1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright 2010 Matt Turner.
4  * Copyright 2012 Red Hat
5  *
6  * Authors: Matthew Garrett
7  *	    Matt Turner
8  *	    Dave Airlie
9  */
10 
11 #include <linux/delay.h>
12 #include <linux/iosys-map.h>
13 
14 #include <drm/drm_atomic_helper.h>
15 #include <drm/drm_atomic_state_helper.h>
16 #include <drm/drm_crtc_helper.h>
17 #include <drm/drm_damage_helper.h>
18 #include <drm/drm_format_helper.h>
19 #include <drm/drm_fourcc.h>
20 #include <drm/drm_gem_atomic_helper.h>
21 #include <drm/drm_gem_framebuffer_helper.h>
22 #include <drm/drm_plane_helper.h>
23 #include <drm/drm_print.h>
24 #include <drm/drm_probe_helper.h>
25 #include <drm/drm_simple_kms_helper.h>
26 
27 #include "mgag200_drv.h"
28 
29 #define MGAG200_LUT_SIZE 256
30 
31 /*
32  * This file contains setup code for the CRTC.
33  */
34 
35 static void mgag200_crtc_set_gamma_linear(struct mga_device *mdev,
36 					  const struct drm_format_info *format)
37 {
38 	int i;
39 
40 	WREG8(DAC_INDEX + MGA1064_INDEX, 0);
41 
42 	switch (format->format) {
43 	case DRM_FORMAT_RGB565:
44 		/* Use better interpolation, to take 32 values from 0 to 255 */
45 		for (i = 0; i < MGAG200_LUT_SIZE / 8; i++) {
46 			WREG8(DAC_INDEX + MGA1064_COL_PAL, i * 8 + i / 4);
47 			WREG8(DAC_INDEX + MGA1064_COL_PAL, i * 4 + i / 16);
48 			WREG8(DAC_INDEX + MGA1064_COL_PAL, i * 8 + i / 4);
49 		}
50 		/* Green has one more bit, so add padding with 0 for red and blue. */
51 		for (i = MGAG200_LUT_SIZE / 8; i < MGAG200_LUT_SIZE / 4; i++) {
52 			WREG8(DAC_INDEX + MGA1064_COL_PAL, 0);
53 			WREG8(DAC_INDEX + MGA1064_COL_PAL, i * 4 + i / 16);
54 			WREG8(DAC_INDEX + MGA1064_COL_PAL, 0);
55 		}
56 		break;
57 	case DRM_FORMAT_RGB888:
58 	case DRM_FORMAT_XRGB8888:
59 		for (i = 0; i < MGAG200_LUT_SIZE; i++) {
60 			WREG8(DAC_INDEX + MGA1064_COL_PAL, i);
61 			WREG8(DAC_INDEX + MGA1064_COL_PAL, i);
62 			WREG8(DAC_INDEX + MGA1064_COL_PAL, i);
63 		}
64 		break;
65 	default:
66 		drm_warn_once(&mdev->base, "Unsupported format %p4cc for gamma correction\n",
67 			      &format->format);
68 		break;
69 	}
70 }
71 
72 static void mgag200_crtc_set_gamma(struct mga_device *mdev,
73 				   const struct drm_format_info *format,
74 				   struct drm_color_lut *lut)
75 {
76 	int i;
77 
78 	WREG8(DAC_INDEX + MGA1064_INDEX, 0);
79 
80 	switch (format->format) {
81 	case DRM_FORMAT_RGB565:
82 		/* Use better interpolation, to take 32 values from lut[0] to lut[255] */
83 		for (i = 0; i < MGAG200_LUT_SIZE / 8; i++) {
84 			WREG8(DAC_INDEX + MGA1064_COL_PAL, lut[i * 8 + i / 4].red >> 8);
85 			WREG8(DAC_INDEX + MGA1064_COL_PAL, lut[i * 4 + i / 16].green >> 8);
86 			WREG8(DAC_INDEX + MGA1064_COL_PAL, lut[i * 8 + i / 4].blue >> 8);
87 		}
88 		/* Green has one more bit, so add padding with 0 for red and blue. */
89 		for (i = MGAG200_LUT_SIZE / 8; i < MGAG200_LUT_SIZE / 4; i++) {
90 			WREG8(DAC_INDEX + MGA1064_COL_PAL, 0);
91 			WREG8(DAC_INDEX + MGA1064_COL_PAL, lut[i * 4 + i / 16].green >> 8);
92 			WREG8(DAC_INDEX + MGA1064_COL_PAL, 0);
93 		}
94 		break;
95 	case DRM_FORMAT_RGB888:
96 	case DRM_FORMAT_XRGB8888:
97 		for (i = 0; i < MGAG200_LUT_SIZE; i++) {
98 			WREG8(DAC_INDEX + MGA1064_COL_PAL, lut[i].red >> 8);
99 			WREG8(DAC_INDEX + MGA1064_COL_PAL, lut[i].green >> 8);
100 			WREG8(DAC_INDEX + MGA1064_COL_PAL, lut[i].blue >> 8);
101 		}
102 		break;
103 	default:
104 		drm_warn_once(&mdev->base, "Unsupported format %p4cc for gamma correction\n",
105 			      &format->format);
106 		break;
107 	}
108 }
109 
110 static inline void mga_wait_vsync(struct mga_device *mdev)
111 {
112 	unsigned long timeout = jiffies + HZ/10;
113 	unsigned int status = 0;
114 
115 	do {
116 		status = RREG32(MGAREG_Status);
117 	} while ((status & 0x08) && time_before(jiffies, timeout));
118 	timeout = jiffies + HZ/10;
119 	status = 0;
120 	do {
121 		status = RREG32(MGAREG_Status);
122 	} while (!(status & 0x08) && time_before(jiffies, timeout));
123 }
124 
125 static inline void mga_wait_busy(struct mga_device *mdev)
126 {
127 	unsigned long timeout = jiffies + HZ;
128 	unsigned int status = 0;
129 	do {
130 		status = RREG8(MGAREG_Status + 2);
131 	} while ((status & 0x01) && time_before(jiffies, timeout));
132 }
133 
134 static void mgag200_g200wb_hold_bmc(struct mga_device *mdev)
135 {
136 	u8 tmp;
137 	int iter_max;
138 
139 	/* 1- The first step is to warn the BMC of an upcoming mode change.
