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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2015 Free Electrons
4 * Copyright (C) 2015 NextThing Co
5 *
6 * Maxime Ripard <maxime.ripard@free-electrons.com>
7 */
8
9#include <linux/component.h>
10#include <linux/list.h>
11#include <linux/module.h>
12#include <linux/of_device.h>
13#include <linux/of_graph.h>
14#include <linux/dma-mapping.h>
15#include <linux/platform_device.h>
16#include <linux/reset.h>
17
18#include <drm/drm_atomic.h>
19#include <drm/drm_atomic_helper.h>
20#include <drm/drm_blend.h>
21#include <drm/drm_crtc.h>
22#include <drm/drm_fb_dma_helper.h>
23#include <drm/drm_fourcc.h>
24#include <drm/drm_framebuffer.h>
25#include <drm/drm_gem_dma_helper.h>
26#include <drm/drm_probe_helper.h>
27
28#include "sun4i_backend.h"
29#include "sun4i_drv.h"
30#include "sun4i_frontend.h"
31#include "sun4i_layer.h"
32#include "sunxi_engine.h"
33
34struct sun4i_backend_quirks {
35 /* backend <-> TCON muxing selection done in backend */
36 bool needs_output_muxing;
37
38 /* alpha at the lowest z position is not always supported */
39 bool supports_lowest_plane_alpha;
40};
41
42static const u32 sunxi_rgb2yuv_coef[12] = {
43 0x00000107, 0x00000204, 0x00000064, 0x00000108,
44 0x00003f69, 0x00003ed6, 0x000001c1, 0x00000808,
45 0x000001c1, 0x00003e88, 0x00003fb8, 0x00000808
46};
47
48static void sun4i_backend_apply_color_correction(struct sunxi_engine *engine)
49{
50 int i;
51
52 DRM_DEBUG_DRIVER("Applying RGB to YUV color correction\n");
53
54 /* Set color correction */
55 regmap_write(engine->regs, SUN4I_BACKEND_OCCTL_REG,
56 SUN4I_BACKEND_OCCTL_ENABLE);
57
58 for (i = 0; i < 12; i++)
59 regmap_write(engine->regs, SUN4I_BACKEND_OCRCOEF_REG(i),
60 sunxi_rgb2yuv_coef[i]);
61}
62
63static void sun4i_backend_disable_color_correction(struct sunxi_engine *engine)
64{
65 DRM_DEBUG_DRIVER("Disabling color correction\n");
66
67 /* Disable color correction */
68 regmap_update_bits(engine->regs, SUN4I_BACKEND_OCCTL_REG,
69 SUN4I_BACKEND_OCCTL_ENABLE, 0);
70}
71
72static void sun4i_backend_commit(struct sunxi_engine *engine,
73 struct drm_crtc *crtc,
74 struct drm_atomic_state *state)
75{
76 DRM_DEBUG_DRIVER("Committing changes\n");
77
78 regmap_write(engine->regs, SUN4I_BACKEND_REGBUFFCTL_REG,
79 SUN4I_BACKEND_REGBUFFCTL_AUTOLOAD_DIS |
80 SUN4I_BACKEND_REGBUFFCTL_LOADCTL);
81}
82
83void sun4i_backend_layer_enable(struct sun4i_backend *backend,
84 int layer, bool enable)
85{
86 u32 val;
87
88 DRM_DEBUG_DRIVER("%sabling layer %d\n", enable ? "En" : "Dis",
89 layer);
90
91 if (enable)
92 val = SUN4I_BACKEND_MODCTL_LAY_EN(layer);
93 else
94 val = 0;
95
96 regmap_update_bits(backend->engine.regs, SUN4I_BACKEND_MODCTL_REG,
97 SUN4I_BACKEND_MODCTL_LAY_EN(layer), val);
98}
99
100static int sun4i_backend_drm_format_to_layer(u32 format, u32 *mode)
101{
102 switch (format) {
103 case DRM_FORMAT_ARGB8888:
104 *mode = SUN4I_BACKEND_LAY_FBFMT_ARGB8888;
105 break;
106
107 case DRM_FORMAT_ARGB4444:
108 *mode = SUN4I_BACKEND_LAY_FBFMT_ARGB4444;
109 break;
110
111 case DRM_FORMAT_ARGB1555:
112 *mode = SUN4I_BACKEND_LAY_FBFMT_ARGB1555;
113 break;
114
115 case DRM_FORMAT_RGBA5551:
