm_info = {
651 	G4X_FIFO_SIZE,
652 	G4X_MAX_WM,
653 	G4X_MAX_WM,
654 	2,
655 	G4X_FIFO_LINE_SIZE,
656 };
657 static const struct intel_watermark_params g4x_cursor_wm_info = {
658 	I965_CURSOR_FIFO,
659 	I965_CURSOR_MAX_WM,
660 	I965_CURSOR_DFT_WM,
661 	2,
662 	G4X_FIFO_LINE_SIZE,
663 };
664 static const struct intel_watermark_params i965_cursor_wm_info = {
665 	I965_CURSOR_FIFO,
666 	I965_CURSOR_MAX_WM,
667 	I965_CURSOR_DFT_WM,
668 	2,
669 	I915_FIFO_LINE_SIZE,
670 };
671 static const struct intel_watermark_params i945_wm_info = {
672 	I945_FIFO_SIZE,
673 	I915_MAX_WM,
674 	1,
675 	2,
676 	I915_FIFO_LINE_SIZE
677 };
678 static const struct intel_watermark_params i915_wm_info = {
679 	I915_FIFO_SIZE,
680 	I915_MAX_WM,
681 	1,
682 	2,
683 	I915_FIFO_LINE_SIZE
684 };
685 static const struct intel_watermark_params i855_wm_info = {
686 	I855GM_FIFO_SIZE,
687 	I915_MAX_WM,
688 	1,
689 	2,
690 	I830_FIFO_LINE_SIZE
691 };
692 static const struct intel_watermark_params i830_wm_info = {
693 	I830_FIFO_SIZE,
694 	I915_MAX_WM,
695 	1,
696 	2,
697 	I830_FIFO_LINE_SIZE
698 };
699 
700 static const struct intel_watermark_params ironlake_display_wm_info = {
701 	ILK_DISPLAY_FIFO,
702 	ILK_DISPLAY_MAXWM,
703 	ILK_DISPLAY_DFTWM,
704 	2,
705 	ILK_FIFO_LINE_SIZE
706 };
707 static const struct intel_watermark_params ironlake_cursor_wm_info = {
708 	ILK_CURSOR_FIFO,
709 	ILK_CURSOR_MAXWM,
710 	ILK_CURSOR_DFTWM,
711 	2,
712 	ILK_FIFO_LINE_SIZE
713 };
714 static const struct intel_watermark_params ironlake_display_srwm_info = {
715 	ILK_DISPLAY_SR_FIFO,
716 	ILK_DISPLAY_MAX_SRWM,
717 	ILK_DISPLAY_DFT_SRWM,
718 	2,
719 	ILK_FIFO_LINE_SIZE
720 };
721 static const struct intel_watermark_params ironlake_cursor_srwm_info = {
722 	ILK_CURSOR_SR_FIFO,
723 	ILK_CURSOR_MAX_SRWM,
724 	ILK_CURSOR_DFT_SRWM,
725 	2,
726 	ILK_FIFO_LINE_SIZE
727 };
728 
729 static const struct intel_watermark_params sandybridge_display_wm_info = {
730 	SNB_DISPLAY_FIFO,
731 	SNB_DISPLAY_MAXWM,
732 	SNB_DISPLAY_DFTWM,
733 	2,
734 	SNB_FIFO_LINE_SIZE
735 };
736 static const struct intel_watermark_params sandybridge_cursor_wm_info = {
737 	SNB_CURSOR_FIFO,
738 	SNB_CURSOR_MAXWM,
739 	SNB_CURSOR_DFTWM,
740 	2,
741 	SNB_FIFO_LINE_SIZE
742 };
743 static const struct intel_watermark_params sandybridge_display_srwm_info = {
744 	SNB_DISPLAY_SR_FIFO,
745 	SNB_DISPLAY_MAX_SRWM,
746 	SNB_DISPLAY_DFT_SRWM,
747 	2,
748 	SNB_FIFO_LINE_SIZE
749 };
750 static const struct intel_watermark_params sandybridge_cursor_srwm_info = {
751 	SNB_CURSOR_SR_FIFO,
752 	SNB_CURSOR_MAX_SRWM,
753 	SNB_CURSOR_DFT_SRWM,
754 	2,
755 	SNB_FIFO_LINE_SIZE
756 };
757 
758 
759 /**
760  * intel_calculate_wm - calculate watermark level
761  * @clock_in_khz: pixel clock
762  * @wm: chip FIFO params
763  * @pixel_size: display pixel size
764  * @latency_ns: memory latency for the platform
765  *
766  * Calculate the watermark level (the level at which the display plane will
767  * start fetching from memory again).  Each chip has a different display
768  * FIFO size and allocation, so the caller needs to figure that out and pass
769  * in the correct intel_watermark_params structure.
770  *
771  * As the pixel clock runs, the FIFO will be drained at a rate that depends
772  * on the pixel size.  When it reaches the watermark level, it'll start
773  * fetching FIFO line sized based chunks from memory until the FIFO fills
774  * past the watermark point.  If the FIFO drains completely, a FIFO underrun
775  * will occur, and a display engine hang could result.
776  */
777 static unsigned long intel_calculate_wm(unsigned long clock_in_khz,
778 					const struct intel_watermark_params *wm,
779 					int fifo_size,
780 					int pixel_size,
781 					unsigned long latency_ns)
782 {
783 	long entries_required, wm_size;
784 
785 	/*
786 	 * Note: we need to make sure we don't overflow for various clock &
787 	 * latency values.
788 	 * clocks go from a few thousand to several hundred thousand.
789 	 * latency is usually a few thousand
790 	 */
791 	entries_required = ((clock_in_khz / 1000) * pixel_size * latency_ns) /
792 		1000;
793 	entries_required = howmany(entries_required, wm->cacheline_size);
794 
795 	DRM_DEBUG_KMS("FIFO entries required for mode: %ld\n", entries_required);
796 
797 	wm_size = fifo_size - (entries_required + wm->guard_size);
798 
799 	DRM_DEBUG_KMS("FIFO watermark level: %ld\n", wm_size);
800 
801 	/* Don't promote wm_size to unsigned... */
802 	if (wm_size > (long)wm->max_wm)
803 		wm_size = wm->max_wm;
804 	if (wm_size <= 0)
805 		wm_size = wm->default_wm;
806 	return wm_size;
807 }
808 
809 struct cxsr_latency {
810 	int is_desktop;
811 	int is_ddr3;
812 	unsigned long fsb_freq;
813 	unsigned long mem_freq;
814 	unsigned long display_sr;
815 	unsigned long display_hpll_disable;
816 	unsigned long cursor_sr;
817 	unsigned long cursor_hpll_disable;
818 };
819 
820 static const struct cxsr_latency cxsr_latency_table[] = {
821 	{1, 0, 800, 400, 3382, 33382, 3983, 33983},    /* DDR2-400 SC */
822 	{1, 0, 800, 667, 3354, 33354, 3807, 33807},    /* DDR2-667 SC */
823 	{1, 0, 800, 800, 3347, 33347, 3763, 33763},    /* DDR2-800 SC */
824 	{1, 1, 800, 667, 6420, 36420, 6873, 36873},    /* DDR3-667 SC */
825 	{1, 1, 800, 800, 5902, 35902, 6318, 36318},    /* DDR3-800 SC */
826 
827 	{1, 0, 667, 400, 3400, 33400, 4021, 34021},    /* DDR2-400 SC */
828 	{1, 0, 667, 667, 3372, 33372, 3845, 33845},    /* DDR2-667 SC */
829 	{1, 0, 667, 800, 3386, 33386, 3822, 33822},    /* DDR2-800 SC */
830 	{1, 1, 667, 667, 6438, 36438, 6911, 36911},    /* DDR3-667 SC */
831 	{1, 1, 667, 800, 5941, 35941, 6377, 36377},    /* DDR3-800 SC */
832 
833 	{1, 0, 400, 400, 3472, 33472, 4173, 34173},    /* DDR2-400 SC */
834 	{1, 0, 400, 667, 3443, 33443, 3996, 33996},    /* DDR2-667 SC */
835 	{1, 0, 400, 800, 3430, 33430, 3946, 33946},    /* DDR2-800 SC */
836 	{1, 1, 400, 667, 6509, 36509, 7062, 37062},    /* DDR3-667 SC */
837 	{1, 1, 400, 800, 5985, 35985, 6501, 36501},    /* DDR3-800 SC */
838 
839 	{0, 0, 800, 400, 3438, 33438, 4065, 34065},    /* DDR2-400 SC */
840 	{0, 0, 800, 667, 3410, 33410, 3889, 33889},    /* DDR2-667 SC */
841 	{0, 0, 800, 800, 3403, 33403, 3845, 33845},    /* DDR2-800 SC */
842 	{0, 1, 800, 667, 6476, 36476, 6955, 36955},    /* DDR3-667 SC */
843 	{0, 1, 800, 800, 5958, 35958, 6400, 36400},    /* DDR3-800 SC */
844 
845 	{0, 0, 667, 400, 3456, 33456, 4103, 34106},    /* DDR2-400 SC */
846 	{0, 0, 667, 667, 3428, 33428, 3927, 33927},    /* DDR2-667 SC */
847 	{0, 0, 667, 800, 3443, 33443, 3905, 33905},    /* DDR2-800 SC */
848 	{0, 1, 667, 667, 6494, 36494, 6993, 36993},    /* DDR3-667 SC */
849 	{0, 1, 667, 800, 5998, 35998, 6460, 36460},    /* DDR3-800 SC */
850 
851 	{0, 0, 400, 400, 3528, 33528, 4255, 34255},    /* DDR2-400 SC */
852 	{0, 0, 400, 667, 3500, 33500, 4079, 34079},    /* DDR2-667 SC */
853 	{0, 0, 400, 800, 3487, 33487, 4029, 34029},    /* DDR2-800 SC */
854 	{0, 1, 400, 667, 6566, 36566, 7145, 37145},    /* DDR3-667 SC */
855 	{0, 1, 400, 800, 6042, 36042, 6584, 36584},    /* DDR3-800 SC */
856 };
857 
858 const struct cxsr_latency *intel_get_cxsr_latency(int is_desktop,
859 							 int is_ddr3,
860 							 int fsb,
861 							 int mem)
862 {
863 	const struct cxsr_latency *latency;
864 	int i;
865 
866 	if (fsb == 0 || mem == 0)
867 		return NULL;
868 
869 	for (i = 0; i < DRM_ARRAY_SIZE(cxsr_latency_table); i++) {
870 		latency = &cxsr_latency_table[i];
871 		if (is_desktop == latency->is_desktop &&
872 		    is_ddr3 == latency->is_ddr3 &&
873 		    fsb == latency->fsb_freq && mem == latency->mem_freq)
874 			return latency;
875 	}
876 
877 	DRM_DEBUG_KMS("Unknown FSB/MEM found, disable CxSR\n");
878 
879 	return NULL;
880 }
881 
882 void pineview_disable_cxsr(struct drm_device *dev)
883 {
884 	struct drm_i915_private *dev_priv = dev->dev_private;
885 
886 	/* deactivate cxsr */
887 	I915_WRITE(DSPFW3, I915_READ(DSPFW3) & ~PINEVIEW_SELF_REFRESH_EN);
888 }
889 
890 /*
891  * Latency for FIFO fetches is dependent on several factors:
892  *   - memory configuration (speed, channels)
893  *   - chipset
894  *   - current MCH state
895  * It can be fairly high in some situations, so here we assume a fairly
896  * pessimal value.  It's a tradeoff between extra memory fetches (if we
897  * set this value too high, the FIFO will fetch frequently to stay full)
898  * and power consumption (set it too low to save power and we might see
899  * FIFO underruns and display "flicker").
900  *
901  * A value of 5us seems to be a good balance; safe for very low end
902  * platforms but not overly aggressive on lower latency configs.
