xref: /openbmc/linux/drivers/gpu/drm/stm/ltdc.c (revision a44e4f3a)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) STMicroelectronics SA 2017
4  *
5  * Authors: Philippe Cornu <philippe.cornu@st.com>
6  *          Yannick Fertre <yannick.fertre@st.com>
7  *          Fabien Dessenne <fabien.dessenne@st.com>
8  *          Mickael Reulier <mickael.reulier@st.com>
9  */
10 
11 #include <linux/clk.h>
12 #include <linux/component.h>
13 #include <linux/delay.h>
14 #include <linux/interrupt.h>
15 #include <linux/module.h>
16 #include <linux/of_address.h>
17 #include <linux/of_graph.h>
18 #include <linux/platform_device.h>
19 #include <linux/pm_runtime.h>
20 #include <linux/reset.h>
21 
22 #include <drm/drm_atomic.h>
23 #include <drm/drm_atomic_helper.h>
24 #include <drm/drm_bridge.h>
25 #include <drm/drm_device.h>
26 #include <drm/drm_fb_cma_helper.h>
27 #include <drm/drm_fourcc.h>
28 #include <drm/drm_gem_cma_helper.h>
29 #include <drm/drm_gem_framebuffer_helper.h>
30 #include <drm/drm_of.h>
31 #include <drm/drm_plane_helper.h>
32 #include <drm/drm_probe_helper.h>
33 #include <drm/drm_vblank.h>
34 
35 #include <video/videomode.h>
36 
37 #include "ltdc.h"
38 
39 #define NB_CRTC 1
40 #define CRTC_MASK GENMASK(NB_CRTC - 1, 0)
41 
42 #define MAX_IRQ 4
43 
44 #define MAX_ENDPOINTS 2
45 
46 #define HWVER_10200 0x010200
47 #define HWVER_10300 0x010300
48 #define HWVER_20101 0x020101
49 
50 /*
51  * The address of some registers depends on the HW version: such registers have
52  * an extra offset specified with reg_ofs.
53  */
54 #define REG_OFS_NONE	0
55 #define REG_OFS_4	4		/* Insertion of "Layer Conf. 2" reg */
56 #define REG_OFS		(ldev->caps.reg_ofs)
57 #define LAY_OFS		0x80		/* Register Offset between 2 layers */
58 
59 /* Global register offsets */
60 #define LTDC_IDR	0x0000		/* IDentification */
61 #define LTDC_LCR	0x0004		/* Layer Count */
62 #define LTDC_SSCR	0x0008		/* Synchronization Size Configuration */
63 #define LTDC_BPCR	0x000C		/* Back Porch Configuration */
64 #define LTDC_AWCR	0x0010		/* Active Width Configuration */
65 #define LTDC_TWCR	0x0014		/* Total Width Configuration */
66 #define LTDC_GCR	0x0018		/* Global Control */
67 #define LTDC_GC1R	0x001C		/* Global Configuration 1 */
68 #define LTDC_GC2R	0x0020		/* Global Configuration 2 */
69 #define LTDC_SRCR	0x0024		/* Shadow Reload Configuration */
70 #define LTDC_GACR	0x0028		/* GAmma Correction */
71 #define LTDC_BCCR	0x002C		/* Background Color Configuration */
72 #define LTDC_IER	0x0034		/* Interrupt Enable */
73 #define LTDC_ISR	0x0038		/* Interrupt Status */
74 #define LTDC_ICR	0x003C		/* Interrupt Clear */
75 #define LTDC_LIPCR	0x0040		/* Line Interrupt Position Conf. */
76 #define LTDC_CPSR	0x0044		/* Current Position Status */
77 #define LTDC_CDSR	0x0048		/* Current Display Status */
78 
79 /* Layer register offsets */
80 #define LTDC_L1LC1R	(0x80)		/* L1 Layer Configuration 1 */
81 #define LTDC_L1LC2R	(0x84)		/* L1 Layer Configuration 2 */
82 #define LTDC_L1CR	(0x84 + REG_OFS)/* L1 Control */
83 #define LTDC_L1WHPCR	(0x88 + REG_OFS)/* L1 Window Hor Position Config */
84 #define LTDC_L1WVPCR	(0x8C + REG_OFS)/* L1 Window Vert Position Config */
85 #define LTDC_L1CKCR	(0x90 + REG_OFS)/* L1 Color Keying Configuration */
86 #define LTDC_L1PFCR	(0x94 + REG_OFS)/* L1 Pixel Format Configuration */
87 #define LTDC_L1CACR	(0x98 + REG_OFS)/* L1 Constant Alpha Config */
88 #define LTDC_L1DCCR	(0x9C + REG_OFS)/* L1 Default Color Configuration */
89 #define LTDC_L1BFCR	(0xA0 + REG_OFS)/* L1 Blend Factors Configuration */
90 #define LTDC_L1FBBCR	(0xA4 + REG_OFS)/* L1 FrameBuffer Bus Control */
91 #define LTDC_L1AFBCR	(0xA8 + REG_OFS)/* L1 AuxFB Control */
92 #define LTDC_L1CFBAR	(0xAC + REG_OFS)/* L1 Color FrameBuffer Address */
93 #define LTDC_L1CFBLR	(0xB0 + REG_OFS)/* L1 Color FrameBuffer Length */
94 #define LTDC_L1CFBLNR	(0xB4 + REG_OFS)/* L1 Color FrameBuffer Line Nb */
95 #define LTDC_L1AFBAR	(0xB8 + REG_OFS)/* L1 AuxFB Address */
96 #define LTDC_L1AFBLR	(0xBC + REG_OFS)/* L1 AuxFB Length */
97 #define LTDC_L1AFBLNR	(0xC0 + REG_OFS)/* L1 AuxFB Line Number */
98 #define LTDC_L1CLUTWR	(0xC4 + REG_OFS)/* L1 CLUT Write */
99 #define LTDC_L1YS1R	(0xE0 + REG_OFS)/* L1 YCbCr Scale 1 */
100 #define LTDC_L1YS2R	(0xE4 + REG_OFS)/* L1 YCbCr Scale 2 */
101 
102 /* Bit definitions */
103 #define SSCR_VSH	GENMASK(10, 0)	/* Vertical Synchronization Height */
104 #define SSCR_HSW	GENMASK(27, 16)	/* Horizontal Synchronization Width */
105 
106 #define BPCR_AVBP	GENMASK(10, 0)	/* Accumulated Vertical Back Porch */
107 #define BPCR_AHBP	GENMASK(27, 16)	/* Accumulated Horizontal Back Porch */
108 
109 #define AWCR_AAH	GENMASK(10, 0)	/* Accumulated Active Height */
110 #define AWCR_AAW	GENMASK(27, 16)	/* Accumulated Active Width */
111 
112 #define TWCR_TOTALH	GENMASK(10, 0)	/* TOTAL Height */
113 #define TWCR_TOTALW	GENMASK(27, 16)	/* TOTAL Width */
114 
115 #define GCR_LTDCEN	BIT(0)		/* LTDC ENable */
116 #define GCR_DEN		BIT(16)		/* Dither ENable */
117 #define GCR_PCPOL	BIT(28)		/* Pixel Clock POLarity-Inverted */
118 #define GCR_DEPOL	BIT(29)		/* Data Enable POLarity-High */
119 #define GCR_VSPOL	BIT(30)		/* Vertical Synchro POLarity-High */
120 #define GCR_HSPOL	BIT(31)		/* Horizontal Synchro POLarity-High */
121 
