xref: /openbmc/linux/drivers/gpu/drm/stm/ltdc.c (revision 28dce2c4)
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/pinctrl/consumer.h>
19 #include <linux/platform_device.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/reset.h>
22 
23 #include <drm/drm_atomic.h>
24 #include <drm/drm_atomic_helper.h>
25 #include <drm/drm_bridge.h>
26 #include <drm/drm_device.h>
27 #include <drm/drm_fb_cma_helper.h>
28 #include <drm/drm_fourcc.h>
29 #include <drm/drm_gem_atomic_helper.h>
30 #include <drm/drm_gem_cma_helper.h>
31 #include <drm/drm_of.h>
32 #include <drm/drm_plane_helper.h>
33 #include <drm/drm_probe_helper.h>
34 #include <drm/drm_simple_kms_helper.h>
35 #include <drm/drm_vblank.h>
36 
37 #include <video/videomode.h>
38 
39 #include "ltdc.h"
40 
41 #define NB_CRTC 1
42 #define CRTC_MASK GENMASK(NB_CRTC - 1, 0)
43 
44 #define MAX_IRQ 4
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_atomic_state *state)
425 {
426 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
427 	struct drm_device *ddev = crtc->dev;
428 
429 	DRM_DEBUG_DRIVER("\n");
430 
431 	pm_runtime_get_sync(ddev->dev);
432 
433 	/* Sets the background color value */
434 	reg_write(ldev->regs, LTDC_BCCR, BCCR_BCBLACK);
435 
436 	/* Enable IRQ */
437 	reg_set(ldev->regs, LTDC_IER, IER_RRIE | IER_FUIE | IER_TERRIE);
438 
439 	/* Commit shadow registers = update planes at next vblank */
440 	reg_set(ldev->regs, LTDC_SRCR, SRCR_VBR);
441 
442 	drm_crtc_vblank_on(crtc);
443 }
444 
445 static void ltdc_crtc_atomic_disable(struct drm_crtc *crtc,
446 				     struct drm_atomic_state *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 IRQ */
456 	reg_clear(ldev->regs, LTDC_IER, IER_RRIE | IER_FUIE | IER_TERRIE);
457 
458 	/* immediately commit disable of layers before switching off LTDC */
459 	reg_set(ldev->regs, LTDC_SRCR, SRCR_IMR);
460 
461 	pm_runtime_put_sync(ddev->dev);
462 }
463 
464 #define CLK_TOLERANCE_HZ 50
465 
466 static enum drm_mode_status
467 ltdc_crtc_mode_valid(struct drm_crtc *crtc,
468 		     const struct drm_display_mode *mode)
469 {
470 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
471 	int target = mode->clock * 1000;
472 	int target_min = target - CLK_TOLERANCE_HZ;
473 	int target_max = target + CLK_TOLERANCE_HZ;
474 	int result;
475 
476 	result = clk_round_rate(ldev->pixel_clk, target);
477 
478 	DRM_DEBUG_DRIVER("clk rate target %d, available %d\n", target, result);
479 
480 	/* Filter modes according to the max frequency supported by the pads */
481 	if (result > ldev->caps.pad_max_freq_hz)
482 		return MODE_CLOCK_HIGH;
483 
484 	/*
485 	 * Accept all "preferred" modes:
486 	 * - this is important for panels because panel clock tolerances are
487 	 *   bigger than hdmi ones and there is no reason to not accept them
488 	 *   (the fps may vary a little but it is not a problem).
489 	 * - the hdmi preferred mode will be accepted too, but userland will
490 	 *   be able to use others hdmi "valid" modes if necessary.
491 	 */
492 	if (mode->type & DRM_MODE_TYPE_PREFERRED)
493 		return MODE_OK;
494 
495 	/*
496 	 * Filter modes according to the clock value, particularly useful for
497 	 * hdmi modes that require precise pixel clocks.
