xref: /linux/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c (revision 6f7e6393d1ce636bb7ec77a7fe7b77458fddf701)
1 // SPDX-License-Identifier: GPL-2.0+
2 
3 /*
4  * Copyright 2020 NXP
5  */
6 
7 #include <linux/bitfield.h>
8 #include <linux/clk.h>
9 #include <linux/delay.h>
10 #include <linux/io.h>
11 #include <linux/media-bus-format.h>
12 #include <linux/module.h>
13 #include <linux/of.h>
14 #include <linux/of_graph.h>
15 #include <linux/platform_device.h>
16 #include <linux/pm_runtime.h>
17 
18 #include <drm/drm_atomic_state_helper.h>
19 #include <drm/drm_bridge.h>
20 #include <drm/drm_print.h>
21 
22 #define PC_CTRL_REG			0x0
23 #define  PC_COMBINE_ENABLE		BIT(0)
24 #define  PC_DISP_BYPASS(n)		BIT(1 + 21 * (n))
25 #define  PC_DISP_HSYNC_POLARITY(n)	BIT(2 + 11 * (n))
26 #define  PC_DISP_HSYNC_POLARITY_POS(n)	DISP_HSYNC_POLARITY(n)
27 #define  PC_DISP_VSYNC_POLARITY(n)	BIT(3 + 11 * (n))
28 #define  PC_DISP_VSYNC_POLARITY_POS(n)	DISP_VSYNC_POLARITY(n)
29 #define  PC_DISP_DVALID_POLARITY(n)	BIT(4 + 11 * (n))
30 #define  PC_DISP_DVALID_POLARITY_POS(n)	DISP_DVALID_POLARITY(n)
31 #define  PC_VSYNC_MASK_ENABLE		BIT(5)
32 #define  PC_SKIP_MODE			BIT(6)
33 #define  PC_SKIP_NUMBER_MASK		GENMASK(12, 7)
34 #define  PC_SKIP_NUMBER(n)		FIELD_PREP(PC_SKIP_NUMBER_MASK, (n))
35 #define  PC_DISP0_PIX_DATA_FORMAT_MASK	GENMASK(18, 16)
36 #define  PC_DISP0_PIX_DATA_FORMAT(fmt)	\
37 				FIELD_PREP(PC_DISP0_PIX_DATA_FORMAT_MASK, (fmt))
38 #define  PC_DISP1_PIX_DATA_FORMAT_MASK	GENMASK(21, 19)
39 #define  PC_DISP1_PIX_DATA_FORMAT(fmt)	\
40 				FIELD_PREP(PC_DISP1_PIX_DATA_FORMAT_MASK, (fmt))
41 
42 #define PC_SW_RESET_REG			0x20
43 #define  PC_SW_RESET_N			BIT(0)
44 #define  PC_DISP_SW_RESET_N(n)		BIT(1 + (n))
45 #define  PC_FULL_RESET_N		(PC_SW_RESET_N |		\
46 					 PC_DISP_SW_RESET_N(0) |	\
47 					 PC_DISP_SW_RESET_N(1))
48 
49 #define PC_REG_SET			0x4
50 #define PC_REG_CLR			0x8
51 
52 #define DRIVER_NAME			"imx8qxp-pixel-combiner"
53 
54 enum imx8qxp_pc_pix_data_format {
55 	RGB,
56 	YUV444,
57 	YUV422,
58 	SPLIT_RGB,
59 };
60 
61 struct imx8qxp_pc_channel {
62 	struct drm_bridge bridge;
63 	struct drm_bridge *next_bridge;
64 	struct imx8qxp_pc *pc;
65 	unsigned int stream_id;
66 };
67 
68 struct imx8qxp_pc {
69 	struct device *dev;
70 	struct imx8qxp_pc_channel *ch[2];
71 	struct clk *clk_apb;
72 	void __iomem *base;
73 };
74 
75 static inline u32 imx8qxp_pc_read(struct imx8qxp_pc *pc, unsigned int offset)
76 {
77 	return readl(pc->base + offset);
78 }
79 
80 static inline void
81 imx8qxp_pc_write(struct imx8qxp_pc *pc, unsigned int offset, u32 value)
82 {
83 	writel(value, pc->base + offset);
84 }
85 
86 static inline void
87 imx8qxp_pc_write_set(struct imx8qxp_pc *pc, unsigned int offset, u32 value)
88 {
89 	imx8qxp_pc_write(pc, offset + PC_REG_SET, value);
90 }
91 
92 static inline void
93 imx8qxp_pc_write_clr(struct imx8qxp_pc *pc, unsigned int offset, u32 value)
94 {
95 	imx8qxp_pc_write(pc, offset + PC_REG_CLR, value);
96 }
97 
98 static enum drm_mode_status
99 imx8qxp_pc_bridge_mode_valid(struct drm_bridge *bridge,
100 			     const struct drm_display_info *info,
101 			     const struct drm_display_mode *mode)
102 {
103 	if (mode->hdisplay > 2560)
104 		return MODE_BAD_HVALUE;
105 
106 	return MODE_OK;
107 }
108 
