xref: /openbmc/linux/drivers/gpu/drm/stm/ltdc.c (revision 8ee90c5c)
1 /*
2  * Copyright (C) STMicroelectronics SA 2017
3  *
4  * Authors: Philippe Cornu <philippe.cornu@st.com>
5  *          Yannick Fertre <yannick.fertre@st.com>
6  *          Fabien Dessenne <fabien.dessenne@st.com>
7  *          Mickael Reulier <mickael.reulier@st.com>
8  *
9  * License terms:  GNU General Public License (GPL), version 2
10  */
11 
12 #include <linux/clk.h>
13 #include <linux/component.h>
14 #include <linux/of_address.h>
15 #include <linux/of_graph.h>
16 #include <linux/reset.h>
17 
18 #include <drm/drm_atomic.h>
19 #include <drm/drm_atomic_helper.h>
20 #include <drm/drm_crtc_helper.h>
21 #include <drm/drm_fb_cma_helper.h>
22 #include <drm/drm_gem_cma_helper.h>
23 #include <drm/drm_of.h>
24 #include <drm/drm_bridge.h>
25 #include <drm/drm_plane_helper.h>
26 
27 #include <video/videomode.h>
28 
29 #include "ltdc.h"
30 
31 #define NB_CRTC 1
32 #define CRTC_MASK GENMASK(NB_CRTC - 1, 0)
33 
34 #define MAX_IRQ 4
35 
36 #define HWVER_10200 0x010200
37 #define HWVER_10300 0x010300
38 #define HWVER_20101 0x020101
39 
40 /*
41  * The address of some registers depends on the HW version: such registers have
42  * an extra offset specified with reg_ofs.
43  */
44 #define REG_OFS_NONE	0
45 #define REG_OFS_4	4		/* Insertion of "Layer Conf. 2" reg */
46 #define REG_OFS		(ldev->caps.reg_ofs)
47 #define LAY_OFS		0x80		/* Register Offset between 2 layers */
48 
49 /* Global register offsets */
50 #define LTDC_IDR	0x0000		/* IDentification */
51 #define LTDC_LCR	0x0004		/* Layer Count */
52 #define LTDC_SSCR	0x0008		/* Synchronization Size Configuration */
53 #define LTDC_BPCR	0x000C		/* Back Porch Configuration */
54 #define LTDC_AWCR	0x0010		/* Active Width Configuration */
55 #define LTDC_TWCR	0x0014		/* Total Width Configuration */
56 #define LTDC_GCR	0x0018		/* Global Control */
57 #define LTDC_GC1R	0x001C		/* Global Configuration 1 */
58 #define LTDC_GC2R	0x0020		/* Global Configuration 2 */
59 #define LTDC_SRCR	0x0024		/* Shadow Reload Configuration */
60 #define LTDC_GACR	0x0028		/* GAmma Correction */
61 #define LTDC_BCCR	0x002C		/* Background Color Configuration */
62 #define LTDC_IER	0x0034		/* Interrupt Enable */
63 #define LTDC_ISR	0x0038		/* Interrupt Status */
64 #define LTDC_ICR	0x003C		/* Interrupt Clear */
65 #define LTDC_LIPCR	0x0040		/* Line Interrupt Position Conf. */
66 #define LTDC_CPSR	0x0044		/* Current Position Status */
67 #define LTDC_CDSR	0x0048		/* Current Display Status */
68 
69 /* Layer register offsets */
70 #define LTDC_L1LC1R	(0x80)		/* L1 Layer Configuration 1 */
71 #define LTDC_L1LC2R	(0x84)		/* L1 Layer Configuration 2 */
72 #define LTDC_L1CR	(0x84 + REG_OFS)/* L1 Control */
73 #define LTDC_L1WHPCR	(0x88 + REG_OFS)/* L1 Window Hor Position Config */
74 #define LTDC_L1WVPCR	(0x8C + REG_OFS)/* L1 Window Vert Position Config */
75 #define LTDC_L1CKCR	(0x90 + REG_OFS)/* L1 Color Keying Configuration */
76 #define LTDC_L1PFCR	(0x94 + REG_OFS)/* L1 Pixel Format Configuration */
77 #define LTDC_L1CACR	(0x98 + REG_OFS)/* L1 Constant Alpha Config */
78 #define LTDC_L1DCCR	(0x9C + REG_OFS)/* L1 Default Color Configuration */
79 #define LTDC_L1BFCR	(0xA0 + REG_OFS)/* L1 Blend Factors Configuration */
80 #define LTDC_L1FBBCR	(0xA4 + REG_OFS)/* L1 FrameBuffer Bus Control */
81 #define LTDC_L1AFBCR	(0xA8 + REG_OFS)/* L1 AuxFB Control */
82 #define LTDC_L1CFBAR	(0xAC + REG_OFS)/* L1 Color FrameBuffer Address */
83 #define LTDC_L1CFBLR	(0xB0 + REG_OFS)/* L1 Color FrameBuffer Length */
84 #define LTDC_L1CFBLNR	(0xB4 + REG_OFS)/* L1 Color FrameBuffer Line Nb */
85 #define LTDC_L1AFBAR	(0xB8 + REG_OFS)/* L1 AuxFB Address */
86 #define LTDC_L1AFBLR	(0xBC + REG_OFS)/* L1 AuxFB Length */
87 #define LTDC_L1AFBLNR	(0xC0 + REG_OFS)/* L1 AuxFB Line Number */
88 #define LTDC_L1CLUTWR	(0xC4 + REG_OFS)/* L1 CLUT Write */
89 #define LTDC_L1YS1R	(0xE0 + REG_OFS)/* L1 YCbCr Scale 1 */
90 #define LTDC_L1YS2R	(0xE4 + REG_OFS)/* L1 YCbCr Scale 2 */
91 
92 /* Bit definitions */
93 #define SSCR_VSH	GENMASK(10, 0)	/* Vertical Synchronization Height */