122 #define GC1R_WBCH	GENMASK(3, 0)	/* Width of Blue CHannel output */
123 #define GC1R_WGCH	GENMASK(7, 4)	/* Width of Green Channel output */
124 #define GC1R_WRCH	GENMASK(11, 8)	/* Width of Red Channel output */
125 #define GC1R_PBEN	BIT(12)		/* Precise Blending ENable */
126 #define GC1R_DT		GENMASK(15, 14)	/* Dithering Technique */
127 #define GC1R_GCT	GENMASK(19, 17)	/* Gamma Correction Technique */
128 #define GC1R_SHREN	BIT(21)		/* SHadow Registers ENabled */
129 #define GC1R_BCP	BIT(22)		/* Background Colour Programmable */
130 #define GC1R_BBEN	BIT(23)		/* Background Blending ENabled */
131 #define GC1R_LNIP	BIT(24)		/* Line Number IRQ Position */
132 #define GC1R_TP		BIT(25)		/* Timing Programmable */
133 #define GC1R_IPP	BIT(26)		/* IRQ Polarity Programmable */
134 #define GC1R_SPP	BIT(27)		/* Sync Polarity Programmable */
135 #define GC1R_DWP	BIT(28)		/* Dither Width Programmable */
136 #define GC1R_STREN	BIT(29)		/* STatus Registers ENabled */
137 #define GC1R_BMEN	BIT(31)		/* Blind Mode ENabled */
138 
139 #define GC2R_EDCA	BIT(0)		/* External Display Control Ability  */
140 #define GC2R_STSAEN	BIT(1)		/* Slave Timing Sync Ability ENabled */
141 #define GC2R_DVAEN	BIT(2)		/* Dual-View Ability ENabled */
142 #define GC2R_DPAEN	BIT(3)		/* Dual-Port Ability ENabled */
143 #define GC2R_BW		GENMASK(6, 4)	/* Bus Width (log2 of nb of bytes) */
144 #define GC2R_EDCEN	BIT(7)		/* External Display Control ENabled */
145 
146 #define SRCR_IMR	BIT(0)		/* IMmediate Reload */
147 #define SRCR_VBR	BIT(1)		/* Vertical Blanking Reload */
148 
149 #define BCCR_BCBLACK	0x00		/* Background Color BLACK */
150 #define BCCR_BCBLUE	GENMASK(7, 0)	/* Background Color BLUE */
151 #define BCCR_BCGREEN	GENMASK(15, 8)	/* Background Color GREEN */
152 #define BCCR_BCRED	GENMASK(23, 16)	/* Background Color RED */
153 #define BCCR_BCWHITE	GENMASK(23, 0)	/* Background Color WHITE */
154 
155 #define IER_LIE		BIT(0)		/* Line Interrupt Enable */
156 #define IER_FUIE	BIT(1)		/* Fifo Underrun Interrupt Enable */
157 #define IER_TERRIE	BIT(2)		/* Transfer ERRor Interrupt Enable */
158 #define IER_RRIE	BIT(3)		/* Register Reload Interrupt enable */
159 
160 #define CPSR_CYPOS	GENMASK(15, 0)	/* Current Y position */
161 
162 #define ISR_LIF		BIT(0)		/* Line Interrupt Flag */
163 #define ISR_FUIF	BIT(1)		/* Fifo Underrun Interrupt Flag */
164 #define ISR_TERRIF	BIT(2)		/* Transfer ERRor Interrupt Flag */
165 #define ISR_RRIF	BIT(3)		/* Register Reload Interrupt Flag */
166 
167 #define LXCR_LEN	BIT(0)		/* Layer ENable */
168 #define LXCR_COLKEN	BIT(1)		/* Color Keying Enable */
169 #define LXCR_CLUTEN	BIT(4)		/* Color Look-Up Table ENable */
170 
171 #define LXWHPCR_WHSTPOS	GENMASK(11, 0)	/* Window Horizontal StarT POSition */
172 #define LXWHPCR_WHSPPOS	GENMASK(27, 16)	/* Window Horizontal StoP POSition */
173 
174 #define LXWVPCR_WVSTPOS	GENMASK(10, 0)	/* Window Vertical StarT POSition */
175 #define LXWVPCR_WVSPPOS	GENMASK(26, 16)	/* Window Vertical StoP POSition */
176 
177 #define LXPFCR_PF	GENMASK(2, 0)	/* Pixel Format */
178 
179 #define LXCACR_CONSTA	GENMASK(7, 0)	/* CONSTant Alpha */
180 
181 #define LXBFCR_BF2	GENMASK(2, 0)	/* Blending Factor 2 */
182 #define LXBFCR_BF1	GENMASK(10, 8)	/* Blending Factor 1 */
183 
184 #define LXCFBLR_CFBLL	GENMASK(12, 0)	/* Color Frame Buffer Line Length */
185 #define LXCFBLR_CFBP	GENMASK(28, 16)	/* Color Frame Buffer Pitch in bytes */
186 
187 #define LXCFBLNR_CFBLN	GENMASK(10, 0)	/* Color Frame Buffer Line Number */
188 
189 #define CLUT_SIZE	256
190 
191 #define CONSTA_MAX	0xFF		/* CONSTant Alpha MAX= 1.0 */
192 #define BF1_PAXCA	0x600		/* Pixel Alpha x Constant Alpha */
193 #define BF1_CA		0x400		/* Constant Alpha */
194 #define BF2_1PAXCA	0x007		/* 1 - (Pixel Alpha x Constant Alpha) */
195 #define BF2_1CA		0x005		/* 1 - Constant Alpha */
196 
197 #define NB_PF		8		/* Max nb of HW pixel format */
198 
199 enum ltdc_pix_fmt {
200 	PF_NONE,
201 	/* RGB formats */
202 	PF_ARGB8888,		/* ARGB [32 bits] */
203 	PF_RGBA8888,		/* RGBA [32 bits] */
204 	PF_RGB888,		/* RGB [24 bits] */
205 	PF_RGB565,		/* RGB [16 bits] */
206 	PF_ARGB1555,		/* ARGB A:1 bit RGB:15 bits [16 bits] */
207 	PF_ARGB4444,		/* ARGB A:4 bits R/G/B: 4 bits each [16 bits] */
208 	/* Indexed formats */
209 	PF_L8,			/* Indexed 8 bits [8 bits] */
210 	PF_AL44,		/* Alpha:4 bits + indexed 4 bits [8 bits] */
211 	PF_AL88			/* Alpha:8 bits + indexed 8 bits [16 bits] */
212 };
213 
214 /* The index gives the encoding of the pixel format for an HW version */
215 static const enum ltdc_pix_fmt ltdc_pix_fmt_a0[NB_PF] = {
216 	PF_ARGB8888,		/* 0x00 */
217 	PF_RGB888,		/* 0x01 */
218 	PF_RGB565,		/* 0x02 */
219 	PF_ARGB1555,		/* 0x03 */
220 	PF_ARGB4444,		/* 0x04 */
221 	PF_L8,			/* 0x05 */
222 	PF_AL44,		/* 0x06 */
223 	PF_AL88			/* 0x07 */
224 };
225 
226 static const enum ltdc_pix_fmt ltdc_pix_fmt_a1[NB_PF] = {
227 	PF_ARGB8888,		/* 0x00 */
228 	PF_RGB888,		/* 0x01 */
229 	PF_RGB565,		/* 0x02 */
230 	PF_RGBA8888,		/* 0x03 */
231 	PF_AL44,		/* 0x04 */
232 	PF_L8,			/* 0x05 */
233 	PF_ARGB1555,		/* 0x06 */
234 	PF_ARGB4444		/* 0x07 */
235 };
236 
237 static const u64 ltdc_format_modifiers[] = {
238 	DRM_FORMAT_MOD_LINEAR,
239 	DRM_FORMAT_MOD_INVALID
240 };
241 
242 static inline u32 reg_read(void __iomem *base, u32 reg)
243 {
244 	return readl_relaxed(base + reg);
