xref: /openbmc/linux/drivers/gpu/drm/i915/vlv_suspend.c (revision 55fd7e02)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2020 Intel Corporation
4  */
5 
6 #include <linux/kernel.h>
7 
8 #include <drm/drm_print.h>
9 
10 #include "i915_drv.h"
11 #include "i915_reg.h"
12 #include "i915_trace.h"
13 #include "i915_utils.h"
14 #include "intel_pm.h"
15 #include "vlv_suspend.h"
16 
17 struct vlv_s0ix_state {
18 	/* GAM */
19 	u32 wr_watermark;
20 	u32 gfx_prio_ctrl;
21 	u32 arb_mode;
22 	u32 gfx_pend_tlb0;
23 	u32 gfx_pend_tlb1;
24 	u32 lra_limits[GEN7_LRA_LIMITS_REG_NUM];
25 	u32 media_max_req_count;
26 	u32 gfx_max_req_count;
27 	u32 render_hwsp;
28 	u32 ecochk;
29 	u32 bsd_hwsp;
30 	u32 blt_hwsp;
31 	u32 tlb_rd_addr;
32 
33 	/* MBC */
34 	u32 g3dctl;
35 	u32 gsckgctl;
36 	u32 mbctl;
37 
38 	/* GCP */
39 	u32 ucgctl1;
40 	u32 ucgctl3;
41 	u32 rcgctl1;
42 	u32 rcgctl2;
43 	u32 rstctl;
44 	u32 misccpctl;
45 
46 	/* GPM */
47 	u32 gfxpause;
48 	u32 rpdeuhwtc;
49 	u32 rpdeuc;
50 	u32 ecobus;
51 	u32 pwrdwnupctl;
52 	u32 rp_down_timeout;
53 	u32 rp_deucsw;
54 	u32 rcubmabdtmr;
55 	u32 rcedata;
56 	u32 spare2gh;
57 
58 	/* Display 1 CZ domain */
59 	u32 gt_imr;
60 	u32 gt_ier;
61 	u32 pm_imr;
62 	u32 pm_ier;
63 	u32 gt_scratch[GEN7_GT_SCRATCH_REG_NUM];
64 
65 	/* GT SA CZ domain */
66 	u32 tilectl;
67 	u32 gt_fifoctl;
68 	u32 gtlc_wake_ctrl;
69 	u32 gtlc_survive;
70 	u32 pmwgicz;
71 
72 	/* Display 2 CZ domain */
73 	u32 gu_ctl0;
74 	u32 gu_ctl1;
75 	u32 pcbr;
76 	u32 clock_gate_dis2;
77 };
78 
79 /*
80  * Save all Gunit registers that may be lost after a D3 and a subsequent
81  * S0i[R123] transition. The list of registers needing a save/restore is
82  * defined in the VLV2_S0IXRegs document. This documents marks all Gunit
83  * registers in the following way:
84  * - Driver: saved/restored by the driver
85  * - Punit : saved/restored by the Punit firmware
86  * - No, w/o marking: no need to save/restore, since the register is R/O or
87  *                    used internally by the HW in a way that doesn't depend
88  *                    keeping the content across a suspend/resume.
89  * - Debug : used for debugging
90  *
91  * We save/restore all registers marked with 'Driver', with the following
92  * exceptions:
93  * - Registers out of use, including also registers marked with 'Debug'.
94  *   These have no effect on the driver's operation, so we don't save/restore
95  *   them to reduce the overhead.
96  * - Registers that are fully setup by an initialization function called from
97  *   the resume path. For example many clock gating and RPS/RC6 registers.
98  * - Registers that provide the right functionality with their reset defaults.
99  *
100  * TODO: Except for registers that based on the above 3 criteria can be safely
101  * ignored, we save/restore all others, practically treating the HW context as
102  * a black-box for the driver. Further investigation is needed to reduce the
103  * saved/restored registers even further, by following the same 3 criteria.