109 static int imx8qxp_pc_bridge_attach(struct drm_bridge *bridge,
110 				    struct drm_encoder *encoder,
111 				    enum drm_bridge_attach_flags flags)
112 {
113 	struct imx8qxp_pc_channel *ch = bridge->driver_private;
114 	struct imx8qxp_pc *pc = ch->pc;
115 
116 	if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)) {
117 		DRM_DEV_ERROR(pc->dev,
118 			      "do not support creating a drm_connector\n");
119 		return -EINVAL;
120 	}
121 
122 	return drm_bridge_attach(encoder,
123 				 ch->next_bridge, bridge,
124 				 DRM_BRIDGE_ATTACH_NO_CONNECTOR);
125 }
126 
127 static void
128 imx8qxp_pc_bridge_mode_set(struct drm_bridge *bridge,
129 			   const struct drm_display_mode *mode,
130 			   const struct drm_display_mode *adjusted_mode)
131 {
132 	struct imx8qxp_pc_channel *ch = bridge->driver_private;
133 	struct imx8qxp_pc *pc = ch->pc;
134 	u32 val;
135 	int ret;
136 
137 	ret = pm_runtime_get_sync(pc->dev);
138 	if (ret < 0)
139 		DRM_DEV_ERROR(pc->dev,
140 			      "failed to get runtime PM sync: %d\n", ret);
141 
142 	ret = clk_prepare_enable(pc->clk_apb);
143 	if (ret)
144 		DRM_DEV_ERROR(pc->dev, "%s: failed to enable apb clock: %d\n",
145 			      __func__,  ret);
146 
147 	/* HSYNC to pixel link is active low. */
148 	imx8qxp_pc_write_clr(pc, PC_CTRL_REG,
149 			     PC_DISP_HSYNC_POLARITY(ch->stream_id));
150 
151 	/* VSYNC to pixel link is active low. */
152 	imx8qxp_pc_write_clr(pc, PC_CTRL_REG,
153 			     PC_DISP_VSYNC_POLARITY(ch->stream_id));
154 
155 	/* Data enable to pixel link is active high. */
156 	imx8qxp_pc_write_set(pc, PC_CTRL_REG,
157 			     PC_DISP_DVALID_POLARITY(ch->stream_id));
158 
159 	/* Mask the first frame output which may be incomplete. */
160 	imx8qxp_pc_write_set(pc, PC_CTRL_REG, PC_VSYNC_MASK_ENABLE);
161 
162 	/* Only support RGB currently. */
163 	val = imx8qxp_pc_read(pc, PC_CTRL_REG);
164 	if (ch->stream_id == 0) {
165 		val &= ~PC_DISP0_PIX_DATA_FORMAT_MASK;
166 		val |= PC_DISP0_PIX_DATA_FORMAT(RGB);
167 	} else {
168 		val &= ~PC_DISP1_PIX_DATA_FORMAT_MASK;
169 		val |= PC_DISP1_PIX_DATA_FORMAT(RGB);
170 	}
171 	imx8qxp_pc_write(pc, PC_CTRL_REG, val);
172 
173 	/* Only support bypass mode currently. */
174 	imx8qxp_pc_write_set(pc, PC_CTRL_REG, PC_DISP_BYPASS(ch->stream_id));
175 
176 	clk_disable_unprepare(pc->clk_apb);
177 }
178 
179 static void imx8qxp_pc_bridge_atomic_disable(struct drm_bridge *bridge,
180 					     struct drm_atomic_state *state)
181 {
182 	struct imx8qxp_pc_channel *ch = bridge->driver_private;
183 	struct imx8qxp_pc *pc = ch->pc;
184 
185 	pm_runtime_put(pc->dev);
186 }
187 
188 static const u32 imx8qxp_pc_bus_output_fmts[] = {
189 	MEDIA_BUS_FMT_RGB888_1X36_CPADLO,
190 	MEDIA_BUS_FMT_RGB666_1X36_CPADLO,
191 };
192 
193 static bool imx8qxp_pc_bus_output_fmt_supported(u32 fmt)
194 {
195 	int i;
196 
197 	for (i = 0; i < ARRAY_SIZE(imx8qxp_pc_bus_output_fmts); i++) {
198 		if (imx8qxp_pc_bus_output_fmts[i] == fmt)
199 			return true;
200 	}
201 
202 	return false;
203 }
204 
205 static u32 *
206 imx8qxp_pc_bridge_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
207 					    struct drm_bridge_state *bridge_state,
208 					    struct drm_crtc_state *crtc_state,
209 					    struct drm_connector_state *conn_state,
210 					    u32 output_fmt,