245 }
246 
247 static inline void reg_write(void __iomem *base, u32 reg, u32 val)
248 {
249 	writel_relaxed(val, base + reg);
250 }
251 
252 static inline void reg_set(void __iomem *base, u32 reg, u32 mask)
253 {
254 	reg_write(base, reg, reg_read(base, reg) | mask);
255 }
256 
257 static inline void reg_clear(void __iomem *base, u32 reg, u32 mask)
258 {
259 	reg_write(base, reg, reg_read(base, reg) & ~mask);
260 }
261 
262 static inline void reg_update_bits(void __iomem *base, u32 reg, u32 mask,
263 				   u32 val)
264 {
265 	reg_write(base, reg, (reg_read(base, reg) & ~mask) | val);
266 }
267 
268 static inline struct ltdc_device *crtc_to_ltdc(struct drm_crtc *crtc)
269 {
270 	return (struct ltdc_device *)crtc->dev->dev_private;
271 }
272 
273 static inline struct ltdc_device *plane_to_ltdc(struct drm_plane *plane)
274 {
275 	return (struct ltdc_device *)plane->dev->dev_private;
276 }
277 
278 static inline struct ltdc_device *encoder_to_ltdc(struct drm_encoder *enc)
279 {
280 	return (struct ltdc_device *)enc->dev->dev_private;
281 }
282 
283 static inline enum ltdc_pix_fmt to_ltdc_pixelformat(u32 drm_fmt)
284 {
285 	enum ltdc_pix_fmt pf;
286 
287 	switch (drm_fmt) {
288 	case DRM_FORMAT_ARGB8888:
289 	case DRM_FORMAT_XRGB8888:
290 		pf = PF_ARGB8888;
291 		break;
292 	case DRM_FORMAT_RGBA8888:
293 	case DRM_FORMAT_RGBX8888:
294 		pf = PF_RGBA8888;
295 		break;
296 	case DRM_FORMAT_RGB888:
297 		pf = PF_RGB888;
298 		break;
299 	case DRM_FORMAT_RGB565:
300 		pf = PF_RGB565;
301 		break;
302 	case DRM_FORMAT_ARGB1555:
303 	case DRM_FORMAT_XRGB1555:
304 		pf = PF_ARGB1555;
305 		break;
306 	case DRM_FORMAT_ARGB4444:
307 	case DRM_FORMAT_XRGB4444:
308 		pf = PF_ARGB4444;
309 		break;
310 	case DRM_FORMAT_C8:
311 		pf = PF_L8;
312 		break;
313 	default:
314 		pf = PF_NONE;
315 		break;
316 		/* Note: There are no DRM_FORMAT for AL44 and AL88 */
317 	}
318 
319 	return pf;
320 }
321 
322 static inline u32 to_drm_pixelformat(enum ltdc_pix_fmt pf)
323 {
324 	switch (pf) {
325 	case PF_ARGB8888:
326 		return DRM_FORMAT_ARGB8888;
327 	case PF_RGBA8888:
328 		return DRM_FORMAT_RGBA8888;
329 	case PF_RGB888:
330 		return DRM_FORMAT_RGB888;
331 	case PF_RGB565:
332 		return DRM_FORMAT_RGB565;
333 	case PF_ARGB1555:
334 		return DRM_FORMAT_ARGB1555;
335 	case PF_ARGB4444:
336 		return DRM_FORMAT_ARGB4444;
337 	case PF_L8:
338 		return DRM_FORMAT_C8;
339 	case PF_AL44:		/* No DRM support */
340 	case PF_AL88:		/* No DRM support */
341 	case PF_NONE:
342 	default:
343 		return 0;
344 	}
345 }
346 
347 static inline u32 get_pixelformat_without_alpha(u32 drm)
348 {
349 	switch (drm) {
350 	case DRM_FORMAT_ARGB4444:
351 		return DRM_FORMAT_XRGB4444;
352 	case DRM_FORMAT_RGBA4444:
353 		return DRM_FORMAT_RGBX4444;
354 	case DRM_FORMAT_ARGB1555:
355 		return DRM_FORMAT_XRGB1555;
356 	case DRM_FORMAT_RGBA5551:
357 		return DRM_FORMAT_RGBX5551;
358 	case DRM_FORMAT_ARGB8888:
359 		return DRM_FORMAT_XRGB8888;
360 	case DRM_FORMAT_RGBA8888:
361 		return DRM_FORMAT_RGBX8888;
362 	default:
363 		return 0;
364 	}
365 }
366 
367 static irqreturn_t ltdc_irq_thread(int irq, void *arg)
368 {
369 	struct drm_device *ddev = arg;
370 	struct ltdc_device *ldev = ddev->dev_private;
371 	struct drm_crtc *crtc = drm_crtc_from_index(ddev, 0);
372 
373 	/* Line IRQ : trigger the vblank event */
374 	if (ldev->irq_status & ISR_LIF)
375 		drm_crtc_handle_vblank(crtc);
376 
377 	/* Save FIFO Underrun & Transfer Error status */
378 	mutex_lock(&ldev->err_lock);
379 	if (ldev->irq_status & ISR_FUIF)
380 		ldev->error_status |= ISR_FUIF;
381 	if (ldev->irq_status & ISR_TERRIF)
382 		ldev->error_status |= ISR_TERRIF;
383 	mutex_unlock(&ldev->err_lock);
384 
385 	return IRQ_HANDLED;
386 }
387 
388 static irqreturn_t ltdc_irq(int irq, void *arg)
389 {
390 	struct drm_device *ddev = arg;
391 	struct ltdc_device *ldev = ddev->dev_private;
392 
393 	/* Read & Clear the interrupt status */
394 	ldev->irq_status = reg_read(ldev->regs, LTDC_ISR);
395 	reg_write(ldev->regs, LTDC_ICR, ldev->irq_status);
396 
397 	return IRQ_WAKE_THREAD;
398 }
399 
400 /*
401  * DRM_CRTC
402  */
403 
404 static void ltdc_crtc_update_clut(struct drm_crtc *crtc)
405 {
406 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
407 	struct drm_color_lut *lut;
408 	u32 val;
409 	int i;
410 
411 	if (!crtc->state->color_mgmt_changed || !crtc->state->gamma_lut)
412 		return;
413 
414 	lut = (struct drm_color_lut *)crtc->state->gamma_lut->data;
415 
416 	for (i = 0; i < CLUT_SIZE; i++, lut++) {
417 		val = ((lut->red << 8) & 0xff0000) | (lut->green & 0xff00) |
418 			(lut->blue >> 8) | (i << 24);
419 		reg_write(ldev->regs, LTDC_L1CLUTWR, val);
420 	}
421 }
422 
423 static void ltdc_crtc_atomic_enable(struct drm_crtc *crtc,
424 				    struct drm_crtc_state *old_state)
425 {
426 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
427 
428 	DRM_DEBUG_DRIVER("\n");
429 
430 	/* Sets the background color value */
431 	reg_write(ldev->regs, LTDC_BCCR, BCCR_BCBLACK);
432 
433 	/* Enable IRQ */
434 	reg_set(ldev->regs, LTDC_IER, IER_RRIE | IER_FUIE | IER_TERRIE);
435 
436 	/* Commit shadow registers = update planes at next vblank */
437 	reg_set(ldev->regs, LTDC_SRCR, SRCR_VBR);
438 
439 	/* Enable LTDC */
440 	reg_set(ldev->regs, LTDC_GCR, GCR_LTDCEN);