116 *mode = SUN4I_BACKEND_LAY_FBFMT_RGBA5551;
117 break;
118
119 case DRM_FORMAT_RGBA4444:
120 *mode = SUN4I_BACKEND_LAY_FBFMT_RGBA4444;
121 break;
122
123 case DRM_FORMAT_XRGB8888:
124 *mode = SUN4I_BACKEND_LAY_FBFMT_XRGB8888;
125 break;
126
127 case DRM_FORMAT_RGB888:
128 *mode = SUN4I_BACKEND_LAY_FBFMT_RGB888;
129 break;
130
131 case DRM_FORMAT_RGB565:
132 *mode = SUN4I_BACKEND_LAY_FBFMT_RGB565;
133 break;
134
135 default:
136 return -EINVAL;
137 }
138
139 return 0;
140}
141
142static const uint32_t sun4i_backend_formats[] = {
143 DRM_FORMAT_ARGB1555,
144 DRM_FORMAT_ARGB4444,
145 DRM_FORMAT_ARGB8888,
146 DRM_FORMAT_RGB565,
147 DRM_FORMAT_RGB888,
148 DRM_FORMAT_RGBA4444,
149 DRM_FORMAT_RGBA5551,
150 DRM_FORMAT_UYVY,
151 DRM_FORMAT_VYUY,
152 DRM_FORMAT_XRGB8888,
153 DRM_FORMAT_YUYV,
154 DRM_FORMAT_YVYU,
155};
156
157bool sun4i_backend_format_is_supported(uint32_t fmt, uint64_t modifier)
158{
159 unsigned int i;
160
161 if (modifier != DRM_FORMAT_MOD_LINEAR)
162 return false;
163
164 for (i = 0; i < ARRAY_SIZE(sun4i_backend_formats); i++)
165 if (sun4i_backend_formats[i] == fmt)
166 return true;
167
168 return false;
169}
170
171int sun4i_backend_update_layer_coord(struct sun4i_backend *backend,
172 int layer, struct drm_plane *plane)
173{
174 struct drm_plane_state *state = plane->state;
175
176 DRM_DEBUG_DRIVER("Updating layer %d\n", layer);
177
178 /* Set height and width */
179 DRM_DEBUG_DRIVER("Layer size W: %u H: %u\n",
180 state->crtc_w, state->crtc_h);
181 regmap_write(backend->engine.regs, SUN4I_BACKEND_LAYSIZE_REG(layer),
182 SUN4I_BACKEND_LAYSIZE(state->crtc_w,
183 state->crtc_h));
184
185 /* Set base coordinates */
186 DRM_DEBUG_DRIVER("Layer coordinates X: %d Y: %d\n",
187 state->crtc_x, state->crtc_y);
188 regmap_write(backend->engine.regs, SUN4I_BACKEND_LAYCOOR_REG(layer),
189 SUN4I_BACKEND_LAYCOOR(state->crtc_x,
190 state->crtc_y));
191
192 return 0;
193}
194
195static int sun4i_backend_update_yuv_format(struct sun4i_backend *backend,
196 int layer, struct drm_plane *plane)
197{
198 struct drm_plane_state *state = plane->state;
199 struct drm_framebuffer *fb = state->fb;
200 const struct drm_format_info *format = fb->format;
201 const uint32_t fmt = format->format;
202 u32 val = SUN4I_BACKEND_IYUVCTL_EN;
203 int i;
204
205 for (i = 0; i < ARRAY_SIZE(sunxi_bt601_yuv2rgb_coef); i++)
206 regmap_write(backend->engine.regs,
207 SUN4I_BACKEND_YGCOEF_REG(i),
208 sunxi_bt601_yuv2rgb_coef[i]);
209
210 /*
211 * We should do that only for a single plane, but the
212 * framebuffer's atomic_check has our back on this.
213 */
214 regmap_update_bits(backend->engine.regs, SUN4I_BACKEND_ATTCTL_REG0(layer),
215 SUN4I_BACKEND_ATTCTL_REG0_LAY_YUVEN,
216 SUN4I_BACKEND_ATTCTL_REG0_LAY_YUVEN);
217
218 /* TODO: Add support for the multi-planar YUV formats */
219 if (drm_format_info_is_yuv_packed(format) &&
220 drm_format_info_is_yuv_sampling_422(format))
221 val |= SUN4I_BACKEND_IYUVCTL_FBFMT_PACKED_YUV422;
222 else
223 DRM_DEBUG_DRIVER("Unsupported YUV format (0x%x)\n", fmt);
224
225 /*
226 * Allwinner seems to list the pixel sequence from right to left, while
227 * DRM lists it from left to right.
