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Get rid of 'remove_new' relic from platform driver struct
[linux.git] / drivers / gpu / drm / vc4 / vc4_hvs.c
blob70623e6b91e9f5ba2e9052da437c362c32c0ac60
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2015 Broadcom
4 */
5
6 /**
7 * DOC: VC4 HVS module.
8 *
9 * The Hardware Video Scaler (HVS) is the piece of hardware that does
10 * translation, scaling, colorspace conversion, and compositing of
11 * pixels stored in framebuffers into a FIFO of pixels going out to
12 * the Pixel Valve (CRTC). It operates at the system clock rate (the
13 * system audio clock gate, specifically), which is much higher than
14 * the pixel clock rate.
15 *
16 * There is a single global HVS, with multiple output FIFOs that can
17 * be consumed by the PVs. This file just manages the resources for
18 * the HVS, while the vc4_crtc.c code actually drives HVS setup for
19 * each CRTC.
20 */
21
22 #include <linux/bitfield.h>
23 #include <linux/clk.h>
24 #include <linux/component.h>
25 #include <linux/platform_device.h>
26
27 #include <drm/drm_atomic_helper.h>
28 #include <drm/drm_drv.h>
29 #include <drm/drm_vblank.h>
30
31 #include <soc/bcm2835/raspberrypi-firmware.h>
32
33 #include "vc4_drv.h"
34 #include "vc4_regs.h"
35
36 static const struct debugfs_reg32 vc4_hvs_regs[] = {
37 VC4_REG32(SCALER_DISPCTRL),
38 VC4_REG32(SCALER_DISPSTAT),
39 VC4_REG32(SCALER_DISPID),
40 VC4_REG32(SCALER_DISPECTRL),
41 VC4_REG32(SCALER_DISPPROF),
42 VC4_REG32(SCALER_DISPDITHER),
43 VC4_REG32(SCALER_DISPEOLN),
44 VC4_REG32(SCALER_DISPLIST0),
45 VC4_REG32(SCALER_DISPLIST1),
46 VC4_REG32(SCALER_DISPLIST2),
47 VC4_REG32(SCALER_DISPLSTAT),
48 VC4_REG32(SCALER_DISPLACT0),
49 VC4_REG32(SCALER_DISPLACT1),
50 VC4_REG32(SCALER_DISPLACT2),
51 VC4_REG32(SCALER_DISPCTRL0),
52 VC4_REG32(SCALER_DISPBKGND0),
53 VC4_REG32(SCALER_DISPSTAT0),
54 VC4_REG32(SCALER_DISPBASE0),
55 VC4_REG32(SCALER_DISPCTRL1),
56 VC4_REG32(SCALER_DISPBKGND1),
57 VC4_REG32(SCALER_DISPSTAT1),
58 VC4_REG32(SCALER_DISPBASE1),
59 VC4_REG32(SCALER_DISPCTRL2),
60 VC4_REG32(SCALER_DISPBKGND2),
61 VC4_REG32(SCALER_DISPSTAT2),
62 VC4_REG32(SCALER_DISPBASE2),
63 VC4_REG32(SCALER_DISPALPHA2),
64 VC4_REG32(SCALER_OLEDOFFS),
65 VC4_REG32(SCALER_OLEDCOEF0),
66 VC4_REG32(SCALER_OLEDCOEF1),
67 VC4_REG32(SCALER_OLEDCOEF2),
68 };
69
70 void vc4_hvs_dump_state(struct vc4_hvs *hvs)
71 {
72 struct drm_device *drm = &hvs->vc4->base;
73 struct drm_printer p = drm_info_printer(&hvs->pdev->dev);
74 int idx, i;
75
76 if (!drm_dev_enter(drm, &idx))
77 return;
78
79 drm_print_regset32(&p, &hvs->regset);
80
81 DRM_INFO("HVS ctx:\n");
82 for (i = 0; i < 64; i += 4) {
83 DRM_INFO("0x%08x (%s): 0x%08x 0x%08x 0x%08x 0x%08x\n",
84 i * 4, i < HVS_BOOTLOADER_DLIST_END ? "B" : "D",
85 readl((u32 __iomem *)hvs->dlist + i + 0),
86 readl((u32 __iomem *)hvs->dlist + i + 1),
87 readl((u32 __iomem *)hvs->dlist + i + 2),
88 readl((u32 __iomem *)hvs->dlist + i + 3));
89 }
90
91 drm_dev_exit(idx);
92 }
93
94 static int vc4_hvs_debugfs_underrun(struct seq_file *m, void *data)
95 {
96 struct drm_debugfs_entry *entry = m->private;
97 struct drm_device *dev = entry->dev;
98 struct vc4_dev *vc4 = to_vc4_dev(dev);
99 struct drm_printer p = drm_seq_file_printer(m);
100
101 drm_printf(&p, "%d\n", atomic_read(&vc4->underrun));
102
103 return 0;
104 }
105
106 static int vc4_hvs_debugfs_dlist(struct seq_file *m, void *data)
107 {
108 struct drm_debugfs_entry *entry = m->private;
109 struct drm_device *dev = entry->dev;
110 struct vc4_dev *vc4 = to_vc4_dev(dev);
111 struct vc4_hvs *hvs = vc4->hvs;
112 struct drm_printer p = drm_seq_file_printer(m);
113 unsigned int dlist_mem_size = hvs->dlist_mem_size;
114 unsigned int next_entry_start;
115 unsigned int i, j;
116 u32 dlist_word, dispstat;
117
118 for (i = 0; i < SCALER_CHANNELS_COUNT; i++) {
119 dispstat = VC4_GET_FIELD(HVS_READ(SCALER_DISPSTATX(i)),
120 SCALER_DISPSTATX_MODE);
121 if (dispstat == SCALER_DISPSTATX_MODE_DISABLED ||
122 dispstat == SCALER_DISPSTATX_MODE_EOF) {
123 drm_printf(&p, "HVS chan %u disabled\n", i);
124 continue;
125 }
126
127 drm_printf(&p, "HVS chan %u:\n", i);
128 next_entry_start = 0;
129
130 for (j = HVS_READ(SCALER_DISPLISTX(i)); j < dlist_mem_size; j++) {
131 dlist_word = readl((u32 __iomem *)vc4->hvs->dlist + j);
132 drm_printf(&p, "dlist: %02d: 0x%08x\n", j,
133 dlist_word);
134 if (!next_entry_start ||
135 next_entry_start == j) {
136 if (dlist_word & SCALER_CTL0_END)
137 break;
138 next_entry_start = j +
139 VC4_GET_FIELD(dlist_word,
140 SCALER_CTL0_SIZE);
141 }
142 }
143 }
144
145 return 0;
146 }
147
148 /* The filter kernel is composed of dwords each containing 3 9-bit
149 * signed integers packed next to each other.