903  */
904 static const int latency_ns = 5000;
905 
906 int i9xx_get_fifo_size(struct drm_device *dev, int plane)
907 {
908 	struct drm_i915_private *dev_priv = dev->dev_private;
909 	uint32_t dsparb = I915_READ(DSPARB);
910 	int size;
911 
912 	size = dsparb & 0x7f;
913 	if (plane)
914 		size = ((dsparb >> DSPARB_CSTART_SHIFT) & 0x7f) - size;
915 
916 	DRM_DEBUG_KMS("FIFO size - (0x%08x) %s: %d\n", dsparb,
917 		      plane ? "B" : "A", size);
918 
919 	return size;
920 }
921 
922 int i85x_get_fifo_size(struct drm_device *dev, int plane)
923 {
924 	struct drm_i915_private *dev_priv = dev->dev_private;
925 	uint32_t dsparb = I915_READ(DSPARB);
926 	int size;
927 
928 	size = dsparb & 0x1ff;
929 	if (plane)
930 		size = ((dsparb >> DSPARB_BEND_SHIFT) & 0x1ff) - size;
931 	size >>= 1; /* Convert to cachelines */
932 
933 	DRM_DEBUG_KMS("FIFO size - (0x%08x) %s: %d\n", dsparb,
934 		      plane ? "B" : "A", size);
935 
936 	return size;
937 }
938 
939 int i845_get_fifo_size(struct drm_device *dev, int plane)
940 {
941 	struct drm_i915_private *dev_priv = dev->dev_private;
942 	uint32_t dsparb = I915_READ(DSPARB);
943 	int size;
944 
945 	size = dsparb & 0x7f;
946 	size >>= 2; /* Convert to cachelines */
947 
948 	DRM_DEBUG_KMS("FIFO size - (0x%08x) %s: %d\n", dsparb,
949 		      plane ? "B" : "A",
950 		      size);
951 
952 	return size;
953 }
954 
955 int i830_get_fifo_size(struct drm_device *dev, int plane)
956 {
957 	struct drm_i915_private *dev_priv = dev->dev_private;
958 	uint32_t dsparb = I915_READ(DSPARB);
959 	int size;
960 
961 	size = dsparb & 0x7f;
962 	size >>= 1; /* Convert to cachelines */
963 
964 	DRM_DEBUG_KMS("FIFO size - (0x%08x) %s: %d\n", dsparb,
965 		      plane ? "B" : "A", size);
966 
967 	return size;
968 }
969 
970 static struct drm_crtc *single_enabled_crtc(struct drm_device *dev)
971 {
972 	struct drm_crtc *crtc, *enabled = NULL;
973 
974 	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
975 		if (crtc->enabled && crtc->fb) {
976 			if (enabled)
977 				return NULL;
978 			enabled = crtc;
979 		}
980 	}
981 
982 	return enabled;
983 }
984 
985 void pineview_update_wm(struct drm_device *dev)
986 {
987 	struct drm_i915_private *dev_priv = dev->dev_private;
988 	struct drm_crtc *crtc;
989 	const struct cxsr_latency *latency;
990 	u32 reg;
991 	unsigned long wm;
992 
993 	latency = intel_get_cxsr_latency(IS_PINEVIEW_G(dev), dev_priv->is_ddr3,
994 					 dev_priv->fsb_freq, dev_priv->mem_freq);
995 	if (!latency) {
996 		DRM_DEBUG_KMS("Unknown FSB/MEM found, disable CxSR\n");
997 		pineview_disable_cxsr(dev);
998 		return;
999 	}
1000 
1001 	crtc = single_enabled_crtc(dev);
1002 	if (crtc) {
1003 		int clock = crtc->mode.clock;
1004 		int pixel_size = crtc->fb->bits_per_pixel / 8;
1005 
1006 		/* Display SR */
1007 		wm = intel_calculate_wm(clock, &pineview_display_wm,
1008 					pineview_display_wm.fifo_size,
1009 					pixel_size, latency->display_sr);
1010 		reg = I915_READ(DSPFW1);
1011 		reg &= ~DSPFW_SR_MASK;
1012 		reg |= wm << DSPFW_SR_SHIFT;
1013 		I915_WRITE(DSPFW1, reg);
1014 		DRM_DEBUG_KMS("DSPFW1 register is %x\n", reg);
1015 
1016 		/* cursor SR */
1017 		wm = intel_calculate_wm(clock, &pineview_cursor_wm,
1018 					pineview_display_wm.fifo_size,
1019 					pixel_size, latency->cursor_sr);
1020 		reg = I915_READ(DSPFW3);
1021 		reg &= ~DSPFW_CURSOR_SR_MASK;
1022 		reg |= (wm & 0x3f) << DSPFW_CURSOR_SR_SHIFT;
1023 		I915_WRITE(DSPFW3, reg);
1024 
1025 		/* Display HPLL off SR */
1026 		wm = intel_calculate_wm(clock, &pineview_display_hplloff_wm,
1027 					pineview_display_hplloff_wm.fifo_size,
1028 					pixel_size, latency->display_hpll_disable);
1029 		reg = I915_READ(DSPFW3);
1030 		reg &= ~DSPFW_HPLL_SR_MASK;
1031 		reg |= wm & DSPFW_HPLL_SR_MASK;
1032 		I915_WRITE(DSPFW3, reg);
1033 
1034 		/* cursor HPLL off SR */
1035 		wm = intel_calculate_wm(clock, &pineview_cursor_hplloff_wm,
1036 					pineview_display_hplloff_wm.fifo_size,
1037 					pixel_size, latency->cursor_hpll_disable);
1038 		reg = I915_READ(DSPFW3);
1039 		reg &= ~DSPFW_HPLL_CURSOR_MASK;
1040 		reg |= (wm & 0x3f) << DSPFW_HPLL_CURSOR_SHIFT;
1041 		I915_WRITE(DSPFW3, reg);
1042 		DRM_DEBUG_KMS("DSPFW3 register is %x\n", reg);
1043 
1044 		/* activate cxsr */
1045 		I915_WRITE(DSPFW3,
1046 			   I915_READ(DSPFW3) | PINEVIEW_SELF_REFRESH_EN);
1047 		DRM_DEBUG_KMS("Self-refresh is enabled\n");
1048 	} else {
1049 		pineview_disable_cxsr(dev);
1050 		DRM_DEBUG_KMS("Self-refresh is disabled\n");
1051 	}
1052 }
1053 
1054 static bool g4x_compute_wm0(struct drm_device *dev,
1055 			    int plane,
1056 			    const struct intel_watermark_params *display,
1057 			    int display_latency_ns,
1058 			    const struct intel_watermark_params *cursor,
1059 			    int cursor_latency_ns,
1060 			    int *plane_wm,
1061 			    int *cursor_wm)
1062 {
1063 	struct drm_crtc *crtc;
1064 	int htotal, hdisplay, clock, pixel_size;
1065 	int line_time_us, line_count;
1066 	int entries, tlb_miss;
1067 
1068 	crtc = intel_get_crtc_for_plane(dev, plane);
1069 	if (crtc->fb == NULL || !crtc->enabled) {
1070 		*cursor_wm = cursor->guard_size;
1071 		*plane_wm = display->guard_size;
1072 		return false;
1073 	}
1074 
1075 	htotal = crtc->mode.htotal;
1076 	hdisplay = crtc->mode.hdisplay;
1077 	clock = crtc->mode.clock;
1078 	pixel_size = crtc->fb->bits_per_pixel / 8;
1079 
1080 	/* Use the small buffer method to calculate plane watermark */
1081 	entries = ((clock * pixel_size / 1000) * display_latency_ns) / 1000;
1082 	tlb_miss = display->fifo_size*display->cacheline_size - hdisplay * 8;
1083 	if (tlb_miss > 0)
1084 		entries += tlb_miss;
1085 	entries = howmany(entries, display->cacheline_size);
1086 	*plane_wm = entries + display->guard_size;
1087 	if (*plane_wm > (int)display->max_wm)
1088 		*plane_wm = display->max_wm;
1089 
1090 	/* Use the large buffer method to calculate cursor watermark */
1091 	line_time_us = ((htotal * 1000) / clock);
1092 	line_count = (cursor_latency_ns / line_time_us + 1000) / 1000;
1093 	entries = line_count * 64 * pixel_size;
1094 	tlb_miss = cursor->fifo_size*cursor->cacheline_size - hdisplay * 8;
1095 	if (tlb_miss > 0)
1096 		entries += tlb_miss;
1097 	entries = howmany(entries, cursor->cacheline_size);
1098 	*cursor_wm = entries + cursor->guard_size;
1099 	if (*cursor_wm > (int)cursor->max_wm)
1100 		*cursor_wm = (int)cursor->max_wm;
1101 
1102 	return true;
1103 }
1104 
1105 /*
1106  * Check the wm result.
1107  *
1108  * If any calculated watermark values is larger than the maximum value that
1109  * can be programmed into the associated watermark register, that watermark
1110  * must be disabled.
1111  */
1112 static bool g4x_check_srwm(struct drm_device *dev,
1113 			   int display_wm, int cursor_wm,
1114 			   const struct intel_watermark_params *display,
1115 			   const struct intel_watermark_params *cursor)
1116 {
1117 	DRM_DEBUG_KMS("SR watermark: display plane %d, cursor %d\n",
1118 		      display_wm, cursor_wm);
1119 
1120 	if (display_wm > display->max_wm) {
1121 		DRM_DEBUG_KMS("display watermark is too large(%d/%ld), disabling\n",
1122 			      display_wm, display->max_wm);
1123 		return false;
1124 	}
1125 
1126 	if (cursor_wm > cursor->max_wm) {
1127 		DRM_DEBUG_KMS("cursor watermark is too large(%d/%ld), disabling\n",
1128 			      cursor_wm, cursor->max_wm);
1129 		return false;
1130 	}
1131 
1132 	if (!(display_wm || cursor_wm)) {
1133 		DRM_DEBUG_KMS("SR latency is 0, disabling\n");
1134 		return false;
1135 	}
1136 
1137 	return true;
1138 }
1139 
1140 static bool g4x_compute_srwm(struct drm_device *dev,
1141 			     int plane,
1142 			     int latency_ns,
1143 			     const struct intel_watermark_params *display,
1144 			     const struct intel_watermark_params *cursor,
1145 			     int *display_wm, int *cursor_wm)
1146 {
1147 	struct drm_crtc *crtc;
1148 	int hdisplay, htotal, pixel_size, clock;
1149 	unsigned long line_time_us;
1150 	int line_count, line_size;
1151 	int small, large;
1152 	int entries;
1153 
1154 	if (!latency_ns) {
1155 		*display_wm = *cursor_wm = 0;
1156 		return false;
1157 	}
1158 
1159 	crtc = intel_get_crtc_for_plane(dev, plane);
1160 	hdisplay = crtc->mode.hdisplay;
1161 	htotal = crtc->mode.htotal;
1162 	clock = crtc->mode.clock;
1163 	pixel_size = crtc->fb->bits_per_pixel / 8;
1164 
1165 	line_time_us = (htotal * 1000) / clock;
1166 	line_count = (latency_ns / line_time_us + 1000) / 1000;
1167 	line_size = hdisplay * pixel_size;
1168 
1169 	/* Use the minimum of the small and large buffer method for primary */
1170 	small = ((clock * pixel_size / 1000) * latency_ns) / 1000;
1171 	large = line_count * line_size;
1172 
1173 	entries = howmany(min(small, large), display->cacheline_size);
1174 	*display_wm = entries + display->guard_size;
1175 
1176 	/* calculate the self-refresh watermark for display cursor */
1177 	entries = line_count * pixel_size * 64;
1178 	entries = howmany(entries, cursor->cacheline_size);
1179 	*cursor_wm = entries + cursor->guard_size;
1180 
1181 	return g4x_check_srwm(dev,
1182 			      *display_wm, *cursor_wm,
1183 			      display, cursor);
1184 }
1185 
1186 #define single_plane_enabled(mask) ((mask) != 0 && powerof2(mask))
1187 
1188 void g4x_update_wm(struct drm_device *dev)
1189 {
1190 	static const int sr_latency_ns = 12000;
1191 	struct drm_i915_private *dev_priv = dev->dev_private;
1192 	int planea_wm, planeb_wm, cursora_wm, cursorb_wm;
1193 	int plane_sr, cursor_sr;
1194 	unsigned int enabled = 0;
1195 
1196 	if (g4x_compute_wm0(dev, 0,
1197 			    &g4x_wm_info, latency_ns,
1198 			    &g4x_cursor_wm_info, latency_ns,
1199 			    &planea_wm, &cursora_wm))
1200 		enabled |= 1;
1201 
1202 	if (g4x_compute_wm0(dev, 1,
1203 			    &g4x_wm_info, latency_ns,
1204 			    &g4x_cursor_wm_info, latency_ns,
1205 			    &planeb_wm, &cursorb_wm))
1206 		enabled |= 2;
1207 
1208 	plane_sr = cursor_sr = 0;
1209 	if (single_plane_enabled(enabled) &&
1210 	    g4x_compute_srwm(dev, ffs(enabled) - 1,
1211 			     sr_latency_ns,
1212 			     &g4x_wm_info,
1213 			     &g4x_cursor_wm_info,
1214 			     &plane_sr, &cursor_sr))
1215 		I915_WRITE(FW_BLC_SELF, FW_BLC_SELF_EN);
1216 	else
1217 		I915_WRITE(FW_BLC_SELF,
1218 			   I915_READ(FW_BLC_SELF) & ~FW_BLC_SELF_EN);
1219 
1220 	DRM_DEBUG_KMS("Setting FIFO watermarks - A: plane=%d, cursor=%d, B: plane=%d, cursor=%d, SR: plane=%d, cursor=%d\n",
1221 		      planea_wm, cursora_wm,
1222 		      planeb_wm, cursorb_wm,
1223 		      plane_sr, cursor_sr);
1224 
1225 	I915_WRITE(DSPFW1,
1226 		   (plane_sr << DSPFW_SR_SHIFT) |
1227 		   (cursorb_wm << DSPFW_CURSORB_SHIFT) |
1228 		   (planeb_wm << DSPFW_PLANEB_SHIFT) |
1229 		   planea_wm);
1230 	I915_WRITE(DSPFW2,
1231 		   (I915_READ(DSPFW2) & DSPFW_CURSORA_MASK) |
1232 		   (cursora_wm << DSPFW_CURSORA_SHIFT));
1233 	/* HPLL off in SR has some issues on G4x... disable it */
1234 	I915_WRITE(DSPFW3,
1235 		   (I915_READ(DSPFW3) & ~DSPFW_HPLL_SR_EN) |
1236 		   (cursor_sr << DSPFW_CURSOR_SR_SHIFT));
1237 }
1238 
1239 void i965_update_wm(struct drm_device *dev)
1240 {
1241 	struct drm_i915_private *dev_priv = dev->dev_private;
1242 	struct drm_crtc *crtc;
1243 	int srwm = 1;
1244 	int cursor_sr = 16;
1245 
1246 	/* Calc sr entries for one plane configs */
1247 	crtc = single_enabled_crtc(dev);
1248 	if (crtc) {
1249 		/* self-refresh has much higher latency */
1250 		static const int sr_latency_ns = 12000;
1251 		int clock = crtc->mode.clock;
1252 		int htotal = crtc->mode.htotal;
1253 		int hdisplay = crtc->mode.hdisplay;
1254 		int pixel_size = crtc->fb->bits_per_pixel / 8;
1255 		unsigned long line_time_us;
1256 		int entries;
1257 
1258 		line_time_us = ((htotal * 1000) / clock);
1259 
1260 		/* Use ns/us then divide to preserve precision */
1261 		entries = (((sr_latency_ns / line_time_us) + 1000) / 1000) *
1262 			pixel_size * hdisplay;
1263 		entries = howmany(entries, I915_FIFO_LINE_SIZE);
1264 		srwm = I965_FIFO_SIZE - entries;
1265 		if (srwm < 0)
1266 			srwm = 1;
1267 		srwm &= 0x1ff;
1268 		DRM_DEBUG_KMS("self-refresh entries: %d, wm: %d\n",
1269 			      entries, srwm);
1270 
1271 		entries = (((sr_latency_ns / line_time_us) + 1000) / 1000) *
1272 			pixel_size * 64;
1273 		entries = howmany(entries, i965_cursor_wm_info.cacheline_size);
1274 		cursor_sr = i965_cursor_wm_info.fifo_size -
1275 			(entries + i965_cursor_wm_info.guard_size);
1276 
1277 		if (cursor_sr > i965_cursor_wm_info.max_wm)
1278 			cursor_sr = i965_cursor_wm_info.max_wm;
1279 
1280 		DRM_DEBUG_KMS("self-refresh watermark: display plane %d "
1281 			      "cursor %d\n", srwm, cursor_sr);
1282 
1283 		if (IS_CRESTLINE(dev))
1284 			I915_WRITE(FW_BLC_SELF, FW_BLC_SELF_EN);
1285 	} else {
1286 		/* Turn off self refresh if both pipes are enabled */
1287 		if (IS_CRESTLINE(dev))
1288 			I915_WRITE(FW_BLC_SELF, I915_READ(FW_BLC_SELF)
1289 				   & ~FW_BLC_SELF_EN);
1290 	}
1291 
1292 	DRM_DEBUG_KMS("Setting FIFO watermarks - A: 8, B: 8, C: 8, SR %d\n",
1293 		      srwm);
1294 
1295 	/* 965 has limitations... */
1296 	I915_WRITE(DSPFW1, (srwm << DSPFW_SR_SHIFT) |
1297 		   (8 << 16) | (8 << 8) | (8 << 0));
1298 	I915_WRITE(DSPFW2, (8 << 8) | (8 << 0));
1299 	/* update cursor SR watermark */
1300 	I915_WRITE(DSPFW3, (cursor_sr << DSPFW_CURSOR_SR_SHIFT));
1301 }
1302 
1303 void i9xx_update_wm(struct drm_device *dev)
1304 {
1305 	struct drm_i915_private *dev_priv = dev->dev_private;
1306 	const struct intel_watermark_params *wm_info;
1307 	uint32_t fwater_lo;
1308 	uint32_t fwater_hi;
1309 	int cwm, srwm = 1;
1310 	int fifo_size;
1311 	int planea_wm, planeb_wm;
1312 	struct drm_crtc *crtc, *enabled = NULL;
1313 
1314 	if (IS_I945GM(dev))
1315 		wm_info = &i945_wm_info;
1316 	else if (!IS_GEN2(dev))
1317 		wm_info = &i915_wm_info;
1318 	else
1319 		wm_info = &i855_wm_info;
1320 
1321 	fifo_size = dev_priv->display.get_fifo_size(dev, 0);
1322 	crtc = intel_get_crtc_for_plane(dev, 0);
1323 	if (crtc->enabled && crtc->fb) {
1324 		planea_wm = intel_calculate_wm(crtc->mode.clock,
1325 					       wm_info, fifo_size,
1326 					       crtc->fb->bits_per_pixel / 8,
1327 					       latency_ns);
1328 		enabled = crtc;
1329 	} else
1330 		planea_wm = fifo_size - wm_info->guard_size;
1331 
1332 	fifo_size = dev_priv->display.get_fifo_size(dev, 1);
1333 	crtc = intel_get_crtc_for_plane(dev, 1);
1334 	if (crtc->enabled && crtc->fb) {
1335 		planeb_wm = intel_calculate_wm(crtc->mode.clock,
1336 					       wm_info, fifo_size,
1337 					       crtc->fb->bits_per_pixel / 8,
1338 					       latency_ns);
1339 		if (enabled == NULL)
1340 			enabled = crtc;
1341 		else
1342 			enabled = NULL;
1343 	} else
1344 		planeb_wm = fifo_size - wm_info->guard_size;
1345 
1346 	DRM_DEBUG_KMS("FIFO watermarks - A: %d, B: %d\n", planea_wm, planeb_wm);
1347 
1348 	/*
1349 	 * Overlay gets an aggressive default since video jitter is bad.
