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drm/i915: Delay the release of the forcewake by a jiffie
[~andy/linux] / drivers / gpu / drm / i915 / intel_uncore.c
1 /*
2  * Copyright © 2013 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
24 #include "i915_drv.h"
25 #include "intel_drv.h"
26
27 #define FORCEWAKE_ACK_TIMEOUT_MS 2
28
29 #define __raw_i915_read8(dev_priv__, reg__) readb((dev_priv__)->regs + (reg__))
30 #define __raw_i915_write8(dev_priv__, reg__, val__) writeb(val__, (dev_priv__)->regs + (reg__))
31
32 #define __raw_i915_read16(dev_priv__, reg__) readw((dev_priv__)->regs + (reg__))
33 #define __raw_i915_write16(dev_priv__, reg__, val__) writew(val__, (dev_priv__)->regs + (reg__))
34
35 #define __raw_i915_read32(dev_priv__, reg__) readl((dev_priv__)->regs + (reg__))
36 #define __raw_i915_write32(dev_priv__, reg__, val__) writel(val__, (dev_priv__)->regs + (reg__))
37
38 #define __raw_i915_read64(dev_priv__, reg__) readq((dev_priv__)->regs + (reg__))
39 #define __raw_i915_write64(dev_priv__, reg__, val__) writeq(val__, (dev_priv__)->regs + (reg__))
40
41 #define __raw_posting_read(dev_priv__, reg__) (void)__raw_i915_read32(dev_priv__, reg__)
42
43
44 static void __gen6_gt_wait_for_thread_c0(struct drm_i915_private *dev_priv)
45 {
46         u32 gt_thread_status_mask;
47
48         if (IS_HASWELL(dev_priv->dev))
49                 gt_thread_status_mask = GEN6_GT_THREAD_STATUS_CORE_MASK_HSW;
50         else
51                 gt_thread_status_mask = GEN6_GT_THREAD_STATUS_CORE_MASK;
52
53         /* w/a for a sporadic read returning 0 by waiting for the GT
54          * thread to wake up.
55          */
56         if (wait_for_atomic_us((__raw_i915_read32(dev_priv, GEN6_GT_THREAD_STATUS_REG) & gt_thread_status_mask) == 0, 500))
57                 DRM_ERROR("GT thread status wait timed out\n");
58 }
59
60 static void __gen6_gt_force_wake_reset(struct drm_i915_private *dev_priv)
61 {
62         __raw_i915_write32(dev_priv, FORCEWAKE, 0);
63         /* something from same cacheline, but !FORCEWAKE */
64         __raw_posting_read(dev_priv, ECOBUS);
65 }
66
67 static void __gen6_gt_force_wake_get(struct drm_i915_private *dev_priv)
68 {
69         if (wait_for_atomic((__raw_i915_read32(dev_priv, FORCEWAKE_ACK) & 1) == 0,
70                             FORCEWAKE_ACK_TIMEOUT_MS))
71                 DRM_ERROR("Timed out waiting for forcewake old ack to clear.\n");
72
73         __raw_i915_write32(dev_priv, FORCEWAKE, 1);
74         /* something from same cacheline, but !FORCEWAKE */
75         __raw_posting_read(dev_priv, ECOBUS);
76
77         if (wait_for_atomic((__raw_i915_read32(dev_priv, FORCEWAKE_ACK) & 1),
78                             FORCEWAKE_ACK_TIMEOUT_MS))
79                 DRM_ERROR("Timed out waiting for forcewake to ack request.\n");
80
81         /* WaRsForcewakeWaitTC0:snb */
82         __gen6_gt_wait_for_thread_c0(dev_priv);
83 }
84
85 static void __gen6_gt_force_wake_mt_reset(struct drm_i915_private *dev_priv)
86 {
87         __raw_i915_write32(dev_priv, FORCEWAKE_MT, _MASKED_BIT_DISABLE(0xffff));
88         /* something from same cacheline, but !FORCEWAKE_MT */
89         __raw_posting_read(dev_priv, ECOBUS);
90 }
91
92 static void __gen6_gt_force_wake_mt_get(struct drm_i915_private *dev_priv)
93 {
94         u32 forcewake_ack;
95
96         if (IS_HASWELL(dev_priv->dev))
97                 forcewake_ack = FORCEWAKE_ACK_HSW;