94 #define SSCR_HSW	GENMASK(27, 16)	/* Horizontal Synchronization Width */
95 
96 #define BPCR_AVBP	GENMASK(10, 0)	/* Accumulated Vertical Back Porch */
97 #define BPCR_AHBP	GENMASK(27, 16)	/* Accumulated Horizontal Back Porch */
98 
99 #define AWCR_AAH	GENMASK(10, 0)	/* Accumulated Active Height */
100 #define AWCR_AAW	GENMASK(27, 16)	/* Accumulated Active Width */
101 
102 #define TWCR_TOTALH	GENMASK(10, 0)	/* TOTAL Height */
103 #define TWCR_TOTALW	GENMASK(27, 16)	/* TOTAL Width */
104 
105 #define GCR_LTDCEN	BIT(0)		/* LTDC ENable */
106 #define GCR_DEN		BIT(16)		/* Dither ENable */
107 #define GCR_PCPOL	BIT(28)		/* Pixel Clock POLarity-Inverted */
108 #define GCR_DEPOL	BIT(29)		/* Data Enable POLarity-High */
109 #define GCR_VSPOL	BIT(30)		/* Vertical Synchro POLarity-High */
110 #define GCR_HSPOL	BIT(31)		/* Horizontal Synchro POLarity-High */
111 
112 #define GC1R_WBCH	GENMASK(3, 0)	/* Width of Blue CHannel output */
113 #define GC1R_WGCH	GENMASK(7, 4)	/* Width of Green Channel output */
114 #define GC1R_WRCH	GENMASK(11, 8)	/* Width of Red Channel output */
115 #define GC1R_PBEN	BIT(12)		/* Precise Blending ENable */
116 #define GC1R_DT		GENMASK(15, 14)	/* Dithering Technique */
117 #define GC1R_GCT	GENMASK(19, 17)	/* Gamma Correction Technique */
118 #define GC1R_SHREN	BIT(21)		/* SHadow Registers ENabled */
119 #define GC1R_BCP	BIT(22)		/* Background Colour Programmable */
120 #define GC1R_BBEN	BIT(23)		/* Background Blending ENabled */
121 #define GC1R_LNIP	BIT(24)		/* Line Number IRQ Position */
122 #define GC1R_TP		BIT(25)		/* Timing Programmable */
123 #define GC1R_IPP	BIT(26)		/* IRQ Polarity Programmable */
124 #define GC1R_SPP	BIT(27)		/* Sync Polarity Programmable */
125 #define GC1R_DWP	BIT(28)		/* Dither Width Programmable */
126 #define GC1R_STREN	BIT(29)		/* STatus Registers ENabled */
127 #define GC1R_BMEN	BIT(31)		/* Blind Mode ENabled */
128 
129 #define GC2R_EDCA	BIT(0)		/* External Display Control Ability  */
130 #define GC2R_STSAEN	BIT(1)		/* Slave Timing Sync Ability ENabled */
131 #define GC2R_DVAEN	BIT(2)		/* Dual-View Ability ENabled */
132 #define GC2R_DPAEN	BIT(3)		/* Dual-Port Ability ENabled */
133 #define GC2R_BW		GENMASK(6, 4)	/* Bus Width (log2 of nb of bytes) */
134 #define GC2R_EDCEN	BIT(7)		/* External Display Control ENabled */
135 
136 #define SRCR_IMR	BIT(0)		/* IMmediate Reload */
137 #define SRCR_VBR	BIT(1)		/* Vertical Blanking Reload */
138 
139 #define BCCR_BCBLACK	0x00		/* Background Color BLACK */
140 #define BCCR_BCBLUE	GENMASK(7, 0)	/* Background Color BLUE */
141 #define BCCR_BCGREEN	GENMASK(15, 8)	/* Background Color GREEN */
142 #define BCCR_BCRED	GENMASK(23, 16)	/* Background Color RED */
143 #define BCCR_BCWHITE	GENMASK(23, 0)	/* Background Color WHITE */
144 
145 #define IER_LIE		BIT(0)		/* Line Interrupt Enable */
146 #define IER_FUIE	BIT(1)		/* Fifo Underrun Interrupt Enable */
147 #define IER_TERRIE	BIT(2)		/* Transfer ERRor Interrupt Enable */
148 #define IER_RRIE	BIT(3)		/* Register Reload Interrupt enable */
149 
150 #define ISR_LIF		BIT(0)		/* Line Interrupt Flag */
151 #define ISR_FUIF	BIT(1)		/* Fifo Underrun Interrupt Flag */
152 #define ISR_TERRIF	BIT(2)		/* Transfer ERRor Interrupt Flag */
153 #define ISR_RRIF	BIT(3)		/* Register Reload Interrupt Flag */
154 
155 #define LXCR_LEN	BIT(0)		/* Layer ENable */
156 #define LXCR_COLKEN	BIT(1)		/* Color Keying Enable */
157 #define LXCR_CLUTEN	BIT(4)		/* Color Look-Up Table ENable */
158 
159 #define LXWHPCR_WHSTPOS	GENMASK(11, 0)	/* Window Horizontal StarT POSition */
160 #define LXWHPCR_WHSPPOS	GENMASK(27, 16)	/* Window Horizontal StoP POSition */
161 
162 #define LXWVPCR_WVSTPOS	GENMASK(10, 0)	/* Window Vertical StarT POSition */
163 #define LXWVPCR_WVSPPOS	GENMASK(26, 16)	/* Window Vertical StoP POSition */
164 
165 #define LXPFCR_PF	GENMASK(2, 0)	/* Pixel Format */
166 
167 #define LXCACR_CONSTA	GENMASK(7, 0)	/* CONSTant Alpha */
168 
169 #define LXBFCR_BF2	GENMASK(2, 0)	/* Blending Factor 2 */
170 #define LXBFCR_BF1	GENMASK(10, 8)	/* Blending Factor 1 */
171 
172 #define LXCFBLR_CFBLL	GENMASK(12, 0)	/* Color Frame Buffer Line Length */