211 					    unsigned int *num_input_fmts)
212 {
213 	u32 *input_fmts;
214 
215 	if (!imx8qxp_pc_bus_output_fmt_supported(output_fmt))
216 		return NULL;
217 
218 	*num_input_fmts = 1;
219 
220 	input_fmts = kmalloc(sizeof(*input_fmts), GFP_KERNEL);
221 	if (!input_fmts)
222 		return NULL;
223 
224 	switch (output_fmt) {
225 	case MEDIA_BUS_FMT_RGB888_1X36_CPADLO:
226 		input_fmts[0] = MEDIA_BUS_FMT_RGB888_1X30_CPADLO;
227 		break;
228 	case MEDIA_BUS_FMT_RGB666_1X36_CPADLO:
229 		input_fmts[0] = MEDIA_BUS_FMT_RGB666_1X30_CPADLO;
230 		break;
231 	default:
232 		kfree(input_fmts);
233 		input_fmts = NULL;
234 		break;
235 	}
236 
237 	return input_fmts;
238 }
239 
240 static u32 *
241 imx8qxp_pc_bridge_atomic_get_output_bus_fmts(struct drm_bridge *bridge,
242 					     struct drm_bridge_state *bridge_state,
243 					     struct drm_crtc_state *crtc_state,
244 					     struct drm_connector_state *conn_state,
245 					     unsigned int *num_output_fmts)
246 {
247 	*num_output_fmts = ARRAY_SIZE(imx8qxp_pc_bus_output_fmts);
248 	return kmemdup(imx8qxp_pc_bus_output_fmts,
249 			sizeof(imx8qxp_pc_bus_output_fmts), GFP_KERNEL);
250 }
251 
252 static const struct drm_bridge_funcs imx8qxp_pc_bridge_funcs = {
253 	.atomic_duplicate_state	= drm_atomic_helper_bridge_duplicate_state,
254 	.atomic_destroy_state	= drm_atomic_helper_bridge_destroy_state,
255 	.atomic_reset		= drm_atomic_helper_bridge_reset,
256 	.mode_valid		= imx8qxp_pc_bridge_mode_valid,
257 	.attach			= imx8qxp_pc_bridge_attach,
258 	.mode_set		= imx8qxp_pc_bridge_mode_set,
259 	.atomic_disable		= imx8qxp_pc_bridge_atomic_disable,
260 	.atomic_get_input_bus_fmts =
261 				imx8qxp_pc_bridge_atomic_get_input_bus_fmts,
262 	.atomic_get_output_bus_fmts =
263 				imx8qxp_pc_bridge_atomic_get_output_bus_fmts,
264 };
265 
266 static int imx8qxp_pc_bridge_probe(struct platform_device *pdev)
267 {
268 	struct imx8qxp_pc *pc;
269 	struct imx8qxp_pc_channel *ch;
270 	struct device *dev = &pdev->dev;
271 	struct device_node *np = dev->of_node;
272 	struct device_node *child, *remote;
273 	u32 i;
274 	int ret;
275 
276 	pc = devm_kzalloc(dev, sizeof(*pc), GFP_KERNEL);
277 	if (!pc)
278 		return -ENOMEM;
279 
280 	pc->base = devm_platform_ioremap_resource(pdev, 0);
281 	if (IS_ERR(pc->base))
282 		return PTR_ERR(pc->base);
283 
284 	pc->dev = dev;
285 
286 	pc->clk_apb = devm_clk_get(dev, "apb");
287 	if (IS_ERR(pc->clk_apb)) {
288 		ret = PTR_ERR(pc->clk_apb);
289 		if (ret != -EPROBE_DEFER)
290 			DRM_DEV_ERROR(dev, "failed to get apb clock: %d\n", ret);
291 		return ret;
292 	}
293 
294 	platform_set_drvdata(pdev, pc);
295 	pm_runtime_enable(dev);
296 
297 	for_each_available_child_of_node(np, child) {
298 		ret = of_property_read_u32(child, "reg", &i);
299 		if (ret || i > 1) {
300 			ret = -EINVAL;
301 			DRM_DEV_ERROR(dev,
302 				      "invalid channel(%u) node address\n", i);
303 			goto free_child;
304 		}
305 
306 		ch = devm_drm_bridge_alloc(dev, struct imx8qxp_pc_channel, bridge,
307 					   &imx8qxp_pc_bridge_funcs);
308 		if (IS_ERR(ch)) {
309 			ret = PTR_ERR(ch);
310 			goto free_child;
311 		}
312 
313 		pc->ch[i] = ch;
314 		ch->pc = pc;
315 		ch->stream_id = i;
316 
317 		remote = of_graph_get_remote_node(child, 1, 0);
318 		if (!remote) {
319 			ret = -ENODEV;
320 			DRM_DEV_ERROR(dev,
