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 bool is_available;
67 };
68
69 struct imx8qxp_pc {
70 struct device *dev;
71 struct imx8qxp_pc_channel ch[2];
72 struct clk *clk_apb;
73 void __iomem *base;
74 };
75
imx8qxp_pc_read(struct imx8qxp_pc * pc,unsigned int offset)76 static inline u32 imx8qxp_pc_read(struct imx8qxp_pc *pc, unsigned int offset)
77 {
78 return readl(pc->base + offset);
79 }
80
81 static inline void
imx8qxp_pc_write(struct imx8qxp_pc * pc,unsigned int offset,u32 value)82 imx8qxp_pc_write(struct imx8qxp_pc *pc, unsigned int offset, u32 value)
83 {
84 writel(value, pc->base + offset);
85 }
86
87 static inline void
imx8qxp_pc_write_set(struct imx8qxp_pc * pc,unsigned int offset,u32 value)88 imx8qxp_pc_write_set(struct imx8qxp_pc *pc, unsigned int offset, u32 value)
89 {
90 imx8qxp_pc_write(pc, offset + PC_REG_SET, value);
91 }
92
93 static inline void
imx8qxp_pc_write_clr(struct imx8qxp_pc * pc,unsigned int offset,u32 value)94 imx8qxp_pc_write_clr(struct imx8qxp_pc *pc, unsigned int offset, u32 value)
95 {
96 imx8qxp_pc_write(pc, offset + PC_REG_CLR, value);
97 }
98
99 static enum drm_mode_status
imx8qxp_pc_bridge_mode_valid(struct drm_bridge * bridge,const struct drm_display_info * info,const struct drm_display_mode * mode)100 imx8qxp_pc_bridge_mode_valid(struct drm_bridge *bridge,
101 const struct drm_display_info *info,
102 const struct drm_display_mode *mode)
103 {
104 if (mode->hdisplay > 2560)
105 return MODE_BAD_HVALUE;
106
107 return MODE_OK;
108 }
109
imx8qxp_pc_bridge_attach(struct drm_bridge * bridge,enum drm_bridge_attach_flags flags)110 static int imx8qxp_pc_bridge_attach(struct drm_bridge *bridge,
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 if (!bridge->encoder) {
123 DRM_DEV_ERROR(pc->dev, "missing encoder\n");
124 return -ENODEV;
125 }
126
127 return drm_bridge_attach(bridge->encoder,
128 ch->next_bridge, bridge,
129 DRM_BRIDGE_ATTACH_NO_CONNECTOR);
130 }
131
132 static void
imx8qxp_pc_bridge_mode_set(struct drm_bridge * bridge,const struct drm_display_mode * mode,const struct drm_display_mode * adjusted_mode)133 imx8qxp_pc_bridge_mode_set(struct drm_bridge *bridge,
134 const struct drm_display_mode *mode,
135 const struct drm_display_mode *adjusted_mode)
136 {
137 struct imx8qxp_pc_channel *ch = bridge->driver_private;
138 struct imx8qxp_pc *pc = ch->pc;
139 u32 val;
140 int ret;
141
142 ret = pm_runtime_get_sync(pc->dev);
143 if (ret < 0)
144 DRM_DEV_ERROR(pc->dev,
145 "failed to get runtime PM sync: %d\n", ret);
146
147 ret = clk_prepare_enable(pc->clk_apb);
148 if (ret)
149 DRM_DEV_ERROR(pc->dev, "%s: failed to enable apb clock: %d\n",
150 __func__, ret);
151
152 /* HSYNC to pixel link is active low. */
153 imx8qxp_pc_write_clr(pc, PC_CTRL_REG,
154 PC_DISP_HSYNC_POLARITY(ch->stream_id));
155
156 /* VSYNC to pixel link is active low. */
157 imx8qxp_pc_write_clr(pc, PC_CTRL_REG,
158 PC_DISP_VSYNC_POLARITY(ch->stream_id));
159
