]> bbs.cooldavid.org Git - net-next-2.6.git/blame - drivers/gpu/drm/i915/i915_suspend.c
drm/i915: Add more registers save/restore for Ironlake suspend
[net-next-2.6.git] / drivers / gpu / drm / i915 / i915_suspend.c
CommitLineData
317c35d1
JB
1/*
2 *
3 * Copyright 2008 (c) Intel Corporation
4 * Jesse Barnes <jbarnes@virtuousgeek.org>
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
21 * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25 */
26
27#include "drmP.h"
28#include "drm.h"
29#include "i915_drm.h"
30#include "i915_drv.h"
31
32static bool i915_pipe_enabled(struct drm_device *dev, enum pipe pipe)
33{
34 struct drm_i915_private *dev_priv = dev->dev_private;
42048781 35 u32 dpll_reg;
317c35d1 36
42048781
ZW
37 if (IS_IGDNG(dev)) {
38 dpll_reg = (pipe == PIPE_A) ? PCH_DPLL_A: PCH_DPLL_B;
39 } else {
40 dpll_reg = (pipe == PIPE_A) ? DPLL_A: DPLL_B;
41 }
42
43 return (I915_READ(dpll_reg) & DPLL_VCO_ENABLE);
317c35d1
JB
44}
45
46static void i915_save_palette(struct drm_device *dev, enum pipe pipe)
47{
48 struct drm_i915_private *dev_priv = dev->dev_private;
49 unsigned long reg = (pipe == PIPE_A ? PALETTE_A : PALETTE_B);
50 u32 *array;
51 int i;
52
53 if (!i915_pipe_enabled(dev, pipe))
54 return;
55
42048781
ZW
56 if (IS_IGDNG(dev))
57 reg = (pipe == PIPE_A) ? LGC_PALETTE_A : LGC_PALETTE_B;
58
317c35d1
JB
59 if (pipe == PIPE_A)
60 array = dev_priv->save_palette_a;
61 else
62 array = dev_priv->save_palette_b;
63
64 for(i = 0; i < 256; i++)
65 array[i] = I915_READ(reg + (i << 2));
66}
67
68static void i915_restore_palette(struct drm_device *dev, enum pipe pipe)
69{
70 struct drm_i915_private *dev_priv = dev->dev_private;
71 unsigned long reg = (pipe == PIPE_A ? PALETTE_A : PALETTE_B);
72 u32 *array;
73 int i;
74
75 if (!i915_pipe_enabled(dev, pipe))
76 return;
77
42048781
ZW
78 if (IS_IGDNG(dev))
79 reg = (pipe == PIPE_A) ? LGC_PALETTE_A : LGC_PALETTE_B;
80
317c35d1
JB
81 if (pipe == PIPE_A)
82 array = dev_priv->save_palette_a;
83 else
84 array = dev_priv->save_palette_b;
85
86 for(i = 0; i < 256; i++)
87 I915_WRITE(reg + (i << 2), array[i]);
88}
89
90static u8 i915_read_indexed(struct drm_device *dev, u16 index_port, u16 data_port, u8 reg)
91{
92 struct drm_i915_private *dev_priv = dev->dev_private;
93
94 I915_WRITE8(index_port, reg);
95 return I915_READ8(data_port);
96}
97
98static u8 i915_read_ar(struct drm_device *dev, u16 st01, u8 reg, u16 palette_enable)
99{
100 struct drm_i915_private *dev_priv = dev->dev_private;
101
102 I915_READ8(st01);
103 I915_WRITE8(VGA_AR_INDEX, palette_enable | reg);
104 return I915_READ8(VGA_AR_DATA_READ);
105}
106
107static void i915_write_ar(struct drm_device *dev, u16 st01, u8 reg, u8 val, u16 palette_enable)
108{
109 struct drm_i915_private *dev_priv = dev->dev_private;
110
111 I915_READ8(st01);
112 I915_WRITE8(VGA_AR_INDEX, palette_enable | reg);
113 I915_WRITE8(VGA_AR_DATA_WRITE, val);
114}
115
116static void i915_write_indexed(struct drm_device *dev, u16 index_port, u16 data_port, u8 reg, u8 val)
117{
118 struct drm_i915_private *dev_priv = dev->dev_private;
119
120 I915_WRITE8(index_port, reg);
121 I915_WRITE8(data_port, val);
122}
123
124static void i915_save_vga(struct drm_device *dev)
125{
126 struct drm_i915_private *dev_priv = dev->dev_private;
127 int i;
128 u16 cr_index, cr_data, st01;
129
130 /* VGA color palette registers */
131 dev_priv->saveDACMASK = I915_READ8(VGA_DACMASK);
317c35d1
JB
132
133 /* MSR bits */
134 dev_priv->saveMSR = I915_READ8(VGA_MSR_READ);
135 if (dev_priv->saveMSR & VGA_MSR_CGA_MODE) {
136 cr_index = VGA_CR_INDEX_CGA;
137 cr_data = VGA_CR_DATA_CGA;
138 st01 = VGA_ST01_CGA;
139 } else {
140 cr_index = VGA_CR_INDEX_MDA;
141 cr_data = VGA_CR_DATA_MDA;
142 st01 = VGA_ST01_MDA;
143 }
144
145 /* CRT controller regs */
146 i915_write_indexed(dev, cr_index, cr_data, 0x11,
