xref: /openbmc/linux/drivers/gpu/drm/mxsfb/mxsfb_kms.c (revision f05643a0)
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_set_mode(struct mxsfb_drm_private *mxsfb, u32 bus_flags)
100 {
101 	struct drm_display_mode *m = &mxsfb->crtc.state->adjusted_mode;
102 	u32 vdctrl0, vsync_pulse_len, hsync_pulse_len;
103 
104 	writel(TRANSFER_COUNT_SET_VCOUNT(m->crtc_vdisplay) |
105 	       TRANSFER_COUNT_SET_HCOUNT(m->crtc_hdisplay),
106 	       mxsfb->base + mxsfb->devdata->transfer_count);
107 
108 	vsync_pulse_len = m->crtc_vsync_end - m->crtc_vsync_start;
109 
110 	vdctrl0 = VDCTRL0_ENABLE_PRESENT |	/* Always in DOTCLOCK mode */
111 		  VDCTRL0_VSYNC_PERIOD_UNIT |
112 		  VDCTRL0_VSYNC_PULSE_WIDTH_UNIT |
113 		  VDCTRL0_SET_VSYNC_PULSE_WIDTH(vsync_pulse_len);
114 	if (m->flags & DRM_MODE_FLAG_PHSYNC)
115 		vdctrl0 |= VDCTRL0_HSYNC_ACT_HIGH;
116 	if (m->flags & DRM_MODE_FLAG_PVSYNC)
117 		vdctrl0 |= VDCTRL0_VSYNC_ACT_HIGH;
118 	/* Make sure Data Enable is high active by default */
119 	if (!(bus_flags & DRM_BUS_FLAG_DE_LOW))
120 		vdctrl0 |= VDCTRL0_ENABLE_ACT_HIGH;
121 	/*
122 	 * DRM_BUS_FLAG_PIXDATA_DRIVE_ defines are controller centric,
123 	 * controllers VDCTRL0_DOTCLK is display centric.
124 	 * Drive on positive edge       -> display samples on falling edge
125 	 * DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE -> VDCTRL0_DOTCLK_ACT_FALLING
126 	 */
127 	if (bus_flags & DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE)
128 		vdctrl0 |= VDCTRL0_DOTCLK_ACT_FALLING;
129 
130 	writel(vdctrl0, mxsfb->base + LCDC_VDCTRL0);
131 
132 	/* Frame length in lines. */
133 	writel(m->crtc_vtotal, mxsfb->base + LCDC_VDCTRL1);
134 
135 	/* Line length in units of clocks or pixels. */
136 	hsync_pulse_len = m->crtc_hsync_end - m->crtc_hsync_start;
137 	writel(set_hsync_pulse_width(mxsfb, hsync_pulse_len) |
138 	       VDCTRL2_SET_HSYNC_PERIOD(m->crtc_htotal),
139 	       mxsfb->base + LCDC_VDCTRL2);
140 
141 	writel(SET_HOR_WAIT_CNT(m->crtc_htotal - m->crtc_hsync_start) |
142 	       SET_VERT_WAIT_CNT(m->crtc_vtotal - m->crtc_vsync_start),
143 	       mxsfb->base + LCDC_VDCTRL3);
144 
145 	writel(SET_DOTCLK_H_VALID_DATA_CNT(m->hdisplay),
146 	       mxsfb->base + LCDC_VDCTRL4);
147 
148 }
149 
150 static void mxsfb_enable_controller(struct mxsfb_drm_private *mxsfb)
151 {
152 	u32 reg;
153 
154 	if (mxsfb->clk_disp_axi)
155 		clk_prepare_enable(mxsfb->clk_disp_axi);
156 	clk_prepare_enable(mxsfb->clk);
157 
158 	/* Increase number of outstanding requests on all supported IPs */
159 	if (mxsfb->devdata->has_ctrl2) {
160 		reg = readl(mxsfb->base + LCDC_V4_CTRL2);
161 		reg &= ~CTRL2_SET_OUTSTANDING_REQS_MASK;
162 		reg |= CTRL2_SET_OUTSTANDING_REQS_16;
163 		writel(reg, mxsfb->base + LCDC_V4_CTRL2);
164 	}
165 
166 	/* If it was disabled, re-enable the mode again */
167 	writel(CTRL_DOTCLK_MODE, mxsfb->base + LCDC_CTRL + REG_SET);
168 
169 	/* Enable the SYNC signals first, then the DMA engine */
170 	reg = readl(mxsfb->base + LCDC_VDCTRL4);
171 	reg |= VDCTRL4_SYNC_SIGNALS_ON;
172 	writel(reg, mxsfb->base + LCDC_VDCTRL4);
173 
174 	/*
175 	 * Enable recovery on underflow.