498 	 */
499 	if (result < target_min || result > target_max)
500 		return MODE_CLOCK_RANGE;
501 
502 	return MODE_OK;
503 }
504 
505 static bool ltdc_crtc_mode_fixup(struct drm_crtc *crtc,
506 				 const struct drm_display_mode *mode,
507 				 struct drm_display_mode *adjusted_mode)
508 {
509 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
510 	int rate = mode->clock * 1000;
511 
512 	if (clk_set_rate(ldev->pixel_clk, rate) < 0) {
513 		DRM_ERROR("Cannot set rate (%dHz) for pixel clk\n", rate);
514 		return false;
515 	}
516 
517 	adjusted_mode->clock = clk_get_rate(ldev->pixel_clk) / 1000;
518 
519 	DRM_DEBUG_DRIVER("requested clock %dkHz, adjusted clock %dkHz\n",
520 			 mode->clock, adjusted_mode->clock);
521 
522 	return true;
523 }
524 
525 static void ltdc_crtc_mode_set_nofb(struct drm_crtc *crtc)
526 {
527 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
528 	struct drm_device *ddev = crtc->dev;
529 	struct drm_connector_list_iter iter;
530 	struct drm_connector *connector = NULL;
531 	struct drm_encoder *encoder = NULL;
532 	struct drm_bridge *bridge = NULL;
533 	struct drm_display_mode *mode = &crtc->state->adjusted_mode;
534 	struct videomode vm;
535 	u32 hsync, vsync, accum_hbp, accum_vbp, accum_act_w, accum_act_h;
536 	u32 total_width, total_height;
537 	u32 bus_flags = 0;
538 	u32 val;
539 	int ret;
540 
541 	/* get encoder from crtc */
542 	drm_for_each_encoder(encoder, ddev)
543 		if (encoder->crtc == crtc)
544 			break;
545 
546 	if (encoder) {
547 		/* get bridge from encoder */
548 		list_for_each_entry(bridge, &encoder->bridge_chain, chain_node)
549 			if (bridge->encoder == encoder)
550 				break;
551 
552 		/* Get the connector from encoder */
553 		drm_connector_list_iter_begin(ddev, &iter);
554 		drm_for_each_connector_iter(connector, &iter)
555 			if (connector->encoder == encoder)
556 				break;
557 		drm_connector_list_iter_end(&iter);
558 	}
559 
560 	if (bridge && bridge->timings)
561 		bus_flags = bridge->timings->input_bus_flags;
562 	else if (connector)
563 		bus_flags = connector->display_info.bus_flags;
564 
565 	if (!pm_runtime_active(ddev->dev)) {
566 		ret = pm_runtime_get_sync(ddev->dev);
567 		if (ret) {
568 			DRM_ERROR("Failed to set mode, cannot get sync\n");
569 			return;
570 		}
571 	}
572 
573 	drm_display_mode_to_videomode(mode, &vm);
574 
575 	DRM_DEBUG_DRIVER("CRTC:%d mode:%s\n", crtc->base.id, mode->name);
576 	DRM_DEBUG_DRIVER("Video mode: %dx%d", vm.hactive, vm.vactive);
577 	DRM_DEBUG_DRIVER(" hfp %d hbp %d hsl %d vfp %d vbp %d vsl %d\n",
578 			 vm.hfront_porch, vm.hback_porch, vm.hsync_len,
579 			 vm.vfront_porch, vm.vback_porch, vm.vsync_len);
580 
581 	/* Convert video timings to ltdc timings */
582 	hsync = vm.hsync_len - 1;
583 	vsync = vm.vsync_len - 1;
584 	accum_hbp = hsync + vm.hback_porch;
585 	accum_vbp = vsync + vm.vback_porch;
586 	accum_act_w = accum_hbp + vm.hactive;
587 	accum_act_h = accum_vbp + vm.vactive;
588 	total_width = accum_act_w + vm.hfront_porch;
589 	total_height = accum_act_h + vm.vfront_porch;
590 
591 	/* Configures the HS, VS, DE and PC polarities. Default Active Low */
592 	val = 0;
593 
594 	if (vm.flags & DISPLAY_FLAGS_HSYNC_HIGH)
595 		val |= GCR_HSPOL;
596 
597 	if (vm.flags & DISPLAY_FLAGS_VSYNC_HIGH)
598 		val |= GCR_VSPOL;
599 
600 	if (bus_flags & DRM_BUS_FLAG_DE_LOW)
601 		val |= GCR_DEPOL;
602 
603 	if (bus_flags & DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE)
604 		val |= GCR_PCPOL;
605 
606 	reg_update_bits(ldev->regs, LTDC_GCR,
607 			GCR_HSPOL | GCR_VSPOL | GCR_DEPOL | GCR_PCPOL, val);
608 
609 	/* Set Synchronization size */
610 	val = (hsync << 16) | vsync;
611 	reg_update_bits(ldev->regs, LTDC_SSCR, SSCR_VSH | SSCR_HSW, val);
612 
613 	/* Set Accumulated Back porch */
614 	val = (accum_hbp << 16) | accum_vbp;
615 	reg_update_bits(ldev->regs, LTDC_BPCR, BPCR_AVBP | BPCR_AHBP, val);
616 
617 	/* Set Accumulated Active Width */
618 	val = (accum_act_w << 16) | accum_act_h;
619 	reg_update_bits(ldev->regs, LTDC_AWCR, AWCR_AAW | AWCR_AAH, val);
620 
621 	/* Set total width & height */
622 	val = (total_width << 16) | total_height;
623 	reg_update_bits(ldev->regs, LTDC_TWCR, TWCR_TOTALH | TWCR_TOTALW, val);
624 
625 	reg_write(ldev->regs, LTDC_LIPCR, (accum_act_h + 1));
626 }
627 
628 static void ltdc_crtc_atomic_flush(struct drm_crtc *crtc,
629 				   struct drm_atomic_state *state)
630 {
631 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
632 	struct drm_device *ddev = crtc->dev;
633 	struct drm_pending_vblank_event *event = crtc->state->event;
634 
635 	DRM_DEBUG_ATOMIC("\n");
636 
637 	ltdc_crtc_update_clut(crtc);
638 
639 	/* Commit shadow registers = update planes at next vblank */
640 	reg_set(ldev->regs, LTDC_SRCR, SRCR_VBR);
641 
642 	if (event) {
643 		crtc->state->event = NULL;
644 
645 		spin_lock_irq(&ddev->event_lock);
646 		if (drm_crtc_vblank_get(crtc) == 0)
647 			drm_crtc_arm_vblank_event(crtc, event);
648 		else
649 			drm_crtc_send_vblank_event(crtc, event);
650 		spin_unlock_irq(&ddev->event_lock);
651 	}
652 }
653 
654 static bool ltdc_crtc_get_scanout_position(struct drm_crtc *crtc,
655 					   bool in_vblank_irq,
656 					   int *vpos, int *hpos,
657 					   ktime_t *stime, ktime_t *etime,
658 					   const struct drm_display_mode *mode)
659 {
660 	struct drm_device *ddev = crtc->dev;
661 	struct ltdc_device *ldev = ddev->dev_private;
662 	int line, vactive_start, vactive_end, vtotal;
663 
664 	if (stime)
665 		*stime = ktime_get();
666 
667 	/* The active area starts after vsync + front porch and ends
668 	 * at vsync + front porc + display size.