147 i915_read_indexed(dev, cr_index, cr_data, 0x11) &
148 (~0x80));
149 for (i = 0; i <= 0x24; i++)
150 dev_priv->saveCR[i] =
151 i915_read_indexed(dev, cr_index, cr_data, i);
152 /* Make sure we don't turn off CR group 0 writes */
153 dev_priv->saveCR[0x11] &= ~0x80;
154
155 /* Attribute controller registers */
156 I915_READ8(st01);
157 dev_priv->saveAR_INDEX = I915_READ8(VGA_AR_INDEX);
158 for (i = 0; i <= 0x14; i++)
159 dev_priv->saveAR[i] = i915_read_ar(dev, st01, i, 0);
160 I915_READ8(st01);
161 I915_WRITE8(VGA_AR_INDEX, dev_priv->saveAR_INDEX);
162 I915_READ8(st01);
163
164 /* Graphics controller registers */
165 for (i = 0; i < 9; i++)
166 dev_priv->saveGR[i] =
167 i915_read_indexed(dev, VGA_GR_INDEX, VGA_GR_DATA, i);
168
169 dev_priv->saveGR[0x10] =
170 i915_read_indexed(dev, VGA_GR_INDEX, VGA_GR_DATA, 0x10);
171 dev_priv->saveGR[0x11] =
172 i915_read_indexed(dev, VGA_GR_INDEX, VGA_GR_DATA, 0x11);
173 dev_priv->saveGR[0x18] =
174 i915_read_indexed(dev, VGA_GR_INDEX, VGA_GR_DATA, 0x18);
175
176 /* Sequencer registers */
177 for (i = 0; i < 8; i++)
178 dev_priv->saveSR[i] =
179 i915_read_indexed(dev, VGA_SR_INDEX, VGA_SR_DATA, i);
180}
181
182static void i915_restore_vga(struct drm_device *dev)
183{
184 struct drm_i915_private *dev_priv = dev->dev_private;
185 int i;
186 u16 cr_index, cr_data, st01;
187
188 /* MSR bits */
189 I915_WRITE8(VGA_MSR_WRITE, dev_priv->saveMSR);
190 if (dev_priv->saveMSR & VGA_MSR_CGA_MODE) {
191 cr_index = VGA_CR_INDEX_CGA;
192 cr_data = VGA_CR_DATA_CGA;
193 st01 = VGA_ST01_CGA;
194 } else {
195 cr_index = VGA_CR_INDEX_MDA;
196 cr_data = VGA_CR_DATA_MDA;
197 st01 = VGA_ST01_MDA;
198 }
199
200 /* Sequencer registers, don't write SR07 */
201 for (i = 0; i < 7; i++)
202 i915_write_indexed(dev, VGA_SR_INDEX, VGA_SR_DATA, i,
203 dev_priv->saveSR[i]);
204
205 /* CRT controller regs */
206 /* Enable CR group 0 writes */
207 i915_write_indexed(dev, cr_index, cr_data, 0x11, dev_priv->saveCR[0x11]);
208 for (i = 0; i <= 0x24; i++)
209 i915_write_indexed(dev, cr_index, cr_data, i, dev_priv->saveCR[i]);
210
211 /* Graphics controller regs */
212 for (i = 0; i < 9; i++)
213 i915_write_indexed(dev, VGA_GR_INDEX, VGA_GR_DATA, i,
214 dev_priv->saveGR[i]);
215
216 i915_write_indexed(dev, VGA_GR_INDEX, VGA_GR_DATA, 0x10,
217 dev_priv->saveGR[0x10]);
218 i915_write_indexed(dev, VGA_GR_INDEX, VGA_GR_DATA, 0x11,
219 dev_priv->saveGR[0x11]);
220 i915_write_indexed(dev, VGA_GR_INDEX, VGA_GR_DATA, 0x18,
221 dev_priv->saveGR[0x18]);
222
223 /* Attribute controller registers */
224 I915_READ8(st01); /* switch back to index mode */
225 for (i = 0; i <= 0x14; i++)
226 i915_write_ar(dev, st01, i, dev_priv->saveAR[i], 0);
227 I915_READ8(st01); /* switch back to index mode */
228 I915_WRITE8(VGA_AR_INDEX, dev_priv->saveAR_INDEX | 0x20);
229 I915_READ8(st01);
230
231 /* VGA color palette registers */
232 I915_WRITE8(VGA_DACMASK, dev_priv->saveDACMASK);
317c35d1
JB
233}
234
fccdaba4 235static void i915_save_modeset_reg(struct drm_device *dev)
317c35d1
JB
236{
237 struct drm_i915_private *dev_priv = dev->dev_private;
317c35d1 238
fccdaba4
ZY
239 if (drm_core_check_feature(dev, DRIVER_MODESET))
240 return;
1341d655 241
5586c8bc
ZW
242 if (IS_IGDNG(dev)) {
243 dev_priv->savePCH_DREF_CONTROL = I915_READ(PCH_DREF_CONTROL);
244 dev_priv->saveDISP_ARB_CTL = I915_READ(DISP_ARB_CTL);
245 }
246
317c35d1
JB
247 /* Pipe & plane A info */
248 dev_priv->savePIPEACONF = I915_READ(PIPEACONF);
249 dev_priv->savePIPEASRC = I915_READ(PIPEASRC);
42048781
ZW
250 if (IS_IGDNG(dev)) {
251 dev_priv->saveFPA0 = I915_READ(PCH_FPA0);
252 dev_priv->saveFPA1 = I915_READ(PCH_FPA1);
253 dev_priv->saveDPLL_A = I915_READ(PCH_DPLL_A);
254 } else {
255 dev_priv->saveFPA0 = I915_READ(FPA0);
256 dev_priv->saveFPA1 = I915_READ(FPA1);
257 dev_priv->saveDPLL_A = I915_READ(DPLL_A);
