drm/gma500: Remove dead code
[platform/adaptation/renesas_rcar/renesas_kernel.git] / drivers / gpu / drm / gma500 / psb_irq.c
1 /**************************************************************************
2  * Copyright (c) 2007, Intel Corporation.
3  * All Rights Reserved.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms and conditions of the GNU General Public License,
7  * version 2, as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  *
14  * You should have received a copy of the GNU General Public License along with
15  * this program; if not, write to the Free Software Foundation, Inc.,
16  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
17  *
18  * Intel funded Tungsten Graphics (http://www.tungstengraphics.com) to
19  * develop this driver.
20  *
21  **************************************************************************/
22 /*
23  */
24
25 #include <drm/drmP.h>
26 #include "psb_drv.h"
27 #include "psb_reg.h"
28 #include "psb_intel_reg.h"
29 #include "power.h"
30 #include "psb_irq.h"
31 #include "mdfld_output.h"
32
33 /*
34  * inline functions
35  */
36
37 static inline u32
38 psb_pipestat(int pipe)
39 {
40         if (pipe == 0)
41                 return PIPEASTAT;
42         if (pipe == 1)
43                 return PIPEBSTAT;
44         if (pipe == 2)
45                 return PIPECSTAT;
46         BUG();
47 }
48
49 static inline u32
50 mid_pipe_event(int pipe)
51 {
52         if (pipe == 0)
53                 return _PSB_PIPEA_EVENT_FLAG;
54         if (pipe == 1)
55                 return _MDFLD_PIPEB_EVENT_FLAG;
56         if (pipe == 2)
57                 return _MDFLD_PIPEC_EVENT_FLAG;
58         BUG();
59 }
60
61 static inline u32
62 mid_pipe_vsync(int pipe)
63 {
64         if (pipe == 0)
65                 return _PSB_VSYNC_PIPEA_FLAG;
66         if (pipe == 1)
67                 return _PSB_VSYNC_PIPEB_FLAG;
68         if (pipe == 2)
69                 return _MDFLD_PIPEC_VBLANK_FLAG;
70         BUG();
71 }
72
73 static inline u32
74 mid_pipeconf(int pipe)
75 {
76         if (pipe == 0)
77                 return PIPEACONF;
78         if (pipe == 1)
79                 return PIPEBCONF;
80         if (pipe == 2)
81                 return PIPECCONF;
82         BUG();
83 }
84
85 void
86 psb_enable_pipestat(struct drm_psb_private *dev_priv, int pipe, u32 mask)
87 {
88         if ((dev_priv->pipestat[pipe] & mask) != mask) {
89                 u32 reg = psb_pipestat(pipe);
90                 dev_priv->pipestat[pipe] |= mask;
91                 /* Enable the interrupt, clear any pending status */
92                 if (gma_power_begin(dev_priv->dev, false)) {
93                         u32 writeVal = PSB_RVDC32(reg);
94                         writeVal |= (mask | (mask >> 16));
95                         PSB_WVDC32(writeVal, reg);
96                         (void) PSB_RVDC32(reg);
97                         gma_power_end(dev_priv->dev);
98                 }
99         }
100 }
101
102 void
103 psb_disable_pipestat(struct drm_psb_private *dev_priv, int pipe, u32 mask)
104 {
105         if ((dev_priv->pipestat[pipe] & mask) != 0) {
106                 u32 reg = psb_pipestat(pipe);
107                 dev_priv->pipestat[pipe] &= ~mask;
108                 if (gma_power_begin(dev_priv->dev, false)) {
109                         u32 writeVal = PSB_RVDC32(reg);
110                         writeVal &= ~mask;
111                         PSB_WVDC32(writeVal, reg);
112                         (void) PSB_RVDC32(reg);
113                         gma_power_end(dev_priv->dev);
114                 }
115         }
116 }
117
118 static void mid_enable_pipe_event(struct drm_psb_private *dev_priv, int pipe)
119 {
120         if (gma_power_begin(dev_priv->dev, false)) {
121                 u32 pipe_event = mid_pipe_event(pipe);
122                 dev_priv->vdc_irq_mask |= pipe_event;
123                 PSB_WVDC32(~dev_priv->vdc_irq_mask, PSB_INT_MASK_R);
124                 PSB_WVDC32(dev_priv->vdc_irq_mask, PSB_INT_ENABLE_R);
125                 gma_power_end(dev_priv->dev);
126         }
127 }
128
129 static void mid_disable_pipe_event(struct drm_psb_private *dev_priv, int pipe)
130 {
131         if (dev_priv->pipestat[pipe] == 0) {
132                 if (gma_power_begin(dev_priv->dev, false)) {
133                         u32 pipe_event = mid_pipe_event(pipe);
134                         dev_priv->vdc_irq_mask &= ~pipe_event;
135                         PSB_WVDC32(~dev_priv->vdc_irq_mask, PSB_INT_MASK_R);
136                         PSB_WVDC32(dev_priv->vdc_irq_mask, PSB_INT_ENABLE_R);
137                         gma_power_end(dev_priv->dev);
138                 }
139         }
140 }
141
142 /**
143  * Display controller interrupt handler for pipe event.