669 	 * The total height also include back porch.
670 	 * We have 3 possible cases to handle:
671 	 * - line < vactive_start: vpos = line - vactive_start and will be
672 	 * negative
673 	 * - vactive_start < line < vactive_end: vpos = line - vactive_start
674 	 * and will be positive
675 	 * - line > vactive_end: vpos = line - vtotal - vactive_start
676 	 * and will negative
677 	 *
678 	 * Computation for the two first cases are identical so we can
679 	 * simplify the code and only test if line > vactive_end
680 	 */
681 	if (pm_runtime_active(ddev->dev)) {
682 		line = reg_read(ldev->regs, LTDC_CPSR) & CPSR_CYPOS;
683 		vactive_start = reg_read(ldev->regs, LTDC_BPCR) & BPCR_AVBP;
684 		vactive_end = reg_read(ldev->regs, LTDC_AWCR) & AWCR_AAH;
685 		vtotal = reg_read(ldev->regs, LTDC_TWCR) & TWCR_TOTALH;
686 
687 		if (line > vactive_end)
688 			*vpos = line - vtotal - vactive_start;
689 		else
690 			*vpos = line - vactive_start;
691 	} else {
692 		*vpos = 0;
693 	}
694 
695 	*hpos = 0;
696 
697 	if (etime)
698 		*etime = ktime_get();
699 
700 	return true;
701 }
702 
703 static const struct drm_crtc_helper_funcs ltdc_crtc_helper_funcs = {
704 	.mode_valid = ltdc_crtc_mode_valid,
705 	.mode_fixup = ltdc_crtc_mode_fixup,
706 	.mode_set_nofb = ltdc_crtc_mode_set_nofb,
707 	.atomic_flush = ltdc_crtc_atomic_flush,
708 	.atomic_enable = ltdc_crtc_atomic_enable,
709 	.atomic_disable = ltdc_crtc_atomic_disable,
710 	.get_scanout_position = ltdc_crtc_get_scanout_position,
711 };
712 
713 static int ltdc_crtc_enable_vblank(struct drm_crtc *crtc)
714 {
715 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
716 	struct drm_crtc_state *state = crtc->state;
717 
718 	DRM_DEBUG_DRIVER("\n");
719 
720 	if (state->enable)
721 		reg_set(ldev->regs, LTDC_IER, IER_LIE);
722 	else
723 		return -EPERM;
724 
725 	return 0;
726 }
727 
728 static void ltdc_crtc_disable_vblank(struct drm_crtc *crtc)
729 {
730 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
731 
732 	DRM_DEBUG_DRIVER("\n");
733 	reg_clear(ldev->regs, LTDC_IER, IER_LIE);
734 }
735 
736 static const struct drm_crtc_funcs ltdc_crtc_funcs = {
737 	.destroy = drm_crtc_cleanup,
738 	.set_config = drm_atomic_helper_set_config,
739 	.page_flip = drm_atomic_helper_page_flip,
740 	.reset = drm_atomic_helper_crtc_reset,
741 	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
742 	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
743 	.enable_vblank = ltdc_crtc_enable_vblank,
744 	.disable_vblank = ltdc_crtc_disable_vblank,
745 	.get_vblank_timestamp = drm_crtc_vblank_helper_get_vblank_timestamp,
746 };
747 
748 /*
749  * DRM_PLANE
750  */
751 
752 static int ltdc_plane_atomic_check(struct drm_plane *plane,
753 				   struct drm_atomic_state *state)
754 {
755 	struct drm_plane_state *new_plane_state = drm_atomic_get_new_plane_state(state,
756 										 plane);
757 	struct drm_framebuffer *fb = new_plane_state->fb;
758 	u32 src_w, src_h;
759 
760 	DRM_DEBUG_DRIVER("\n");
761 
762 	if (!fb)
763 		return 0;
764 
765 	/* convert src_ from 16:16 format */
766 	src_w = new_plane_state->src_w >> 16;
767 	src_h = new_plane_state->src_h >> 16;
768 
769 	/* Reject scaling */
770 	if (src_w != new_plane_state->crtc_w || src_h != new_plane_state->crtc_h) {
771 		DRM_ERROR("Scaling is not supported");
772 		return -EINVAL;
773 	}
774 
775 	return 0;
776 }
777 
778 static void ltdc_plane_atomic_update(struct drm_plane *plane,
779 				     struct drm_atomic_state *state)
780 {