258 }
259 if (IS_I965G(dev) && !IS_IGDNG(dev))
317c35d1
JB
260 dev_priv->saveDPLL_A_MD = I915_READ(DPLL_A_MD);
261 dev_priv->saveHTOTAL_A = I915_READ(HTOTAL_A);
262 dev_priv->saveHBLANK_A = I915_READ(HBLANK_A);
263 dev_priv->saveHSYNC_A = I915_READ(HSYNC_A);
264 dev_priv->saveVTOTAL_A = I915_READ(VTOTAL_A);
265 dev_priv->saveVBLANK_A = I915_READ(VBLANK_A);
266 dev_priv->saveVSYNC_A = I915_READ(VSYNC_A);
42048781
ZW
267 if (!IS_IGDNG(dev))
268 dev_priv->saveBCLRPAT_A = I915_READ(BCLRPAT_A);
269
270 if (IS_IGDNG(dev)) {
5586c8bc
ZW
271 dev_priv->savePIPEA_DATA_M1 = I915_READ(PIPEA_DATA_M1);
272 dev_priv->savePIPEA_DATA_N1 = I915_READ(PIPEA_DATA_N1);
273 dev_priv->savePIPEA_LINK_M1 = I915_READ(PIPEA_LINK_M1);
274 dev_priv->savePIPEA_LINK_N1 = I915_READ(PIPEA_LINK_N1);
275
42048781
ZW
276 dev_priv->saveFDI_TXA_CTL = I915_READ(FDI_TXA_CTL);
277 dev_priv->saveFDI_RXA_CTL = I915_READ(FDI_RXA_CTL);
278
279 dev_priv->savePFA_CTL_1 = I915_READ(PFA_CTL_1);
280 dev_priv->savePFA_WIN_SZ = I915_READ(PFA_WIN_SZ);
281 dev_priv->savePFA_WIN_POS = I915_READ(PFA_WIN_POS);
282
5586c8bc 283 dev_priv->saveTRANSACONF = I915_READ(TRANSACONF);
42048781
ZW
284 dev_priv->saveTRANS_HTOTAL_A = I915_READ(TRANS_HTOTAL_A);
285 dev_priv->saveTRANS_HBLANK_A = I915_READ(TRANS_HBLANK_A);
286 dev_priv->saveTRANS_HSYNC_A = I915_READ(TRANS_HSYNC_A);
287 dev_priv->saveTRANS_VTOTAL_A = I915_READ(TRANS_VTOTAL_A);
288 dev_priv->saveTRANS_VBLANK_A = I915_READ(TRANS_VBLANK_A);
289 dev_priv->saveTRANS_VSYNC_A = I915_READ(TRANS_VSYNC_A);
290 }
317c35d1
JB
291
292 dev_priv->saveDSPACNTR = I915_READ(DSPACNTR);
293 dev_priv->saveDSPASTRIDE = I915_READ(DSPASTRIDE);
294 dev_priv->saveDSPASIZE = I915_READ(DSPASIZE);
295 dev_priv->saveDSPAPOS = I915_READ(DSPAPOS);
296 dev_priv->saveDSPAADDR = I915_READ(DSPAADDR);
297 if (IS_I965G(dev)) {
298 dev_priv->saveDSPASURF = I915_READ(DSPASURF);
299 dev_priv->saveDSPATILEOFF = I915_READ(DSPATILEOFF);
300 }
301 i915_save_palette(dev, PIPE_A);
302 dev_priv->savePIPEASTAT = I915_READ(PIPEASTAT);
303
304 /* Pipe & plane B info */
305 dev_priv->savePIPEBCONF = I915_READ(PIPEBCONF);
306 dev_priv->savePIPEBSRC = I915_READ(PIPEBSRC);
42048781
ZW
307 if (IS_IGDNG(dev)) {
308 dev_priv->saveFPB0 = I915_READ(PCH_FPB0);
309 dev_priv->saveFPB1 = I915_READ(PCH_FPB1);
310 dev_priv->saveDPLL_B = I915_READ(PCH_DPLL_B);
311 } else {
312 dev_priv->saveFPB0 = I915_READ(FPB0);
313 dev_priv->saveFPB1 = I915_READ(FPB1);
314 dev_priv->saveDPLL_B = I915_READ(DPLL_B);
315 }
316 if (IS_I965G(dev) && !IS_IGDNG(dev))
317c35d1
JB
317 dev_priv->saveDPLL_B_MD = I915_READ(DPLL_B_MD);
318 dev_priv->saveHTOTAL_B = I915_READ(HTOTAL_B);
319 dev_priv->saveHBLANK_B = I915_READ(HBLANK_B);
320 dev_priv->saveHSYNC_B = I915_READ(HSYNC_B);
321 dev_priv->saveVTOTAL_B = I915_READ(VTOTAL_B);
322 dev_priv->saveVBLANK_B = I915_READ(VBLANK_B);
323 dev_priv->saveVSYNC_B = I915_READ(VSYNC_B);
42048781
ZW
324 if (!IS_IGDNG(dev))
325 dev_priv->saveBCLRPAT_B = I915_READ(BCLRPAT_B);
326
327 if (IS_IGDNG(dev)) {
5586c8bc
ZW
328 dev_priv->savePIPEB_DATA_M1 = I915_READ(PIPEB_DATA_M1);
329 dev_priv->savePIPEB_DATA_N1 = I915_READ(PIPEB_DATA_N1);
330 dev_priv->savePIPEB_LINK_M1 = I915_READ(PIPEB_LINK_M1);
331 dev_priv->savePIPEB_LINK_N1 = I915_READ(PIPEB_LINK_N1);
332
42048781
ZW
333 dev_priv->saveFDI_TXB_CTL = I915_READ(FDI_TXB_CTL);
334 dev_priv->saveFDI_RXB_CTL = I915_READ(FDI_RXB_CTL);
335
336 dev_priv->savePFB_CTL_1 = I915_READ(PFB_CTL_1);
337 dev_priv->savePFB_WIN_SZ = I915_READ(PFB_WIN_SZ);
338 dev_priv->savePFB_WIN_POS = I915_READ(PFB_WIN_POS);
339
5586c8bc 340 dev_priv->saveTRANSBCONF = I915_READ(TRANSBCONF);
42048781
ZW
341 dev_priv->saveTRANS_HTOTAL_B = I915_READ(TRANS_HTOTAL_B);
342 dev_priv->saveTRANS_HBLANK_B = I915_READ(TRANS_HBLANK_B);
343 dev_priv->saveTRANS_HSYNC_B = I915_READ(TRANS_HSYNC_B);