173 #define LXCFBLR_CFBP	GENMASK(28, 16)	/* Color Frame Buffer Pitch in bytes */
174 
175 #define LXCFBLNR_CFBLN	GENMASK(10, 0)	/* Color Frame Buffer Line Number */
176 
177 #define CONSTA_MAX	0xFF		/* CONSTant Alpha MAX= 1.0 */
178 #define BF1_PAXCA	0x600		/* Pixel Alpha x Constant Alpha */
179 #define BF1_CA		0x400		/* Constant Alpha */
180 #define BF2_1PAXCA	0x007		/* 1 - (Pixel Alpha x Constant Alpha) */
181 #define BF2_1CA		0x005		/* 1 - Constant Alpha */
182 
183 #define NB_PF		8		/* Max nb of HW pixel format */
184 
185 enum ltdc_pix_fmt {
186 	PF_NONE,
187 	/* RGB formats */
188 	PF_ARGB8888,		/* ARGB [32 bits] */
189 	PF_RGBA8888,		/* RGBA [32 bits] */
190 	PF_RGB888,		/* RGB [24 bits] */
191 	PF_RGB565,		/* RGB [16 bits] */
192 	PF_ARGB1555,		/* ARGB A:1 bit RGB:15 bits [16 bits] */
193 	PF_ARGB4444,		/* ARGB A:4 bits R/G/B: 4 bits each [16 bits] */
194 	/* Indexed formats */
195 	PF_L8,			/* Indexed 8 bits [8 bits] */
196 	PF_AL44,		/* Alpha:4 bits + indexed 4 bits [8 bits] */
197 	PF_AL88			/* Alpha:8 bits + indexed 8 bits [16 bits] */
198 };
199 
200 /* The index gives the encoding of the pixel format for an HW version */
201 static const enum ltdc_pix_fmt ltdc_pix_fmt_a0[NB_PF] = {
202 	PF_ARGB8888,		/* 0x00 */
203 	PF_RGB888,		/* 0x01 */
204 	PF_RGB565,		/* 0x02 */
205 	PF_ARGB1555,		/* 0x03 */
206 	PF_ARGB4444,		/* 0x04 */
207 	PF_L8,			/* 0x05 */
208 	PF_AL44,		/* 0x06 */
209 	PF_AL88			/* 0x07 */
210 };
211 
212 static const enum ltdc_pix_fmt ltdc_pix_fmt_a1[NB_PF] = {
213 	PF_ARGB8888,		/* 0x00 */
214 	PF_RGB888,		/* 0x01 */
215 	PF_RGB565,		/* 0x02 */
216 	PF_RGBA8888,		/* 0x03 */
217 	PF_AL44,		/* 0x04 */
218 	PF_L8,			/* 0x05 */
219 	PF_ARGB1555,		/* 0x06 */
220 	PF_ARGB4444		/* 0x07 */
221 };
222 
223 static inline u32 reg_read(void __iomem *base, u32 reg)
224 {
225 	return readl_relaxed(base + reg);
226 }
227 
228 static inline void reg_write(void __iomem *base, u32 reg, u32 val)
229 {
230 	writel_relaxed(val, base + reg);
231 }
232 
233 static inline void reg_set(void __iomem *base, u32 reg, u32 mask)
234 {
235 	reg_write(base, reg, reg_read(base, reg) | mask);
236 }
237 
238 static inline void reg_clear(void __iomem *base, u32 reg, u32 mask)
239 {
240 	reg_write(base, reg, reg_read(base, reg) & ~mask);
241 }
242 
243 static inline void reg_update_bits(void __iomem *base, u32 reg, u32 mask,
244 				   u32 val)
245 {
246 	reg_write(base, reg, (reg_read(base, reg) & ~mask) | val);
247 }
248 
249 static inline struct ltdc_device *crtc_to_ltdc(struct drm_crtc *crtc)
250 {
251 	return (struct ltdc_device *)crtc->dev->dev_private;
252 }
253 
254 static inline struct ltdc_device *plane_to_ltdc(struct drm_plane *plane)
255 {
256 	return (struct ltdc_device *)plane->dev->dev_private;
257 }
258 
259 static inline struct ltdc_device *encoder_to_ltdc(struct drm_encoder *enc)
260 {
261 	return (struct ltdc_device *)enc->dev->dev_private;
262 }
263 
264 static inline enum ltdc_pix_fmt to_ltdc_pixelformat(u32 drm_fmt)
265 {
266 	enum ltdc_pix_fmt pf;
267 
268 	switch (drm_fmt) {
269 	case DRM_FORMAT_ARGB8888:
270 	case DRM_FORMAT_XRGB8888:
271 		pf = PF_ARGB8888;
272 		break;
273 	case DRM_FORMAT_RGBA8888:
274 	case DRM_FORMAT_RGBX8888:
275 		pf = PF_RGBA8888;
276 		break;
277 	case DRM_FORMAT_RGB888:
278 		pf = PF_RGB888;
279 		break;
280 	case DRM_FORMAT_RGB565:
281 		pf = PF_RGB565;
282 		break;
283 	case DRM_FORMAT_ARGB1555:
284 	case DRM_FORMAT_XRGB1555:
285 		pf = PF_ARGB1555;
286 		break;
287 	case DRM_FORMAT_ARGB4444:
288 	case DRM_FORMAT_XRGB4444:
289 		pf = PF_ARGB4444;
290 		break;
291 	case DRM_FORMAT_C8:
292 		pf = PF_L8;
293 		break;
294 	default:
295 		pf = PF_NONE;
296 		break;
297 		/* Note: There are no DRM_FORMAT for AL44 and AL88 */
298 	}
299 
300 	return pf;
301 }
302 
303 static inline u32 to_drm_pixelformat(enum ltdc_pix_fmt pf)
304 {
305 	switch (pf) {
306 	case PF_ARGB8888:
307 		return DRM_FORMAT_ARGB8888;
308 	case PF_RGBA8888:
309 		return DRM_FORMAT_RGBA8888;
310 	case PF_RGB888:
311 		return DRM_FORMAT_RGB888;
312 	case PF_RGB565:
313 		return DRM_FORMAT_RGB565;
314 	case PF_ARGB1555:
