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
27static struct regmap *versatile_syscon_map;
28
29/*
30 * We detect the different syscon types from the compatible strings.
31 */
32enum 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
44static 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
80static 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
115static 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
155static 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
168static 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
195static 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
204static 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
248static 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
257static 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 */
267static 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 */
279static 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
292static 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 */
313static 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 */
327static 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 */
341static 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 */
355static 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 */
367static 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
379static 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
474int 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}
565EXPORT_SYMBOL_GPL(pl111_versatile_init);
566