160 /* Data enable to pixel link is active high. */
161 imx8qxp_pc_write_set(pc, PC_CTRL_REG,
162 PC_DISP_DVALID_POLARITY(ch->stream_id));
163
164 /* Mask the first frame output which may be incomplete. */
165 imx8qxp_pc_write_set(pc, PC_CTRL_REG, PC_VSYNC_MASK_ENABLE);
166
167 /* Only support RGB currently. */
168 val = imx8qxp_pc_read(pc, PC_CTRL_REG);
169 if (ch->stream_id == 0) {
170 val &= ~PC_DISP0_PIX_DATA_FORMAT_MASK;
171 val |= PC_DISP0_PIX_DATA_FORMAT(RGB);
172 } else {
173 val &= ~PC_DISP1_PIX_DATA_FORMAT_MASK;
174 val |= PC_DISP1_PIX_DATA_FORMAT(RGB);
175 }
176 imx8qxp_pc_write(pc, PC_CTRL_REG, val);
177
178 /* Only support bypass mode currently. */
179 imx8qxp_pc_write_set(pc, PC_CTRL_REG, PC_DISP_BYPASS(ch->stream_id));
180
181 clk_disable_unprepare(pc->clk_apb);
182 }
183
184 static void
imx8qxp_pc_bridge_atomic_disable(struct drm_bridge * bridge,struct drm_bridge_state * old_bridge_state)185 imx8qxp_pc_bridge_atomic_disable(struct drm_bridge *bridge,
186 struct drm_bridge_state *old_bridge_state)
187 {
188 struct imx8qxp_pc_channel *ch = bridge->driver_private;
189 struct imx8qxp_pc *pc = ch->pc;
190 int ret;
191
192 ret = pm_runtime_put(pc->dev);
193 if (ret < 0)
194 DRM_DEV_ERROR(pc->dev, "failed to put runtime PM: %d\n", ret);
195 }
196
197 static const u32 imx8qxp_pc_bus_output_fmts[] = {
198 MEDIA_BUS_FMT_RGB888_1X36_CPADLO,
199 MEDIA_BUS_FMT_RGB666_1X36_CPADLO,
200 };
201
imx8qxp_pc_bus_output_fmt_supported(u32 fmt)202 static bool imx8qxp_pc_bus_output_fmt_supported(u32 fmt)
203 {
204 int i;
205
206 for (i = 0; i < ARRAY_SIZE(imx8qxp_pc_bus_output_fmts); i++) {
207 if (imx8qxp_pc_bus_output_fmts[i] == fmt)
208 return true;
209 }
210
211 return false;
212 }
213
214 static u32 *
imx8qxp_pc_bridge_atomic_get_input_bus_fmts(struct drm_bridge * bridge,struct drm_bridge_state * bridge_state,struct drm_crtc_state * crtc_state,struct drm_connector_state * conn_state,u32 output_fmt,unsigned int * num_input_fmts)215 imx8qxp_pc_bridge_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
216 struct drm_bridge_state *bridge_state,
217 struct drm_crtc_state *crtc_state,
218 struct drm_connector_state *conn_state,
219 u32 output_fmt,
220 unsigned int *num_input_fmts)
221 {
222 u32 *input_fmts;
223
224 if (!imx8qxp_pc_bus_output_fmt_supported(output_fmt))
225 return NULL;
226
227 *num_input_fmts = 1;
228
229 input_fmts = kmalloc(sizeof(*input_fmts), GFP_KERNEL);
230 if (!input_fmts)
231 return NULL;
232
233 switch (output_fmt) {
234 case MEDIA_BUS_FMT_RGB888_1X36_CPADLO:
235 input_fmts[0] = MEDIA_BUS_FMT_RGB888_1X30_CPADLO;
236 break;
237 case MEDIA_BUS_FMT_RGB666_1X36_CPADLO:
238 input_fmts[0] = MEDIA_BUS_FMT_RGB666_1X30_CPADLO;
239 break;
240 default:
241 kfree(input_fmts);
242 input_fmts = NULL;
243 break;
244 }
245
246 return input_fmts;
247 }
248
249 static u32 *
