1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2020 Intel Corporation
4  */
5 
6 #include <linux/string_helpers.h>
7 #include <linux/kernel.h>
8 
9 #include <drm/drm_print.h>
10 
11 #include "i915_drv.h"
12 #include "i915_reg.h"
13 #include "i915_trace.h"
14 #include "i915_utils.h"
15 #include "intel_pm.h"
16 #include "vlv_suspend.h"
17 
18 #include "gt/intel_gt_regs.h"
19 
20 struct vlv_s0ix_state {
21 	/* GAM */
22 	u32 wr_watermark;
23 	u32 gfx_prio_ctrl;
24 	u32 arb_mode;
25 	u32 gfx_pend_tlb0;
26 	u32 gfx_pend_tlb1;
27 	u32 lra_limits[GEN7_LRA_LIMITS_REG_NUM];
28 	u32 media_max_req_count;
29 	u32 gfx_max_req_count;
30 	u32 render_hwsp;
31 	u32 ecochk;
32 	u32 bsd_hwsp;
33 	u32 blt_hwsp;
34 	u32 tlb_rd_addr;
35 
36 	/* MBC */
37 	u32 g3dctl;
38 	u32 gsckgctl;
39 	u32 mbctl;
40 
41 	/* GCP */
42 	u32 ucgctl1;
43 	u32 ucgctl3;
44 	u32 rcgctl1;
45 	u32 rcgctl2;
46 	u32 rstctl;
47 	u32 misccpctl;
48 
49 	/* GPM */
50 	u32 gfxpause;
51 	u32 rpdeuhwtc;
52 	u32 rpdeuc;
53 	u32 ecobus;
54 	u32 pwrdwnupctl;
55 	u32 rp_down_timeout;
56 	u32 rp_deucsw;
57 	u32 rcubmabdtmr;
58 	u32 rcedata;
59 	u32 spare2gh;
60 
61 	/* Display 1 CZ domain */
62 	u32 gt_imr;
63 	u32 gt_ier;
64 	u32 pm_imr;
65 	u32 pm_ier;
66 	u32 gt_scratch[GEN7_GT_SCRATCH_REG_NUM];
67 
68 	/* GT SA CZ domain */
69 	u32 tilectl;
70 	u32 gt_fifoctl;
71 	u32 gtlc_wake_ctrl;
72 	u32 gtlc_survive;
73 	u32 pmwgicz;
74 
75 	/* Display 2 CZ domain */
76 	u32 gu_ctl0;
77 	u32 gu_ctl1;
78 	u32 pcbr;
79 	u32 clock_gate_dis2;
80 };
81 
82 /*
83  * Save all Gunit registers that may be lost after a D3 and a subsequent
84  * S0i[R123] transition. The list of registers needing a save/restore is
85  * defined in the VLV2_S0IXRegs document. This documents marks all Gunit
86  * registers in the following way:
87  * - Driver: saved/restored by the driver
88  * - Punit : saved/restored by the Punit firmware
89  * - No, w/o marking: no need to save/restore, since the register is R/O or
90  *                    used internally by the HW in a way that doesn't depend
91  *                    keeping the content across a suspend/resume.
92  * - Debug : used for debugging
93  *
94  * We save/restore all registers marked with 'Driver', with the following
95  * exceptions:
96  * - Registers out of use, including also registers marked with 'Debug'.
97  *   These have no effect on the driver's operation, so we don't save/restore
98  *   them to reduce the overhead.
99  * - Registers that are fully setup by an initialization function called from
100  *   the resume path. For example many clock gating and RPS/RC6 registers.
101  * - Registers that provide the right functionality with their reset defaults.
102  *
103  * TODO: Except for registers that based on the above 3 criteria can be safely
104  * ignored, we save/restore all others, practically treating the HW context as
105  * a black-box for the driver. Further investigation is needed to reduce the
106  * saved/restored registers even further, by following the same 3 criteria.