1350 	 */
1351 	cwm = 2;
1352 
1353 	/* Play safe and disable self-refresh before adjusting watermarks. */
1354 	if (IS_I945G(dev) || IS_I945GM(dev))
1355 		I915_WRITE(FW_BLC_SELF, FW_BLC_SELF_EN_MASK | 0);
1356 	else if (IS_I915GM(dev))
1357 		I915_WRITE(INSTPM, I915_READ(INSTPM) & ~INSTPM_SELF_EN);
1358 
1359 	/* Calc sr entries for one plane configs */
1360 	if (HAS_FW_BLC(dev) && enabled) {
1361 		/* self-refresh has much higher latency */
1362 		static const int sr_latency_ns = 6000;
1363 		int clock = enabled->mode.clock;
1364 		int htotal = enabled->mode.htotal;
1365 		int hdisplay = enabled->mode.hdisplay;
1366 		int pixel_size = enabled->fb->bits_per_pixel / 8;
1367 		unsigned long line_time_us;
1368 		int entries;
1369 
1370 		line_time_us = (htotal * 1000) / clock;
1371 
1372 		/* Use ns/us then divide to preserve precision */
1373 		entries = (((sr_latency_ns / line_time_us) + 1000) / 1000) *
1374 			pixel_size * hdisplay;
1375 		entries = howmany(entries, wm_info->cacheline_size);
1376 		DRM_DEBUG_KMS("self-refresh entries: %d\n", entries);
1377 		srwm = wm_info->fifo_size - entries;
1378 		if (srwm < 0)
1379 			srwm = 1;
1380 
1381 		if (IS_I945G(dev) || IS_I945GM(dev))
1382 			I915_WRITE(FW_BLC_SELF,
1383 				   FW_BLC_SELF_FIFO_MASK | (srwm & 0xff));
1384 		else if (IS_I915GM(dev))
1385 			I915_WRITE(FW_BLC_SELF, srwm & 0x3f);
1386 	}
1387 
1388 	DRM_DEBUG_KMS("Setting FIFO watermarks - A: %d, B: %d, C: %d, SR %d\n",
1389 		      planea_wm, planeb_wm, cwm, srwm);
1390 
1391 	fwater_lo = ((planeb_wm & 0x3f) << 16) | (planea_wm & 0x3f);
1392 	fwater_hi = (cwm & 0x1f);
1393 
1394 	/* Set request length to 8 cachelines per fetch */
1395 	fwater_lo = fwater_lo | (1 << 24) | (1 << 8);
1396 	fwater_hi = fwater_hi | (1 << 8);
1397 
1398 	I915_WRITE(FW_BLC, fwater_lo);
1399 	I915_WRITE(FW_BLC2, fwater_hi);
1400 
1401 	if (HAS_FW_BLC(dev)) {
1402 		if (enabled) {
1403 			if (IS_I945G(dev) || IS_I945GM(dev))
1404 				I915_WRITE(FW_BLC_SELF,
1405 					   FW_BLC_SELF_EN_MASK | FW_BLC_SELF_EN);
1406 			else if (IS_I915GM(dev))
1407 				I915_WRITE(INSTPM, I915_READ(INSTPM) | INSTPM_SELF_EN);
1408 			DRM_DEBUG_KMS("memory self refresh enabled\n");
1409 		} else
1410 			DRM_DEBUG_KMS("memory self refresh disabled\n");
1411 	}
1412 }
1413 
1414 void i830_update_wm(struct drm_device *dev)
1415 {
1416 	struct drm_i915_private *dev_priv = dev->dev_private;
1417 	struct drm_crtc *crtc;
1418 	uint32_t fwater_lo;
1419 	int planea_wm;
1420 
1421 	crtc = single_enabled_crtc(dev);
1422 	if (crtc == NULL)
1423 		return;
1424 
1425 	planea_wm = intel_calculate_wm(crtc->mode.clock, &i830_wm_info,
1426 				       dev_priv->display.get_fifo_size(dev, 0),
1427 				       crtc->fb->bits_per_pixel / 8,
1428 				       latency_ns);
1429 	fwater_lo = I915_READ(FW_BLC) & ~0xfff;
1430 	fwater_lo |= (3<<8) | planea_wm;
1431 
1432 	DRM_DEBUG_KMS("Setting FIFO watermarks - A: %d\n", planea_wm);
1433 
1434 	I915_WRITE(FW_BLC, fwater_lo);
1435 }
1436 
1437 #define ILK_LP0_PLANE_LATENCY		700
1438 #define ILK_LP0_CURSOR_LATENCY		1300
1439 
1440 /*
1441  * Check the wm result.
1442  *
1443  * If any calculated watermark values is larger than the maximum value that
1444  * can be programmed into the associated watermark register, that watermark
1445  * must be disabled.
1446  */
1447 static bool ironlake_check_srwm(struct drm_device *dev, int level,
1448 				int fbc_wm, int display_wm, int cursor_wm,
1449 				const struct intel_watermark_params *display,
1450 				const struct intel_watermark_params *cursor)
1451 {
1452 	struct drm_i915_private *dev_priv = dev->dev_private;
1453 
1454 	DRM_DEBUG_KMS("watermark %d: display plane %d, fbc lines %d,"
1455 		      " cursor %d\n", level, display_wm, fbc_wm, cursor_wm);
1456 
1457 	if (fbc_wm > SNB_FBC_MAX_SRWM) {
1458 		DRM_DEBUG_KMS("fbc watermark(%d) is too large(%d), disabling wm%d+\n",
1459 			      fbc_wm, SNB_FBC_MAX_SRWM, level);
1460 
1461 		/* fbc has it's own way to disable FBC WM */
1462 		I915_WRITE(DISP_ARB_CTL,
1463 			   I915_READ(DISP_ARB_CTL) | DISP_FBC_WM_DIS);
1464 		return false;
1465 	}
1466 
1467 	if (display_wm > display->max_wm) {
1468 		DRM_DEBUG_KMS("display watermark(%d) is too large(%d), disabling wm%d+\n",
1469 			      display_wm, SNB_DISPLAY_MAX_SRWM, level);
1470 		return false;
1471 	}
1472 
1473 	if (cursor_wm > cursor->max_wm) {
1474 		DRM_DEBUG_KMS("cursor watermark(%d) is too large(%d), disabling wm%d+\n",
1475 			      cursor_wm, SNB_CURSOR_MAX_SRWM, level);
1476 		return false;
1477 	}
1478 
1479 	if (!(fbc_wm || display_wm || cursor_wm)) {
1480 		DRM_DEBUG_KMS("latency %d is 0, disabling wm%d+\n", level, level);
1481 		return false;
1482 	}
1483 
1484 	return true;
1485 }
1486 
1487 /*
1488  * Compute watermark values of WM[1-3],
1489  */
1490 static bool ironlake_compute_srwm(struct drm_device *dev, int level, int plane,
1491 				  int latency_ns,
1492 				  const struct intel_watermark_params *display,
1493 				  const struct intel_watermark_params *cursor,
1494 				  int *fbc_wm, int *display_wm, int *cursor_wm)
1495 {
1496 	struct drm_crtc *crtc;
1497 	unsigned long line_time_us;
1498 	int hdisplay, htotal, pixel_size, clock;
1499 	int line_count, line_size;
1500 	int small, large;
1501 	int entries;
1502 
1503 	if (!latency_ns) {
1504 		*fbc_wm = *display_wm = *cursor_wm = 0;
1505 		return false;
1506 	}
1507 
1508 	crtc = intel_get_crtc_for_plane(dev, plane);
1509 	hdisplay = crtc->mode.hdisplay;
1510 	htotal = crtc->mode.htotal;
1511 	clock = crtc->mode.clock;
1512 	pixel_size = crtc->fb->bits_per_pixel / 8;
1513 
1514 	line_time_us = (htotal * 1000) / clock;
1515 	line_count = (latency_ns / line_time_us + 1000) / 1000;
1516 	line_size = hdisplay * pixel_size;
1517 
1518 	/* Use the minimum of the small and large buffer method for primary */
1519 	small = ((clock * pixel_size / 1000) * latency_ns) / 1000;
1520 	large = line_count * line_size;
1521 
1522 	entries = howmany(min(small, large), display->cacheline_size);
1523 	*display_wm = entries + display->guard_size;
1524 
1525 	/*
1526 	 * Spec says:
1527 	 * FBC WM = ((Final Primary WM * 64) / number of bytes per line) + 2
1528 	 */
1529 	*fbc_wm = howmany(*display_wm * 64, line_size) + 2;
1530 
1531 	/* calculate the self-refresh watermark for display cursor */
1532 	entries = line_count * pixel_size * 64;
1533 	entries = howmany(entries, cursor->cacheline_size);
1534 	*cursor_wm = entries + cursor->guard_size;
1535 
1536 	return ironlake_check_srwm(dev, level,
1537 				   *fbc_wm, *display_wm, *cursor_wm,
1538 				   display, cursor);
1539 }
1540 
1541 void ironlake_update_wm(struct drm_device *dev)
1542 {
1543 	struct drm_i915_private *dev_priv = dev->dev_private;
1544 	int fbc_wm, plane_wm, cursor_wm;
1545 	unsigned int enabled;
1546 
1547 	enabled = 0;
1548 	if (g4x_compute_wm0(dev, 0,
1549 			    &ironlake_display_wm_info,
1550 			    ILK_LP0_PLANE_LATENCY,
1551 			    &ironlake_cursor_wm_info,
1552 			    ILK_LP0_CURSOR_LATENCY,
1553 			    &plane_wm, &cursor_wm)) {
1554 		I915_WRITE(WM0_PIPEA_ILK,
1555 			   (plane_wm << WM0_PIPE_PLANE_SHIFT) | cursor_wm);
1556 		DRM_DEBUG_KMS("FIFO watermarks For pipe A -"
1557 			      " plane %d, " "cursor: %d\n",
1558 			      plane_wm, cursor_wm);
1559 		enabled |= 1;
1560 	}
1561 
1562 	if (g4x_compute_wm0(dev, 1,
1563 			    &ironlake_display_wm_info,
1564 			    ILK_LP0_PLANE_LATENCY,
1565 			    &ironlake_cursor_wm_info,
1566 			    ILK_LP0_CURSOR_LATENCY,
1567 			    &plane_wm, &cursor_wm)) {
1568 		I915_WRITE(WM0_PIPEB_ILK,
1569 			   (plane_wm << WM0_PIPE_PLANE_SHIFT) | cursor_wm);
1570 		DRM_DEBUG_KMS("FIFO watermarks For pipe B -"
1571 			      " plane %d, cursor: %d\n",
1572 			      plane_wm, cursor_wm);
1573 		enabled |= 2;
1574 	}
1575 
1576 	/*
1577 	 * Calculate and update the self-refresh watermark only when one
1578 	 * display plane is used.
1579 	 */
1580 	I915_WRITE(WM3_LP_ILK, 0);
1581 	I915_WRITE(WM2_LP_ILK, 0);
1582 	I915_WRITE(WM1_LP_ILK, 0);
1583 
1584 	if (!single_plane_enabled(enabled))
1585 		return;
1586 	enabled = ffs(enabled) - 1;
1587 
1588 	/* WM1 */
1589 	if (!ironlake_compute_srwm(dev, 1, enabled,
1590 				   ILK_READ_WM1_LATENCY() * 500,
1591 				   &ironlake_display_srwm_info,
1592 				   &ironlake_cursor_srwm_info,
1593 				   &fbc_wm, &plane_wm, &cursor_wm))
1594 		return;
1595 
1596 	I915_WRITE(WM1_LP_ILK,
1597 		   WM1_LP_SR_EN |
1598 		   (ILK_READ_WM1_LATENCY() << WM1_LP_LATENCY_SHIFT) |
1599 		   (fbc_wm << WM1_LP_FBC_SHIFT) |
1600 		   (plane_wm << WM1_LP_SR_SHIFT) |
1601 		   cursor_wm);
1602 
1603 	/* WM2 */
1604 	if (!ironlake_compute_srwm(dev, 2, enabled,
1605 				   ILK_READ_WM2_LATENCY() * 500,
1606 				   &ironlake_display_srwm_info,
1607 				   &ironlake_cursor_srwm_info,
1608 				   &fbc_wm, &plane_wm, &cursor_wm))
1609 		return;
1610 
1611 	I915_WRITE(WM2_LP_ILK,
1612 		   WM2_LP_EN |
1613 		   (ILK_READ_WM2_LATENCY() << WM1_LP_LATENCY_SHIFT) |
1614 		   (fbc_wm << WM1_LP_FBC_SHIFT) |
1615 		   (plane_wm << WM1_LP_SR_SHIFT) |
1616 		   cursor_wm);
1617 
1618 	/*
1619 	 * WM3 is unsupported on ILK, probably because we don't have latency
1620 	 * data for that power state
1621 	 */
1622 }
1623 
1624 void sandybridge_update_wm(struct drm_device *dev)
1625 {
1626 	struct drm_i915_private *dev_priv = dev->dev_private;
1627 	int latency = SNB_READ_WM0_LATENCY() * 100;	/* In unit 0.1us */
1628 	u32 val;
1629 	int fbc_wm, plane_wm, cursor_wm;
1630 	unsigned int enabled;
1631 
1632 	enabled = 0;
1633 	if (g4x_compute_wm0(dev, 0,
1634 			    &sandybridge_display_wm_info, latency,
1635 			    &sandybridge_cursor_wm_info, latency,
1636 			    &plane_wm, &cursor_wm)) {
1637 		val = I915_READ(WM0_PIPEA_ILK);
1638 		val &= ~(WM0_PIPE_PLANE_MASK | WM0_PIPE_CURSOR_MASK);
1639 		I915_WRITE(WM0_PIPEA_ILK, val |
1640 			   ((plane_wm << WM0_PIPE_PLANE_SHIFT) | cursor_wm));
1641 		DRM_DEBUG_KMS("FIFO watermarks For pipe A -"
1642 			      " plane %d, " "cursor: %d\n",
1643 			      plane_wm, cursor_wm);
1644 		enabled |= 1;
1645 	}
1646 
1647 	if (g4x_compute_wm0(dev, 1,
1648 			    &sandybridge_display_wm_info, latency,
1649 			    &sandybridge_cursor_wm_info, latency,
1650 			    &plane_wm, &cursor_wm)) {
1651 		val = I915_READ(WM0_PIPEB_ILK);
1652 		val &= ~(WM0_PIPE_PLANE_MASK | WM0_PIPE_CURSOR_MASK);
1653 		I915_WRITE(WM0_PIPEB_ILK, val |
1654 			   ((plane_wm << WM0_PIPE_PLANE_SHIFT) | cursor_wm));
1655 		DRM_DEBUG_KMS("FIFO watermarks For pipe B -"
1656 			      " plane %d, cursor: %d\n",
1657 			      plane_wm, cursor_wm);
1658 		enabled |= 2;
1659 	}
1660 
1661 	/* IVB has 3 pipes */
1662 	if (IS_IVYBRIDGE(dev) &&
1663 	    g4x_compute_wm0(dev, 2,
1664 			    &sandybridge_display_wm_info, latency,
1665 			    &sandybridge_cursor_wm_info, latency,
1666 			    &plane_wm, &cursor_wm)) {
1667 		val = I915_READ(WM0_PIPEC_IVB);
1668 		val &= ~(WM0_PIPE_PLANE_MASK | WM0_PIPE_CURSOR_MASK);
1669 		I915_WRITE(WM0_PIPEC_IVB, val |
1670 			   ((plane_wm << WM0_PIPE_PLANE_SHIFT) | cursor_wm));
1671 		DRM_DEBUG_KMS("FIFO watermarks For pipe C -"
1672 			      " plane %d, cursor: %d\n",
1673 			      plane_wm, cursor_wm);
1674 		enabled |= 3;
1675 	}
1676 
1677 	/*
1678 	 * Calculate and update the self-refresh watermark only when one
1679 	 * display plane is used.