315 		return DRM_FORMAT_ARGB1555;
316 	case PF_ARGB4444:
317 		return DRM_FORMAT_ARGB4444;
318 	case PF_L8:
319 		return DRM_FORMAT_C8;
320 	case PF_AL44:		/* No DRM support */
321 	case PF_AL88:		/* No DRM support */
322 	case PF_NONE:
323 	default:
324 		return 0;
325 	}
326 }
327 
328 static irqreturn_t ltdc_irq_thread(int irq, void *arg)
329 {
330 	struct drm_device *ddev = arg;
331 	struct ltdc_device *ldev = ddev->dev_private;
332 	struct drm_crtc *crtc = drm_crtc_from_index(ddev, 0);
333 
334 	/* Line IRQ : trigger the vblank event */
335 	if (ldev->irq_status & ISR_LIF)
336 		drm_crtc_handle_vblank(crtc);
337 
338 	/* Save FIFO Underrun & Transfer Error status */
339 	mutex_lock(&ldev->err_lock);
340 	if (ldev->irq_status & ISR_FUIF)
341 		ldev->error_status |= ISR_FUIF;
342 	if (ldev->irq_status & ISR_TERRIF)
343 		ldev->error_status |= ISR_TERRIF;
344 	mutex_unlock(&ldev->err_lock);
345 
346 	return IRQ_HANDLED;
347 }
348 
349 static irqreturn_t ltdc_irq(int irq, void *arg)
350 {
351 	struct drm_device *ddev = arg;
352 	struct ltdc_device *ldev = ddev->dev_private;
353 
354 	/* Read & Clear the interrupt status */
355 	ldev->irq_status = reg_read(ldev->regs, LTDC_ISR);
356 	reg_write(ldev->regs, LTDC_ICR, ldev->irq_status);
357 
358 	return IRQ_WAKE_THREAD;
359 }
360 
361 /*
362  * DRM_CRTC
363  */
364 
365 static void ltdc_crtc_atomic_enable(struct drm_crtc *crtc,
366 				    struct drm_crtc_state *old_state)
367 {
368 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
369 
370 	DRM_DEBUG_DRIVER("\n");
371 
372 	/* Sets the background color value */
373 	reg_write(ldev->regs, LTDC_BCCR, BCCR_BCBLACK);
374 
375 	/* Enable IRQ */
376 	reg_set(ldev->regs, LTDC_IER, IER_RRIE | IER_FUIE | IER_TERRIE);
377 
378 	/* Immediately commit the planes */
379 	reg_set(ldev->regs, LTDC_SRCR, SRCR_IMR);
380 
381 	/* Enable LTDC */
382 	reg_set(ldev->regs, LTDC_GCR, GCR_LTDCEN);
383 
384 	drm_crtc_vblank_on(crtc);
385 }
386 
387 static void ltdc_crtc_atomic_disable(struct drm_crtc *crtc,
388 				     struct drm_crtc_state *old_state)
389 {
390 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
391 
392 	DRM_DEBUG_DRIVER("\n");
393 
394 	drm_crtc_vblank_off(crtc);
395 
396 	/* disable LTDC */
397 	reg_clear(ldev->regs, LTDC_GCR, GCR_LTDCEN);
398 
399 	/* disable IRQ */
400 	reg_clear(ldev->regs, LTDC_IER, IER_RRIE | IER_FUIE | IER_TERRIE);
401 
402 	/* immediately commit disable of layers before switching off LTDC */
403 	reg_set(ldev->regs, LTDC_SRCR, SRCR_IMR);
404 }
405 
406 static void ltdc_crtc_mode_set_nofb(struct drm_crtc *crtc)
407 {
408 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
409 	struct drm_display_mode *mode = &crtc->state->adjusted_mode;
410 	struct videomode vm;
411 	int rate = mode->clock * 1000;
412 	u32 hsync, vsync, accum_hbp, accum_vbp, accum_act_w, accum_act_h;
413 	u32 total_width, total_height;
414 	u32 val;
415 
416 	drm_display_mode_to_videomode(mode, &vm);
417 
418 	DRM_DEBUG_DRIVER("CRTC:%d mode:%s\n", crtc->base.id, mode->name);
419 	DRM_DEBUG_DRIVER("Video mode: %dx%d", vm.hactive, vm.vactive);
420 	DRM_DEBUG_DRIVER(" hfp %d hbp %d hsl %d vfp %d vbp %d vsl %d\n",
421 			 vm.hfront_porch, vm.hback_porch, vm.hsync_len,
422 			 vm.vfront_porch, vm.vback_porch, vm.vsync_len);
423 
424 	/* Convert video timings to ltdc timings */
425 	hsync = vm.hsync_len - 1;
426 	vsync = vm.vsync_len - 1;
427 	accum_hbp = hsync + vm.hback_porch;
428 	accum_vbp = vsync + vm.vback_porch;
429 	accum_act_w = accum_hbp + vm.hactive;
430 	accum_act_h = accum_vbp + vm.vactive;
431 	total_width = accum_act_w + vm.hfront_porch;
432 	total_height = accum_act_h + vm.vfront_porch;
433 
434 	clk_disable(ldev->pixel_clk);
435 
436 	if (clk_set_rate(ldev->pixel_clk, rate) < 0) {
437 		DRM_ERROR("Cannot set rate (%dHz) for pixel clk\n", rate);
438 		return;
439 	}
440 
441 	clk_enable(ldev->pixel_clk);
442 
443 	/* Configures the HS, VS, DE and PC polarities. Default Active Low */
444 	val = 0;
445 
446 	if (vm.flags & DISPLAY_FLAGS_HSYNC_HIGH)
447 		val |= GCR_HSPOL;
448 
449 	if (vm.flags & DISPLAY_FLAGS_VSYNC_HIGH)
