1 // SPDX-License-Identifier: GPL-2.0-only
2 
3 /*
4  * Versatile family (ARM reference designs) handling for the PL11x.
5  * This is based on code and know-how in the previous frame buffer
6  * driver in drivers/video/fbdev/amba-clcd.c:
7  * Copyright (C) 2001 ARM Limited, by David A Rusling
8  * Updated to 2.5 by Deep Blue Solutions Ltd.
9  * Major contributions and discoveries by Russell King.
10  */
11 
12 #include <linux/bitops.h>
13 #include <linux/device.h>
14 #include <linux/mfd/syscon.h>
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/of_platform.h>
18 #include <linux/platform_device.h>
19 #include <linux/regmap.h>
20 #include <linux/vexpress.h>
21 
22 #include <drm/drm_fourcc.h>
23 
24 #include "pl111_versatile.h"
25 #include "pl111_drm.h"
26 
27 static struct regmap *versatile_syscon_map;
28 
29 /*
30  * We detect the different syscon types from the compatible strings.
31  */
32 enum versatile_clcd {
33 	INTEGRATOR_IMPD1,
34 	INTEGRATOR_CLCD_CM,
35 	VERSATILE_CLCD,
36 	REALVIEW_CLCD_EB,
37 	REALVIEW_CLCD_PB1176,
38 	REALVIEW_CLCD_PB11MP,
39 	REALVIEW_CLCD_PBA8,
40 	REALVIEW_CLCD_PBX,
41 	VEXPRESS_CLCD_V2M,
42 };
43 
44 static const struct of_device_id versatile_clcd_of_match[] = {
45 	{
46 		.compatible = "arm,core-module-integrator",
47 		.data = (void *)INTEGRATOR_CLCD_CM,
48 	},
49 	{
50 		.compatible = "arm,versatile-sysreg",
51 		.data = (void *)VERSATILE_CLCD,
52 	},
53 	{
54 		.compatible = "arm,realview-eb-syscon",
55 		.data = (void *)REALVIEW_CLCD_EB,
56 	},
57 	{
58 		.compatible = "arm,realview-pb1176-syscon",
59 		.data = (void *)REALVIEW_CLCD_PB1176,
60 	},
61 	{
62 		.compatible = "arm,realview-pb11mp-syscon",
63 		.data = (void *)REALVIEW_CLCD_PB11MP,
64 	},
65 	{
66 		.compatible = "arm,realview-pba8-syscon",
67 		.data = (void *)REALVIEW_CLCD_PBA8,
68 	},
69 	{
70 		.compatible = "arm,realview-pbx-syscon",
71 		.data = (void *)REALVIEW_CLCD_PBX,
72 	},
73 	{
74 		.compatible = "arm,vexpress-muxfpga",
75 		.data = (void *)VEXPRESS_CLCD_V2M,
76 	},
77 	{},
78 };
79 
80 static const struct of_device_id impd1_clcd_of_match[] = {
81 	{
82 		.compatible = "arm,im-pd1-syscon",
83 		.data = (void *)INTEGRATOR_IMPD1,
84 	},
85 	{},
86 };
87 
88 /*
89  * Core module CLCD control on the Integrator/CP, bits
90  * 8 thru 19 of the CM_CONTROL register controls a bunch
91  * of CLCD settings.