150 */
151 #define VC4_INT_TO_COEFF(coeff) (coeff & 0x1ff)
152 #define VC4_PPF_FILTER_WORD(c0, c1, c2) \
153 ((((c0) & 0x1ff) << 0) | \
154 (((c1) & 0x1ff) << 9) | \
155 (((c2) & 0x1ff) << 18))
156
157 /* The whole filter kernel is arranged as the coefficients 0-16 going
158 * up, then a pad, then 17-31 going down and reversed within the
159 * dwords. This means that a linear phase kernel (where it's
160 * symmetrical at the boundary between 15 and 16) has the last 5
161 * dwords matching the first 5, but reversed.
162 */
163 #define VC4_LINEAR_PHASE_KERNEL(c0, c1, c2, c3, c4, c5, c6, c7, c8, \
164 c9, c10, c11, c12, c13, c14, c15) \
165 {VC4_PPF_FILTER_WORD(c0, c1, c2), \
166 VC4_PPF_FILTER_WORD(c3, c4, c5), \
167 VC4_PPF_FILTER_WORD(c6, c7, c8), \
168 VC4_PPF_FILTER_WORD(c9, c10, c11), \
169 VC4_PPF_FILTER_WORD(c12, c13, c14), \
170 VC4_PPF_FILTER_WORD(c15, c15, 0)}
171
172 #define VC4_LINEAR_PHASE_KERNEL_DWORDS 6
173 #define VC4_KERNEL_DWORDS (VC4_LINEAR_PHASE_KERNEL_DWORDS * 2 - 1)
174
175 /* Recommended B=1/3, C=1/3 filter choice from Mitchell/Netravali.
176 * http://www.cs.utexas.edu/~fussell/courses/cs384g/lectures/mitchell/Mitchell.pdf
177 */
178 static const u32 mitchell_netravali_1_3_1_3_kernel[] =
179 VC4_LINEAR_PHASE_KERNEL(0, -2, -6, -8, -10, -8, -3, 2, 18,
180 50, 82, 119, 155, 187, 213, 227);
181
182 static int vc4_hvs_upload_linear_kernel(struct vc4_hvs *hvs,
183 struct drm_mm_node *space,
184 const u32 *kernel)
185 {
186 int ret, i;
187 u32 __iomem *dst_kernel;
188
189 /*
190 * NOTE: We don't need a call to drm_dev_enter()/drm_dev_exit()
191 * here since that function is only called from vc4_hvs_bind().
192 */
193
194 ret = drm_mm_insert_node(&hvs->dlist_mm, space, VC4_KERNEL_DWORDS);
195 if (ret) {
196 drm_err(&hvs->vc4->base, "Failed to allocate space for filter kernel: %d\n",
197 ret);
198 return ret;
199 }
200
201 dst_kernel = hvs->dlist + space->start;
202
203 for (i = 0; i < VC4_KERNEL_DWORDS; i++) {
204 if (i < VC4_LINEAR_PHASE_KERNEL_DWORDS)
205 writel(kernel[i], &dst_kernel[i]);
206 else {
207 writel(kernel[VC4_KERNEL_DWORDS - i - 1],
208 &dst_kernel[i]);
209 }
210 }
211
212 return 0;
213 }
214
215 static void vc4_hvs_lut_load(struct vc4_hvs *hvs,
216 struct vc4_crtc *vc4_crtc)
217 {
218 struct drm_device *drm = &hvs->vc4->base;
219 struct drm_crtc *crtc = &vc4_crtc->base;
220 struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
221 int idx;
222 u32 i;
223
224 if (!drm_dev_enter(drm, &idx))
225 return;
226
227 if (hvs->vc4->gen != VC4_GEN_4)
228 goto exit;
229
230 /* The LUT memory is laid out with each HVS channel in order,
231 * each of which takes 256 writes for R, 256 for G, then 256
232 * for B.
233 */
234 HVS_WRITE(SCALER_GAMADDR,
235 SCALER_GAMADDR_AUTOINC |
236 (vc4_state->assigned_channel * 3 * crtc->gamma_size));
237
238 for (i = 0; i < crtc->gamma_size; i++)
239 HVS_WRITE(SCALER_GAMDATA, vc4_crtc->lut_r[i]);
240 for (i = 0; i < crtc->gamma_size; i++)
241 HVS_WRITE(SCALER_GAMDATA, vc4_crtc->lut_g[i]);
242 for (i = 0; i < crtc->gamma_size; i++)
243 HVS_WRITE(SCALER_GAMDATA, vc4_crtc->lut_b[i]);
244
245 exit:
246 drm_dev_exit(idx);
247 }
248
249 static void vc4_hvs_update_gamma_lut(struct vc4_hvs *hvs,
250 struct vc4_crtc *vc4_crtc)
251 {
252 struct drm_crtc_state *crtc_state = vc4_crtc->base.state;
253 struct drm_color_lut *lut = crtc_state->gamma_lut->data;
254 u32 length = drm_color_lut_size(crtc_state->gamma_lut);
255 u32 i;
256
257 for (i = 0; i < length; i++) {
258 vc4_crtc->lut_r[i] = drm_color_lut_extract(lut[i].red, 8);
259 vc4_crtc->lut_g[i] = drm_color_lut_extract(lut[i].green, 8);
260 vc4_crtc->lut_b[i] = drm_color_lut_extract(lut[i].blue, 8);
261 }
262
263 vc4_hvs_lut_load(hvs, vc4_crtc);
264 }
265
266 u8 vc4_hvs_get_fifo_frame_count(struct vc4_hvs *hvs, unsigned int fifo)
267 {
268 struct drm_device *drm = &hvs->vc4->base;
269 u8 field = 0;
270 int idx;
271
272 if (!drm_dev_enter(drm, &idx))
273 return 0;
274
275 switch (fifo) {
276 case 0:
277 field = VC4_GET_FIELD(HVS_READ(SCALER_DISPSTAT1),
278 SCALER_DISPSTAT1_FRCNT0);
279 break;
280 case 1:
281 field = VC4_GET_FIELD(HVS_READ(SCALER_DISPSTAT1),
282 SCALER_DISPSTAT1_FRCNT1);
283 break;
284 case 2:
285 field = VC4_GET_FIELD(HVS_READ(SCALER_DISPSTAT2),
286 SCALER_DISPSTAT2_FRCNT2);
287 break;
288 }
289
290 drm_dev_exit(idx);
291 return field;
292 }
293
294 int vc4_hvs_get_fifo_from_output(struct vc4_hvs *hvs, unsigned int output)
295 {
296 struct vc4_dev *vc4 = hvs->vc4;
297 u32 reg;
298 int ret;
299
300 switch (vc4->gen) {
301 case VC4_GEN_4:
302 return output;
303
304 case VC4_GEN_5:
305 /*
306 * NOTE: We should probably use
307 * drm_dev_enter()/drm_dev_exit() here, but this
308 * function is only used during the DRM device
309 * initialization, so we should be fine.