450 		val |= GCR_VSPOL;
451 
452 	if (vm.flags & DISPLAY_FLAGS_DE_HIGH)
453 		val |= GCR_DEPOL;
454 
455 	if (vm.flags & DISPLAY_FLAGS_PIXDATA_NEGEDGE)
456 		val |= GCR_PCPOL;
457 
458 	reg_update_bits(ldev->regs, LTDC_GCR,
459 			GCR_HSPOL | GCR_VSPOL | GCR_DEPOL | GCR_PCPOL, val);
460 
461 	/* Set Synchronization size */
462 	val = (hsync << 16) | vsync;
463 	reg_update_bits(ldev->regs, LTDC_SSCR, SSCR_VSH | SSCR_HSW, val);
464 
465 	/* Set Accumulated Back porch */
466 	val = (accum_hbp << 16) | accum_vbp;
467 	reg_update_bits(ldev->regs, LTDC_BPCR, BPCR_AVBP | BPCR_AHBP, val);
468 
469 	/* Set Accumulated Active Width */
470 	val = (accum_act_w << 16) | accum_act_h;
471 	reg_update_bits(ldev->regs, LTDC_AWCR, AWCR_AAW | AWCR_AAH, val);
472 
473 	/* Set total width & height */
474 	val = (total_width << 16) | total_height;
475 	reg_update_bits(ldev->regs, LTDC_TWCR, TWCR_TOTALH | TWCR_TOTALW, val);
476 
477 	reg_write(ldev->regs, LTDC_LIPCR, (accum_act_h + 1));
478 }
479 
480 static void ltdc_crtc_atomic_flush(struct drm_crtc *crtc,
481 				   struct drm_crtc_state *old_crtc_state)
482 {
483 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
484 	struct drm_pending_vblank_event *event = crtc->state->event;
485 
486 	DRM_DEBUG_ATOMIC("\n");
487 
488 	/* Commit shadow registers = update planes at next vblank */
489 	reg_set(ldev->regs, LTDC_SRCR, SRCR_VBR);
490 
491 	if (event) {
492 		crtc->state->event = NULL;
493 
494 		spin_lock_irq(&crtc->dev->event_lock);
495 		if (drm_crtc_vblank_get(crtc) == 0)
496 			drm_crtc_arm_vblank_event(crtc, event);
497 		else
498 			drm_crtc_send_vblank_event(crtc, event);
499 		spin_unlock_irq(&crtc->dev->event_lock);
500 	}
501 }
502 
503 static const struct drm_crtc_helper_funcs ltdc_crtc_helper_funcs = {
504 	.mode_set_nofb = ltdc_crtc_mode_set_nofb,
505 	.atomic_flush = ltdc_crtc_atomic_flush,
506 	.atomic_enable = ltdc_crtc_atomic_enable,
507 	.atomic_disable = ltdc_crtc_atomic_disable,
508 };
509 
510 int ltdc_crtc_enable_vblank(struct drm_device *ddev, unsigned int pipe)
511 {
512 	struct ltdc_device *ldev = ddev->dev_private;
513 
514 	DRM_DEBUG_DRIVER("\n");
515 	reg_set(ldev->regs, LTDC_IER, IER_LIE);
516 
517 	return 0;
518 }
519 
520 void ltdc_crtc_disable_vblank(struct drm_device *ddev, unsigned int pipe)
521 {
522 	struct ltdc_device *ldev = ddev->dev_private;
523 
524 	DRM_DEBUG_DRIVER("\n");
525 	reg_clear(ldev->regs, LTDC_IER, IER_LIE);
526 }
527 
528 static const struct drm_crtc_funcs ltdc_crtc_funcs = {
529 	.destroy = drm_crtc_cleanup,
530 	.set_config = drm_atomic_helper_set_config,
531 	.page_flip = drm_atomic_helper_page_flip,
532 	.reset = drm_atomic_helper_crtc_reset,
533 	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
534 	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
535 };
536 
537 /*
538  * DRM_PLANE
539  */
540 
541 static int ltdc_plane_atomic_check(struct drm_plane *plane,
542 				   struct drm_plane_state *state)
543 {
544 	struct drm_framebuffer *fb = state->fb;
545 	u32 src_x, src_y, src_w, src_h;
546 
547 	DRM_DEBUG_DRIVER("\n");
548 
549 	if (!fb)
550 		return 0;
551 
552 	/* convert src_ from 16:16 format */
553 	src_x = state->src_x >> 16;
554 	src_y = state->src_y >> 16;
555 	src_w = state->src_w >> 16;
556 	src_h = state->src_h >> 16;
557 
558 	/* Reject scaling */
559 	if ((src_w != state->crtc_w) || (src_h != state->crtc_h)) {
560 		DRM_ERROR("Scaling is not supported");
561 		return -EINVAL;
562 	}
563 
564 	return 0;
565 }
566 
567 static void ltdc_plane_atomic_update(struct drm_plane *plane,
568 				     struct drm_plane_state *oldstate)
569 {
570 	struct ltdc_device *ldev = plane_to_ltdc(plane);
571 	struct drm_plane_state *state = plane->state;
572 	struct drm_framebuffer *fb = state->fb;
573 	u32 lofs = plane->index * LAY_OFS;
574 	u32 x0 = state->crtc_x;
575 	u32 x1 = state->crtc_x + state->crtc_w - 1;
576 	u32 y0 = state->crtc_y;
577 	u32 y1 = state->crtc_y + state->crtc_h - 1;
578 	u32 src_x, src_y, src_w, src_h;
579 	u32 val, pitch_in_bytes, line_length, paddr, ahbp, avbp, bpcr;
580 	enum ltdc_pix_fmt pf;
581 