781 	struct ltdc_device *ldev = plane_to_ltdc(plane);
782 	struct drm_plane_state *newstate = drm_atomic_get_new_plane_state(state,
783 									  plane);
784 	struct drm_framebuffer *fb = newstate->fb;
785 	u32 lofs = plane->index * LAY_OFS;
786 	u32 x0 = newstate->crtc_x;
787 	u32 x1 = newstate->crtc_x + newstate->crtc_w - 1;
788 	u32 y0 = newstate->crtc_y;
789 	u32 y1 = newstate->crtc_y + newstate->crtc_h - 1;
790 	u32 src_x, src_y, src_w, src_h;
791 	u32 val, pitch_in_bytes, line_length, paddr, ahbp, avbp, bpcr;
792 	enum ltdc_pix_fmt pf;
793 
794 	if (!newstate->crtc || !fb) {
795 		DRM_DEBUG_DRIVER("fb or crtc NULL");
796 		return;
797 	}
798 
799 	/* convert src_ from 16:16 format */
800 	src_x = newstate->src_x >> 16;
801 	src_y = newstate->src_y >> 16;
802 	src_w = newstate->src_w >> 16;
803 	src_h = newstate->src_h >> 16;
804 
805 	DRM_DEBUG_DRIVER("plane:%d fb:%d (%dx%d)@(%d,%d) -> (%dx%d)@(%d,%d)\n",
806 			 plane->base.id, fb->base.id,
807 			 src_w, src_h, src_x, src_y,
808 			 newstate->crtc_w, newstate->crtc_h,
809 			 newstate->crtc_x, newstate->crtc_y);
810 
811 	bpcr = reg_read(ldev->regs, LTDC_BPCR);
812 	ahbp = (bpcr & BPCR_AHBP) >> 16;
813 	avbp = bpcr & BPCR_AVBP;
814 
815 	/* Configures the horizontal start and stop position */
816 	val = ((x1 + 1 + ahbp) << 16) + (x0 + 1 + ahbp);
817 	reg_update_bits(ldev->regs, LTDC_L1WHPCR + lofs,
818 			LXWHPCR_WHSTPOS | LXWHPCR_WHSPPOS, val);
819 
820 	/* Configures the vertical start and stop position */
821 	val = ((y1 + 1 + avbp) << 16) + (y0 + 1 + avbp);
822 	reg_update_bits(ldev->regs, LTDC_L1WVPCR + lofs,
823 			LXWVPCR_WVSTPOS | LXWVPCR_WVSPPOS, val);
824 
825 	/* Specifies the pixel format */
826 	pf = to_ltdc_pixelformat(fb->format->format);
827 	for (val = 0; val < NB_PF; val++)
828 		if (ldev->caps.pix_fmt_hw[val] == pf)
829 			break;
830 
831 	if (val == NB_PF) {
832 		DRM_ERROR("Pixel format %.4s not supported\n",
833 			  (char *)&fb->format->format);
834 		val = 0;	/* set by default ARGB 32 bits */
835 	}
836 	reg_update_bits(ldev->regs, LTDC_L1PFCR + lofs, LXPFCR_PF, val);
837 
838 	/* Configures the color frame buffer pitch in bytes & line length */
839 	pitch_in_bytes = fb->pitches[0];
840 	line_length = fb->format->cpp[0] *
841 		      (x1 - x0 + 1) + (ldev->caps.bus_width >> 3) - 1;
842 	val = ((pitch_in_bytes << 16) | line_length);
843 	reg_update_bits(ldev->regs, LTDC_L1CFBLR + lofs,
844 			LXCFBLR_CFBLL | LXCFBLR_CFBP, val);
845 
846 	/* Specifies the constant alpha value */
847 	val = CONSTA_MAX;
848 	reg_update_bits(ldev->regs, LTDC_L1CACR + lofs, LXCACR_CONSTA, val);
849 
850 	/* Specifies the blending factors */
851 	val = BF1_PAXCA | BF2_1PAXCA;
852 	if (!fb->format->has_alpha)
853 		val = BF1_CA | BF2_1CA;
854 
855 	/* Manage hw-specific capabilities */
856 	if (ldev->caps.non_alpha_only_l1 &&
857 	    plane->type != DRM_PLANE_TYPE_PRIMARY)
858 		val = BF1_PAXCA | BF2_1PAXCA;
859 
860 	reg_update_bits(ldev->regs, LTDC_L1BFCR + lofs,
861 			LXBFCR_BF2 | LXBFCR_BF1, val);
862 
863 	/* Configures the frame buffer line number */
864 	val = y1 - y0 + 1;
865 	reg_update_bits(ldev->regs, LTDC_L1CFBLNR + lofs, LXCFBLNR_CFBLN, val);
866 
867 	/* Sets the FB address */
868 	paddr = (u32)drm_fb_cma_get_gem_addr(fb, newstate, 0);
869 
870 	DRM_DEBUG_DRIVER("fb: phys 0x%08x", paddr);
871 	reg_write(ldev->regs, LTDC_L1CFBAR + lofs, paddr);
872 
873 	/* Enable layer and CLUT if needed */
874 	val = fb->format->format == DRM_FORMAT_C8 ? LXCR_CLUTEN : 0;