1680 	 *
1681 	 * SNB support 3 levels of watermark.
1682 	 *
1683 	 * WM1/WM2/WM2 watermarks have to be enabled in the ascending order,
1684 	 * and disabled in the descending order
1685 	 *
1686 	 */
1687 	I915_WRITE(WM3_LP_ILK, 0);
1688 	I915_WRITE(WM2_LP_ILK, 0);
1689 	I915_WRITE(WM1_LP_ILK, 0);
1690 
1691 	if (!single_plane_enabled(enabled) ||
1692 	    dev_priv->sprite_scaling_enabled)
1693 		return;
1694 	enabled = ffs(enabled) - 1;
1695 
1696 	/* WM1 */
1697 	if (!ironlake_compute_srwm(dev, 1, enabled,
1698 				   SNB_READ_WM1_LATENCY() * 500,
1699 				   &sandybridge_display_srwm_info,
1700 				   &sandybridge_cursor_srwm_info,
1701 				   &fbc_wm, &plane_wm, &cursor_wm))
1702 		return;
1703 
1704 	I915_WRITE(WM1_LP_ILK,
1705 		   WM1_LP_SR_EN |
1706 		   (SNB_READ_WM1_LATENCY() << WM1_LP_LATENCY_SHIFT) |
1707 		   (fbc_wm << WM1_LP_FBC_SHIFT) |
1708 		   (plane_wm << WM1_LP_SR_SHIFT) |
1709 		   cursor_wm);
1710 
1711 	/* WM2 */
1712 	if (!ironlake_compute_srwm(dev, 2, enabled,
1713 				   SNB_READ_WM2_LATENCY() * 500,
1714 				   &sandybridge_display_srwm_info,
1715 				   &sandybridge_cursor_srwm_info,
1716 				   &fbc_wm, &plane_wm, &cursor_wm))
1717 		return;
1718 
1719 	I915_WRITE(WM2_LP_ILK,
1720 		   WM2_LP_EN |
1721 		   (SNB_READ_WM2_LATENCY() << WM1_LP_LATENCY_SHIFT) |
1722 		   (fbc_wm << WM1_LP_FBC_SHIFT) |
1723 		   (plane_wm << WM1_LP_SR_SHIFT) |
1724 		   cursor_wm);
1725 
1726 	/* WM3 */
1727 	if (!ironlake_compute_srwm(dev, 3, enabled,
1728 				   SNB_READ_WM3_LATENCY() * 500,
1729 				   &sandybridge_display_srwm_info,
1730 				   &sandybridge_cursor_srwm_info,
1731 				   &fbc_wm, &plane_wm, &cursor_wm))
1732 		return;
1733 
1734 	I915_WRITE(WM3_LP_ILK,
1735 		   WM3_LP_EN |
1736 		   (SNB_READ_WM3_LATENCY() << WM1_LP_LATENCY_SHIFT) |
1737 		   (fbc_wm << WM1_LP_FBC_SHIFT) |
1738 		   (plane_wm << WM1_LP_SR_SHIFT) |
1739 		   cursor_wm);
1740 }
1741 
1742 static bool
1743 sandybridge_compute_sprite_wm(struct drm_device *dev, int plane,
1744 			      uint32_t sprite_width, int pixel_size,
1745 			      const struct intel_watermark_params *display,
1746 			      int display_latency_ns, int *sprite_wm)
1747 {
1748 	struct drm_crtc *crtc;
1749 	int clock;
1750 	int entries, tlb_miss;
1751 
1752 	crtc = intel_get_crtc_for_plane(dev, plane);
1753 	if (crtc->fb == NULL || !crtc->enabled) {
1754 		*sprite_wm = display->guard_size;
1755 		return false;
1756 	}
1757 
1758 	clock = crtc->mode.clock;
1759 
1760 	/* Use the small buffer method to calculate the sprite watermark */
1761 	entries = ((clock * pixel_size / 1000) * display_latency_ns) / 1000;
1762 	tlb_miss = display->fifo_size*display->cacheline_size -
1763 		sprite_width * 8;
1764 	if (tlb_miss > 0)
1765 		entries += tlb_miss;
1766 	entries = howmany(entries, display->cacheline_size);
1767 	*sprite_wm = entries + display->guard_size;
1768 	if (*sprite_wm > (int)display->max_wm)
1769 		*sprite_wm = display->max_wm;
1770 
1771 	return true;
1772 }
1773 
1774 static bool
1775 sandybridge_compute_sprite_srwm(struct drm_device *dev, int plane,
1776 				uint32_t sprite_width, int pixel_size,
1777 				const struct intel_watermark_params *display,
1778 				int latency_ns, int *sprite_wm)
1779 {
1780 	struct drm_crtc *crtc;
1781 	unsigned long line_time_us;
1782 	int clock;
1783 	int line_count, line_size;
1784 	int small, large;
1785 	int entries;
1786 
1787 	if (!latency_ns) {
1788 		*sprite_wm = 0;
1789 		return false;
1790 	}
1791 
1792 	crtc = intel_get_crtc_for_plane(dev, plane);
1793 	clock = crtc->mode.clock;
1794 	if (!clock) {
1795 		*sprite_wm = 0;
1796 		return false;
1797 	}
1798 
1799 	line_time_us = (sprite_width * 1000) / clock;
1800 	if (!line_time_us) {
1801 		*sprite_wm = 0;
1802 		return false;
1803 	}
1804 
1805 	line_count = (latency_ns / line_time_us + 1000) / 1000;
1806 	line_size = sprite_width * pixel_size;
1807 
1808 	/* Use the minimum of the small and large buffer method for primary */
1809 	small = ((clock * pixel_size / 1000) * latency_ns) / 1000;
1810 	large = line_count * line_size;
1811 
1812 	entries = howmany(min(small, large), display->cacheline_size);
1813 	*sprite_wm = entries + display->guard_size;
1814 
1815 	return *sprite_wm > 0x3ff ? false : true;
1816 }
1817 
1818 void sandybridge_update_sprite_wm(struct drm_device *dev, int pipe,
1819 					 uint32_t sprite_width, int pixel_size)
1820 {
1821 	struct drm_i915_private *dev_priv = dev->dev_private;
1822 	int latency = SNB_READ_WM0_LATENCY() * 100;	/* In unit 0.1us */
1823 	u32 val;
1824 	int sprite_wm, reg;
1825 	int ret;
1826 
1827 	switch (pipe) {
1828 	case 0:
1829 		reg = WM0_PIPEA_ILK;
1830 		break;
1831 	case 1:
1832 		reg = WM0_PIPEB_ILK;
1833 		break;
1834 	case 2:
1835 		reg = WM0_PIPEC_IVB;
1836 		break;
1837 	default:
1838 		return; /* bad pipe */
1839 	}
1840 
1841 	ret = sandybridge_compute_sprite_wm(dev, pipe, sprite_width, pixel_size,
1842 					    &sandybridge_display_wm_info,
1843 					    latency, &sprite_wm);
1844 	if (!ret) {
1845 		DRM_DEBUG_KMS("failed to compute sprite wm for pipe %d\n",
1846 			      pipe);
1847 		return;
1848 	}
1849 
1850 	val = I915_READ(reg);
1851 	val &= ~WM0_PIPE_SPRITE_MASK;
1852 	I915_WRITE(reg, val | (sprite_wm << WM0_PIPE_SPRITE_SHIFT));
1853 	DRM_DEBUG_KMS("sprite watermarks For pipe %d - %d\n", pipe, sprite_wm);
1854 
1855 
1856 	ret = sandybridge_compute_sprite_srwm(dev, pipe, sprite_width,
1857 					      pixel_size,
1858 					      &sandybridge_display_srwm_info,
1859 					      SNB_READ_WM1_LATENCY() * 500,
1860 					      &sprite_wm);
1861 	if (!ret) {
1862 		DRM_DEBUG_KMS("failed to compute sprite lp1 wm on pipe %d\n",
1863 			      pipe);
1864 		return;
1865 	}
1866 	I915_WRITE(WM1S_LP_ILK, sprite_wm);
1867 
1868 	/* Only IVB has two more LP watermarks for sprite */
1869 	if (!IS_IVYBRIDGE(dev))
1870 		return;
1871 
1872 	ret = sandybridge_compute_sprite_srwm(dev, pipe, sprite_width,
1873 					      pixel_size,
1874 					      &sandybridge_display_srwm_info,
1875 					      SNB_READ_WM2_LATENCY() * 500,
1876 					      &sprite_wm);
1877 	if (!ret) {
1878 		DRM_DEBUG_KMS("failed to compute sprite lp2 wm on pipe %d\n",
1879 			      pipe);
1880 		return;
1881 	}
1882 	I915_WRITE(WM2S_LP_IVB, sprite_wm);
1883 
1884 	ret = sandybridge_compute_sprite_srwm(dev, pipe, sprite_width,
1885 					      pixel_size,
1886 					      &sandybridge_display_srwm_info,
1887 					      SNB_READ_WM3_LATENCY() * 500,
1888 					      &sprite_wm);
1889 	if (!ret) {
1890 		DRM_DEBUG_KMS("failed to compute sprite lp3 wm on pipe %d\n",
1891 			      pipe);
1892 		return;
1893 	}
1894 	I915_WRITE(WM3S_LP_IVB, sprite_wm);
1895 }
1896 
1897 /**
1898  * intel_update_watermarks - update FIFO watermark values based on current modes
1899  *
1900  * Calculate watermark values for the various WM regs based on current mode
1901  * and plane configuration.
1902  *
1903  * There are several cases to deal with here:
1904  *   - normal (i.e. non-self-refresh)
1905  *   - self-refresh (SR) mode
1906  *   - lines are large relative to FIFO size (buffer can hold up to 2)
1907  *   - lines are small relative to FIFO size (buffer can hold more than 2
1908  *     lines), so need to account for TLB latency
1909  *
1910  *   The normal calculation is:
1911  *     watermark = dotclock * bytes per pixel * latency
1912  *   where latency is platform & configuration dependent (we assume pessimal
1913  *   values here).
1914  *
1915  *   The SR calculation is:
1916  *     watermark = (trunc(latency/line time)+1) * surface width *
1917  *       bytes per pixel
1918  *   where
1919  *     line time = htotal / dotclock
1920  *     surface width = hdisplay for normal plane and 64 for cursor
1921  *   and latency is assumed to be high, as above.
1922  *
1923  * The final value programmed to the register should always be rounded up,
1924  * and include an extra 2 entries to account for clock crossings.
1925  *
1926  * We don't use the sprite, so we can ignore that.  And on Crestline we have
1927  * to set the non-SR watermarks to 8.