144  *
145  */
146 static void mid_pipe_event_handler(struct drm_device *dev, int pipe)
147 {
148         struct drm_psb_private *dev_priv =
149             (struct drm_psb_private *) dev->dev_private;
150
151         uint32_t pipe_stat_val = 0;
152         uint32_t pipe_stat_reg = psb_pipestat(pipe);
153         uint32_t pipe_enable = dev_priv->pipestat[pipe];
154         uint32_t pipe_status = dev_priv->pipestat[pipe] >> 16;
155         uint32_t pipe_clear;
156         uint32_t i = 0;
157
158         spin_lock(&dev_priv->irqmask_lock);
159
160         pipe_stat_val = PSB_RVDC32(pipe_stat_reg);
161         pipe_stat_val &= pipe_enable | pipe_status;
162         pipe_stat_val &= pipe_stat_val >> 16;
163
164         spin_unlock(&dev_priv->irqmask_lock);
165
166         /* Clear the 2nd level interrupt status bits
167          * Sometimes the bits are very sticky so we repeat until they unstick */
168         for (i = 0; i < 0xffff; i++) {
169                 PSB_WVDC32(PSB_RVDC32(pipe_stat_reg), pipe_stat_reg);
170                 pipe_clear = PSB_RVDC32(pipe_stat_reg) & pipe_status;
171
172                 if (pipe_clear == 0)
173                         break;
174         }
175
176         if (pipe_clear)
177                 dev_err(dev->dev,
178                 "%s, can't clear status bits for pipe %d, its value = 0x%x.\n",
179                 __func__, pipe, PSB_RVDC32(pipe_stat_reg));
180
181         if (pipe_stat_val & PIPE_VBLANK_STATUS)
182                 drm_handle_vblank(dev, pipe);
183
184         if (pipe_stat_val & PIPE_TE_STATUS)
185                 drm_handle_vblank(dev, pipe);
186 }
187
188 /*
189  * Display controller interrupt handler.
190  */
191 static void psb_vdc_interrupt(struct drm_device *dev, uint32_t vdc_stat)
192 {
193         if (vdc_stat & _PSB_IRQ_ASLE)
194                 psb_intel_opregion_asle_intr(dev);
195
196         if (vdc_stat & _PSB_VSYNC_PIPEA_FLAG)
197                 mid_pipe_event_handler(dev, 0);
198
199         if (vdc_stat & _PSB_VSYNC_PIPEB_FLAG)
200                 mid_pipe_event_handler(dev, 1);
201 }
202
203 irqreturn_t psb_irq_handler(int irq, void *arg)
204 {
205         struct drm_device *dev = arg;
206         struct drm_psb_private *dev_priv = dev->dev_private;
207         uint32_t vdc_stat, dsp_int = 0, sgx_int = 0, hotplug_int = 0;
208         int handled = 0;
209
210         spin_lock(&dev_priv->irqmask_lock);
211
212         vdc_stat = PSB_RVDC32(PSB_INT_IDENTITY_R);
213
214         if (vdc_stat & (_PSB_PIPE_EVENT_FLAG|_PSB_IRQ_ASLE))
215                 dsp_int = 1;
216
217         /* FIXME: Handle Medfield
218         if (vdc_stat & _MDFLD_DISP_ALL_IRQ_FLAG)
219                 dsp_int = 1;
220         */
221
222         if (vdc_stat & _PSB_IRQ_SGX_FLAG)
223                 sgx_int = 1;
224         if (vdc_stat & _PSB_IRQ_DISP_HOTSYNC)
225                 hotplug_int = 1;
226
227         vdc_stat &= dev_priv->vdc_irq_mask;
228         spin_unlock(&dev_priv->irqmask_lock);
229
230         if (dsp_int && gma_power_is_on(dev)) {
231                 psb_vdc_interrupt(dev, vdc_stat);
232                 handled = 1;
233         }
234
235         if (sgx_int) {
236                 /* Not expected - we have it masked, shut it up */
237                 u32 s, s2;
238                 s = PSB_RSGX32(PSB_CR_EVENT_STATUS);
239                 s2 = PSB_RSGX32(PSB_CR_EVENT_STATUS2);
240                 PSB_WSGX32(s, PSB_CR_EVENT_HOST_CLEAR);
241                 PSB_WSGX32(s2, PSB_CR_EVENT_HOST_CLEAR2);
242                 /* if s & _PSB_CE_TWOD_COMPLETE we have 2D done but
