xref: /openbmc/linux/drivers/gpu/drm/mxsfb/mxsfb_kms.c (revision 8dce88fe)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2016 Marek Vasut <marex@denx.de>
4  *
5  * This code is based on drivers/video/fbdev/mxsfb.c :
6  * Copyright (C) 2010 Juergen Beisert, Pengutronix
7  * Copyright (C) 2008-2009 Freescale Semiconductor, Inc. All Rights Reserved.
8  * Copyright (C) 2008 Embedded Alley Solutions, Inc All Rights Reserved.
9  */
10 
11 #include <linux/clk.h>
12 #include <linux/io.h>
13 #include <linux/iopoll.h>
14 #include <linux/pm_runtime.h>
15 #include <linux/spinlock.h>
16 
17 #include <drm/drm_atomic.h>
18 #include <drm/drm_atomic_helper.h>
19 #include <drm/drm_bridge.h>
20 #include <drm/drm_crtc.h>
21 #include <drm/drm_encoder.h>
22 #include <drm/drm_fb_cma_helper.h>
23 #include <drm/drm_fourcc.h>
24 #include <drm/drm_gem_atomic_helper.h>
25 #include <drm/drm_gem_cma_helper.h>
26 #include <drm/drm_plane.h>
27 #include <drm/drm_plane_helper.h>
28 #include <drm/drm_vblank.h>
29 
30 #include "mxsfb_drv.h"
31 #include "mxsfb_regs.h"
32 
33 /* 1 second delay should be plenty of time for block reset */
34 #define RESET_TIMEOUT		1000000
35 
36 /* -----------------------------------------------------------------------------
37  * CRTC
38  */
39 
40 static u32 set_hsync_pulse_width(struct mxsfb_drm_private *mxsfb, u32 val)
41 {
42 	return (val & mxsfb->devdata->hs_wdth_mask) <<
43 		mxsfb->devdata->hs_wdth_shift;
44 }
45 
46 /*
47  * Setup the MXSFB registers for decoding the pixels out of the framebuffer and
48  * outputting them on the bus.
49  */
50 static void mxsfb_set_formats(struct mxsfb_drm_private *mxsfb,
51 			      const u32 bus_format)
52 {
53 	struct drm_device *drm = mxsfb->drm;
54 	const u32 format = mxsfb->crtc.primary->state->fb->format->format;
55 	u32 ctrl, ctrl1;
56 
57 	DRM_DEV_DEBUG_DRIVER(drm->dev, "Using bus_format: 0x%08X\n",
58 			     bus_format);
59 
60 	ctrl = CTRL_BYPASS_COUNT | CTRL_MASTER;
61 
62 	/* CTRL1 contains IRQ config and status bits, preserve those. */
63 	ctrl1 = readl(mxsfb->base + LCDC_CTRL1);
64 	ctrl1 &= CTRL1_CUR_FRAME_DONE_IRQ_EN | CTRL1_CUR_FRAME_DONE_IRQ;
65 
66 	switch (format) {
67 	case DRM_FORMAT_RGB565:
68 		dev_dbg(drm->dev, "Setting up RGB565 mode\n");
69 		ctrl |= CTRL_WORD_LENGTH_16;
70 		ctrl1 |= CTRL1_SET_BYTE_PACKAGING(0xf);
71 		break;
72 	case DRM_FORMAT_XRGB8888:
73 		dev_dbg(drm->dev, "Setting up XRGB8888 mode\n");
74 		ctrl |= CTRL_WORD_LENGTH_24;
75 		/* Do not use packed pixels = one pixel per word instead. */
76 		ctrl1 |= CTRL1_SET_BYTE_PACKAGING(0x7);
77 		break;
78 	}
