xref: /netbsd-src/sys/arch/arm/ti/ti_lcdc.c (revision f56b29a750628a7095c5912a389a6083a9f727f9)
1 /* $NetBSD: ti_lcdc.c,v 1.11 2022/04/21 21:22:25 andvar Exp $ */
2 
3 /*-
4  * Copyright (c) 2019 Jared D. McNeill <jmcneill@invisible.ca>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: ti_lcdc.c,v 1.11 2022/04/21 21:22:25 andvar Exp $");
31 
32 #include <sys/param.h>
33 #include <sys/bus.h>
34 #include <sys/device.h>
35 #include <sys/intr.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/conf.h>
39 
40 #include <uvm/uvm_extern.h>
41 #include <uvm/uvm_object.h>
42 #include <uvm/uvm_device.h>
43 
44 #include <drm/drm_crtc.h>
45 #include <drm/drm_crtc_helper.h>
46 #include <drm/drm_drv.h>
47 #include <drm/drm_fb_helper.h>
48 #include <drm/drm_fourcc.h>
49 #include <drm/drm_plane_helper.h>
50 
51 #include <dev/fdt/fdtvar.h>
52 #include <dev/fdt/fdt_port.h>
53 
54 #include <arm/ti/ti_prcm.h>
55 #include <arm/ti/ti_lcdc.h>
56 #include <arm/ti/ti_lcdcreg.h>
57 
58 static const struct device_compatible_entry compat_data[] = {
59 	{ .compat = "ti,am33xx-tilcdc" },
60 	DEVICE_COMPAT_EOL
61 };
62 
63 enum {
64 	TILCDC_PORT_OUTPUT = 0,
65 };
66 
67 static int	tilcdc_match(device_t, cfdata_t, void *);
68 static void	tilcdc_attach(device_t, device_t, void *);
69 
70 static int	tilcdc_load(struct drm_device *, unsigned long);
71 static void	tilcdc_unload(struct drm_device *);
72 
73 static void	tilcdc_drm_task_work(struct work *, void *);
74 
75 static struct drm_driver tilcdc_driver = {
76 	.driver_features = DRIVER_MODESET | DRIVER_GEM,
77 	.dev_priv_size = 0,
78 	.load = tilcdc_load,
79 	.unload = tilcdc_unload,
80 
81 	.gem_free_object = drm_gem_cma_free_object,
82 	.mmap_object = drm_gem_or_legacy_mmap_object,
83 	.gem_uvm_ops = &drm_gem_cma_uvm_ops,
84 
85 	.dumb_create = drm_gem_cma_dumb_create,
86 
87 	.name = DRIVER_NAME,
88 	.desc = DRIVER_DESC,
89 	.date = DRIVER_DATE,
90 	.major = DRIVER_MAJOR,
91 	.minor = DRIVER_MINOR,
92 	.patchlevel = DRIVER_PATCHLEVEL,
93 };
94 
95 CFATTACH_DECL_NEW(ti_lcdc, sizeof(struct tilcdc_softc),
96 	tilcdc_match, tilcdc_attach, NULL, NULL);
97 
98 static int
99 tilcdc_mode_do_set_base(struct drm_crtc *crtc, struct drm_framebuffer *fb,
100     int x, int y, int atomic)
101 {
102 	struct tilcdc_crtc *mixer_crtc = to_tilcdc_crtc(crtc);
103 	struct tilcdc_softc * const sc = mixer_crtc->sc;
104 	struct tilcdc_framebuffer *sfb = atomic?