140 	 * We are putting the misc<0> to output.*/
141 
142 	WREG8(DAC_INDEX, MGA1064_GEN_IO_CTL);
143 	tmp = RREG8(DAC_DATA);
144 	tmp |= 0x10;
145 	WREG_DAC(MGA1064_GEN_IO_CTL, tmp);
146 
147 	/* we are putting a 1 on the misc<0> line */
148 	WREG8(DAC_INDEX, MGA1064_GEN_IO_DATA);
149 	tmp = RREG8(DAC_DATA);
150 	tmp |= 0x10;
151 	WREG_DAC(MGA1064_GEN_IO_DATA, tmp);
152 
153 	/* 2- Second step to mask and further scan request
154 	 * This will be done by asserting the remfreqmsk bit (XSPAREREG<7>)
155 	 */
156 	WREG8(DAC_INDEX, MGA1064_SPAREREG);
157 	tmp = RREG8(DAC_DATA);
158 	tmp |= 0x80;
159 	WREG_DAC(MGA1064_SPAREREG, tmp);
160 
161 	/* 3a- the third step is to verifu if there is an active scan
162 	 * We are searching for a 0 on remhsyncsts <XSPAREREG<0>)
163 	 */
164 	iter_max = 300;
165 	while (!(tmp & 0x1) && iter_max) {
166 		WREG8(DAC_INDEX, MGA1064_SPAREREG);
167 		tmp = RREG8(DAC_DATA);
168 		udelay(1000);
169 		iter_max--;
170 	}
171 
172 	/* 3b- this step occurs only if the remove is actually scanning
173 	 * we are waiting for the end of the frame which is a 1 on
174 	 * remvsyncsts (XSPAREREG<1>)
175 	 */
176 	if (iter_max) {
177 		iter_max = 300;
178 		while ((tmp & 0x2) && iter_max) {
179 			WREG8(DAC_INDEX, MGA1064_SPAREREG);
180 			tmp = RREG8(DAC_DATA);
181 			udelay(1000);
182 			iter_max--;
183 		}
184 	}
185 }
186 
187 static void mgag200_g200wb_release_bmc(struct mga_device *mdev)
188 {
189 	u8 tmp;
190 
191 	/* 1- The first step is to ensure that the vrsten and hrsten are set */
192 	WREG8(MGAREG_CRTCEXT_INDEX, 1);
193 	tmp = RREG8(MGAREG_CRTCEXT_DATA);
194 	WREG8(MGAREG_CRTCEXT_DATA, tmp | 0x88);
195 
196 	/* 2- second step is to assert the rstlvl2 */
197 	WREG8(DAC_INDEX, MGA1064_REMHEADCTL2);
198 	tmp = RREG8(DAC_DATA);
199 	tmp |= 0x8;
200 	WREG8(DAC_DATA, tmp);
201 
202 	/* wait 10 us */
203 	udelay(10);
204 
205 	/* 3- deassert rstlvl2 */
206 	tmp &= ~0x08;
207 	WREG8(DAC_INDEX, MGA1064_REMHEADCTL2);
208 	WREG8(DAC_DATA, tmp);
209 
210 	/* 4- remove mask of scan request */
211 	WREG8(DAC_INDEX, MGA1064_SPAREREG);
212 	tmp = RREG8(DAC_DATA);
213 	tmp &= ~0x80;
214 	WREG8(DAC_DATA, tmp);
215 
216 	/* 5- put back a 0 on the misc<0> line */
217 	WREG8(DAC_INDEX, MGA1064_GEN_IO_DATA);
218 	tmp = RREG8(DAC_DATA);
219 	tmp &= ~0x10;
220 	WREG_DAC(MGA1064_GEN_IO_DATA, tmp);
221 }
222 
223 /*
224  * This is how the framebuffer base address is stored in g200 cards:
225  *   * Assume @offset is the gpu_addr variable of the framebuffer object
226  *   * Then addr is the number of _pixels_ (not bytes) from the start of
227  *     VRAM to the first pixel we want to display. (divided by 2 for 32bit
228  *     framebuffers)
229  *   * addr is stored in the CRTCEXT0, CRTCC and CRTCD registers
230  *      addr<20> -> CRTCEXT0<6>
231  *      addr<19-16> -> CRTCEXT0<3-0>
232  *      addr<15-8> -> CRTCC<7-0>
233  *      addr<7-0> -> CRTCD<7-0>
234  *
235  *  CRTCEXT0 has to be programmed last to trigger an update and make the
236  *  new addr variable take effect.
237  */
238 static void mgag200_set_startadd(struct mga_device *mdev,
239 				 unsigned long offset)
240 {
241 	struct drm_device *dev = &mdev->base;
242 	u32 startadd;
243 	u8 crtcc, crtcd, crtcext0;
244 
245 	startadd = offset / 8;
246 
247 	if (startadd > 0)
248 		drm_WARN_ON_ONCE(dev, mdev->info->bug_no_startadd);
249 
250 	/*
251 	 * Can't store addresses any higher than that, but we also
252 	 * don't have more than 16 MiB of memory, so it should be fine.