107  */
vlv_save_gunit_s0ix_state(struct drm_i915_private * i915)108 static void vlv_save_gunit_s0ix_state(struct drm_i915_private *i915)
109 {
110 	struct vlv_s0ix_state *s = i915->vlv_s0ix_state;
111 	struct intel_uncore *uncore = &i915->uncore;
112 	int i;
113 
114 	if (!s)
115 		return;
116 
117 	/* GAM 0x4000-0x4770 */
118 	s->wr_watermark = intel_uncore_read(uncore, GEN7_WR_WATERMARK);
119 	s->gfx_prio_ctrl = intel_uncore_read(uncore, GEN7_GFX_PRIO_CTRL);
120 	s->arb_mode = intel_uncore_read(uncore, ARB_MODE);
121 	s->gfx_pend_tlb0 = intel_uncore_read(uncore, GEN7_GFX_PEND_TLB0);
122 	s->gfx_pend_tlb1 = intel_uncore_read(uncore, GEN7_GFX_PEND_TLB1);
123 
124 	for (i = 0; i < ARRAY_SIZE(s->lra_limits); i++)
125 		s->lra_limits[i] = intel_uncore_read(uncore, GEN7_LRA_LIMITS(i));
126 
127 	s->media_max_req_count = intel_uncore_read(uncore, GEN7_MEDIA_MAX_REQ_COUNT);
128 	s->gfx_max_req_count = intel_uncore_read(uncore, GEN7_GFX_MAX_REQ_COUNT);
129 
130 	s->render_hwsp = intel_uncore_read(uncore, RENDER_HWS_PGA_GEN7);
131 	s->ecochk = intel_uncore_read(uncore, GAM_ECOCHK);
132 	s->bsd_hwsp = intel_uncore_read(uncore, BSD_HWS_PGA_GEN7);
133 	s->blt_hwsp = intel_uncore_read(uncore, BLT_HWS_PGA_GEN7);
134 
135 	s->tlb_rd_addr = intel_uncore_read(uncore, GEN7_TLB_RD_ADDR);
136 
137 	/* MBC 0x9024-0x91D0, 0x8500 */
138 	s->g3dctl = intel_uncore_read(uncore, VLV_G3DCTL);
139 	s->gsckgctl = intel_uncore_read(uncore, VLV_GSCKGCTL);
140 	s->mbctl = intel_uncore_read(uncore, GEN6_MBCTL);
141 
142 	/* GCP 0x9400-0x9424, 0x8100-0x810C */
143 	s->ucgctl1 = intel_uncore_read(uncore, GEN6_UCGCTL1);
144 	s->ucgctl3 = intel_uncore_read(uncore, GEN6_UCGCTL3);
145 	s->rcgctl1 = intel_uncore_read(uncore, GEN6_RCGCTL1);
146 	s->rcgctl2 = intel_uncore_read(uncore, GEN6_RCGCTL2);
147 	s->rstctl = intel_uncore_read(uncore, GEN6_RSTCTL);
148 	s->misccpctl = intel_uncore_read(uncore, GEN7_MISCCPCTL);
149 
150 	/* GPM 0xA000-0xAA84, 0x8000-0x80FC */
151 	s->gfxpause = intel_uncore_read(uncore, GEN6_GFXPAUSE);
152 	s->rpdeuhwtc = intel_uncore_read(uncore, GEN6_RPDEUHWTC);
153 	s->rpdeuc = intel_uncore_read(uncore, GEN6_RPDEUC);
154 	s->ecobus = intel_uncore_read(uncore, ECOBUS);
155 	s->pwrdwnupctl = intel_uncore_read(uncore, VLV_PWRDWNUPCTL);
156 	s->rp_down_timeout = intel_uncore_read(uncore, GEN6_RP_DOWN_TIMEOUT);
157 	s->rp_deucsw = intel_uncore_read(uncore, GEN6_RPDEUCSW);
158 	s->rcubmabdtmr = intel_uncore_read(uncore, GEN6_RCUBMABDTMR);
159 	s->rcedata = intel_uncore_read(uncore, VLV_RCEDATA);
160 	s->spare2gh = intel_uncore_read(uncore, VLV_SPAREG2H);
161 
162 	/* Display CZ domain, 0x4400C-0x4402C, 0x4F000-0x4F11F */
163 	s->gt_imr = intel_uncore_read(uncore, GTIMR);
164 	s->gt_ier = intel_uncore_read(uncore, GTIER);
165 	s->pm_imr = intel_uncore_read(uncore, GEN6_PMIMR);