105 	    to_tilcdc_framebuffer(fb) :
106 	    to_tilcdc_framebuffer(crtc->primary->fb);
107 
108 	const uint32_t paddr = (uint32_t)sfb->obj->dmamap->dm_segs[0].ds_addr;
109 	const u_int psize = sfb->obj->dmamap->dm_segs[0].ds_len;
110 
111 	/* Framebuffer start address */
112 	WR4(sc, LCD_LCDDMA_FB0_BASE, paddr);
113 	WR4(sc, LCD_LCDDMA_FB0_CEILING, paddr + psize - 1);
114 
115 	return 0;
116 }
117 
118 static void
119 tilcdc_destroy(struct drm_crtc *crtc)
120 {
121 	drm_crtc_cleanup(crtc);
122 }
123 
124 static const struct drm_crtc_funcs tilcdc_crtc_funcs = {
125 	.set_config = drm_crtc_helper_set_config,
126 	.destroy = tilcdc_destroy,
127 };
128 
129 static void
130 tilcdc_dpms(struct drm_crtc *crtc, int mode)
131 {
132 }
133 
134 static bool
135 tilcdc_mode_fixup(struct drm_crtc *crtc,
136     const struct drm_display_mode *mode, struct drm_display_mode *adjusted_mode)
137 {
138 #if 0
139 	adjusted_mode->hskew = mode->hsync_end - mode->hsync_start;
140 	adjusted_mode->flags |= DRM_MODE_FLAG_HSKEW;
141 
142 	adjusted_mode->flags &= ~(DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_PHSYNC);
143 	if (mode->flags & DRM_MODE_FLAG_NHSYNC)
144 		adjusted_mode->flags |= DRM_MODE_FLAG_PHSYNC;
145 	else
146 		adjusted_mode->flags |= DRM_MODE_FLAG_NHSYNC;
147 #endif
148 
149 	return true;
150 }
151 
152 static int
153 tilcdc_mode_set(struct drm_crtc *crtc, struct drm_display_mode *mode,
154     struct drm_display_mode *adjusted_mode, int x, int y,
155     struct drm_framebuffer *old_fb)
156 {
157 	struct tilcdc_crtc *mixer_crtc = to_tilcdc_crtc(crtc);
158 	struct tilcdc_softc * const sc = mixer_crtc->sc;
159 	int clk_div, div, diff, best_diff;
160 	uint32_t val;
161 
162 	const u_int hspw = adjusted_mode->crtc_hsync_end - adjusted_mode->crtc_hsync_start;
163 	const u_int hbp = adjusted_mode->crtc_htotal - adjusted_mode->crtc_hsync_end;
164 	const u_int hfp = adjusted_mode->crtc_hsync_start - adjusted_mode->crtc_hdisplay;
165 	const u_int vspw = adjusted_mode->crtc_vsync_end - adjusted_mode->crtc_vsync_start;
166 	const u_int vbp = adjusted_mode->crtc_vtotal - adjusted_mode->crtc_vsync_end;
167 	const u_int vfp = adjusted_mode->crtc_vsync_start - adjusted_mode->crtc_vdisplay;
168 
169 	const u_int rate = clk_get_rate(sc->sc_clk);
170 
171 	clk_div = 255;
172 	best_diff = -1;
173 	for (div = 2; div < 255; div++) {
174 		const int pixel_clock = (rate / div) / 1000;
175 		diff = abs(adjusted_mode->crtc_clock - pixel_clock);
176 		if (best_diff == -1 || diff < best_diff) {
177 			best_diff = diff;
178 			clk_div = div;
179 		}
180 	}
181 	if (clk_div == 255) {
182 		device_printf(sc->sc_dev, "couldn't configure pixel clock (%u)\n",
183 		    adjusted_mode->crtc_clock);
184 		return ERANGE;
185 	}
186 
187 	val = CTRL_RASTER_MODE |