310 */
311
312 switch (output) {
313 case 0:
314 return 0;
315
316 case 1:
317 return 1;
318
319 case 2:
320 reg = HVS_READ(SCALER_DISPECTRL);
321 ret = FIELD_GET(SCALER_DISPECTRL_DSP2_MUX_MASK, reg);
322 if (ret == 0)
323 return 2;
324
325 return 0;
326
327 case 3:
328 reg = HVS_READ(SCALER_DISPCTRL);
329 ret = FIELD_GET(SCALER_DISPCTRL_DSP3_MUX_MASK, reg);
330 if (ret == 3)
331 return -EPIPE;
332
333 return ret;
334
335 case 4:
336 reg = HVS_READ(SCALER_DISPEOLN);
337 ret = FIELD_GET(SCALER_DISPEOLN_DSP4_MUX_MASK, reg);
338 if (ret == 3)
339 return -EPIPE;
340
341 return ret;
342
343 case 5:
344 reg = HVS_READ(SCALER_DISPDITHER);
345 ret = FIELD_GET(SCALER_DISPDITHER_DSP5_MUX_MASK, reg);
346 if (ret == 3)
347 return -EPIPE;
348
349 return ret;
350
351 default:
352 return -EPIPE;
353 }
354
355 default:
356 return -EPIPE;
357 }
358 }
359
360 static int vc4_hvs_init_channel(struct vc4_hvs *hvs, struct drm_crtc *crtc,
361 struct drm_display_mode *mode, bool oneshot)
362 {
363 struct vc4_dev *vc4 = hvs->vc4;
364 struct drm_device *drm = &vc4->base;
365 struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
366 struct vc4_crtc_state *vc4_crtc_state = to_vc4_crtc_state(crtc->state);
367 unsigned int chan = vc4_crtc_state->assigned_channel;
368 bool interlace = mode->flags & DRM_MODE_FLAG_INTERLACE;
369 u32 dispbkgndx;
370 u32 dispctrl;
371 int idx;
372
373 if (!drm_dev_enter(drm, &idx))
374 return -ENODEV;
375
376 HVS_WRITE(SCALER_DISPCTRLX(chan), 0);
377 HVS_WRITE(SCALER_DISPCTRLX(chan), SCALER_DISPCTRLX_RESET);
378 HVS_WRITE(SCALER_DISPCTRLX(chan), 0);
379
380 /* Turn on the scaler, which will wait for vstart to start
381 * compositing.
382 * When feeding the transposer, we should operate in oneshot
383 * mode.
384 */
385 dispctrl = SCALER_DISPCTRLX_ENABLE;
386 dispbkgndx = HVS_READ(SCALER_DISPBKGNDX(chan));
387
388 if (vc4->gen == VC4_GEN_4) {
389 dispctrl |= VC4_SET_FIELD(mode->hdisplay,
390 SCALER_DISPCTRLX_WIDTH) |
391 VC4_SET_FIELD(mode->vdisplay,
392 SCALER_DISPCTRLX_HEIGHT) |
393 (oneshot ? SCALER_DISPCTRLX_ONESHOT : 0);
394 dispbkgndx |= SCALER_DISPBKGND_AUTOHS;
395 } else {
396 dispctrl |= VC4_SET_FIELD(mode->hdisplay,
397 SCALER5_DISPCTRLX_WIDTH) |
398 VC4_SET_FIELD(mode->vdisplay,
399 SCALER5_DISPCTRLX_HEIGHT) |
400 (oneshot ? SCALER5_DISPCTRLX_ONESHOT : 0);
401 dispbkgndx &= ~SCALER5_DISPBKGND_BCK2BCK;
402 }
403
404 HVS_WRITE(SCALER_DISPCTRLX(chan), dispctrl);
405
406 dispbkgndx &= ~SCALER_DISPBKGND_GAMMA;
407 dispbkgndx &= ~SCALER_DISPBKGND_INTERLACE;
408
409 HVS_WRITE(SCALER_DISPBKGNDX(chan), dispbkgndx |
410 ((vc4->gen == VC4_GEN_4) ? SCALER_DISPBKGND_GAMMA : 0) |
411 (interlace ? SCALER_DISPBKGND_INTERLACE : 0));
412
413 /* Reload the LUT, since the SRAMs would have been disabled if
414 * all CRTCs had SCALER_DISPBKGND_GAMMA unset at once.