321 				      "channel%u failed to get port1's remote node: %d\n",
322 				      i, ret);
323 			goto free_child;
324 		}
325 
326 		ch->next_bridge = of_drm_find_bridge(remote);
327 		if (!ch->next_bridge) {
328 			of_node_put(remote);
329 			ret = -EPROBE_DEFER;
330 			DRM_DEV_DEBUG_DRIVER(dev,
331 					     "channel%u failed to find next bridge: %d\n",
332 					     i, ret);
333 			goto free_child;
334 		}
335 
336 		of_node_put(remote);
337 
338 		ch->bridge.driver_private = ch;
339 		ch->bridge.of_node = child;
340 
341 		drm_bridge_add(&ch->bridge);
342 	}
343 
344 	return 0;
345 
346 free_child:
347 	of_node_put(child);
348 
349 	if (i == 1 && pc->ch[0]->next_bridge)
350 		drm_bridge_remove(&pc->ch[0]->bridge);
351 
352 	pm_runtime_disable(dev);
353 	return ret;
354 }
355 
356 static void imx8qxp_pc_bridge_remove(struct platform_device *pdev)
357 {
358 	struct imx8qxp_pc *pc = platform_get_drvdata(pdev);
359 	struct imx8qxp_pc_channel *ch;
360 	int i;
361 
362 	for (i = 0; i < 2; i++) {
363 		ch = pc->ch[i];
364 
365 		if (ch)
366 			drm_bridge_remove(&ch->bridge);
367 	}
368 
369 	pm_runtime_disable(&pdev->dev);
370 }
371 
372 static int imx8qxp_pc_runtime_suspend(struct device *dev)
373 {
374 	struct platform_device *pdev = to_platform_device(dev);
375 	struct imx8qxp_pc *pc = platform_get_drvdata(pdev);
376 	int ret;
377 
378 	ret = clk_prepare_enable(pc->clk_apb);
379 	if (ret)
380 		DRM_DEV_ERROR(pc->dev, "%s: failed to enable apb clock: %d\n",
381 			      __func__,  ret);
382 
383 	/* Disable pixel combiner by full reset. */
384 	imx8qxp_pc_write_clr(pc, PC_SW_RESET_REG, PC_FULL_RESET_N);
385 
386 	clk_disable_unprepare(pc->clk_apb);
387 
388 	/* Ensure the reset takes effect. */
389 	usleep_range(10, 20);
390 
391 	return ret;
392 }
393 
394 static int imx8qxp_pc_runtime_resume(struct device *dev)
395 {
396 	struct platform_device *pdev = to_platform_device(dev);
397 	struct imx8qxp_pc *pc = platform_get_drvdata(pdev);
398 	int ret;
399 
400 	ret = clk_prepare_enable(pc->clk_apb);
401 	if (ret) {
402 		DRM_DEV_ERROR(pc->dev, "%s: failed to enable apb clock: %d\n",
403 			      __func__, ret);
404 		return ret;
405 	}
406 
407 	/* out of reset */
408 	imx8qxp_pc_write_set(pc, PC_SW_RESET_REG, PC_FULL_RESET_N);
409 
410 	clk_disable_unprepare(pc->clk_apb);
411 
412 	return ret;
413 }
414 
415 static const struct dev_pm_ops imx8qxp_pc_pm_ops = {
416 	RUNTIME_PM_OPS(imx8qxp_pc_runtime_suspend, imx8qxp_pc_runtime_resume, NULL)
417 };
418 
419 static const struct of_device_id imx8qxp_pc_dt_ids[] = {
420 	{ .compatible = "fsl,imx8qm-pixel-combiner", },
421 	{ .compatible = "fsl,imx8qxp-pixel-combiner", },
422 	{ /* sentinel */ }
423 };
424 MODULE_DEVICE_TABLE(of, imx8qxp_pc_dt_ids);
425 
426 static struct platform_driver imx8qxp_pc_bridge_driver = {
427 	.probe	= imx8qxp_pc_bridge_probe,
428 	.remove = imx8qxp_pc_bridge_remove,
429 	.driver	= {
430 		.pm = pm_ptr(&imx8qxp_pc_pm_ops),
431 		.name = DRIVER_NAME,
432 		.of_match_table = imx8qxp_pc_dt_ids,
433 	},
434 };
435 module_platform_driver(imx8qxp_pc_bridge_driver);
436 
437 MODULE_DESCRIPTION("i.MX8QM/QXP pixel combiner bridge driver");
438 MODULE_AUTHOR("Liu Ying <victor.liu@nxp.com>");
439 MODULE_LICENSE("GPL v2");
440 MODULE_ALIAS("platform:" DRIVER_NAME);
441