344 dev_priv->saveTRANS_VTOTAL_B = I915_READ(TRANS_VTOTAL_B);
345 dev_priv->saveTRANS_VBLANK_B = I915_READ(TRANS_VBLANK_B);
346 dev_priv->saveTRANS_VSYNC_B = I915_READ(TRANS_VSYNC_B);
347 }
317c35d1
JB
348
349 dev_priv->saveDSPBCNTR = I915_READ(DSPBCNTR);
350 dev_priv->saveDSPBSTRIDE = I915_READ(DSPBSTRIDE);
351 dev_priv->saveDSPBSIZE = I915_READ(DSPBSIZE);
352 dev_priv->saveDSPBPOS = I915_READ(DSPBPOS);
353 dev_priv->saveDSPBADDR = I915_READ(DSPBADDR);
b9bfdfe6 354 if (IS_I965GM(dev) || IS_GM45(dev)) {
317c35d1
JB
355 dev_priv->saveDSPBSURF = I915_READ(DSPBSURF);
356 dev_priv->saveDSPBTILEOFF = I915_READ(DSPBTILEOFF);
357 }
358 i915_save_palette(dev, PIPE_B);
359 dev_priv->savePIPEBSTAT = I915_READ(PIPEBSTAT);
fccdaba4
ZY
360 return;
361}
1341d655 362
fccdaba4
ZY
363static void i915_restore_modeset_reg(struct drm_device *dev)
364{
365 struct drm_i915_private *dev_priv = dev->dev_private;
42048781
ZW
366 int dpll_a_reg, fpa0_reg, fpa1_reg;
367 int dpll_b_reg, fpb0_reg, fpb1_reg;
fccdaba4
ZY
368
369 if (drm_core_check_feature(dev, DRIVER_MODESET))
370 return;
371
42048781
ZW
372 if (IS_IGDNG(dev)) {
373 dpll_a_reg = PCH_DPLL_A;
374 dpll_b_reg = PCH_DPLL_B;
375 fpa0_reg = PCH_FPA0;
376 fpb0_reg = PCH_FPB0;
377 fpa1_reg = PCH_FPA1;
378 fpb1_reg = PCH_FPB1;
379 } else {
380 dpll_a_reg = DPLL_A;
381 dpll_b_reg = DPLL_B;
382 fpa0_reg = FPA0;
383 fpb0_reg = FPB0;
384 fpa1_reg = FPA1;
385 fpb1_reg = FPB1;
386 }
387
5586c8bc
ZW
388 if (IS_IGDNG(dev)) {
389 I915_WRITE(PCH_DREF_CONTROL, dev_priv->savePCH_DREF_CONTROL);
390 I915_WRITE(DISP_ARB_CTL, dev_priv->saveDISP_ARB_CTL);
391 }
392
fccdaba4
ZY
393 /* Pipe & plane A info */
394 /* Prime the clock */
395 if (dev_priv->saveDPLL_A & DPLL_VCO_ENABLE) {
42048781 396 I915_WRITE(dpll_a_reg, dev_priv->saveDPLL_A &
fccdaba4
ZY
397 ~DPLL_VCO_ENABLE);
398 DRM_UDELAY(150);
399 }
42048781
ZW
400 I915_WRITE(fpa0_reg, dev_priv->saveFPA0);
401 I915_WRITE(fpa1_reg, dev_priv->saveFPA1);
fccdaba4 402 /* Actually enable it */
42048781 403 I915_WRITE(dpll_a_reg, dev_priv->saveDPLL_A);
fccdaba4 404 DRM_UDELAY(150);
42048781 405 if (IS_I965G(dev) && !IS_IGDNG(dev))
fccdaba4
ZY
406 I915_WRITE(DPLL_A_MD, dev_priv->saveDPLL_A_MD);
407 DRM_UDELAY(150);
408
409 /* Restore mode */
410 I915_WRITE(HTOTAL_A, dev_priv->saveHTOTAL_A);
411 I915_WRITE(HBLANK_A, dev_priv->saveHBLANK_A);
412 I915_WRITE(HSYNC_A, dev_priv->saveHSYNC_A);
413 I915_WRITE(VTOTAL_A, dev_priv->saveVTOTAL_A);
414 I915_WRITE(VBLANK_A, dev_priv->saveVBLANK_A);
415 I915_WRITE(VSYNC_A, dev_priv->saveVSYNC_A);
42048781
ZW
416 if (!IS_IGDNG(dev))
417 I915_WRITE(BCLRPAT_A, dev_priv->saveBCLRPAT_A);
418
419 if (IS_IGDNG(dev)) {
5586c8bc
ZW
420 I915_WRITE(PIPEA_DATA_M1, dev_priv->savePIPEA_DATA_M1);
421 I915_WRITE(PIPEA_DATA_N1, dev_priv->savePIPEA_DATA_N1);
422 I915_WRITE(PIPEA_LINK_M1, dev_priv->savePIPEA_LINK_M1);
423 I915_WRITE(PIPEA_LINK_N1, dev_priv->savePIPEA_LINK_N1);
424
42048781
ZW
425 I915_WRITE(FDI_RXA_CTL, dev_priv->saveFDI_RXA_CTL);
426 I915_WRITE(FDI_TXA_CTL, dev_priv->saveFDI_TXA_CTL);
427
428 I915_WRITE(PFA_CTL_1, dev_priv->savePFA_CTL_1);
429 I915_WRITE(PFA_WIN_SZ, dev_priv->savePFA_WIN_SZ);
430 I915_WRITE(PFA_WIN_POS, dev_priv->savePFA_WIN_POS);
431
5586c8bc 432 I915_WRITE(TRANSACONF, dev_priv->saveTRANSACONF);
42048781
ZW
433 I915_WRITE(TRANS_HTOTAL_A, dev_priv->saveTRANS_HTOTAL_A);
434 I915_WRITE(TRANS_HBLANK_A, dev_priv->saveTRANS_HBLANK_A);
435 I915_WRITE(TRANS_HSYNC_A, dev_priv->saveTRANS_HSYNC_A);
436 I915_WRITE(TRANS_VTOTAL_A, dev_priv->saveTRANS_VTOTAL_A);
437 I915_WRITE(TRANS_VBLANK_A, dev_priv->saveTRANS_VBLANK_A);
438 I915_WRITE(TRANS_VSYNC_A, dev_priv->saveTRANS_VSYNC_A);
439 }
fccdaba4
ZY
440
441 /* Restore plane info */
442 I915_WRITE(DSPASIZE, dev_priv->saveDSPASIZE);
443 I915_WRITE(DSPAPOS, dev_priv->saveDSPAPOS);