92  */
93 #define INTEGRATOR_HDR_CTRL_OFFSET	0x0C
94 #define INTEGRATOR_CLCD_LCDBIASEN	BIT(8)
95 #define INTEGRATOR_CLCD_LCDBIASUP	BIT(9)
96 #define INTEGRATOR_CLCD_LCDBIASDN	BIT(10)
97 /* Bits 11,12,13 controls the LCD or VGA bridge type */
98 #define INTEGRATOR_CLCD_LCDMUX_LCD24	BIT(11)
99 #define INTEGRATOR_CLCD_LCDMUX_SHARP	(BIT(11)|BIT(12))
100 #define INTEGRATOR_CLCD_LCDMUX_VGA555	BIT(13)
101 #define INTEGRATOR_CLCD_LCDMUX_VGA24	(BIT(11)|BIT(12)|BIT(13))
102 #define INTEGRATOR_CLCD_LCD0_EN		BIT(14)
103 #define INTEGRATOR_CLCD_LCD1_EN		BIT(15)
104 /* R/L flip on Sharp */
105 #define INTEGRATOR_CLCD_LCD_STATIC1	BIT(16)
106 /* U/D flip on Sharp */
107 #define INTEGRATOR_CLCD_LCD_STATIC2	BIT(17)
108 /* No connection on Sharp */
109 #define INTEGRATOR_CLCD_LCD_STATIC	BIT(18)
110 /* 0 = 24bit VGA, 1 = 18bit VGA */
111 #define INTEGRATOR_CLCD_LCD_N24BITEN	BIT(19)
112 
113 #define INTEGRATOR_CLCD_MASK		GENMASK(19, 8)
114 
115 static void pl111_integrator_enable(struct drm_device *drm, u32 format)
116 {
117 	u32 val;
118 
119 	dev_info(drm->dev, "enable Integrator CLCD connectors\n");
120 
121 	/* FIXME: really needed? */
122 	val = INTEGRATOR_CLCD_LCD_STATIC1 | INTEGRATOR_CLCD_LCD_STATIC2 |
123 		INTEGRATOR_CLCD_LCD0_EN | INTEGRATOR_CLCD_LCD1_EN;
124 
125 	switch (format) {
126 	case DRM_FORMAT_XBGR8888:
127 	case DRM_FORMAT_XRGB8888:
128 		/* 24bit formats */
129 		val |= INTEGRATOR_CLCD_LCDMUX_VGA24;
130 		break;
131 	case DRM_FORMAT_XBGR1555:
132 	case DRM_FORMAT_XRGB1555:
133 		/* Pseudocolor, RGB555, BGR555 */
134 		val |= INTEGRATOR_CLCD_LCDMUX_VGA555;
135 		break;
136 	default:
137 		dev_err(drm->dev, "unhandled format on Integrator 0x%08x\n",
138 			format);
139 		break;
140 	}
141 
142 	regmap_update_bits(versatile_syscon_map,
143 			   INTEGRATOR_HDR_CTRL_OFFSET,
144 			   INTEGRATOR_CLCD_MASK,
145 			   val);
146 }
147 
148 #define IMPD1_CTRL_OFFSET	0x18
149 #define IMPD1_CTRL_DISP_LCD	(0 << 0)
150 #define IMPD1_CTRL_DISP_VGA	(1 << 0)
151 #define IMPD1_CTRL_DISP_LCD1	(2 << 0)
152 #define IMPD1_CTRL_DISP_ENABLE	(1 << 2)
153 #define IMPD1_CTRL_DISP_MASK	(7 << 0)
154 
155 static void pl111_impd1_enable(struct drm_device *drm, u32 format)
156 {
157 	u32 val;
158 
159 	dev_info(drm->dev, "enable IM-PD1 CLCD connectors\n");
160 	val = IMPD1_CTRL_DISP_VGA | IMPD1_CTRL_DISP_ENABLE;
161 
162 	regmap_update_bits(versatile_syscon_map,
163 			   IMPD1_CTRL_OFFSET,
164 			   IMPD1_CTRL_DISP_MASK,
165 			   val);
166 }
167 
168 static void pl111_impd1_disable(struct drm_device *drm)
169 {
170 	dev_info(drm->dev, "disable IM-PD1 CLCD connectors\n");
171 
172 	regmap_update_bits(versatile_syscon_map,
173 			   IMPD1_CTRL_OFFSET,
174 			   IMPD1_CTRL_DISP_MASK,
175 			   0);
176 }
177 
178 /*
179  * This configuration register in the Versatile and RealView
180  * family is uniformly present but appears more and more
181  * unutilized starting with the RealView series.