441 
442 	drm_crtc_vblank_on(crtc);
443 }
444 
445 static void ltdc_crtc_atomic_disable(struct drm_crtc *crtc,
446 				     struct drm_crtc_state *old_state)
447 {
448 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
449 	struct drm_device *ddev = crtc->dev;
450 
451 	DRM_DEBUG_DRIVER("\n");
452 
453 	drm_crtc_vblank_off(crtc);
454 
455 	/* disable LTDC */
456 	reg_clear(ldev->regs, LTDC_GCR, GCR_LTDCEN);
457 
458 	/* disable IRQ */
459 	reg_clear(ldev->regs, LTDC_IER, IER_RRIE | IER_FUIE | IER_TERRIE);
460 
461 	/* immediately commit disable of layers before switching off LTDC */
462 	reg_set(ldev->regs, LTDC_SRCR, SRCR_IMR);
463 
464 	pm_runtime_put_sync(ddev->dev);
465 }
466 
467 #define CLK_TOLERANCE_HZ 50
468 
469 static enum drm_mode_status
470 ltdc_crtc_mode_valid(struct drm_crtc *crtc,
471 		     const struct drm_display_mode *mode)
472 {
473 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
474 	int target = mode->clock * 1000;
475 	int target_min = target - CLK_TOLERANCE_HZ;
476 	int target_max = target + CLK_TOLERANCE_HZ;
477 	int result;
478 
479 	result = clk_round_rate(ldev->pixel_clk, target);
480 
481 	DRM_DEBUG_DRIVER("clk rate target %d, available %d\n", target, result);
482 
483 	/* Filter modes according to the max frequency supported by the pads */
484 	if (result > ldev->caps.pad_max_freq_hz)
485 		return MODE_CLOCK_HIGH;
486 
487 	/*
488 	 * Accept all "preferred" modes:
489 	 * - this is important for panels because panel clock tolerances are
490 	 *   bigger than hdmi ones and there is no reason to not accept them
491 	 *   (the fps may vary a little but it is not a problem).
492 	 * - the hdmi preferred mode will be accepted too, but userland will
493 	 *   be able to use others hdmi "valid" modes if necessary.
494 	 */
495 	if (mode->type & DRM_MODE_TYPE_PREFERRED)
496 		return MODE_OK;
497 
498 	/*
499 	 * Filter modes according to the clock value, particularly useful for
500 	 * hdmi modes that require precise pixel clocks.
501 	 */
502 	if (result < target_min || result > target_max)
503 		return MODE_CLOCK_RANGE;
504 
505 	return MODE_OK;
506 }
507 
508 static bool ltdc_crtc_mode_fixup(struct drm_crtc *crtc,
509 				 const struct drm_display_mode *mode,
510 				 struct drm_display_mode *adjusted_mode)
511 {
512 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
513 	struct drm_device *ddev = crtc->dev;
514 	int rate = mode->clock * 1000;
515 	bool runtime_active;
516 	int ret;
517 
518 	runtime_active = pm_runtime_active(ddev->dev);
519 
520 	if (runtime_active)
521 		pm_runtime_put_sync(ddev->dev);
522 
523 	if (clk_set_rate(ldev->pixel_clk, rate) < 0) {
524 		DRM_ERROR("Cannot set rate (%dHz) for pixel clk\n", rate);
525 		return false;
526 	}
527 
528 	adjusted_mode->clock = clk_get_rate(ldev->pixel_clk) / 1000;
529 
530 	if (runtime_active) {
531 		ret = pm_runtime_get_sync(ddev->dev);
532 		if (ret) {
533 			DRM_ERROR("Failed to fixup mode, cannot get sync\n");
534 			return false;
535 		}
536 	}
537 
538 	DRM_DEBUG_DRIVER("requested clock %dkHz, adjusted clock %dkHz\n",
539 			 mode->clock, adjusted_mode->clock);
540 
541 	return true;
542 }
543 
544 static void ltdc_crtc_mode_set_nofb(struct drm_crtc *crtc)
545 {
546 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
547 	struct drm_device *ddev = crtc->dev;
548 	struct drm_display_mode *mode = &crtc->state->adjusted_mode;
549 	struct videomode vm;
550 	u32 hsync, vsync, accum_hbp, accum_vbp, accum_act_w, accum_act_h;
551 	u32 total_width, total_height;
552 	u32 val;
553 	int ret;
554 
555 	if (!pm_runtime_active(ddev->dev)) {
556 		ret = pm_runtime_get_sync(ddev->dev);
557 		if (ret) {
558 			DRM_ERROR("Failed to set mode, cannot get sync\n");
559 			return;
560 		}
561 	}
562 
563 	drm_display_mode_to_videomode(mode, &vm);
564 
565 	DRM_DEBUG_DRIVER("CRTC:%d mode:%s\n", crtc->base.id, mode->name);
566 	DRM_DEBUG_DRIVER("Video mode: %dx%d", vm.hactive, vm.vactive);
567 	DRM_DEBUG_DRIVER(" hfp %d hbp %d hsl %d vfp %d vbp %d vsl %d\n",
568 			 vm.hfront_porch, vm.hback_porch, vm.hsync_len,
569 			 vm.vfront_porch, vm.vback_porch, vm.vsync_len);
570 
571 	/* Convert video timings to ltdc timings */
572 	hsync = vm.hsync_len - 1;
573 	vsync = vm.vsync_len - 1;
574 	accum_hbp = hsync + vm.hback_porch;
575 	accum_vbp = vsync + vm.vback_porch;
576 	accum_act_w = accum_hbp + vm.hactive;
577 	accum_act_h = accum_vbp + vm.vactive;
578 	total_width = accum_act_w + vm.hfront_porch;
579 	total_height = accum_act_h + vm.vfront_porch;
580 
581 	/* Configures the HS, VS, DE and PC polarities. Default Active Low */
582 	val = 0;
583 
584 	if (vm.flags & DISPLAY_FLAGS_HSYNC_HIGH)
585 		val |= GCR_HSPOL;
586 
587 	if (vm.flags & DISPLAY_FLAGS_VSYNC_HIGH)
588 		val |= GCR_VSPOL;
589 
590 	if (vm.flags & DISPLAY_FLAGS_DE_LOW)
591 		val |= GCR_DEPOL;
592 
593 	if (vm.flags & DISPLAY_FLAGS_PIXDATA_NEGEDGE)
594 		val |= GCR_PCPOL;
595 
596 	reg_update_bits(ldev->regs, LTDC_GCR,
597 			GCR_HSPOL | GCR_VSPOL | GCR_DEPOL | GCR_PCPOL, val);
598 
599 	/* Set Synchronization size */
600 	val = (hsync << 16) | vsync;
601 	reg_update_bits(ldev->regs, LTDC_SSCR, SSCR_VSH | SSCR_HSW, val);
602 
603 	/* Set Accumulated Back porch */
604 	val = (accum_hbp << 16) | accum_vbp;
605 	reg_update_bits(ldev->regs, LTDC_BPCR, BPCR_AVBP | BPCR_AHBP, val);