228 */
229 switch (fmt) {
230 case DRM_FORMAT_YUYV:
231 val |= SUN4I_BACKEND_IYUVCTL_FBPS_VYUY;
232 break;
233 case DRM_FORMAT_YVYU:
234 val |= SUN4I_BACKEND_IYUVCTL_FBPS_UYVY;
235 break;
236 case DRM_FORMAT_UYVY:
237 val |= SUN4I_BACKEND_IYUVCTL_FBPS_YVYU;
238 break;
239 case DRM_FORMAT_VYUY:
240 val |= SUN4I_BACKEND_IYUVCTL_FBPS_YUYV;
241 break;
242 default:
243 DRM_DEBUG_DRIVER("Unsupported YUV pixel sequence (0x%x)\n",
244 fmt);
245 }
246
247 regmap_write(backend->engine.regs, SUN4I_BACKEND_IYUVCTL_REG, val);
248
249 return 0;
250}
251
252int sun4i_backend_update_layer_formats(struct sun4i_backend *backend,
253 int layer, struct drm_plane *plane)
254{
255 struct drm_plane_state *state = plane->state;
256 struct drm_framebuffer *fb = state->fb;
257 u32 val;
258 int ret;
259
260 /* Clear the YUV mode */
261 regmap_update_bits(backend->engine.regs, SUN4I_BACKEND_ATTCTL_REG0(layer),
262 SUN4I_BACKEND_ATTCTL_REG0_LAY_YUVEN, 0);
263
264 val = SUN4I_BACKEND_ATTCTL_REG0_LAY_GLBALPHA(state->alpha >> 8);
265 if (state->alpha != DRM_BLEND_ALPHA_OPAQUE)
266 val |= SUN4I_BACKEND_ATTCTL_REG0_LAY_GLBALPHA_EN;
267 regmap_update_bits(backend->engine.regs,
268 SUN4I_BACKEND_ATTCTL_REG0(layer),
269 SUN4I_BACKEND_ATTCTL_REG0_LAY_GLBALPHA_MASK |
270 SUN4I_BACKEND_ATTCTL_REG0_LAY_GLBALPHA_EN,
271 val);
272
273 if (fb->format->is_yuv)
274 return sun4i_backend_update_yuv_format(backend, layer, plane);
275
276 ret = sun4i_backend_drm_format_to_layer(fb->format->format, &val);
277 if (ret) {
278 DRM_DEBUG_DRIVER("Invalid format\n");
279 return ret;
280 }
281
282 regmap_update_bits(backend->engine.regs,
283 SUN4I_BACKEND_ATTCTL_REG1(layer),
284 SUN4I_BACKEND_ATTCTL_REG1_LAY_FBFMT, val);
285
286 return 0;
287}
288
289int sun4i_backend_update_layer_frontend(struct sun4i_backend *backend,
290 int layer, uint32_t fmt)
291{
292 u32 val;
293 int ret;
294
295 ret = sun4i_backend_drm_format_to_layer(fmt, &val);
296 if (ret) {
297 DRM_DEBUG_DRIVER("Invalid format\n");
298 return ret;
299 }
300
301 regmap_update_bits(backend->engine.regs,
302 SUN4I_BACKEND_ATTCTL_REG0(layer),
303 SUN4I_BACKEND_ATTCTL_REG0_LAY_VDOEN,
304 SUN4I_BACKEND_ATTCTL_REG0_LAY_VDOEN);
305
306 regmap_update_bits(backend->engine.regs,
307 SUN4I_BACKEND_ATTCTL_REG1(layer),
308 SUN4I_BACKEND_ATTCTL_REG1_LAY_FBFMT, val);
309
310 return 0;
311}
312
313static int sun4i_backend_update_yuv_buffer(struct sun4i_backend *backend,
314 struct drm_framebuffer *fb,
315 dma_addr_t paddr)
316{
317 /* TODO: Add support for the multi-planar YUV formats */
318 DRM_DEBUG_DRIVER("Setting packed YUV buffer address to %pad\n", &paddr);
319 regmap_write(backend->engine.regs, SUN4I_BACKEND_IYUVADD_REG(0), paddr);
320
321 DRM_DEBUG_DRIVER("Layer line width: %d bits\n", fb->pitches[0] * 8);
322 regmap_write(backend->engine.regs, SUN4I_BACKEND_IYUVLINEWIDTH_REG(0),
323 fb->pitches[0] * 8);
324
325 return 0;
326}
327
328int sun4i_backend_update_layer_buffer(struct sun4i_backend *backend,
329 int layer, struct drm_plane *plane)
330{
331 struct drm_plane_state *state = plane->state;
332 struct drm_framebuffer *fb = state->fb;
333 u32 lo_paddr, hi_paddr;
334 dma_addr_t dma_addr;
335
336 /* Set the line width */
337 DRM_DEBUG_DRIVER("Layer line width: %d bits\n", fb->pitches[0] * 8);
338 regmap_write(backend->engine.regs,
339 SUN4I_BACKEND_LAYLINEWIDTH_REG(layer),
340 fb->pitches[0] * 8);
341
342 /* Get the start of the displayed memory */
343 dma_addr = drm_fb_dma_get_gem_addr(fb, state, 0);
344 DRM_DEBUG_DRIVER("Setting buffer address to %pad\n", &dma_addr);
345
346 if (fb->format->is_yuv)
347 return sun4i_backend_update_yuv_buffer(backend, fb, dma_addr);
348
349 /* Write the 32 lower bits of the address (in bits) */
350 lo_paddr = dma_addr << 3;
351 DRM_DEBUG_DRIVER("Setting address lower bits to 0x%x\n", lo_paddr);
352 regmap_write(backend->engine.regs,
353 SUN4I_BACKEND_LAYFB_L32ADD_REG(layer),
354 lo_paddr);
355
356 /* And the upper bits */
357 hi_paddr = dma_addr >> 29;
358 DRM_DEBUG_DRIVER("Setting address high bits to 0x%x\n", hi_paddr);
359 regmap_update_bits(backend->engine.regs, SUN4I_BACKEND_LAYFB_H4ADD_REG,
360 SUN4I_BACKEND_LAYFB_H4ADD_MSK(layer),
361 SUN4I_BACKEND_LAYFB_H4ADD(layer, hi_paddr));
362
363 return 0;
364}
365
366int sun4i_backend_update_layer_zpos(struct sun4i_backend *backend, int layer,
367 struct drm_plane *plane)
368{
369 struct drm_plane_state *state = plane->state;
370 struct sun4i_layer_state *p_state = state_to_sun4i_layer_state(state);
371 unsigned int priority = state->normalized_zpos;
372 unsigned int pipe = p_state->pipe;
373
374 DRM_DEBUG_DRIVER("Setting layer %d's priority to %d and pipe %d\n",
375 layer, priority, pipe);