582 	if (!state->crtc || !fb) {
583 		DRM_DEBUG_DRIVER("fb or crtc NULL");
584 		return;
585 	}
586 
587 	/* convert src_ from 16:16 format */
588 	src_x = state->src_x >> 16;
589 	src_y = state->src_y >> 16;
590 	src_w = state->src_w >> 16;
591 	src_h = state->src_h >> 16;
592 
593 	DRM_DEBUG_DRIVER("plane:%d fb:%d (%dx%d)@(%d,%d) -> (%dx%d)@(%d,%d)\n",
594 			 plane->base.id, fb->base.id,
595 			 src_w, src_h, src_x, src_y,
596 			 state->crtc_w, state->crtc_h,
597 			 state->crtc_x, state->crtc_y);
598 
599 	bpcr = reg_read(ldev->regs, LTDC_BPCR);
600 	ahbp = (bpcr & BPCR_AHBP) >> 16;
601 	avbp = bpcr & BPCR_AVBP;
602 
603 	/* Configures the horizontal start and stop position */
604 	val = ((x1 + 1 + ahbp) << 16) + (x0 + 1 + ahbp);
605 	reg_update_bits(ldev->regs, LTDC_L1WHPCR + lofs,
606 			LXWHPCR_WHSTPOS | LXWHPCR_WHSPPOS, val);
607 
608 	/* Configures the vertical start and stop position */
609 	val = ((y1 + 1 + avbp) << 16) + (y0 + 1 + avbp);
610 	reg_update_bits(ldev->regs, LTDC_L1WVPCR + lofs,
611 			LXWVPCR_WVSTPOS | LXWVPCR_WVSPPOS, val);
612 
613 	/* Specifies the pixel format */
614 	pf = to_ltdc_pixelformat(fb->format->format);
615 	for (val = 0; val < NB_PF; val++)
616 		if (ldev->caps.pix_fmt_hw[val] == pf)
617 			break;
618 
619 	if (val == NB_PF) {
620 		DRM_ERROR("Pixel format %.4s not supported\n",
621 			  (char *)&fb->format->format);
622 		val = 0;	/* set by default ARGB 32 bits */
623 	}
624 	reg_update_bits(ldev->regs, LTDC_L1PFCR + lofs, LXPFCR_PF, val);
625 
626 	/* Configures the color frame buffer pitch in bytes & line length */
627 	pitch_in_bytes = fb->pitches[0];
628 	line_length = drm_format_plane_cpp(fb->format->format, 0) *
629 		      (x1 - x0 + 1) + (ldev->caps.bus_width >> 3) - 1;
630 	val = ((pitch_in_bytes << 16) | line_length);
631 	reg_update_bits(ldev->regs, LTDC_L1CFBLR + lofs,
632 			LXCFBLR_CFBLL | LXCFBLR_CFBP, val);
633 
634 	/* Specifies the constant alpha value */
635 	val = CONSTA_MAX;
636 	reg_update_bits(ldev->regs, LTDC_L1CACR + lofs, LXCACR_CONSTA, val);
637 
638 	/* Specifies the blending factors */
639 	val = BF1_PAXCA | BF2_1PAXCA;
640 	reg_update_bits(ldev->regs, LTDC_L1BFCR + lofs,
641 			LXBFCR_BF2 | LXBFCR_BF1, val);
642 
643 	/* Configures the frame buffer line number */
644 	val = y1 - y0 + 1;
645 	reg_update_bits(ldev->regs, LTDC_L1CFBLNR + lofs, LXCFBLNR_CFBLN, val);
646 
647 	/* Sets the FB address */
648 	paddr = (u32)drm_fb_cma_get_gem_addr(fb, state, 0);
649 
650 	DRM_DEBUG_DRIVER("fb: phys 0x%08x", paddr);
651 	reg_write(ldev->regs, LTDC_L1CFBAR + lofs, paddr);
652 
653 	/* Enable layer and CLUT if needed */
654 	val = fb->format->format == DRM_FORMAT_C8 ? LXCR_CLUTEN : 0;
655 	val |= LXCR_LEN;
656 	reg_update_bits(ldev->regs, LTDC_L1CR + lofs,
657 			LXCR_LEN | LXCR_CLUTEN, val);
658 
659 	mutex_lock(&ldev->err_lock);
660 	if (ldev->error_status & ISR_FUIF) {
661 		DRM_DEBUG_DRIVER("Fifo underrun\n");
662 		ldev->error_status &= ~ISR_FUIF;
663 	}
664 	if (ldev->error_status & ISR_TERRIF) {
665 		DRM_DEBUG_DRIVER("Transfer error\n");
666 		ldev->error_status &= ~ISR_TERRIF;
667 	}
668 	mutex_unlock(&ldev->err_lock);
669 }
670 
671 static void ltdc_plane_atomic_disable(struct drm_plane *plane,
672 				      struct drm_plane_state *oldstate)
673 {
674 	struct ltdc_device *ldev = plane_to_ltdc(plane);
675 	u32 lofs = plane->index * LAY_OFS;
676 
677 	/* disable layer */
678 	reg_clear(ldev->regs, LTDC_L1CR + lofs, LXCR_LEN);
679 
680 	DRM_DEBUG_DRIVER("CRTC:%d plane:%d\n",
681 			 oldstate->crtc->base.id, plane->base.id);
682 }
683 
684 static const struct drm_plane_funcs ltdc_plane_funcs = {
685 	.update_plane = drm_atomic_helper_update_plane,
686 	.disable_plane = drm_atomic_helper_disable_plane,
687 	.destroy = drm_plane_cleanup,
688 	.reset = drm_atomic_helper_plane_reset,
689 	.atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
690 	.atomic_destroy_state = drm_atomic_helper_plane_destroy_state,
691 };
692 
693 static const struct drm_plane_helper_funcs ltdc_plane_helper_funcs = {
694 	.atomic_check = ltdc_plane_atomic_check,
695 	.atomic_update = ltdc_plane_atomic_update,