875 	val |= LXCR_LEN;
876 	reg_update_bits(ldev->regs, LTDC_L1CR + lofs,
877 			LXCR_LEN | LXCR_CLUTEN, val);
878 
879 	ldev->plane_fpsi[plane->index].counter++;
880 
881 	mutex_lock(&ldev->err_lock);
882 	if (ldev->error_status & ISR_FUIF) {
883 		DRM_WARN("ltdc fifo underrun: please verify display mode\n");
884 		ldev->error_status &= ~ISR_FUIF;
885 	}
886 	if (ldev->error_status & ISR_TERRIF) {
887 		DRM_WARN("ltdc transfer error\n");
888 		ldev->error_status &= ~ISR_TERRIF;
889 	}
890 	mutex_unlock(&ldev->err_lock);
891 }
892 
893 static void ltdc_plane_atomic_disable(struct drm_plane *plane,
894 				      struct drm_atomic_state *state)
895 {
896 	struct drm_plane_state *oldstate = drm_atomic_get_old_plane_state(state,
897 									  plane);
898 	struct ltdc_device *ldev = plane_to_ltdc(plane);
899 	u32 lofs = plane->index * LAY_OFS;
900 
901 	/* disable layer */
902 	reg_clear(ldev->regs, LTDC_L1CR + lofs, LXCR_LEN);
903 
904 	DRM_DEBUG_DRIVER("CRTC:%d plane:%d\n",
905 			 oldstate->crtc->base.id, plane->base.id);
906 }
907 
908 static void ltdc_plane_atomic_print_state(struct drm_printer *p,
909 					  const struct drm_plane_state *state)
910 {
911 	struct drm_plane *plane = state->plane;
912 	struct ltdc_device *ldev = plane_to_ltdc(plane);
913 	struct fps_info *fpsi = &ldev->plane_fpsi[plane->index];
914 	int ms_since_last;
915 	ktime_t now;
916 
917 	now = ktime_get();
918 	ms_since_last = ktime_to_ms(ktime_sub(now, fpsi->last_timestamp));
919 
920 	drm_printf(p, "\tuser_updates=%dfps\n",
921 		   DIV_ROUND_CLOSEST(fpsi->counter * 1000, ms_since_last));
922 
923 	fpsi->last_timestamp = now;
924 	fpsi->counter = 0;
925 }
926 
927 static bool ltdc_plane_format_mod_supported(struct drm_plane *plane,
928 					    u32 format,
929 					    u64 modifier)
930 {
931 	if (modifier == DRM_FORMAT_MOD_LINEAR)
932 		return true;
933 
934 	return false;
935 }
936 
937 static const struct drm_plane_funcs ltdc_plane_funcs = {
938 	.update_plane = drm_atomic_helper_update_plane,
939 	.disable_plane = drm_atomic_helper_disable_plane,
940 	.destroy = drm_plane_cleanup,
941 	.reset = drm_atomic_helper_plane_reset,
942 	.atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
943 	.atomic_destroy_state = drm_atomic_helper_plane_destroy_state,
944 	.atomic_print_state = ltdc_plane_atomic_print_state,
945 	.format_mod_supported = ltdc_plane_format_mod_supported,
946 };
947 
948 static const struct drm_plane_helper_funcs ltdc_plane_helper_funcs = {
949 	.prepare_fb = drm_gem_plane_helper_prepare_fb,
950 	.atomic_check = ltdc_plane_atomic_check,
951 	.atomic_update = ltdc_plane_atomic_update,
952 	.atomic_disable = ltdc_plane_atomic_disable,
953 };
954 
955 static struct drm_plane *ltdc_plane_create(struct drm_device *ddev,
956 					   enum drm_plane_type type)
957 {
958 	unsigned long possible_crtcs = CRTC_MASK;
959 	struct ltdc_device *ldev = ddev->dev_private;
960 	struct device *dev = ddev->dev;
961 	struct drm_plane *plane;
962 	unsigned int i, nb_fmt = 0;
963 	u32 formats[NB_PF * 2];
964 	u32 drm_fmt, drm_fmt_no_alpha;
965 	const u64 *modifiers = ltdc_format_modifiers;
966 	int ret;
967 
968 	/* Get supported pixel formats */
969 	for (i = 0; i < NB_PF; i++) {
970 		drm_fmt = to_drm_pixelformat(ldev->caps.pix_fmt_hw[i]);
971 		if (!drm_fmt)
972 			continue;
973 		formats[nb_fmt++] = drm_fmt;
974 
975 		/* Add the no-alpha related format if any & supported */
976 		drm_fmt_no_alpha = get_pixelformat_without_alpha(drm_fmt);