166 	s->pm_ier = intel_uncore_read(uncore, GEN6_PMIER);
167 
168 	for (i = 0; i < ARRAY_SIZE(s->gt_scratch); i++)
169 		s->gt_scratch[i] = intel_uncore_read(uncore, GEN7_GT_SCRATCH(i));
170 
171 	/* GT SA CZ domain, 0x100000-0x138124 */
172 	s->tilectl = intel_uncore_read(uncore, TILECTL);
173 	s->gt_fifoctl = intel_uncore_read(uncore, GTFIFOCTL);
174 	s->gtlc_wake_ctrl = intel_uncore_read(uncore, VLV_GTLC_WAKE_CTRL);
175 	s->gtlc_survive = intel_uncore_read(uncore, VLV_GTLC_SURVIVABILITY_REG);
176 	s->pmwgicz = intel_uncore_read(uncore, VLV_PMWGICZ);
177 
178 	/* Gunit-Display CZ domain, 0x182028-0x1821CF */
179 	s->gu_ctl0 = intel_uncore_read(uncore, VLV_GU_CTL0);
180 	s->gu_ctl1 = intel_uncore_read(uncore, VLV_GU_CTL1);
181 	s->pcbr = intel_uncore_read(uncore, VLV_PCBR);
182 	s->clock_gate_dis2 = intel_uncore_read(uncore, VLV_GUNIT_CLOCK_GATE2);
183 
184 	/*
185 	 * Not saving any of:
186 	 * DFT,		0x9800-0x9EC0
187 	 * SARB,	0xB000-0xB1FC
188 	 * GAC,		0x5208-0x524C, 0x14000-0x14C000
189 	 * PCI CFG
190 	 */
191 }
192 
vlv_restore_gunit_s0ix_state(struct drm_i915_private * i915)193 static void vlv_restore_gunit_s0ix_state(struct drm_i915_private *i915)
194 {
195 	struct vlv_s0ix_state *s = i915->vlv_s0ix_state;
196 	struct intel_uncore *uncore = &i915->uncore;
197 	u32 val;
198 	int i;
199 
200 	if (!s)
201 		return;
202 
203 	/* GAM 0x4000-0x4770 */
204 	intel_uncore_write(uncore, GEN7_WR_WATERMARK, s->wr_watermark);
205 	intel_uncore_write(uncore, GEN7_GFX_PRIO_CTRL, s->gfx_prio_ctrl);
206 	intel_uncore_write(uncore, ARB_MODE, s->arb_mode | (0xffff << 16));
207 	intel_uncore_write(uncore, GEN7_GFX_PEND_TLB0, s->gfx_pend_tlb0);
208 	intel_uncore_write(uncore, GEN7_GFX_PEND_TLB1, s->gfx_pend_tlb1);
209 
210 	for (i = 0; i < ARRAY_SIZE(s->lra_limits); i++)
211 		intel_uncore_write(uncore, GEN7_LRA_LIMITS(i), s->lra_limits[i]);
212 
213 	intel_uncore_write(uncore, GEN7_MEDIA_MAX_REQ_COUNT, s->media_max_req_count);
214 	intel_uncore_write(uncore, GEN7_GFX_MAX_REQ_COUNT, s->gfx_max_req_count);
215 
216 	intel_uncore_write(uncore, RENDER_HWS_PGA_GEN7, s->render_hwsp);
217 	intel_uncore_write(uncore, GAM_ECOCHK, s->ecochk);
218 	intel_uncore_write(uncore, BSD_HWS_PGA_GEN7, s->bsd_hwsp);
219 	intel_uncore_write(uncore, BLT_HWS_PGA_GEN7, s->blt_hwsp);
220 
221 	intel_uncore_write(uncore, GEN7_TLB_RD_ADDR, s->tlb_rd_addr);
222 
223 	/* MBC 0x9024-0x91D0, 0x8500 */
224 	intel_uncore_write(uncore, VLV_G3DCTL, s->g3dctl);
225 	intel_uncore_write(uncore, VLV_GSCKGCTL, s->gsckgctl);
226 	intel_uncore_write(uncore, GEN6_MBCTL, s->mbctl);
227 
228 	/* GCP 0x9400-0x9424, 0x8100-0x810C */
229 	intel_uncore_write(uncore, GEN6_UCGCTL1, s->ucgctl1);
230 	intel_uncore_write(uncore, GEN6_UCGCTL3, s->ucgctl3);
231 	intel_uncore_write(uncore, GEN6_RCGCTL1, s->rcgctl1);
232 	intel_uncore_write(uncore, GEN6_RCGCTL2, s->rcgctl2);