243                    we may as well poll even if we add that ! */
244                 handled = 1;
245         }
246
247         /* Note: this bit has other meanings on some devices, so we will
248            need to address that later if it ever matters */
249         if (hotplug_int && dev_priv->ops->hotplug) {
250                 handled = dev_priv->ops->hotplug(dev);
251                 REG_WRITE(PORT_HOTPLUG_STAT, REG_READ(PORT_HOTPLUG_STAT));
252         }
253
254         PSB_WVDC32(vdc_stat, PSB_INT_IDENTITY_R);
255         (void) PSB_RVDC32(PSB_INT_IDENTITY_R);
256         rmb();
257
258         if (!handled)
259                 return IRQ_NONE;
260
261         return IRQ_HANDLED;
262 }
263
264 void psb_irq_preinstall(struct drm_device *dev)
265 {
266         struct drm_psb_private *dev_priv =
267             (struct drm_psb_private *) dev->dev_private;
268         unsigned long irqflags;
269
270         spin_lock_irqsave(&dev_priv->irqmask_lock, irqflags);
271
272         if (gma_power_is_on(dev))
273                 PSB_WVDC32(0xFFFFFFFF, PSB_HWSTAM);
274         if (dev->vblank[0].enabled)
275                 dev_priv->vdc_irq_mask |= _PSB_VSYNC_PIPEA_FLAG;
276         if (dev->vblank[1].enabled)
277                 dev_priv->vdc_irq_mask |= _PSB_VSYNC_PIPEB_FLAG;
278
279         /* FIXME: Handle Medfield irq mask
280         if (dev->vblank[1].enabled)
281                 dev_priv->vdc_irq_mask |= _MDFLD_PIPEB_EVENT_FLAG;
282         if (dev->vblank[2].enabled)
283                 dev_priv->vdc_irq_mask |= _MDFLD_PIPEC_EVENT_FLAG;
284         */
285
286         /* Revisit this area - want per device masks ? */
287         if (dev_priv->ops->hotplug)
288                 dev_priv->vdc_irq_mask |= _PSB_IRQ_DISP_HOTSYNC;
289         dev_priv->vdc_irq_mask |= _PSB_IRQ_ASLE;
290
291         /* This register is safe even if display island is off */
292         PSB_WVDC32(~dev_priv->vdc_irq_mask, PSB_INT_MASK_R);
293         spin_unlock_irqrestore(&dev_priv->irqmask_lock, irqflags);
294 }
295
296 int psb_irq_postinstall(struct drm_device *dev)
297 {
298         struct drm_psb_private *dev_priv =
299             (struct drm_psb_private *) dev->dev_private;
300         unsigned long irqflags;
301
302         spin_lock_irqsave(&dev_priv->irqmask_lock, irqflags);
303
304         /* This register is safe even if display island is off */
305         PSB_WVDC32(dev_priv->vdc_irq_mask, PSB_INT_ENABLE_R);
306         PSB_WVDC32(0xFFFFFFFF, PSB_HWSTAM);
307
308         if (dev->vblank[0].enabled)
309                 psb_enable_pipestat(dev_priv, 0, PIPE_VBLANK_INTERRUPT_ENABLE);
310         else
311                 psb_disable_pipestat(dev_priv, 0, PIPE_VBLANK_INTERRUPT_ENABLE);
312
313         if (dev->vblank[1].enabled)
314                 psb_enable_pipestat(dev_priv, 1, PIPE_VBLANK_INTERRUPT_ENABLE);
315         else
316                 psb_disable_pipestat(dev_priv, 1, PIPE_VBLANK_INTERRUPT_ENABLE);
317
318         if (dev->vblank[2].enabled)
319                 psb_enable_pipestat(dev_priv, 2, PIPE_VBLANK_INTERRUPT_ENABLE);
320         else
321                 psb_disable_pipestat(dev_priv, 2, PIPE_VBLANK_INTERRUPT_ENABLE);
322
323         if (dev_priv->ops->hotplug_enable)
324                 dev_priv->ops->hotplug_enable(dev, true);
325
326         spin_unlock_irqrestore(&dev_priv->irqmask_lock, irqflags);
327         return 0;
328 }
329
330 void psb_irq_uninstall(struct drm_device *dev)
331 {
332         struct drm_psb_private *dev_priv = dev->dev_private;