253 	 */
254 	drm_WARN_ON(dev, startadd > 0x1fffff);
255 
256 	RREG_ECRT(0x00, crtcext0);
257 
258 	crtcc = (startadd >> 8) & 0xff;
259 	crtcd = startadd & 0xff;
260 	crtcext0 &= 0xb0;
261 	crtcext0 |= ((startadd >> 14) & BIT(6)) |
262 		    ((startadd >> 16) & 0x0f);
263 
264 	WREG_CRT(0x0c, crtcc);
265 	WREG_CRT(0x0d, crtcd);
266 	WREG_ECRT(0x00, crtcext0);
267 }
268 
269 static void mgag200_set_dac_regs(struct mga_device *mdev)
270 {
271 	size_t i;
272 	u8 dacvalue[] = {
273 		/* 0x00: */        0,    0,    0,    0,    0,    0, 0x00,    0,
274 		/* 0x08: */        0,    0,    0,    0,    0,    0,    0,    0,
275 		/* 0x10: */        0,    0,    0,    0,    0,    0,    0,    0,
276 		/* 0x18: */     0x00,    0, 0xC9, 0xFF, 0xBF, 0x20, 0x1F, 0x20,
277 		/* 0x20: */     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
278 		/* 0x28: */     0x00, 0x00, 0x00, 0x00,    0,    0,    0, 0x40,
279 		/* 0x30: */     0x00, 0xB0, 0x00, 0xC2, 0x34, 0x14, 0x02, 0x83,
280 		/* 0x38: */     0x00, 0x93, 0x00, 0x77, 0x00, 0x00, 0x00, 0x3A,
281 		/* 0x40: */        0,    0,    0,    0,    0,    0,    0,    0,
282 		/* 0x48: */        0,    0,    0,    0,    0,    0,    0,    0
283 	};
284 
285 	switch (mdev->type) {
286 	case G200_PCI:
287 	case G200_AGP:
288 		dacvalue[MGA1064_SYS_PLL_M] = 0x04;
289 		dacvalue[MGA1064_SYS_PLL_N] = 0x2D;
290 		dacvalue[MGA1064_SYS_PLL_P] = 0x19;
291 		break;
292 	case G200_SE_A:
293 	case G200_SE_B:
294 		dacvalue[MGA1064_VREF_CTL] = 0x03;
295 		dacvalue[MGA1064_PIX_CLK_CTL] = MGA1064_PIX_CLK_CTL_SEL_PLL;
296 		dacvalue[MGA1064_MISC_CTL] = MGA1064_MISC_CTL_DAC_EN |
297 					     MGA1064_MISC_CTL_VGA8 |
298 					     MGA1064_MISC_CTL_DAC_RAM_CS;
299 		break;
300 	case G200_WB:
301 	case G200_EW3:
302 		dacvalue[MGA1064_VREF_CTL] = 0x07;
303 		break;
304 	case G200_EV:
305 		dacvalue[MGA1064_PIX_CLK_CTL] = MGA1064_PIX_CLK_CTL_SEL_PLL;
306 		dacvalue[MGA1064_MISC_CTL] = MGA1064_MISC_CTL_VGA8 |
307 					     MGA1064_MISC_CTL_DAC_RAM_CS;
308 		break;
309 	case G200_EH:
310 	case G200_EH3:
311 		dacvalue[MGA1064_MISC_CTL] = MGA1064_MISC_CTL_VGA8 |
312 					     MGA1064_MISC_CTL_DAC_RAM_CS;
313 		break;
314 	case G200_ER:
315 		break;
316 	}
317 
318 	for (i = 0; i < ARRAY_SIZE(dacvalue); i++) {
319 		if ((i <= 0x17) ||
320 		    (i == 0x1b) ||
321 		    (i == 0x1c) ||
322 		    ((i >= 0x1f) && (i <= 0x29)) ||
323 		    ((i >= 0x30) && (i <= 0x37)))
324 			continue;
325 		if (IS_G200_SE(mdev) &&
326 		    ((i == 0x2c) || (i == 0x2d) || (i == 0x2e)))
327 			continue;
328 		if ((mdev->type == G200_EV ||
329 		    mdev->type == G200_WB ||
330 		    mdev->type == G200_EH ||
331 		    mdev->type == G200_EW3 ||
332 		    mdev->type == G200_EH3) &&
333 		    (i >= 0x44) && (i <= 0x4e))
334 			continue;
335 
336 		WREG_DAC(i, dacvalue[i]);
337 	}
338 
339 	if (mdev->type == G200_ER)
340 		WREG_DAC(0x90, 0);
341 }
342 
343 static void mgag200_init_regs(struct mga_device *mdev)
344 {
345 	u8 crtc11, misc;
346 
347 	mgag200_set_dac_regs(mdev);
348 
349 	WREG_SEQ(2, 0x0f);
350 	WREG_SEQ(3, 0x00);
351 	WREG_SEQ(4, 0x0e);
352 
353 	WREG_CRT(10, 0);
354 	WREG_CRT(11, 0);
355 	WREG_CRT(12, 0);
356 	WREG_CRT(13, 0);
357 	WREG_CRT(14, 0);
358 	WREG_CRT(15, 0);
359 
360 	RREG_CRT(0x11, crtc11);
361 	crtc11 &= ~(MGAREG_CRTC11_CRTCPROTECT |
362 		    MGAREG_CRTC11_VINTEN |
363 		    MGAREG_CRTC11_VINTCLR);
364 	WREG_CRT(0x11, crtc11);
365 
366 	if (mdev->type == G200_ER)
367 		WREG_ECRT(0x24, 0x5);
368 
369 	if (mdev->type == G200_EW3)
370 		WREG_ECRT(0x34, 0x5);
371 
372 	misc = RREG8(MGA_MISC_IN);
373 	misc |= MGAREG_MISC_IOADSEL;
374 	WREG8(MGA_MISC_OUT, misc);
375 }
376 
377 static void mgag200_set_mode_regs(struct mga_device *mdev,
378 				  const struct drm_display_mode *mode)
379 {
380 	const struct mgag200_device_info *info = mdev->info;
381 	unsigned int hdisplay, hsyncstart, hsyncend, htotal;
382 	unsigned int vdisplay, vsyncstart, vsyncend, vtotal;
383 	u8 misc, crtcext1, crtcext2, crtcext5;
384 
385 	hdisplay = mode->hdisplay / 8 - 1;
386 	hsyncstart = mode->hsync_start / 8 - 1;
387 	hsyncend = mode->hsync_end / 8 - 1;
388 	htotal = mode->htotal / 8 - 1;
389 
390 	/* Work around hardware quirk */
391 	if ((htotal & 0x07) == 0x06 || (htotal & 0x07) == 0x04)
392 		htotal++;
393 
394 	vdisplay = mode->vdisplay - 1;
395 	vsyncstart = mode->vsync_start - 1;
396 	vsyncend = mode->vsync_end - 1;
397 	vtotal = mode->vtotal - 2;
398 
399 	misc = RREG8(MGA_MISC_IN);
400 
401 	if (mode->flags & DRM_MODE_FLAG_NHSYNC)