182  */
183 #define SYS_CLCD			0x50
184 #define SYS_CLCD_MODE_MASK		(BIT(0)|BIT(1))
185 #define SYS_CLCD_MODE_888		0
186 #define SYS_CLCD_MODE_5551		BIT(0)
187 #define SYS_CLCD_MODE_565_R_LSB		BIT(1)
188 #define SYS_CLCD_MODE_565_B_LSB		(BIT(0)|BIT(1))
189 #define SYS_CLCD_CONNECTOR_MASK		(BIT(2)|BIT(3)|BIT(4)|BIT(5))
190 #define SYS_CLCD_NLCDIOON		BIT(2)
191 #define SYS_CLCD_VDDPOSSWITCH		BIT(3)
192 #define SYS_CLCD_PWR3V5SWITCH		BIT(4)
193 #define SYS_CLCD_VDDNEGSWITCH		BIT(5)
194 
195 static void pl111_versatile_disable(struct drm_device *drm)
196 {
197 	dev_info(drm->dev, "disable Versatile CLCD connectors\n");
198 	regmap_update_bits(versatile_syscon_map,
199 			   SYS_CLCD,
200 			   SYS_CLCD_CONNECTOR_MASK,
201 			   0);
202 }
203 
204 static void pl111_versatile_enable(struct drm_device *drm, u32 format)
205 {
206 	u32 val = 0;
207 
208 	dev_info(drm->dev, "enable Versatile CLCD connectors\n");
209 
210 	switch (format) {
211 	case DRM_FORMAT_ABGR8888:
212 	case DRM_FORMAT_XBGR8888:
213 	case DRM_FORMAT_ARGB8888:
214 	case DRM_FORMAT_XRGB8888:
215 		val |= SYS_CLCD_MODE_888;
216 		break;
217 	case DRM_FORMAT_BGR565:
218 		val |= SYS_CLCD_MODE_565_R_LSB;
219 		break;
220 	case DRM_FORMAT_RGB565:
221 		val |= SYS_CLCD_MODE_565_B_LSB;
222 		break;
223 	case DRM_FORMAT_ABGR1555:
224 	case DRM_FORMAT_XBGR1555:
225 	case DRM_FORMAT_ARGB1555:
226 	case DRM_FORMAT_XRGB1555:
227 		val |= SYS_CLCD_MODE_5551;
228 		break;
229 	default:
230 		dev_err(drm->dev, "unhandled format on Versatile 0x%08x\n",
231 			format);
232 		break;
233 	}
234 
235 	/* Set up the MUX */
236 	regmap_update_bits(versatile_syscon_map,
237 			   SYS_CLCD,
238 			   SYS_CLCD_MODE_MASK,
239 			   val);
240 
241 	/* Then enable the display */
242 	regmap_update_bits(versatile_syscon_map,
243 			   SYS_CLCD,
244 			   SYS_CLCD_CONNECTOR_MASK,
245 			   SYS_CLCD_NLCDIOON | SYS_CLCD_PWR3V5SWITCH);
246 }
247 
248 static void pl111_realview_clcd_disable(struct drm_device *drm)
249 {
250 	dev_info(drm->dev, "disable RealView CLCD connectors\n");
251 	regmap_update_bits(versatile_syscon_map,
252 			   SYS_CLCD,
253 			   SYS_CLCD_CONNECTOR_MASK,
254 			   0);
255 }
256 
257 static void pl111_realview_clcd_enable(struct drm_device *drm, u32 format)
258 {
259 	dev_info(drm->dev, "enable RealView CLCD connectors\n");
260 	regmap_update_bits(versatile_syscon_map,
261 			   SYS_CLCD,
262 			   SYS_CLCD_CONNECTOR_MASK,
263 			   SYS_CLCD_NLCDIOON | SYS_CLCD_PWR3V5SWITCH);
264 }
265 
266 /* PL110 pixel formats for Integrator, vanilla PL110 */
267 static const u32 pl110_integrator_pixel_formats[] = {
268 	DRM_FORMAT_ABGR8888,
269 	DRM_FORMAT_XBGR8888,
270 	DRM_FORMAT_ARGB8888,
271 	DRM_FORMAT_XRGB8888,
272 	DRM_FORMAT_ABGR1555,
273 	DRM_FORMAT_XBGR1555,
274 	DRM_FORMAT_ARGB1555,
275 	DRM_FORMAT_XRGB1555,
276 };
277 