333         unsigned long irqflags;
334
335         spin_lock_irqsave(&dev_priv->irqmask_lock, irqflags);
336
337         if (dev_priv->ops->hotplug_enable)
338                 dev_priv->ops->hotplug_enable(dev, false);
339
340         PSB_WVDC32(0xFFFFFFFF, PSB_HWSTAM);
341
342         if (dev->vblank[0].enabled)
343                 psb_disable_pipestat(dev_priv, 0, PIPE_VBLANK_INTERRUPT_ENABLE);
344
345         if (dev->vblank[1].enabled)
346                 psb_disable_pipestat(dev_priv, 1, PIPE_VBLANK_INTERRUPT_ENABLE);
347
348         if (dev->vblank[2].enabled)
349                 psb_disable_pipestat(dev_priv, 2, PIPE_VBLANK_INTERRUPT_ENABLE);
350
351         dev_priv->vdc_irq_mask &= _PSB_IRQ_SGX_FLAG |
352                                   _PSB_IRQ_MSVDX_FLAG |
353                                   _LNC_IRQ_TOPAZ_FLAG;
354
355         /* These two registers are safe even if display island is off */
356         PSB_WVDC32(~dev_priv->vdc_irq_mask, PSB_INT_MASK_R);
357         PSB_WVDC32(dev_priv->vdc_irq_mask, PSB_INT_ENABLE_R);
358
359         wmb();
360
361         /* This register is safe even if display island is off */
362         PSB_WVDC32(PSB_RVDC32(PSB_INT_IDENTITY_R), PSB_INT_IDENTITY_R);
363         spin_unlock_irqrestore(&dev_priv->irqmask_lock, irqflags);
364 }
365
366 void psb_irq_turn_on_dpst(struct drm_device *dev)
367 {
368         struct drm_psb_private *dev_priv =
369                 (struct drm_psb_private *) dev->dev_private;
370         u32 hist_reg;
371         u32 pwm_reg;
372
373         if (gma_power_begin(dev, false)) {
374                 PSB_WVDC32(1 << 31, HISTOGRAM_LOGIC_CONTROL);
375                 hist_reg = PSB_RVDC32(HISTOGRAM_LOGIC_CONTROL);
376                 PSB_WVDC32(1 << 31, HISTOGRAM_INT_CONTROL);
377                 hist_reg = PSB_RVDC32(HISTOGRAM_INT_CONTROL);
378
379                 PSB_WVDC32(0x80010100, PWM_CONTROL_LOGIC);
380                 pwm_reg = PSB_RVDC32(PWM_CONTROL_LOGIC);
381                 PSB_WVDC32(pwm_reg | PWM_PHASEIN_ENABLE
382                                                 | PWM_PHASEIN_INT_ENABLE,
383                                                            PWM_CONTROL_LOGIC);
384                 pwm_reg = PSB_RVDC32(PWM_CONTROL_LOGIC);
385
386                 psb_enable_pipestat(dev_priv, 0, PIPE_DPST_EVENT_ENABLE);
387
388                 hist_reg = PSB_RVDC32(HISTOGRAM_INT_CONTROL);
389                 PSB_WVDC32(hist_reg | HISTOGRAM_INT_CTRL_CLEAR,
390                                                         HISTOGRAM_INT_CONTROL);
391                 pwm_reg = PSB_RVDC32(PWM_CONTROL_LOGIC);
392                 PSB_WVDC32(pwm_reg | 0x80010100 | PWM_PHASEIN_ENABLE,
393                                                         PWM_CONTROL_LOGIC);
394
395                 gma_power_end(dev);
396         }
397 }
398
399 int psb_irq_enable_dpst(struct drm_device *dev)
400 {
401         struct drm_psb_private *dev_priv =
402                 (struct drm_psb_private *) dev->dev_private;
403         unsigned long irqflags;
404
405         spin_lock_irqsave(&dev_priv->irqmask_lock, irqflags);
406
407         /* enable DPST */
408         mid_enable_pipe_event(dev_priv, 0);
409         psb_irq_turn_on_dpst(dev);
410
411         spin_unlock_irqrestore(&dev_priv->irqmask_lock, irqflags);
412         return 0;
413 }
414
415 void psb_irq_turn_off_dpst(struct drm_device *dev)
416 {
417         struct drm_psb_private *dev_priv =
418             (struct drm_psb_private *) dev->dev_private;
419         u32 hist_reg;