415 */
416 vc4_hvs_lut_load(hvs, vc4_crtc);
417
418 drm_dev_exit(idx);
419
420 return 0;
421 }
422
423 void vc4_hvs_stop_channel(struct vc4_hvs *hvs, unsigned int chan)
424 {
425 struct drm_device *drm = &hvs->vc4->base;
426 int idx;
427
428 if (!drm_dev_enter(drm, &idx))
429 return;
430
431 if (!(HVS_READ(SCALER_DISPCTRLX(chan)) & SCALER_DISPCTRLX_ENABLE))
432 goto out;
433
434 HVS_WRITE(SCALER_DISPCTRLX(chan), SCALER_DISPCTRLX_RESET);
435 HVS_WRITE(SCALER_DISPCTRLX(chan), 0);
436
437 /* Once we leave, the scaler should be disabled and its fifo empty. */
438 WARN_ON_ONCE(HVS_READ(SCALER_DISPCTRLX(chan)) & SCALER_DISPCTRLX_RESET);
439
440 WARN_ON_ONCE(VC4_GET_FIELD(HVS_READ(SCALER_DISPSTATX(chan)),
441 SCALER_DISPSTATX_MODE) !=
442 SCALER_DISPSTATX_MODE_DISABLED);
443
444 WARN_ON_ONCE((HVS_READ(SCALER_DISPSTATX(chan)) &
445 (SCALER_DISPSTATX_FULL | SCALER_DISPSTATX_EMPTY)) !=
446 SCALER_DISPSTATX_EMPTY);
447
448 out:
449 drm_dev_exit(idx);
450 }
451
452 int vc4_hvs_atomic_check(struct drm_crtc *crtc, struct drm_atomic_state *state)
453 {
454 struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
455 struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc_state);
456 struct drm_device *dev = crtc->dev;
457 struct vc4_dev *vc4 = to_vc4_dev(dev);
458 struct drm_plane *plane;
459 unsigned long flags;
460 const struct drm_plane_state *plane_state;
461 u32 dlist_count = 0;
462 int ret;
463
464 /* The pixelvalve can only feed one encoder (and encoders are
465 * 1:1 with connectors.)
466 */
467 if (hweight32(crtc_state->connector_mask) > 1)
468 return -EINVAL;
469
470 drm_atomic_crtc_state_for_each_plane_state(plane, plane_state, crtc_state) {
471 u32 plane_dlist_count = vc4_plane_dlist_size(plane_state);
472
473 drm_dbg_driver(dev, "[CRTC:%d:%s] Found [PLANE:%d:%s] with DLIST size: %u\n",
474 crtc->base.id, crtc->name,
475 plane->base.id, plane->name,
476 plane_dlist_count);
477
478 dlist_count += plane_dlist_count;
479 }
480
481 dlist_count++; /* Account for SCALER_CTL0_END. */
482
483 drm_dbg_driver(dev, "[CRTC:%d:%s] Allocating DLIST block with size: %u\n",
484 crtc->base.id, crtc->name, dlist_count);
485 spin_lock_irqsave(&vc4->hvs->mm_lock, flags);
486 ret = drm_mm_insert_node(&vc4->hvs->dlist_mm, &vc4_state->mm,
487 dlist_count);
488 spin_unlock_irqrestore(&vc4->hvs->mm_lock, flags);
489 if (ret) {
490 drm_err(dev, "Failed to allocate DLIST entry: %d\n", ret);
491 return ret;
492 }
493
494 return 0;
495 }
496
497 static void vc4_hvs_install_dlist(struct drm_crtc *crtc)
498 {
499 struct drm_device *dev = crtc->dev;
500 struct vc4_dev *vc4 = to_vc4_dev(dev);
501 struct vc4_hvs *hvs = vc4->hvs;
502 struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
503 int idx;
504
505 if (!drm_dev_enter(dev, &idx))
506 return;
507
508 HVS_WRITE(SCALER_DISPLISTX(vc4_state->assigned_channel),
509 vc4_state->mm.start);
510
511 drm_dev_exit(idx);
512 }
513
514 static void vc4_hvs_update_dlist(struct drm_crtc *crtc)
515 {
516 struct drm_device *dev = crtc->dev;
517 struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
518 struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
519 unsigned long flags;
520
521 if (crtc->state->event) {
522 crtc->state->event->pipe = drm_crtc_index(crtc);
523
524 WARN_ON(drm_crtc_vblank_get(crtc) != 0);
525
526 spin_lock_irqsave(&dev->event_lock, flags);
527
528 if (!vc4_crtc->feeds_txp || vc4_state->txp_armed) {
529 vc4_crtc->event = crtc->state->event;
530 crtc->state->event = NULL;
531 }
532
533 spin_unlock_irqrestore(&dev->event_lock, flags);
534 }
535
536 spin_lock_irqsave(&vc4_crtc->irq_lock, flags);
537 vc4_crtc->current_dlist = vc4_state->mm.start;
538 spin_unlock_irqrestore(&vc4_crtc->irq_lock, flags);
539 }
540
541 void vc4_hvs_atomic_begin(struct drm_crtc *crtc,
542 struct drm_atomic_state *state)
543 {
544 struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
545 struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
546 unsigned long flags;
547
548 spin_lock_irqsave(&vc4_crtc->irq_lock, flags);
549 vc4_crtc->current_hvs_channel = vc4_state->assigned_channel;
550 spin_unlock_irqrestore(&vc4_crtc->irq_lock, flags);
551 }
552
553 void vc4_hvs_atomic_enable(struct drm_crtc *crtc,
554 struct drm_atomic_state *state)
555 {
556 struct drm_device *dev = crtc->dev;
557 struct vc4_dev *vc4 = to_vc4_dev(dev);
558 struct drm_display_mode *mode = &crtc->state->adjusted_mode;
559 struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
560 bool oneshot = vc4_crtc->feeds_txp;
561
562 vc4_hvs_install_dlist(crtc);
563 vc4_hvs_update_dlist(crtc);
564 vc4_hvs_init_channel(vc4->hvs, crtc, mode, oneshot);
565 }
566
567 void vc4_hvs_atomic_disable(struct drm_crtc *crtc,
568 struct drm_atomic_state *state)
569 {
570 struct drm_device *dev = crtc->dev;
571 struct vc4_dev *vc4 = to_vc4_dev(dev);
572 struct drm_crtc_state *old_state = drm_atomic_get_old_crtc_state(state, crtc);
573 struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(old_state);
574 unsigned int chan = vc4_state->assigned_channel;
575
576 vc4_hvs_stop_channel(vc4->hvs, chan);
577 }
578
579 void vc4_hvs_atomic_flush(struct drm_crtc *crtc,
580 struct drm_atomic_state *state)
581 {
582 struct drm_crtc_state *old_state = drm_atomic_get_old_crtc_state(state,
583 crtc);
584 struct drm_device *dev = crtc->dev;
585 struct vc4_dev *vc4 = to_vc4_dev(dev);
586 struct vc4_hvs *hvs = vc4->hvs;
587 struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);
588 struct vc4_crtc_state *vc4_state = to_vc4_crtc_state(crtc->state);
589 unsigned int channel = vc4_state->assigned_channel;
590 struct drm_plane *plane;
591 struct vc4_plane_state *vc4_plane_state;
592 bool debug_dump_regs = false;
593 bool enable_bg_fill = false;
594 u32 __iomem *dlist_start = vc4->hvs->dlist + vc4_state->mm.start;
595 u32 __iomem *dlist_next = dlist_start;
596 unsigned int zpos = 0;
597 bool found = false;
598 int idx;
599
600 if (!drm_dev_enter(dev, &idx)) {
601 vc4_crtc_send_vblank(crtc);
602 return;
603 }
604
605 if (vc4_state->assigned_channel == VC4_HVS_CHANNEL_DISABLED)
606 goto exit;
607
608 if (debug_dump_regs) {
609 DRM_INFO("CRTC %d HVS before:\n", drm_crtc_index(crtc));
610 vc4_hvs_dump_state(hvs);
611 }
612
613 /* Copy all the active planes' dlist contents to the hardware dlist. */
614 do {
615 found = false;
616
617 drm_atomic_crtc_for_each_plane(plane, crtc) {
618 if (plane->state->normalized_zpos != zpos)
619 continue;
620
621 /* Is this the first active plane? */
622 if (dlist_next == dlist_start) {
623 /* We need to enable background fill when a plane
624 * could be alpha blending from the background, i.e.