402 		misc |= MGAREG_MISC_HSYNCPOL;
403 	else
404 		misc &= ~MGAREG_MISC_HSYNCPOL;
405 
406 	if (mode->flags & DRM_MODE_FLAG_NVSYNC)
407 		misc |= MGAREG_MISC_VSYNCPOL;
408 	else
409 		misc &= ~MGAREG_MISC_VSYNCPOL;
410 
411 	crtcext1 = (((htotal - 4) & 0x100) >> 8) |
412 		   ((hdisplay & 0x100) >> 7) |
413 		   ((hsyncstart & 0x100) >> 6) |
414 		    (htotal & 0x40);
415 	if (info->has_vidrst)
416 		crtcext1 |= MGAREG_CRTCEXT1_VRSTEN |
417 			    MGAREG_CRTCEXT1_HRSTEN;
418 
419 	crtcext2 = ((vtotal & 0xc00) >> 10) |
420 		   ((vdisplay & 0x400) >> 8) |
421 		   ((vdisplay & 0xc00) >> 7) |
422 		   ((vsyncstart & 0xc00) >> 5) |
423 		   ((vdisplay & 0x400) >> 3);
424 	crtcext5 = 0x00;
425 
426 	WREG_CRT(0, htotal - 4);
427 	WREG_CRT(1, hdisplay);
428 	WREG_CRT(2, hdisplay);
429 	WREG_CRT(3, (htotal & 0x1F) | 0x80);
430 	WREG_CRT(4, hsyncstart);
431 	WREG_CRT(5, ((htotal & 0x20) << 2) | (hsyncend & 0x1F));
432 	WREG_CRT(6, vtotal & 0xFF);
433 	WREG_CRT(7, ((vtotal & 0x100) >> 8) |
434 		 ((vdisplay & 0x100) >> 7) |
435 		 ((vsyncstart & 0x100) >> 6) |
436 		 ((vdisplay & 0x100) >> 5) |
437 		 ((vdisplay & 0x100) >> 4) | /* linecomp */
438 		 ((vtotal & 0x200) >> 4) |
439 		 ((vdisplay & 0x200) >> 3) |
440 		 ((vsyncstart & 0x200) >> 2));
441 	WREG_CRT(9, ((vdisplay & 0x200) >> 4) |
442 		 ((vdisplay & 0x200) >> 3));
443 	WREG_CRT(16, vsyncstart & 0xFF);
444 	WREG_CRT(17, (vsyncend & 0x0F) | 0x20);
445 	WREG_CRT(18, vdisplay & 0xFF);
446 	WREG_CRT(20, 0);
447 	WREG_CRT(21, vdisplay & 0xFF);
448 	WREG_CRT(22, (vtotal + 1) & 0xFF);
449 	WREG_CRT(23, 0xc3);
450 	WREG_CRT(24, vdisplay & 0xFF);
451 
452 	WREG_ECRT(0x01, crtcext1);
453 	WREG_ECRT(0x02, crtcext2);
454 	WREG_ECRT(0x05, crtcext5);
455 
456 	WREG8(MGA_MISC_OUT, misc);
457 }
458 
459 static u8 mgag200_get_bpp_shift(const struct drm_format_info *format)
460 {
461 	static const u8 bpp_shift[] = {0, 1, 0, 2};
462 
463 	return bpp_shift[format->cpp[0] - 1];
464 }
465 
466 /*
467  * Calculates the HW offset value from the framebuffer's pitch. The
468  * offset is a multiple of the pixel size and depends on the display
469  * format.
470  */
471 static u32 mgag200_calculate_offset(struct mga_device *mdev,
472 				    const struct drm_framebuffer *fb)
473 {
474 	u32 offset = fb->pitches[0] / fb->format->cpp[0];
475 	u8 bppshift = mgag200_get_bpp_shift(fb->format);
476 
477 	if (fb->format->cpp[0] * 8 == 24)
478 		offset = (offset * 3) >> (4 - bppshift);
479 	else
480 		offset = offset >> (4 - bppshift);
481 
482 	return offset;
483 }
484 
485 static void mgag200_set_offset(struct mga_device *mdev,
486 			       const struct drm_framebuffer *fb)
487 {
488 	u8 crtc13, crtcext0;
489 	u32 offset = mgag200_calculate_offset(mdev, fb);
490 
491 	RREG_ECRT(0, crtcext0);
492 
493 	crtc13 = offset & 0xff;
494 
495 	crtcext0 &= ~MGAREG_CRTCEXT0_OFFSET_MASK;
496 	crtcext0 |= (offset >> 4) & MGAREG_CRTCEXT0_OFFSET_MASK;
497 
498 	WREG_CRT(0x13, crtc13);
499 	WREG_ECRT(0x00, crtcext0);
500 }
501 
502 static void mgag200_set_format_regs(struct mga_device *mdev,
503 				    const struct drm_framebuffer *fb)
504 {
505 	struct drm_device *dev = &mdev->base;
506 	const struct drm_format_info *format = fb->format;
507 	unsigned int bpp, bppshift, scale;
508 	u8 crtcext3, xmulctrl;
509 
510 	bpp = format->cpp[0] * 8;
511 
512 	bppshift = mgag200_get_bpp_shift(format);
513 	switch (bpp) {
514 	case 24:
515 		scale = ((1 << bppshift) * 3) - 1;
516 		break;
517 	default:
518 		scale = (1 << bppshift) - 1;
519 		break;
520 	}
521 
522 	RREG_ECRT(3, crtcext3);
523 
524 	switch (bpp) {
525 	case 8:
526 		xmulctrl = MGA1064_MUL_CTL_8bits;
527 		break;
528 	case 16:
529 		if (format->depth == 15)
530 			xmulctrl = MGA1064_MUL_CTL_15bits;
531 		else
532 			xmulctrl = MGA1064_MUL_CTL_16bits;
533 		break;
534 	case 24:
535 		xmulctrl = MGA1064_MUL_CTL_24bits;
536 		break;
537 	case 32:
538 		xmulctrl = MGA1064_MUL_CTL_32_24bits;
539 		break;
540 	default:
541 		/* BUG: We should have caught this problem already. */
542 		drm_WARN_ON(dev, "invalid format depth\n");
543 		return;
544 	}
545 
546 	crtcext3 &= ~GENMASK(2, 0);
547 	crtcext3 |= scale;
548 
549 	WREG_DAC(MGA1064_MUL_CTL, xmulctrl);
550 
551 	WREG_GFX(0, 0x00);
552 	WREG_GFX(1, 0x00);
553 	WREG_GFX(2, 0x00);
554 	WREG_GFX(3, 0x00);
555 	WREG_GFX(4, 0x00);
556 	WREG_GFX(5, 0x40);
557 	/* GCTL6 should be 0x05, but we configure memmapsl to 0xb8000 (text mode),
558 	 * so that it doesn't hang when running kexec/kdump on G200_SE rev42.