104  */
105 static void vlv_save_gunit_s0ix_state(struct drm_i915_private *i915)
106 {
107 	struct vlv_s0ix_state *s = i915->vlv_s0ix_state;
108 	struct intel_uncore *uncore = &i915->uncore;
109 	int i;
110 
111 	if (!s)
112 		return;
113 
114 	/* GAM 0x4000-0x4770 */
115 	s->wr_watermark = intel_uncore_read(uncore, GEN7_WR_WATERMARK);
116 	s->gfx_prio_ctrl = intel_uncore_read(uncore, GEN7_GFX_PRIO_CTRL);
117 	s->arb_mode = intel_uncore_read(uncore, ARB_MODE);
118 	s->gfx_pend_tlb0 = intel_uncore_read(uncore, GEN7_GFX_PEND_TLB0);
119 	s->gfx_pend_tlb1 = intel_uncore_read(uncore, GEN7_GFX_PEND_TLB1);
120 
121 	for (i = 0; i < ARRAY_SIZE(s->lra_limits); i++)
122 		s->lra_limits[i] = intel_uncore_read(uncore, GEN7_LRA_LIMITS(i));
123 
124 	s->media_max_req_count = intel_uncore_read(uncore, GEN7_MEDIA_MAX_REQ_COUNT);
125 	s->gfx_max_req_count = intel_uncore_read(uncore, GEN7_GFX_MAX_REQ_COUNT);
126 
127 	s->render_hwsp = intel_uncore_read(uncore, RENDER_HWS_PGA_GEN7);
128 	s->ecochk = intel_uncore_read(uncore, GAM_ECOCHK);
129 	s->bsd_hwsp = intel_uncore_read(uncore, BSD_HWS_PGA_GEN7);
130 	s->blt_hwsp = intel_uncore_read(uncore, BLT_HWS_PGA_GEN7);
131 
132 	s->tlb_rd_addr = intel_uncore_read(uncore, GEN7_TLB_RD_ADDR);
133 
134 	/* MBC 0x9024-0x91D0, 0x8500 */
135 	s->g3dctl = intel_uncore_read(uncore, VLV_G3DCTL);
136 	s->gsckgctl = intel_uncore_read(uncore, VLV_GSCKGCTL);
137 	s->mbctl = intel_uncore_read(uncore, GEN6_MBCTL);
138 
139 	/* GCP 0x9400-0x9424, 0x8100-0x810C */
140 	s->ucgctl1 = intel_uncore_read(uncore, GEN6_UCGCTL1);
141 	s->ucgctl3 = intel_uncore_read(uncore, GEN6_UCGCTL3);
142 	s->rcgctl1 = intel_uncore_read(uncore, GEN6_RCGCTL1);
143 	s->rcgctl2 = intel_uncore_read(uncore, GEN6_RCGCTL2);
144 	s->rstctl = intel_uncore_read(uncore, GEN6_RSTCTL);
145 	s->misccpctl = intel_uncore_read(uncore, GEN7_MISCCPCTL);
146 
147 	/* GPM 0xA000-0xAA84, 0x8000-0x80FC */
148 	s->gfxpause = intel_uncore_read(uncore, GEN6_GFXPAUSE);
149 	s->rpdeuhwtc = intel_uncore_read(uncore, GEN6_RPDEUHWTC);
150 	s->rpdeuc = intel_uncore_read(uncore, GEN6_RPDEUC);
151 	s->ecobus = intel_uncore_read(uncore, ECOBUS);
152 	s->pwrdwnupctl = intel_uncore_read(uncore, VLV_PWRDWNUPCTL);
153 	s->rp_down_timeout = intel_uncore_read(uncore, GEN6_RP_DOWN_TIMEOUT);
154 	s->rp_deucsw = intel_uncore_read(uncore, GEN6_RPDEUCSW);
155 	s->rcubmabdtmr = intel_uncore_read(uncore, GEN6_RCUBMABDTMR);
156 	s->rcedata = intel_uncore_read(uncore, VLV_RCEDATA);
157 	s->spare2gh = intel_uncore_read(uncore, VLV_SPAREG2H);
158 
159 	/* Display CZ domain, 0x4400C-0x4402C, 0x4F000-0x4F11F */
160 	s->gt_imr = intel_uncore_read(uncore, GTIMR);
161 	s->gt_ier = intel_uncore_read(uncore, GTIER);
162 	s->pm_imr = intel_uncore_read(uncore, GEN6_PMIMR);