977 		if (!drm_fmt_no_alpha)
978 			continue;
979 
980 		/* Manage hw-specific capabilities */
981 		if (ldev->caps.non_alpha_only_l1 &&
982 		    type != DRM_PLANE_TYPE_PRIMARY)
983 			continue;
984 
985 		formats[nb_fmt++] = drm_fmt_no_alpha;
986 	}
987 
988 	plane = devm_kzalloc(dev, sizeof(*plane), GFP_KERNEL);
989 	if (!plane)
990 		return NULL;
991 
992 	ret = drm_universal_plane_init(ddev, plane, possible_crtcs,
993 				       &ltdc_plane_funcs, formats, nb_fmt,
994 				       modifiers, type, NULL);
995 	if (ret < 0)
996 		return NULL;
997 
998 	drm_plane_helper_add(plane, &ltdc_plane_helper_funcs);
999 
1000 	DRM_DEBUG_DRIVER("plane:%d created\n", plane->base.id);
1001 
1002 	return plane;
1003 }
1004 
1005 static void ltdc_plane_destroy_all(struct drm_device *ddev)
1006 {
1007 	struct drm_plane *plane, *plane_temp;
1008 
1009 	list_for_each_entry_safe(plane, plane_temp,
1010 				 &ddev->mode_config.plane_list, head)
1011 		drm_plane_cleanup(plane);
1012 }
1013 
1014 static int ltdc_crtc_init(struct drm_device *ddev, struct drm_crtc *crtc)
1015 {
1016 	struct ltdc_device *ldev = ddev->dev_private;
1017 	struct drm_plane *primary, *overlay;
1018 	unsigned int i;
1019 	int ret;
1020 
1021 	primary = ltdc_plane_create(ddev, DRM_PLANE_TYPE_PRIMARY);
1022 	if (!primary) {
1023 		DRM_ERROR("Can not create primary plane\n");
1024 		return -EINVAL;
1025 	}
1026 
1027 	ret = drm_crtc_init_with_planes(ddev, crtc, primary, NULL,
1028 					&ltdc_crtc_funcs, NULL);
1029 	if (ret) {
1030 		DRM_ERROR("Can not initialize CRTC\n");
1031 		goto cleanup;
1032 	}
1033 
1034 	drm_crtc_helper_add(crtc, &ltdc_crtc_helper_funcs);
1035 
1036 	drm_mode_crtc_set_gamma_size(crtc, CLUT_SIZE);
1037 	drm_crtc_enable_color_mgmt(crtc, 0, false, CLUT_SIZE);
1038 
1039 	DRM_DEBUG_DRIVER("CRTC:%d created\n", crtc->base.id);
1040 
1041 	/* Add planes. Note : the first layer is used by primary plane */
1042 	for (i = 1; i < ldev->caps.nb_layers; i++) {
1043 		overlay = ltdc_plane_create(ddev, DRM_PLANE_TYPE_OVERLAY);
1044 		if (!overlay) {
1045 			ret = -ENOMEM;
1046 			DRM_ERROR("Can not create overlay plane %d\n", i);
1047 			goto cleanup;
1048 		}
1049 	}
1050 
1051 	return 0;
1052 
1053 cleanup:
1054 	ltdc_plane_destroy_all(ddev);
1055 	return ret;
1056 }
1057 
1058 static void ltdc_encoder_disable(struct drm_encoder *encoder)
1059 {
1060 	struct drm_device *ddev = encoder->dev;
1061 	struct ltdc_device *ldev = ddev->dev_private;
1062 
1063 	DRM_DEBUG_DRIVER("\n");
1064 
1065 	/* Disable LTDC */
1066 	reg_clear(ldev->regs, LTDC_GCR, GCR_LTDCEN);
1067 
1068 	/* Set to sleep state the pinctrl whatever type of encoder */
1069 	pinctrl_pm_select_sleep_state(ddev->dev);
1070 }
1071 
1072 static void ltdc_encoder_enable(struct drm_encoder *encoder)
1073 {
1074 	struct drm_device *ddev = encoder->dev;
1075 	struct ltdc_device *ldev = ddev->dev_private;
1076 
1077 	DRM_DEBUG_DRIVER("\n");
1078 
1079 	/* Enable LTDC */
1080 	reg_set(ldev->regs, LTDC_GCR, GCR_LTDCEN);
1081 }
1082 
1083 static void ltdc_encoder_mode_set(struct drm_encoder *encoder,
1084 				  struct drm_display_mode *mode,
1085 				  struct drm_display_mode *adjusted_mode)
1086 {
1087 	struct drm_device *ddev = encoder->dev;
1088 
1089 	DRM_DEBUG_DRIVER("\n");
1090 
1091 	/*
1092 	 * Set to default state the pinctrl only with DPI type.
1093 	 * Others types like DSI, don't need pinctrl due to
1094 	 * internal bridge (the signals do not come out of the chipset).