606 
607 	/* Set Accumulated Active Width */
608 	val = (accum_act_w << 16) | accum_act_h;
609 	reg_update_bits(ldev->regs, LTDC_AWCR, AWCR_AAW | AWCR_AAH, val);
610 
611 	/* Set total width & height */
612 	val = (total_width << 16) | total_height;
613 	reg_update_bits(ldev->regs, LTDC_TWCR, TWCR_TOTALH | TWCR_TOTALW, val);
614 
615 	reg_write(ldev->regs, LTDC_LIPCR, (accum_act_h + 1));
616 }
617 
618 static void ltdc_crtc_atomic_flush(struct drm_crtc *crtc,
619 				   struct drm_crtc_state *old_crtc_state)
620 {
621 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
622 	struct drm_device *ddev = crtc->dev;
623 	struct drm_pending_vblank_event *event = crtc->state->event;
624 
625 	DRM_DEBUG_ATOMIC("\n");
626 
627 	ltdc_crtc_update_clut(crtc);
628 
629 	/* Commit shadow registers = update planes at next vblank */
630 	reg_set(ldev->regs, LTDC_SRCR, SRCR_VBR);
631 
632 	if (event) {
633 		crtc->state->event = NULL;
634 
635 		spin_lock_irq(&ddev->event_lock);
636 		if (drm_crtc_vblank_get(crtc) == 0)
637 			drm_crtc_arm_vblank_event(crtc, event);
638 		else
639 			drm_crtc_send_vblank_event(crtc, event);
640 		spin_unlock_irq(&ddev->event_lock);
641 	}
642 }
643 
644 static const struct drm_crtc_helper_funcs ltdc_crtc_helper_funcs = {
645 	.mode_valid = ltdc_crtc_mode_valid,
646 	.mode_fixup = ltdc_crtc_mode_fixup,
647 	.mode_set_nofb = ltdc_crtc_mode_set_nofb,
648 	.atomic_flush = ltdc_crtc_atomic_flush,
649 	.atomic_enable = ltdc_crtc_atomic_enable,
650 	.atomic_disable = ltdc_crtc_atomic_disable,
651 };
652 
653 static int ltdc_crtc_enable_vblank(struct drm_crtc *crtc)
654 {
655 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
656 
657 	DRM_DEBUG_DRIVER("\n");
658 	reg_set(ldev->regs, LTDC_IER, IER_LIE);
659 
660 	return 0;
661 }
662 
663 static void ltdc_crtc_disable_vblank(struct drm_crtc *crtc)
664 {
665 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
666 
667 	DRM_DEBUG_DRIVER("\n");
668 	reg_clear(ldev->regs, LTDC_IER, IER_LIE);
669 }
670 
671 bool ltdc_crtc_scanoutpos(struct drm_device *ddev, unsigned int pipe,
672 			  bool in_vblank_irq, int *vpos, int *hpos,
673 			  ktime_t *stime, ktime_t *etime,
674 			  const struct drm_display_mode *mode)
675 {
676 	struct ltdc_device *ldev = ddev->dev_private;
677 	int line, vactive_start, vactive_end, vtotal;
678 
679 	if (stime)
680 		*stime = ktime_get();
681 
682 	/* The active area starts after vsync + front porch and ends
683 	 * at vsync + front porc + display size.
684 	 * The total height also include back porch.
685 	 * We have 3 possible cases to handle:
686 	 * - line < vactive_start: vpos = line - vactive_start and will be
687 	 * negative
688 	 * - vactive_start < line < vactive_end: vpos = line - vactive_start
689 	 * and will be positive
690 	 * - line > vactive_end: vpos = line - vtotal - vactive_start
691 	 * and will negative
692 	 *
693 	 * Computation for the two first cases are identical so we can
694 	 * simplify the code and only test if line > vactive_end
695 	 */
696 	if (pm_runtime_active(ddev->dev)) {
697 		line = reg_read(ldev->regs, LTDC_CPSR) & CPSR_CYPOS;
698 		vactive_start = reg_read(ldev->regs, LTDC_BPCR) & BPCR_AVBP;
699 		vactive_end = reg_read(ldev->regs, LTDC_AWCR) & AWCR_AAH;
700 		vtotal = reg_read(ldev->regs, LTDC_TWCR) & TWCR_TOTALH;
701 
702 		if (line > vactive_end)
703 			*vpos = line - vtotal - vactive_start;
704 		else
705 			*vpos = line - vactive_start;
706 	} else {
707 		*vpos = 0;
708 	}
709 
710 	*hpos = 0;
711 
712 	if (etime)
713 		*etime = ktime_get();
714 
715 	return true;
716 }
717 
718 static const struct drm_crtc_funcs ltdc_crtc_funcs = {
719 	.destroy = drm_crtc_cleanup,
720 	.set_config = drm_atomic_helper_set_config,
721 	.page_flip = drm_atomic_helper_page_flip,
722 	.reset = drm_atomic_helper_crtc_reset,
723 	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
724 	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
725 	.enable_vblank = ltdc_crtc_enable_vblank,
726 	.disable_vblank = ltdc_crtc_disable_vblank,
727 	.gamma_set = drm_atomic_helper_legacy_gamma_set,
728 };
729 
730 /*
731  * DRM_PLANE
732  */
733 
734 static int ltdc_plane_atomic_check(struct drm_plane *plane,
735 				   struct drm_plane_state *state)
736 {
737 	struct drm_framebuffer *fb = state->fb;
738 	u32 src_w, src_h;
739 
740 	DRM_DEBUG_DRIVER("\n");
741 
742 	if (!fb)
743 		return 0;
744 
745 	/* convert src_ from 16:16 format */
746 	src_w = state->src_w >> 16;
747 	src_h = state->src_h >> 16;
748 
749 	/* Reject scaling */
750 	if (src_w != state->crtc_w || src_h != state->crtc_h) {
751 		DRM_ERROR("Scaling is not supported");
752 		return -EINVAL;
753 	}
754 
755 	return 0;
756 }
757 
758 static void ltdc_plane_atomic_update(struct drm_plane *plane,
759 				     struct drm_plane_state *oldstate)
760 {
761 	struct ltdc_device *ldev = plane_to_ltdc(plane);
762 	struct drm_plane_state *state = plane->state;
763 	struct drm_framebuffer *fb = state->fb;
764 	u32 lofs = plane->index * LAY_OFS;
765 	u32 x0 = state->crtc_x;
766 	u32 x1 = state->crtc_x + state->crtc_w - 1;
767 	u32 y0 = state->crtc_y;
768 	u32 y1 = state->crtc_y + state->crtc_h - 1;
769 	u32 src_x, src_y, src_w, src_h;
770 	u32 val, pitch_in_bytes, line_length, paddr, ahbp, avbp, bpcr;
771 	enum ltdc_pix_fmt pf;