79 
80 	switch (bus_format) {
81 	case MEDIA_BUS_FMT_RGB565_1X16:
82 		ctrl |= CTRL_BUS_WIDTH_16;
83 		break;
84 	case MEDIA_BUS_FMT_RGB666_1X18:
85 		ctrl |= CTRL_BUS_WIDTH_18;
86 		break;
87 	case MEDIA_BUS_FMT_RGB888_1X24:
88 		ctrl |= CTRL_BUS_WIDTH_24;
89 		break;
90 	default:
91 		dev_err(drm->dev, "Unknown media bus format 0x%x\n", bus_format);
92 		break;
93 	}
94 
95 	writel(ctrl1, mxsfb->base + LCDC_CTRL1);
96 	writel(ctrl, mxsfb->base + LCDC_CTRL);
97 }
98 
99 static void mxsfb_enable_controller(struct mxsfb_drm_private *mxsfb)
100 {
101 	u32 reg;
102 
103 	if (mxsfb->clk_disp_axi)
104 		clk_prepare_enable(mxsfb->clk_disp_axi);
105 	clk_prepare_enable(mxsfb->clk);
106 
107 	/* Increase number of outstanding requests on all supported IPs */
108 	if (mxsfb->devdata->has_ctrl2) {
109 		reg = readl(mxsfb->base + LCDC_V4_CTRL2);
110 		reg &= ~CTRL2_SET_OUTSTANDING_REQS_MASK;
111 		reg |= CTRL2_SET_OUTSTANDING_REQS_16;
112 		writel(reg, mxsfb->base + LCDC_V4_CTRL2);
113 	}
114 
115 	/* If it was disabled, re-enable the mode again */
116 	writel(CTRL_DOTCLK_MODE, mxsfb->base + LCDC_CTRL + REG_SET);
117 
118 	/* Enable the SYNC signals first, then the DMA engine */
119 	reg = readl(mxsfb->base + LCDC_VDCTRL4);
120 	reg |= VDCTRL4_SYNC_SIGNALS_ON;
121 	writel(reg, mxsfb->base + LCDC_VDCTRL4);
122 
123 	/*
124 	 * Enable recovery on underflow.
125 	 *
126 	 * There is some sort of corner case behavior of the controller,
127 	 * which could rarely be triggered at least on i.MX6SX connected
128 	 * to 800x480 DPI panel and i.MX8MM connected to DPI->DSI->LVDS
129 	 * bridged 1920x1080 panel (and likely on other setups too), where
130 	 * the image on the panel shifts to the right and wraps around.
131 	 * This happens either when the controller is enabled on boot or
132 	 * even later during run time. The condition does not correct
133 	 * itself automatically, i.e. the display image remains shifted.
134 	 *
135 	 * It seems this problem is known and is due to sporadic underflows
136 	 * of the LCDIF FIFO. While the LCDIF IP does have underflow/overflow
137 	 * IRQs, neither of the IRQs trigger and neither IRQ status bit is
138 	 * asserted when this condition occurs.
139 	 *
140 	 * All known revisions of the LCDIF IP have CTRL1 RECOVER_ON_UNDERFLOW
141 	 * bit, which is described in the reference manual since i.MX23 as
142 	 * "
143 	 *   Set this bit to enable the LCDIF block to recover in the next
144 	 *   field/frame if there was an underflow in the current field/frame.
145 	 * "
146 	 * Enable this bit to mitigate the sporadic underflows.