444 I915_WRITE(PIPEASRC, dev_priv->savePIPEASRC);
445 I915_WRITE(DSPAADDR, dev_priv->saveDSPAADDR);
446 I915_WRITE(DSPASTRIDE, dev_priv->saveDSPASTRIDE);
447 if (IS_I965G(dev)) {
448 I915_WRITE(DSPASURF, dev_priv->saveDSPASURF);
449 I915_WRITE(DSPATILEOFF, dev_priv->saveDSPATILEOFF);
450 }
451
452 I915_WRITE(PIPEACONF, dev_priv->savePIPEACONF);
453
454 i915_restore_palette(dev, PIPE_A);
455 /* Enable the plane */
456 I915_WRITE(DSPACNTR, dev_priv->saveDSPACNTR);
457 I915_WRITE(DSPAADDR, I915_READ(DSPAADDR));
458
459 /* Pipe & plane B info */
460 if (dev_priv->saveDPLL_B & DPLL_VCO_ENABLE) {
42048781 461 I915_WRITE(dpll_b_reg, dev_priv->saveDPLL_B &
fccdaba4
ZY
462 ~DPLL_VCO_ENABLE);
463 DRM_UDELAY(150);
464 }
42048781
ZW
465 I915_WRITE(fpb0_reg, dev_priv->saveFPB0);
466 I915_WRITE(fpb1_reg, dev_priv->saveFPB1);
fccdaba4 467 /* Actually enable it */
42048781 468 I915_WRITE(dpll_b_reg, dev_priv->saveDPLL_B);
fccdaba4 469 DRM_UDELAY(150);
5586c8bc 470 if (IS_I965G(dev) && !IS_IGDNG(dev))
fccdaba4
ZY
471 I915_WRITE(DPLL_B_MD, dev_priv->saveDPLL_B_MD);
472 DRM_UDELAY(150);
473
474 /* Restore mode */
475 I915_WRITE(HTOTAL_B, dev_priv->saveHTOTAL_B);
476 I915_WRITE(HBLANK_B, dev_priv->saveHBLANK_B);
477 I915_WRITE(HSYNC_B, dev_priv->saveHSYNC_B);
478 I915_WRITE(VTOTAL_B, dev_priv->saveVTOTAL_B);
479 I915_WRITE(VBLANK_B, dev_priv->saveVBLANK_B);
480 I915_WRITE(VSYNC_B, dev_priv->saveVSYNC_B);
42048781
ZW
481 if (!IS_IGDNG(dev))
482 I915_WRITE(BCLRPAT_B, dev_priv->saveBCLRPAT_B);
483
484 if (IS_IGDNG(dev)) {
5586c8bc
ZW
485 I915_WRITE(PIPEB_DATA_M1, dev_priv->savePIPEB_DATA_M1);
486 I915_WRITE(PIPEB_DATA_N1, dev_priv->savePIPEB_DATA_N1);
487 I915_WRITE(PIPEB_LINK_M1, dev_priv->savePIPEB_LINK_M1);
488 I915_WRITE(PIPEB_LINK_N1, dev_priv->savePIPEB_LINK_N1);
489
42048781
ZW
490 I915_WRITE(FDI_RXB_CTL, dev_priv->saveFDI_RXB_CTL);
491 I915_WRITE(FDI_TXB_CTL, dev_priv->saveFDI_TXB_CTL);
492
493 I915_WRITE(PFB_CTL_1, dev_priv->savePFB_CTL_1);
494 I915_WRITE(PFB_WIN_SZ, dev_priv->savePFB_WIN_SZ);
495 I915_WRITE(PFB_WIN_POS, dev_priv->savePFB_WIN_POS);
496
5586c8bc 497 I915_WRITE(TRANSBCONF, dev_priv->saveTRANSBCONF);
42048781
ZW
498 I915_WRITE(TRANS_HTOTAL_B, dev_priv->saveTRANS_HTOTAL_B);
499 I915_WRITE(TRANS_HBLANK_B, dev_priv->saveTRANS_HBLANK_B);
500 I915_WRITE(TRANS_HSYNC_B, dev_priv->saveTRANS_HSYNC_B);
501 I915_WRITE(TRANS_VTOTAL_B, dev_priv->saveTRANS_VTOTAL_B);
502 I915_WRITE(TRANS_VBLANK_B, dev_priv->saveTRANS_VBLANK_B);
503 I915_WRITE(TRANS_VSYNC_B, dev_priv->saveTRANS_VSYNC_B);
504 }
fccdaba4
ZY
505
506 /* Restore plane info */
507 I915_WRITE(DSPBSIZE, dev_priv->saveDSPBSIZE);
508 I915_WRITE(DSPBPOS, dev_priv->saveDSPBPOS);
509 I915_WRITE(PIPEBSRC, dev_priv->savePIPEBSRC);
510 I915_WRITE(DSPBADDR, dev_priv->saveDSPBADDR);
511 I915_WRITE(DSPBSTRIDE, dev_priv->saveDSPBSTRIDE);
512 if (IS_I965G(dev)) {
513 I915_WRITE(DSPBSURF, dev_priv->saveDSPBSURF);
514 I915_WRITE(DSPBTILEOFF, dev_priv->saveDSPBTILEOFF);
515 }
516
517 I915_WRITE(PIPEBCONF, dev_priv->savePIPEBCONF);
518
519 i915_restore_palette(dev, PIPE_B);
520 /* Enable the plane */
521 I915_WRITE(DSPBCNTR, dev_priv->saveDSPBCNTR);
522 I915_WRITE(DSPBADDR, I915_READ(DSPBADDR));
317c35d1 523
fccdaba4
ZY
524 return;
525}
1341d655
BG
526
527void i915_save_display(struct drm_device *dev)
fccdaba4
ZY
528{
529 struct drm_i915_private *dev_priv = dev->dev_private;
fccdaba4
ZY
530
531 /* Display arbitration control */
532 dev_priv->saveDSPARB = I915_READ(DSPARB);
533
534 /* This is only meaningful in non-KMS mode */
535 /* Don't save them in KMS mode */
536 i915_save_modeset_reg(dev);
1341d655 537
1fd1c624
EA
538 /* Cursor state */
539 dev_priv->saveCURACNTR = I915_READ(CURACNTR);
540 dev_priv->saveCURAPOS = I915_READ(CURAPOS);
541 dev_priv->saveCURABASE = I915_READ(CURABASE);
542 dev_priv->saveCURBCNTR = I915_READ(CURBCNTR);