1928  */
1929 void intel_update_watermarks(struct drm_device *dev)
1930 {
1931 	struct drm_i915_private *dev_priv = dev->dev_private;
1932 
1933 	if (dev_priv->display.update_wm)
1934 		dev_priv->display.update_wm(dev);
1935 }
1936 
1937 void intel_update_sprite_watermarks(struct drm_device *dev, int pipe,
1938 				    uint32_t sprite_width, int pixel_size)
1939 {
1940 	struct drm_i915_private *dev_priv = dev->dev_private;
1941 
1942 	if (dev_priv->display.update_sprite_wm)
1943 		dev_priv->display.update_sprite_wm(dev, pipe, sprite_width,
1944 						   pixel_size);
1945 }
1946 
1947 static struct drm_i915_gem_object *
1948 intel_alloc_context_page(struct drm_device *dev)
1949 {
1950 	struct drm_i915_gem_object *ctx;
1951 	int ret;
1952 
1953 	DRM_LOCK_ASSERT(dev);
1954 
1955 	ctx = i915_gem_alloc_object(dev, 4096);
1956 	if (!ctx) {
1957 		DRM_DEBUG("failed to alloc power context, RC6 disabled\n");
1958 		return NULL;
1959 	}
1960 
1961 	ret = i915_gem_object_pin(ctx, 4096, true);
1962 	if (ret) {
1963 		DRM_ERROR("failed to pin power context: %d\n", ret);
1964 		goto err_unref;
1965 	}
1966 
1967 	ret = i915_gem_object_set_to_gtt_domain(ctx, 1);
1968 	if (ret) {
1969 		DRM_ERROR("failed to set-domain on power context: %d\n", ret);
1970 		goto err_unpin;
1971 	}
1972 
1973 	return ctx;
1974 
1975 err_unpin:
1976 	i915_gem_object_unpin(ctx);
1977 err_unref:
1978 	drm_gem_object_unreference(&ctx->base);
1979 	DRM_UNLOCK(dev);
1980 	return NULL;
1981 }
1982 
1983 /**
1984  * Lock protecting IPS related data structures
1985  */
1986 struct lock mchdev_lock;
1987 LOCK_SYSINIT(mchdev, &mchdev_lock, "mchdev", LK_CANRECURSE);
1988 
1989 /* Global for IPS driver to get at the current i915 device. Protected by
1990  * mchdev_lock. */
1991 struct drm_i915_private *i915_mch_dev;
1992 
1993 bool ironlake_set_drps(struct drm_device *dev, u8 val)
1994 {
1995 	struct drm_i915_private *dev_priv = dev->dev_private;
1996 	u16 rgvswctl;
1997 
1998 	rgvswctl = I915_READ16(MEMSWCTL);
1999 	if (rgvswctl & MEMCTL_CMD_STS) {
2000 		DRM_DEBUG("gpu busy, RCS change rejected\n");
2001 		return false; /* still busy with another command */
2002 	}
2003 
2004 	rgvswctl = (MEMCTL_CMD_CHFREQ << MEMCTL_CMD_SHIFT) |
2005 		(val << MEMCTL_FREQ_SHIFT) | MEMCTL_SFCAVM;
2006 	I915_WRITE16(MEMSWCTL, rgvswctl);
2007 	POSTING_READ16(MEMSWCTL);
2008 
2009 	rgvswctl |= MEMCTL_CMD_STS;
2010 	I915_WRITE16(MEMSWCTL, rgvswctl);
2011 
2012 	return true;
2013 }
2014 
2015 void ironlake_enable_drps(struct drm_device *dev)
2016 {
2017 	struct drm_i915_private *dev_priv = dev->dev_private;
2018 	u32 rgvmodectl = I915_READ(MEMMODECTL);
2019 	u8 fmax, fmin, fstart, vstart;
2020 
2021 	/* Enable temp reporting */
2022 	I915_WRITE16(PMMISC, I915_READ(PMMISC) | MCPPCE_EN);
2023 	I915_WRITE16(TSC1, I915_READ(TSC1) | TSE);
2024 
2025 	/* 100ms RC evaluation intervals */
2026 	I915_WRITE(RCUPEI, 100000);
2027 	I915_WRITE(RCDNEI, 100000);
2028 
2029 	/* Set max/min thresholds to 90ms and 80ms respectively */
2030 	I915_WRITE(RCBMAXAVG, 90000);
2031 	I915_WRITE(RCBMINAVG, 80000);
2032 
2033 	I915_WRITE(MEMIHYST, 1);
2034 
2035 	/* Set up min, max, and cur for interrupt handling */
2036 	fmax = (rgvmodectl & MEMMODE_FMAX_MASK) >> MEMMODE_FMAX_SHIFT;
2037 	fmin = (rgvmodectl & MEMMODE_FMIN_MASK);
2038 	fstart = (rgvmodectl & MEMMODE_FSTART_MASK) >>
2039 		MEMMODE_FSTART_SHIFT;
2040 
2041 	vstart = (I915_READ(PXVFREQ_BASE + (fstart * 4)) & PXVFREQ_PX_MASK) >>
2042 		PXVFREQ_PX_SHIFT;
2043 
2044 	dev_priv->fmax = fmax; /* IPS callback will increase this */
2045 	dev_priv->fstart = fstart;
2046 
2047 	dev_priv->rps.max_delay = fstart;
2048 	dev_priv->rps.min_delay = fmin;
2049 	dev_priv->rps.cur_delay = fstart;
2050 
2051 	DRM_DEBUG("fmax: %d, fmin: %d, fstart: %d\n",
2052 			 fmax, fmin, fstart);
2053 
2054 	I915_WRITE(MEMINTREN, MEMINT_CX_SUPR_EN | MEMINT_EVAL_CHG_EN);
2055 
2056 	/*
2057 	 * Interrupts will be enabled in ironlake_irq_postinstall
2058 	 */
2059 
2060 	I915_WRITE(VIDSTART, vstart);
2061 	POSTING_READ(VIDSTART);
2062 
2063 	rgvmodectl |= MEMMODE_SWMODE_EN;
2064 	I915_WRITE(MEMMODECTL, rgvmodectl);
2065 
2066 	if (_intel_wait_for(dev,
2067 	    (I915_READ(MEMSWCTL) & MEMCTL_CMD_STS) == 0, 10,
2068 	    1, "915per"))
2069 		DRM_ERROR("stuck trying to change perf mode\n");
2070 	DELAY(1000);
2071 
2072 	ironlake_set_drps(dev, fstart);
2073 
2074 	dev_priv->last_count1 = I915_READ(0x112e4) + I915_READ(0x112e8) +
2075 		I915_READ(0x112e0);
2076 	dev_priv->last_time1 = jiffies_to_msecs(jiffies);
2077 	dev_priv->last_count2 = I915_READ(0x112f4);
2078 	nanotime(&dev_priv->last_time2);
2079 }
2080 
2081 void ironlake_disable_drps(struct drm_device *dev)
2082 {
2083 	struct drm_i915_private *dev_priv = dev->dev_private;
2084 	u16 rgvswctl = I915_READ16(MEMSWCTL);
2085 
2086 	/* Ack interrupts, disable EFC interrupt */
2087 	I915_WRITE(MEMINTREN, I915_READ(MEMINTREN) & ~MEMINT_EVAL_CHG_EN);
2088 	I915_WRITE(MEMINTRSTS, MEMINT_EVAL_CHG);
2089 	I915_WRITE(DEIER, I915_READ(DEIER) & ~DE_PCU_EVENT);
2090 	I915_WRITE(DEIIR, DE_PCU_EVENT);
2091 	I915_WRITE(DEIMR, I915_READ(DEIMR) | DE_PCU_EVENT);
2092 
2093 	/* Go back to the starting frequency */
2094 	ironlake_set_drps(dev, dev_priv->fstart);
2095 	DELAY(1000);
2096 	rgvswctl |= MEMCTL_CMD_STS;
2097 	I915_WRITE(MEMSWCTL, rgvswctl);
2098 	DELAY(1000);
2099 
2100 }
2101 
2102 void gen6_set_rps(struct drm_device *dev, u8 val)
2103 {
2104 	struct drm_i915_private *dev_priv = dev->dev_private;
2105 	u32 swreq;
2106 
2107 	swreq = (val & 0x3ff) << 25;
2108 	I915_WRITE(GEN6_RPNSWREQ, swreq);
2109 }
2110 
2111 void gen6_disable_rps(struct drm_device *dev)
2112 {
2113 	struct drm_i915_private *dev_priv = dev->dev_private;
2114 
2115 	I915_WRITE(GEN6_RPNSWREQ, 1 << 31);
2116 	I915_WRITE(GEN6_PMINTRMSK, 0xffffffff);
2117 	I915_WRITE(GEN6_PMIER, 0);
2118 	/* Complete PM interrupt masking here doesn't race with the rps work
2119 	 * item again unmasking PM interrupts because that is using a different
2120 	 * register (PMIMR) to mask PM interrupts. The only risk is in leaving
2121 	 * stale bits in PMIIR and PMIMR which gen6_enable_rps will clean up. */
2122 
2123 	spin_lock(&dev_priv->rps.lock);
2124 	dev_priv->rps.pm_iir = 0;
2125 	spin_unlock(&dev_priv->rps.lock);
2126 
2127 	I915_WRITE(GEN6_PMIIR, I915_READ(GEN6_PMIIR));
2128 }
2129 
2130 static unsigned long intel_pxfreq(u32 vidfreq)
2131 {
2132 	unsigned long freq;
2133 	int div = (vidfreq & 0x3f0000) >> 16;
2134 	int post = (vidfreq & 0x3000) >> 12;
2135 	int pre = (vidfreq & 0x7);
2136 
2137 	if (!pre)
2138 		return 0;
2139 
2140 	freq = ((div * 133333) / ((1<<post) * pre));
2141 
2142 	return freq;
2143 }
2144 
2145 static const struct cparams {
2146 	u16 i;
2147 	u16 t;
2148 	u16 m;
2149 	u16 c;
2150 } cparams[] = {
2151 	{ 1, 1333, 301, 28664 },
2152 	{ 1, 1066, 294, 24460 },
2153 	{ 1, 800, 294, 25192 },
2154 	{ 0, 1333, 276, 27605 },
2155 	{ 0, 1066, 276, 27605 },
2156 	{ 0, 800, 231, 23784 },
2157 };
2158 
2159 unsigned long i915_chipset_val(struct drm_i915_private *dev_priv)
2160 {
2161 	u64 total_count, diff, ret;
2162 	u32 count1, count2, count3, m = 0, c = 0;
2163 	unsigned long now = jiffies_to_msecs(jiffies), diff1;
2164 	int i;
2165 
2166 	diff1 = now - dev_priv->last_time1;
2167 	/*
2168 	 * sysctl(8) reads the value of sysctl twice in rapid
2169 	 * succession.  There is high chance that it happens in the
2170 	 * same timer tick.  Use the cached value to not divide by
2171 	 * zero and give the hw a chance to gather more samples.
2172 	 */
2173 	if (diff1 <= 10)
2174 		return (dev_priv->chipset_power);
2175 
2176 	count1 = I915_READ(DMIEC);
2177 	count2 = I915_READ(DDREC);
2178 	count3 = I915_READ(CSIEC);
2179 
2180 	total_count = count1 + count2 + count3;
2181 
2182 	/* FIXME: handle per-counter overflow */
2183 	if (total_count < dev_priv->last_count1) {
2184 		diff = ~0UL - dev_priv->last_count1;
2185 		diff += total_count;
2186 	} else {
2187 		diff = total_count - dev_priv->last_count1;
2188 	}
2189 
2190 	for (i = 0; i < DRM_ARRAY_SIZE(cparams); i++) {
2191 		if (cparams[i].i == dev_priv->c_m &&
2192 		    cparams[i].t == dev_priv->r_t) {
2193 			m = cparams[i].m;
2194 			c = cparams[i].c;
2195 			break;
2196 		}
2197 	}
2198 
2199 	diff = diff / diff1;
2200 	ret = ((m * diff) + c);
2201 	ret = ret / 10;
2202 
2203 	dev_priv->last_count1 = total_count;
2204 	dev_priv->last_time1 = now;
2205 
2206 	dev_priv->chipset_power = ret;
2207 	return (ret);
2208 }
2209 
2210 unsigned long i915_mch_val(struct drm_i915_private *dev_priv)
2211 {
2212 	unsigned long m, x, b;
2213 	u32 tsfs;
2214 
2215 	tsfs = I915_READ(TSFS);
2216 
2217 	m = ((tsfs & TSFS_SLOPE_MASK) >> TSFS_SLOPE_SHIFT);
2218 	x = I915_READ8(TR1);
2219 
2220 	b = tsfs & TSFS_INTR_MASK;
2221 
2222 	return ((m * x) / 127) - b;
2223 }
2224 
2225 static u16 pvid_to_extvid(struct drm_i915_private *dev_priv, u8 pxvid)
2226 {
2227 	static const struct v_table {
2228 		u16 vd; /* in .1 mil */
2229 		u16 vm; /* in .1 mil */
2230 	} v_table[] = {
2231 		{ 0, 0, },
2232 		{ 375, 0, },
2233 		{ 500, 0, },
2234 		{ 625, 0, },
2235 		{ 750, 0, },
2236 		{ 875, 0, },
2237 		{ 1000, 0, },
2238 		{ 1125, 0, },
2239 		{ 4125, 3000, },
2240 		{ 4125, 3000, },
2241 		{ 4125, 3000, },
2242 		{ 4125, 3000, },
2243 		{ 4125, 3000, },
2244 		{ 4125, 3000, },
2245 		{ 4125, 3000, },
2246 		{ 4125, 3000, },
2247 		{ 4125, 3000, },
2248 		{ 4125, 3000, },
2249 		{ 4125, 3000, },
2250 		{ 4125, 3000, },
2251 		{ 4125, 3000, },
2252 		{ 4125, 3000, },
2253 		{ 4125, 3000, },
2254 		{ 4125, 3000, },
2255 		{ 4125, 3000, },
2256 		{ 4125, 3000, },
2257 		{ 4125, 3000, },
2258 		{ 4125, 3000, },
2259 		{ 4125, 3000, },
2260 		{ 4125, 3000, },
2261 		{ 4125, 3000, },
2262 		{ 4125, 3000, },
2263 		{ 4250, 3125, },
2264 		{ 4375, 3250, },
2265 		{ 4500, 3375, },
2266 		{ 4625, 3500, },
2267 		{ 4750, 3625, },
2268 		{ 4875, 3750, },
2269 		{ 5000, 3875, },
2270 		{ 5125, 4000, },
2271 		{ 5250, 4125, },
2272 		{ 5375, 4250, },
2273 		{ 5500, 4375, },
2274 		{ 5625, 4500, },
2275 		{ 5750, 4625, },
2276 		{ 5875, 4750, },
2277 		{ 6000, 4875, },
2278 		{ 6125, 5000, },
2279 		{ 6250, 5125, },
2280 		{ 6375, 5250, },
2281 		{ 6500, 5375, },
2282 		{ 6625, 5500, },
2283 		{ 6750, 5625, },
2284 		{ 6875, 5750, },
2285 		{ 7000, 5875, },
2286 		{ 7125, 6000, },
2287 		{ 7250, 6125, },
2288 		{ 7375, 6250, },
2289 		{ 7500, 6375, },
2290 		{ 7625, 6500, },
2291 		{ 7750, 6625, },
2292 		{ 7875, 6750, },
2293 		{ 8000, 6875, },
2294 		{ 8125, 7000, },
2295 		{ 8250, 7125, },
2296 		{ 8375, 7250, },
2297 		{ 8500, 7375, },
2298 		{ 8625, 7500, },
2299 		{ 8750, 7625, },
2300 		{ 8875, 7750, },
2301 		{ 9000, 7875, },
2302 		{ 9125, 8000, },
2303 		{ 9250, 8125, },
2304 		{ 9375, 8250, },
2305 		{ 9500, 8375, },
2306 		{ 9625, 8500, },
2307 		{ 9750, 8625, },
2308 		{ 9875, 8750, },
2309 		{ 10000, 8875, },
2310 		{ 10125, 9000, },
2311 		{ 10250, 9125, },
2312 		{ 10375, 9250, },
2313 		{ 10500, 9375, },
2314 		{ 10625, 9500, },
2315 		{ 10750, 9625, },
2316 		{ 10875, 9750, },
2317 		{ 11000, 9875, },
2318 		{ 11125, 10000, },
2319 		{ 11250, 10125, },
2320 		{ 11375, 10250, },
2321 		{ 11500, 10375, },
2322 		{ 11625, 10500, },
2323 		{ 11750, 10625, },
2324 		{ 11875, 10750, },
2325 		{ 12000, 10875, },
2326 		{ 12125, 11000, },
2327 		{ 12250, 11125, },
2328 		{ 12375, 11250, },
2329 		{ 12500, 11375, },
2330 		{ 12625, 11500, },
2331 		{ 12750, 11625, },
2332 		{ 12875, 11750, },
2333 		{ 13000, 11875, },
2334 		{ 13125, 12000, },
2335 		{ 13250, 12125, },
2336 		{ 13375, 12250, },
2337 		{ 13500, 12375, },
2338 		{ 13625, 12500, },
2339 		{ 13750, 12625, },
2340 		{ 13875, 12750, },
2341 		{ 14000, 12875, },
2342 		{ 14125, 13000, },
2343 		{ 14250, 13125, },
2344 		{ 14375, 13250, },
2345 		{ 14500, 13375, },
2346 		{ 14625, 13500, },
2347 		{ 14750, 13625, },
2348 		{ 14875, 13750, },
2349 		{ 15000, 13875, },
2350 		{ 15125, 14000, },
2351 		{ 15250, 14125, },
2352 		{ 15375, 14250, },
2353 		{ 15500, 14375, },
2354 		{ 15625, 14500, },
2355 		{ 15750, 14625, },
2356 		{ 15875, 14750, },
2357 		{ 16000, 14875, },
2358 		{ 16125, 15000, },
2359 	};
2360 	if (dev_priv->info->is_mobile)
2361 		return v_table[pxvid].vm;
2362 	else
2363 		return v_table[pxvid].vd;
2364 }
2365 
2366 void i915_update_gfx_val(struct drm_i915_private *dev_priv)
2367 {
2368 	struct timespec now, diff1;
2369 	u64 diff;
2370 	unsigned long diffms;
2371 	u32 count;
2372 
2373 	if (dev_priv->info->gen != 5)
2374 		return;
2375 
2376 	nanotime(&now);
2377 	diff1 = now;
2378 	timespecsub(&diff1, &dev_priv->last_time2);
2379 
2380 	/* Don't divide by 0 */
2381 	diffms = diff1.tv_sec * 1000 + diff1.tv_nsec / 1000000;
2382 	if (!diffms)
2383 		return;
2384 
2385 	count = I915_READ(GFXEC);
2386 
2387 	if (count < dev_priv->last_count2) {
2388 		diff = ~0UL - dev_priv->last_count2;
2389 		diff += count;
2390 	} else {
2391 		diff = count - dev_priv->last_count2;
2392 	}
2393 
2394 	dev_priv->last_count2 = count;
2395 	dev_priv->last_time2 = now;
2396 
2397 	/* More magic constants... */
2398 	diff = diff * 1181;
2399 	diff = diff / (diffms * 10);
2400 	dev_priv->gfx_power = diff;
2401 }
2402 
2403 unsigned long i915_gfx_val(struct drm_i915_private *dev_priv)
2404 {
2405 	unsigned long t, corr, state1, corr2, state2;
2406 	u32 pxvid, ext_v;
2407 
2408 	pxvid = I915_READ(PXVFREQ_BASE + (dev_priv->rps.cur_delay * 4));
2409 	pxvid = (pxvid >> 24) & 0x7f;
2410 	ext_v = pvid_to_extvid(dev_priv, pxvid);
2411 
2412 	state1 = ext_v;
2413 
2414 	t = i915_mch_val(dev_priv);
2415 
2416 	/* Revel in the empirically derived constants */
2417 
2418 	/* Correction factor in 1/100000 units */
2419 	if (t > 80)
2420 		corr = ((t * 2349) + 135940);
2421 	else if (t >= 50)
2422 		corr = ((t * 964) + 29317);
2423 	else /* < 50 */
2424 		corr = ((t * 301) + 1004);
2425 
2426 	corr = corr * ((150142 * state1) / 10000 - 78642);
2427 	corr /= 100000;
2428 	corr2 = (corr * dev_priv->corr);
2429 
2430 	state2 = (corr2 * state1) / 10000;
2431 	state2 /= 100; /* convert to mW */
2432 
2433 	i915_update_gfx_val(dev_priv);
2434 
2435 	return dev_priv->gfx_power + state2;
2436 }
2437 
2438 /**
2439  * i915_read_mch_val - return value for IPS use
2440  *
2441  * Calculate and return a value for the IPS driver to use when deciding whether
2442  * we have thermal and power headroom to increase CPU or GPU power budget.