625 * where no other plane is underneath. It suffices to
626 * consider the first active plane here since we set
627 * needs_bg_fill such that either the first plane
628 * already needs it or all planes on top blend from
629 * the first or a lower plane.
630 */
631 vc4_plane_state = to_vc4_plane_state(plane->state);
632 enable_bg_fill = vc4_plane_state->needs_bg_fill;
633 }
634
635 dlist_next += vc4_plane_write_dlist(plane, dlist_next);
636
637 found = true;
638 }
639
640 zpos++;
641 } while (found);
642
643 writel(SCALER_CTL0_END, dlist_next);
644 dlist_next++;
645
646 WARN_ON_ONCE(dlist_next - dlist_start != vc4_state->mm.size);
647
648 if (enable_bg_fill)
649 /* This sets a black background color fill, as is the case
650 * with other DRM drivers.
651 */
652 HVS_WRITE(SCALER_DISPBKGNDX(channel),
653 HVS_READ(SCALER_DISPBKGNDX(channel)) |
654 SCALER_DISPBKGND_FILL);
655
656 /* Only update DISPLIST if the CRTC was already running and is not
657 * being disabled.
658 * vc4_crtc_enable() takes care of updating the dlist just after
659 * re-enabling VBLANK interrupts and before enabling the engine.
660 * If the CRTC is being disabled, there's no point in updating this
661 * information.
662 */
663 if (crtc->state->active && old_state->active) {
664 vc4_hvs_install_dlist(crtc);
665 vc4_hvs_update_dlist(crtc);
666 }
667
668 if (crtc->state->color_mgmt_changed) {
669 u32 dispbkgndx = HVS_READ(SCALER_DISPBKGNDX(channel));
670
671 if (crtc->state->gamma_lut) {
672 vc4_hvs_update_gamma_lut(hvs, vc4_crtc);
673 dispbkgndx |= SCALER_DISPBKGND_GAMMA;
674 } else {
675 /* Unsetting DISPBKGND_GAMMA skips the gamma lut step
676 * in hardware, which is the same as a linear lut that
677 * DRM expects us to use in absence of a user lut.
678 */
679 dispbkgndx &= ~SCALER_DISPBKGND_GAMMA;
680 }
681 HVS_WRITE(SCALER_DISPBKGNDX(channel), dispbkgndx);
682 }
683
684 if (debug_dump_regs) {
685 DRM_INFO("CRTC %d HVS after:\n", drm_crtc_index(crtc));
686 vc4_hvs_dump_state(hvs);
687 }
688
689 exit:
690 drm_dev_exit(idx);
691 }
692
693 void vc4_hvs_mask_underrun(struct vc4_hvs *hvs, int channel)
694 {
695 struct vc4_dev *vc4 = hvs->vc4;
696 struct drm_device *drm = &vc4->base;
697 u32 dispctrl;
698 int idx;
699
700 if (!drm_dev_enter(drm, &idx))
701 return;
702
703 dispctrl = HVS_READ(SCALER_DISPCTRL);
704 dispctrl &= ~((vc4->gen == VC4_GEN_5) ?
705 SCALER5_DISPCTRL_DSPEISLUR(channel) :
706 SCALER_DISPCTRL_DSPEISLUR(channel));
707
708 HVS_WRITE(SCALER_DISPCTRL, dispctrl);
709
710 drm_dev_exit(idx);
711 }
712
713 void vc4_hvs_unmask_underrun(struct vc4_hvs *hvs, int channel)
714 {
715 struct vc4_dev *vc4 = hvs->vc4;
716 struct drm_device *drm = &vc4->base;
717 u32 dispctrl;
718 int idx;
719
720 if (!drm_dev_enter(drm, &idx))
721 return;
722
723 dispctrl = HVS_READ(SCALER_DISPCTRL);
724 dispctrl |= ((vc4->gen == VC4_GEN_5) ?
725 SCALER5_DISPCTRL_DSPEISLUR(channel) :
726 SCALER_DISPCTRL_DSPEISLUR(channel));
727
728 HVS_WRITE(SCALER_DISPSTAT,
729 SCALER_DISPSTAT_EUFLOW(channel));
730 HVS_WRITE(SCALER_DISPCTRL, dispctrl);
731
732 drm_dev_exit(idx);
733 }
734
735 static void vc4_hvs_report_underrun(struct drm_device *dev)
736 {
737 struct vc4_dev *vc4 = to_vc4_dev(dev);
738
739 atomic_inc(&vc4->underrun);
740 DRM_DEV_ERROR(dev->dev, "HVS underrun\n");
741 }
742
743 static irqreturn_t vc4_hvs_irq_handler(int irq, void *data)
744 {
745 struct drm_device *dev = data;
746 struct vc4_dev *vc4 = to_vc4_dev(dev);
747 struct vc4_hvs *hvs = vc4->hvs;
748 irqreturn_t irqret = IRQ_NONE;
749 int channel;
750 u32 control;
751 u32 status;
752 u32 dspeislur;
753
754 /*
755 * NOTE: We don't need to protect the register access using
756 * drm_dev_enter() there because the interrupt handler lifetime
757 * is tied to the device itself, and not to the DRM device.