188 	      (clk_div << CTRL_DIV_SHIFT);
189 	WR4(sc, LCD_CTRL, val);
190 
191 	val = RASTER_TIMING_0_HFP(hfp) |
192 	      RASTER_TIMING_0_HBP(hbp) |
193 	      RASTER_TIMING_0_HSW(hspw) |
194 	      RASTER_TIMING_0_PPL(adjusted_mode->hdisplay);
195 	WR4(sc, LCD_RASTER_TIMING_0, val);
196 
197 	val = RASTER_TIMING_1_VFP(vfp) |
198 	      RASTER_TIMING_1_VBP(vbp) |
199 	      RASTER_TIMING_1_VSW(vspw) |
200 	      RASTER_TIMING_1_LPP(adjusted_mode->vdisplay);
201 	WR4(sc, LCD_RASTER_TIMING_1, val);
202 
203 	val = RASTER_TIMING_2_HFP(hfp) |
204 	      RASTER_TIMING_2_HBP(hbp) |
205 	      RASTER_TIMING_2_HSW(hspw) |
206 	      RASTER_TIMING_2_LPP(adjusted_mode->vdisplay);
207 	/* XXX TDA HDMI TX */
208 	val |= RASTER_TIMING_2_IPC;
209 	val |= RASTER_TIMING_2_PHSVS;
210 	val |= RASTER_TIMING_2_PHSVS_RISE;
211 	val |= RASTER_TIMING_2_ACB(255);
212 	val |= RASTER_TIMING_2_ACBI(0);
213 	WR4(sc, LCD_RASTER_TIMING_2, val);
214 
215 	val = (4 << LCDDMA_CTRL_BURST_SIZE_SHIFT) |
216 	      (0 << LCDDMA_CTRL_TH_FIFO_RDY_SHIFT) |
217 	      LCDDMA_CTRL_FB0_ONLY;
218 	WR4(sc, LCD_LCDDMA_CTRL, val);
219 
220 	/* XXX TDA HDMI TX */
221 	val = RASTER_CTRL_LCDTFT |
222 	      RASTER_CTRL_TFT24 |
223 	      RASTER_CTRL_TFT24_UNPACKED |
224 	      RASTER_CTRL_REQDLY(0x80) |
225 	      RASTER_CTRL_PALMODE_DATA_ONLY;
226 	WR4(sc, LCD_RASTER_CTRL, val);
227 
228 	tilcdc_mode_do_set_base(crtc, old_fb, x, y, 0);
229 
230 	return 0;
231 }
232 
233 static int
234 tilcdc_mode_set_base(struct drm_crtc *crtc, int x, int y,
235     struct drm_framebuffer *old_fb)
236 {
237 	tilcdc_mode_do_set_base(crtc, old_fb, x, y, 0);
238 
239 	return 0;
240 }
241 
242 static int
243 tilcdc_mode_set_base_atomic(struct drm_crtc *crtc, struct drm_framebuffer *fb,
244     int x, int y, enum mode_set_atomic state)
245 {
246 	tilcdc_mode_do_set_base(crtc, fb, x, y, 1);
247 
248 	return 0;
249 }
250 
251 static void
252 tilcdc_disable(struct drm_crtc *crtc)
253 {
254 }
255 
256 static void
257 tilcdc_prepare(struct drm_crtc *crtc)
258 {
259 }
260 
261 static void
262 tilcdc_commit(struct drm_crtc *crtc)
263 {
264 	struct tilcdc_crtc *mixer_crtc = to_tilcdc_crtc(crtc);
265 	struct tilcdc_softc * const sc = mixer_crtc->sc;
266 	uint32_t val;
267 
268 	WR4(sc, LCD_CLKC_ENABLE, CLKC_ENABLE_DMA | CLKC_ENABLE_CORE);
269 	WR4(sc, LCD_CLKC_RESET, CLKC_RESET_MAIN);
270 	delay(100);
271 	WR4(sc, LCD_CLKC_RESET, 0);
272 
273 	val = RD4(sc, LCD_RASTER_CTRL);
274 	WR4(sc, LCD_RASTER_CTRL, val | RASTER_CTRL_LCDEN);
275 }
276 
277 static const struct drm_crtc_helper_funcs tilcdc_crtc_helper_funcs = {
278 	.dpms = tilcdc_dpms,
279 	.mode_fixup = tilcdc_mode_fixup,
280 	.mode_set = tilcdc_mode_set,
281 	.mode_set_base = tilcdc_mode_set_base,
282 	.mode_set_base_atomic = tilcdc_mode_set_base_atomic,
283 	.disable = tilcdc_disable,