696 	.atomic_disable = ltdc_plane_atomic_disable,
697 };
698 
699 static struct drm_plane *ltdc_plane_create(struct drm_device *ddev,
700 					   enum drm_plane_type type)
701 {
702 	unsigned long possible_crtcs = CRTC_MASK;
703 	struct ltdc_device *ldev = ddev->dev_private;
704 	struct device *dev = ddev->dev;
705 	struct drm_plane *plane;
706 	unsigned int i, nb_fmt = 0;
707 	u32 formats[NB_PF];
708 	u32 drm_fmt;
709 	int ret;
710 
711 	/* Get supported pixel formats */
712 	for (i = 0; i < NB_PF; i++) {
713 		drm_fmt = to_drm_pixelformat(ldev->caps.pix_fmt_hw[i]);
714 		if (!drm_fmt)
715 			continue;
716 		formats[nb_fmt++] = drm_fmt;
717 	}
718 
719 	plane = devm_kzalloc(dev, sizeof(*plane), GFP_KERNEL);
720 	if (!plane)
721 		return 0;
722 
723 	ret = drm_universal_plane_init(ddev, plane, possible_crtcs,
724 				       &ltdc_plane_funcs, formats, nb_fmt,
725 				       NULL, type, NULL);
726 	if (ret < 0)
727 		return 0;
728 
729 	drm_plane_helper_add(plane, &ltdc_plane_helper_funcs);
730 
731 	DRM_DEBUG_DRIVER("plane:%d created\n", plane->base.id);
732 
733 	return plane;
734 }
735 
736 static void ltdc_plane_destroy_all(struct drm_device *ddev)
737 {
738 	struct drm_plane *plane, *plane_temp;
739 
740 	list_for_each_entry_safe(plane, plane_temp,
741 				 &ddev->mode_config.plane_list, head)
742 		drm_plane_cleanup(plane);
743 }
744 
745 static int ltdc_crtc_init(struct drm_device *ddev, struct drm_crtc *crtc)
746 {
747 	struct ltdc_device *ldev = ddev->dev_private;
748 	struct drm_plane *primary, *overlay;
749 	unsigned int i;
750 	int ret;
751 
752 	primary = ltdc_plane_create(ddev, DRM_PLANE_TYPE_PRIMARY);
753 	if (!primary) {
754 		DRM_ERROR("Can not create primary plane\n");
755 		return -EINVAL;
756 	}
757 
758 	ret = drm_crtc_init_with_planes(ddev, crtc, primary, NULL,
759 					&ltdc_crtc_funcs, NULL);
760 	if (ret) {
761 		DRM_ERROR("Can not initialize CRTC\n");
762 		goto cleanup;
763 	}
764 
765 	drm_crtc_helper_add(crtc, &ltdc_crtc_helper_funcs);
766 
767 	DRM_DEBUG_DRIVER("CRTC:%d created\n", crtc->base.id);
768 
769 	/* Add planes. Note : the first layer is used by primary plane */
770 	for (i = 1; i < ldev->caps.nb_layers; i++) {
771 		overlay = ltdc_plane_create(ddev, DRM_PLANE_TYPE_OVERLAY);
772 		if (!overlay) {
773 			ret = -ENOMEM;
774 			DRM_ERROR("Can not create overlay plane %d\n", i);
775 			goto cleanup;
776 		}
777 	}
778 
779 	return 0;
780 
781 cleanup:
782 	ltdc_plane_destroy_all(ddev);
783 	return ret;
784 }
785 
786 /*
787  * DRM_ENCODER
788  */
789 
790 static const struct drm_encoder_funcs ltdc_encoder_funcs = {
791 	.destroy = drm_encoder_cleanup,
792 };
793 
794 static int ltdc_encoder_init(struct drm_device *ddev)
795 {
796 	struct ltdc_device *ldev = ddev->dev_private;
797 	struct drm_encoder *encoder;
798 	int ret;
799 
800 	encoder = devm_kzalloc(ddev->dev, sizeof(*encoder), GFP_KERNEL);
801 	if (!encoder)
802 		return -ENOMEM;
803 
804 	encoder->possible_crtcs = CRTC_MASK;
805 	encoder->possible_clones = 0;	/* No cloning support */
806 
807 	drm_encoder_init(ddev, encoder, &ltdc_encoder_funcs,
808 			 DRM_MODE_ENCODER_DPI, NULL);
809 
810 	ret = drm_bridge_attach(encoder, ldev->bridge, NULL);
811 	if (ret) {
812 		drm_encoder_cleanup(encoder);
813 		return -EINVAL;
814 	}
815 
816 	DRM_DEBUG_DRIVER("Bridge encoder:%d created\n", encoder->base.id);
817 
818 	return 0;
819 }
820 
821 static int ltdc_get_caps(struct drm_device *ddev)
822 {
823 	struct ltdc_device *ldev = ddev->dev_private;
824 	u32 bus_width_log2, lcr, gc2r;
825 
826 	/* at least 1 layer must be managed */
827 	lcr = reg_read(ldev->regs, LTDC_LCR);
828 
829 	ldev->caps.nb_layers = max_t(int, lcr, 1);
830 
831 	/* set data bus width */
832 	gc2r = reg_read(ldev->regs, LTDC_GC2R);
833 	bus_width_log2 = (gc2r & GC2R_BW) >> 4;
834 	ldev->caps.bus_width = 8 << bus_width_log2;
835 	ldev->caps.hw_version = reg_read(ldev->regs, LTDC_IDR);
836 
837 	switch (ldev->caps.hw_version) {
838 	case HWVER_10200:
839 	case HWVER_10300:
840 		ldev->caps.reg_ofs = REG_OFS_NONE;
841 		ldev->caps.pix_fmt_hw = ltdc_pix_fmt_a0;
842 		break;