420         u32 pwm_reg;
421
422         if (gma_power_begin(dev, false)) {
423                 PSB_WVDC32(0x00000000, HISTOGRAM_INT_CONTROL);
424                 hist_reg = PSB_RVDC32(HISTOGRAM_INT_CONTROL);
425
426                 psb_disable_pipestat(dev_priv, 0, PIPE_DPST_EVENT_ENABLE);
427
428                 pwm_reg = PSB_RVDC32(PWM_CONTROL_LOGIC);
429                 PSB_WVDC32(pwm_reg & ~PWM_PHASEIN_INT_ENABLE,
430                                                         PWM_CONTROL_LOGIC);
431                 pwm_reg = PSB_RVDC32(PWM_CONTROL_LOGIC);
432
433                 gma_power_end(dev);
434         }
435 }
436
437 int psb_irq_disable_dpst(struct drm_device *dev)
438 {
439         struct drm_psb_private *dev_priv =
440             (struct drm_psb_private *) dev->dev_private;
441         unsigned long irqflags;
442
443         spin_lock_irqsave(&dev_priv->irqmask_lock, irqflags);
444
445         mid_disable_pipe_event(dev_priv, 0);
446         psb_irq_turn_off_dpst(dev);
447
448         spin_unlock_irqrestore(&dev_priv->irqmask_lock, irqflags);
449
450         return 0;
451 }
452
453 /*
454  * It is used to enable VBLANK interrupt
455  */
456 int psb_enable_vblank(struct drm_device *dev, int pipe)
457 {
458         struct drm_psb_private *dev_priv = dev->dev_private;
459         unsigned long irqflags;
460         uint32_t reg_val = 0;
461         uint32_t pipeconf_reg = mid_pipeconf(pipe);
462
463         /* Medfield is different - we should perhaps extract out vblank
464            and blacklight etc ops */
465         if (IS_MFLD(dev))
466                 return mdfld_enable_te(dev, pipe);
467
468         if (gma_power_begin(dev, false)) {
469                 reg_val = REG_READ(pipeconf_reg);
470                 gma_power_end(dev);
471         }
472
473         if (!(reg_val & PIPEACONF_ENABLE))
474                 return -EINVAL;
475
476         spin_lock_irqsave(&dev_priv->irqmask_lock, irqflags);
477
478         if (pipe == 0)
479                 dev_priv->vdc_irq_mask |= _PSB_VSYNC_PIPEA_FLAG;
480         else if (pipe == 1)
481                 dev_priv->vdc_irq_mask |= _PSB_VSYNC_PIPEB_FLAG;
482
483         PSB_WVDC32(~dev_priv->vdc_irq_mask, PSB_INT_MASK_R);
484         PSB_WVDC32(dev_priv->vdc_irq_mask, PSB_INT_ENABLE_R);
485         psb_enable_pipestat(dev_priv, pipe, PIPE_VBLANK_INTERRUPT_ENABLE);
486
487         spin_unlock_irqrestore(&dev_priv->irqmask_lock, irqflags);
488
489         return 0;
490 }
491
492 /*
493  * It is used to disable VBLANK interrupt
494  */
495 void psb_disable_vblank(struct drm_device *dev, int pipe)
496 {
497         struct drm_psb_private *dev_priv = dev->dev_private;
498         unsigned long irqflags;
499
500         if (IS_MFLD(dev))
501                 mdfld_disable_te(dev, pipe);
502         spin_lock_irqsave(&dev_priv->irqmask_lock, irqflags);
503
504         if (pipe == 0)
505                 dev_priv->vdc_irq_mask &= ~_PSB_VSYNC_PIPEA_FLAG;
506         else if (pipe == 1)
507                 dev_priv->vdc_irq_mask &= ~_PSB_VSYNC_PIPEB_FLAG;
508
509         PSB_WVDC32(~dev_priv->vdc_irq_mask, PSB_INT_MASK_R);
510         PSB_WVDC32(dev_priv->vdc_irq_mask, PSB_INT_ENABLE_R);
511         psb_disable_pipestat(dev_priv, pipe, PIPE_VBLANK_INTERRUPT_ENABLE);
512
513         spin_unlock_irqrestore(&dev_priv->irqmask_lock, irqflags);
514 }
515
516 /*
517  * It is used to enable TE interrupt
518  */
519 int mdfld_enable_te(struct drm_device *dev, int pipe)
520 {
521         struct drm_psb_private *dev_priv =
522                 (struct drm_psb_private *) dev->dev_private;