278 /* Extended PL110 pixel formats for Integrator and Versatile */
279 static const u32 pl110_versatile_pixel_formats[] = {
280 	DRM_FORMAT_ABGR8888,
281 	DRM_FORMAT_XBGR8888,
282 	DRM_FORMAT_ARGB8888,
283 	DRM_FORMAT_XRGB8888,
284 	DRM_FORMAT_BGR565, /* Uses external PLD */
285 	DRM_FORMAT_RGB565, /* Uses external PLD */
286 	DRM_FORMAT_ABGR1555,
287 	DRM_FORMAT_XBGR1555,
288 	DRM_FORMAT_ARGB1555,
289 	DRM_FORMAT_XRGB1555,
290 };
291 
292 static const u32 pl111_realview_pixel_formats[] = {
293 	DRM_FORMAT_ABGR8888,
294 	DRM_FORMAT_XBGR8888,
295 	DRM_FORMAT_ARGB8888,
296 	DRM_FORMAT_XRGB8888,
297 	DRM_FORMAT_BGR565,
298 	DRM_FORMAT_RGB565,
299 	DRM_FORMAT_ABGR1555,
300 	DRM_FORMAT_XBGR1555,
301 	DRM_FORMAT_ARGB1555,
302 	DRM_FORMAT_XRGB1555,
303 	DRM_FORMAT_ABGR4444,
304 	DRM_FORMAT_XBGR4444,
305 	DRM_FORMAT_ARGB4444,
306 	DRM_FORMAT_XRGB4444,
307 };
308 
309 /*
310  * The Integrator variant is a PL110 with a bunch of broken, or not
311  * yet implemented features
312  */
313 static const struct pl111_variant_data pl110_integrator = {
314 	.name = "PL110 Integrator",
315 	.is_pl110 = true,
316 	.broken_clockdivider = true,
317 	.broken_vblank = true,
318 	.formats = pl110_integrator_pixel_formats,
319 	.nformats = ARRAY_SIZE(pl110_integrator_pixel_formats),
320 	.fb_depth = 16,
321 };
322 
323 /*
324  * The IM-PD1 variant is a PL110 with a bunch of broken, or not
325  * yet implemented features
326  */
327 static const struct pl111_variant_data pl110_impd1 = {
328 	.name = "PL110 IM-PD1",
329 	.is_pl110 = true,
330 	.broken_clockdivider = true,
331 	.broken_vblank = true,
332 	.formats = pl110_integrator_pixel_formats,
333 	.nformats = ARRAY_SIZE(pl110_integrator_pixel_formats),
334 	.fb_depth = 15,
335 };
336 
337 /*
338  * This is the in-between PL110 variant found in the ARM Versatile,
339  * supporting RGB565/BGR565
340  */
341 static const struct pl111_variant_data pl110_versatile = {
342 	.name = "PL110 Versatile",
343 	.is_pl110 = true,
344 	.external_bgr = true,
345 	.formats = pl110_versatile_pixel_formats,
346 	.nformats = ARRAY_SIZE(pl110_versatile_pixel_formats),
347 	.fb_depth = 16,
348 };
349 
350 /*
351  * RealView PL111 variant, the only real difference from the vanilla
352  * PL111 is that we select 16bpp framebuffer by default to be able
353  * to get 1024x768 without saturating the memory bus.
354  */
355 static const struct pl111_variant_data pl111_realview = {
356 	.name = "PL111 RealView",
357 	.formats = pl111_realview_pixel_formats,
358 	.nformats = ARRAY_SIZE(pl111_realview_pixel_formats),
359 	.fb_depth = 16,
360 };
361 
362 /*
363  * Versatile Express PL111 variant, again we just push the maximum
364  * BPP to 16 to be able to get 1024x768 without saturating the memory
365  * bus. The clockdivider also seems broken on the Versatile Express.