1095 	 */
1096 	if (encoder->encoder_type == DRM_MODE_ENCODER_DPI)
1097 		pinctrl_pm_select_default_state(ddev->dev);
1098 }
1099 
1100 static const struct drm_encoder_helper_funcs ltdc_encoder_helper_funcs = {
1101 	.disable = ltdc_encoder_disable,
1102 	.enable = ltdc_encoder_enable,
1103 	.mode_set = ltdc_encoder_mode_set,
1104 };
1105 
1106 static int ltdc_encoder_init(struct drm_device *ddev, struct drm_bridge *bridge)
1107 {
1108 	struct drm_encoder *encoder;
1109 	int ret;
1110 
1111 	encoder = devm_kzalloc(ddev->dev, sizeof(*encoder), GFP_KERNEL);
1112 	if (!encoder)
1113 		return -ENOMEM;
1114 
1115 	encoder->possible_crtcs = CRTC_MASK;
1116 	encoder->possible_clones = 0;	/* No cloning support */
1117 
1118 	drm_simple_encoder_init(ddev, encoder, DRM_MODE_ENCODER_DPI);
1119 
1120 	drm_encoder_helper_add(encoder, &ltdc_encoder_helper_funcs);
1121 
1122 	ret = drm_bridge_attach(encoder, bridge, NULL, 0);
1123 	if (ret) {
1124 		drm_encoder_cleanup(encoder);
1125 		return -EINVAL;
1126 	}
1127 
1128 	DRM_DEBUG_DRIVER("Bridge encoder:%d created\n", encoder->base.id);
1129 
1130 	return 0;
1131 }
1132 
1133 static int ltdc_get_caps(struct drm_device *ddev)
1134 {
1135 	struct ltdc_device *ldev = ddev->dev_private;
1136 	u32 bus_width_log2, lcr, gc2r;
1137 
1138 	/*
1139 	 * at least 1 layer must be managed & the number of layers
1140 	 * must not exceed LTDC_MAX_LAYER
1141 	 */
1142 	lcr = reg_read(ldev->regs, LTDC_LCR);
1143 
1144 	ldev->caps.nb_layers = clamp((int)lcr, 1, LTDC_MAX_LAYER);
1145 
1146 	/* set data bus width */
1147 	gc2r = reg_read(ldev->regs, LTDC_GC2R);
1148 	bus_width_log2 = (gc2r & GC2R_BW) >> 4;
1149 	ldev->caps.bus_width = 8 << bus_width_log2;
1150 	ldev->caps.hw_version = reg_read(ldev->regs, LTDC_IDR);
1151 
1152 	switch (ldev->caps.hw_version) {
1153 	case HWVER_10200:
1154 	case HWVER_10300:
1155 		ldev->caps.reg_ofs = REG_OFS_NONE;
1156 		ldev->caps.pix_fmt_hw = ltdc_pix_fmt_a0;
1157 		/*
1158 		 * Hw older versions support non-alpha color formats derived
1159 		 * from native alpha color formats only on the primary layer.
1160 		 * For instance, RG16 native format without alpha works fine
1161 		 * on 2nd layer but XR24 (derived color format from AR24)
1162 		 * does not work on 2nd layer.
1163 		 */
1164 		ldev->caps.non_alpha_only_l1 = true;
1165 		ldev->caps.pad_max_freq_hz = 90000000;
1166 		if (ldev->caps.hw_version == HWVER_10200)
1167 			ldev->caps.pad_max_freq_hz = 65000000;
1168 		ldev->caps.nb_irq = 2;
1169 		break;
1170 	case HWVER_20101:
1171 		ldev->caps.reg_ofs = REG_OFS_4;
1172 		ldev->caps.pix_fmt_hw = ltdc_pix_fmt_a1;
1173 		ldev->caps.non_alpha_only_l1 = false;
1174 		ldev->caps.pad_max_freq_hz = 150000000;
1175 		ldev->caps.nb_irq = 4;
1176 		break;
1177 	default:
1178 		return -ENODEV;
1179 	}
1180 
1181 	return 0;
1182 }
1183 
1184 void ltdc_suspend(struct drm_device *ddev)
1185 {
1186 	struct ltdc_device *ldev = ddev->dev_private;
1187 
1188 	DRM_DEBUG_DRIVER("\n");
1189 	clk_disable_unprepare(ldev->pixel_clk);
1190 }
1191 
1192 int ltdc_resume(struct drm_device *ddev)
1193 {
1194 	struct ltdc_device *ldev = ddev->dev_private;
1195 	int ret;
1196 
1197 	DRM_DEBUG_DRIVER("\n");
1198 
1199 	ret = clk_prepare_enable(ldev->pixel_clk);
1200 	if (ret) {
1201 		DRM_ERROR("failed to enable pixel clock (%d)\n", ret);
1202 		return ret;
1203 	}
1204 
1205 	return 0;
1206 }
1207 
1208 int ltdc_load(struct drm_device *ddev)
1209 {
1210 	struct platform_device *pdev = to_platform_device(ddev->dev);
1211 	struct ltdc_device *ldev = ddev->dev_private;
1212 	struct device *dev = ddev->dev;
1213 	struct device_node *np = dev->of_node;
1214 	struct drm_bridge *bridge;
1215 	struct drm_panel *panel;
1216 	struct drm_crtc *crtc;
1217 	struct reset_control *rstc;
1218 	struct resource *res;
1219 	int irq, i, nb_endpoints;
1220 	int ret = -ENODEV;
1221 
1222 	DRM_DEBUG_DRIVER("\n");
1223 
1224 	/* Get number of endpoints */
1225 	nb_endpoints = of_graph_get_endpoint_count(np);
1226 	if (!nb_endpoints)
1227 		return -ENODEV;
1228 
1229 	ldev->pixel_clk = devm_clk_get(dev, "lcd");
1230 	if (IS_ERR(ldev->pixel_clk)) {
1231 		if (PTR_ERR(ldev->pixel_clk) != -EPROBE_DEFER)
1232 			DRM_ERROR("Unable to get lcd clock\n");
1233 		return PTR_ERR(ldev->pixel_clk);
1234 	}
1235 
1236 	if (clk_prepare_enable(ldev->pixel_clk)) {
1237 		DRM_ERROR("Unable to prepare pixel clock\n");
1238 		return -ENODEV;
1239 	}
1240 
1241 	/* Get endpoints if any */
1242 	for (i = 0; i < nb_endpoints; i++) {
1243 		ret = drm_of_find_panel_or_bridge(np, 0, i, &panel, &bridge);
1244 
1245 		/*
1246 		 * If at least one endpoint is -ENODEV, continue probing,
1247 		 * else if at least one endpoint returned an error
1248 		 * (ie -EPROBE_DEFER) then stop probing.