233 	intel_uncore_write(uncore, GEN6_RSTCTL, s->rstctl);
234 	intel_uncore_write(uncore, GEN7_MISCCPCTL, s->misccpctl);
235 
236 	/* GPM 0xA000-0xAA84, 0x8000-0x80FC */
237 	intel_uncore_write(uncore, GEN6_GFXPAUSE, s->gfxpause);
238 	intel_uncore_write(uncore, GEN6_RPDEUHWTC, s->rpdeuhwtc);
239 	intel_uncore_write(uncore, GEN6_RPDEUC, s->rpdeuc);
240 	intel_uncore_write(uncore, ECOBUS, s->ecobus);
241 	intel_uncore_write(uncore, VLV_PWRDWNUPCTL, s->pwrdwnupctl);
242 	intel_uncore_write(uncore, GEN6_RP_DOWN_TIMEOUT, s->rp_down_timeout);
243 	intel_uncore_write(uncore, GEN6_RPDEUCSW, s->rp_deucsw);
244 	intel_uncore_write(uncore, GEN6_RCUBMABDTMR, s->rcubmabdtmr);
245 	intel_uncore_write(uncore, VLV_RCEDATA, s->rcedata);
246 	intel_uncore_write(uncore, VLV_SPAREG2H, s->spare2gh);
247 
248 	/* Display CZ domain, 0x4400C-0x4402C, 0x4F000-0x4F11F */
249 	intel_uncore_write(uncore, GTIMR, s->gt_imr);
250 	intel_uncore_write(uncore, GTIER, s->gt_ier);
251 	intel_uncore_write(uncore, GEN6_PMIMR, s->pm_imr);
252 	intel_uncore_write(uncore, GEN6_PMIER, s->pm_ier);
253 
254 	for (i = 0; i < ARRAY_SIZE(s->gt_scratch); i++)
255 		intel_uncore_write(uncore, GEN7_GT_SCRATCH(i), s->gt_scratch[i]);
256 
257 	/* GT SA CZ domain, 0x100000-0x138124 */
258 	intel_uncore_write(uncore, TILECTL, s->tilectl);
259 	intel_uncore_write(uncore, GTFIFOCTL, s->gt_fifoctl);
260 	/*
261 	 * Preserve the GT allow wake and GFX force clock bit, they are not
262 	 * be restored, as they are used to control the s0ix suspend/resume
263 	 * sequence by the caller.
264 	 */
265 	val = intel_uncore_read(uncore, VLV_GTLC_WAKE_CTRL);
266 	val &= VLV_GTLC_ALLOWWAKEREQ;
267 	val |= s->gtlc_wake_ctrl & ~VLV_GTLC_ALLOWWAKEREQ;
268 	intel_uncore_write(uncore, VLV_GTLC_WAKE_CTRL, val);
269 
270 	val = intel_uncore_read(uncore, VLV_GTLC_SURVIVABILITY_REG);
271 	val &= VLV_GFX_CLK_FORCE_ON_BIT;
272 	val |= s->gtlc_survive & ~VLV_GFX_CLK_FORCE_ON_BIT;
273 	intel_uncore_write(uncore, VLV_GTLC_SURVIVABILITY_REG, val);
274 
275 	intel_uncore_write(uncore, VLV_PMWGICZ, s->pmwgicz);
276 
277 	/* Gunit-Display CZ domain, 0x182028-0x1821CF */
278 	intel_uncore_write(uncore, VLV_GU_CTL0, s->gu_ctl0);
279 	intel_uncore_write(uncore, VLV_GU_CTL1, s->gu_ctl1);
280 	intel_uncore_write(uncore, VLV_PCBR, s->pcbr);
281 	intel_uncore_write(uncore, VLV_GUNIT_CLOCK_GATE2, s->clock_gate_dis2);
282 }
283 
vlv_wait_for_pw_status(struct drm_i915_private * i915,u32 mask,u32 val)284 static int vlv_wait_for_pw_status(struct drm_i915_private *i915,
285 				  u32 mask, u32 val)
286 {
287 	i915_reg_t reg = VLV_GTLC_PW_STATUS;
288 	u32 reg_value;
289 	int ret;
290 
291 	/* The HW does not like us polling for PW_STATUS frequently, so
292 	 * use the sleeping loop rather than risk the busy spin within
293 	 * intel_wait_for_register().