758 *
759 * So when the device will be gone, one of the first thing we
760 * will be doing will be to unregister the interrupt handler,
761 * and then unregister the DRM device. drm_dev_enter() would
762 * thus always succeed if we are here.
763 */
764
765 status = HVS_READ(SCALER_DISPSTAT);
766 control = HVS_READ(SCALER_DISPCTRL);
767
768 for (channel = 0; channel < SCALER_CHANNELS_COUNT; channel++) {
769 dspeislur = (vc4->gen == VC4_GEN_5) ?
770 SCALER5_DISPCTRL_DSPEISLUR(channel) :
771 SCALER_DISPCTRL_DSPEISLUR(channel);
772
773 /* Interrupt masking is not always honored, so check it here. */
774 if (status & SCALER_DISPSTAT_EUFLOW(channel) &&
775 control & dspeislur) {
776 vc4_hvs_mask_underrun(hvs, channel);
777 vc4_hvs_report_underrun(dev);
778
779 irqret = IRQ_HANDLED;
780 }
781 }
782
783 /* Clear every per-channel interrupt flag. */
784 HVS_WRITE(SCALER_DISPSTAT, SCALER_DISPSTAT_IRQMASK(0) |
785 SCALER_DISPSTAT_IRQMASK(1) |
786 SCALER_DISPSTAT_IRQMASK(2));
787
788 return irqret;
789 }
790
791 int vc4_hvs_debugfs_init(struct drm_minor *minor)
792 {
793 struct drm_device *drm = minor->dev;
794 struct vc4_dev *vc4 = to_vc4_dev(drm);
795 struct vc4_hvs *hvs = vc4->hvs;
796
797 if (!vc4->hvs)
798 return -ENODEV;
799
800 if (vc4->gen == VC4_GEN_4)
801 debugfs_create_bool("hvs_load_tracker", S_IRUGO | S_IWUSR,
802 minor->debugfs_root,
803 &vc4->load_tracker_enabled);
804
805 drm_debugfs_add_file(drm, "hvs_dlists", vc4_hvs_debugfs_dlist, NULL);
806
807 drm_debugfs_add_file(drm, "hvs_underrun", vc4_hvs_debugfs_underrun, NULL);
808
809 vc4_debugfs_add_regset32(drm, "hvs_regs", &hvs->regset);
810
811 return 0;
812 }
813
814 struct vc4_hvs *__vc4_hvs_alloc(struct vc4_dev *vc4,
815 void __iomem *regs,
816 struct platform_device *pdev)
817 {
818 struct drm_device *drm = &vc4->base;
819 struct vc4_hvs *hvs;
820
821 hvs = drmm_kzalloc(drm, sizeof(*hvs), GFP_KERNEL);
822 if (!hvs)
823 return ERR_PTR(-ENOMEM);
824
825 hvs->vc4 = vc4;
826 hvs->regs = regs;
827 hvs->pdev = pdev;
828
829 spin_lock_init(&hvs->mm_lock);
830
831 /* Set up the HVS display list memory manager. We never
832 * overwrite the setup from the bootloader (just 128b out of
833 * our 16K), since we don't want to scramble the screen when
834 * transitioning from the firmware's boot setup to runtime.
835 */
836 hvs->dlist_mem_size = (SCALER_DLIST_SIZE >> 2) - HVS_BOOTLOADER_DLIST_END;
837 drm_mm_init(&hvs->dlist_mm,
838 HVS_BOOTLOADER_DLIST_END,
839 hvs->dlist_mem_size);
840
841 /* Set up the HVS LBM memory manager. We could have some more
842 * complicated data structure that allowed reuse of LBM areas
843 * between planes when they don't overlap on the screen, but
844 * for now we just allocate globally.
845 */
846 if (vc4->gen == VC4_GEN_4)
847 /* 48k words of 2x12-bit pixels */
848 drm_mm_init(&hvs->lbm_mm, 0, 48 * 1024);
849 else
850 /* 60k words of 4x12-bit pixels */
851 drm_mm_init(&hvs->lbm_mm, 0, 60 * 1024);
852
853 vc4->hvs = hvs;
854
855 return hvs;
856 }
857
858 static int vc4_hvs_hw_init(struct vc4_hvs *hvs)
859 {
860 struct vc4_dev *vc4 = hvs->vc4;
861 u32 dispctrl, reg;
862
863 dispctrl = HVS_READ(SCALER_DISPCTRL);
864 dispctrl |= SCALER_DISPCTRL_ENABLE;
865 HVS_WRITE(SCALER_DISPCTRL, dispctrl);
866
867 reg = HVS_READ(SCALER_DISPECTRL);
868 reg &= ~SCALER_DISPECTRL_DSP2_MUX_MASK;
869 HVS_WRITE(SCALER_DISPECTRL,
870 reg | VC4_SET_FIELD(0, SCALER_DISPECTRL_DSP2_MUX));
871
872 reg = HVS_READ(SCALER_DISPCTRL);
873 reg &= ~SCALER_DISPCTRL_DSP3_MUX_MASK;
874 HVS_WRITE(SCALER_DISPCTRL,
875 reg | VC4_SET_FIELD(3, SCALER_DISPCTRL_DSP3_MUX));
876
877 reg = HVS_READ(SCALER_DISPEOLN);
878 reg &= ~SCALER_DISPEOLN_DSP4_MUX_MASK;