2443  */
2444 unsigned long i915_read_mch_val(void)
2445 {
2446 	struct drm_i915_private *dev_priv;
2447 	unsigned long chipset_val, graphics_val, ret = 0;
2448 
2449 	lockmgr(&mchdev_lock, LK_EXCLUSIVE);
2450 	if (!i915_mch_dev)
2451 		goto out_unlock;
2452 	dev_priv = i915_mch_dev;
2453 
2454 	chipset_val = i915_chipset_val(dev_priv);
2455 	graphics_val = i915_gfx_val(dev_priv);
2456 
2457 	ret = chipset_val + graphics_val;
2458 
2459 out_unlock:
2460 	lockmgr(&mchdev_lock, LK_RELEASE);
2461 
2462 	return ret;
2463 }
2464 
2465 /**
2466  * i915_gpu_raise - raise GPU frequency limit
2467  *
2468  * Raise the limit; IPS indicates we have thermal headroom.
2469  */
2470 bool i915_gpu_raise(void)
2471 {
2472 	struct drm_i915_private *dev_priv;
2473 	bool ret = true;
2474 
2475 	lockmgr(&mchdev_lock, LK_EXCLUSIVE);
2476 	if (!i915_mch_dev) {
2477 		ret = false;
2478 		goto out_unlock;
2479 	}
2480 	dev_priv = i915_mch_dev;
2481 
2482 	if (dev_priv->rps.max_delay > dev_priv->fmax)
2483 		dev_priv->rps.max_delay--;
2484 
2485 out_unlock:
2486 	lockmgr(&mchdev_lock, LK_RELEASE);
2487 
2488 	return ret;
2489 }
2490 
2491 /**
2492  * i915_gpu_lower - lower GPU frequency limit
2493  *
2494  * IPS indicates we're close to a thermal limit, so throttle back the GPU
2495  * frequency maximum.
2496  */
2497 bool i915_gpu_lower(void)
2498 {
2499 	struct drm_i915_private *dev_priv;
2500 	bool ret = true;
2501 
2502 	lockmgr(&mchdev_lock, LK_EXCLUSIVE);
2503 	if (!i915_mch_dev) {
2504 		ret = false;
2505 		goto out_unlock;
2506 	}
2507 	dev_priv = i915_mch_dev;
2508 
2509 	if (dev_priv->rps.max_delay < dev_priv->rps.min_delay)
2510 		dev_priv->rps.max_delay++;
2511 
2512 out_unlock:
2513 	lockmgr(&mchdev_lock, LK_RELEASE);
2514 
2515 	return ret;
2516 }
2517 
2518 /**
2519  * i915_gpu_busy - indicate GPU business to IPS
2520  *
2521  * Tell the IPS driver whether or not the GPU is busy.
2522  */
2523 bool i915_gpu_busy(void)
2524 {
2525 	struct drm_i915_private *dev_priv;
2526 	bool ret = false;
2527 
2528 	lockmgr(&mchdev_lock, LK_EXCLUSIVE);
2529 	if (!i915_mch_dev)
2530 		goto out_unlock;
2531 	dev_priv = i915_mch_dev;
2532 
2533 	ret = dev_priv->busy;
2534 
2535 out_unlock:
2536 	lockmgr(&mchdev_lock, LK_RELEASE);
2537 
2538 	return ret;
2539 }
2540 
2541 /**
2542  * i915_gpu_turbo_disable - disable graphics turbo
2543  *
2544  * Disable graphics turbo by resetting the max frequency and setting the
2545  * current frequency to the default.
2546  */
2547 bool i915_gpu_turbo_disable(void)
2548 {
2549 	struct drm_i915_private *dev_priv;
2550 	bool ret = true;
2551 
2552 	lockmgr(&mchdev_lock, LK_EXCLUSIVE);
2553 	if (!i915_mch_dev) {
2554 		ret = false;
2555 		goto out_unlock;
2556 	}
2557 	dev_priv = i915_mch_dev;
2558 
2559 	dev_priv->rps.max_delay = dev_priv->fstart;
2560 
2561 	if (!ironlake_set_drps(dev_priv->dev, dev_priv->fstart))
2562 		ret = false;
2563 
2564 out_unlock:
2565 	lockmgr(&mchdev_lock, LK_RELEASE);
2566 
2567 	return ret;
2568 }
2569 
2570 void intel_init_emon(struct drm_device *dev)
2571 {
2572 	struct drm_i915_private *dev_priv = dev->dev_private;
2573 	u32 lcfuse;
2574 	u8 pxw[16];
2575 	int i;
2576 
2577 	/* Disable to program */
2578 	I915_WRITE(ECR, 0);
2579 	POSTING_READ(ECR);
2580 
2581 	/* Program energy weights for various events */
2582 	I915_WRITE(SDEW, 0x15040d00);
2583 	I915_WRITE(CSIEW0, 0x007f0000);
2584 	I915_WRITE(CSIEW1, 0x1e220004);
2585 	I915_WRITE(CSIEW2, 0x04000004);
2586 
2587 	for (i = 0; i < 5; i++)
2588 		I915_WRITE(PEW + (i * 4), 0);
2589 	for (i = 0; i < 3; i++)
2590 		I915_WRITE(DEW + (i * 4), 0);
2591 
2592 	/* Program P-state weights to account for frequency power adjustment */
2593 	for (i = 0; i < 16; i++) {
2594 		u32 pxvidfreq = I915_READ(PXVFREQ_BASE + (i * 4));
2595 		unsigned long freq = intel_pxfreq(pxvidfreq);
2596 		unsigned long vid = (pxvidfreq & PXVFREQ_PX_MASK) >>
2597 			PXVFREQ_PX_SHIFT;
2598 		unsigned long val;
2599 
2600 		val = vid * vid;
2601 		val *= (freq / 1000);
2602 		val *= 255;
2603 		val /= (127*127*900);
2604 		if (val > 0xff)
2605 			DRM_ERROR("bad pxval: %ld\n", val);
2606 		pxw[i] = val;
2607 	}
2608 	/* Render standby states get 0 weight */
2609 	pxw[14] = 0;
2610 	pxw[15] = 0;
2611 
2612 	for (i = 0; i < 4; i++) {
2613 		u32 val = (pxw[i*4] << 24) | (pxw[(i*4)+1] << 16) |
2614 			(pxw[(i*4)+2] << 8) | (pxw[(i*4)+3]);
2615 		I915_WRITE(PXW + (i * 4), val);
2616 	}
2617 
2618 	/* Adjust magic regs to magic values (more experimental results) */
2619 	I915_WRITE(OGW0, 0);
2620 	I915_WRITE(OGW1, 0);
2621 	I915_WRITE(EG0, 0x00007f00);
2622 	I915_WRITE(EG1, 0x0000000e);
2623 	I915_WRITE(EG2, 0x000e0000);
2624 	I915_WRITE(EG3, 0x68000300);
2625 	I915_WRITE(EG4, 0x42000000);
2626 	I915_WRITE(EG5, 0x00140031);
2627 	I915_WRITE(EG6, 0);
2628 	I915_WRITE(EG7, 0);
2629 
2630 	for (i = 0; i < 8; i++)
2631 		I915_WRITE(PXWL + (i * 4), 0);
2632 
2633 	/* Enable PMON + select events */
2634 	I915_WRITE(ECR, 0x80000019);
2635 
2636 	lcfuse = I915_READ(LCFUSE02);
2637 
2638 	dev_priv->corr = (lcfuse & LCFUSE_HIV_MASK);
2639 }
2640 
2641 static int intel_enable_rc6(struct drm_device *dev)
2642 {
2643 	/*
2644 	 * Respect the kernel parameter if it is set
2645 	 */
2646 	if (i915_enable_rc6 >= 0)
2647 		return i915_enable_rc6;
2648 
2649 	/*
2650 	 * Disable RC6 on Ironlake
2651 	 */
2652 	if (INTEL_INFO(dev)->gen == 5)
2653 		return 0;
2654 
2655 	/*
2656 	 * Enable rc6 on Sandybridge if DMA remapping is disabled
2657 	 */
2658 	if (INTEL_INFO(dev)->gen == 6) {
2659 		DRM_DEBUG_DRIVER(
2660 		    "Sandybridge: intel_iommu_enabled %s -- RC6 %sabled\n",
2661 		     intel_iommu_enabled ? "true" : "false",
2662 		     !intel_iommu_enabled ? "en" : "dis");
2663 		return (intel_iommu_enabled ? 0 : INTEL_RC6_ENABLE);
2664 	}
2665 	DRM_DEBUG_DRIVER("RC6 and deep RC6 enabled\n");
2666 	return (INTEL_RC6_ENABLE | INTEL_RC6p_ENABLE);
2667 }
2668 
2669 void gen6_enable_rps(struct drm_i915_private *dev_priv)
2670 {
2671 	u32 rp_state_cap = I915_READ(GEN6_RP_STATE_CAP);
2672 	u32 gt_perf_status = I915_READ(GEN6_GT_PERF_STATUS);
2673 	u32 pcu_mbox, rc6_mask = 0;
2674 	u32 gtfifodbg;
2675 	int cur_freq, min_freq, max_freq;
2676 	int rc6_mode;
2677 	int i;
2678 
2679 	/* Here begins a magic sequence of register writes to enable
2680 	 * auto-downclocking.
2681 	 *
2682 	 * Perhaps there might be some value in exposing these to
2683 	 * userspace...