98         else
99                 forcewake_ack = FORCEWAKE_MT_ACK;
100
101         if (wait_for_atomic((__raw_i915_read32(dev_priv, forcewake_ack) & FORCEWAKE_KERNEL) == 0,
102                             FORCEWAKE_ACK_TIMEOUT_MS))
103                 DRM_ERROR("Timed out waiting for forcewake old ack to clear.\n");
104
105         __raw_i915_write32(dev_priv, FORCEWAKE_MT,
106                            _MASKED_BIT_ENABLE(FORCEWAKE_KERNEL));
107         /* something from same cacheline, but !FORCEWAKE_MT */
108         __raw_posting_read(dev_priv, ECOBUS);
109
110         if (wait_for_atomic((__raw_i915_read32(dev_priv, forcewake_ack) & FORCEWAKE_KERNEL),
111                             FORCEWAKE_ACK_TIMEOUT_MS))
112                 DRM_ERROR("Timed out waiting for forcewake to ack request.\n");
113
114         /* WaRsForcewakeWaitTC0:ivb,hsw */
115         __gen6_gt_wait_for_thread_c0(dev_priv);
116 }
117
118 static void gen6_gt_check_fifodbg(struct drm_i915_private *dev_priv)
119 {
120         u32 gtfifodbg;
121
122         gtfifodbg = __raw_i915_read32(dev_priv, GTFIFODBG);
123         if (WARN(gtfifodbg & GT_FIFO_CPU_ERROR_MASK,
124              "MMIO read or write has been dropped %x\n", gtfifodbg))
125                 __raw_i915_write32(dev_priv, GTFIFODBG, GT_FIFO_CPU_ERROR_MASK);
126 }
127
128 static void __gen6_gt_force_wake_put(struct drm_i915_private *dev_priv)
129 {
130         __raw_i915_write32(dev_priv, FORCEWAKE, 0);
131         /* something from same cacheline, but !FORCEWAKE */
132         __raw_posting_read(dev_priv, ECOBUS);
133         gen6_gt_check_fifodbg(dev_priv);
134 }
135
136 static void __gen6_gt_force_wake_mt_put(struct drm_i915_private *dev_priv)
137 {
138         __raw_i915_write32(dev_priv, FORCEWAKE_MT,
139                            _MASKED_BIT_DISABLE(FORCEWAKE_KERNEL));
140         /* something from same cacheline, but !FORCEWAKE_MT */
141         __raw_posting_read(dev_priv, ECOBUS);
142         gen6_gt_check_fifodbg(dev_priv);
143 }
144
145 static int __gen6_gt_wait_for_fifo(struct drm_i915_private *dev_priv)
146 {
147         int ret = 0;
148
149         if (dev_priv->uncore.fifo_count < GT_FIFO_NUM_RESERVED_ENTRIES) {
150                 int loop = 500;
151                 u32 fifo = __raw_i915_read32(dev_priv, GT_FIFO_FREE_ENTRIES);
152                 while (fifo <= GT_FIFO_NUM_RESERVED_ENTRIES && loop--) {
153                         udelay(10);
154                         fifo = __raw_i915_read32(dev_priv, GT_FIFO_FREE_ENTRIES);
155                 }
156                 if (WARN_ON(loop < 0 && fifo <= GT_FIFO_NUM_RESERVED_ENTRIES))
157                         ++ret;
158                 dev_priv->uncore.fifo_count = fifo;
159         }
160         dev_priv->uncore.fifo_count--;
161
162         return ret;
163 }
164
165 static void vlv_force_wake_reset(struct drm_i915_private *dev_priv)
166 {
167         __raw_i915_write32(dev_priv, FORCEWAKE_VLV,
168                            _MASKED_BIT_DISABLE(0xffff));
169         /* something from same cacheline, but !FORCEWAKE_VLV */
170         __raw_posting_read(dev_priv, FORCEWAKE_ACK_VLV);
171 }
172
173 static void vlv_force_wake_get(struct drm_i915_private *dev_priv)
174 {
175         if (wait_for_atomic((__raw_i915_read32(dev_priv, FORCEWAKE_ACK_VLV) & FORCEWAKE_KERNEL) == 0,
176                             FORCEWAKE_ACK_TIMEOUT_MS))