imx8qxp_pc_bridge_atomic_get_output_bus_fmts(struct drm_bridge * bridge,struct drm_bridge_state * bridge_state,struct drm_crtc_state * crtc_state,struct drm_connector_state * conn_state,unsigned int * num_output_fmts)250 imx8qxp_pc_bridge_atomic_get_output_bus_fmts(struct drm_bridge *bridge,
251 struct drm_bridge_state *bridge_state,
252 struct drm_crtc_state *crtc_state,
253 struct drm_connector_state *conn_state,
254 unsigned int *num_output_fmts)
255 {
256 *num_output_fmts = ARRAY_SIZE(imx8qxp_pc_bus_output_fmts);
257 return kmemdup(imx8qxp_pc_bus_output_fmts,
258 sizeof(imx8qxp_pc_bus_output_fmts), GFP_KERNEL);
259 }
260
261 static const struct drm_bridge_funcs imx8qxp_pc_bridge_funcs = {
262 .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
263 .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
264 .atomic_reset = drm_atomic_helper_bridge_reset,
265 .mode_valid = imx8qxp_pc_bridge_mode_valid,
266 .attach = imx8qxp_pc_bridge_attach,
267 .mode_set = imx8qxp_pc_bridge_mode_set,
268 .atomic_disable = imx8qxp_pc_bridge_atomic_disable,
269 .atomic_get_input_bus_fmts =
270 imx8qxp_pc_bridge_atomic_get_input_bus_fmts,
271 .atomic_get_output_bus_fmts =
272 imx8qxp_pc_bridge_atomic_get_output_bus_fmts,
273 };
274
imx8qxp_pc_bridge_probe(struct platform_device * pdev)275 static int imx8qxp_pc_bridge_probe(struct platform_device *pdev)
276 {
277 struct imx8qxp_pc *pc;
278 struct imx8qxp_pc_channel *ch;
279 struct device *dev = &pdev->dev;
280 struct device_node *np = dev->of_node;
281 struct device_node *child, *remote;
282 u32 i;
283 int ret;
284
285 pc = devm_kzalloc(dev, sizeof(*pc), GFP_KERNEL);
286 if (!pc)
287 return -ENOMEM;
288
289 pc->base = devm_platform_ioremap_resource(pdev, 0);
290 if (IS_ERR(pc->base))
291 return PTR_ERR(pc->base);
292
293 pc->dev = dev;
294
295 pc->clk_apb = devm_clk_get(dev, "apb");
296 if (IS_ERR(pc->clk_apb)) {
297 ret = PTR_ERR(pc->clk_apb);
298 if (ret != -EPROBE_DEFER)
299 DRM_DEV_ERROR(dev, "failed to get apb clock: %d\n", ret);
300 return ret;
301 }
302
303 platform_set_drvdata(pdev, pc);
304 pm_runtime_enable(dev);
305
306 for_each_available_child_of_node(np, child) {
307 ret = of_property_read_u32(child, "reg", &i);
308 if (ret || i > 1) {
309 ret = -EINVAL;
310 DRM_DEV_ERROR(dev,
311 "invalid channel(%u) node address\n", i);
312 goto free_child;
313 }
314
315 ch = &pc->ch[i];
316 ch->pc = pc;
317 ch->stream_id = i;
318
319 remote = of_graph_get_remote_node(child, 1, 0);
320 if (!remote) {
321 ret = -ENODEV;
322 DRM_DEV_ERROR(dev,
323 "channel%u failed to get port1's remote node: %d\n",
324 i, ret);
325 goto free_child;
326 }
327
328 ch->next_bridge = of_drm_find_bridge(remote);
329 if (!ch->next_bridge) {
330 of_node_put(remote);
331 ret = -EPROBE_DEFER;
332 DRM_DEV_DEBUG_DRIVER(dev,
333 "channel%u failed to find next bridge: %d\n",
334 i, ret);
335 goto free_child;
336 }
337
338 of_node_put(remote);
339
340 ch->bridge.driver_private = ch;
341 ch->bridge.funcs = &imx8qxp_pc_bridge_funcs;
342 ch->bridge.of_node = child;