559 	 */
560 	WREG_GFX(6, 0x0d);
561 	WREG_GFX(7, 0x0f);
562 	WREG_GFX(8, 0x0f);
563 
564 	WREG_ECRT(3, crtcext3);
565 }
566 
567 static void mgag200_g200er_reset_tagfifo(struct mga_device *mdev)
568 {
569 	static uint32_t RESET_FLAG = 0x00200000; /* undocumented magic value */
570 	u32 memctl;
571 
572 	memctl = RREG32(MGAREG_MEMCTL);
573 
574 	memctl |= RESET_FLAG;
575 	WREG32(MGAREG_MEMCTL, memctl);
576 
577 	udelay(1000);
578 
579 	memctl &= ~RESET_FLAG;
580 	WREG32(MGAREG_MEMCTL, memctl);
581 }
582 
583 static void mgag200_g200se_set_hiprilvl(struct mga_device *mdev,
584 					const struct drm_display_mode *mode,
585 					const struct drm_framebuffer *fb)
586 {
587 	struct mgag200_g200se_device *g200se = to_mgag200_g200se_device(&mdev->base);
588 	unsigned int hiprilvl;
589 	u8 crtcext6;
590 
591 	if  (g200se->unique_rev_id >= 0x04) {
592 		hiprilvl = 0;
593 	} else if (g200se->unique_rev_id >= 0x02) {
594 		unsigned int bpp;
595 		unsigned long mb;
596 
597 		if (fb->format->cpp[0] * 8 > 16)
598 			bpp = 32;
599 		else if (fb->format->cpp[0] * 8 > 8)
600 			bpp = 16;
601 		else
602 			bpp = 8;
603 
604 		mb = (mode->clock * bpp) / 1000;
605 		if (mb > 3100)
606 			hiprilvl = 0;
607 		else if (mb > 2600)
608 			hiprilvl = 1;
609 		else if (mb > 1900)
610 			hiprilvl = 2;
611 		else if (mb > 1160)
612 			hiprilvl = 3;
613 		else if (mb > 440)
614 			hiprilvl = 4;
615 		else
616 			hiprilvl = 5;
617 
618 	} else if (g200se->unique_rev_id >= 0x01) {
619 		hiprilvl = 3;
620 	} else {
621 		hiprilvl = 4;
622 	}
623 
624 	crtcext6 = hiprilvl; /* implicitly sets maxhipri to 0 */
625 
626 	WREG_ECRT(0x06, crtcext6);
627 }
628 
629 static void mgag200_g200ev_set_hiprilvl(struct mga_device *mdev)
630 {
631 	WREG_ECRT(0x06, 0x00);
632 }
633 
634 static void mgag200_enable_display(struct mga_device *mdev)
635 {
636 	u8 seq0, seq1, crtcext1;
637 
638 	RREG_SEQ(0x00, seq0);
639 	seq0 |= MGAREG_SEQ0_SYNCRST |
640 		MGAREG_SEQ0_ASYNCRST;
641 	WREG_SEQ(0x00, seq0);
642 
643 	/*
644 	 * TODO: replace busy waiting with vblank IRQ; put
645 	 *       msleep(50) before changing SCROFF
646 	 */
647 	mga_wait_vsync(mdev);
648 	mga_wait_busy(mdev);
649 
650 	RREG_SEQ(0x01, seq1);
651 	seq1 &= ~MGAREG_SEQ1_SCROFF;
652 	WREG_SEQ(0x01, seq1);
653 
654 	msleep(20);
655 
656 	RREG_ECRT(0x01, crtcext1);
657 	crtcext1 &= ~MGAREG_CRTCEXT1_VSYNCOFF;
658 	crtcext1 &= ~MGAREG_CRTCEXT1_HSYNCOFF;
659 	WREG_ECRT(0x01, crtcext1);
660 }
661 
662 static void mgag200_disable_display(struct mga_device *mdev)
663 {
664 	u8 seq0, seq1, crtcext1;
665 
666 	RREG_SEQ(0x00, seq0);
667 	seq0 &= ~MGAREG_SEQ0_SYNCRST;
668 	WREG_SEQ(0x00, seq0);
669 
670 	/*
671 	 * TODO: replace busy waiting with vblank IRQ; put
672 	 *       msleep(50) before changing SCROFF
673 	 */
674 	mga_wait_vsync(mdev);
675 	mga_wait_busy(mdev);
676 
677 	RREG_SEQ(0x01, seq1);
678 	seq1 |= MGAREG_SEQ1_SCROFF;
679 	WREG_SEQ(0x01, seq1);
680 
681 	msleep(20);
682 
683 	RREG_ECRT(0x01, crtcext1);
684 	crtcext1 |= MGAREG_CRTCEXT1_VSYNCOFF |
685 		    MGAREG_CRTCEXT1_HSYNCOFF;
686 	WREG_ECRT(0x01, crtcext1);
687 }
688 
689 /*
690  * Connector
691  */
692 
693 static int mgag200_vga_connector_helper_get_modes(struct drm_connector *connector)
694 {
695 	struct mga_device *mdev = to_mga_device(connector->dev);
696 	int ret;
697 
698 	/*
699 	 * Protect access to I/O registers from concurrent modesetting
700 	 * by acquiring the I/O-register lock.