376 regmap_update_bits(backend->engine.regs, SUN4I_BACKEND_ATTCTL_REG0(layer),
377 SUN4I_BACKEND_ATTCTL_REG0_LAY_PIPESEL_MASK |
378 SUN4I_BACKEND_ATTCTL_REG0_LAY_PRISEL_MASK,
379 SUN4I_BACKEND_ATTCTL_REG0_LAY_PIPESEL(p_state->pipe) |
380 SUN4I_BACKEND_ATTCTL_REG0_LAY_PRISEL(priority));
381
382 return 0;
383}
384
385void sun4i_backend_cleanup_layer(struct sun4i_backend *backend,
386 int layer)
387{
388 regmap_update_bits(backend->engine.regs,
389 SUN4I_BACKEND_ATTCTL_REG0(layer),
390 SUN4I_BACKEND_ATTCTL_REG0_LAY_VDOEN |
391 SUN4I_BACKEND_ATTCTL_REG0_LAY_YUVEN, 0);
392}
393
394static bool sun4i_backend_plane_uses_scaler(struct drm_plane_state *state)
395{
396 u16 src_h = state->src_h >> 16;
397 u16 src_w = state->src_w >> 16;
398
399 DRM_DEBUG_DRIVER("Input size %dx%d, output size %dx%d\n",
400 src_w, src_h, state->crtc_w, state->crtc_h);
401
402 if ((state->crtc_h != src_h) || (state->crtc_w != src_w))
403 return true;
404
405 return false;
406}
407
408static bool sun4i_backend_plane_uses_frontend(struct drm_plane_state *state)
409{
410 struct sun4i_layer *layer = plane_to_sun4i_layer(state->plane);
411 struct sun4i_backend *backend = layer->backend;
412 uint32_t format = state->fb->format->format;
413 uint64_t modifier = state->fb->modifier;
414
415 if (IS_ERR(backend->frontend))
416 return false;
417
418 if (!sun4i_frontend_format_is_supported(format, modifier))
419 return false;
420
421 if (!sun4i_backend_format_is_supported(format, modifier))
422 return true;
423
424 /*
425 * TODO: The backend alone allows 2x and 4x integer scaling, including
426 * support for an alpha component (which the frontend doesn't support).
427 * Use the backend directly instead of the frontend in this case, with
428 * another test to return false.
429 */
430
431 if (sun4i_backend_plane_uses_scaler(state))
432 return true;
433
434 /*
435 * Here the format is supported by both the frontend and the backend
436 * and no frontend scaling is required, so use the backend directly.
437 */
438 return false;
439}
440
441static bool sun4i_backend_plane_is_supported(struct drm_plane_state *state,
442 bool *uses_frontend)
443{
444 if (sun4i_backend_plane_uses_frontend(state)) {
445 *uses_frontend = true;
446 return true;
447 }
448
449 *uses_frontend = false;
450
451 /* Scaling is not supported without the frontend. */
452 if (sun4i_backend_plane_uses_scaler(state))
453 return false;
454
455 return true;
456}
457
458static void sun4i_backend_atomic_begin(struct sunxi_engine *engine,
459 struct drm_crtc_state *old_state)
460{
461 u32 val;
462
463 WARN_ON(regmap_read_poll_timeout(engine->regs,
464 SUN4I_BACKEND_REGBUFFCTL_REG,
465 val, !(val & SUN4I_BACKEND_REGBUFFCTL_LOADCTL),
466 100, 50000));
467}
468
469static int sun4i_backend_atomic_check(struct sunxi_engine *engine,
470 struct drm_crtc_state *crtc_state)
471{
472 struct drm_plane_state *plane_states[SUN4I_BACKEND_NUM_LAYERS] = { 0 };
473 struct sun4i_backend *backend = engine_to_sun4i_backend(engine);
474 struct drm_atomic_state *state = crtc_state->state;
475 struct drm_device *drm = state->dev;
476 struct drm_plane *plane;
477 unsigned int num_planes = 0;
478 unsigned int num_alpha_planes = 0;
479 unsigned int num_frontend_planes = 0;
480 unsigned int num_alpha_planes_max = 1;
481 unsigned int num_yuv_planes = 0;
482 unsigned int current_pipe = 0;
483 unsigned int i;
484
485 DRM_DEBUG_DRIVER("Starting checking our planes\n");
486
487 if (!crtc_state->planes_changed)
488 return 0;
489
490 drm_for_each_plane_mask(plane, drm, crtc_state->plane_mask) {
491 struct drm_plane_state *plane_state =
492 drm_atomic_get_plane_state(state, plane);
493 struct sun4i_layer_state *layer_state =
494 state_to_sun4i_layer_state(plane_state);
495 struct drm_framebuffer *fb = plane_state->fb;
496
497 if (!sun4i_backend_plane_is_supported(plane_state,
498 &layer_state->uses_frontend))
499 return -EINVAL;
500
501 if (layer_state->uses_frontend) {
502 DRM_DEBUG_DRIVER("Using the frontend for plane %d\n",
503 plane->index);
504 num_frontend_planes++;
505 } else {
506 if (fb->format->is_yuv) {
507 DRM_DEBUG_DRIVER("Plane FB format is YUV\n");
508 num_yuv_planes++;
509 }
510 }
511
512 DRM_DEBUG_DRIVER("Plane FB format is %p4cc\n",
513 &fb->format->format);
514 if (fb->format->has_alpha || (plane_state->alpha != DRM_BLEND_ALPHA_OPAQUE))
515 num_alpha_planes++;
516
517 DRM_DEBUG_DRIVER("Plane zpos is %d\n",
518 plane_state->normalized_zpos);
519
520 /* Sort our planes by Zpos */
521 plane_states[plane_state->normalized_zpos] = plane_state;
522
523 num_planes++;
524 }
525
526 /* All our planes were disabled, bail out */
527 if (!num_planes)
528 return 0;
529
530 /*
531 * The hardware is a bit unusual here.