147 	 */
148 	reg = readl(mxsfb->base + LCDC_CTRL1);
149 	reg |= CTRL1_RECOVER_ON_UNDERFLOW;
150 	writel(reg, mxsfb->base + LCDC_CTRL1);
151 
152 	writel(CTRL_RUN, mxsfb->base + LCDC_CTRL + REG_SET);
153 }
154 
155 static void mxsfb_disable_controller(struct mxsfb_drm_private *mxsfb)
156 {
157 	u32 reg;
158 
159 	/*
160 	 * Even if we disable the controller here, it will still continue
161 	 * until its FIFOs are running out of data
162 	 */
163 	writel(CTRL_DOTCLK_MODE, mxsfb->base + LCDC_CTRL + REG_CLR);
164 
165 	readl_poll_timeout(mxsfb->base + LCDC_CTRL, reg, !(reg & CTRL_RUN),
166 			   0, 1000);
167 
168 	reg = readl(mxsfb->base + LCDC_VDCTRL4);
169 	reg &= ~VDCTRL4_SYNC_SIGNALS_ON;
170 	writel(reg, mxsfb->base + LCDC_VDCTRL4);
171 
172 	clk_disable_unprepare(mxsfb->clk);
173 	if (mxsfb->clk_disp_axi)
174 		clk_disable_unprepare(mxsfb->clk_disp_axi);
175 }
176 
177 /*
178  * Clear the bit and poll it cleared.  This is usually called with
179  * a reset address and mask being either SFTRST(bit 31) or CLKGATE
180  * (bit 30).
181  */
182 static int clear_poll_bit(void __iomem *addr, u32 mask)
183 {
184 	u32 reg;
185 
186 	writel(mask, addr + REG_CLR);
187 	return readl_poll_timeout(addr, reg, !(reg & mask), 0, RESET_TIMEOUT);
188 }
189 
190 static int mxsfb_reset_block(struct mxsfb_drm_private *mxsfb)
191 {
192 	int ret;
193 
194 	ret = clear_poll_bit(mxsfb->base + LCDC_CTRL, CTRL_SFTRST);
195 	if (ret)
196 		return ret;
197 
198 	writel(CTRL_CLKGATE, mxsfb->base + LCDC_CTRL + REG_CLR);
199 
200 	ret = clear_poll_bit(mxsfb->base + LCDC_CTRL, CTRL_SFTRST);
201 	if (ret)
202 		return ret;
203 
204 	return clear_poll_bit(mxsfb->base + LCDC_CTRL, CTRL_CLKGATE);
205 }
206 
207 static dma_addr_t mxsfb_get_fb_paddr(struct drm_plane *plane)
208 {
209 	struct drm_framebuffer *fb = plane->state->fb;
210 	struct drm_gem_cma_object *gem;
211 
212 	if (!fb)
213 		return 0;
214 
215 	gem = drm_fb_cma_get_gem_obj(fb, 0);
216 	if (!gem)
217 		return 0;
218 
219 	return gem->paddr;
220 }
221 
222 static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb,
223 				     const u32 bus_format)
224 {
225 	struct drm_device *drm = mxsfb->crtc.dev;
226 	struct drm_display_mode *m = &mxsfb->crtc.state->adjusted_mode;
227 	u32 bus_flags = mxsfb->connector->display_info.bus_flags;
228 	u32 vdctrl0, vsync_pulse_len, hsync_pulse_len;
229 	int err;
230 
231 	/*
232 	 * It seems, you can't re-program the controller if it is still
233 	 * running. This may lead to shifted pictures (FIFO issue?), so
234 	 * first stop the controller and drain its FIFOs.