177                 DRM_ERROR("Timed out waiting for forcewake old ack to clear.\n");
178
179         __raw_i915_write32(dev_priv, FORCEWAKE_VLV,
180                            _MASKED_BIT_ENABLE(FORCEWAKE_KERNEL));
181         __raw_i915_write32(dev_priv, FORCEWAKE_MEDIA_VLV,
182                            _MASKED_BIT_ENABLE(FORCEWAKE_KERNEL));
183
184         if (wait_for_atomic((__raw_i915_read32(dev_priv, FORCEWAKE_ACK_VLV) & FORCEWAKE_KERNEL),
185                             FORCEWAKE_ACK_TIMEOUT_MS))
186                 DRM_ERROR("Timed out waiting for GT to ack forcewake request.\n");
187
188         if (wait_for_atomic((__raw_i915_read32(dev_priv, FORCEWAKE_ACK_MEDIA_VLV) &
189                              FORCEWAKE_KERNEL),
190                             FORCEWAKE_ACK_TIMEOUT_MS))
191                 DRM_ERROR("Timed out waiting for media to ack forcewake request.\n");
192
193         /* WaRsForcewakeWaitTC0:vlv */
194         __gen6_gt_wait_for_thread_c0(dev_priv);
195 }
196
197 static void vlv_force_wake_put(struct drm_i915_private *dev_priv)
198 {
199         __raw_i915_write32(dev_priv, FORCEWAKE_VLV,
200                            _MASKED_BIT_DISABLE(FORCEWAKE_KERNEL));
201         __raw_i915_write32(dev_priv, FORCEWAKE_MEDIA_VLV,
202                            _MASKED_BIT_DISABLE(FORCEWAKE_KERNEL));
203         /* The below doubles as a POSTING_READ */
204         gen6_gt_check_fifodbg(dev_priv);
205 }
206
207 static void gen6_force_wake_work(struct work_struct *work)
208 {
209         struct drm_i915_private *dev_priv =
210                 container_of(work, typeof(*dev_priv), uncore.force_wake_work.work);
211         unsigned long irqflags;
212
213         spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
214         if (--dev_priv->uncore.forcewake_count == 0)
215                 dev_priv->uncore.funcs.force_wake_put(dev_priv);
216         spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
217 }
218
219 void intel_uncore_early_sanitize(struct drm_device *dev)
220 {
221         struct drm_i915_private *dev_priv = dev->dev_private;
222
223         if (HAS_FPGA_DBG_UNCLAIMED(dev))
224                 __raw_i915_write32(dev_priv, FPGA_DBG, FPGA_DBG_RM_NOCLAIM);
225 }
226
227 void intel_uncore_init(struct drm_device *dev)
228 {
229         struct drm_i915_private *dev_priv = dev->dev_private;
230
231         INIT_DELAYED_WORK(&dev_priv->uncore.force_wake_work,
232                           gen6_force_wake_work);
233
234         if (IS_VALLEYVIEW(dev)) {
235                 dev_priv->uncore.funcs.force_wake_get = vlv_force_wake_get;
236                 dev_priv->uncore.funcs.force_wake_put = vlv_force_wake_put;
237         } else if (IS_HASWELL(dev)) {
238                 dev_priv->uncore.funcs.force_wake_get = __gen6_gt_force_wake_mt_get;
239                 dev_priv->uncore.funcs.force_wake_put = __gen6_gt_force_wake_mt_put;
240         } else if (IS_IVYBRIDGE(dev)) {
241                 u32 ecobus;
242
243                 /* IVB configs may use multi-threaded forcewake */
244
245                 /* A small trick here - if the bios hasn't configured
246                  * MT forcewake, and if the device is in RC6, then
247                  * force_wake_mt_get will not wake the device and the
248                  * ECOBUS read will return zero. Which will be
249                  * (correctly) interpreted by the test below as MT
250                  * forcewake being disabled.