1249 		 */
1250 		if (ret == -ENODEV)
1251 			continue;
1252 		else if (ret)
1253 			goto err;
1254 
1255 		if (panel) {
1256 			bridge = drm_panel_bridge_add_typed(panel,
1257 							    DRM_MODE_CONNECTOR_DPI);
1258 			if (IS_ERR(bridge)) {
1259 				DRM_ERROR("panel-bridge endpoint %d\n", i);
1260 				ret = PTR_ERR(bridge);
1261 				goto err;
1262 			}
1263 		}
1264 
1265 		if (bridge) {
1266 			ret = ltdc_encoder_init(ddev, bridge);
1267 			if (ret) {
1268 				DRM_ERROR("init encoder endpoint %d\n", i);
1269 				goto err;
1270 			}
1271 		}
1272 	}
1273 
1274 	rstc = devm_reset_control_get_exclusive(dev, NULL);
1275 
1276 	mutex_init(&ldev->err_lock);
1277 
1278 	if (!IS_ERR(rstc)) {
1279 		reset_control_assert(rstc);
1280 		usleep_range(10, 20);
1281 		reset_control_deassert(rstc);
1282 	}
1283 
1284 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1285 	ldev->regs = devm_ioremap_resource(dev, res);
1286 	if (IS_ERR(ldev->regs)) {
1287 		DRM_ERROR("Unable to get ltdc registers\n");
1288 		ret = PTR_ERR(ldev->regs);
1289 		goto err;
1290 	}
1291 
1292 	/* Disable interrupts */
1293 	reg_clear(ldev->regs, LTDC_IER,
1294 		  IER_LIE | IER_RRIE | IER_FUIE | IER_TERRIE);
1295 
1296 	ret = ltdc_get_caps(ddev);
1297 	if (ret) {
1298 		DRM_ERROR("hardware identifier (0x%08x) not supported!\n",
1299 			  ldev->caps.hw_version);
1300 		goto err;
1301 	}
1302 
1303 	DRM_DEBUG_DRIVER("ltdc hw version 0x%08x\n", ldev->caps.hw_version);
1304 
1305 	for (i = 0; i < ldev->caps.nb_irq; i++) {
1306 		irq = platform_get_irq(pdev, i);
1307 		if (irq < 0) {
1308 			ret = irq;
1309 			goto err;
1310 		}
1311 
1312 		ret = devm_request_threaded_irq(dev, irq, ltdc_irq,
1313 						ltdc_irq_thread, IRQF_ONESHOT,
1314 						dev_name(dev), ddev);
1315 		if (ret) {
1316 			DRM_ERROR("Failed to register LTDC interrupt\n");
1317 			goto err;
1318 		}
1319 
1320 	}
1321 
1322 	crtc = devm_kzalloc(dev, sizeof(*crtc), GFP_KERNEL);
1323 	if (!crtc) {
1324 		DRM_ERROR("Failed to allocate crtc\n");
1325 		ret = -ENOMEM;
1326 		goto err;
1327 	}
1328 
1329 	ddev->mode_config.allow_fb_modifiers = true;
1330 
1331 	ret = ltdc_crtc_init(ddev, crtc);
1332 	if (ret) {
1333 		DRM_ERROR("Failed to init crtc\n");
1334 		goto err;
1335 	}
1336 
1337 	ret = drm_vblank_init(ddev, NB_CRTC);
1338 	if (ret) {
1339 		DRM_ERROR("Failed calling drm_vblank_init()\n");
1340 		goto err;
1341 	}
1342 
1343 	/* Allow usage of vblank without having to call drm_irq_install */
1344 	ddev->irq_enabled = 1;
1345 
1346 	clk_disable_unprepare(ldev->pixel_clk);
1347 
1348 	pinctrl_pm_select_sleep_state(ddev->dev);
1349 
1350 	pm_runtime_enable(ddev->dev);
1351 
1352 	return 0;
1353 err:
1354 	for (i = 0; i < nb_endpoints; i++)
1355 		drm_of_panel_bridge_remove(ddev->dev->of_node, 0, i);
1356 
1357 	clk_disable_unprepare(ldev->pixel_clk);
1358 
1359 	return ret;
1360 }
1361 
1362 void ltdc_unload(struct drm_device *ddev)
1363 {
1364 	struct device *dev = ddev->dev;
1365 	int nb_endpoints, i;
1366 
1367 	DRM_DEBUG_DRIVER("\n");
1368 
1369 	nb_endpoints = of_graph_get_endpoint_count(dev->of_node);
1370 
1371 	for (i = 0; i < nb_endpoints; i++)
1372 		drm_of_panel_bridge_remove(ddev->dev->of_node, 0, i);
1373 
1374 	pm_runtime_disable(ddev->dev);
1375 }
1376 
1377 MODULE_AUTHOR("Philippe Cornu <philippe.cornu@st.com>");
1378 MODULE_AUTHOR("Yannick Fertre <yannick.fertre@st.com>");
1379 MODULE_AUTHOR("Fabien Dessenne <fabien.dessenne@st.com>");
1380 MODULE_AUTHOR("Mickael Reulier <mickael.reulier@st.com>");
1381 MODULE_DESCRIPTION("STMicroelectronics ST DRM LTDC driver");
1382 MODULE_LICENSE("GPL v2");
1383