235 	 */
236 
237 	/* Mandatory eLCDIF reset as per the Reference Manual */
238 	err = mxsfb_reset_block(mxsfb);
239 	if (err)
240 		return;
241 
242 	/* Clear the FIFOs */
243 	writel(CTRL1_FIFO_CLEAR, mxsfb->base + LCDC_CTRL1 + REG_SET);
244 	readl(mxsfb->base + LCDC_CTRL1);
245 	writel(CTRL1_FIFO_CLEAR, mxsfb->base + LCDC_CTRL1 + REG_CLR);
246 	readl(mxsfb->base + LCDC_CTRL1);
247 
248 	if (mxsfb->devdata->has_overlay)
249 		writel(0, mxsfb->base + LCDC_AS_CTRL);
250 
251 	mxsfb_set_formats(mxsfb, bus_format);
252 
253 	clk_set_rate(mxsfb->clk, m->crtc_clock * 1000);
254 
255 	if (mxsfb->bridge && mxsfb->bridge->timings)
256 		bus_flags = mxsfb->bridge->timings->input_bus_flags;
257 
258 	DRM_DEV_DEBUG_DRIVER(drm->dev, "Pixel clock: %dkHz (actual: %dkHz)\n",
259 			     m->crtc_clock,
260 			     (int)(clk_get_rate(mxsfb->clk) / 1000));
261 	DRM_DEV_DEBUG_DRIVER(drm->dev, "Connector bus_flags: 0x%08X\n",
262 			     bus_flags);
263 	DRM_DEV_DEBUG_DRIVER(drm->dev, "Mode flags: 0x%08X\n", m->flags);
264 
265 	writel(TRANSFER_COUNT_SET_VCOUNT(m->crtc_vdisplay) |
266 	       TRANSFER_COUNT_SET_HCOUNT(m->crtc_hdisplay),
267 	       mxsfb->base + mxsfb->devdata->transfer_count);
268 
269 	vsync_pulse_len = m->crtc_vsync_end - m->crtc_vsync_start;
270 
271 	vdctrl0 = VDCTRL0_ENABLE_PRESENT |	/* Always in DOTCLOCK mode */
272 		  VDCTRL0_VSYNC_PERIOD_UNIT |
273 		  VDCTRL0_VSYNC_PULSE_WIDTH_UNIT |
274 		  VDCTRL0_SET_VSYNC_PULSE_WIDTH(vsync_pulse_len);
275 	if (m->flags & DRM_MODE_FLAG_PHSYNC)
276 		vdctrl0 |= VDCTRL0_HSYNC_ACT_HIGH;
277 	if (m->flags & DRM_MODE_FLAG_PVSYNC)
278 		vdctrl0 |= VDCTRL0_VSYNC_ACT_HIGH;
279 	/* Make sure Data Enable is high active by default */
280 	if (!(bus_flags & DRM_BUS_FLAG_DE_LOW))
281 		vdctrl0 |= VDCTRL0_ENABLE_ACT_HIGH;
282 	/*
283 	 * DRM_BUS_FLAG_PIXDATA_DRIVE_ defines are controller centric,
284 	 * controllers VDCTRL0_DOTCLK is display centric.
285 	 * Drive on positive edge       -> display samples on falling edge
286 	 * DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE -> VDCTRL0_DOTCLK_ACT_FALLING
287 	 */
288 	if (bus_flags & DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE)
289 		vdctrl0 |= VDCTRL0_DOTCLK_ACT_FALLING;
290 
291 	writel(vdctrl0, mxsfb->base + LCDC_VDCTRL0);
292 
293 	/* Frame length in lines. */
294 	writel(m->crtc_vtotal, mxsfb->base + LCDC_VDCTRL1);
295 
296 	/* Line length in units of clocks or pixels. */
297 	hsync_pulse_len = m->crtc_hsync_end - m->crtc_hsync_start;
298 	writel(set_hsync_pulse_width(mxsfb, hsync_pulse_len) |
299 	       VDCTRL2_SET_HSYNC_PERIOD(m->crtc_htotal),
300 	       mxsfb->base + LCDC_VDCTRL2);
301 
302 	writel(SET_HOR_WAIT_CNT(m->crtc_htotal - m->crtc_hsync_start) |
303 	       SET_VERT_WAIT_CNT(m->crtc_vtotal - m->crtc_vsync_start),
304 	       mxsfb->base + LCDC_VDCTRL3);
305 
306 	writel(SET_DOTCLK_H_VALID_DATA_CNT(m->hdisplay),
307 	       mxsfb->base + LCDC_VDCTRL4);
308 }
309 
310 static int mxsfb_crtc_atomic_check(struct drm_crtc *crtc,
311 				   struct drm_atomic_state *state)
312 {
313 	struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state,
314 									  crtc);
315 	bool has_primary = crtc_state->plane_mask &
316 			   drm_plane_mask(crtc->primary);
317 
318 	/* The primary plane has to be enabled when the CRTC is active. */