251                  */
252                 mutex_lock(&dev->struct_mutex);
253                 __gen6_gt_force_wake_mt_get(dev_priv);
254                 ecobus = __raw_i915_read32(dev_priv, ECOBUS);
255                 __gen6_gt_force_wake_mt_put(dev_priv);
256                 mutex_unlock(&dev->struct_mutex);
257
258                 if (ecobus & FORCEWAKE_MT_ENABLE) {
259                         dev_priv->uncore.funcs.force_wake_get =
260                                 __gen6_gt_force_wake_mt_get;
261                         dev_priv->uncore.funcs.force_wake_put =
262                                 __gen6_gt_force_wake_mt_put;
263                 } else {
264                         DRM_INFO("No MT forcewake available on Ivybridge, this can result in issues\n");
265                         DRM_INFO("when using vblank-synced partial screen updates.\n");
266                         dev_priv->uncore.funcs.force_wake_get =
267                                 __gen6_gt_force_wake_get;
268                         dev_priv->uncore.funcs.force_wake_put =
269                                 __gen6_gt_force_wake_put;
270                 }
271         } else if (IS_GEN6(dev)) {
272                 dev_priv->uncore.funcs.force_wake_get =
273                         __gen6_gt_force_wake_get;
274                 dev_priv->uncore.funcs.force_wake_put =
275                         __gen6_gt_force_wake_put;
276         }
277 }
278
279 void intel_uncore_fini(struct drm_device *dev)
280 {
281         struct drm_i915_private *dev_priv = dev->dev_private;
282
283         flush_delayed_work(&dev_priv->uncore.force_wake_work);
284
285         /* Paranoia: make sure we have disabled everything before we exit. */
286         intel_uncore_sanitize(dev);
287 }
288
289 static void intel_uncore_forcewake_reset(struct drm_device *dev)
290 {
291         struct drm_i915_private *dev_priv = dev->dev_private;
292
293         if (IS_VALLEYVIEW(dev)) {
294                 vlv_force_wake_reset(dev_priv);
295         } else if (INTEL_INFO(dev)->gen >= 6) {
296                 __gen6_gt_force_wake_reset(dev_priv);
297                 if (IS_IVYBRIDGE(dev) || IS_HASWELL(dev))
298                         __gen6_gt_force_wake_mt_reset(dev_priv);
299         }
300 }
301
302 void intel_uncore_sanitize(struct drm_device *dev)
303 {
304         intel_uncore_forcewake_reset(dev);
305
306         /* BIOS often leaves RC6 enabled, but disable it for hw init */
307         intel_disable_gt_powersave(dev);
308 }
309
310 /*
311  * Generally this is called implicitly by the register read function. However,
312  * if some sequence requires the GT to not power down then this function should
313  * be called at the beginning of the sequence followed by a call to
314  * gen6_gt_force_wake_put() at the end of the sequence.