543 dev_priv->saveCURBPOS = I915_READ(CURBPOS);
544 dev_priv->saveCURBBASE = I915_READ(CURBBASE);
545 if (!IS_I9XX(dev))
546 dev_priv->saveCURSIZE = I915_READ(CURSIZE);
547
317c35d1 548 /* CRT state */
42048781
ZW
549 if (IS_IGDNG(dev)) {
550 dev_priv->saveADPA = I915_READ(PCH_ADPA);
551 } else {
552 dev_priv->saveADPA = I915_READ(ADPA);
553 }
317c35d1
JB
554
555 /* LVDS state */
42048781
ZW
556 if (IS_IGDNG(dev)) {
557 dev_priv->savePP_CONTROL = I915_READ(PCH_PP_CONTROL);
558 dev_priv->saveBLC_PWM_CTL = I915_READ(BLC_PWM_PCH_CTL1);
559 dev_priv->saveBLC_PWM_CTL2 = I915_READ(BLC_PWM_PCH_CTL2);
560 dev_priv->saveBLC_CPU_PWM_CTL = I915_READ(BLC_PWM_CPU_CTL);
561 dev_priv->saveBLC_CPU_PWM_CTL2 = I915_READ(BLC_PWM_CPU_CTL2);
562 dev_priv->saveLVDS = I915_READ(PCH_LVDS);
563 } else {
564 dev_priv->savePP_CONTROL = I915_READ(PP_CONTROL);
565 dev_priv->savePFIT_PGM_RATIOS = I915_READ(PFIT_PGM_RATIOS);
566 dev_priv->saveBLC_PWM_CTL = I915_READ(BLC_PWM_CTL);
567 dev_priv->saveBLC_HIST_CTL = I915_READ(BLC_HIST_CTL);
568 if (IS_I965G(dev))
569 dev_priv->saveBLC_PWM_CTL2 = I915_READ(BLC_PWM_CTL2);
570 if (IS_MOBILE(dev) && !IS_I830(dev))
571 dev_priv->saveLVDS = I915_READ(LVDS);
572 }
573
574 if (!IS_I830(dev) && !IS_845G(dev) && !IS_IGDNG(dev))
317c35d1 575 dev_priv->savePFIT_CONTROL = I915_READ(PFIT_CONTROL);
42048781
ZW
576
577 if (IS_IGDNG(dev)) {
578 dev_priv->savePP_ON_DELAYS = I915_READ(PCH_PP_ON_DELAYS);
579 dev_priv->savePP_OFF_DELAYS = I915_READ(PCH_PP_OFF_DELAYS);
580 dev_priv->savePP_DIVISOR = I915_READ(PCH_PP_DIVISOR);
581 } else {
582 dev_priv->savePP_ON_DELAYS = I915_READ(PP_ON_DELAYS);
583 dev_priv->savePP_OFF_DELAYS = I915_READ(PP_OFF_DELAYS);
584 dev_priv->savePP_DIVISOR = I915_READ(PP_DIVISOR);
585 }
317c35d1 586
a4fc5ed6
KP
587 /* Display Port state */
588 if (SUPPORTS_INTEGRATED_DP(dev)) {
589 dev_priv->saveDP_B = I915_READ(DP_B);
590 dev_priv->saveDP_C = I915_READ(DP_C);
591 dev_priv->saveDP_D = I915_READ(DP_D);
592 dev_priv->savePIPEA_GMCH_DATA_M = I915_READ(PIPEA_GMCH_DATA_M);
593 dev_priv->savePIPEB_GMCH_DATA_M = I915_READ(PIPEB_GMCH_DATA_M);
594 dev_priv->savePIPEA_GMCH_DATA_N = I915_READ(PIPEA_GMCH_DATA_N);
595 dev_priv->savePIPEB_GMCH_DATA_N = I915_READ(PIPEB_GMCH_DATA_N);
596 dev_priv->savePIPEA_DP_LINK_M = I915_READ(PIPEA_DP_LINK_M);
597 dev_priv->savePIPEB_DP_LINK_M = I915_READ(PIPEB_DP_LINK_M);
598 dev_priv->savePIPEA_DP_LINK_N = I915_READ(PIPEA_DP_LINK_N);
599 dev_priv->savePIPEB_DP_LINK_N = I915_READ(PIPEB_DP_LINK_N);
600 }
317c35d1
JB
601 /* FIXME: save TV & SDVO state */
602
603 /* FBC state */
06027f91
JB
604 if (IS_GM45(dev)) {
605 dev_priv->saveDPFC_CB_BASE = I915_READ(DPFC_CB_BASE);
606 } else {
607 dev_priv->saveFBC_CFB_BASE = I915_READ(FBC_CFB_BASE);
608 dev_priv->saveFBC_LL_BASE = I915_READ(FBC_LL_BASE);
609 dev_priv->saveFBC_CONTROL2 = I915_READ(FBC_CONTROL2);
610 dev_priv->saveFBC_CONTROL = I915_READ(FBC_CONTROL);
611 }
317c35d1 612
317c35d1
JB
613 /* VGA state */
614 dev_priv->saveVGA0 = I915_READ(VGA0);
615 dev_priv->saveVGA1 = I915_READ(VGA1);
616 dev_priv->saveVGA_PD = I915_READ(VGA_PD);
42048781
ZW
617 if (IS_IGDNG(dev))
618 dev_priv->saveVGACNTRL = I915_READ(CPU_VGACNTRL);
619 else
620 dev_priv->saveVGACNTRL = I915_READ(VGACNTRL);
317c35d1 621
317c35d1 622 i915_save_vga(dev);
317c35d1
JB
623}
624
1341d655 625void i915_restore_display(struct drm_device *dev)
317c35d1
JB
626{
627 struct drm_i915_private *dev_priv = dev->dev_private;
461cba2d 628
881ee988 629 /* Display arbitration */
317c35d1
JB
630 I915_WRITE(DSPARB, dev_priv->saveDSPARB);
631
a4fc5ed6
KP
632 /* Display port ratios (must be done before clock is set) */
633 if (SUPPORTS_INTEGRATED_DP(dev)) {
634 I915_WRITE(PIPEA_GMCH_DATA_M, dev_priv->savePIPEA_GMCH_DATA_M);
635 I915_WRITE(PIPEB_GMCH_DATA_M, dev_priv->savePIPEB_GMCH_DATA_M);