532 *
533 * Even though it supports 4 layers, it does the composition
534 * in two separate steps.
535 *
536 * The first one is assigning a layer to one of its two
537 * pipes. If more that 1 layer is assigned to the same pipe,
538 * and if pixels overlaps, the pipe will take the pixel from
539 * the layer with the highest priority.
540 *
541 * The second step is the actual alpha blending, that takes
542 * the two pipes as input, and uses the potential alpha
543 * component to do the transparency between the two.
544 *
545 * This two-step scenario makes us unable to guarantee a
546 * robust alpha blending between the 4 layers in all
547 * situations, since this means that we need to have one layer
548 * with alpha at the lowest position of our two pipes.
549 *
550 * However, we cannot even do that on every platform, since
551 * the hardware has a bug where the lowest plane of the lowest
552 * pipe (pipe 0, priority 0), if it has any alpha, will
553 * discard the pixel data entirely and just display the pixels
554 * in the background color (black by default).
555 *
556 * This means that on the affected platforms, we effectively
557 * have only three valid configurations with alpha, all of
558 * them with the alpha being on pipe1 with the lowest
559 * position, which can be 1, 2 or 3 depending on the number of
560 * planes and their zpos.
561 */
562
563 /* For platforms that are not affected by the issue described above. */
564 if (backend->quirks->supports_lowest_plane_alpha)
565 num_alpha_planes_max++;
566
567 if (num_alpha_planes > num_alpha_planes_max) {
568 DRM_DEBUG_DRIVER("Too many planes with alpha, rejecting...\n");
569 return -EINVAL;
570 }
571
572 /* We can't have an alpha plane at the lowest position */
573 if (!backend->quirks->supports_lowest_plane_alpha &&
574 (plane_states[0]->alpha != DRM_BLEND_ALPHA_OPAQUE))
575 return -EINVAL;
576
577 for (i = 1; i < num_planes; i++) {
578 struct drm_plane_state *p_state = plane_states[i];
579 struct drm_framebuffer *fb = p_state->fb;
580 struct sun4i_layer_state *s_state = state_to_sun4i_layer_state(p_state);
581
582 /*
583 * The only alpha position is the lowest plane of the
584 * second pipe.
585 */
586 if (fb->format->has_alpha || (p_state->alpha != DRM_BLEND_ALPHA_OPAQUE))
587 current_pipe++;
588
589 s_state->pipe = current_pipe;
590 }
591
592 /* We can only have a single YUV plane at a time */
593 if (num_yuv_planes > SUN4I_BACKEND_NUM_YUV_PLANES) {
594 DRM_DEBUG_DRIVER("Too many planes with YUV, rejecting...\n");
595 return -EINVAL;
596 }
597
598 if (num_frontend_planes > SUN4I_BACKEND_NUM_FRONTEND_LAYERS) {
599 DRM_DEBUG_DRIVER("Too many planes going through the frontend, rejecting\n");
600 return -EINVAL;
601 }
602
603 DRM_DEBUG_DRIVER("State valid with %u planes, %u alpha, %u video, %u YUV\n",
604 num_planes, num_alpha_planes, num_frontend_planes,
605 num_yuv_planes);
606
607 return 0;
608}
609
610static void sun4i_backend_vblank_quirk(struct sunxi_engine *engine)
611{
612 struct sun4i_backend *backend = engine_to_sun4i_backend(engine);
613 struct sun4i_frontend *frontend = backend->frontend;
614
615 if (!frontend)
616 return;
617
618 /*
619 * In a teardown scenario with the frontend involved, we have
620 * to keep the frontend enabled until the next vblank, and
621 * only then disable it.
622 *
623 * This is due to the fact that the backend will not take into
624 * account the new configuration (with the plane that used to
625 * be fed by the frontend now disabled) until we write to the
626 * commit bit and the hardware fetches the new configuration
627 * during the next vblank.
628 *
629 * So we keep the frontend around in order to prevent any
630 * visual artifacts.