366  */
367 static const struct pl111_variant_data pl111_vexpress = {
368 	.name = "PL111 Versatile Express",
369 	.formats = pl111_realview_pixel_formats,
370 	.nformats = ARRAY_SIZE(pl111_realview_pixel_formats),
371 	.fb_depth = 16,
372 	.broken_clockdivider = true,
373 };
374 
375 #define VEXPRESS_FPGAMUX_MOTHERBOARD		0x00
376 #define VEXPRESS_FPGAMUX_DAUGHTERBOARD_1	0x01
377 #define VEXPRESS_FPGAMUX_DAUGHTERBOARD_2	0x02
378 
379 static int pl111_vexpress_clcd_init(struct device *dev, struct device_node *np,
380 				    struct pl111_drm_dev_private *priv)
381 {
382 	struct platform_device *pdev;
383 	struct device_node *root;
384 	struct device_node *child;
385 	struct device_node *ct_clcd = NULL;
386 	struct regmap *map;
387 	bool has_coretile_clcd = false;
388 	bool has_coretile_hdlcd = false;
389 	bool mux_motherboard = true;
390 	u32 val;
391 	int ret;
392 
393 	if (!IS_ENABLED(CONFIG_VEXPRESS_CONFIG))
394 		return -ENODEV;
395 
396 	/*
397 	 * Check if we have a CLCD or HDLCD on the core tile by checking if a
398 	 * CLCD or HDLCD is available in the root of the device tree.
399 	 */
400 	root = of_find_node_by_path("/");
401 	if (!root)
402 		return -EINVAL;
403 
404 	for_each_available_child_of_node(root, child) {
405 		if (of_device_is_compatible(child, "arm,pl111")) {
406 			has_coretile_clcd = true;
407 			ct_clcd = child;
408 			of_node_put(child);
409 			break;
410 		}
411 		if (of_device_is_compatible(child, "arm,hdlcd")) {
412 			has_coretile_hdlcd = true;
413 			of_node_put(child);
414 			break;
415 		}
416 	}
417 
418 	of_node_put(root);
419 
420 	/*
421 	 * If there is a coretile HDLCD and it has a driver,
422 	 * do not mux the CLCD on the motherboard to the DVI.
423 	 */
424 	if (has_coretile_hdlcd && IS_ENABLED(CONFIG_DRM_HDLCD))
425 		mux_motherboard = false;
426 
427 	/*
428 	 * On the Vexpress CA9 we let the CLCD on the coretile
429 	 * take precedence, so also in this case do not mux the
430 	 * motherboard to the DVI.
431 	 */
432 	if (has_coretile_clcd)
433 		mux_motherboard = false;
434 
435 	if (mux_motherboard) {
436 		dev_info(dev, "DVI muxed to motherboard CLCD\n");
437 		val = VEXPRESS_FPGAMUX_MOTHERBOARD;
438 	} else if (ct_clcd == dev->of_node) {
439 		dev_info(dev,
440 			 "DVI muxed to daughterboard 1 (core tile) CLCD\n");
441 		val = VEXPRESS_FPGAMUX_DAUGHTERBOARD_1;
442 	} else {
443 		dev_info(dev, "core tile graphics present\n");
444 		dev_info(dev, "this device will be deactivated\n");
445 		return -ENODEV;
446 	}
447 
448 	/* Call into deep Vexpress configuration API */
449 	pdev = of_find_device_by_node(np);
450 	if (!pdev) {
451 		dev_err(dev, "can't find the sysreg device, deferring\n");
452 		return -EPROBE_DEFER;
453 	}
454 
455 	map = devm_regmap_init_vexpress_config(&pdev->dev);
456 	if (IS_ERR(map)) {
457 		platform_device_put(pdev);
458 		return PTR_ERR(map);
459 	}
460 
461 	ret = regmap_write(map, 0, val);
462 	platform_device_put(pdev);
463 	if (ret) {
464 		dev_err(dev, "error setting DVI muxmode\n");
465 		return -ENODEV;
466 	}
467 
468 	priv->variant = &pl111_vexpress;
469 	dev_info(dev, "initializing Versatile Express PL111\n");
470 
471 	return 0;
472 }