523         unsigned long irqflags;
524         uint32_t reg_val = 0;
525         uint32_t pipeconf_reg = mid_pipeconf(pipe);
526
527         if (gma_power_begin(dev, false)) {
528                 reg_val = REG_READ(pipeconf_reg);
529                 gma_power_end(dev);
530         }
531
532         if (!(reg_val & PIPEACONF_ENABLE))
533                 return -EINVAL;
534
535         spin_lock_irqsave(&dev_priv->irqmask_lock, irqflags);
536
537         mid_enable_pipe_event(dev_priv, pipe);
538         psb_enable_pipestat(dev_priv, pipe, PIPE_TE_ENABLE);
539
540         spin_unlock_irqrestore(&dev_priv->irqmask_lock, irqflags);
541
542         return 0;
543 }
544
545 /*
546  * It is used to disable TE interrupt
547  */
548 void mdfld_disable_te(struct drm_device *dev, int pipe)
549 {
550         struct drm_psb_private *dev_priv =
551                 (struct drm_psb_private *) dev->dev_private;
552         unsigned long irqflags;
553
554         if (!dev_priv->dsr_enable)
555                 return;
556
557         spin_lock_irqsave(&dev_priv->irqmask_lock, irqflags);
558
559         mid_disable_pipe_event(dev_priv, pipe);
560         psb_disable_pipestat(dev_priv, pipe, PIPE_TE_ENABLE);
561
562         spin_unlock_irqrestore(&dev_priv->irqmask_lock, irqflags);
563 }
564
565 /* Called from drm generic code, passed a 'crtc', which
566  * we use as a pipe index
567  */
568 u32 psb_get_vblank_counter(struct drm_device *dev, int pipe)
569 {
570         uint32_t high_frame = PIPEAFRAMEHIGH;
571         uint32_t low_frame = PIPEAFRAMEPIXEL;
572         uint32_t pipeconf_reg = PIPEACONF;
573         uint32_t reg_val = 0;
574         uint32_t high1 = 0, high2 = 0, low = 0, count = 0;
575
576         switch (pipe) {
577         case 0:
578                 break;
579         case 1:
580                 high_frame = PIPEBFRAMEHIGH;
581                 low_frame = PIPEBFRAMEPIXEL;
582                 pipeconf_reg = PIPEBCONF;
583                 break;
584         case 2:
585                 high_frame = PIPECFRAMEHIGH;
586                 low_frame = PIPECFRAMEPIXEL;
587                 pipeconf_reg = PIPECCONF;
588                 break;
589         default:
590                 dev_err(dev->dev, "%s, invalid pipe.\n", __func__);
591                 return 0;
592         }
593
594         if (!gma_power_begin(dev, false))
595                 return 0;
596
597         reg_val = REG_READ(pipeconf_reg);
598
599         if (!(reg_val & PIPEACONF_ENABLE)) {
600                 dev_err(dev->dev, "trying to get vblank count for disabled pipe %d\n",
601                                                                 pipe);
602                 goto psb_get_vblank_counter_exit;
603         }
604
605         /*
606          * High & low register fields aren't synchronized, so make sure
607          * we get a low value that's stable across two reads of the high
608          * register.
609          */
610         do {
611                 high1 = ((REG_READ(high_frame) & PIPE_FRAME_HIGH_MASK) >>
612                          PIPE_FRAME_HIGH_SHIFT);
613                 low =  ((REG_READ(low_frame) & PIPE_FRAME_LOW_MASK) >>
614                         PIPE_FRAME_LOW_SHIFT);
615                 high2 = ((REG_READ(high_frame) & PIPE_FRAME_HIGH_MASK) >>
616                          PIPE_FRAME_HIGH_SHIFT);
617         } while (high1 != high2);
618
619         count = (high1 << 8) | low;
620
621 psb_get_vblank_counter_exit:
622
623         gma_power_end(dev);
624
625         return count;
626 }
627