284 	.prepare = tilcdc_prepare,
285 	.commit = tilcdc_commit,
286 };
287 
288 static void
289 tilcdc_encoder_destroy(struct drm_encoder *encoder)
290 {
291 }
292 
293 static const struct drm_encoder_funcs tilcdc_encoder_funcs = {
294 	.destroy = tilcdc_encoder_destroy,
295 };
296 
297 static void
298 tilcdc_encoder_dpms(struct drm_encoder *encoder, int mode)
299 {
300 }
301 
302 static bool
303 tilcdc_encoder_mode_fixup(struct drm_encoder *encoder,
304     const struct drm_display_mode *mode, struct drm_display_mode *adjusted_mode)
305 {
306 	return true;
307 }
308 
309 static void
310 tilcdc_encoder_mode_set(struct drm_encoder *encoder,
311     struct drm_display_mode *mode, struct drm_display_mode *adjusted_mode)
312 {
313 }
314 
315 static void
316 tilcdc_encoder_prepare(struct drm_encoder *encoder)
317 {
318 }
319 
320 static void
321 tilcdc_encoder_commit(struct drm_encoder *encoder)
322 {
323 }
324 
325 static const struct drm_encoder_helper_funcs tilcdc_encoder_helper_funcs = {
326 	.dpms = tilcdc_encoder_dpms,
327 	.mode_fixup = tilcdc_encoder_mode_fixup,
328 	.prepare = tilcdc_encoder_prepare,
329 	.commit = tilcdc_encoder_commit,
330 	.mode_set = tilcdc_encoder_mode_set,
331 };
332 
333 static int
334 tilcdc_ep_activate(device_t dev, struct fdt_endpoint *ep, bool activate)
335 {
336 	struct tilcdc_softc * const sc = device_private(dev);
337 	struct drm_device *ddev = sc->sc_ddev;
338 
339 	if (!activate)
340 		return EINVAL;
341 
342 	sc->sc_crtc.sc = sc;
343 
344 	WR4(sc, LCD_SYSCONFIG, SYSCONFIG_STANDBY_SMART | SYSCONFIG_IDLE_SMART);
345 
346 	drm_crtc_init(ddev, &sc->sc_crtc.base, &tilcdc_crtc_funcs);
347 	drm_crtc_helper_add(&sc->sc_crtc.base, &tilcdc_crtc_helper_funcs);
348 
349 	sc->sc_encoder.sc = sc;
350 	sc->sc_encoder.base.possible_crtcs = 1 << drm_crtc_index(&sc->sc_crtc.base);
351 
352 	drm_encoder_init(ddev, &sc->sc_encoder.base, &tilcdc_encoder_funcs,
353 	    DRM_MODE_ENCODER_TMDS, NULL);
354 	drm_encoder_helper_add(&sc->sc_encoder.base,
355 	    &tilcdc_encoder_helper_funcs);
356 
357 	return fdt_endpoint_activate(ep, activate);
358 }
359 
360 static void *
361 tilcdc_ep_get_data(device_t dev, struct fdt_endpoint *ep)
362 {
363 	struct tilcdc_softc * const sc = device_private(dev);
364 
365 	return &sc->sc_encoder.base;
366 }
367 
368 static int
369 tilcdc_match(device_t parent, cfdata_t cf, void *aux)
370 {
371 	struct fdt_attach_args * const faa = aux;
372 
373 	return of_compatible_match(faa->faa_phandle, compat_data);
374 }
375 
376 static void
377 tilcdc_attach(device_t parent, device_t self, void *aux)
378 {
379 	struct tilcdc_softc * const sc = device_private(self);
380 	struct fdt_attach_args * const faa = aux;
381 	const int phandle = faa->faa_phandle;
382 	struct drm_driver * const driver = &tilcdc_driver;