176 	 *
177 	 * There is some sort of corner case behavior of the controller,
178 	 * which could rarely be triggered at least on i.MX6SX connected
179 	 * to 800x480 DPI panel and i.MX8MM connected to DPI->DSI->LVDS
180 	 * bridged 1920x1080 panel (and likely on other setups too), where
181 	 * the image on the panel shifts to the right and wraps around.
182 	 * This happens either when the controller is enabled on boot or
183 	 * even later during run time. The condition does not correct
184 	 * itself automatically, i.e. the display image remains shifted.
185 	 *
186 	 * It seems this problem is known and is due to sporadic underflows
187 	 * of the LCDIF FIFO. While the LCDIF IP does have underflow/overflow
188 	 * IRQs, neither of the IRQs trigger and neither IRQ status bit is
189 	 * asserted when this condition occurs.
190 	 *
191 	 * All known revisions of the LCDIF IP have CTRL1 RECOVER_ON_UNDERFLOW
192 	 * bit, which is described in the reference manual since i.MX23 as
193 	 * "
194 	 *   Set this bit to enable the LCDIF block to recover in the next
195 	 *   field/frame if there was an underflow in the current field/frame.
196 	 * "
197 	 * Enable this bit to mitigate the sporadic underflows.
198 	 */
199 	reg = readl(mxsfb->base + LCDC_CTRL1);
200 	reg |= CTRL1_RECOVER_ON_UNDERFLOW;
201 	writel(reg, mxsfb->base + LCDC_CTRL1);
202 
203 	writel(CTRL_RUN, mxsfb->base + LCDC_CTRL + REG_SET);
204 }
205 
206 static void mxsfb_disable_controller(struct mxsfb_drm_private *mxsfb)
207 {
208 	u32 reg;
209 
210 	/*
211 	 * Even if we disable the controller here, it will still continue
212 	 * until its FIFOs are running out of data
213 	 */
214 	writel(CTRL_DOTCLK_MODE, mxsfb->base + LCDC_CTRL + REG_CLR);
215 
216 	readl_poll_timeout(mxsfb->base + LCDC_CTRL, reg, !(reg & CTRL_RUN),
217 			   0, 1000);
218 
219 	reg = readl(mxsfb->base + LCDC_VDCTRL4);
220 	reg &= ~VDCTRL4_SYNC_SIGNALS_ON;
221 	writel(reg, mxsfb->base + LCDC_VDCTRL4);
222 
223 	clk_disable_unprepare(mxsfb->clk);
224 	if (mxsfb->clk_disp_axi)
225 		clk_disable_unprepare(mxsfb->clk_disp_axi);
226 }
227 
228 /*
229  * Clear the bit and poll it cleared.  This is usually called with
230  * a reset address and mask being either SFTRST(bit 31) or CLKGATE
231  * (bit 30).
232  */
233 static int clear_poll_bit(void __iomem *addr, u32 mask)
234 {
235 	u32 reg;
236 
237 	writel(mask, addr + REG_CLR);
238 	return readl_poll_timeout(addr, reg, !(reg & mask), 0, RESET_TIMEOUT);
239 }
240 
241 static int mxsfb_reset_block(struct mxsfb_drm_private *mxsfb)
242 {
243 	int ret;
244 
245 	/*
246 	 * It seems, you can't re-program the controller if it is still
247 	 * running. This may lead to shifted pictures (FIFO issue?), so
248 	 * first stop the controller and drain its FIFOs.