636 I915_WRITE(PIPEA_GMCH_DATA_N, dev_priv->savePIPEA_GMCH_DATA_N);
637 I915_WRITE(PIPEB_GMCH_DATA_N, dev_priv->savePIPEB_GMCH_DATA_N);
638 I915_WRITE(PIPEA_DP_LINK_M, dev_priv->savePIPEA_DP_LINK_M);
639 I915_WRITE(PIPEB_DP_LINK_M, dev_priv->savePIPEB_DP_LINK_M);
640 I915_WRITE(PIPEA_DP_LINK_N, dev_priv->savePIPEA_DP_LINK_N);
641 I915_WRITE(PIPEB_DP_LINK_N, dev_priv->savePIPEB_DP_LINK_N);
642 }
1341d655 643
fccdaba4
ZY
644 /* This is only meaningful in non-KMS mode */
645 /* Don't restore them in KMS mode */
646 i915_restore_modeset_reg(dev);
1341d655 647
1fd1c624
EA
648 /* Cursor state */
649 I915_WRITE(CURAPOS, dev_priv->saveCURAPOS);
650 I915_WRITE(CURACNTR, dev_priv->saveCURACNTR);
651 I915_WRITE(CURABASE, dev_priv->saveCURABASE);
652 I915_WRITE(CURBPOS, dev_priv->saveCURBPOS);
653 I915_WRITE(CURBCNTR, dev_priv->saveCURBCNTR);
654 I915_WRITE(CURBBASE, dev_priv->saveCURBBASE);
655 if (!IS_I9XX(dev))
656 I915_WRITE(CURSIZE, dev_priv->saveCURSIZE);
657
317c35d1 658 /* CRT state */
42048781
ZW
659 if (IS_IGDNG(dev))
660 I915_WRITE(PCH_ADPA, dev_priv->saveADPA);
661 else
662 I915_WRITE(ADPA, dev_priv->saveADPA);
317c35d1
JB
663
664 /* LVDS state */
42048781 665 if (IS_I965G(dev) && !IS_IGDNG(dev))
317c35d1 666 I915_WRITE(BLC_PWM_CTL2, dev_priv->saveBLC_PWM_CTL2);
42048781
ZW
667
668 if (IS_IGDNG(dev)) {
669 I915_WRITE(PCH_LVDS, dev_priv->saveLVDS);
670 } else if (IS_MOBILE(dev) && !IS_I830(dev))
317c35d1 671 I915_WRITE(LVDS, dev_priv->saveLVDS);
42048781
ZW
672
673 if (!IS_I830(dev) && !IS_845G(dev) && !IS_IGDNG(dev))
317c35d1
JB
674 I915_WRITE(PFIT_CONTROL, dev_priv->savePFIT_CONTROL);
675
42048781
ZW
676 if (IS_IGDNG(dev)) {
677 I915_WRITE(BLC_PWM_PCH_CTL1, dev_priv->saveBLC_PWM_CTL);
678 I915_WRITE(BLC_PWM_PCH_CTL2, dev_priv->saveBLC_PWM_CTL2);
679 I915_WRITE(BLC_PWM_CPU_CTL, dev_priv->saveBLC_CPU_PWM_CTL);
680 I915_WRITE(BLC_PWM_CPU_CTL2, dev_priv->saveBLC_CPU_PWM_CTL2);
681 I915_WRITE(PCH_PP_ON_DELAYS, dev_priv->savePP_ON_DELAYS);
682 I915_WRITE(PCH_PP_OFF_DELAYS, dev_priv->savePP_OFF_DELAYS);
683 I915_WRITE(PCH_PP_DIVISOR, dev_priv->savePP_DIVISOR);
684 I915_WRITE(PCH_PP_CONTROL, dev_priv->savePP_CONTROL);
685 } else {
686 I915_WRITE(PFIT_PGM_RATIOS, dev_priv->savePFIT_PGM_RATIOS);
687 I915_WRITE(BLC_PWM_CTL, dev_priv->saveBLC_PWM_CTL);
688 I915_WRITE(BLC_HIST_CTL, dev_priv->saveBLC_HIST_CTL);
689 I915_WRITE(PP_ON_DELAYS, dev_priv->savePP_ON_DELAYS);
690 I915_WRITE(PP_OFF_DELAYS, dev_priv->savePP_OFF_DELAYS);
691 I915_WRITE(PP_DIVISOR, dev_priv->savePP_DIVISOR);
692 I915_WRITE(PP_CONTROL, dev_priv->savePP_CONTROL);
693 }
317c35d1 694
a4fc5ed6
KP
695 /* Display Port state */
696 if (SUPPORTS_INTEGRATED_DP(dev)) {
697 I915_WRITE(DP_B, dev_priv->saveDP_B);
698 I915_WRITE(DP_C, dev_priv->saveDP_C);
699 I915_WRITE(DP_D, dev_priv->saveDP_D);
700 }
317c35d1
JB
701 /* FIXME: restore TV & SDVO state */
702
703 /* FBC info */
06027f91
JB
704 if (IS_GM45(dev)) {
705 g4x_disable_fbc(dev);
706 I915_WRITE(DPFC_CB_BASE, dev_priv->saveDPFC_CB_BASE);
707 } else {
708 i8xx_disable_fbc(dev);
709 I915_WRITE(FBC_CFB_BASE, dev_priv->saveFBC_CFB_BASE);
710 I915_WRITE(FBC_LL_BASE, dev_priv->saveFBC_LL_BASE);
711 I915_WRITE(FBC_CONTROL2, dev_priv->saveFBC_CONTROL2);
712 I915_WRITE(FBC_CONTROL, dev_priv->saveFBC_CONTROL);
713 }
317c35d1
JB
714
715 /* VGA state */
42048781
ZW
716 if (IS_IGDNG(dev))
717 I915_WRITE(CPU_VGACNTRL, dev_priv->saveVGACNTRL);
718 else
719 I915_WRITE(VGACNTRL, dev_priv->saveVGACNTRL);
317c35d1
JB
720 I915_WRITE(VGA0, dev_priv->saveVGA0);
721 I915_WRITE(VGA1, dev_priv->saveVGA1);
722 I915_WRITE(VGA_PD, dev_priv->saveVGA_PD);
723 DRM_UDELAY(150);
724
1341d655
BG
725 i915_restore_vga(dev);
726}
727
728int i915_save_state(struct drm_device *dev)
729{
730 struct drm_i915_private *dev_priv = dev->dev_private;
731 int i;
732
733 pci_read_config_byte(dev->pdev, LBB, &dev_priv->saveLBB);