879 HVS_WRITE(SCALER_DISPEOLN,
880 reg | VC4_SET_FIELD(3, SCALER_DISPEOLN_DSP4_MUX));
881
882 reg = HVS_READ(SCALER_DISPDITHER);
883 reg &= ~SCALER_DISPDITHER_DSP5_MUX_MASK;
884 HVS_WRITE(SCALER_DISPDITHER,
885 reg | VC4_SET_FIELD(3, SCALER_DISPDITHER_DSP5_MUX));
886
887 dispctrl = HVS_READ(SCALER_DISPCTRL);
888 dispctrl |= SCALER_DISPCTRL_DISPEIRQ(0) |
889 SCALER_DISPCTRL_DISPEIRQ(1) |
890 SCALER_DISPCTRL_DISPEIRQ(2);
891
892 if (vc4->gen == VC4_GEN_4)
893 dispctrl &= ~(SCALER_DISPCTRL_DMAEIRQ |
894 SCALER_DISPCTRL_SLVWREIRQ |
895 SCALER_DISPCTRL_SLVRDEIRQ |
896 SCALER_DISPCTRL_DSPEIEOF(0) |
897 SCALER_DISPCTRL_DSPEIEOF(1) |
898 SCALER_DISPCTRL_DSPEIEOF(2) |
899 SCALER_DISPCTRL_DSPEIEOLN(0) |
900 SCALER_DISPCTRL_DSPEIEOLN(1) |
901 SCALER_DISPCTRL_DSPEIEOLN(2) |
902 SCALER_DISPCTRL_DSPEISLUR(0) |
903 SCALER_DISPCTRL_DSPEISLUR(1) |
904 SCALER_DISPCTRL_DSPEISLUR(2) |
905 SCALER_DISPCTRL_SCLEIRQ);
906 else
907 dispctrl &= ~(SCALER_DISPCTRL_DMAEIRQ |
908 SCALER5_DISPCTRL_SLVEIRQ |
909 SCALER5_DISPCTRL_DSPEIEOF(0) |
910 SCALER5_DISPCTRL_DSPEIEOF(1) |
911 SCALER5_DISPCTRL_DSPEIEOF(2) |
912 SCALER5_DISPCTRL_DSPEIEOLN(0) |
913 SCALER5_DISPCTRL_DSPEIEOLN(1) |
914 SCALER5_DISPCTRL_DSPEIEOLN(2) |
915 SCALER5_DISPCTRL_DSPEISLUR(0) |
916 SCALER5_DISPCTRL_DSPEISLUR(1) |
917 SCALER5_DISPCTRL_DSPEISLUR(2) |
918 SCALER_DISPCTRL_SCLEIRQ);
919
920
921 /* Set AXI panic mode.
922 * VC4 panics when < 2 lines in FIFO.
923 * VC5 panics when less than 1 line in the FIFO.
924 */
925 dispctrl &= ~(SCALER_DISPCTRL_PANIC0_MASK |
926 SCALER_DISPCTRL_PANIC1_MASK |
927 SCALER_DISPCTRL_PANIC2_MASK);
928 dispctrl |= VC4_SET_FIELD(2, SCALER_DISPCTRL_PANIC0);
929 dispctrl |= VC4_SET_FIELD(2, SCALER_DISPCTRL_PANIC1);
930 dispctrl |= VC4_SET_FIELD(2, SCALER_DISPCTRL_PANIC2);
931
932 /* Set AXI panic mode.
933 * VC4 panics when < 2 lines in FIFO.
934 * VC5 panics when less than 1 line in the FIFO.
935 */
936 dispctrl &= ~(SCALER_DISPCTRL_PANIC0_MASK |
937 SCALER_DISPCTRL_PANIC1_MASK |
938 SCALER_DISPCTRL_PANIC2_MASK);
939 dispctrl |= VC4_SET_FIELD(2, SCALER_DISPCTRL_PANIC0);
940 dispctrl |= VC4_SET_FIELD(2, SCALER_DISPCTRL_PANIC1);
941 dispctrl |= VC4_SET_FIELD(2, SCALER_DISPCTRL_PANIC2);
942
943 HVS_WRITE(SCALER_DISPCTRL, dispctrl);
944
945 return 0;
946 }
947
948 static int vc4_hvs_cob_init(struct vc4_hvs *hvs)
949 {
950 struct vc4_dev *vc4 = hvs->vc4;
951 u32 reg, top;
952
953 /*
954 * Recompute Composite Output Buffer (COB) allocations for the
955 * displays
956 */
957 switch (vc4->gen) {
958 case VC4_GEN_4:
959 /* The COB is 20736 pixels, or just over 10 lines at 2048 wide.
960 * The bottom 2048 pixels are full 32bpp RGBA (intended for the
961 * TXP composing RGBA to memory), whilst the remainder are only
962 * 24bpp RGB.
963 *
964 * Assign 3 lines to channels 1 & 2, and just over 4 lines to
965 * channel 0.
966 */
967 #define VC4_COB_SIZE 20736
968 #define VC4_COB_LINE_WIDTH 2048
969 #define VC4_COB_NUM_LINES 3
970 reg = 0;
971 top = VC4_COB_LINE_WIDTH * VC4_COB_NUM_LINES;
972 reg |= (top - 1) << 16;
973 HVS_WRITE(SCALER_DISPBASE2, reg);
974 reg = top;
975 top += VC4_COB_LINE_WIDTH * VC4_COB_NUM_LINES;
976 reg |= (top - 1) << 16;
977 HVS_WRITE(SCALER_DISPBASE1, reg);
978 reg = top;
979 top = VC4_COB_SIZE;
980 reg |= (top - 1) << 16;
981 HVS_WRITE(SCALER_DISPBASE0, reg);
982 break;
983
984 case VC4_GEN_5:
985 /* The COB is 44416 pixels, or 10.8 lines at 4096 wide.
986 * The bottom 4096 pixels are full RGBA (intended for the TXP
987 * composing RGBA to memory), whilst the remainder are only
988 * RGB. Addressing is always pixel wide.
989 *
990 * Assign 3 lines of 4096 to channels 1 & 2, and just over 4
991 * lines. to channel 0.