473 
474 int pl111_versatile_init(struct device *dev, struct pl111_drm_dev_private *priv)
475 {
476 	const struct of_device_id *clcd_id;
477 	enum versatile_clcd versatile_clcd_type;
478 	struct device_node *np;
479 	struct regmap *map;
480 
481 	np = of_find_matching_node_and_match(NULL, versatile_clcd_of_match,
482 					     &clcd_id);
483 	if (!np) {
484 		/* Non-ARM reference designs, just bail out */
485 		return 0;
486 	}
487 
488 	versatile_clcd_type = (enum versatile_clcd)clcd_id->data;
489 
490 	/* Versatile Express special handling */
491 	if (versatile_clcd_type == VEXPRESS_CLCD_V2M) {
492 		int ret = pl111_vexpress_clcd_init(dev, np, priv);
493 		of_node_put(np);
494 		if (ret)
495 			dev_err(dev, "Versatile Express init failed - %d", ret);
496 		return ret;
497 	}
498 
499 	/*
500 	 * On the Integrator, check if we should use the IM-PD1 instead,
501 	 * if we find it, it will take precedence. This is on the Integrator/AP
502 	 * which only has this option for PL110 graphics.
503 	 */
504 	 if (versatile_clcd_type == INTEGRATOR_CLCD_CM) {
505 		np = of_find_matching_node_and_match(NULL, impd1_clcd_of_match,
506 						     &clcd_id);
507 		if (np)
508 			versatile_clcd_type = (enum versatile_clcd)clcd_id->data;
509 	}
510 
511 	map = syscon_node_to_regmap(np);
512 	of_node_put(np);
513 	if (IS_ERR(map)) {
514 		dev_err(dev, "no Versatile syscon regmap\n");
515 		return PTR_ERR(map);
516 	}
517 
518 	switch (versatile_clcd_type) {
519 	case INTEGRATOR_CLCD_CM:
520 		versatile_syscon_map = map;
521 		priv->variant = &pl110_integrator;
522 		priv->variant_display_enable = pl111_integrator_enable;
523 		dev_info(dev, "set up callbacks for Integrator PL110\n");
524 		break;
525 	case INTEGRATOR_IMPD1:
526 		versatile_syscon_map = map;
527 		priv->variant = &pl110_impd1;
528 		priv->variant_display_enable = pl111_impd1_enable;
529 		priv->variant_display_disable = pl111_impd1_disable;
530 		dev_info(dev, "set up callbacks for IM-PD1 PL110\n");
531 		break;
532 	case VERSATILE_CLCD:
533 		versatile_syscon_map = map;
534 		/* This can do RGB565 with external PLD */
535 		priv->variant = &pl110_versatile;
536 		priv->variant_display_enable = pl111_versatile_enable;
537 		priv->variant_display_disable = pl111_versatile_disable;
538 		/*
539 		 * The Versatile has a variant halfway between PL110
540 		 * and PL111 where these two registers have already been
541 		 * swapped.
542 		 */
543 		priv->ienb = CLCD_PL111_IENB;
544 		priv->ctrl = CLCD_PL111_CNTL;
545 		dev_info(dev, "set up callbacks for Versatile PL110\n");
546 		break;
547 	case REALVIEW_CLCD_EB:
548 	case REALVIEW_CLCD_PB1176:
549 	case REALVIEW_CLCD_PB11MP:
550 	case REALVIEW_CLCD_PBA8:
551 	case REALVIEW_CLCD_PBX:
552 		versatile_syscon_map = map;
553 		priv->variant = &pl111_realview;
554 		priv->variant_display_enable = pl111_realview_clcd_enable;
555 		priv->variant_display_disable = pl111_realview_clcd_disable;
556 		dev_info(dev, "set up callbacks for RealView PL111\n");
557 		break;
558 	default:
559 		dev_info(dev, "unknown Versatile system controller\n");
560 		break;
561 	}
562 
563 	return 0;
564 }
565 EXPORT_SYMBOL_GPL(pl111_versatile_init);
566