163 	s->pm_ier = intel_uncore_read(uncore, GEN6_PMIER);
164 
165 	for (i = 0; i < ARRAY_SIZE(s->gt_scratch); i++)
166 		s->gt_scratch[i] = intel_uncore_read(uncore, GEN7_GT_SCRATCH(i));
167 
168 	/* GT SA CZ domain, 0x100000-0x138124 */
169 	s->tilectl = intel_uncore_read(uncore, TILECTL);
170 	s->gt_fifoctl = intel_uncore_read(uncore, GTFIFOCTL);
171 	s->gtlc_wake_ctrl = intel_uncore_read(uncore, VLV_GTLC_WAKE_CTRL);
172 	s->gtlc_survive = intel_uncore_read(uncore, VLV_GTLC_SURVIVABILITY_REG);
173 	s->pmwgicz = intel_uncore_read(uncore, VLV_PMWGICZ);
174 
175 	/* Gunit-Display CZ domain, 0x182028-0x1821CF */
176 	s->gu_ctl0 = intel_uncore_read(uncore, VLV_GU_CTL0);
177 	s->gu_ctl1 = intel_uncore_read(uncore, VLV_GU_CTL1);
178 	s->pcbr = intel_uncore_read(uncore, VLV_PCBR);
179 	s->clock_gate_dis2 = intel_uncore_read(uncore, VLV_GUNIT_CLOCK_GATE2);
180 
181 	/*
182 	 * Not saving any of:
183 	 * DFT,		0x9800-0x9EC0
184 	 * SARB,	0xB000-0xB1FC
185 	 * GAC,		0x5208-0x524C, 0x14000-0x14C000
186 	 * PCI CFG
187 	 */
188 }
189 
190 static void vlv_restore_gunit_s0ix_state(struct drm_i915_private *i915)
191 {
192 	struct vlv_s0ix_state *s = i915->vlv_s0ix_state;
193 	struct intel_uncore *uncore = &i915->uncore;
194 	u32 val;
195 	int i;
196 
197 	if (!s)
198 		return;
199 
200 	/* GAM 0x4000-0x4770 */
201 	intel_uncore_write(uncore, GEN7_WR_WATERMARK, s->wr_watermark);
202 	intel_uncore_write(uncore, GEN7_GFX_PRIO_CTRL, s->gfx_prio_ctrl);
203 	intel_uncore_write(uncore, ARB_MODE, s->arb_mode | (0xffff << 16));
204 	intel_uncore_write(uncore, GEN7_GFX_PEND_TLB0, s->gfx_pend_tlb0);
205 	intel_uncore_write(uncore, GEN7_GFX_PEND_TLB1, s->gfx_pend_tlb1);
206 
207 	for (i = 0; i < ARRAY_SIZE(s->lra_limits); i++)
208 		intel_uncore_write(uncore, GEN7_LRA_LIMITS(i), s->lra_limits[i]);
209 
210 	intel_uncore_write(uncore, GEN7_MEDIA_MAX_REQ_COUNT, s->media_max_req_count);
211 	intel_uncore_write(uncore, GEN7_GFX_MAX_REQ_COUNT, s->gfx_max_req_count);
212 
213 	intel_uncore_write(uncore, RENDER_HWS_PGA_GEN7, s->render_hwsp);
214 	intel_uncore_write(uncore, GAM_ECOCHK, s->ecochk);
215 	intel_uncore_write(uncore, BSD_HWS_PGA_GEN7, s->bsd_hwsp);
216 	intel_uncore_write(uncore, BLT_HWS_PGA_GEN7, s->blt_hwsp);
217 
218 	intel_uncore_write(uncore, GEN7_TLB_RD_ADDR, s->tlb_rd_addr);
219 
220 	/* MBC 0x9024-0x91D0, 0x8500 */
221 	intel_uncore_write(uncore, VLV_G3DCTL, s->g3dctl);
222 	intel_uncore_write(uncore, VLV_GSCKGCTL, s->gsckgctl);
223 	intel_uncore_write(uncore, GEN6_MBCTL, s->mbctl);
224 
225 	/* GCP 0x9400-0x9424, 0x8100-0x810C */
226 	intel_uncore_write(uncore, GEN6_UCGCTL1, s->ucgctl1);
227 	intel_uncore_write(uncore, GEN6_UCGCTL3, s->ucgctl3);
228 	intel_uncore_write(uncore, GEN6_RCGCTL1, s->rcgctl1);
229 	intel_uncore_write(uncore, GEN6_RCGCTL2, s->rcgctl2);