319 	if (crtc_state->active && !has_primary)
320 		return -EINVAL;
321 
322 	/* TODO: Is this needed ? */
323 	return drm_atomic_add_affected_planes(state, crtc);
324 }
325 
326 static void mxsfb_crtc_atomic_flush(struct drm_crtc *crtc,
327 				    struct drm_atomic_state *state)
328 {
329 	struct drm_pending_vblank_event *event;
330 
331 	event = crtc->state->event;
332 	crtc->state->event = NULL;
333 
334 	if (!event)
335 		return;
336 
337 	spin_lock_irq(&crtc->dev->event_lock);
338 	if (drm_crtc_vblank_get(crtc) == 0)
339 		drm_crtc_arm_vblank_event(crtc, event);
340 	else
341 		drm_crtc_send_vblank_event(crtc, event);
342 	spin_unlock_irq(&crtc->dev->event_lock);
343 }
344 
345 static void mxsfb_crtc_atomic_enable(struct drm_crtc *crtc,
346 				     struct drm_atomic_state *state)
347 {
348 	struct mxsfb_drm_private *mxsfb = to_mxsfb_drm_private(crtc->dev);
349 	struct drm_bridge_state *bridge_state;
350 	struct drm_device *drm = mxsfb->drm;
351 	u32 bus_format = 0;
352 	dma_addr_t paddr;
353 
354 	pm_runtime_get_sync(drm->dev);
355 	mxsfb_enable_axi_clk(mxsfb);
356 
357 	drm_crtc_vblank_on(crtc);
358 
359 	/* If there is a bridge attached to the LCDIF, use its bus format */
360 	if (mxsfb->bridge) {
361 		bridge_state =
362 			drm_atomic_get_new_bridge_state(state,
363 							mxsfb->bridge);
364 		bus_format = bridge_state->input_bus_cfg.format;
365 		if (bus_format == MEDIA_BUS_FMT_FIXED) {
366 			dev_warn_once(drm->dev,
367 				      "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
368 				      "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n");
369 			bus_format = MEDIA_BUS_FMT_RGB888_1X24;
370 		}
371 	}
372 
373 	/* If there is no bridge, use bus format from connector */
374 	if (!bus_format && mxsfb->connector->display_info.num_bus_formats)
375 		bus_format = mxsfb->connector->display_info.bus_formats[0];
376 
377 	/* If all else fails, default to RGB888_1X24 */
378 	if (!bus_format)
379 		bus_format = MEDIA_BUS_FMT_RGB888_1X24;
380 
381 	mxsfb_crtc_mode_set_nofb(mxsfb, bus_format);
382 
383 	/* Write cur_buf as well to avoid an initial corrupt frame */
384 	paddr = mxsfb_get_fb_paddr(crtc->primary);
385 	if (paddr) {
386 		writel(paddr, mxsfb->base + mxsfb->devdata->cur_buf);
387 		writel(paddr, mxsfb->base + mxsfb->devdata->next_buf);
388 	}
389 
390 	mxsfb_enable_controller(mxsfb);
391 }
392 
393 static void mxsfb_crtc_atomic_disable(struct drm_crtc *crtc,
394 				      struct drm_atomic_state *state)
395 {
396 	struct mxsfb_drm_private *mxsfb = to_mxsfb_drm_private(crtc->dev);
397 	struct drm_device *drm = mxsfb->drm;
398 	struct drm_pending_vblank_event *event;
399 
400 	mxsfb_disable_controller(mxsfb);
401 
402 	spin_lock_irq(&drm->event_lock);
403 	event = crtc->state->event;
404 	if (event) {
405 		crtc->state->event = NULL;
406 		drm_crtc_send_vblank_event(crtc, event);
407 	}
408 	spin_unlock_irq(&drm->event_lock);
409 
410 	drm_crtc_vblank_off(crtc);
411 
412 	mxsfb_disable_axi_clk(mxsfb);
413 	pm_runtime_put_sync(drm->dev);
414 }
415 
416 static int mxsfb_crtc_enable_vblank(struct drm_crtc *crtc)
417 {
418 	struct mxsfb_drm_private *mxsfb = to_mxsfb_drm_private(crtc->dev);
419 
420 	/* Clear and enable VBLANK IRQ */
421 	writel(CTRL1_CUR_FRAME_DONE_IRQ, mxsfb->base + LCDC_CTRL1 + REG_CLR);
422 	writel(CTRL1_CUR_FRAME_DONE_IRQ_EN, mxsfb->base + LCDC_CTRL1 + REG_SET);