2684 	 */
2685 	I915_WRITE(GEN6_RC_STATE, 0);
2686 
2687 	/* Clear the DBG now so we don't confuse earlier errors */
2688 	if ((gtfifodbg = I915_READ(GTFIFODBG))) {
2689 		DRM_ERROR("GT fifo had a previous error %x\n", gtfifodbg);
2690 		I915_WRITE(GTFIFODBG, gtfifodbg);
2691 	}
2692 
2693 	gen6_gt_force_wake_get(dev_priv);
2694 
2695 	/* disable the counters and set deterministic thresholds */
2696 	I915_WRITE(GEN6_RC_CONTROL, 0);
2697 
2698 	I915_WRITE(GEN6_RC1_WAKE_RATE_LIMIT, 1000 << 16);
2699 	I915_WRITE(GEN6_RC6_WAKE_RATE_LIMIT, 40 << 16 | 30);
2700 	I915_WRITE(GEN6_RC6pp_WAKE_RATE_LIMIT, 30);
2701 	I915_WRITE(GEN6_RC_EVALUATION_INTERVAL, 125000);
2702 	I915_WRITE(GEN6_RC_IDLE_HYSTERSIS, 25);
2703 
2704 	for (i = 0; i < I915_NUM_RINGS; i++)
2705 		I915_WRITE(RING_MAX_IDLE(dev_priv->ring[i].mmio_base), 10);
2706 
2707 	I915_WRITE(GEN6_RC_SLEEP, 0);
2708 	I915_WRITE(GEN6_RC1e_THRESHOLD, 1000);
2709 	I915_WRITE(GEN6_RC6_THRESHOLD, 50000);
2710 	I915_WRITE(GEN6_RC6p_THRESHOLD, 100000);
2711 	I915_WRITE(GEN6_RC6pp_THRESHOLD, 64000); /* unused */
2712 
2713 	rc6_mode = intel_enable_rc6(dev_priv->dev);
2714 	if (rc6_mode & INTEL_RC6_ENABLE)
2715 		rc6_mask |= GEN6_RC_CTL_RC6_ENABLE;
2716 
2717 	if (rc6_mode & INTEL_RC6p_ENABLE)
2718 		rc6_mask |= GEN6_RC_CTL_RC6p_ENABLE;
2719 
2720 	if (rc6_mode & INTEL_RC6pp_ENABLE)
2721 		rc6_mask |= GEN6_RC_CTL_RC6pp_ENABLE;
2722 
2723 	DRM_INFO("Enabling RC6 states: RC6 %s, RC6p %s, RC6pp %s\n",
2724 			(rc6_mode & INTEL_RC6_ENABLE) ? "on" : "off",
2725 			(rc6_mode & INTEL_RC6p_ENABLE) ? "on" : "off",
2726 			(rc6_mode & INTEL_RC6pp_ENABLE) ? "on" : "off");
2727 
2728 	I915_WRITE(GEN6_RC_CONTROL,
2729 		   rc6_mask |
2730 		   GEN6_RC_CTL_EI_MODE(1) |
2731 		   GEN6_RC_CTL_HW_ENABLE);
2732 
2733 	I915_WRITE(GEN6_RPNSWREQ,
2734 		   GEN6_FREQUENCY(10) |
2735 		   GEN6_OFFSET(0) |
2736 		   GEN6_AGGRESSIVE_TURBO);
2737 	I915_WRITE(GEN6_RC_VIDEO_FREQ,
2738 		   GEN6_FREQUENCY(12));
2739 
2740 	I915_WRITE(GEN6_RP_DOWN_TIMEOUT, 1000000);
2741 	I915_WRITE(GEN6_RP_INTERRUPT_LIMITS,
2742 		   18 << 24 |
2743 		   6 << 16);
2744 	I915_WRITE(GEN6_RP_UP_THRESHOLD, 10000);
2745 	I915_WRITE(GEN6_RP_DOWN_THRESHOLD, 1000000);
2746 	I915_WRITE(GEN6_RP_UP_EI, 100000);
2747 	I915_WRITE(GEN6_RP_DOWN_EI, 5000000);
2748 	I915_WRITE(GEN6_RP_IDLE_HYSTERSIS, 10);
2749 	I915_WRITE(GEN6_RP_CONTROL,
2750 		   GEN6_RP_MEDIA_TURBO |
2751 		   GEN6_RP_MEDIA_HW_MODE |
2752 		   GEN6_RP_MEDIA_IS_GFX |
2753 		   GEN6_RP_ENABLE |
2754 		   GEN6_RP_UP_BUSY_AVG |
2755 		   GEN6_RP_DOWN_IDLE_CONT);
2756 
2757 	if (_intel_wait_for(dev,
2758 	    (I915_READ(GEN6_PCODE_MAILBOX) & GEN6_PCODE_READY) == 0, 500,
2759 	    1, "915pr1"))
2760 		DRM_ERROR("timeout waiting for pcode mailbox to become idle\n");
2761 
2762 	I915_WRITE(GEN6_PCODE_DATA, 0);
2763 	I915_WRITE(GEN6_PCODE_MAILBOX,
2764 		   GEN6_PCODE_READY |
2765 		   GEN6_PCODE_WRITE_MIN_FREQ_TABLE);
2766 	if (_intel_wait_for(dev,
2767 	    (I915_READ(GEN6_PCODE_MAILBOX) & GEN6_PCODE_READY) == 0, 500,
2768 	    1, "915pr2"))
2769 		DRM_ERROR("timeout waiting for pcode mailbox to finish\n");
2770 
2771 	min_freq = (rp_state_cap & 0xff0000) >> 16;
2772 	max_freq = rp_state_cap & 0xff;
2773 	cur_freq = (gt_perf_status & 0xff00) >> 8;
2774 
2775 	/* Check for overclock support */
2776 	if (_intel_wait_for(dev,
2777 	    (I915_READ(GEN6_PCODE_MAILBOX) & GEN6_PCODE_READY) == 0, 500,
2778 	    1, "915pr3"))
2779 		DRM_ERROR("timeout waiting for pcode mailbox to become idle\n");
2780 	I915_WRITE(GEN6_PCODE_MAILBOX, GEN6_READ_OC_PARAMS);
2781 	pcu_mbox = I915_READ(GEN6_PCODE_DATA);
2782 	if (_intel_wait_for(dev,
2783 	    (I915_READ(GEN6_PCODE_MAILBOX) & GEN6_PCODE_READY) == 0, 500,
2784 	    1, "915pr4"))
2785 		DRM_ERROR("timeout waiting for pcode mailbox to finish\n");
2786 	if (pcu_mbox & (1<<31)) { /* OC supported */
2787 		max_freq = pcu_mbox & 0xff;
2788 		DRM_DEBUG("overclocking supported, adjusting frequency max to %dMHz\n", pcu_mbox * 50);
2789 	}
2790 
2791 	/* In units of 100MHz */
2792 	dev_priv->rps.max_delay = max_freq;
2793 	dev_priv->rps.min_delay = min_freq;
2794 	dev_priv->rps.cur_delay = cur_freq;
2795 
2796 	/* requires MSI enabled */
2797 	I915_WRITE(GEN6_PMIER,
2798 		   GEN6_PM_MBOX_EVENT |
2799 		   GEN6_PM_THERMAL_EVENT |
2800 		   GEN6_PM_RP_DOWN_TIMEOUT |
2801 		   GEN6_PM_RP_UP_THRESHOLD |
2802 		   GEN6_PM_RP_DOWN_THRESHOLD |
2803 		   GEN6_PM_RP_UP_EI_EXPIRED |
2804 		   GEN6_PM_RP_DOWN_EI_EXPIRED);
2805 	spin_lock(&dev_priv->rps.lock);
2806 	WARN_ON(dev_priv->rps.pm_iir != 0);
2807 	I915_WRITE(GEN6_PMIMR, 0);
2808 	spin_unlock(&dev_priv->rps.lock);
2809 	/* enable all PM interrupts */
2810 	I915_WRITE(GEN6_PMINTRMSK, 0);
2811 
2812 	gen6_gt_force_wake_put(dev_priv);
2813 }
2814 
2815 void gen6_update_ring_freq(struct drm_i915_private *dev_priv)
2816 {
2817 	struct drm_device *dev;
2818 	int min_freq = 15;
2819 	int gpu_freq, ia_freq, max_ia_freq;
2820 	int scaling_factor = 180;
2821 	uint64_t tsc_freq;
2822 
2823 	dev = dev_priv->dev;
2824 #if 0
2825 	max_ia_freq = cpufreq_quick_get_max(0);
2826 	/*
2827 	 * Default to measured freq if none found, PCU will ensure we don't go
2828 	 * over
2829 	 */
2830 	if (!max_ia_freq)
2831 		max_ia_freq = tsc_freq;
2832 
2833 	/* Convert from Hz to MHz */
2834 	max_ia_freq /= 1000;
2835 #else
2836 	tsc_freq = atomic_load_acq_64(&tsc_freq);
2837 	max_ia_freq = tsc_freq / 1000 / 1000;
2838 #endif
2839 
2840 	DRM_LOCK(dev);
2841 
2842 	/*
2843 	 * For each potential GPU frequency, load a ring frequency we'd like
2844 	 * to use for memory access.  We do this by specifying the IA frequency
2845 	 * the PCU should use as a reference to determine the ring frequency.
2846 	 */
2847 	for (gpu_freq = dev_priv->rps.max_delay; gpu_freq >= dev_priv->rps.min_delay;
2848 	     gpu_freq--) {
2849 		int diff = dev_priv->rps.max_delay - gpu_freq;
2850 		int d;
2851 
2852 		/*
2853 		 * For GPU frequencies less than 750MHz, just use the lowest
2854 		 * ring freq.
2855 		 */
2856 		if (gpu_freq < min_freq)
2857 			ia_freq = 800;
2858 		else
2859 			ia_freq = max_ia_freq - ((diff * scaling_factor) / 2);
2860 		d = 100;
2861 		ia_freq = (ia_freq + d / 2) / d;
2862 
2863 		I915_WRITE(GEN6_PCODE_DATA,
2864 			   (ia_freq << GEN6_PCODE_FREQ_IA_RATIO_SHIFT) |
2865 			   gpu_freq);
2866 		I915_WRITE(GEN6_PCODE_MAILBOX, GEN6_PCODE_READY |
2867 			   GEN6_PCODE_WRITE_MIN_FREQ_TABLE);
2868 		if (_intel_wait_for(dev,
2869 		    (I915_READ(GEN6_PCODE_MAILBOX) & GEN6_PCODE_READY) == 0,
2870 		    10, 1, "915frq")) {
2871 			DRM_ERROR("pcode write of freq table timed out\n");
2872 			continue;
2873 		}
2874 	}
2875 
2876 	DRM_UNLOCK(dev);
2877 }
2878 
2879 void ironlake_init_clock_gating(struct drm_device *dev)
2880 {
2881 	struct drm_i915_private *dev_priv = dev->dev_private;
2882 	uint32_t dspclk_gate = ILK_VRHUNIT_CLOCK_GATE_DISABLE;
2883 
2884 	/* Required for FBC */
2885 	dspclk_gate |= ILK_DPFCRUNIT_CLOCK_GATE_DISABLE |
2886 		   ILK_DPFCUNIT_CLOCK_GATE_DISABLE |
2887 		   ILK_DPFDUNIT_CLOCK_GATE_ENABLE;
2888 
2889 	I915_WRITE(PCH_3DCGDIS0,
2890 		   MARIUNIT_CLOCK_GATE_DISABLE |
2891 		   SVSMUNIT_CLOCK_GATE_DISABLE);
2892 	I915_WRITE(PCH_3DCGDIS1,
2893 		   VFMUNIT_CLOCK_GATE_DISABLE);
2894 
2895 	/*
2896 	 * According to the spec the following bits should be set in
2897 	 * order to enable memory self-refresh
2898 	 * The bit 22/21 of 0x42004
2899 	 * The bit 5 of 0x42020
2900 	 * The bit 15 of 0x45000
2901 	 */
2902 	I915_WRITE(ILK_DISPLAY_CHICKEN2,
2903 		   (I915_READ(ILK_DISPLAY_CHICKEN2) |
2904 		    ILK_DPARB_GATE | ILK_VSDPFD_FULL));
2905 	dspclk_gate |= ILK_DPARBUNIT_CLOCK_GATE_ENABLE;
2906 	I915_WRITE(DISP_ARB_CTL,
2907 		   (I915_READ(DISP_ARB_CTL) |
2908 		    DISP_FBC_WM_DIS));
2909 	I915_WRITE(WM3_LP_ILK, 0);
2910 	I915_WRITE(WM2_LP_ILK, 0);
2911 	I915_WRITE(WM1_LP_ILK, 0);
2912 
2913 	/*
2914 	 * Based on the document from hardware guys the following bits
2915 	 * should be set unconditionally in order to enable FBC.
2916 	 * The bit 22 of 0x42000
2917 	 * The bit 22 of 0x42004
2918 	 * The bit 7,8,9 of 0x42020.
2919 	 */
2920 	if (IS_IRONLAKE_M(dev)) {
2921 		I915_WRITE(ILK_DISPLAY_CHICKEN1,
2922 			   I915_READ(ILK_DISPLAY_CHICKEN1) |
2923 			   ILK_FBCQ_DIS);
2924 		I915_WRITE(ILK_DISPLAY_CHICKEN2,
2925 			   I915_READ(ILK_DISPLAY_CHICKEN2) |
2926 			   ILK_DPARB_GATE);
2927 	}
2928 
2929 	I915_WRITE(ILK_DSPCLK_GATE_D, dspclk_gate);
2930 
2931 	I915_WRITE(ILK_DISPLAY_CHICKEN2,
2932 		   I915_READ(ILK_DISPLAY_CHICKEN2) |
2933 		   ILK_ELPIN_409_SELECT);
2934 	I915_WRITE(_3D_CHICKEN2,
2935 		   _3D_CHICKEN2_WM_READ_PIPELINED << 16 |
2936 		   _3D_CHICKEN2_WM_READ_PIPELINED);
2937 
2938 	/* WaDisableRenderCachePipelinedFlush */
2939 	I915_WRITE(CACHE_MODE_0,
2940 		   _MASKED_BIT_ENABLE(CM0_PIPELINED_RENDER_FLUSH_DISABLE));
2941 
2942 	ibx_init_clock_gating(dev);
2943 }
2944 
2945 void cpt_init_clock_gating(struct drm_device *dev)
2946 {
2947 	struct drm_i915_private *dev_priv = dev->dev_private;
2948 	int pipe;
2949 
2950 	/*
2951 	 * On Ibex Peak and Cougar Point, we need to disable clock
2952 	 * gating for the panel power sequencer or it will fail to
2953 	 * start up when no ports are active.
2954 	 */
2955 	I915_WRITE(SOUTH_DSPCLK_GATE_D, PCH_DPLSUNIT_CLOCK_GATE_DISABLE);
2956 	I915_WRITE(SOUTH_CHICKEN2, I915_READ(SOUTH_CHICKEN2) |
2957 		   DPLS_EDP_PPS_FIX_DIS);
2958 	/* The below fixes the weird display corruption, a few pixels shifted
2959 	 * downward, on (only) LVDS of some HP laptops with IVY.
2960 	 */
2961 	for_each_pipe(pipe)
2962 		I915_WRITE(TRANS_CHICKEN2(pipe), TRANS_CHICKEN2_TIMING_OVERRIDE);
2963 	/* WADP0ClockGatingDisable */
2964 	for_each_pipe(pipe) {
2965 		I915_WRITE(TRANS_CHICKEN1(pipe),
2966 			   TRANS_CHICKEN1_DP0UNIT_GC_DISABLE);
2967 	}
2968 }
2969 
2970 void gen6_init_clock_gating(struct drm_device *dev)
2971 {
2972 	struct drm_i915_private *dev_priv = dev->dev_private;
2973 	int pipe;
2974 	uint32_t dspclk_gate = ILK_VRHUNIT_CLOCK_GATE_DISABLE;
2975 
2976 	I915_WRITE(ILK_DSPCLK_GATE_D, dspclk_gate);
2977 
2978 	I915_WRITE(ILK_DISPLAY_CHICKEN2,
2979 		   I915_READ(ILK_DISPLAY_CHICKEN2) |
2980 		   ILK_ELPIN_409_SELECT);
2981 
2982 	/* WaDisableHiZPlanesWhenMSAAEnabled */
2983 	I915_WRITE(_3D_CHICKEN,
2984 		   _MASKED_BIT_ENABLE(_3D_CHICKEN_HIZ_PLANE_DISABLE_MSAA_4X_SNB));
2985 
2986 	/* WaSetupGtModeTdRowDispatch */
2987 	if (IS_SNB_GT1(dev))
2988 		I915_WRITE(GEN6_GT_MODE,
2989 			   _MASKED_BIT_ENABLE(GEN6_TD_FOUR_ROW_DISPATCH_DISABLE));
2990 
2991 	I915_WRITE(WM3_LP_ILK, 0);
2992 	I915_WRITE(WM2_LP_ILK, 0);
2993 	I915_WRITE(WM1_LP_ILK, 0);
2994 
2995 	I915_WRITE(CACHE_MODE_0,
2996 		   _MASKED_BIT_DISABLE(CM0_STC_EVICT_DISABLE_LRA_SNB));
2997 
2998 	I915_WRITE(GEN6_UCGCTL1,
2999 		   I915_READ(GEN6_UCGCTL1) |
3000 		   GEN6_BLBUNIT_CLOCK_GATE_DISABLE |
3001 		   GEN6_CSUNIT_CLOCK_GATE_DISABLE);
3002 
3003 	/* According to the BSpec vol1g, bit 12 (RCPBUNIT) clock
3004 	 * gating disable must be set.  Failure to set it results in
3005 	 * flickering pixels due to Z write ordering failures after
3006 	 * some amount of runtime in the Mesa "fire" demo, and Unigine
3007 	 * Sanctuary and Tropics, and apparently anything else with
3008 	 * alpha test or pixel discard.