343 ch->is_available = true;
344
345 drm_bridge_add(&ch->bridge);
346 }
347
348 return 0;
349
350 free_child:
351 of_node_put(child);
352
353 if (i == 1 && pc->ch[0].next_bridge)
354 drm_bridge_remove(&pc->ch[0].bridge);
355
356 pm_runtime_disable(dev);
357 return ret;
358 }
359
imx8qxp_pc_bridge_remove(struct platform_device * pdev)360 static int imx8qxp_pc_bridge_remove(struct platform_device *pdev)
361 {
362 struct imx8qxp_pc *pc = platform_get_drvdata(pdev);
363 struct imx8qxp_pc_channel *ch;
364 int i;
365
366 for (i = 0; i < 2; i++) {
367 ch = &pc->ch[i];
368
369 if (!ch->is_available)
370 continue;
371
372 drm_bridge_remove(&ch->bridge);
373 ch->is_available = false;
374 }
375
376 pm_runtime_disable(&pdev->dev);
377
378 return 0;
379 }
380
imx8qxp_pc_runtime_suspend(struct device * dev)381 static int __maybe_unused imx8qxp_pc_runtime_suspend(struct device *dev)
382 {
383 struct platform_device *pdev = to_platform_device(dev);
384 struct imx8qxp_pc *pc = platform_get_drvdata(pdev);
385 int ret;
386
387 ret = clk_prepare_enable(pc->clk_apb);
388 if (ret)
389 DRM_DEV_ERROR(pc->dev, "%s: failed to enable apb clock: %d\n",
390 __func__, ret);
391
392 /* Disable pixel combiner by full reset. */
393 imx8qxp_pc_write_clr(pc, PC_SW_RESET_REG, PC_FULL_RESET_N);
394
395 clk_disable_unprepare(pc->clk_apb);
396
397 /* Ensure the reset takes effect. */
398 usleep_range(10, 20);
399
400 return ret;
401 }
402
imx8qxp_pc_runtime_resume(struct device * dev)403 static int __maybe_unused imx8qxp_pc_runtime_resume(struct device *dev)
404 {
405 struct platform_device *pdev = to_platform_device(dev);
406 struct imx8qxp_pc *pc = platform_get_drvdata(pdev);
407 int ret;
408
409 ret = clk_prepare_enable(pc->clk_apb);
410 if (ret) {
411 DRM_DEV_ERROR(pc->dev, "%s: failed to enable apb clock: %d\n",
412 __func__, ret);
413 return ret;
414 }
415
416 /* out of reset */
417 imx8qxp_pc_write_set(pc, PC_SW_RESET_REG, PC_FULL_RESET_N);
418
419 clk_disable_unprepare(pc->clk_apb);
420
421 return ret;
422 }
423
424 static const struct dev_pm_ops imx8qxp_pc_pm_ops = {
425 SET_RUNTIME_PM_OPS(imx8qxp_pc_runtime_suspend,
426 imx8qxp_pc_runtime_resume, NULL)
427 };
428
429 static const struct of_device_id imx8qxp_pc_dt_ids[] = {
430 { .compatible = "fsl,imx8qm-pixel-combiner", },
431 { .compatible = "fsl,imx8qxp-pixel-combiner", },
432 { /* sentinel */ }
433 };
434 MODULE_DEVICE_TABLE(of, imx8qxp_pc_dt_ids);
435
436 static struct platform_driver imx8qxp_pc_bridge_driver = {
437 .probe = imx8qxp_pc_bridge_probe,
438 .remove = imx8qxp_pc_bridge_remove,
439 .driver = {
440 .pm = &imx8qxp_pc_pm_ops,
441 .name = DRIVER_NAME,
442 .of_match_table = imx8qxp_pc_dt_ids,
443 },
444 };
445 module_platform_driver(imx8qxp_pc_bridge_driver);
446
447 MODULE_DESCRIPTION("i.MX8QM/QXP pixel combiner bridge driver");
448 MODULE_AUTHOR("Liu Ying <victor.liu@nxp.com>");
449 MODULE_LICENSE("GPL v2");
450 MODULE_ALIAS("platform:" DRIVER_NAME);
451