423 
424 	return 0;
425 }
426 
427 static void mxsfb_crtc_disable_vblank(struct drm_crtc *crtc)
428 {
429 	struct mxsfb_drm_private *mxsfb = to_mxsfb_drm_private(crtc->dev);
430 
431 	/* Disable and clear VBLANK IRQ */
432 	writel(CTRL1_CUR_FRAME_DONE_IRQ_EN, mxsfb->base + LCDC_CTRL1 + REG_CLR);
433 	writel(CTRL1_CUR_FRAME_DONE_IRQ, mxsfb->base + LCDC_CTRL1 + REG_CLR);
434 }
435 
436 static const struct drm_crtc_helper_funcs mxsfb_crtc_helper_funcs = {
437 	.atomic_check = mxsfb_crtc_atomic_check,
438 	.atomic_flush = mxsfb_crtc_atomic_flush,
439 	.atomic_enable = mxsfb_crtc_atomic_enable,
440 	.atomic_disable = mxsfb_crtc_atomic_disable,
441 };
442 
443 static const struct drm_crtc_funcs mxsfb_crtc_funcs = {
444 	.reset = drm_atomic_helper_crtc_reset,
445 	.destroy = drm_crtc_cleanup,
446 	.set_config = drm_atomic_helper_set_config,
447 	.page_flip = drm_atomic_helper_page_flip,
448 	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
449 	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
450 	.enable_vblank = mxsfb_crtc_enable_vblank,
451 	.disable_vblank = mxsfb_crtc_disable_vblank,
452 };
453 
454 /* -----------------------------------------------------------------------------
455  * Encoder
456  */
457 
458 static const struct drm_encoder_funcs mxsfb_encoder_funcs = {
459 	.destroy = drm_encoder_cleanup,
460 };
461 
462 /* -----------------------------------------------------------------------------
463  * Planes
464  */
465 
466 static int mxsfb_plane_atomic_check(struct drm_plane *plane,
467 				    struct drm_atomic_state *state)
468 {
469 	struct drm_plane_state *plane_state = drm_atomic_get_new_plane_state(state,
470 									     plane);
471 	struct mxsfb_drm_private *mxsfb = to_mxsfb_drm_private(plane->dev);
472 	struct drm_crtc_state *crtc_state;
473 
474 	crtc_state = drm_atomic_get_new_crtc_state(state,
475 						   &mxsfb->crtc);
476 
477 	return drm_atomic_helper_check_plane_state(plane_state, crtc_state,
478 						   DRM_PLANE_HELPER_NO_SCALING,
479 						   DRM_PLANE_HELPER_NO_SCALING,
480 						   false, true);
481 }
482 
483 static void mxsfb_plane_primary_atomic_update(struct drm_plane *plane,
484 					      struct drm_atomic_state *state)
485 {
486 	struct mxsfb_drm_private *mxsfb = to_mxsfb_drm_private(plane->dev);
487 	dma_addr_t paddr;
488 
489 	paddr = mxsfb_get_fb_paddr(plane);
490 	if (paddr)
491 		writel(paddr, mxsfb->base + mxsfb->devdata->next_buf);
492 }
493 
494 static void mxsfb_plane_overlay_atomic_update(struct drm_plane *plane,
495 					      struct drm_atomic_state *state)
496 {
497 	struct drm_plane_state *old_pstate = drm_atomic_get_old_plane_state(state,
498 									    plane);
499 	struct mxsfb_drm_private *mxsfb = to_mxsfb_drm_private(plane->dev);
500 	struct drm_plane_state *new_pstate = drm_atomic_get_new_plane_state(state,
501 									    plane);
502 	dma_addr_t paddr;
503 	u32 ctrl;
504 
505 	paddr = mxsfb_get_fb_paddr(plane);
506 	if (!paddr) {
507 		writel(0, mxsfb->base + LCDC_AS_CTRL);
508 		return;
509 	}
510 
511 	/*
512 	 * HACK: The hardware seems to output 64 bytes of data of unknown
513 	 * origin, and then to proceed with the framebuffer. Until the reason
514 	 * is understood, live with the 16 initial invalid pixels on the first
515 	 * line and start 64 bytes within the framebuffer.