249 	 */
250 
251 	ret = clear_poll_bit(mxsfb->base + LCDC_CTRL, CTRL_SFTRST);
252 	if (ret)
253 		return ret;
254 
255 	writel(CTRL_CLKGATE, mxsfb->base + LCDC_CTRL + REG_CLR);
256 
257 	ret = clear_poll_bit(mxsfb->base + LCDC_CTRL, CTRL_SFTRST);
258 	if (ret)
259 		return ret;
260 
261 	ret = clear_poll_bit(mxsfb->base + LCDC_CTRL, CTRL_CLKGATE);
262 	if (ret)
263 		return ret;
264 
265 	/* Clear the FIFOs */
266 	writel(CTRL1_FIFO_CLEAR, mxsfb->base + LCDC_CTRL1 + REG_SET);
267 	readl(mxsfb->base + LCDC_CTRL1);
268 	writel(CTRL1_FIFO_CLEAR, mxsfb->base + LCDC_CTRL1 + REG_CLR);
269 	readl(mxsfb->base + LCDC_CTRL1);
270 
271 	if (mxsfb->devdata->has_overlay)
272 		writel(0, mxsfb->base + LCDC_AS_CTRL);
273 
274 	return 0;
275 }
276 
277 static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb,
278 				     struct drm_bridge_state *bridge_state,
279 				     const u32 bus_format)
280 {
281 	struct drm_device *drm = mxsfb->crtc.dev;
282 	struct drm_display_mode *m = &mxsfb->crtc.state->adjusted_mode;
283 	u32 bus_flags = mxsfb->connector->display_info.bus_flags;
284 	int err;
285 
286 	if (mxsfb->bridge && mxsfb->bridge->timings)
287 		bus_flags = mxsfb->bridge->timings->input_bus_flags;
288 	else if (bridge_state)
289 		bus_flags = bridge_state->input_bus_cfg.flags;
290 
291 	DRM_DEV_DEBUG_DRIVER(drm->dev, "Pixel clock: %dkHz (actual: %dkHz)\n",
292 			     m->crtc_clock,
293 			     (int)(clk_get_rate(mxsfb->clk) / 1000));
294 	DRM_DEV_DEBUG_DRIVER(drm->dev, "Connector bus_flags: 0x%08X\n",
295 			     bus_flags);
296 	DRM_DEV_DEBUG_DRIVER(drm->dev, "Mode flags: 0x%08X\n", m->flags);
297 
298 	/* Mandatory eLCDIF reset as per the Reference Manual */
299 	err = mxsfb_reset_block(mxsfb);
300 	if (err)
301 		return;
302 
303 	mxsfb_set_formats(mxsfb, bus_format);
304 
305 	clk_set_rate(mxsfb->clk, m->crtc_clock * 1000);
306 
307 	mxsfb_set_mode(mxsfb, bus_flags);
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_plane_state *new_pstate = drm_atomic_get_new_plane_state(state,
350 									    crtc->primary);
351 	struct drm_bridge_state *bridge_state = NULL;
352 	struct drm_device *drm = mxsfb->drm;
353 	u32 bus_format = 0;
354 	dma_addr_t paddr;
355 
356 	pm_runtime_get_sync(drm->dev);
357 	mxsfb_enable_axi_clk(mxsfb);
358 
359 	drm_crtc_vblank_on(crtc);
360 
361 	/* If there is a bridge attached to the LCDIF, use its bus format */
362 	if (mxsfb->bridge) {
363 		bridge_state =
364 			drm_atomic_get_new_bridge_state(state,
365 							mxsfb->bridge);
366 		if (!bridge_state)
367 			bus_format = MEDIA_BUS_FMT_FIXED;
368 		else
369 			bus_format = bridge_state->input_bus_cfg.format;
370 
371 		if (bus_format == MEDIA_BUS_FMT_FIXED) {
372 			dev_warn_once(drm->dev,
373 				      "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n"
374 				      "Please fix bridge driver by handling atomic_get_input_bus_fmts.\n");
375 			bus_format = MEDIA_BUS_FMT_RGB888_1X24;
376 		}
377 	}
378 
379 	/* If there is no bridge, use bus format from connector */
380 	if (!bus_format && mxsfb->connector->display_info.num_bus_formats)
381 		bus_format = mxsfb->connector->display_info.bus_formats[0];
382 
383 	/* If all else fails, default to RGB888_1X24 */