631 */
632 spin_lock(&backend->frontend_lock);
633 if (backend->frontend_teardown) {
634 sun4i_frontend_exit(frontend);
635 backend->frontend_teardown = false;
636 }
637 spin_unlock(&backend->frontend_lock);
638};
639
640static void sun4i_backend_mode_set(struct sunxi_engine *engine,
641 const struct drm_display_mode *mode)
642{
643 bool interlaced = !!(mode->flags & DRM_MODE_FLAG_INTERLACE);
644
645 DRM_DEBUG_DRIVER("Updating global size W: %u H: %u\n",
646 mode->hdisplay, mode->vdisplay);
647
648 regmap_write(engine->regs, SUN4I_BACKEND_DISSIZE_REG,
649 SUN4I_BACKEND_DISSIZE(mode->hdisplay, mode->vdisplay));
650
651 regmap_update_bits(engine->regs, SUN4I_BACKEND_MODCTL_REG,
652 SUN4I_BACKEND_MODCTL_ITLMOD_EN,
653 interlaced ? SUN4I_BACKEND_MODCTL_ITLMOD_EN : 0);
654
655 DRM_DEBUG_DRIVER("Switching display backend interlaced mode %s\n",
656 interlaced ? "on" : "off");
657}
658
659static int sun4i_backend_init_sat(struct device *dev) {
660 struct sun4i_backend *backend = dev_get_drvdata(dev);
661 int ret;
662
663 backend->sat_reset = devm_reset_control_get(dev, "sat");
664 if (IS_ERR(backend->sat_reset)) {
665 dev_err(dev, "Couldn't get the SAT reset line\n");
666 return PTR_ERR(backend->sat_reset);
667 }
668
669 ret = reset_control_deassert(backend->sat_reset);
670 if (ret) {
671 dev_err(dev, "Couldn't deassert the SAT reset line\n");
672 return ret;
673 }
674
675 backend->sat_clk = devm_clk_get(dev, "sat");
676 if (IS_ERR(backend->sat_clk)) {
677 dev_err(dev, "Couldn't get our SAT clock\n");
678 ret = PTR_ERR(backend->sat_clk);
679 goto err_assert_reset;
680 }
681
682 ret = clk_prepare_enable(backend->sat_clk);
683 if (ret) {
684 dev_err(dev, "Couldn't enable the SAT clock\n");
685 return ret;
686 }
687
688 return 0;
689
690err_assert_reset:
691 reset_control_assert(backend->sat_reset);
692 return ret;
693}
694
695static int sun4i_backend_free_sat(struct device *dev) {
696 struct sun4i_backend *backend = dev_get_drvdata(dev);
697
698 clk_disable_unprepare(backend->sat_clk);
699 reset_control_assert(backend->sat_reset);
700
701 return 0;
702}
703
704/*
705 * The display backend can take video output from the display frontend, or
706 * the display enhancement unit on the A80, as input for one it its layers.
707 * This relationship within the display pipeline is encoded in the device
708 * tree with of_graph, and we use it here to figure out which backend, if
709 * there are 2 or more, we are currently probing. The number would be in
710 * the "reg" property of the upstream output port endpoint.
711 */
712static int sun4i_backend_of_get_id(struct device_node *node)
713{
714 struct device_node *ep, *remote;
715 struct of_endpoint of_ep;
716
717 /* Input port is 0, and we want the first endpoint. */
718 ep = of_graph_get_endpoint_by_regs(node, 0, -1);
719 if (!ep)
720 return -EINVAL;
721
722 remote = of_graph_get_remote_endpoint(ep);
723 of_node_put(ep);
724 if (!remote)
725 return -EINVAL;
726
727 of_graph_parse_endpoint(remote, &of_ep);
728 of_node_put(remote);
729 return of_ep.id;
730}
731
732/* TODO: This needs to take multiple pipelines into account */
733static struct sun4i_frontend *sun4i_backend_find_frontend(struct sun4i_drv *drv,
734 struct device_node *node)
735{
736 struct device_node *port, *ep, *remote;
737 struct sun4i_frontend *frontend;
738
739 port = of_graph_get_port_by_id(node, 0);
740 if (!port)
741 return ERR_PTR(-EINVAL);
742
743 for_each_available_child_of_node(port, ep) {
744 remote = of_graph_get_remote_port_parent(ep);
745 if (!remote)
746 continue;
747 of_node_put(remote);
748
749 /* does this node match any registered engines? */
750 list_for_each_entry(frontend, &drv->frontend_list, list) {
751 if (remote == frontend->node) {
752 of_node_put(port);
753 of_node_put(ep);
754 return frontend;
755 }
756 }
757 }
758 of_node_put(port);
759 return ERR_PTR(-EINVAL);
760}
761
762static const struct sunxi_engine_ops sun4i_backend_engine_ops = {
763 .atomic_begin = sun4i_backend_atomic_begin,
764 .atomic_check = sun4i_backend_atomic_check,
765 .commit = sun4i_backend_commit,
766 .layers_init = sun4i_layers_init,
767 .apply_color_correction = sun4i_backend_apply_color_correction,
768 .disable_color_correction = sun4i_backend_disable_color_correction,
769 .vblank_quirk = sun4i_backend_vblank_quirk,
770 .mode_set = sun4i_backend_mode_set,
771};
772
773static const struct regmap_config sun4i_backend_regmap_config = {
774 .reg_bits = 32,
775 .val_bits = 32,
776 .reg_stride = 4,
777 .max_register = 0x5800,
778};
779
780static int sun4i_backend_bind(struct device *dev, struct device *master,
781 void *data)
782{
783 struct platform_device *pdev = to_platform_device(dev);
784 struct drm_device *drm = data;
785 struct sun4i_drv *drv = drm->dev_private;
786 struct sun4i_backend *backend;
787 const struct sun4i_backend_quirks *quirks;
788 void __iomem *regs;
789 int i, ret;
790
791 backend = devm_kzalloc(dev, sizeof(*backend), GFP_KERNEL);
792 if (!backend)
793 return -ENOMEM;
794 dev_set_drvdata(dev, backend);
795 spin_lock_init(&backend->frontend_lock);
796
797 if (of_property_present(dev->of_node, "interconnects")) {
798 /*
799 * This assume we have the same DMA constraints for all our the
800 * devices in our pipeline (all the backends, but also the
801 * frontends). This sounds bad, but it has always been the case
802 * for us, and DRM doesn't do per-device allocation either, so
803 * we would need to fix DRM first...