992 */
993 #define VC5_COB_SIZE 44416
994 #define VC5_COB_LINE_WIDTH 4096
995 #define VC5_COB_NUM_LINES 3
996 reg = 0;
997 top = VC5_COB_LINE_WIDTH * VC5_COB_NUM_LINES;
998 reg |= top << 16;
999 HVS_WRITE(SCALER_DISPBASE2, reg);
1000 top += 16;
1001 reg = top;
1002 top += VC5_COB_LINE_WIDTH * VC5_COB_NUM_LINES;
1003 reg |= top << 16;
1004 HVS_WRITE(SCALER_DISPBASE1, reg);
1005 top += 16;
1006 reg = top;
1007 top = VC5_COB_SIZE;
1008 reg |= top << 16;
1009 HVS_WRITE(SCALER_DISPBASE0, reg);
1010 break;
1011
1012 default:
1013 return -EINVAL;
1014 }
1015
1016 return 0;
1017 }
1018
1019 static int vc4_hvs_bind(struct device *dev, struct device *master, void *data)
1020 {
1021 struct platform_device *pdev = to_platform_device(dev);
1022 struct drm_device *drm = dev_get_drvdata(master);
1023 struct vc4_dev *vc4 = to_vc4_dev(drm);
1024 struct vc4_hvs *hvs = NULL;
1025 void __iomem *regs;
1026 int ret;
1027
1028 regs = vc4_ioremap_regs(pdev, 0);
1029 if (IS_ERR(regs))
1030 return PTR_ERR(regs);
1031
1032 hvs = __vc4_hvs_alloc(vc4, regs, pdev);
1033 if (IS_ERR(hvs))
1034 return PTR_ERR(hvs);
1035
1036 hvs->regset.base = hvs->regs;
1037 hvs->regset.regs = vc4_hvs_regs;
1038 hvs->regset.nregs = ARRAY_SIZE(vc4_hvs_regs);
1039
1040 if (vc4->gen == VC4_GEN_5) {
1041 struct rpi_firmware *firmware;
1042 struct device_node *node;
1043 unsigned int max_rate;
1044
1045 node = rpi_firmware_find_node();
1046 if (!node)
1047 return -EINVAL;
1048
1049 firmware = rpi_firmware_get(node);
1050 of_node_put(node);
1051 if (!firmware)
1052 return -EPROBE_DEFER;
1053
1054 hvs->core_clk = devm_clk_get(&pdev->dev, NULL);
1055 if (IS_ERR(hvs->core_clk)) {
1056 dev_err(&pdev->dev, "Couldn't get core clock\n");
1057 return PTR_ERR(hvs->core_clk);
1058 }
1059
1060 max_rate = rpi_firmware_clk_get_max_rate(firmware,
1061 RPI_FIRMWARE_CORE_CLK_ID);
1062 rpi_firmware_put(firmware);
1063 if (max_rate >= 550000000)
1064 hvs->vc5_hdmi_enable_hdmi_20 = true;
1065
1066 if (max_rate >= 600000000)
1067 hvs->vc5_hdmi_enable_4096by2160 = true;
1068
1069 hvs->max_core_rate = max_rate;
1070
1071 ret = clk_prepare_enable(hvs->core_clk);
1072 if (ret) {
1073 dev_err(&pdev->dev, "Couldn't enable the core clock\n");
1074 return ret;
1075 }
1076 }
1077
1078 if (vc4->gen == VC4_GEN_4)
1079 hvs->dlist = hvs->regs + SCALER_DLIST_START;
1080 else
1081 hvs->dlist = hvs->regs + SCALER5_DLIST_START;
1082
1083 ret = vc4_hvs_hw_init(hvs);
1084 if (ret)
1085 return ret;
1086
1087 /* Upload filter kernels. We only have the one for now, so we
1088 * keep it around for the lifetime of the driver.
1089 */
1090 ret = vc4_hvs_upload_linear_kernel(hvs,
1091 &hvs->mitchell_netravali_filter,
1092 mitchell_netravali_1_3_1_3_kernel);
1093 if (ret)
1094 return ret;
1095
1096 ret = vc4_hvs_cob_init(hvs);
1097 if (ret)
1098 return ret;
1099
1100 ret = devm_request_irq(dev, platform_get_irq(pdev, 0),
1101 vc4_hvs_irq_handler, 0, "vc4 hvs", drm);
1102 if (ret)
1103 return ret;
1104
1105 return 0;
1106 }
1107
1108 static void vc4_hvs_unbind(struct device *dev, struct device *master,
1109 void *data)
1110 {
1111 struct drm_device *drm = dev_get_drvdata(master);
1112 struct vc4_dev *vc4 = to_vc4_dev(drm);
1113 struct vc4_hvs *hvs = vc4->hvs;
1114 struct drm_mm_node *node, *next;
1115
1116 if (drm_mm_node_allocated(&vc4->hvs->mitchell_netravali_filter))
1117 drm_mm_remove_node(&vc4->hvs->mitchell_netravali_filter);
1118
1119 drm_mm_for_each_node_safe(node, next, &vc4->hvs->dlist_mm)
1120 drm_mm_remove_node(node);
1121
1122 drm_mm_takedown(&vc4->hvs->dlist_mm);
1123
1124 drm_mm_for_each_node_safe(node, next, &vc4->hvs->lbm_mm)
1125 drm_mm_remove_node(node);
1126 drm_mm_takedown(&vc4->hvs->lbm_mm);
1127
1128 clk_disable_unprepare(hvs->core_clk);
1129
1130 vc4->hvs = NULL;
1131 }
1132
1133 static const struct component_ops vc4_hvs_ops = {
1134 .bind = vc4_hvs_bind,
1135 .unbind = vc4_hvs_unbind,
1136 };
1137
1138 static int vc4_hvs_dev_probe(struct platform_device *pdev)
1139 {
1140 return component_add(&pdev->dev, &vc4_hvs_ops);
1141 }
1142
1143 static void vc4_hvs_dev_remove(struct platform_device *pdev)
1144 {
1145 component_del(&pdev->dev, &vc4_hvs_ops);
1146 }
1147
1148 static const struct of_device_id vc4_hvs_dt_match[] = {
1149 { .compatible = "brcm,bcm2711-hvs" },
1150 { .compatible = "brcm,bcm2835-hvs" },
1151 {}
1152 };
1153
1154 struct platform_driver vc4_hvs_driver = {
1155 .probe = vc4_hvs_dev_probe,
1156 .remove = vc4_hvs_dev_remove,
1157 .driver = {
1158 .name = "vc4_hvs",
1159 .of_match_table = vc4_hvs_dt_match,
1160 },
1161 };
Linux Kernel