384 	if (!bus_format)
385 		bus_format = MEDIA_BUS_FMT_RGB888_1X24;
386 
387 	mxsfb_crtc_mode_set_nofb(mxsfb, bridge_state, bus_format);
388 
389 	/* Write cur_buf as well to avoid an initial corrupt frame */
390 	paddr = drm_fb_cma_get_gem_addr(new_pstate->fb, new_pstate, 0);
391 	if (paddr) {
392 		writel(paddr, mxsfb->base + mxsfb->devdata->cur_buf);
393 		writel(paddr, mxsfb->base + mxsfb->devdata->next_buf);
394 	}
395 
396 	mxsfb_enable_controller(mxsfb);
397 }
398 
399 static void mxsfb_crtc_atomic_disable(struct drm_crtc *crtc,
400 				      struct drm_atomic_state *state)
401 {
402 	struct mxsfb_drm_private *mxsfb = to_mxsfb_drm_private(crtc->dev);
403 	struct drm_device *drm = mxsfb->drm;
404 	struct drm_pending_vblank_event *event;
405 
406 	mxsfb_disable_controller(mxsfb);
407 
408 	spin_lock_irq(&drm->event_lock);
409 	event = crtc->state->event;
410 	if (event) {
411 		crtc->state->event = NULL;
412 		drm_crtc_send_vblank_event(crtc, event);
413 	}
414 	spin_unlock_irq(&drm->event_lock);
415 
416 	drm_crtc_vblank_off(crtc);
417 
418 	mxsfb_disable_axi_clk(mxsfb);
419 	pm_runtime_put_sync(drm->dev);
420 }
421 
422 static int mxsfb_crtc_enable_vblank(struct drm_crtc *crtc)
423 {
424 	struct mxsfb_drm_private *mxsfb = to_mxsfb_drm_private(crtc->dev);
425 
426 	/* Clear and enable VBLANK IRQ */
427 	writel(CTRL1_CUR_FRAME_DONE_IRQ, mxsfb->base + LCDC_CTRL1 + REG_CLR);
428 	writel(CTRL1_CUR_FRAME_DONE_IRQ_EN, mxsfb->base + LCDC_CTRL1 + REG_SET);
429 
430 	return 0;
431 }
432 
433 static void mxsfb_crtc_disable_vblank(struct drm_crtc *crtc)
434 {
435 	struct mxsfb_drm_private *mxsfb = to_mxsfb_drm_private(crtc->dev);
436 
437 	/* Disable and clear VBLANK IRQ */
438 	writel(CTRL1_CUR_FRAME_DONE_IRQ_EN, mxsfb->base + LCDC_CTRL1 + REG_CLR);
439 	writel(CTRL1_CUR_FRAME_DONE_IRQ, mxsfb->base + LCDC_CTRL1 + REG_CLR);
440 }
441 
442 static int mxsfb_crtc_set_crc_source(struct drm_crtc *crtc, const char *source)
443 {
444 	struct mxsfb_drm_private *mxsfb;
445 
446 	if (!crtc)
447 		return -ENODEV;
448 
449 	mxsfb = to_mxsfb_drm_private(crtc->dev);
450 
451 	if (source && strcmp(source, "auto") == 0)
452 		mxsfb->crc_active = true;
453 	else if (!source)
454 		mxsfb->crc_active = false;
455 	else
456 		return -EINVAL;
457 
458 	return 0;
459 }
460 
461 static int mxsfb_crtc_verify_crc_source(struct drm_crtc *crtc,
462 					const char *source, size_t *values_cnt)
463 {
464 	if (!crtc)
465 		return -ENODEV;
466 
467 	if (source && strcmp(source, "auto") != 0) {
468 		DRM_DEBUG_DRIVER("Unknown CRC source %s for %s\n",
469 				 source, crtc->name);
470 		return -EINVAL;
471 	}
472 
473 	*values_cnt = 1;
474 	return 0;
475 }
476 
477 static const struct drm_crtc_helper_funcs mxsfb_crtc_helper_funcs = {
478 	.atomic_check = mxsfb_crtc_atomic_check,
479 	.atomic_flush = mxsfb_crtc_atomic_flush,
480 	.atomic_enable = mxsfb_crtc_atomic_enable,
481 	.atomic_disable = mxsfb_crtc_atomic_disable,
482 };
483 
484 static const struct drm_crtc_funcs mxsfb_crtc_funcs = {
485 	.reset = drm_atomic_helper_crtc_reset,
486 	.destroy = drm_crtc_cleanup,
487 	.set_config = drm_atomic_helper_set_config,
488 	.page_flip = drm_atomic_helper_page_flip,