230 	intel_uncore_write(uncore, GEN6_RSTCTL, s->rstctl);
231 	intel_uncore_write(uncore, GEN7_MISCCPCTL, s->misccpctl);
232 
233 	/* GPM 0xA000-0xAA84, 0x8000-0x80FC */
234 	intel_uncore_write(uncore, GEN6_GFXPAUSE, s->gfxpause);
235 	intel_uncore_write(uncore, GEN6_RPDEUHWTC, s->rpdeuhwtc);
236 	intel_uncore_write(uncore, GEN6_RPDEUC, s->rpdeuc);
237 	intel_uncore_write(uncore, ECOBUS, s->ecobus);
238 	intel_uncore_write(uncore, VLV_PWRDWNUPCTL, s->pwrdwnupctl);
239 	intel_uncore_write(uncore, GEN6_RP_DOWN_TIMEOUT, s->rp_down_timeout);
240 	intel_uncore_write(uncore, GEN6_RPDEUCSW, s->rp_deucsw);
241 	intel_uncore_write(uncore, GEN6_RCUBMABDTMR, s->rcubmabdtmr);
242 	intel_uncore_write(uncore, VLV_RCEDATA, s->rcedata);
243 	intel_uncore_write(uncore, VLV_SPAREG2H, s->spare2gh);
244 
245 	/* Display CZ domain, 0x4400C-0x4402C, 0x4F000-0x4F11F */
246 	intel_uncore_write(uncore, GTIMR, s->gt_imr);
247 	intel_uncore_write(uncore, GTIER, s->gt_ier);
248 	intel_uncore_write(uncore, GEN6_PMIMR, s->pm_imr);
249 	intel_uncore_write(uncore, GEN6_PMIER, s->pm_ier);
250 
251 	for (i = 0; i < ARRAY_SIZE(s->gt_scratch); i++)
252 		intel_uncore_write(uncore, GEN7_GT_SCRATCH(i), s->gt_scratch[i]);
253 
254 	/* GT SA CZ domain, 0x100000-0x138124 */
255 	intel_uncore_write(uncore, TILECTL, s->tilectl);
256 	intel_uncore_write(uncore, GTFIFOCTL, s->gt_fifoctl);
257 	/*
258 	 * Preserve the GT allow wake and GFX force clock bit, they are not
259 	 * be restored, as they are used to control the s0ix suspend/resume
260 	 * sequence by the caller.
261 	 */
262 	val = intel_uncore_read(uncore, VLV_GTLC_WAKE_CTRL);
263 	val &= VLV_GTLC_ALLOWWAKEREQ;
264 	val |= s->gtlc_wake_ctrl & ~VLV_GTLC_ALLOWWAKEREQ;
265 	intel_uncore_write(uncore, VLV_GTLC_WAKE_CTRL, val);
266 
267 	val = intel_uncore_read(uncore, VLV_GTLC_SURVIVABILITY_REG);
268 	val &= VLV_GFX_CLK_FORCE_ON_BIT;
269 	val |= s->gtlc_survive & ~VLV_GFX_CLK_FORCE_ON_BIT;
270 	intel_uncore_write(uncore, VLV_GTLC_SURVIVABILITY_REG, val);
271 
272 	intel_uncore_write(uncore, VLV_PMWGICZ, s->pmwgicz);
273 
274 	/* Gunit-Display CZ domain, 0x182028-0x1821CF */
275 	intel_uncore_write(uncore, VLV_GU_CTL0, s->gu_ctl0);
276 	intel_uncore_write(uncore, VLV_GU_CTL1, s->gu_ctl1);
277 	intel_uncore_write(uncore, VLV_PCBR, s->pcbr);
278 	intel_uncore_write(uncore, VLV_GUNIT_CLOCK_GATE2, s->clock_gate_dis2);
279 }
280 
281 static int vlv_wait_for_pw_status(struct drm_i915_private *i915,
282 				  u32 mask, u32 val)
283 {
284 	i915_reg_t reg = VLV_GTLC_PW_STATUS;
285 	u32 reg_value;
286 	int ret;
287 
288 	/* The HW does not like us polling for PW_STATUS frequently, so
289 	 * use the sleeping loop rather than risk the busy spin within
290 	 * intel_wait_for_register().