701 	 */
702 	mutex_lock(&mdev->rmmio_lock);
703 	ret = drm_connector_helper_get_modes_from_ddc(connector);
704 	mutex_unlock(&mdev->rmmio_lock);
705 
706 	return ret;
707 }
708 
709 static const struct drm_connector_helper_funcs mga_vga_connector_helper_funcs = {
710 	.get_modes  = mgag200_vga_connector_helper_get_modes,
711 };
712 
713 static const struct drm_connector_funcs mga_vga_connector_funcs = {
714 	.reset                  = drm_atomic_helper_connector_reset,
715 	.fill_modes             = drm_helper_probe_single_connector_modes,
716 	.destroy                = drm_connector_cleanup,
717 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
718 	.atomic_destroy_state   = drm_atomic_helper_connector_destroy_state,
719 };
720 
721 /*
722  * Simple Display Pipe
723  */
724 
725 static enum drm_mode_status
726 mgag200_simple_display_pipe_mode_valid(struct drm_simple_display_pipe *pipe,
727 				       const struct drm_display_mode *mode)
728 {
729 	struct mga_device *mdev = to_mga_device(pipe->crtc.dev);
730 	const struct mgag200_device_info *info = mdev->info;
731 
732 	/*
733 	 * Some devices have additional limits on the size of the
734 	 * display mode.
735 	 */
736 	if (mode->hdisplay > info->max_hdisplay)
737 		return MODE_VIRTUAL_X;
738 	if (mode->vdisplay > info->max_vdisplay)
739 		return MODE_VIRTUAL_Y;
740 
741 	if ((mode->hdisplay % 8) != 0 || (mode->hsync_start % 8) != 0 ||
742 	    (mode->hsync_end % 8) != 0 || (mode->htotal % 8) != 0) {
743 		return MODE_H_ILLEGAL;
744 	}
745 
746 	if (mode->crtc_hdisplay > 2048 || mode->crtc_hsync_start > 4096 ||
747 	    mode->crtc_hsync_end > 4096 || mode->crtc_htotal > 4096 ||
748 	    mode->crtc_vdisplay > 2048 || mode->crtc_vsync_start > 4096 ||
749 	    mode->crtc_vsync_end > 4096 || mode->crtc_vtotal > 4096) {
750 		return MODE_BAD;
751 	}
752 
753 	return MODE_OK;
754 }
755 
756 static void
757 mgag200_handle_damage(struct mga_device *mdev, struct drm_framebuffer *fb,
758 		      struct drm_rect *clip, const struct iosys_map *map)
759 {
760 	void __iomem *dst = mdev->vram;
761 	void *vmap = map->vaddr; /* TODO: Use mapping abstraction properly */
762 
763 	dst += drm_fb_clip_offset(fb->pitches[0], fb->format, clip);
764 	drm_fb_memcpy_toio(dst, fb->pitches[0], vmap, fb, clip);
765 }
766 
767 static void
768 mgag200_simple_display_pipe_enable(struct drm_simple_display_pipe *pipe,
769 				   struct drm_crtc_state *crtc_state,
770 				   struct drm_plane_state *plane_state)
771 {
772 	struct drm_crtc *crtc = &pipe->crtc;
773 	struct drm_device *dev = crtc->dev;
774 	struct mga_device *mdev = to_mga_device(dev);
775 	struct mgag200_pll *pixpll = &mdev->pixpll;
776 	struct drm_display_mode *adjusted_mode = &crtc_state->adjusted_mode;
777 	struct mgag200_crtc_state *mgag200_crtc_state = to_mgag200_crtc_state(crtc_state);
778 	struct drm_framebuffer *fb = plane_state->fb;
779 	struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);
780 	struct drm_rect fullscreen = {
781 		.x1 = 0,
782 		.x2 = fb->width,
783 		.y1 = 0,
784 		.y2 = fb->height,
785 	};
786 
787 	/*
788 	 * Concurrent operations could possibly trigger a call to
789 	 * drm_connector_helper_funcs.get_modes by trying to read the
790 	 * display modes. Protect access to I/O registers by acquiring
791 	 * the I/O-register lock.
792 	 */
793 	mutex_lock(&mdev->rmmio_lock);
794 
795 	if (mdev->type == G200_WB || mdev->type == G200_EW3)
796 		mgag200_g200wb_hold_bmc(mdev);
797 
798 	mgag200_set_format_regs(mdev, fb);
799 	mgag200_set_mode_regs(mdev, adjusted_mode);
800 
801 	pixpll->funcs->update(pixpll, &mgag200_crtc_state->pixpllc);
802 
803 	if (mdev->type == G200_ER)
804 		mgag200_g200er_reset_tagfifo(mdev);
805 
806 	if (IS_G200_SE(mdev))
807 		mgag200_g200se_set_hiprilvl(mdev, adjusted_mode, fb);
808 	else if (mdev->type == G200_EV)
809 		mgag200_g200ev_set_hiprilvl(mdev);
810 
811 	if (mdev->type == G200_WB || mdev->type == G200_EW3)
812 		mgag200_g200wb_release_bmc(mdev);
813 
814 	if (crtc_state->gamma_lut)
815 		mgag200_crtc_set_gamma(mdev, fb->format, crtc_state->gamma_lut->data);
816 	else
817 		mgag200_crtc_set_gamma_linear(mdev, fb->format);
818 
819 	mgag200_enable_display(mdev);
820 
821 	mgag200_handle_damage(mdev, fb, &fullscreen, &shadow_plane_state->data[0]);
822 
823 	/* Always scanout image at VRAM offset 0 */
824 	mgag200_set_startadd(mdev, (u32)0);
825 	mgag200_set_offset(mdev, fb);
826 
827 	mutex_unlock(&mdev->rmmio_lock);
828 }
829 
830 static void
831 mgag200_simple_display_pipe_disable(struct drm_simple_display_pipe *pipe)
832 {
833 	struct drm_crtc *crtc = &pipe->crtc;
834 	struct mga_device *mdev = to_mga_device(crtc->dev);
835 
836 	mgag200_disable_display(mdev);
837 }
838 
839 static int
840 mgag200_simple_display_pipe_check(struct drm_simple_display_pipe *pipe,