294 	 *
295 	 * Transitioning between RC6 states should be at most 2ms (see
296 	 * valleyview_enable_rps) so use a 3ms timeout.
297 	 */
298 	ret = wait_for(((reg_value =
299 			 intel_uncore_read_notrace(&i915->uncore, reg)) & mask)
300 		       == val, 3);
301 
302 	/* just trace the final value */
303 	trace_i915_reg_rw(false, reg, reg_value, sizeof(reg_value), true);
304 
305 	return ret;
306 }
307 
vlv_force_gfx_clock(struct drm_i915_private * i915,bool force_on)308 static int vlv_force_gfx_clock(struct drm_i915_private *i915, bool force_on)
309 {
310 	struct intel_uncore *uncore = &i915->uncore;
311 	u32 val;
312 	int err;
313 
314 	val = intel_uncore_read(uncore, VLV_GTLC_SURVIVABILITY_REG);
315 	val &= ~VLV_GFX_CLK_FORCE_ON_BIT;
316 	if (force_on)
317 		val |= VLV_GFX_CLK_FORCE_ON_BIT;
318 	intel_uncore_write(uncore, VLV_GTLC_SURVIVABILITY_REG, val);
319 
320 	if (!force_on)
321 		return 0;
322 
323 	err = intel_wait_for_register(uncore,
324 				      VLV_GTLC_SURVIVABILITY_REG,
325 				      VLV_GFX_CLK_STATUS_BIT,
326 				      VLV_GFX_CLK_STATUS_BIT,
327 				      20);
328 	if (err)
329 		drm_err(&i915->drm,
330 			"timeout waiting for GFX clock force-on (%08x)\n",
331 			intel_uncore_read(uncore, VLV_GTLC_SURVIVABILITY_REG));
332 
333 	return err;
334 }
335 
vlv_allow_gt_wake(struct drm_i915_private * i915,bool allow)336 static int vlv_allow_gt_wake(struct drm_i915_private *i915, bool allow)
337 {
338 	struct intel_uncore *uncore = &i915->uncore;
339 	u32 mask;
340 	u32 val;
341 	int err;
342 
343 	val = intel_uncore_read(uncore, VLV_GTLC_WAKE_CTRL);
344 	val &= ~VLV_GTLC_ALLOWWAKEREQ;
345 	if (allow)
346 		val |= VLV_GTLC_ALLOWWAKEREQ;
347 	intel_uncore_write(uncore, VLV_GTLC_WAKE_CTRL, val);
348 	intel_uncore_posting_read(uncore, VLV_GTLC_WAKE_CTRL);
349 
350 	mask = VLV_GTLC_ALLOWWAKEACK;
351 	val = allow ? mask : 0;
352 
353 	err = vlv_wait_for_pw_status(i915, mask, val);
354 	if (err)
355 		drm_err(&i915->drm, "timeout disabling GT waking\n");
356 
357 	return err;
358 }
359 
vlv_wait_for_gt_wells(struct drm_i915_private * dev_priv,bool wait_for_on)360 static void vlv_wait_for_gt_wells(struct drm_i915_private *dev_priv,
361 				  bool wait_for_on)
362 {
363 	u32 mask;
364 	u32 val;
365 
366 	mask = VLV_GTLC_PW_MEDIA_STATUS_MASK | VLV_GTLC_PW_RENDER_STATUS_MASK;
367 	val = wait_for_on ? mask : 0;
368 
369 	/*
370 	 * RC6 transitioning can be delayed up to 2 msec (see
371 	 * valleyview_enable_rps), use 3 msec for safety.
372 	 *
373 	 * This can fail to turn off the rc6 if the GPU is stuck after a failed
374 	 * reset and we are trying to force the machine to sleep.