804 */
805 ret = of_dma_configure(drm->dev, dev->of_node, true);
806 if (ret)
807 return ret;
808 }
809
810 backend->engine.node = dev->of_node;
811 backend->engine.ops = &sun4i_backend_engine_ops;
812 backend->engine.id = sun4i_backend_of_get_id(dev->of_node);
813 if (backend->engine.id < 0)
814 return backend->engine.id;
815
816 backend->frontend = sun4i_backend_find_frontend(drv, dev->of_node);
817 if (IS_ERR(backend->frontend))
818 dev_warn(dev, "Couldn't find matching frontend, frontend features disabled\n");
819
820 regs = devm_platform_ioremap_resource(pdev, 0);
821 if (IS_ERR(regs))
822 return PTR_ERR(regs);
823
824 backend->reset = devm_reset_control_get(dev, NULL);
825 if (IS_ERR(backend->reset)) {
826 dev_err(dev, "Couldn't get our reset line\n");
827 return PTR_ERR(backend->reset);
828 }
829
830 ret = reset_control_deassert(backend->reset);
831 if (ret) {
832 dev_err(dev, "Couldn't deassert our reset line\n");
833 return ret;
834 }
835
836 backend->bus_clk = devm_clk_get(dev, "ahb");
837 if (IS_ERR(backend->bus_clk)) {
838 dev_err(dev, "Couldn't get the backend bus clock\n");
839 ret = PTR_ERR(backend->bus_clk);
840 goto err_assert_reset;
841 }
842 clk_prepare_enable(backend->bus_clk);
843
844 backend->mod_clk = devm_clk_get(dev, "mod");
845 if (IS_ERR(backend->mod_clk)) {
846 dev_err(dev, "Couldn't get the backend module clock\n");
847 ret = PTR_ERR(backend->mod_clk);
848 goto err_disable_bus_clk;
849 }
850
851 ret = clk_set_rate_exclusive(backend->mod_clk, 300000000);
852 if (ret) {
853 dev_err(dev, "Couldn't set the module clock frequency\n");
854 goto err_disable_bus_clk;
855 }
856
857 clk_prepare_enable(backend->mod_clk);
858
859 backend->ram_clk = devm_clk_get(dev, "ram");
860 if (IS_ERR(backend->ram_clk)) {
861 dev_err(dev, "Couldn't get the backend RAM clock\n");
862 ret = PTR_ERR(backend->ram_clk);
863 goto err_disable_mod_clk;
864 }
865 clk_prepare_enable(backend->ram_clk);
866
867 if (of_device_is_compatible(dev->of_node,
868 "allwinner,sun8i-a33-display-backend")) {
869 ret = sun4i_backend_init_sat(dev);
870 if (ret) {
871 dev_err(dev, "Couldn't init SAT resources\n");
872 goto err_disable_ram_clk;
873 }
874 }
875
876 backend->engine.regs = devm_regmap_init_mmio(dev, regs,
877 &sun4i_backend_regmap_config);
878 if (IS_ERR(backend->engine.regs)) {
879 dev_err(dev, "Couldn't create the backend regmap\n");
880 return PTR_ERR(backend->engine.regs);
881 }
882
883 list_add_tail(&backend->engine.list, &drv->engine_list);
884
885 /*
886 * Many of the backend's layer configuration registers have
887 * undefined default values. This poses a risk as we use
888 * regmap_update_bits in some places, and don't overwrite
889 * the whole register.
890 *
891 * Clear the registers here to have something predictable.