841 				  struct drm_plane_state *plane_state,
842 				  struct drm_crtc_state *crtc_state)
843 {
844 	struct drm_plane *plane = plane_state->plane;
845 	struct drm_device *dev = plane->dev;
846 	struct mga_device *mdev = to_mga_device(dev);
847 	struct mgag200_pll *pixpll = &mdev->pixpll;
848 	struct mgag200_crtc_state *mgag200_crtc_state = to_mgag200_crtc_state(crtc_state);
849 	struct drm_framebuffer *new_fb = plane_state->fb;
850 	struct drm_framebuffer *fb = NULL;
851 	int ret;
852 
853 	if (!new_fb)
854 		return 0;
855 
856 	if (plane->state)
857 		fb = plane->state->fb;
858 
859 	if (!fb || (fb->format != new_fb->format))
860 		crtc_state->mode_changed = true; /* update PLL settings */
861 
862 	if (crtc_state->mode_changed) {
863 		ret = pixpll->funcs->compute(pixpll, crtc_state->mode.clock,
864 					     &mgag200_crtc_state->pixpllc);
865 		if (ret)
866 			return ret;
867 	}
868 
869 	if (crtc_state->color_mgmt_changed && crtc_state->gamma_lut) {
870 		if (crtc_state->gamma_lut->length !=
871 		    MGAG200_LUT_SIZE * sizeof(struct drm_color_lut)) {
872 			drm_err(dev, "Wrong size for gamma_lut %zu\n",
873 				crtc_state->gamma_lut->length);
874 			return -EINVAL;
875 		}
876 	}
877 	return 0;
878 }
879 
880 static void
881 mgag200_simple_display_pipe_update(struct drm_simple_display_pipe *pipe,
882 				   struct drm_plane_state *old_state)
883 {
884 	struct drm_plane *plane = &pipe->plane;
885 	struct drm_crtc *crtc = &pipe->crtc;
886 	struct drm_device *dev = plane->dev;
887 	struct mga_device *mdev = to_mga_device(dev);
888 	struct drm_plane_state *state = plane->state;
889 	struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(state);
890 	struct drm_framebuffer *fb = state->fb;
891 	struct drm_rect damage;
892 	struct drm_atomic_helper_damage_iter iter;
893 
894 	if (!fb)
895 		return;
896 
897 	mutex_lock(&mdev->rmmio_lock);
898 
899 	if (crtc->state->color_mgmt_changed && crtc->state->gamma_lut)
900 		mgag200_crtc_set_gamma(mdev, fb->format, crtc->state->gamma_lut->data);
901 
902 	drm_atomic_helper_damage_iter_init(&iter, old_state, state);
903 	drm_atomic_for_each_plane_damage(&iter, &damage) {
904 		mgag200_handle_damage(mdev, fb, &damage, &shadow_plane_state->data[0]);
905 	}
906 	/* Always scanout image at VRAM offset 0 */
907 	mgag200_set_startadd(mdev, (u32)0);
908 	mgag200_set_offset(mdev, fb);
909 
910 	mutex_unlock(&mdev->rmmio_lock);
911 }
912 
913 static struct drm_crtc_state *
914 mgag200_simple_display_pipe_duplicate_crtc_state(struct drm_simple_display_pipe *pipe)
915 {
916 	struct drm_crtc *crtc = &pipe->crtc;
917 	struct drm_crtc_state *crtc_state = crtc->state;
918 	struct mgag200_crtc_state *mgag200_crtc_state = to_mgag200_crtc_state(crtc_state);
919 	struct mgag200_crtc_state *new_mgag200_crtc_state;
920 
921 	if (!crtc_state)
922 		return NULL;
923 
924 	new_mgag200_crtc_state = kzalloc(sizeof(*new_mgag200_crtc_state), GFP_KERNEL);
925 	if (!new_mgag200_crtc_state)
926 		return NULL;
927 	__drm_atomic_helper_crtc_duplicate_state(crtc, &new_mgag200_crtc_state->base);
928 
929 	memcpy(&new_mgag200_crtc_state->pixpllc, &mgag200_crtc_state->pixpllc,
930 	       sizeof(new_mgag200_crtc_state->pixpllc));
931 
932 	return &new_mgag200_crtc_state->base;
933 }
934 
935 static void mgag200_simple_display_pipe_destroy_crtc_state(struct drm_simple_display_pipe *pipe,
936 							   struct drm_crtc_state *crtc_state)
937 {
938 	struct mgag200_crtc_state *mgag200_crtc_state = to_mgag200_crtc_state(crtc_state);
939 
940 	__drm_atomic_helper_crtc_destroy_state(&mgag200_crtc_state->base);
941 	kfree(mgag200_crtc_state);
942 }
943 
944 static void mgag200_simple_display_pipe_reset_crtc(struct drm_simple_display_pipe *pipe)
945 {
946 	struct drm_crtc *crtc = &pipe->crtc;
947 	struct mgag200_crtc_state *mgag200_crtc_state;
948 
949 	if (crtc->state) {
950 		mgag200_simple_display_pipe_destroy_crtc_state(pipe, crtc->state);
951 		crtc->state = NULL; /* must be set to NULL here */
952 	}
953 
954 	mgag200_crtc_state = kzalloc(sizeof(*mgag200_crtc_state), GFP_KERNEL);
955 	if (!mgag200_crtc_state)
956 		return;
957 	__drm_atomic_helper_crtc_reset(crtc, &mgag200_crtc_state->base);
958 }
959 
960 static const struct drm_simple_display_pipe_funcs
961 mgag200_simple_display_pipe_funcs = {
962 	.mode_valid = mgag200_simple_display_pipe_mode_valid,
963 	.enable	    = mgag200_simple_display_pipe_enable,
964 	.disable    = mgag200_simple_display_pipe_disable,
965 	.check	    = mgag200_simple_display_pipe_check,
966 	.update	    = mgag200_simple_display_pipe_update,
967 	.reset_crtc = mgag200_simple_display_pipe_reset_crtc,
968 	.duplicate_crtc_state = mgag200_simple_display_pipe_duplicate_crtc_state,
969 	.destroy_crtc_state = mgag200_simple_display_pipe_destroy_crtc_state,
970 	DRM_GEM_SIMPLE_DISPLAY_PIPE_SHADOW_PLANE_FUNCS,