383 	prop_dictionary_t dict = device_properties(self);
384 	bool is_disabled;
385 	bus_addr_t addr;
386 	bus_size_t size;
387 	int error;
388 
389 	if (prop_dictionary_get_bool(dict, "disabled", &is_disabled) && is_disabled) {
390 		aprint_normal(": TI LCDC (disabled)\n");
391 		return;
392 	}
393 
394 	if (fdtbus_get_reg(phandle, 0, &addr, &size) != 0) {
395 		aprint_error(": couldn't get registers\n");
396 		return;
397 	}
398 
399 	sc->sc_dev = self;
400 	sc->sc_phandle = faa->faa_phandle;
401 	sc->sc_dmat = faa->faa_dmat;
402 	sc->sc_bst = faa->faa_bst;
403 	if (bus_space_map(sc->sc_bst, addr, size, 0, &sc->sc_bsh) != 0) {
404 		aprint_error(": couldn't map registers\n");
405 		return;
406 	}
407 	sc->sc_clk = ti_prcm_get_hwmod(phandle, 0);
408 	if (sc->sc_clk == NULL || clk_enable(sc->sc_clk) != 0) {
409 		aprint_error(": couldn't enable module\n");
410 		return;
411 	}
412 
413 	aprint_naive("\n");
414 	aprint_normal(": TI LCDC\n");
415 
416 	sc->sc_ports.dp_ep_activate = tilcdc_ep_activate;
417 	sc->sc_ports.dp_ep_get_data = tilcdc_ep_get_data;
418 	fdt_ports_register(&sc->sc_ports, self, phandle, EP_DRM_ENCODER);
419 
420 	sc->sc_task_thread = NULL;
421 	SIMPLEQ_INIT(&sc->sc_tasks);
422 	if (workqueue_create(&sc->sc_task_wq, "tilcdcdrm",
423 	    &tilcdc_drm_task_work, NULL, PRI_NONE, IPL_NONE, WQ_MPSAFE)) {
424 		aprint_error_dev(self, "unable to create workqueue\n");
425 		sc->sc_task_wq = NULL;
426 		return;
427 	}
428 
429 	sc->sc_ddev = drm_dev_alloc(driver, sc->sc_dev);
430 	if (IS_ERR(sc->sc_ddev)) {
431 		aprint_error_dev(self, "couldn't allocate DRM device\n");
432 		return;
433 	}
434 	sc->sc_ddev->dev_private = sc;
435 	sc->sc_ddev->bst = sc->sc_bst;
436 	sc->sc_ddev->bus_dmat = sc->sc_dmat;
437 	sc->sc_ddev->dmat = sc->sc_ddev->bus_dmat;
438 	sc->sc_ddev->dmat_subregion_p = false;
439 
440 	/*
441 	 * Cause any tasks issued synchronously during attach to be
442 	 * processed at the end of this function.
443 	 */
444 	sc->sc_task_thread = curlwp;
445 
446 	error = -drm_dev_register(sc->sc_ddev, 0);
447 	if (error) {
448 		drm_dev_put(sc->sc_ddev);
449 		sc->sc_ddev = NULL;
450 		aprint_error_dev(self, "couldn't register DRM device: %d\n",
451 		    error);
452 		goto out;
453 	}
454 	sc->sc_dev_registered = true;
455 
456 	aprint_normal_dev(self, "initialized %s %d.%d.%d %s on minor %d\n",
457 	    driver->name, driver->major, driver->minor, driver->patchlevel,
458 	    driver->date, sc->sc_ddev->primary->index);
459 
460 	/*
461 	 * Process asynchronous tasks queued synchronously during
462 	 * attach.  This will be for display detection to attach a
463 	 * framebuffer, so we have the opportunity for a console device
464 	 * to attach before autoconf has completed, in time for init(8)
465 	 * to find that console without panicking.