489 	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
490 	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
491 	.enable_vblank = mxsfb_crtc_enable_vblank,
492 	.disable_vblank = mxsfb_crtc_disable_vblank,
493 };
494 
495 static const struct drm_crtc_funcs mxsfb_crtc_with_crc_funcs = {
496 	.reset = drm_atomic_helper_crtc_reset,
497 	.destroy = drm_crtc_cleanup,
498 	.set_config = drm_atomic_helper_set_config,
499 	.page_flip = drm_atomic_helper_page_flip,
500 	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
501 	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
502 	.enable_vblank = mxsfb_crtc_enable_vblank,
503 	.disable_vblank = mxsfb_crtc_disable_vblank,
504 	.set_crc_source = mxsfb_crtc_set_crc_source,
505 	.verify_crc_source = mxsfb_crtc_verify_crc_source,
506 };
507 
508 /* -----------------------------------------------------------------------------
509  * Encoder
510  */
511 
512 static const struct drm_encoder_funcs mxsfb_encoder_funcs = {
513 	.destroy = drm_encoder_cleanup,
514 };
515 
516 /* -----------------------------------------------------------------------------
517  * Planes
518  */
519 
520 static int mxsfb_plane_atomic_check(struct drm_plane *plane,
521 				    struct drm_atomic_state *state)
522 {
523 	struct drm_plane_state *plane_state = drm_atomic_get_new_plane_state(state,
524 									     plane);
525 	struct mxsfb_drm_private *mxsfb = to_mxsfb_drm_private(plane->dev);
526 	struct drm_crtc_state *crtc_state;
527 
528 	crtc_state = drm_atomic_get_new_crtc_state(state,
529 						   &mxsfb->crtc);
530 
531 	return drm_atomic_helper_check_plane_state(plane_state, crtc_state,
532 						   DRM_PLANE_HELPER_NO_SCALING,
533 						   DRM_PLANE_HELPER_NO_SCALING,
534 						   false, true);
535 }
536 
537 static void mxsfb_plane_primary_atomic_update(struct drm_plane *plane,
538 					      struct drm_atomic_state *state)
539 {
540 	struct mxsfb_drm_private *mxsfb = to_mxsfb_drm_private(plane->dev);
541 	struct drm_plane_state *new_pstate = drm_atomic_get_new_plane_state(state,
542 									    plane);
543 	dma_addr_t paddr;
544 
545 	paddr = drm_fb_cma_get_gem_addr(new_pstate->fb, new_pstate, 0);
546 	if (paddr)
547 		writel(paddr, mxsfb->base + mxsfb->devdata->next_buf);
548 }
549 
550 static void mxsfb_plane_overlay_atomic_update(struct drm_plane *plane,
551 					      struct drm_atomic_state *state)
552 {
553 	struct drm_plane_state *old_pstate = drm_atomic_get_old_plane_state(state,
554 									    plane);
555 	struct mxsfb_drm_private *mxsfb = to_mxsfb_drm_private(plane->dev);
556 	struct drm_plane_state *new_pstate = drm_atomic_get_new_plane_state(state,
557 									    plane);
558 	dma_addr_t paddr;
559 	u32 ctrl;
560 
561 	paddr = drm_fb_cma_get_gem_addr(new_pstate->fb, new_pstate, 0);
562 	if (!paddr) {
563 		writel(0, mxsfb->base + LCDC_AS_CTRL);
564 		return;
565 	}
566 
567 	/*
568 	 * HACK: The hardware seems to output 64 bytes of data of unknown
569 	 * origin, and then to proceed with the framebuffer. Until the reason
570 	 * is understood, live with the 16 initial invalid pixels on the first
571 	 * line and start 64 bytes within the framebuffer.