892 */
893 for (i = 0x800; i < 0x1000; i += 4)
894 regmap_write(backend->engine.regs, i, 0);
895
896 /* Disable registers autoloading */
897 regmap_write(backend->engine.regs, SUN4I_BACKEND_REGBUFFCTL_REG,
898 SUN4I_BACKEND_REGBUFFCTL_AUTOLOAD_DIS);
899
900 /* Enable the backend */
901 regmap_write(backend->engine.regs, SUN4I_BACKEND_MODCTL_REG,
902 SUN4I_BACKEND_MODCTL_DEBE_EN |
903 SUN4I_BACKEND_MODCTL_START_CTL);
904
905 /* Set output selection if needed */
906 quirks = of_device_get_match_data(dev);
907 if (quirks->needs_output_muxing) {
908 /*
909 * We assume there is no dynamic muxing of backends
910 * and TCONs, so we select the backend with same ID.
911 *
912 * While dynamic selection might be interesting, since
913 * the CRTC is tied to the TCON, while the layers are
914 * tied to the backends, this means, we will need to
915 * switch between groups of layers. There might not be
916 * a way to represent this constraint in DRM.
917 */
918 regmap_update_bits(backend->engine.regs,
919 SUN4I_BACKEND_MODCTL_REG,
920 SUN4I_BACKEND_MODCTL_OUT_SEL,
921 (backend->engine.id
922 ? SUN4I_BACKEND_MODCTL_OUT_LCD1
923 : SUN4I_BACKEND_MODCTL_OUT_LCD0));
924 }
925
926 backend->quirks = quirks;
927
928 return 0;
929
930err_disable_ram_clk:
931 clk_disable_unprepare(backend->ram_clk);
932err_disable_mod_clk:
933 clk_rate_exclusive_put(backend->mod_clk);
934 clk_disable_unprepare(backend->mod_clk);
935err_disable_bus_clk:
936 clk_disable_unprepare(backend->bus_clk);
937err_assert_reset:
938 reset_control_assert(backend->reset);
939 return ret;
940}
941
942static void sun4i_backend_unbind(struct device *dev, struct device *master,
943 void *data)
944{
945 struct sun4i_backend *backend = dev_get_drvdata(dev);
946
947 list_del(&backend->engine.list);
948
949 if (of_device_is_compatible(dev->of_node,
950 "allwinner,sun8i-a33-display-backend"))
951 sun4i_backend_free_sat(dev);
952
953 clk_disable_unprepare(backend->ram_clk);
954 clk_rate_exclusive_put(backend->mod_clk);
955 clk_disable_unprepare(backend->mod_clk);
956 clk_disable_unprepare(backend->bus_clk);
957 reset_control_assert(backend->reset);
958}
959
960static const struct component_ops sun4i_backend_ops = {
961 .bind = sun4i_backend_bind,
962 .unbind = sun4i_backend_unbind,
963};
964
965static int sun4i_backend_probe(struct platform_device *pdev)
966{
967 return component_add(&pdev->dev, &sun4i_backend_ops);
968}
969
970static void sun4i_backend_remove(struct platform_device *pdev)
971{
972 component_del(&pdev->dev, &sun4i_backend_ops);
973}
974
975static const struct sun4i_backend_quirks sun4i_backend_quirks = {
976 .needs_output_muxing = true,
977};
978
979static const struct sun4i_backend_quirks sun5i_backend_quirks = {
980};
981
982static const struct sun4i_backend_quirks sun6i_backend_quirks = {
983};
984
985static const struct sun4i_backend_quirks sun7i_backend_quirks = {
986 .needs_output_muxing = true,
987};
988
989static const struct sun4i_backend_quirks sun8i_a33_backend_quirks = {
990 .supports_lowest_plane_alpha = true,
991};
992
993static const struct sun4i_backend_quirks sun9i_backend_quirks = {
994};
995
996static const struct of_device_id sun4i_backend_of_table[] = {
997 {
998 .compatible = "allwinner,sun4i-a10-display-backend",
999 .data = &sun4i_backend_quirks,
1000 },
1001 {
1002 .compatible = "allwinner,sun5i-a13-display-backend",
1003 .data = &sun5i_backend_quirks,
1004 },
1005 {
1006 .compatible = "allwinner,sun6i-a31-display-backend",
1007 .data = &sun6i_backend_quirks,
1008 },
1009 {
1010 .compatible = "allwinner,sun7i-a20-display-backend",
1011 .data = &sun7i_backend_quirks,
1012 },
1013 {
1014 .compatible = "allwinner,sun8i-a23-display-backend",
1015 .data = &sun8i_a33_backend_quirks,
1016 },
1017 {
1018 .compatible = "allwinner,sun8i-a33-display-backend",
1019 .data = &sun8i_a33_backend_quirks,
1020 },
1021 {
1022 .compatible = "allwinner,sun9i-a80-display-backend",
1023 .data = &sun9i_backend_quirks,
1024 },
1025 { }
1026};
1027MODULE_DEVICE_TABLE(of, sun4i_backend_of_table);
1028
1029static struct platform_driver sun4i_backend_platform_driver = {
1030 .probe = sun4i_backend_probe,
1031 .remove = sun4i_backend_remove,
1032 .driver = {
1033 .name = "sun4i-backend",
1034 .of_match_table = sun4i_backend_of_table,
1035 },
1036};
1037module_platform_driver(sun4i_backend_platform_driver);
1038
1039MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
1040MODULE_DESCRIPTION("Allwinner A10 Display Backend Driver");
1041MODULE_LICENSE("GPL");