315  */
316 void gen6_gt_force_wake_get(struct drm_i915_private *dev_priv)
317 {
318         unsigned long irqflags;
319
320         spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
321         if (dev_priv->uncore.forcewake_count++ == 0)
322                 dev_priv->uncore.funcs.force_wake_get(dev_priv);
323         spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
324 }
325
326 /*
327  * see gen6_gt_force_wake_get()
328  */
329 void gen6_gt_force_wake_put(struct drm_i915_private *dev_priv)
330 {
331         unsigned long irqflags;
332
333         spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
334         if (--dev_priv->uncore.forcewake_count == 0) {
335                 dev_priv->uncore.forcewake_count++;
336                 mod_delayed_work(dev_priv->wq,
337                                  &dev_priv->uncore.force_wake_work,
338                                  1);
339         }
340         spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
341 }
342
343 /* We give fast paths for the really cool registers */
344 #define NEEDS_FORCE_WAKE(dev_priv, reg) \
345         ((HAS_FORCE_WAKE((dev_priv)->dev)) && \
346          ((reg) < 0x40000) &&            \
347          ((reg) != FORCEWAKE))
348
349 static void
350 ilk_dummy_write(struct drm_i915_private *dev_priv)
351 {
352         /* WaIssueDummyWriteToWakeupFromRC6:ilk Issue a dummy write to wake up
353          * the chip from rc6 before touching it for real. MI_MODE is masked,
354          * hence harmless to write 0 into. */
355         __raw_i915_write32(dev_priv, MI_MODE, 0);
356 }
357
358 static void
359 hsw_unclaimed_reg_clear(struct drm_i915_private *dev_priv, u32 reg)
360 {
361         if (HAS_FPGA_DBG_UNCLAIMED(dev_priv->dev) &&
362             (__raw_i915_read32(dev_priv, FPGA_DBG) & FPGA_DBG_RM_NOCLAIM)) {
363                 DRM_ERROR("Unknown unclaimed register before writing to %x\n",
364                           reg);
365                 __raw_i915_write32(dev_priv, FPGA_DBG, FPGA_DBG_RM_NOCLAIM);
366         }
367 }
368
369 static void
370 hsw_unclaimed_reg_check(struct drm_i915_private *dev_priv, u32 reg)
371 {
372         if (HAS_FPGA_DBG_UNCLAIMED(dev_priv->dev) &&
373             (__raw_i915_read32(dev_priv, FPGA_DBG) & FPGA_DBG_RM_NOCLAIM)) {
374                 DRM_ERROR("Unclaimed write to %x\n", reg);
375                 __raw_i915_write32(dev_priv, FPGA_DBG, FPGA_DBG_RM_NOCLAIM);
376         }
377 }
378
379 #define __i915_read(x) \
380 u##x i915_read##x(struct drm_i915_private *dev_priv, u32 reg, bool trace) { \
381         unsigned long irqflags; \
382         u##x val = 0; \
383         spin_lock_irqsave(&dev_priv->uncore.lock, irqflags); \
384         if (dev_priv->info->gen == 5) \
385                 ilk_dummy_write(dev_priv); \
386         if (NEEDS_FORCE_WAKE((dev_priv), (reg))) { \
387                 if (dev_priv->uncore.forcewake_count == 0) \
388                         dev_priv->uncore.funcs.force_wake_get(dev_priv); \
389                 val = __raw_i915_read##x(dev_priv, reg); \
390                 if (dev_priv->uncore.forcewake_count == 0) \
391                         dev_priv->uncore.funcs.force_wake_put(dev_priv); \
392         } else { \
393                 val = __raw_i915_read##x(dev_priv, reg); \
394         } \
395         spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags); \
396         trace_i915_reg_rw(false, reg, val, sizeof(val), trace); \
397         return val; \
398 }
399
400 __i915_read(8)
401 __i915_read(16)
402 __i915_read(32)
403 __i915_read(64)
404 #undef __i915_read
405
406 #define __i915_write(x) \
407 void i915_write##x(struct drm_i915_private *dev_priv, u32 reg, u##x val, bool trace) { \
408         unsigned long irqflags; \
409         u32 __fifo_ret = 0; \
410         trace_i915_reg_rw(true, reg, val, sizeof(val), trace); \