734
735 /* Render Standby */
736 if (IS_I965G(dev) && IS_MOBILE(dev))
737 dev_priv->saveRENDERSTANDBY = I915_READ(MCHBAR_RENDER_STANDBY);
738
739 /* Hardware status page */
740 dev_priv->saveHWS = I915_READ(HWS_PGA);
741
742 i915_save_display(dev);
743
744 /* Interrupt state */
42048781
ZW
745 if (IS_IGDNG(dev)) {
746 dev_priv->saveDEIER = I915_READ(DEIER);
747 dev_priv->saveDEIMR = I915_READ(DEIMR);
748 dev_priv->saveGTIER = I915_READ(GTIER);
749 dev_priv->saveGTIMR = I915_READ(GTIMR);
750 dev_priv->saveFDI_RXA_IMR = I915_READ(FDI_RXA_IMR);
751 dev_priv->saveFDI_RXB_IMR = I915_READ(FDI_RXB_IMR);
752 } else {
753 dev_priv->saveIER = I915_READ(IER);
754 dev_priv->saveIMR = I915_READ(IMR);
755 }
1341d655
BG
756
757 /* Clock gating state */
758 dev_priv->saveD_STATE = I915_READ(D_STATE);
759 dev_priv->saveDSPCLK_GATE_D = I915_READ(DSPCLK_GATE_D); /* Not sure about this */
760
761 /* Cache mode state */
762 dev_priv->saveCACHE_MODE_0 = I915_READ(CACHE_MODE_0);
763
764 /* Memory Arbitration state */
765 dev_priv->saveMI_ARB_STATE = I915_READ(MI_ARB_STATE);
766
767 /* Scratch space */
768 for (i = 0; i < 16; i++) {
769 dev_priv->saveSWF0[i] = I915_READ(SWF00 + (i << 2));
770 dev_priv->saveSWF1[i] = I915_READ(SWF10 + (i << 2));
771 }
772 for (i = 0; i < 3; i++)
773 dev_priv->saveSWF2[i] = I915_READ(SWF30 + (i << 2));
774
775 /* Fences */
776 if (IS_I965G(dev)) {
777 for (i = 0; i < 16; i++)
778 dev_priv->saveFENCE[i] = I915_READ64(FENCE_REG_965_0 + (i * 8));
779 } else {
780 for (i = 0; i < 8; i++)
781 dev_priv->saveFENCE[i] = I915_READ(FENCE_REG_830_0 + (i * 4));
782
783 if (IS_I945G(dev) || IS_I945GM(dev) || IS_G33(dev))
784 for (i = 0; i < 8; i++)
785 dev_priv->saveFENCE[i+8] = I915_READ(FENCE_REG_945_8 + (i * 4));
786 }
787
788 return 0;
789}
790
791int i915_restore_state(struct drm_device *dev)
792{
793 struct drm_i915_private *dev_priv = dev->dev_private;
794 int i;
795
796 pci_write_config_byte(dev->pdev, LBB, dev_priv->saveLBB);
797
798 /* Render Standby */
799 if (IS_I965G(dev) && IS_MOBILE(dev))
800 I915_WRITE(MCHBAR_RENDER_STANDBY, dev_priv->saveRENDERSTANDBY);
801
802 /* Hardware status page */
803 I915_WRITE(HWS_PGA, dev_priv->saveHWS);
804
805 /* Fences */
806 if (IS_I965G(dev)) {
807 for (i = 0; i < 16; i++)
808 I915_WRITE64(FENCE_REG_965_0 + (i * 8), dev_priv->saveFENCE[i]);
809 } else {
810 for (i = 0; i < 8; i++)
811 I915_WRITE(FENCE_REG_830_0 + (i * 4), dev_priv->saveFENCE[i]);
812 if (IS_I945G(dev) || IS_I945GM(dev) || IS_G33(dev))
813 for (i = 0; i < 8; i++)
814 I915_WRITE(FENCE_REG_945_8 + (i * 4), dev_priv->saveFENCE[i+8]);
815 }
816
817 i915_restore_display(dev);
818
819 /* Interrupt state */
42048781
ZW
820 if (IS_IGDNG(dev)) {
821 I915_WRITE(DEIER, dev_priv->saveDEIER);
822 I915_WRITE(DEIMR, dev_priv->saveDEIMR);
823 I915_WRITE(GTIER, dev_priv->saveGTIER);
824 I915_WRITE(GTIMR, dev_priv->saveGTIMR);
825 I915_WRITE(FDI_RXA_IMR, dev_priv->saveFDI_RXA_IMR);
826 I915_WRITE(FDI_RXB_IMR, dev_priv->saveFDI_RXB_IMR);
827 } else {
828 I915_WRITE (IER, dev_priv->saveIER);
829 I915_WRITE (IMR, dev_priv->saveIMR);
830 }
1341d655 831
317c35d1
JB
832 /* Clock gating state */
833 I915_WRITE (D_STATE, dev_priv->saveD_STATE);
652c393a 834 I915_WRITE (DSPCLK_GATE_D, dev_priv->saveDSPCLK_GATE_D);
317c35d1
JB
835
836 /* Cache mode state */
837 I915_WRITE (CACHE_MODE_0, dev_priv->saveCACHE_MODE_0 | 0xffff0000);
838
839 /* Memory arbitration state */
840 I915_WRITE (MI_ARB_STATE, dev_priv->saveMI_ARB_STATE | 0xffff0000);
841
842 for (i = 0; i < 16; i++) {
843 I915_WRITE(SWF00 + (i << 2), dev_priv->saveSWF0[i]);
819e0064 844 I915_WRITE(SWF10 + (i << 2), dev_priv->saveSWF1[i]);
317c35d1
JB
845 }
846 for (i = 0; i < 3; i++)
847 I915_WRITE(SWF30 + (i << 2), dev_priv->saveSWF2[i]);
848
317c35d1
JB
849 return 0;
850}
851