572 	 */
573 	paddr += 64;
574 
575 	writel(paddr, mxsfb->base + LCDC_AS_NEXT_BUF);
576 
577 	/*
578 	 * If the plane was previously disabled, write LCDC_AS_BUF as well to
579 	 * provide the first buffer.
580 	 */
581 	if (!old_pstate->fb)
582 		writel(paddr, mxsfb->base + LCDC_AS_BUF);
583 
584 	ctrl = AS_CTRL_AS_ENABLE | AS_CTRL_ALPHA(255);
585 
586 	switch (new_pstate->fb->format->format) {
587 	case DRM_FORMAT_XRGB4444:
588 		ctrl |= AS_CTRL_FORMAT_RGB444 | AS_CTRL_ALPHA_CTRL_OVERRIDE;
589 		break;
590 	case DRM_FORMAT_ARGB4444:
591 		ctrl |= AS_CTRL_FORMAT_ARGB4444 | AS_CTRL_ALPHA_CTRL_EMBEDDED;
592 		break;
593 	case DRM_FORMAT_XRGB1555:
594 		ctrl |= AS_CTRL_FORMAT_RGB555 | AS_CTRL_ALPHA_CTRL_OVERRIDE;
595 		break;
596 	case DRM_FORMAT_ARGB1555:
597 		ctrl |= AS_CTRL_FORMAT_ARGB1555 | AS_CTRL_ALPHA_CTRL_EMBEDDED;
598 		break;
599 	case DRM_FORMAT_RGB565:
600 		ctrl |= AS_CTRL_FORMAT_RGB565 | AS_CTRL_ALPHA_CTRL_OVERRIDE;
601 		break;
602 	case DRM_FORMAT_XRGB8888:
603 		ctrl |= AS_CTRL_FORMAT_RGB888 | AS_CTRL_ALPHA_CTRL_OVERRIDE;
604 		break;
605 	case DRM_FORMAT_ARGB8888:
606 		ctrl |= AS_CTRL_FORMAT_ARGB8888 | AS_CTRL_ALPHA_CTRL_EMBEDDED;
607 		break;
608 	}
609 
610 	writel(ctrl, mxsfb->base + LCDC_AS_CTRL);
611 }
612 
613 static bool mxsfb_format_mod_supported(struct drm_plane *plane,
614 				       uint32_t format,
615 				       uint64_t modifier)
616 {
617 	return modifier == DRM_FORMAT_MOD_LINEAR;
618 }
619 
620 static const struct drm_plane_helper_funcs mxsfb_plane_primary_helper_funcs = {
621 	.atomic_check = mxsfb_plane_atomic_check,
622 	.atomic_update = mxsfb_plane_primary_atomic_update,
623 };
624 
625 static const struct drm_plane_helper_funcs mxsfb_plane_overlay_helper_funcs = {
626 	.atomic_check = mxsfb_plane_atomic_check,
627 	.atomic_update = mxsfb_plane_overlay_atomic_update,
628 };
629 
630 static const struct drm_plane_funcs mxsfb_plane_funcs = {
631 	.format_mod_supported	= mxsfb_format_mod_supported,
632 	.update_plane		= drm_atomic_helper_update_plane,
633 	.disable_plane		= drm_atomic_helper_disable_plane,
634 	.destroy		= drm_plane_cleanup,
635 	.reset			= drm_atomic_helper_plane_reset,
636 	.atomic_duplicate_state	= drm_atomic_helper_plane_duplicate_state,
637 	.atomic_destroy_state	= drm_atomic_helper_plane_destroy_state,
638 };
639 