516 	 */
517 	paddr += 64;
518 
519 	writel(paddr, mxsfb->base + LCDC_AS_NEXT_BUF);
520 
521 	/*
522 	 * If the plane was previously disabled, write LCDC_AS_BUF as well to
523 	 * provide the first buffer.
524 	 */
525 	if (!old_pstate->fb)
526 		writel(paddr, mxsfb->base + LCDC_AS_BUF);
527 
528 	ctrl = AS_CTRL_AS_ENABLE | AS_CTRL_ALPHA(255);
529 
530 	switch (new_pstate->fb->format->format) {
531 	case DRM_FORMAT_XRGB4444:
532 		ctrl |= AS_CTRL_FORMAT_RGB444 | AS_CTRL_ALPHA_CTRL_OVERRIDE;
533 		break;
534 	case DRM_FORMAT_ARGB4444:
535 		ctrl |= AS_CTRL_FORMAT_ARGB4444 | AS_CTRL_ALPHA_CTRL_EMBEDDED;
536 		break;
537 	case DRM_FORMAT_XRGB1555:
538 		ctrl |= AS_CTRL_FORMAT_RGB555 | AS_CTRL_ALPHA_CTRL_OVERRIDE;
539 		break;
540 	case DRM_FORMAT_ARGB1555:
541 		ctrl |= AS_CTRL_FORMAT_ARGB1555 | AS_CTRL_ALPHA_CTRL_EMBEDDED;
542 		break;
543 	case DRM_FORMAT_RGB565:
544 		ctrl |= AS_CTRL_FORMAT_RGB565 | AS_CTRL_ALPHA_CTRL_OVERRIDE;
545 		break;
546 	case DRM_FORMAT_XRGB8888:
547 		ctrl |= AS_CTRL_FORMAT_RGB888 | AS_CTRL_ALPHA_CTRL_OVERRIDE;
548 		break;
549 	case DRM_FORMAT_ARGB8888:
550 		ctrl |= AS_CTRL_FORMAT_ARGB8888 | AS_CTRL_ALPHA_CTRL_EMBEDDED;
551 		break;
552 	}
553 
554 	writel(ctrl, mxsfb->base + LCDC_AS_CTRL);
555 }
556 
557 static bool mxsfb_format_mod_supported(struct drm_plane *plane,
558 				       uint32_t format,
559 				       uint64_t modifier)
560 {
561 	return modifier == DRM_FORMAT_MOD_LINEAR;
562 }
563 
564 static const struct drm_plane_helper_funcs mxsfb_plane_primary_helper_funcs = {
565 	.atomic_check = mxsfb_plane_atomic_check,
566 	.atomic_update = mxsfb_plane_primary_atomic_update,
567 };
568 
569 static const struct drm_plane_helper_funcs mxsfb_plane_overlay_helper_funcs = {
570 	.atomic_check = mxsfb_plane_atomic_check,
571 	.atomic_update = mxsfb_plane_overlay_atomic_update,
572 };
573 
574 static const struct drm_plane_funcs mxsfb_plane_funcs = {
575 	.format_mod_supported	= mxsfb_format_mod_supported,
576 	.update_plane		= drm_atomic_helper_update_plane,
577 	.disable_plane		= drm_atomic_helper_disable_plane,
578 	.destroy		= drm_plane_cleanup,
579 	.reset			= drm_atomic_helper_plane_reset,
580 	.atomic_duplicate_state	= drm_atomic_helper_plane_duplicate_state,