772 
773 	if (!state->crtc || !fb) {
774 		DRM_DEBUG_DRIVER("fb or crtc NULL");
775 		return;
776 	}
777 
778 	/* convert src_ from 16:16 format */
779 	src_x = state->src_x >> 16;
780 	src_y = state->src_y >> 16;
781 	src_w = state->src_w >> 16;
782 	src_h = state->src_h >> 16;
783 
784 	DRM_DEBUG_DRIVER("plane:%d fb:%d (%dx%d)@(%d,%d) -> (%dx%d)@(%d,%d)\n",
785 			 plane->base.id, fb->base.id,
786 			 src_w, src_h, src_x, src_y,
787 			 state->crtc_w, state->crtc_h,
788 			 state->crtc_x, state->crtc_y);
789 
790 	bpcr = reg_read(ldev->regs, LTDC_BPCR);
791 	ahbp = (bpcr & BPCR_AHBP) >> 16;
792 	avbp = bpcr & BPCR_AVBP;
793 
794 	/* Configures the horizontal start and stop position */
795 	val = ((x1 + 1 + ahbp) << 16) + (x0 + 1 + ahbp);
796 	reg_update_bits(ldev->regs, LTDC_L1WHPCR + lofs,
797 			LXWHPCR_WHSTPOS | LXWHPCR_WHSPPOS, val);
798 
799 	/* Configures the vertical start and stop position */
800 	val = ((y1 + 1 + avbp) << 16) + (y0 + 1 + avbp);
801 	reg_update_bits(ldev->regs, LTDC_L1WVPCR + lofs,
802 			LXWVPCR_WVSTPOS | LXWVPCR_WVSPPOS, val);
803 
804 	/* Specifies the pixel format */
805 	pf = to_ltdc_pixelformat(fb->format->format);
806 	for (val = 0; val < NB_PF; val++)
807 		if (ldev->caps.pix_fmt_hw[val] == pf)
808 			break;
809 
810 	if (val == NB_PF) {
811 		DRM_ERROR("Pixel format %.4s not supported\n",
812 			  (char *)&fb->format->format);
813 		val = 0;	/* set by default ARGB 32 bits */
814 	}
815 	reg_update_bits(ldev->regs, LTDC_L1PFCR + lofs, LXPFCR_PF, val);
816 
817 	/* Configures the color frame buffer pitch in bytes & line length */
818 	pitch_in_bytes = fb->pitches[0];
819 	line_length = fb->format->cpp[0] *
820 		      (x1 - x0 + 1) + (ldev->caps.bus_width >> 3) - 1;
821 	val = ((pitch_in_bytes << 16) | line_length);
822 	reg_update_bits(ldev->regs, LTDC_L1CFBLR + lofs,
823 			LXCFBLR_CFBLL | LXCFBLR_CFBP, val);
824 
825 	/* Specifies the constant alpha value */
826 	val = CONSTA_MAX;
827 	reg_update_bits(ldev->regs, LTDC_L1CACR + lofs, LXCACR_CONSTA, val);
828 
829 	/* Specifies the blending factors */
830 	val = BF1_PAXCA | BF2_1PAXCA;
831 	if (!fb->format->has_alpha)
832 		val = BF1_CA | BF2_1CA;
833 
834 	/* Manage hw-specific capabilities */
835 	if (ldev->caps.non_alpha_only_l1 &&
836 	    plane->type != DRM_PLANE_TYPE_PRIMARY)
837 		val = BF1_PAXCA | BF2_1PAXCA;
838 
839 	reg_update_bits(ldev->regs, LTDC_L1BFCR + lofs,
840 			LXBFCR_BF2 | LXBFCR_BF1, val);
841 
842 	/* Configures the frame buffer line number */
843 	val = y1 - y0 + 1;
844 	reg_update_bits(ldev->regs, LTDC_L1CFBLNR + lofs, LXCFBLNR_CFBLN, val);
845 
846 	/* Sets the FB address */
847 	paddr = (u32)drm_fb_cma_get_gem_addr(fb, state, 0);
848 
849 	DRM_DEBUG_DRIVER("fb: phys 0x%08x", paddr);
850 	reg_write(ldev->regs, LTDC_L1CFBAR + lofs, paddr);
851 
852 	/* Enable layer and CLUT if needed */
853 	val = fb->format->format == DRM_FORMAT_C8 ? LXCR_CLUTEN : 0;
854 	val |= LXCR_LEN;
855 	reg_update_bits(ldev->regs, LTDC_L1CR + lofs,
856 			LXCR_LEN | LXCR_CLUTEN, val);
857 
858 	ldev->plane_fpsi[plane->index].counter++;
859 
860 	mutex_lock(&ldev->err_lock);
861 	if (ldev->error_status & ISR_FUIF) {
862 		DRM_WARN("ltdc fifo underrun: please verify display mode\n");
863 		ldev->error_status &= ~ISR_FUIF;
864 	}
865 	if (ldev->error_status & ISR_TERRIF) {
866 		DRM_WARN("ltdc transfer error\n");
867 		ldev->error_status &= ~ISR_TERRIF;
868 	}
869 	mutex_unlock(&ldev->err_lock);
870 }
871 
872 static void ltdc_plane_atomic_disable(struct drm_plane *plane,
873 				      struct drm_plane_state *oldstate)
874 {
875 	struct ltdc_device *ldev = plane_to_ltdc(plane);
876 	u32 lofs = plane->index * LAY_OFS;
877 
878 	/* disable layer */
879 	reg_clear(ldev->regs, LTDC_L1CR + lofs, LXCR_LEN);
880 
881 	DRM_DEBUG_DRIVER("CRTC:%d plane:%d\n",
882 			 oldstate->crtc->base.id, plane->base.id);
883 }
884 
885 static void ltdc_plane_atomic_print_state(struct drm_printer *p,
886 					  const struct drm_plane_state *state)
887 {
888 	struct drm_plane *plane = state->plane;
889 	struct ltdc_device *ldev = plane_to_ltdc(plane);
890 	struct fps_info *fpsi = &ldev->plane_fpsi[plane->index];
891 	int ms_since_last;
892 	ktime_t now;
893 
894 	now = ktime_get();
895 	ms_since_last = ktime_to_ms(ktime_sub(now, fpsi->last_timestamp));
896 
897 	drm_printf(p, "\tuser_updates=%dfps\n",
898 		   DIV_ROUND_CLOSEST(fpsi->counter * 1000, ms_since_last));
899 
900 	fpsi->last_timestamp = now;
901 	fpsi->counter = 0;
902 }
903 
904 static bool ltdc_plane_format_mod_supported(struct drm_plane *plane,
905 					    u32 format,
906 					    u64 modifier)
907 {
908 	if (modifier == DRM_FORMAT_MOD_LINEAR)
909 		return true;
910 
911 	return false;
912 }
913 
914 static const struct drm_plane_funcs ltdc_plane_funcs = {
915 	.update_plane = drm_atomic_helper_update_plane,
916 	.disable_plane = drm_atomic_helper_disable_plane,
917 	.destroy = drm_plane_cleanup,
918 	.reset = drm_atomic_helper_plane_reset,
919 	.atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
920 	.atomic_destroy_state = drm_atomic_helper_plane_destroy_state,
921 	.atomic_print_state = ltdc_plane_atomic_print_state,
922 	.format_mod_supported = ltdc_plane_format_mod_supported,
923 };
924 
925 static const struct drm_plane_helper_funcs ltdc_plane_helper_funcs = {