971 };
972 
973 static const uint32_t mgag200_simple_display_pipe_formats[] = {
974 	DRM_FORMAT_XRGB8888,
975 	DRM_FORMAT_RGB565,
976 	DRM_FORMAT_RGB888,
977 };
978 
979 static const uint64_t mgag200_simple_display_pipe_fmtmods[] = {
980 	DRM_FORMAT_MOD_LINEAR,
981 	DRM_FORMAT_MOD_INVALID
982 };
983 
984 /*
985  * Mode config
986  */
987 
988 /* Calculates a mode's required memory bandwidth (in KiB/sec). */
989 static uint32_t mgag200_calculate_mode_bandwidth(const struct drm_display_mode *mode,
990 						 unsigned int bits_per_pixel)
991 {
992 	uint32_t total_area, divisor;
993 	uint64_t active_area, pixels_per_second, bandwidth;
994 	uint64_t bytes_per_pixel = (bits_per_pixel + 7) / 8;
995 
996 	divisor = 1024;
997 
998 	if (!mode->htotal || !mode->vtotal || !mode->clock)
999 		return 0;
1000 
1001 	active_area = mode->hdisplay * mode->vdisplay;
1002 	total_area = mode->htotal * mode->vtotal;
1003 
1004 	pixels_per_second = active_area * mode->clock * 1000;
1005 	do_div(pixels_per_second, total_area);
1006 
1007 	bandwidth = pixels_per_second * bytes_per_pixel * 100;
1008 	do_div(bandwidth, divisor);
1009 
1010 	return (uint32_t)bandwidth;
1011 }
1012 
1013 static enum drm_mode_status mgag200_mode_config_mode_valid(struct drm_device *dev,
1014 							   const struct drm_display_mode *mode)
1015 {
1016 	static const unsigned int max_bpp = 4; // DRM_FORMAT_XRGB8888
1017 	struct mga_device *mdev = to_mga_device(dev);
1018 	unsigned long fbsize, fbpages, max_fbpages;
1019 	const struct mgag200_device_info *info = mdev->info;
1020 
1021 	max_fbpages = mdev->vram_available >> PAGE_SHIFT;
1022 
1023 	fbsize = mode->hdisplay * mode->vdisplay * max_bpp;
1024 	fbpages = DIV_ROUND_UP(fbsize, PAGE_SIZE);
1025 
1026 	if (fbpages > max_fbpages)
1027 		return MODE_MEM;
1028 
1029 	/*
1030 	 * Test the mode's required memory bandwidth if the device
1031 	 * specifies a maximum. Not all devices do though.
1032 	 */
1033 	if (info->max_mem_bandwidth) {
1034 		uint32_t mode_bandwidth = mgag200_calculate_mode_bandwidth(mode, max_bpp * 8);
1035 
1036 		if (mode_bandwidth > (info->max_mem_bandwidth * 1024))
1037 			return MODE_BAD;
1038 	}
1039 
1040 	return MODE_OK;
1041 }
1042 
1043 static const struct drm_mode_config_funcs mgag200_mode_config_funcs = {
1044 	.fb_create = drm_gem_fb_create_with_dirty,
1045 	.mode_valid = mgag200_mode_config_mode_valid,
1046 	.atomic_check = drm_atomic_helper_check,
1047 	.atomic_commit = drm_atomic_helper_commit,
1048 };
1049 
1050 int mgag200_modeset_init(struct mga_device *mdev, resource_size_t vram_available)
1051 {
1052 	struct drm_device *dev = &mdev->base;
1053 	struct mga_i2c_chan *i2c = &mdev->i2c;
1054 	struct drm_connector *connector = &mdev->connector;
1055 	struct drm_simple_display_pipe *pipe = &mdev->display_pipe;
1056 	size_t format_count = ARRAY_SIZE(mgag200_simple_display_pipe_formats);
1057 	int ret;
1058 
1059 	mgag200_init_regs(mdev);
1060 
1061 	mdev->vram_available = vram_available;
1062 
1063 	ret = drmm_mode_config_init(dev);
1064 	if (ret) {
1065 		drm_err(dev, "drmm_mode_config_init() failed, error %d\n",
1066 			ret);
1067 		return ret;
1068 	}
1069 
1070 	dev->mode_config.max_width = MGAG200_MAX_FB_WIDTH;
1071 	dev->mode_config.max_height = MGAG200_MAX_FB_HEIGHT;
1072 	dev->mode_config.preferred_depth = 24;
1073 	dev->mode_config.fb_base = mdev->vram_res->start;
1074 	dev->mode_config.funcs = &mgag200_mode_config_funcs;
1075 
1076 	ret = mgag200_i2c_init(mdev, i2c);
1077 	if (ret) {
1078 		drm_err(dev, "failed to add DDC bus: %d\n", ret);
1079 		return ret;
1080 	}
1081 
1082 	ret = drm_connector_init_with_ddc(dev, connector,
1083 					  &mga_vga_connector_funcs,
1084 					  DRM_MODE_CONNECTOR_VGA,
1085 					  &i2c->adapter);
1086 	if (ret) {
1087 		drm_err(dev, "drm_connector_init_with_ddc() failed: %d\n", ret);
1088 		return ret;
1089 	}
1090 	drm_connector_helper_add(connector, &mga_vga_connector_helper_funcs);
1091 
1092 	ret = mgag200_pixpll_init(&mdev->pixpll, mdev);
1093 	if (ret)
1094 		return ret;
1095 
1096 	ret = drm_simple_display_pipe_init(dev, pipe,
1097 					   &mgag200_simple_display_pipe_funcs,
1098 					   mgag200_simple_display_pipe_formats,
1099 					   format_count,
1100 					   mgag200_simple_display_pipe_fmtmods,
1101 					   connector);
1102 	if (ret) {
1103 		drm_err(dev,
1104 			"drm_simple_display_pipe_init() failed, error %d\n",
1105 			ret);
1106 		return ret;
1107 	}
1108 
1109 	drm_plane_enable_fb_damage_clips(&pipe->plane);
1110 
1111 	/* FIXME: legacy gamma tables, but atomic gamma doesn't work without */
1112 	drm_mode_crtc_set_gamma_size(&pipe->crtc, MGAG200_LUT_SIZE);
1113 
1114 	drm_crtc_enable_color_mgmt(&pipe->crtc, 0, false, MGAG200_LUT_SIZE);
1115 
1116 	drm_mode_config_reset(dev);
1117 
1118 	return 0;
1119 }
1120