411         spin_lock_irqsave(&dev_priv->uncore.lock, irqflags); \
412         if (NEEDS_FORCE_WAKE((dev_priv), (reg))) { \
413                 __fifo_ret = __gen6_gt_wait_for_fifo(dev_priv); \
414         } \
415         if (dev_priv->info->gen == 5) \
416                 ilk_dummy_write(dev_priv); \
417         hsw_unclaimed_reg_clear(dev_priv, reg); \
418         __raw_i915_write##x(dev_priv, reg, val); \
419         if (unlikely(__fifo_ret)) { \
420                 gen6_gt_check_fifodbg(dev_priv); \
421         } \
422         hsw_unclaimed_reg_check(dev_priv, reg); \
423         spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags); \
424 }
425 __i915_write(8)
426 __i915_write(16)
427 __i915_write(32)
428 __i915_write(64)
429 #undef __i915_write
430
431 static const struct register_whitelist {
432         uint64_t offset;
433         uint32_t size;
434         uint32_t gen_bitmask; /* support gens, 0x10 for 4, 0x30 for 4 and 5, etc. */
435 } whitelist[] = {
436         { RING_TIMESTAMP(RENDER_RING_BASE), 8, 0xF0 },
437 };
438
439 int i915_reg_read_ioctl(struct drm_device *dev,
440                         void *data, struct drm_file *file)
441 {
442         struct drm_i915_private *dev_priv = dev->dev_private;
443         struct drm_i915_reg_read *reg = data;
444         struct register_whitelist const *entry = whitelist;
445         int i;
446
447         for (i = 0; i < ARRAY_SIZE(whitelist); i++, entry++) {
448                 if (entry->offset == reg->offset &&
449                     (1 << INTEL_INFO(dev)->gen & entry->gen_bitmask))
450                         break;
451         }
452
453         if (i == ARRAY_SIZE(whitelist))
454                 return -EINVAL;
455
456         switch (entry->size) {
457         case 8:
458                 reg->val = I915_READ64(reg->offset);
459                 break;
460         case 4:
461                 reg->val = I915_READ(reg->offset);
462                 break;
463         case 2:
464                 reg->val = I915_READ16(reg->offset);
465                 break;
466         case 1:
467                 reg->val = I915_READ8(reg->offset);
468                 break;
469         default:
470                 WARN_ON(1);
471                 return -EINVAL;
472         }
473
474         return 0;
475 }
476
477 static int i8xx_do_reset(struct drm_device *dev)
478 {
479         struct drm_i915_private *dev_priv = dev->dev_private;
480
481         if (IS_I85X(dev))
482                 return -ENODEV;
483
484         I915_WRITE(D_STATE, I915_READ(D_STATE) | DSTATE_GFX_RESET_I830);
485         POSTING_READ(D_STATE);
486
487         if (IS_I830(dev) || IS_845G(dev)) {
488                 I915_WRITE(DEBUG_RESET_I830,
489                            DEBUG_RESET_DISPLAY |
490                            DEBUG_RESET_RENDER |
491                            DEBUG_RESET_FULL);
492                 POSTING_READ(DEBUG_RESET_I830);
493                 msleep(1);
494
495                 I915_WRITE(DEBUG_RESET_I830, 0);
496                 POSTING_READ(DEBUG_RESET_I830);
497         }
498
499         msleep(1);
500
501         I915_WRITE(D_STATE, I915_READ(D_STATE) & ~DSTATE_GFX_RESET_I830);
502         POSTING_READ(D_STATE);
503
504         return 0;
505 }
506
507 static int i965_reset_complete(struct drm_device *dev)
508 {
509         u8 gdrst;
510         pci_read_config_byte(dev->pdev, I965_GDRST, &gdrst);
511         return (gdrst & GRDOM_RESET_ENABLE) == 0;
512 }
513
514 static int i965_do_reset(struct drm_device *dev)
515 {
516         int ret;
517
518         /*
519          * Set the domains we want to reset (GRDOM/bits 2 and 3) as
520          * well as the reset bit (GR/bit 0).  Setting the GR bit
521          * triggers the reset; when done, the hardware will clear it.