640 static const uint32_t mxsfb_primary_plane_formats[] = {
641 	DRM_FORMAT_RGB565,
642 	DRM_FORMAT_XRGB8888,
643 };
644 
645 static const uint32_t mxsfb_overlay_plane_formats[] = {
646 	DRM_FORMAT_XRGB4444,
647 	DRM_FORMAT_ARGB4444,
648 	DRM_FORMAT_XRGB1555,
649 	DRM_FORMAT_ARGB1555,
650 	DRM_FORMAT_RGB565,
651 	DRM_FORMAT_XRGB8888,
652 	DRM_FORMAT_ARGB8888,
653 };
654 
655 static const uint64_t mxsfb_modifiers[] = {
656 	DRM_FORMAT_MOD_LINEAR,
657 	DRM_FORMAT_MOD_INVALID
658 };
659 
660 /* -----------------------------------------------------------------------------
661  * Initialization
662  */
663 
664 int mxsfb_kms_init(struct mxsfb_drm_private *mxsfb)
665 {
666 	struct drm_encoder *encoder = &mxsfb->encoder;
667 	struct drm_crtc *crtc = &mxsfb->crtc;
668 	int ret;
669 
670 	drm_plane_helper_add(&mxsfb->planes.primary,
671 			     &mxsfb_plane_primary_helper_funcs);
672 	ret = drm_universal_plane_init(mxsfb->drm, &mxsfb->planes.primary, 1,
673 				       &mxsfb_plane_funcs,
674 				       mxsfb_primary_plane_formats,
675 				       ARRAY_SIZE(mxsfb_primary_plane_formats),
676 				       mxsfb_modifiers, DRM_PLANE_TYPE_PRIMARY,
677 				       NULL);
678 	if (ret)
679 		return ret;
680 
681 	if (mxsfb->devdata->has_overlay) {
682 		drm_plane_helper_add(&mxsfb->planes.overlay,
683 				     &mxsfb_plane_overlay_helper_funcs);
684 		ret = drm_universal_plane_init(mxsfb->drm,
685 					       &mxsfb->planes.overlay, 1,
686 					       &mxsfb_plane_funcs,
687 					       mxsfb_overlay_plane_formats,
688 					       ARRAY_SIZE(mxsfb_overlay_plane_formats),
689 					       mxsfb_modifiers, DRM_PLANE_TYPE_OVERLAY,
690 					       NULL);
691 		if (ret)
692 			return ret;
693 	}
694 
695 	drm_crtc_helper_add(crtc, &mxsfb_crtc_helper_funcs);
696 	if (mxsfb->devdata->has_crc32) {
697 		ret = drm_crtc_init_with_planes(mxsfb->drm, crtc,
698 						&mxsfb->planes.primary, NULL,
699 						&mxsfb_crtc_with_crc_funcs,
700 						NULL);
701 	} else {
702 		ret = drm_crtc_init_with_planes(mxsfb->drm, crtc,
703 						&mxsfb->planes.primary, NULL,
704 						&mxsfb_crtc_funcs, NULL);
705 	}
706 	if (ret)
707 		return ret;
708 
709 	encoder->possible_crtcs = drm_crtc_mask(crtc);
710 	return drm_encoder_init(mxsfb->drm, encoder, &mxsfb_encoder_funcs,
711 				DRM_MODE_ENCODER_NONE, NULL);
712 }
713