926 	.prepare_fb = drm_gem_fb_prepare_fb,
927 	.atomic_check = ltdc_plane_atomic_check,
928 	.atomic_update = ltdc_plane_atomic_update,
929 	.atomic_disable = ltdc_plane_atomic_disable,
930 };
931 
932 static struct drm_plane *ltdc_plane_create(struct drm_device *ddev,
933 					   enum drm_plane_type type)
934 {
935 	unsigned long possible_crtcs = CRTC_MASK;
936 	struct ltdc_device *ldev = ddev->dev_private;
937 	struct device *dev = ddev->dev;
938 	struct drm_plane *plane;
939 	unsigned int i, nb_fmt = 0;
940 	u32 formats[NB_PF * 2];
941 	u32 drm_fmt, drm_fmt_no_alpha;
942 	const u64 *modifiers = ltdc_format_modifiers;
943 	int ret;
944 
945 	/* Get supported pixel formats */
946 	for (i = 0; i < NB_PF; i++) {
947 		drm_fmt = to_drm_pixelformat(ldev->caps.pix_fmt_hw[i]);
948 		if (!drm_fmt)
949 			continue;
950 		formats[nb_fmt++] = drm_fmt;
951 
952 		/* Add the no-alpha related format if any & supported */
953 		drm_fmt_no_alpha = get_pixelformat_without_alpha(drm_fmt);
954 		if (!drm_fmt_no_alpha)
955 			continue;
956 
957 		/* Manage hw-specific capabilities */
958 		if (ldev->caps.non_alpha_only_l1 &&
959 		    type != DRM_PLANE_TYPE_PRIMARY)
960 			continue;
961 
962 		formats[nb_fmt++] = drm_fmt_no_alpha;
963 	}
964 
965 	plane = devm_kzalloc(dev, sizeof(*plane), GFP_KERNEL);
966 	if (!plane)
967 		return NULL;
968 
969 	ret = drm_universal_plane_init(ddev, plane, possible_crtcs,
970 				       &ltdc_plane_funcs, formats, nb_fmt,
971 				       modifiers, type, NULL);
972 	if (ret < 0)
973 		return NULL;
974 
975 	drm_plane_helper_add(plane, &ltdc_plane_helper_funcs);
976 
977 	DRM_DEBUG_DRIVER("plane:%d created\n", plane->base.id);
978 
979 	return plane;
980 }
981 
982 static void ltdc_plane_destroy_all(struct drm_device *ddev)
983 {
984 	struct drm_plane *plane, *plane_temp;
985 
986 	list_for_each_entry_safe(plane, plane_temp,
987 				 &ddev->mode_config.plane_list, head)
988 		drm_plane_cleanup(plane);
989 }
990 
991 static int ltdc_crtc_init(struct drm_device *ddev, struct drm_crtc *crtc)
992 {
993 	struct ltdc_device *ldev = ddev->dev_private;
994 	struct drm_plane *primary, *overlay;
995 	unsigned int i;
996 	int ret;
997 
998 	primary = ltdc_plane_create(ddev, DRM_PLANE_TYPE_PRIMARY);
999 	if (!primary) {
1000 		DRM_ERROR("Can not create primary plane\n");
1001 		return -EINVAL;
1002 	}
1003 
1004 	ret = drm_crtc_init_with_planes(ddev, crtc, primary, NULL,
1005 					&ltdc_crtc_funcs, NULL);
1006 	if (ret) {
1007 		DRM_ERROR("Can not initialize CRTC\n");
1008 		goto cleanup;
1009 	}
1010 
1011 	drm_crtc_helper_add(crtc, &ltdc_crtc_helper_funcs);
1012 
1013 	drm_mode_crtc_set_gamma_size(crtc, CLUT_SIZE);
1014 	drm_crtc_enable_color_mgmt(crtc, 0, false, CLUT_SIZE);
1015 
1016 	DRM_DEBUG_DRIVER("CRTC:%d created\n", crtc->base.id);
1017 
1018 	/* Add planes. Note : the first layer is used by primary plane */
1019 	for (i = 1; i < ldev->caps.nb_layers; i++) {
1020 		overlay = ltdc_plane_create(ddev, DRM_PLANE_TYPE_OVERLAY);
1021 		if (!overlay) {
1022 			ret = -ENOMEM;
1023 			DRM_ERROR("Can not create overlay plane %d\n", i);
1024 			goto cleanup;
1025 		}
1026 	}
1027 
1028 	return 0;
1029 
1030 cleanup:
1031 	ltdc_plane_destroy_all(ddev);
1032 	return ret;
1033 }
1034 
1035 /*
1036  * DRM_ENCODER
1037  */
1038 
1039 static const struct drm_encoder_funcs ltdc_encoder_funcs = {
1040 	.destroy = drm_encoder_cleanup,
1041 };
1042 
1043 static int ltdc_encoder_init(struct drm_device *ddev, struct drm_bridge *bridge)
1044 {
1045 	struct drm_encoder *encoder;
1046 	int ret;
1047 
1048 	encoder = devm_kzalloc(ddev->dev, sizeof(*encoder), GFP_KERNEL);
1049 	if (!encoder)
1050 		return -ENOMEM;
1051 
1052 	encoder->possible_crtcs = CRTC_MASK;
1053 	encoder->possible_clones = 0;	/* No cloning support */
1054 
1055 	drm_encoder_init(ddev, encoder, &ltdc_encoder_funcs,
1056 			 DRM_MODE_ENCODER_DPI, NULL);
1057 
1058 	ret = drm_bridge_attach(encoder, bridge, NULL);
1059 	if (ret) {
1060 		drm_encoder_cleanup(encoder);
1061 		return -EINVAL;
1062 	}
1063 
1064 	DRM_DEBUG_DRIVER("Bridge encoder:%d created\n", encoder->base.id);
1065 
1066 	return 0;
1067 }
1068 
1069 static int ltdc_get_caps(struct drm_device *ddev)
1070 {
1071 	struct ltdc_device *ldev = ddev->dev_private;
1072 	u32 bus_width_log2, lcr, gc2r;
1073 
1074 	/*
1075 	 * at least 1 layer must be managed & the number of layers
1076 	 * must not exceed LTDC_MAX_LAYER
1077 	 */
1078 	lcr = reg_read(ldev->regs, LTDC_LCR);
1079 
1080 	ldev->caps.nb_layers = clamp((int)lcr, 1, LTDC_MAX_LAYER);
1081 
1082 	/* set data bus width */
1083 	gc2r = reg_read(ldev->regs, LTDC_GC2R);
1084 	bus_width_log2 = (gc2r & GC2R_BW) >> 4;
1085 	ldev->caps.bus_width = 8 << bus_width_log2;
1086 	ldev->caps.hw_version = reg_read(ldev->regs, LTDC_IDR);
1087 
1088 	switch (ldev->caps.hw_version) {
1089 	case HWVER_10200:
1090 	case HWVER_10300:
1091 		ldev->caps.reg_ofs = REG_OFS_NONE;
1092 		ldev->caps.pix_fmt_hw = ltdc_pix_fmt_a0;
1093 		/*
1094 		 * Hw older versions support non-alpha color formats derived
1095 		 * from native alpha color formats only on the primary layer.
1096 		 * For instance, RG16 native format without alpha works fine
1097 		 * on 2nd layer but XR24 (derived color format from AR24)
1098 		 * does not work on 2nd layer.