466 	 */
467 	while (!SIMPLEQ_EMPTY(&sc->sc_tasks)) {
468 		struct tilcdc_drm_task *const task =
469 		    SIMPLEQ_FIRST(&sc->sc_tasks);
470 
471 		SIMPLEQ_REMOVE_HEAD(&sc->sc_tasks, tdt_u.queue);
472 		(*task->tdt_fn)(task);
473 	}
474 
475 out:	/* Cause any subsequent tasks to be processed by the workqueue.  */
476 	atomic_store_relaxed(&sc->sc_task_thread, NULL);
477 }
478 
479 static int
480 tilcdc_fb_create_handle(struct drm_framebuffer *fb,
481     struct drm_file *file, unsigned int *handle)
482 {
483 	struct tilcdc_framebuffer *sfb = to_tilcdc_framebuffer(fb);
484 
485 	return drm_gem_handle_create(file, &sfb->obj->base, handle);
486 }
487 
488 static void
489 tilcdc_fb_destroy(struct drm_framebuffer *fb)
490 {
491 	struct tilcdc_framebuffer *sfb = to_tilcdc_framebuffer(fb);
492 
493 	drm_framebuffer_cleanup(fb);
494 	drm_gem_object_put_unlocked(&sfb->obj->base);
495 	kmem_free(sfb, sizeof(*sfb));
496 }
497 
498 static const struct drm_framebuffer_funcs tilcdc_framebuffer_funcs = {
499 	.create_handle = tilcdc_fb_create_handle,
500 	.destroy = tilcdc_fb_destroy,
501 };
502 
503 static struct drm_framebuffer *
504 tilcdc_fb_create(struct drm_device *ddev, struct drm_file *file,
505     const struct drm_mode_fb_cmd2 *cmd)
506 {
507 	struct tilcdc_framebuffer *fb;
508 	struct drm_gem_object *gem_obj;
509 	int error;
510 
511 	if (cmd->flags)
512 		return NULL;
513 
514 	gem_obj = drm_gem_object_lookup(file, cmd->handles[0]);
515 	if (gem_obj == NULL)
516 		return NULL;
517 
518 	fb = kmem_zalloc(sizeof(*fb), KM_SLEEP);
519 	drm_helper_mode_fill_fb_struct(ddev, &fb->base, cmd);
520 	fb->obj = to_drm_gem_cma_obj(gem_obj);
521 
522 	error = drm_framebuffer_init(ddev, &fb->base,
523 	    &tilcdc_framebuffer_funcs);
524 	if (error != 0)
525 		goto dealloc;
526 
527 	return &fb->base;
528 
529 dealloc:
530 	drm_framebuffer_cleanup(&fb->base);
531 	kmem_free(fb, sizeof(*fb));
532 	drm_gem_object_put_unlocked(gem_obj);
533 
534 	return NULL;
535 }
536 
537 static struct drm_mode_config_funcs tilcdc_mode_config_funcs = {
538 	.fb_create = tilcdc_fb_create,
539 };
540 
541 static int
542 tilcdc_fb_probe(struct drm_fb_helper *helper, struct drm_fb_helper_surface_size *sizes)
543 {
544 	struct tilcdc_softc * const sc = tilcdc_private(helper->dev);
545 	struct drm_device *ddev = helper->dev;
546 	struct tilcdc_framebuffer *sfb = to_tilcdc_framebuffer(helper->fb);
547 	struct drm_framebuffer *fb = helper->fb;
548 	struct tilcdcfb_attach_args tfa;
549 	const char *br_wiring;
550 	uint32_t pixel_format;
551 	int error;
552 
553 	const u_int width = sizes->surface_width;
554 	const u_int height = sizes->surface_height;
555 	const u_int pitch = width * (32 / 8);
556 
557 	br_wiring = fdtbus_get_string(sc->sc_phandle, "blue-and-red-wiring");
558 	if (br_wiring && strcmp(br_wiring, "straight") == 0) {
559 		pixel_format = DRM_FORMAT_XBGR8888;
560 	} else {
561 		pixel_format = DRM_FORMAT_XRGB8888;
562 	}
563 
564 	const size_t size = roundup(height * pitch, PAGE_SIZE);
565 
566 	sfb->obj = drm_gem_cma_create(ddev, size);
567 	if (sfb->obj == NULL) {
568 		DRM_ERROR("failed to allocate memory for framebuffer\n");
569 		return -ENOMEM;
570 	}
571 
572 	fb->pitches[0] = pitch;
573 	fb->offsets[0] = 0;
574 	fb->width = width;
575 	fb->height = height;
576 	fb->modifier = 0;