291 	 *
292 	 * Transitioning between RC6 states should be at most 2ms (see
293 	 * valleyview_enable_rps) so use a 3ms timeout.
294 	 */
295 	ret = wait_for(((reg_value =
296 			 intel_uncore_read_notrace(&i915->uncore, reg)) & mask)
297 		       == val, 3);
298 
299 	/* just trace the final value */
300 	trace_i915_reg_rw(false, reg, reg_value, sizeof(reg_value), true);
301 
302 	return ret;
303 }
304 
305 static int vlv_force_gfx_clock(struct drm_i915_private *i915, bool force_on)
306 {
307 	struct intel_uncore *uncore = &i915->uncore;
308 	u32 val;
309 	int err;
310 
311 	val = intel_uncore_read(uncore, VLV_GTLC_SURVIVABILITY_REG);
312 	val &= ~VLV_GFX_CLK_FORCE_ON_BIT;
313 	if (force_on)
314 		val |= VLV_GFX_CLK_FORCE_ON_BIT;
315 	intel_uncore_write(uncore, VLV_GTLC_SURVIVABILITY_REG, val);
316 
317 	if (!force_on)
318 		return 0;
319 
320 	err = intel_wait_for_register(uncore,
321 				      VLV_GTLC_SURVIVABILITY_REG,
322 				      VLV_GFX_CLK_STATUS_BIT,
323 				      VLV_GFX_CLK_STATUS_BIT,
324 				      20);
325 	if (err)
326 		drm_err(&i915->drm,
327 			"timeout waiting for GFX clock force-on (%08x)\n",
328 			intel_uncore_read(uncore, VLV_GTLC_SURVIVABILITY_REG));
329 
330 	return err;
331 }
332 
333 static int vlv_allow_gt_wake(struct drm_i915_private *i915, bool allow)
334 {
335 	struct intel_uncore *uncore = &i915->uncore;
336 	u32 mask;
337 	u32 val;
338 	int err;
339 
340 	val = intel_uncore_read(uncore, VLV_GTLC_WAKE_CTRL);
341 	val &= ~VLV_GTLC_ALLOWWAKEREQ;
342 	if (allow)
343 		val |= VLV_GTLC_ALLOWWAKEREQ;
344 	intel_uncore_write(uncore, VLV_GTLC_WAKE_CTRL, val);
345 	intel_uncore_posting_read(uncore, VLV_GTLC_WAKE_CTRL);
346 
347 	mask = VLV_GTLC_ALLOWWAKEACK;
348 	val = allow ? mask : 0;
349 
350 	err = vlv_wait_for_pw_status(i915, mask, val);
351 	if (err)
352 		drm_err(&i915->drm, "timeout disabling GT waking\n");
353 
354 	return err;
355 }
356 
357 static void vlv_wait_for_gt_wells(struct drm_i915_private *dev_priv,
358 				  bool wait_for_on)
359 {
360 	u32 mask;
361 	u32 val;
362 
363 	mask = VLV_GTLC_PW_MEDIA_STATUS_MASK | VLV_GTLC_PW_RENDER_STATUS_MASK;
364 	val = wait_for_on ? mask : 0;
365 
366 	/*
367 	 * RC6 transitioning can be delayed up to 2 msec (see
368 	 * valleyview_enable_rps), use 3 msec for safety.
369 	 *
370 	 * This can fail to turn off the rc6 if the GPU is stuck after a failed
371 	 * reset and we are trying to force the machine to sleep.