375 	 */
376 	if (vlv_wait_for_pw_status(dev_priv, mask, val))
377 		drm_dbg(&dev_priv->drm,
378 			"timeout waiting for GT wells to go %s\n",
379 			str_on_off(wait_for_on));
380 }
381 
vlv_check_no_gt_access(struct drm_i915_private * i915)382 static void vlv_check_no_gt_access(struct drm_i915_private *i915)
383 {
384 	struct intel_uncore *uncore = &i915->uncore;
385 
386 	if (!(intel_uncore_read(uncore, VLV_GTLC_PW_STATUS) & VLV_GTLC_ALLOWWAKEERR))
387 		return;
388 
389 	drm_dbg(&i915->drm, "GT register access while GT waking disabled\n");
390 	intel_uncore_write(uncore, VLV_GTLC_PW_STATUS, VLV_GTLC_ALLOWWAKEERR);
391 }
392 
vlv_suspend_complete(struct drm_i915_private * dev_priv)393 int vlv_suspend_complete(struct drm_i915_private *dev_priv)
394 {
395 	u32 mask;
396 	int err;
397 
398 	if (!IS_VALLEYVIEW(dev_priv) && !IS_CHERRYVIEW(dev_priv))
399 		return 0;
400 
401 	/*
402 	 * Bspec defines the following GT well on flags as debug only, so
403 	 * don't treat them as hard failures.
404 	 */
405 	vlv_wait_for_gt_wells(dev_priv, false);
406 
407 	mask = VLV_GTLC_RENDER_CTX_EXISTS | VLV_GTLC_MEDIA_CTX_EXISTS;
408 	drm_WARN_ON(&dev_priv->drm,
409 		    (intel_uncore_read(&dev_priv->uncore, VLV_GTLC_WAKE_CTRL) & mask) != mask);
410 
411 	vlv_check_no_gt_access(dev_priv);
412 
413 	err = vlv_force_gfx_clock(dev_priv, true);
414 	if (err)
415 		goto err1;
416 
417 	err = vlv_allow_gt_wake(dev_priv, false);
418 	if (err)
419 		goto err2;
420 
421 	vlv_save_gunit_s0ix_state(dev_priv);
422 
423 	err = vlv_force_gfx_clock(dev_priv, false);
424 	if (err)
425 		goto err2;
426 
427 	return 0;
428 
429 err2:
430 	/* For safety always re-enable waking and disable gfx clock forcing */
431 	vlv_allow_gt_wake(dev_priv, true);
432 err1:
433 	vlv_force_gfx_clock(dev_priv, false);
434 
435 	return err;
436 }
437 
vlv_resume_prepare(struct drm_i915_private * dev_priv,bool rpm_resume)438 int vlv_resume_prepare(struct drm_i915_private *dev_priv, bool rpm_resume)
439 {
440 	int err;
441 	int ret;
442 
443 	if (!IS_VALLEYVIEW(dev_priv) && !IS_CHERRYVIEW(dev_priv))
444 		return 0;
445 
446 	/*
447 	 * If any of the steps fail just try to continue, that's the best we
448 	 * can do at this point. Return the first error code (which will also
449 	 * leave RPM permanently disabled).
450 	 */
451 	ret = vlv_force_gfx_clock(dev_priv, true);
452 
453 	vlv_restore_gunit_s0ix_state(dev_priv);
454 
455 	err = vlv_allow_gt_wake(dev_priv, true);
456 	if (!ret)
457 		ret = err;
458 
459 	err = vlv_force_gfx_clock(dev_priv, false);
460 	if (!ret)
461 		ret = err;
462 
463 	vlv_check_no_gt_access(dev_priv);
464 
465 	if (rpm_resume)
466 		intel_init_clock_gating(dev_priv);
467 
468 	return ret;
469 }
470 
vlv_suspend_init(struct drm_i915_private * i915)471 int vlv_suspend_init(struct drm_i915_private *i915)
472 {
473 	if (!IS_VALLEYVIEW(i915))
474 		return 0;
475 
476 	/* we write all the values in the struct, so no need to zero it out */
477 	i915->vlv_s0ix_state = kmalloc(sizeof(*i915->vlv_s0ix_state),
478 				       GFP_KERNEL);
479 	if (!i915->vlv_s0ix_state)
480 		return -ENOMEM;
481 
482 	return 0;
483 }
484 
vlv_suspend_cleanup(struct drm_i915_private * i915)485 void vlv_suspend_cleanup(struct drm_i915_private *i915)
486 {
487 	if (!i915->vlv_s0ix_state)
488 		return;
489 
490 	kfree(i915->vlv_s0ix_state);
491 	i915->vlv_s0ix_state = NULL;
492 }
493