577 	fb->flags = 0;
578 	fb->format = drm_format_info(pixel_format);
579 	fb->dev = ddev;
580 
581 	error = drm_framebuffer_init(ddev, fb, &tilcdc_framebuffer_funcs);
582 	if (error != 0) {
583 		DRM_ERROR("failed to initialize framebuffer\n");
584 		return error;
585 	}
586 
587 	memset(&tfa, 0, sizeof(tfa));
588 	tfa.tfa_drm_dev = ddev;
589 	tfa.tfa_fb_helper = helper;
590 	tfa.tfa_fb_sizes = *sizes;
591 	tfa.tfa_fb_bst = sc->sc_bst;
592 	tfa.tfa_fb_dmat = sc->sc_dmat;
593 	tfa.tfa_fb_linebytes = helper->fb->pitches[0];
594 
595 	helper->fbdev = config_found(ddev->dev, &tfa, NULL,
596 	    CFARGS(.iattr = "tilcdcfbbus"));
597 	if (helper->fbdev == NULL) {
598 		DRM_ERROR("unable to attach framebuffer\n");
599 		return -ENXIO;
600 	}
601 
602 	return 0;
603 }
604 
605 static struct drm_fb_helper_funcs tilcdc_fb_helper_funcs = {
606 	.fb_probe = tilcdc_fb_probe,
607 };
608 
609 static int
610 tilcdc_load(struct drm_device *ddev, unsigned long flags)
611 {
612 	struct tilcdc_softc * const sc = tilcdc_private(ddev);
613 	struct tilcdc_fbdev *fbdev;
614 	struct fdt_endpoint *ep;
615 	int error;
616 
617 	drm_mode_config_init(ddev);
618 	ddev->mode_config.min_width = 0;
619 	ddev->mode_config.min_height = 0;
620 	ddev->mode_config.max_width = 2048;
621 	ddev->mode_config.max_height = 2048;
622 	ddev->mode_config.funcs = &tilcdc_mode_config_funcs;
623 
624 	ep = fdt_endpoint_get_from_index(&sc->sc_ports, TILCDC_PORT_OUTPUT, 0);
625 	if (ep == NULL) {
626 		aprint_error_dev(sc->sc_dev, "couldn't find endpoint\n");
627 		error = ENXIO;
628 		goto drmerr;
629 	}
630 	error = fdt_endpoint_activate_direct(ep, true);
631 	if (error != 0) {
632 		aprint_error_dev(sc->sc_dev, "couldn't activate endpoint: %d\n", error);
633 		error = ENXIO;
634 		goto drmerr;
635 	}
636 
637 	fbdev = kmem_zalloc(sizeof(*fbdev), KM_SLEEP);
638 
639 	drm_fb_helper_prepare(ddev, &fbdev->helper, &tilcdc_fb_helper_funcs);
640 
641 	error = drm_fb_helper_init(ddev, &fbdev->helper, 1);
642 	if (error)
643 		goto allocerr;
644 
645 	fbdev->helper.fb = kmem_zalloc(sizeof(struct tilcdc_framebuffer),
646 	    KM_SLEEP);
647 
648 	drm_fb_helper_single_add_all_connectors(&fbdev->helper);
649 
650 	drm_helper_disable_unused_functions(ddev);
651 
652 	drm_fb_helper_initial_config(&fbdev->helper, 32);
653 
654 	return 0;
655 
656 allocerr:
657 	kmem_free(fbdev, sizeof(*fbdev));
658 drmerr:
659 	drm_mode_config_cleanup(ddev);
660 
661 	return error;
662 }
663 
664 static void
665 tilcdc_unload(struct drm_device *ddev)
666 {
667 
668 	drm_mode_config_cleanup(ddev);
669 }
670 
671 static void
672 tilcdc_drm_task_work(struct work *work, void *cookie)
673 {
674 	struct tilcdc_drm_task *task = container_of(work,
675 	    struct tilcdc_drm_task, tdt_u.work);
676 
677 	(*task->tdt_fn)(task);
678 }
679 
680 void
681 tilcdc_task_init(struct tilcdc_drm_task *task,
682     void (*fn)(struct tilcdc_drm_task *))
683 {
684 
685 	task->tdt_fn = fn;
686 }
687 
688 void
689 tilcdc_task_schedule(device_t self, struct tilcdc_drm_task *task)
690 {
691 	struct tilcdc_softc *sc = device_private(self);
692 
693 	if (atomic_load_relaxed(&sc->sc_task_thread) == curlwp)
694 		SIMPLEQ_INSERT_TAIL(&sc->sc_tasks, task, tdt_u.queue);
695 	else
696 		workqueue_enqueue(sc->sc_task_wq, &task->tdt_u.work, NULL);
697 }
698