522          */
523         pci_write_config_byte(dev->pdev, I965_GDRST,
524                               GRDOM_RENDER | GRDOM_RESET_ENABLE);
525         ret =  wait_for(i965_reset_complete(dev), 500);
526         if (ret)
527                 return ret;
528
529         /* We can't reset render&media without also resetting display ... */
530         pci_write_config_byte(dev->pdev, I965_GDRST,
531                               GRDOM_MEDIA | GRDOM_RESET_ENABLE);
532
533         ret =  wait_for(i965_reset_complete(dev), 500);
534         if (ret)
535                 return ret;
536
537         pci_write_config_byte(dev->pdev, I965_GDRST, 0);
538
539         return 0;
540 }
541
542 static int ironlake_do_reset(struct drm_device *dev)
543 {
544         struct drm_i915_private *dev_priv = dev->dev_private;
545         u32 gdrst;
546         int ret;
547
548         gdrst = I915_READ(MCHBAR_MIRROR_BASE + ILK_GDSR);
549         gdrst &= ~GRDOM_MASK;
550         I915_WRITE(MCHBAR_MIRROR_BASE + ILK_GDSR,
551                    gdrst | GRDOM_RENDER | GRDOM_RESET_ENABLE);
552         ret = wait_for(I915_READ(MCHBAR_MIRROR_BASE + ILK_GDSR) & 0x1, 500);
553         if (ret)
554                 return ret;
555
556         /* We can't reset render&media without also resetting display ... */
557         gdrst = I915_READ(MCHBAR_MIRROR_BASE + ILK_GDSR);
558         gdrst &= ~GRDOM_MASK;
559         I915_WRITE(MCHBAR_MIRROR_BASE + ILK_GDSR,
560                    gdrst | GRDOM_MEDIA | GRDOM_RESET_ENABLE);
561         return wait_for(I915_READ(MCHBAR_MIRROR_BASE + ILK_GDSR) & 0x1, 500);
562 }
563
564 static int gen6_do_reset(struct drm_device *dev)
565 {
566         struct drm_i915_private *dev_priv = dev->dev_private;
567         int     ret;
568         unsigned long irqflags;
569
570         /* Hold uncore.lock across reset to prevent any register access
571          * with forcewake not set correctly
572          */
573         spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
574
575         /* Reset the chip */
576
577         /* GEN6_GDRST is not in the gt power well, no need to check
578          * for fifo space for the write or forcewake the chip for
579          * the read
580          */
581         __raw_i915_write32(dev_priv, GEN6_GDRST, GEN6_GRDOM_FULL);
582
583         /* Spin waiting for the device to ack the reset request */
584         ret = wait_for((__raw_i915_read32(dev_priv, GEN6_GDRST) & GEN6_GRDOM_FULL) == 0, 500);
585
586         intel_uncore_forcewake_reset(dev);
587
588         /* If reset with a user forcewake, try to restore, otherwise turn it off */
589         if (dev_priv->uncore.forcewake_count)
590                 dev_priv->uncore.funcs.force_wake_get(dev_priv);
591         else
592                 dev_priv->uncore.funcs.force_wake_put(dev_priv);
593
594         /* Restore fifo count */
595         dev_priv->uncore.fifo_count = __raw_i915_read32(dev_priv, GT_FIFO_FREE_ENTRIES);
596
597         spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
598         return ret;
599 }
600
601 int intel_gpu_reset(struct drm_device *dev)
602 {
603         switch (INTEL_INFO(dev)->gen) {
604         case 7:
605         case 6: return gen6_do_reset(dev);
606         case 5: return ironlake_do_reset(dev);
607         case 4: return i965_do_reset(dev);
608         case 2: return i8xx_do_reset(dev);
609         default: return -ENODEV;
610         }
611 }
612
613 void intel_uncore_clear_errors(struct drm_device *dev)
614 {
615         struct drm_i915_private *dev_priv = dev->dev_private;
616
617         /* XXX needs spinlock around caller's grouping */
618         if (HAS_FPGA_DBG_UNCLAIMED(dev))
619                 __raw_i915_write32(dev_priv, FPGA_DBG, FPGA_DBG_RM_NOCLAIM);
620 }
621
622 void intel_uncore_check_errors(struct drm_device *dev)
623 {
624         struct drm_i915_private *dev_priv = dev->dev_private;
625
626         if (HAS_FPGA_DBG_UNCLAIMED(dev) &&
627             (__raw_i915_read32(dev_priv, FPGA_DBG) & FPGA_DBG_RM_NOCLAIM)) {
628                 DRM_ERROR("Unclaimed register before interrupt\n");
629                 __raw_i915_write32(dev_priv, FPGA_DBG, FPGA_DBG_RM_NOCLAIM);
630         }
631 }