581 	.atomic_destroy_state	= drm_atomic_helper_plane_destroy_state,
582 };
583 
584 static const uint32_t mxsfb_primary_plane_formats[] = {
585 	DRM_FORMAT_RGB565,
586 	DRM_FORMAT_XRGB8888,
587 };
588 
589 static const uint32_t mxsfb_overlay_plane_formats[] = {
590 	DRM_FORMAT_XRGB4444,
591 	DRM_FORMAT_ARGB4444,
592 	DRM_FORMAT_XRGB1555,
593 	DRM_FORMAT_ARGB1555,
594 	DRM_FORMAT_RGB565,
595 	DRM_FORMAT_XRGB8888,
596 	DRM_FORMAT_ARGB8888,
597 };
598 
599 static const uint64_t mxsfb_modifiers[] = {
600 	DRM_FORMAT_MOD_LINEAR,
601 	DRM_FORMAT_MOD_INVALID
602 };
603 
604 /* -----------------------------------------------------------------------------
605  * Initialization
606  */
607 
608 int mxsfb_kms_init(struct mxsfb_drm_private *mxsfb)
609 {
610 	struct drm_encoder *encoder = &mxsfb->encoder;
611 	struct drm_crtc *crtc = &mxsfb->crtc;
612 	int ret;
613 
614 	drm_plane_helper_add(&mxsfb->planes.primary,
615 			     &mxsfb_plane_primary_helper_funcs);
616 	ret = drm_universal_plane_init(mxsfb->drm, &mxsfb->planes.primary, 1,
617 				       &mxsfb_plane_funcs,
618 				       mxsfb_primary_plane_formats,
619 				       ARRAY_SIZE(mxsfb_primary_plane_formats),
620 				       mxsfb_modifiers, DRM_PLANE_TYPE_PRIMARY,
621 				       NULL);
622 	if (ret)
623 		return ret;
624 
625 	if (mxsfb->devdata->has_overlay) {
626 		drm_plane_helper_add(&mxsfb->planes.overlay,
627 				     &mxsfb_plane_overlay_helper_funcs);
628 		ret = drm_universal_plane_init(mxsfb->drm,
629 					       &mxsfb->planes.overlay, 1,
630 					       &mxsfb_plane_funcs,
631 					       mxsfb_overlay_plane_formats,
632 					       ARRAY_SIZE(mxsfb_overlay_plane_formats),
633 					       mxsfb_modifiers, DRM_PLANE_TYPE_OVERLAY,
634 					       NULL);
635 		if (ret)
636 			return ret;
637 	}
638 
639 	drm_crtc_helper_add(crtc, &mxsfb_crtc_helper_funcs);
640 	ret = drm_crtc_init_with_planes(mxsfb->drm, crtc,
641 					&mxsfb->planes.primary, NULL,
642 					&mxsfb_crtc_funcs, NULL);
643 	if (ret)
644 		return ret;
645 
646 	encoder->possible_crtcs = drm_crtc_mask(crtc);
647 	return drm_encoder_init(mxsfb->drm, encoder, &mxsfb_encoder_funcs,
648 				DRM_MODE_ENCODER_NONE, NULL);
649 }
650