3009 	 *
3010 	 * According to the spec, bit 11 (RCCUNIT) must also be set,
3011 	 * but we didn't debug actual testcases to find it out.
3012 	 *
3013 	 * Also apply WaDisableVDSUnitClockGating and
3014 	 * WaDisableRCPBUnitClockGating.
3015 	 */
3016 	I915_WRITE(GEN6_UCGCTL2,
3017 		   GEN7_VDSUNIT_CLOCK_GATE_DISABLE |
3018 		   GEN6_RCPBUNIT_CLOCK_GATE_DISABLE |
3019 		   GEN6_RCCUNIT_CLOCK_GATE_DISABLE);
3020 
3021 	/* Bspec says we need to always set all mask bits. */
3022 	I915_WRITE(_3D_CHICKEN3, (0xFFFF << 16) |
3023 		   _3D_CHICKEN3_SF_DISABLE_FASTCLIP_CULL);
3024 
3025 	/*
3026 	 * According to the spec the following bits should be
3027 	 * set in order to enable memory self-refresh and fbc:
3028 	 * The bit21 and bit22 of 0x42000
3029 	 * The bit21 and bit22 of 0x42004
3030 	 * The bit5 and bit7 of 0x42020
3031 	 * The bit14 of 0x70180
3032 	 * The bit14 of 0x71180
3033 	 */
3034 	I915_WRITE(ILK_DISPLAY_CHICKEN1,
3035 		   I915_READ(ILK_DISPLAY_CHICKEN1) |
3036 		   ILK_FBCQ_DIS | ILK_PABSTRETCH_DIS);
3037 	I915_WRITE(ILK_DISPLAY_CHICKEN2,
3038 		   I915_READ(ILK_DISPLAY_CHICKEN2) |
3039 		   ILK_DPARB_GATE | ILK_VSDPFD_FULL);
3040 	I915_WRITE(ILK_DSPCLK_GATE_D,
3041 		   I915_READ(ILK_DSPCLK_GATE_D) |
3042 		   ILK_DPARBUNIT_CLOCK_GATE_ENABLE  |
3043 		   ILK_DPFDUNIT_CLOCK_GATE_ENABLE);
3044 
3045 	/* WaMbcDriverBootEnable */
3046 	I915_WRITE(GEN6_MBCTL, I915_READ(GEN6_MBCTL) |
3047 		   GEN6_MBCTL_ENABLE_BOOT_FETCH);
3048 
3049 	for_each_pipe(pipe) {
3050 		I915_WRITE(DSPCNTR(pipe),
3051 			   I915_READ(DSPCNTR(pipe)) |
3052 			   DISPPLANE_TRICKLE_FEED_DISABLE);
3053 		intel_flush_display_plane(dev_priv, pipe);
3054 	}
3055 
3056 	/* The default value should be 0x200 according to docs, but the two
3057 	 * platforms I checked have a 0 for this. (Maybe BIOS overrides?) */
3058 	I915_WRITE(GEN6_GT_MODE, _MASKED_BIT_DISABLE(0xffff));
3059 	I915_WRITE(GEN6_GT_MODE, _MASKED_BIT_ENABLE(GEN6_GT_MODE_HI));
3060 
3061 	cpt_init_clock_gating(dev);
3062 }
3063 
3064 void ivybridge_init_clock_gating(struct drm_device *dev)
3065 {
3066 	struct drm_i915_private *dev_priv = dev->dev_private;
3067 	int pipe;
3068 	uint32_t dspclk_gate = VRHUNIT_CLOCK_GATE_DISABLE;
3069 
3070 	I915_WRITE(ILK_DSPCLK_GATE_D, dspclk_gate);
3071 
3072 	I915_WRITE(WM3_LP_ILK, 0);
3073 	I915_WRITE(WM2_LP_ILK, 0);
3074 	I915_WRITE(WM1_LP_ILK, 0);
3075 
3076 	/* According to the spec, bit 13 (RCZUNIT) must be set on IVB.
3077 	 * This implements the WaDisableRCZUnitClockGating workaround.
3078 	 */
3079 	I915_WRITE(GEN6_UCGCTL2, GEN6_RCZUNIT_CLOCK_GATE_DISABLE);
3080 
3081 	I915_WRITE(ILK_DSPCLK_GATE_D, ILK_VRHUNIT_CLOCK_GATE_DISABLE);
3082 
3083 	I915_WRITE(IVB_CHICKEN3,
3084 		   CHICKEN3_DGMG_REQ_OUT_FIX_DISABLE |
3085 		   CHICKEN3_DGMG_DONE_FIX_DISABLE);
3086 
3087 	/* Apply the WaDisableRHWOOptimizationForRenderHang workaround. */
3088 	I915_WRITE(GEN7_COMMON_SLICE_CHICKEN1,
3089 		   GEN7_CSC1_RHWO_OPT_DISABLE_IN_RCC);
3090 
3091 	/* WaApplyL3ControlAndL3ChickenMode requires those two on Ivy Bridge */
3092 	I915_WRITE(GEN7_L3CNTLREG1,
3093 			GEN7_WA_FOR_GEN7_L3_CONTROL);
3094 	I915_WRITE(GEN7_L3_CHICKEN_MODE_REGISTER,
3095 			GEN7_WA_L3_CHICKEN_MODE);
3096 
3097 	/* This is required by WaCatErrorRejectionIssue */
3098 	I915_WRITE(GEN7_SQ_CHICKEN_MBCUNIT_CONFIG,
3099 			I915_READ(GEN7_SQ_CHICKEN_MBCUNIT_CONFIG) |
3100 			GEN7_SQ_CHICKEN_MBCUNIT_SQINTMOB);
3101 
3102 	for_each_pipe(pipe) {
3103 		I915_WRITE(DSPCNTR(pipe),
3104 			   I915_READ(DSPCNTR(pipe)) |
3105 			   DISPPLANE_TRICKLE_FEED_DISABLE);
3106 		intel_flush_display_plane(dev_priv, pipe);
3107 	}
3108 }
3109 
3110 void g4x_init_clock_gating(struct drm_device *dev)
3111 {
3112 	struct drm_i915_private *dev_priv = dev->dev_private;
3113 	uint32_t dspclk_gate;
3114 
3115 	I915_WRITE(RENCLK_GATE_D1, 0);
3116 	I915_WRITE(RENCLK_GATE_D2, VF_UNIT_CLOCK_GATE_DISABLE |
3117 		   GS_UNIT_CLOCK_GATE_DISABLE |
3118 		   CL_UNIT_CLOCK_GATE_DISABLE);
3119 	I915_WRITE(RAMCLK_GATE_D, 0);
3120 	dspclk_gate = VRHUNIT_CLOCK_GATE_DISABLE |
3121 		OVRUNIT_CLOCK_GATE_DISABLE |
3122 		OVCUNIT_CLOCK_GATE_DISABLE;
3123 	if (IS_GM45(dev))
3124 		dspclk_gate |= DSSUNIT_CLOCK_GATE_DISABLE;
3125 	I915_WRITE(DSPCLK_GATE_D, dspclk_gate);
3126 }
3127 
3128 void crestline_init_clock_gating(struct drm_device *dev)
3129 {
3130 	struct drm_i915_private *dev_priv = dev->dev_private;
3131 
3132 	I915_WRITE(RENCLK_GATE_D1, I965_RCC_CLOCK_GATE_DISABLE);
3133 	I915_WRITE(RENCLK_GATE_D2, 0);
3134 	I915_WRITE(DSPCLK_GATE_D, 0);
3135 	I915_WRITE(RAMCLK_GATE_D, 0);
3136 	I915_WRITE16(DEUC, 0);
3137 }
3138 
3139 void broadwater_init_clock_gating(struct drm_device *dev)
3140 {
3141 	struct drm_i915_private *dev_priv = dev->dev_private;
3142 
3143 	I915_WRITE(RENCLK_GATE_D1, I965_RCZ_CLOCK_GATE_DISABLE |
3144 		   I965_RCC_CLOCK_GATE_DISABLE |
3145 		   I965_RCPB_CLOCK_GATE_DISABLE |
3146 		   I965_ISC_CLOCK_GATE_DISABLE |
3147 		   I965_FBC_CLOCK_GATE_DISABLE);
3148 	I915_WRITE(RENCLK_GATE_D2, 0);
3149 }
3150 
3151 void gen3_init_clock_gating(struct drm_device *dev)
3152 {
3153 	struct drm_i915_private *dev_priv = dev->dev_private;
3154 	u32 dstate = I915_READ(D_STATE);
3155 
3156 	dstate |= DSTATE_PLL_D3_OFF | DSTATE_GFX_CLOCK_GATING |
3157 		DSTATE_DOT_CLOCK_GATING;
3158 	I915_WRITE(D_STATE, dstate);
3159 }
3160 
3161 void i85x_init_clock_gating(struct drm_device *dev)
3162 {
3163 	struct drm_i915_private *dev_priv = dev->dev_private;
3164 
3165 	I915_WRITE(RENCLK_GATE_D1, SV_CLOCK_GATE_DISABLE);
3166 }
3167 
3168 void i830_init_clock_gating(struct drm_device *dev)
3169 {
3170 	struct drm_i915_private *dev_priv = dev->dev_private;
3171 
3172 	I915_WRITE(DSPCLK_GATE_D, OVRUNIT_CLOCK_GATE_DISABLE);
3173 }
3174 
3175 void ibx_init_clock_gating(struct drm_device *dev)
3176 {
3177 	struct drm_i915_private *dev_priv = dev->dev_private;
3178 
3179 	/*
3180 	 * On Ibex Peak and Cougar Point, we need to disable clock
3181 	 * gating for the panel power sequencer or it will fail to
3182 	 * start up when no ports are active.
3183 	 */
3184 	I915_WRITE(SOUTH_DSPCLK_GATE_D, PCH_DPLSUNIT_CLOCK_GATE_DISABLE);
3185 }
3186 
3187 static void ironlake_teardown_rc6(struct drm_device *dev)
3188 {
3189 	struct drm_i915_private *dev_priv = dev->dev_private;
3190 
3191 	if (dev_priv->renderctx) {
3192 		i915_gem_object_unpin(dev_priv->renderctx);
3193 		drm_gem_object_unreference(&dev_priv->renderctx->base);
3194 		dev_priv->renderctx = NULL;
3195 	}
3196 
3197 	if (dev_priv->pwrctx) {
3198 		i915_gem_object_unpin(dev_priv->pwrctx);
3199 		drm_gem_object_unreference(&dev_priv->pwrctx->base);
3200 		dev_priv->pwrctx = NULL;
3201 	}
3202 }
3203 
3204 void ironlake_disable_rc6(struct drm_device *dev)
3205 {
3206 	struct drm_i915_private *dev_priv = dev->dev_private;
3207 
3208 	if (I915_READ(PWRCTXA)) {
3209 		/* Wake the GPU, prevent RC6, then restore RSTDBYCTL */
3210 		I915_WRITE(RSTDBYCTL, I915_READ(RSTDBYCTL) | RCX_SW_EXIT);
3211 		(void)_intel_wait_for(dev,
3212 		    ((I915_READ(RSTDBYCTL) & RSX_STATUS_MASK) == RSX_STATUS_ON),
3213 		    50, 1, "915pro");
3214 
3215 		I915_WRITE(PWRCTXA, 0);
3216 		POSTING_READ(PWRCTXA);
3217 
3218 		I915_WRITE(RSTDBYCTL, I915_READ(RSTDBYCTL) & ~RCX_SW_EXIT);
3219 		POSTING_READ(RSTDBYCTL);
3220 	}
3221 
3222 	ironlake_teardown_rc6(dev);
3223 }
3224 
3225 static int ironlake_setup_rc6(struct drm_device *dev)
3226 {
3227 	struct drm_i915_private *dev_priv = dev->dev_private;
3228 
3229 	if (dev_priv->renderctx == NULL)
3230 		dev_priv->renderctx = intel_alloc_context_page(dev);
3231 	if (!dev_priv->renderctx)
3232 		return -ENOMEM;
3233 
3234 	if (dev_priv->pwrctx == NULL)
3235 		dev_priv->pwrctx = intel_alloc_context_page(dev);
3236 	if (!dev_priv->pwrctx) {
3237 		ironlake_teardown_rc6(dev);
3238 		return -ENOMEM;
3239 	}
3240 
3241 	return 0;
3242 }
3243 
3244 void ironlake_enable_rc6(struct drm_device *dev)
3245 {
3246 	struct drm_i915_private *dev_priv = dev->dev_private;
3247 	int ret;
3248 
3249 	/* rc6 disabled by default due to repeated reports of hanging during
3250 	 * boot and resume.
3251 	 */
3252 	if (!intel_enable_rc6(dev))
3253 		return;
3254 
3255 	DRM_LOCK(dev);
3256 	ret = ironlake_setup_rc6(dev);
3257 	if (ret) {
3258 		DRM_UNLOCK(dev);
3259 		return;
3260 	}
3261 
3262 	/*
3263 	 * GPU can automatically power down the render unit if given a page
3264 	 * to save state.
3265 	 */
3266 	ret = BEGIN_LP_RING(6);
3267 	if (ret) {
3268 		ironlake_teardown_rc6(dev);
3269 		DRM_UNLOCK(dev);
3270 		return;
3271 	}
3272 
3273 	OUT_RING(MI_SUSPEND_FLUSH | MI_SUSPEND_FLUSH_EN);
3274 	OUT_RING(MI_SET_CONTEXT);
3275 	OUT_RING(dev_priv->renderctx->gtt_offset |
3276 		 MI_MM_SPACE_GTT |
3277 		 MI_SAVE_EXT_STATE_EN |
3278 		 MI_RESTORE_EXT_STATE_EN |
3279 		 MI_RESTORE_INHIBIT);
3280 	OUT_RING(MI_SUSPEND_FLUSH);
3281 	OUT_RING(MI_NOOP);
3282 	OUT_RING(MI_FLUSH);
3283 	ADVANCE_LP_RING();
3284 
3285 	/*
3286 	 * Wait for the command parser to advance past MI_SET_CONTEXT. The HW
3287 	 * does an implicit flush, combined with MI_FLUSH above, it should be
3288 	 * safe to assume that renderctx is valid
3289 	 */
3290 	ret = intel_wait_ring_idle(LP_RING(dev_priv));
3291 	if (ret) {
3292 		DRM_ERROR("failed to enable ironlake power savings\n");
3293 		ironlake_teardown_rc6(dev);
3294 		DRM_UNLOCK(dev);
3295 		return;
3296 	}
3297 
3298 	I915_WRITE(PWRCTXA, dev_priv->pwrctx->gtt_offset | PWRCTX_EN);
3299 	I915_WRITE(RSTDBYCTL, I915_READ(RSTDBYCTL) & ~RCX_SW_EXIT);
3300 	DRM_UNLOCK(dev);
3301 }
3302 
3303 void intel_init_clock_gating(struct drm_device *dev)
3304 {
3305 	struct drm_i915_private *dev_priv = dev->dev_private;
3306 
3307 	dev_priv->display.init_clock_gating(dev);
3308 
3309 	if (dev_priv->display.init_pch_clock_gating)
3310 		dev_priv->display.init_pch_clock_gating(dev);
3311 }
3312