372 	 */
373 	if (vlv_wait_for_pw_status(dev_priv, mask, val))
374 		drm_dbg(&dev_priv->drm,
375 			"timeout waiting for GT wells to go %s\n",
376 			onoff(wait_for_on));
377 }
378 
379 static void vlv_check_no_gt_access(struct drm_i915_private *i915)
380 {
381 	struct intel_uncore *uncore = &i915->uncore;
382 
383 	if (!(intel_uncore_read(uncore, VLV_GTLC_PW_STATUS) & VLV_GTLC_ALLOWWAKEERR))
384 		return;
385 
386 	drm_dbg(&i915->drm, "GT register access while GT waking disabled\n");
387 	intel_uncore_write(uncore, VLV_GTLC_PW_STATUS, VLV_GTLC_ALLOWWAKEERR);
388 }
389 
390 int vlv_suspend_complete(struct drm_i915_private *dev_priv)
391 {
392 	u32 mask;
393 	int err;
394 
395 	if (!IS_VALLEYVIEW(dev_priv) && !IS_CHERRYVIEW(dev_priv))
396 		return 0;
397 
398 	/*
399 	 * Bspec defines the following GT well on flags as debug only, so
400 	 * don't treat them as hard failures.
401 	 */
402 	vlv_wait_for_gt_wells(dev_priv, false);
403 
404 	mask = VLV_GTLC_RENDER_CTX_EXISTS | VLV_GTLC_MEDIA_CTX_EXISTS;
405 	drm_WARN_ON(&dev_priv->drm,
406 		    (intel_uncore_read(&dev_priv->uncore, VLV_GTLC_WAKE_CTRL) & mask) != mask);
407 
408 	vlv_check_no_gt_access(dev_priv);
409 
410 	err = vlv_force_gfx_clock(dev_priv, true);
411 	if (err)
412 		goto err1;
413 
414 	err = vlv_allow_gt_wake(dev_priv, false);
415 	if (err)
416 		goto err2;
417 
418 	vlv_save_gunit_s0ix_state(dev_priv);
419 
420 	err = vlv_force_gfx_clock(dev_priv, false);
421 	if (err)
422 		goto err2;
423 
424 	return 0;
425 
426 err2:
427 	/* For safety always re-enable waking and disable gfx clock forcing */
428 	vlv_allow_gt_wake(dev_priv, true);
429 err1:
430 	vlv_force_gfx_clock(dev_priv, false);
431 
432 	return err;
433 }
434 
435 int vlv_resume_prepare(struct drm_i915_private *dev_priv, bool rpm_resume)
436 {
437 	int err;
438 	int ret;
439 
440 	if (!IS_VALLEYVIEW(dev_priv) && !IS_CHERRYVIEW(dev_priv))
441 		return 0;
442 
443 	/*
444 	 * If any of the steps fail just try to continue, that's the best we
445 	 * can do at this point. Return the first error code (which will also
446 	 * leave RPM permanently disabled).
447 	 */
448 	ret = vlv_force_gfx_clock(dev_priv, true);
449 
450 	vlv_restore_gunit_s0ix_state(dev_priv);
451 
452 	err = vlv_allow_gt_wake(dev_priv, true);
453 	if (!ret)
454 		ret = err;
455 
456 	err = vlv_force_gfx_clock(dev_priv, false);
457 	if (!ret)
458 		ret = err;
459 
460 	vlv_check_no_gt_access(dev_priv);
461 
462 	if (rpm_resume)
463 		intel_init_clock_gating(dev_priv);
464 
465 	return ret;
466 }
467 
468 int vlv_suspend_init(struct drm_i915_private *i915)
469 {
470 	if (!IS_VALLEYVIEW(i915))
471 		return 0;
472 
473 	/* we write all the values in the struct, so no need to zero it out */
474 	i915->vlv_s0ix_state = kmalloc(sizeof(*i915->vlv_s0ix_state),
475 				       GFP_KERNEL);
476 	if (!i915->vlv_s0ix_state)
477 		return -ENOMEM;
478 
479 	return 0;
480 }
481 
482 void vlv_suspend_cleanup(struct drm_i915_private *i915)
483 {
484 	if (!i915->vlv_s0ix_state)
485 		return;
486 
487 	kfree(i915->vlv_s0ix_state);
488 	i915->vlv_s0ix_state = NULL;
489 }
490