1099 		 */
1100 		ldev->caps.non_alpha_only_l1 = true;
1101 		ldev->caps.pad_max_freq_hz = 90000000;
1102 		if (ldev->caps.hw_version == HWVER_10200)
1103 			ldev->caps.pad_max_freq_hz = 65000000;
1104 		break;
1105 	case HWVER_20101:
1106 		ldev->caps.reg_ofs = REG_OFS_4;
1107 		ldev->caps.pix_fmt_hw = ltdc_pix_fmt_a1;
1108 		ldev->caps.non_alpha_only_l1 = false;
1109 		ldev->caps.pad_max_freq_hz = 150000000;
1110 		break;
1111 	default:
1112 		return -ENODEV;
1113 	}
1114 
1115 	return 0;
1116 }
1117 
1118 void ltdc_suspend(struct drm_device *ddev)
1119 {
1120 	struct ltdc_device *ldev = ddev->dev_private;
1121 
1122 	DRM_DEBUG_DRIVER("\n");
1123 	clk_disable_unprepare(ldev->pixel_clk);
1124 }
1125 
1126 int ltdc_resume(struct drm_device *ddev)
1127 {
1128 	struct ltdc_device *ldev = ddev->dev_private;
1129 	int ret;
1130 
1131 	DRM_DEBUG_DRIVER("\n");
1132 
1133 	ret = clk_prepare_enable(ldev->pixel_clk);
1134 	if (ret) {
1135 		DRM_ERROR("failed to enable pixel clock (%d)\n", ret);
1136 		return ret;
1137 	}
1138 
1139 	return 0;
1140 }
1141 
1142 int ltdc_load(struct drm_device *ddev)
1143 {
1144 	struct platform_device *pdev = to_platform_device(ddev->dev);
1145 	struct ltdc_device *ldev = ddev->dev_private;
1146 	struct device *dev = ddev->dev;
1147 	struct device_node *np = dev->of_node;
1148 	struct drm_bridge *bridge[MAX_ENDPOINTS] = {NULL};
1149 	struct drm_panel *panel[MAX_ENDPOINTS] = {NULL};
1150 	struct drm_crtc *crtc;
1151 	struct reset_control *rstc;
1152 	struct resource *res;
1153 	int irq, ret, i, endpoint_not_ready = -ENODEV;
1154 
1155 	DRM_DEBUG_DRIVER("\n");
1156 
1157 	/* Get endpoints if any */
1158 	for (i = 0; i < MAX_ENDPOINTS; i++) {
1159 		ret = drm_of_find_panel_or_bridge(np, 0, i, &panel[i],
1160 						  &bridge[i]);
1161 
1162 		/*
1163 		 * If at least one endpoint is -EPROBE_DEFER, defer probing,
1164 		 * else if at least one endpoint is ready, continue probing.
1165 		 */
1166 		if (ret == -EPROBE_DEFER)
1167 			return ret;
1168 		else if (!ret)
1169 			endpoint_not_ready = 0;
1170 	}
1171 
1172 	if (endpoint_not_ready)
1173 		return endpoint_not_ready;
1174 
1175 	rstc = devm_reset_control_get_exclusive(dev, NULL);
1176 
1177 	mutex_init(&ldev->err_lock);
1178 
1179 	ldev->pixel_clk = devm_clk_get(dev, "lcd");
1180 	if (IS_ERR(ldev->pixel_clk)) {
1181 		if (PTR_ERR(ldev->pixel_clk) != -EPROBE_DEFER)
1182 			DRM_ERROR("Unable to get lcd clock\n");
1183 		return PTR_ERR(ldev->pixel_clk);
1184 	}
1185 
1186 	if (clk_prepare_enable(ldev->pixel_clk)) {
1187 		DRM_ERROR("Unable to prepare pixel clock\n");
1188 		return -ENODEV;
1189 	}
1190 
1191 	if (!IS_ERR(rstc)) {
1192 		reset_control_assert(rstc);
1193 		usleep_range(10, 20);
1194 		reset_control_deassert(rstc);
1195 	}
1196 
1197 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1198 	ldev->regs = devm_ioremap_resource(dev, res);
1199 	if (IS_ERR(ldev->regs)) {
1200 		DRM_ERROR("Unable to get ltdc registers\n");
1201 		ret = PTR_ERR(ldev->regs);
1202 		goto err;
1203 	}
1204 
1205 	/* Disable interrupts */
1206 	reg_clear(ldev->regs, LTDC_IER,
1207 		  IER_LIE | IER_RRIE | IER_FUIE | IER_TERRIE);
1208 
1209 	for (i = 0; i < MAX_IRQ; i++) {
1210 		irq = platform_get_irq(pdev, i);
1211 		if (irq == -EPROBE_DEFER)
1212 			goto err;
1213 
1214 		if (irq < 0)
1215 			continue;
1216 
1217 		ret = devm_request_threaded_irq(dev, irq, ltdc_irq,
1218 						ltdc_irq_thread, IRQF_ONESHOT,
1219 						dev_name(dev), ddev);
1220 		if (ret) {
1221 			DRM_ERROR("Failed to register LTDC interrupt\n");
1222 			goto err;
1223 		}
1224 	}
1225 
1226 
1227 	ret = ltdc_get_caps(ddev);
1228 	if (ret) {
1229 		DRM_ERROR("hardware identifier (0x%08x) not supported!\n",
1230 			  ldev->caps.hw_version);
1231 		goto err;
1232 	}
1233 
1234 	DRM_DEBUG_DRIVER("ltdc hw version 0x%08x\n", ldev->caps.hw_version);
1235 
1236 	/* Add endpoints panels or bridges if any */
1237 	for (i = 0; i < MAX_ENDPOINTS; i++) {
1238 		if (panel[i]) {
1239 			bridge[i] = drm_panel_bridge_add(panel[i],
1240 							DRM_MODE_CONNECTOR_DPI);
1241 			if (IS_ERR(bridge[i])) {
1242 				DRM_ERROR("panel-bridge endpoint %d\n", i);
1243 				ret = PTR_ERR(bridge[i]);
1244 				goto err;
1245 			}
1246 		}
1247 
1248 		if (bridge[i]) {
1249 			ret = ltdc_encoder_init(ddev, bridge[i]);
1250 			if (ret) {
1251 				DRM_ERROR("init encoder endpoint %d\n", i);
1252 				goto err;
1253 			}
1254 		}
1255 	}
1256 
1257 	crtc = devm_kzalloc(dev, sizeof(*crtc), GFP_KERNEL);
1258 	if (!crtc) {
1259 		DRM_ERROR("Failed to allocate crtc\n");
1260 		ret = -ENOMEM;
1261 		goto err;
1262 	}
1263 
1264 	ddev->mode_config.allow_fb_modifiers = true;
1265 
1266 	ret = ltdc_crtc_init(ddev, crtc);
1267 	if (ret) {
1268 		DRM_ERROR("Failed to init crtc\n");
1269 		goto err;
1270 	}
1271 
1272 	ret = drm_vblank_init(ddev, NB_CRTC);
1273 	if (ret) {
1274 		DRM_ERROR("Failed calling drm_vblank_init()\n");
1275 		goto err;
1276 	}
1277 
1278 	/* Allow usage of vblank without having to call drm_irq_install */
1279 	ddev->irq_enabled = 1;
1280 
1281 	clk_disable_unprepare(ldev->pixel_clk);
1282 
1283 	pm_runtime_enable(ddev->dev);
1284 
1285 	return 0;
1286 err:
1287 	for (i = 0; i < MAX_ENDPOINTS; i++)
1288 		drm_panel_bridge_remove(bridge[i]);
1289 
1290 	clk_disable_unprepare(ldev->pixel_clk);
1291 
1292 	return ret;
1293 }
1294 
1295 void ltdc_unload(struct drm_device *ddev)
1296 {
1297 	int i;
1298 
1299 	DRM_DEBUG_DRIVER("\n");
1300 
1301 	for (i = 0; i < MAX_ENDPOINTS; i++)
1302 		drm_of_panel_bridge_remove(ddev->dev->of_node, 0, i);
1303 
1304 	pm_runtime_disable(ddev->dev);
1305 }
1306 
1307 MODULE_AUTHOR("Philippe Cornu <philippe.cornu@st.com>");
1308 MODULE_AUTHOR("Yannick Fertre <yannick.fertre@st.com>");
1309 MODULE_AUTHOR("Fabien Dessenne <fabien.dessenne@st.com>");
1310 MODULE_AUTHOR("Mickael Reulier <mickael.reulier@st.com>");
1311 MODULE_DESCRIPTION("STMicroelectronics ST DRM LTDC driver");
1312 MODULE_LICENSE("GPL v2");
1313