843 	case HWVER_20101:
844 		ldev->caps.reg_ofs = REG_OFS_4;
845 		ldev->caps.pix_fmt_hw = ltdc_pix_fmt_a1;
846 		break;
847 	default:
848 		return -ENODEV;
849 	}
850 
851 	return 0;
852 }
853 
854 int ltdc_load(struct drm_device *ddev)
855 {
856 	struct platform_device *pdev = to_platform_device(ddev->dev);
857 	struct ltdc_device *ldev = ddev->dev_private;
858 	struct device *dev = ddev->dev;
859 	struct device_node *np = dev->of_node;
860 	struct drm_bridge *bridge;
861 	struct drm_panel *panel;
862 	struct drm_crtc *crtc;
863 	struct reset_control *rstc;
864 	struct resource *res;
865 	int irq, ret, i;
866 
867 	DRM_DEBUG_DRIVER("\n");
868 
869 	ret = drm_of_find_panel_or_bridge(np, 0, 0, &panel, &bridge);
870 	if (ret)
871 		return ret;
872 
873 	rstc = devm_reset_control_get_exclusive(dev, NULL);
874 
875 	mutex_init(&ldev->err_lock);
876 
877 	ldev->pixel_clk = devm_clk_get(dev, "lcd");
878 	if (IS_ERR(ldev->pixel_clk)) {
879 		DRM_ERROR("Unable to get lcd clock\n");
880 		return -ENODEV;
881 	}
882 
883 	if (clk_prepare_enable(ldev->pixel_clk)) {
884 		DRM_ERROR("Unable to prepare pixel clock\n");
885 		return -ENODEV;
886 	}
887 
888 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
889 	if (!res) {
890 		DRM_ERROR("Unable to get resource\n");
891 		ret = -ENODEV;
892 		goto err;
893 	}
894 
895 	ldev->regs = devm_ioremap_resource(dev, res);
896 	if (IS_ERR(ldev->regs)) {
897 		DRM_ERROR("Unable to get ltdc registers\n");
898 		ret = PTR_ERR(ldev->regs);
899 		goto err;
900 	}
901 
902 	for (i = 0; i < MAX_IRQ; i++) {
903 		irq = platform_get_irq(pdev, i);
904 		if (irq < 0)
905 			continue;
906 
907 		ret = devm_request_threaded_irq(dev, irq, ltdc_irq,
908 						ltdc_irq_thread, IRQF_ONESHOT,
909 						dev_name(dev), ddev);
910 		if (ret) {
911 			DRM_ERROR("Failed to register LTDC interrupt\n");
912 			goto err;
913 		}
914 	}
915 
916 	if (!IS_ERR(rstc))
917 		reset_control_deassert(rstc);
918 
919 	/* Disable interrupts */
920 	reg_clear(ldev->regs, LTDC_IER,
921 		  IER_LIE | IER_RRIE | IER_FUIE | IER_TERRIE);
922 
923 	ret = ltdc_get_caps(ddev);
924 	if (ret) {
925 		DRM_ERROR("hardware identifier (0x%08x) not supported!\n",
926 			  ldev->caps.hw_version);
927 		goto err;
928 	}
929 
930 	DRM_INFO("ltdc hw version 0x%08x - ready\n", ldev->caps.hw_version);
931 
932 	if (panel) {
933 		bridge = drm_panel_bridge_add(panel, DRM_MODE_CONNECTOR_DPI);
934 		if (IS_ERR(bridge)) {
935 			DRM_ERROR("Failed to create panel-bridge\n");
936 			ret = PTR_ERR(bridge);
937 			goto err;
938 		}
939 		ldev->is_panel_bridge = true;
940 	}
941 
942 	ldev->bridge = bridge;
943 
944 	ret = ltdc_encoder_init(ddev);
945 	if (ret) {
946 		DRM_ERROR("Failed to init encoder\n");
947 		goto err;
948 	}
949 
950 	crtc = devm_kzalloc(dev, sizeof(*crtc), GFP_KERNEL);
951 	if (!crtc) {
952 		DRM_ERROR("Failed to allocate crtc\n");
953 		ret = -ENOMEM;
954 		goto err;
955 	}
956 
957 	ret = ltdc_crtc_init(ddev, crtc);
958 	if (ret) {
959 		DRM_ERROR("Failed to init crtc\n");
960 		goto err;
961 	}
962 
963 	ret = drm_vblank_init(ddev, NB_CRTC);
964 	if (ret) {
965 		DRM_ERROR("Failed calling drm_vblank_init()\n");
966 		goto err;
967 	}
968 
969 	/* Allow usage of vblank without having to call drm_irq_install */
970 	ddev->irq_enabled = 1;
971 
972 	return 0;
973 
974 err:
975 	if (ldev->is_panel_bridge)
976 		drm_panel_bridge_remove(bridge);
977 
978 	clk_disable_unprepare(ldev->pixel_clk);
979 
980 	return ret;
981 }
982 
983 void ltdc_unload(struct drm_device *ddev)
984 {
985 	struct ltdc_device *ldev = ddev->dev_private;
986 
987 	DRM_DEBUG_DRIVER("\n");
988 
989 	if (ldev->is_panel_bridge)
990 		drm_panel_bridge_remove(ldev->bridge);
991 
992 	clk_disable_unprepare(ldev->pixel_clk);
993 }
994 
995 MODULE_AUTHOR("Philippe Cornu <philippe.cornu@st.com>");
996 MODULE_AUTHOR("Yannick Fertre <yannick.fertre@st.com>");
997 MODULE_AUTHOR("Fabien Dessenne <fabien.dessenne@st.com>");
998 MODULE_AUTHOR("Mickael Reulier <mickael.reulier@st.com>");
999 MODULE_DESCRIPTION("STMicroelectronics ST DRM LTDC driver");
1000 MODULE_LICENSE("GPL v2");
1001